Trace gas movement in the soil profile at the Kellogg Biological Station, Hickory Corners, MI (2010 to 2012)|Dataset Abstract The distribution of trace gasses in the soil profile was investigated using tracer and monitoring techniques. This data is part of Iurii Shcherbak thesis work. original data source http://lter.kbs.msu.edu/datasets/128|LTER,KBS,Kellogg Biological Station,Hickory Corners,Michigan,Great Lakes
Meta-analysis of N2O emissions at the Kellogg Biological Station, Hickory Corners, MI|Dataset Abstract A meta analysis of reported N2O emissions as they relate to fertilizer input. original data source http://lter.kbs.msu.edu/datasets/129|LTER,KBS,Kellogg Biological Station,Hickory Corners,Michigan,Great Lakes
History of research sites including earlier vegetation types at the Kellogg Biological Station, Hickory Corners, MI|Dataset Abstract Information about earlier vegetation, farming, etc. original data source http://lter.kbs.msu.edu/datasets/141|LTER,KBS,Kellogg Biological Station,Hickory Corners,Michigan,Great Lakes,cover type vegetation presettlement history
APT02 Monthly temperature and precipitation records from Manhattan, KS|Data set contains the monthly values of maximum, minimum and average temperatures and monthly total precipitation for Manhattan, KS since 1891. Data are in three separate files, one for each measurement. Data comes from the Weather Data Library in the computer system office of the Cooperative Extension Service of Kansas State University, Manhattan Kansas. (211 Umberger Hall, 785-532-6270)|LTER,KNZ,Konza Prairie Biological Station,Kansas,Temperature,Precipitation
Michigan GLBRC Extensive Sites at the Kellogg Biological Station, Hickory Corners, MI (2008 to 2011)|Dataset Abstract The Great Lakes Bioenergy Research Center’s (GLBRC) Extensive Sites are farm-scale fields located on working farms. Fields of corn, switchgrass, and restored prairie are represented at each of 10 locations in 13 counties in Michigan. original data source http://lter.kbs.msu.edu/datasets/106|LTER,KBS,Kellogg Biological Station,Hickory Corners,Michigan,Great Lakes,anpp,plant biomass,species,biodiversity,plant density,corn,biomass,GPS,coordinates,gps,soil,chemistry,Populations,Disturbance,Primary Production,Inorganic Nutrients
Soil Microbial Gene Sequences at the Kellogg Biological Station, Hickory Corners, MI (2004 to 2010)|Dataset Abstract Gene sequences extracted from soils. original data source http://lter.kbs.msu.edu/datasets/108|LTER,KBS,Kellogg Biological Station,Hickory Corners,Michigan,Great Lakes,gene,sequence,nitrite reductase,nirK,gene sequence,Populations,Disturbance
Plant biomass collection on the Biodiversity Experiment at the Kellogg Biological Station, Hickory Corners, MI (2001 to 2011)|Dataset Abstract The biodiversity gradient experiment is an additional long-term study located within the LTER Main Site complex, in which a series of 21 different experimental treatments vary in plant species diversity. Treatments range from bare soil to single-crop rotations to multiple-crop rotations to annually fallowed fields with early successional plant communities. Plant species richness thus varies from 0 to >15 in any given 3-year rotation cycle. Treatment plots are 9.1×27.4 meters (30×90 feet) replicated in each of 4 randomized blocks. The study site was established in 2000. original data source http://lter.kbs.msu.edu/datasets/112|LTER,KBS,Kellogg Biological Station,Hickory Corners,Michigan,Great Lakes,competition,Primary Production,Populations,Disturbance,biomass,species,diversity
Poplar Biomass by Allometric Equations at the Kellogg Biological Station, Hickory Corners, MI (1989 to 2012)|Dataset Abstract Poplars are grown as cellulose crop at the Main Cropping System Experiment. The first rotation was planted at a stocking density of 1 tree per 2 square meter. After the first harvest the trees were allowed to coppice. After the second harvest the trees were replanted. The third rotation was planted at 1 tree per 3.6 square meter. For the first two rotations the species planted was Populus nigra x P. deltoids hybrid for the third rotation it is Populus nigra x P. maximowiczii. original data source http://lter.kbs.msu.edu/datasets/120|LTER,KBS,Kellogg Biological Station,Hickory Corners,Michigan,Great Lakes,forest,biomass,poplar,coppice,branches,Primary Production,Disturbance,Populations
Nucletide Sequences from the Kellogg Biological Station at the Kellogg Biological Station, Hickory Corners, MI|Dataset Abstract Microbial nucleotide sequences isolated from soils collected from the LTER main cropping system experiment. original data source http://lter.kbs.msu.edu/datasets/121|LTER,KBS,Kellogg Biological Station,Hickory Corners,Michigan,Great Lakes
Lake Levels and Ice cover on local lakes at the Kellogg Biological Station, Hickory Corners, MI (1923 to 2015)|Dataset Abstract Lake levels and ice cover have been measured on local lakes with the help cf citizen volunteers. original data source http://lter.kbs.msu.edu/datasets/122|LTER,KBS,Kellogg Biological Station,Hickory Corners,Michigan,Great Lakes,ice cover lake
Farmer surveys at the Kellogg Biological Station, Hickory Corners, MI (2011 to 2011)|Dataset Abstract Farmers are surveyed to understand their perception of and response to climate change. This data forms part of the basis for Stuart, D., R. L. Schewe, and M. McDermott. 2012. Responding to climate change: barriers to reflexive modernization in US agriculture. Organization & Environment 25:308-327 original data source http://lter.kbs.msu.edu/datasets/123|LTER,KBS,Kellogg Biological Station,Hickory Corners,Michigan,Great Lakes,Populations
Bioenergy and Land Use Survey at the Kellogg Biological Station, Hickory Corners, MI (2012 to 2012)|Dataset Abstract The goal of this mail survey was to explore landowners’ attitudes, perceptions, and willingness to grow energy crops on marginal land in the southern half of the Lower Peninsula of Michigan. A major objective was to predict the potential supply of four potential bioenergy crops on three land types (cropland, hay & pasture land, farmable non-crop land), with special focus on the latter two categories of “marginal” land. The contingent valuation completely randomized experimental design covers four energy crops (corn, switchgrass, hybrid poplar, trees, mixed prairie) with four pre-defined rental rate offers ($50, $100, $200, $300 per acre) at one of two rental contract durations (5 or 10 years) for a total of 32 versions of the questionnaire. The area frame sample targeted owners of plots of 10 acres (4 hectares) or more of “marginal” land, using the USDA Cropland Data Layer 2010 where “marginal land” was defined as fallow cropland, shrubland, grassland, and hay or pasture. The two-stage clustered random sampling design began with random selection of 12 selected non-metropolitan counties in southern Michigan (the clusters) and within each one random selection of 100 owners of land parcels of at least 10 acres (4 ha.), where possible. The 4-wave direct mail survey asked landowners about their land uses, attitudes about their land, awareness of bioenergy crops, opinions about bioenergy and environment, concerns about land rental, and demographic background. The contingent valuation section asked for respondent willingness to rent each of the three land types for each of the four bioenergy crops at a specified rental rate for a specified contract period. The survey began in March 2012 and was completed in August 2012 original data source http://lter.kbs.msu.edu/datasets/124|LTER,KBS,Kellogg Biological Station,Hickory Corners,Michigan,Great Lakes,Populations
Jornada Grasshopper Data|This is grasshopper data sampled from 9 plots on the east bajada of the Dona Ana Mts. Three plots were situated on the bajada parallel to and 200 m south of the LTER transect. Two additional sets of three plots were located 5 km and 10 km south of the LTER transect. Each plot is composed of two 50 m belt transects, each divided into ten 5 m2 quadrats. Grasshoppers were visually sampled in each quadrat/plot, once in May, July and September, in 1983, 1984 and 1985. Each individual grasshopper, its age, sex and substrate it was observed on, are recorded.|Populations,Animal,annual patterns,assembly structure,grasshoppers,habitat,population dynamics,seasonal patterns,spatial patterns,substrates,completed
Jornada Grasshopper Plot Herbaceous Vegetation Data|This is data on annual herbaceous plants measured on Jornada grasshopper plots on the east bajada of the Dona Ana Mts. Three plots were situated on the bajada parallel to and 200m south of the LTER transect. Two additional sets of three plots were located 5km and 10km south of the LTER transect. Each plot was composed of two 50m belt transects, each divided into ten 5m2 quadrats. Annual plants were measured in the NE 1m2 of each quadrat, once in May, July and September in 1983, 1984 and 1985. All individuals of each species were counted and measured. A mean diameter, height, and the total number of individuals/1m2/quadrat were recorded.|Populations,Animal,annual patterns,annual plants,forbs,herbs,seasonal patterns,spatial patterns,grasses,completed
Fluff grass plant total nitrogen|Dry weight biomass and total nitrogen were determined for flowers, green leaves and yellow and grey leaves of fluffgrass plants collected from plots. Twenty 6 x 6 m plots were established with a 3 m buffer between plots. Five plots were randomly assigned to one of four treatments: (1) chlordane amendment 100ml AI (active ingredients) per 10,000 ml) to exclude microarthropods, (2) sprinkler irrigation (6 mm per week), (3) sprinkler irrigation (6 mm/week) plus chlordate amendment (as above), (4) control (no treatment).|inorganic nutrients,plant,chlordane,dry weights,fluffgrass,irrigation,total nitrogen,completed
Fluff grass plant growth|This data set consists of periodic size measurements of permanently marked individual fluff grass plants. Measurements were taken in March, July, and September 1986. Twenty 6 x 6 m plots were established with a 3 m buffer between plots. Five plots were randomly assigned to one of four treatments: (1) chlordane amendment 100ml AI (active ingredients) per 10,000 ml) to exclude microarthropods, (2) sprinkler irrigation (6 mm per week), (3) sprinkler irrigation (6 mm/week) plus chlordate amendment (as above), (4) control (no treatment). Three randomly located subsamples were taken from each plot.|populations,plant,chlordane,fluffgrass,irrigation,plant growth,completed
Fluff grass soil total nitrogen|Twenty 6 x 6 m plots were established with a 3 m buffer between plots. Five plots were randomly assigned to one of four treatments: (1) chlordane amendment 100ml AI (active ingredients) per 10,000 ml) to exclude microarthropods, (2) sprinkler irrigation (6 mm per week), (3) sprinkler irrigation (6 mm/week) plus chlordate amendment (as above), (4) control (no treatment). Soil total Nitrogen was determined in the rhizosphere of fluffgrass.|Inorganic Nutrients,Plant,chlordane,fluffgrass,irrigation,nitrogen,completed
Poplar response to Fertilization at the Kellogg Biological Station, Hickory Corners, MI (2012 to 2012)|Dataset Abstract The response of poplars to repeated N fertilization at different levels. original data source http://lter.kbs.msu.edu/datasets/126|LTER,KBS,Kellogg Biological Station,Hickory Corners,Michigan,Great Lakes,Inorganic Nutrients
Plant Nutrient Analysis - 1988 and 1989|Soil samples were collected from mesquite dune site, and analyzed for nutrient content in the plant.|Inorganic Nutrients,Plant,irrigation,plant nutrients,snakeweed,mesquite,completed
Mesquite Nodulating Rhizobia - 1988 and 1989|Soil samples were collected from mesquite dune site, and analyzed for the number of rhizobia nodules.|Populations,Plant,irrigation,nodules,rhizobia,mesquite,completed
Deep Core Soil Saturation Extracts|*We have hypothesized that large rhizobial population densities can occur at considerable depths in woody legume systems where deep moisture also occurs. However, associated with deep soil environments are low concentrations of soil nutrients that might affect nodulation and also limit survival of free-living rhizobia. The objectives of this study were to (1) determine if results from a previous study of a mesquite woodland utilizing groundwater in the Californian Sonoran desert were generizable to mesquite systems in other deserts where root depth varied with ecosystem type and (2) examine possible relationships of soil properties and host-plant phenology to rhizobial concentrations. Data set contains analyses for SO4, sodium, calcium, manganese, sodium-absorption-ration, total cations, electrical conductivity, pH, saturation percentage, total carbon, inorganic carbon, organic carbon, and gravimetric soil moisture.|Inorganic Nutrients,Soil,carbon analysis,deep cores,soil cores,soil saturation extract,mesquite,completed
Fern leaf nutrients observation at the Luquillo Experimental Forest (LEF)|Ferns are a common element of the understory of forests yet little is known about the dynamics of leaf production.  The long-term role of an individual fern in the ecosystem understory is a function of the number and size of leaves produced over time and the quality of those leaves.  Selected functional plant traits (see also LUQ186 -Fern nutrients) were measured in order to supplement non-destructive measurements and detect patterns of primary productivity of ferns in the long-term studies at the Luquillo forest where ferns have been included (eg. Fern growth and demography (LUQ75) Canopy Trimming Experiment (LUQ143 and LUQ146) and the Luquillo Forest Dynamics Plot). Among the important characteristics of fern leaves in the forest understory are the area and biomass of leaves needed to calculate specific leaf area (SLA) leaf dry-matter content (LDMC) and leaf shrinkage.  Therefore a large sample of whole leaves and leaf material from several species in the Luquillo Experimental Forest understory was collected weighed and leaf area measured.  The means and regression relationships among these functional traits for species leaf type and leaf size can then be used to estimate leaf production and turnover rates in temporal studies of fern growth.|populations,primary production,phosphorus,oxygen,nitrogen,elements and compounds,substances,plant growth,growth,physiological processes,processes,ferns,plants,organisms,specific leaf area,plant properties,measurements,forests,forest ecosystems,terrestrial ecosystems,ecosystems,plant ecology,ecology,biogeochemistry,disciplines
Biodiversity and metacommunity structure of rocky intertidal invertebrates in some coastal ecosystems in Puerto Rico|The goals of this study were to determine the relative importance of environmental (wave power density, wave height) and habitat (e.g., algal cover, slope, complexity of rock surfaces) factors associated with the structure of local assemblages at multiple shore heights and the regional metacommunity of mobile invertebrates on oceanic rocky intertidal habitats. These characteristics and abundances of 41 species of invertebrate were estimated at 10 plots at each of three tidal heights at each of ten sites on the shoreline of Puerto Rico.|populations,biodiversity,intertidal,biodiversity,community structure
Wood to Soil 0-10 cm data and Wood to Soil 10-20 cm data to detect the imprint of decaying logs (30-80 cm diameter) from two hurricane cohorts (Hugo, 1989, and Georges, 1998)|Many trees fell during Hurricanes Hugo (1989) and Georges (1998) in Puerto Rico. A debris removal experiment suggested that coarse woody hurricane debris slowed canopy recovery by fueling microbial nitrogen immobilization. We analyzed C, N, microbial biomass C and root length in paired soil samples taken under versus 20-50 cm away from large trunks of two species felled by Hugo and Georges three times during wet and dry seasons during the two years after Georges. Data on soil P and other nutrients have not yet been analyzed. Soil microbial biomass, C and N were higher under than near logs of both age cohorts. Frass from wood boring beetles may induce the early effects. Root length was greater under logs at 0-10 cm depth during the dry season, and away from logs in the wet season, but varied independently of microbial biomass. Thus decaying wood can provide resources exploited by tree roots. Percent soil C and N were significantly higher under than near logs in both the 0-10 and 10-20 cm samples. Microbial biomass C varied significantly among seasons at 0-10 cm depth but differences between positions (under vs away) were only suggestive. Surface soil on the upslope side of the logs had significantly more N and microbial biomass, likely from accumulation of leaf litter above the logs on steep slopes. This study shows that C and N accumulate significantly more in soil under than near decaying logs, even in logs that had only decayed for 7 months, and thus contributes to soil heterogeneity. Tree roots track and exploit resource and nutrient hotspots as they change locations between seasons, so the soil heterogeneity in soil fertility is important for forest productivity.|inorganic nutrients,organic matter,biogeochemistry,decomposition,nutrient cycling,recovery,soil carbon,soil organic matter
El Yunque Chronosequence Tree Census data|The El Yunque Chronosequence plots consist of four sites, El Verde 1 (EV1), Sabana 1 (SB1), Sabana 2 (SB2), and Sabana 3 (SB3), which are located at the edges of El Yunque National Forest at sites to the south of El Verde and Sabana Field Stations.  The plots represent a range of successional stages representing areas in agriculture or recently abandoned in 1936 but reforested after 1950, and areas in agriculture or recently abandoned in 1977 and reforested since that time.  They range in size from ~0.5 to 1 ha, vary in elevation from ~150m to 550m a.s.l. and span a wide range of ages and land use histories (Table 1). Plot Name Size Age Elevation EV1 10,000 m2 (1 ha) >62 yrs but < 76 yrs ~ 550m SB1 4,625 m2 (~0.5 ha) >62 yrs but not primary forest ~100-150m SB2 6,400 m2 (~0.6 ha) >35 yrs but < 62 yrs ~100-150m SB3 4,800 m2 (~0.5 ha) Primary forest ~100-150m One of these plots (EV1) is south of El Verde Field Station, on Forest Service land just over the property boundary.  This area was in agriculture in 1936 but appeared forested in a 1950 aerial photograph, and there are differences in forest structure and species composition consistent with the known differences in land use history.  The other three Chronosequence sites are just south of the Sabana Field Station on Forest Service Land on the opposite side of the forest from El Verde.  One plot (SB2) is located in young secondary forest in an area immediately adjacent to an old teak plantation forest.  Another plot (SB1) is located in an area that was sparsely forested in 1936 and which appeared reforested in 1950.  The third plot in Sabana (SB3) is located in a patch of primary “tabonuco†(named for the abundance of this tree species) forest on a steep slope on the west side of the Sabana River.|disturbance,primary production,forests,community composition,chronosequences,trees,plant growth,primary production,succession,disturbance,tree growth
Luquillo Understory invertebrates Sticky Trap Samples|Sticky traps, designed to resemble resin globules that eventually could become amber, were coated with adhesive and placed on lower tree boles or on logs at one non-gap site at the LEF for 5 days during June 2004, January and July 2005, July 2006 and July 2007 (total 35 samples).  Samples were dominated by Diptera (89% of specimens), with phorids representing 60%, mycetophilids 16%, dolichopodids 4%, sarcophagids 2%, cecidomyiids and chironomids 1% each, and other Diptera 5%.  Other collected taxa included Hymenoptera (6% of specimens), with chalcidoid wasps 4%, little fire ant (Wasmania auropunctata) 1% and other Hymenoptera 1%; Coleoptera (2% of specimens), with curculionids 1% and other Coleoptera 1%; and a variety of other insects, spiders and mites representing 3%.  Two small Anolis lizards and a small Eleutherodactylus frog also were captured.  Arthropod composition in sticky traps from the LEF and in Dominican amber were similar.|disturbance,populations,primary production,arthropods
Luquillo Forest Dynamics Plot (LFDP) Liana Data|Liana demographic data from the 16-Ha Big Grid (LFDP) over time: These data contain liana and tree data for two demographic censuses (summer 2001 and summer 2015) from 20 randomly selected quadrats within the LFDP (10 in the northern LFDP -cover classes 1-3 sensu Thompson et al. 2002) and 10 in the southern LFDP (cover class 4 sensu Thompson et al. 2002).|disturbance,populations,ecosystem ecology,land use history,measurements,canopy cover,plant cover,plant species composition,plants,canopy gaps,populations
Canopy Trimming Experiment (CTE) Walking Stick Data|The objective of these data is to determine how green litter deposition and canopy opening associated with a hurricane independently and jointly affect population dynamics of walking sticks (Lamponius portoricensis).|disturbance,populations,ecosystems,terrestrial ecosystems,forest ecosystems,forests,land use,methods,field methods,permanent plots,organisms,animals,invertebrates,arthropods,processes,disturbance
Elevational gradients of walking stick (Lamponius portoricensis) abundance|Abundance data were collected for Lamponius portoricensis from a mixed forest transect and from a palm dominated transect set along an elevational gradient in the Sonadora watershed. Each transect ranged from 300 m to 1000 m in elevation, with elevational strata located at 50 m intervals and 10 plots per stratum. No palm dominated forest could be located at 700 m in the watershed, resulting in 15 strata (150 plots) along the mixed forest transect and 14 strata (140 plots) along the palm forest transect. The data set includes 3 files that contain abundance data for walking sticks (Lamponius portoricensis) along an elevational gradient within the Sonadora River watershed. Two files (1 and 2) contain data from the mixed forest transect but differ in the year during which they were collected (2007 and 2008). The third file (3) contains data from a palm forest elevational transect from 2008, for which all sites were located in palm dominated forest in the same watershed. Note: Plots at 250 m of elevation were only sampled during 2007, no palm dominated forest could be located at 750 m of elevation; that elevation is omitted from the palm transect.|populations,ecosystems,terrestrial ecosystems,forest ecosystems,forests,field methods,permanent plots,organisms,animals,invertebrates,arthropods,processes,disturbance
McMurdo Dry Valleys Stream Descriptions|As part of the Long Term Ecological Research (LTER) project in the McMurdo Dry Valleys of Antarctica, a systematic sampling program has been undertaken to monitor the the glacial meltwater streams in the region. Measurements are regularly made to examine water= quality and quantity, as well as chemical and biological properties. The stream descriptions table serves as an index of the streams that have been studied. It documents the streams' basins and lengths, and provides a brief desciption of the landscape in which the streams are found.|hydrology,streams,basin,hydrology,length,stream
McMurdo Dry Valleys Stream Gage and Outlet Locations|As part of the Long Term Ecological Research (LTER) project in the McMurdo Dry Valleys of Antarctica, a systematic sampling program has been undertaken to monitor the glacial meltwater streams in the region. Measurements are regularly made to examine water quality, quantity, and chemical properties. The stream gauge and outlet locations table serves as an index of the sampling points used to collect hydrological and stream chemistry data in the McMurdo Dry Valley network of streams. It documents the latitude, longitude and elevation of all the stream sample points used for hydrological and/or chemical analysis.|hydrology,streams,chemistry,gage box,hydrology,latitude,longitude,stream,streamflow
Stream Feature Coordinates|As part of the Long Term Ecological Research (LTER) project in the McMurdo Dry Valleys of Antarctica, a systematic sampling program has been undertaken to monitor glacial meltwater stream attributes of the region. Optical topographic surveys were performed to produce a layout of the area studied. This file provides the northing, easting, and orthogonal height information for the gage boxes, flumes and rebars set up for Andersen, House, Canada, Delta and Green Creek. NOTE: These points were omitted from the plot files for the individual sites ( found in the Stream Transect Coordinate List file), since in most cases they fall outside the map area.|stream,transect,gage box,gage flume,gage rebar,northing,easting,McMurdo Dry Valleys,MCM
Canopy Trimming Experiment (CTE) plants greater than 1 centimeter diameter at breast height (DBH)|Plant diameters and growth measurements were taken both before and after treatments to determine how alterations in canopy openness and detritus affect measures of growth, mortality, and production. Both types of trimmed plots are predicted to have relatively quick evidence of re-sprouting (1-3 months; based on Hurricane Hugo studies), especially palms. Because essentially complete defoliation to the canopy took place in the trim plots, the large stems that were trimmed should experience delayed growth and higher mortality than those in non-trimmed plots. The understory vegetation, or otherwise those that were not trimmed (i.e., stems <10cm at dbh) should experience increased growth in both trim plots as a result of increased light. Some nutrient immobilization may occur in the detritus addition plots, but this is predicted to affect belowground processes most. Little influence on aboveground processes from detritus addition might occur and cause some stunted growth rates of stems.|disturbance,populations,primary production,disciplines,ecology,plant ecology,vegetation dynamics,ecosystems,terrestrial ecosystems,forest ecosystems,forests,events,disturbances,hurricanes,processes,biological processes,life history,growth,plant growth,tree growth,production,plant growth,disturbance,scientific activities,modeling,simulation,substances,biological substances,detritus
Canopy Trimming Experiment (CTE) Litter decomposition and Connectivity basket data|This experiment was designed to decouple the effects of canopy opening from those of increased detrital inputs on rates of detrital processing and resultant community and ecosystem processes. In a study initiated after massive inputs of organic matter from Hurricane Georges in 1998, the forest floor returned to prehurricane values very quickly, within 2-10 months (Ostertag et al. 2003). However, it was unclear to what extent this homeostasis was caused by increased rates of decomposition. Furthermore, if accelerated decomposition was implicated in rapid recovery, the relative contributions of environmental and resource changes wrought by canopy opening versus green leaf deposition on the forest floor were unclear because these factors are confounded in hurricane damage. A full factorial design was therefore used to tease apart the separate and combined effects of simulated storm damage on rates of mass loss in pre-weighed senesced and green litter cohorts inserted into litter decomposition baskets following application of canopy trimming and debris deposition treatments. Natural litter cohorts (i.e., organic forest floor material and subsequent natural litterfall separated into 3-month cohorts) were also weighed when replicate baskets were harvested at approximately 3-month intervals. In addition to obtaining mass and percent moisture of litter cohorts, the extent of fungal connections between litter cohorts was quantified. Fungal connections between partly decomposed and fresh leaf litter have been shown to be important in importation of phosphorus (the most limiting major nutrient in decomposition of tabonuco forest litter) into the freshly fallen leaves in order to rapidly build fungal biomass and associated acceleration of decomposition (Lodge 1993, 1996). The thickest of these fungal colonization and translocation organs (rhizomorphs, cords and hyphal strands) are primarily basidiomycete fungi, which have an almost unique capacity to cause white-rot by breaking down lignin in low-quality litter. A few white-rot basidiomycetes produce finer connections comprised of diffuse wefts of hyphae (e.g., Marasmius leoninus and related species), but the majority may represent ascomycetes and water molds that lack enzyme systems for breaking down lignin. White-rot basidiomycetes were shown in separate experiments to accelerate rates of decomposition of tabonuco leaves (Dacryodes excelsa) by 15% to 20% (Santana et al. 2005; Lodge et al. 2008), so any changes in fungal connectivity by basidiomycete fungi in response to the treatments should be related to nutrient exchanges between litter cohorts and changes in rates of mass loss.Litterbaskets are used to study decomposition and nutrient cycling questions, and are often a better for understanding interactions between different litter cohorts than are leaf decomposition bags. We know from previous work here and elsewhere that: 1) basidiomycete fungi rapidly colonize freshly fallen litter (within the first 3 weeks of litterfall) from partly decomposed litter on the forest floor using rhizomorphs and cords (Lodge and Asbury 1988); 2) these fungal root-like structures transport nutrients from the old food base in order to build their biomass in the freshly fallen leaves, and are capable of tripling the phosphorus content in a senesced tabonuco leaf as indicated using radioactive phosphorus tracer in microcosm experiments (Lodge 1993; 1996); and 3) basidiomycete colonization accelerates leaf decomposition in the LEF (Lodge et al. 2008). Fungal translocation of nutrients is probably responsible for the increase in total CONTENT of N and P in leaf litter above 100% in El Verde (as in Zou et al.) and elsewhere in the tropics within 3-6 weeks of leaf fall (see Lodge 1993). In contrast, temperate forest floor litter is not usually colonized by basidiomycete fungi from the forest floor until 9-15 months after litterfall. Translocation of phosphorus into tropical litter with low phosphorus concentrations likely contributes to accelerated rates of leaf decomposition associated with basidiomycete colonization in tabonuco forest (Lodge et al. 2008), but the enzymatic capacity of basidiomycete to degrade lignin is a contributing factor (Santana et al. 2005). Previous research in temperate forests shows a positive effect of increased litter depth on colonization by basidiomycete fungi. Unpublished data of Lodge and Asbury showed that drying of the litter layer reduced or eliminated basdiomycete colonization, while Lodge and Cantrell (1995) showed disappearance of some basidiomycete colonies in canopy gaps on ridges at El Verde after hurricane Hugo, or replacement of drought-sensitive strong nutrient translocators (i.e., Collybia johnstonii) with more drought tolerant species that translocated less P32. There were no previous data on effects of litter depth on basidiomycete fungi from tropical forests. We knew from studies after Hurricane Georges that 1. forest floor mass in secondary forest returned to pre-hurricane levels in about a year (Ostertag, Silver and Scatena?), but we did not know whether this was due to accelerated decomposition or reduced litter inputs after the storm. Thus, it was not really clear what mechanisms were involved in control of forest floor decomposition following hurricane disturbance. This litterbasket decomposition experiment was designed to mimic as closely as possible post-hurricane conditions in order to follow mass loss and nutrient content of specific litter cohorts. To this end, a layer of SURFACE AIR-DRIED tabonuco leaves was placed between two screens on top of the existing forest floor layer in the litterbaskets (on the ground). In debris-addition plots, green leaves of Dacryodes, Manilkara and Sloanea IN HURRICANE AMOUNTS (as determined in Lodge et al. 1991) were added on top of the senesced litter layer screen after the canopy manipulations were completed in the CTE plots. Additional cohorts of litterfall were demarcated using screens added to remaining baskets when these were harvested ca. quarterly. So far, we know that 1) canopy opening inhibited fungal connectivity between litter cohorts (mostly basidiomycete fungi, but the highest counts may be from diffuse hyphal connections by ascomycetes and water molds); 2) addition of green litter buffered the layers below from drying, mostly compensating for the effects of canopy opening; 3) fungal connectivity to the weighed layer of senesced tabonuco leaves was positively and significantly correlated with rates of leaf decomposition; 4) litter decomposition rates were higher than in dried leaf litter in a litterbag experiment in the CTE (González et al, unpublished), as in previous unpublished comparisons of dried versus undried litter; 5) but despite this, forest floor mass had not returned to pre-hurricane levels 1.5 years after CTE initiation. The data of Cantrell and Ortíz (lterdb165) on microbial composition in the litter cohorts from these baskets used methods that cannot distinguish basidiomycetes from other fungi. The results, however, suggest that colonization by basidiomycetes colonize accelerates the rate of early leaf decomposition and changes the trajectory of community succession. Nutrient analyses to determine if increases followed by decreases in inorganic nutrient pools, especially phosphorus, are associated with changes in patterns of fungal connectivity between the litter cohorts, and whether cohorts with low connectivity at the beginning have net losses rather than net gains in N and P stores.|canopy trimming experiment (CTE),Luquillo Experimental Forest (LEF),Luquillo,Puerto Rico,Greater Antilles,Caribbean,Sites,Sites Projects Programs,Basidiomycetes,Fungi,Fungi algae lichens slime-molds bacteria,white-rot,nutrient translocation,Community dynamics,Ecological phenomena processes,hurricane disturbance,natural disturbance,Disturbance and Land Use,litterfall cohorts,Natural or anthropogenic materials,litter decomposition,Interactions of element cycles,phosphorus,nitrogen,carbon,Individual elements,mass loss,Biotic Controls,Biogeochemistry Controls,Biogeochemistry,phosphorus,nitrogen,carbon,elements and compounds,nutrients,biological substances,substances,translocation,litterfall,biological processes,litter decomposition,decomposition,biogeochemical processes,processes,fungi,organisms,hurricanes,disturbances,events,inorganic nutrients,organic matter,populations,Litterfall and coarse woody debris decompostion,plants,litter decomposition
Ferns surveys of individuals of terrestrial ferns in Canopy Trimming Experiment (CTE) plots document changes in species richness and abundance over time in response to canopy opening and/or debris deposition|Whole plot surveys of Canopy Triming Experiment (CTE) plots were done to detect changes in the number of terrestrial fern species and individuals in response to canopy opening and debris deposition.  Surveys were conducted annually prior to and after treatments.  A count of all terrestrial ferns, identified to species on the CTE plots was recorded for each subplot in January during CTE1 (2002-2010) and in the fall during CTE2 (2014-present).  The surveys document losses of individuals of shade tolerant fern species and the appearance of open canopy ferns such as the tree fern Cyathea arborea.|disturbance,populations,ecosystems,terrestrial ecosystems,forest ecosystems,forests,disturbances,hurricanes,population and community properties,abundance,diversity,species diversity,species richness,organisms,plants,ferns,organizational units,communities,plant communities,processes,biological processes,life history,growth,plant growth,production,plant growth,disturbance
Effects of a tropical stream poisoning: do they reflect effects of small-scale experiments?|Small-scale experiments in tropical streams have suggested that freshwater shrimps play a critical role in determining the quality and quantity of benthic organic matter and overall nutrient dynamics. We quantified the effects of a whole-reach shrimp poisoning event in the Sonadora, a second-order stream draining the Luquillo Experimental Forest in northeastern Puerto Rico. The illegal poisoning (for shrimp harvest) caused massive mortality of shrimps and aquatic insects. Atyid and xiphocaridid shrimp abundances in pools of the poisoned reach were reduced by ~95%, relative to abundances in an upstream reference reach. A survey of poisoned vs. reference pools, combined with a manipulative experiment (in which atyid and xiphocaridid shrimps were added to 3 poisoned pools), showed that reduced shrimp abundances due to the poisoning had strong impacts on benthic resources. The benthos of poisoned pools, where shrimp abundances were reduced, had 4 times more chlorophyll a, 6 times more algal biovolume, 4 times more fine particulate organic matter, 14 times more fine particulate inorganic matter, 5 times more carbon, and 4 times more nitrogen than did the benthos of pools in the reference reach. These increases in benthic resources were consistent with increases in algae, organic/inorganic matter, and nutrients in previous small-scale shrimp exclusion experiments conducted in the study river and tributaries. Effects of shrimp poisoning on the benthos varied by habitat, with riffles showing fewer significant differences than did pools. Compared to reference riffles, poisoned riffles had higher standing stocks of fine particulate inorganic matter, nitrogen, and biovolume of filamentous algae, and lower epilithic C:N ratios. Overall, previous small-scale exclusion experiments were highly predictive of the direction of effects due to large-scale shrimp removal by poisoning. Our study provides a tropical data set to add to the short list of stream studies that examine the predictive power of small-scale experiments for larger scales.|disturbance,chlorine,elements and compounds,substances,crabs,crustaceans,invertebrates,animals,organisms
Pattern morphology for frogs captured at 9 locations in northeastern Puerto Rico over a 25-year period from 1978 to 2002|We recorded the pattern morph for 9,950 frogs captured at 9 locations in northeastern Puerto Rico over a 25-year period from 1978 - 2002. Data revealed 21 distinct pattern morphs including a variety of stripes, bars, and spots. Analysis of morph frequencies between plots showed significant heterogeneity, with longitudinal stripes more common in grassland and disturbed areas, and spot and bar morphs more common in forests where palm and bromeliad axils are important habitat features. Comparison of morph frequencies through time at the same sites showed temporal shifts immediately following Hurricane Hugo in 1989. We suggest that the pattern polymorphism is maintained in part by local habitat matching resulting from selection pressure from visual predators.|populations,disciplines,ecology,community dynamics,organisms,animals,vertebrates,amphibians,processes,disturbance,forest disturbance
Canopy Trimming Experiment (CTE) Snail data|The objective of these data is to determine how green litter deposition and canopy opening associated with a hurricane independently and jointly affect population dynamics and community composition of terrestrial gastropods. Because canopy openness can be expected to increase abiotic stress on gastropods, whereas litter deposition should provide increased resources and refugia, tradeoffs can be expected.|disturbance,populations,ecosystems,terrestrial ecosystems,forest ecosystems,forests,methods,field methods,permanent plots,organisms,animals,invertebrates,mollusks,gastropods,snails,processes,disturbance
Soil factors predict initial plant colonization on Puerto Rican landslides|Tropical storms are the principal cause of landslides in montane rainforests, such as the Luquillo Experimental Forest (LEF) of Puerto Rico . A storm in 2003 caused 30 new landslides in the LEF that we used to examine prior hypotheses that slope stability and organically enriched soils are prerequisites for plant colonization. We measured slope stability and litterfall in 1 m2 plots 8-13 months following landslide formation. At 13 months we also measured microtopography, soil characteristics (organic matter, particle size, total nitrogen, and water holding capacity), elevation, distance to forest edge, and canopy cover, as well as plant aboveground biomass, plant cover, and root biomass.|inorganic nutrients,organic matter,primary production,events,disturbances,measurements,ecosystem properties,canopy cover,organisms,plants,processes,biological processes,life history,colonization,litterfall,succession,disturbance,substances,sediments
Bromeliad chemistry at different elevations in the LEF|Mean concentrations of various nutrients in dried bromeliad leaf and in the coarse, medium and fine portions of debris retained by the bromeliad rosette.|inorganic nutrients,populations,measurements
Bromeliad plant collection details/data from different elevations in the LEF|Collection details of bromeliads collected for invertebrate community and diversity analysis from 4 localities in the LEF. Dates, location, plant size, amounts, pH and temp. of contained water, and weights of debris retained by the bromeliads.|inorganic nutrients,populations,measurements,organisms,plants
Species names and codes of the Luquillo Forest Dynamics Plot (LFDP), Puerto Rico|File LFDP_spp contains the current species list with family for the Luquillo Forest Dynamics plot and the codes for these species found in LFDP1 and LFDD1a As new species are encountered or renamed and species renamed then this list will be updated Species identifications are assisted by reference to Liogier (1985, 1988, 1994, 1995, 1997), Little and Wadsworth (1964) Little, et al (1974), Little and Woodbury (1976).The National Science Foundation requires that data from projects it funds are posted on the web two years after any data set has been organized and “cleaned†The data from each census of the LFDP will be updated at intervals as each survey of the LFDP shows errors in the previous data collection After posting on the web, researchers who are not part of the project are then welcome to use the data Given the enormous amount of time, effort and resources required to manage the LFDP, obtain these data, and ensure data accuracy, LFDP Principal Investigators request that researchers intending to use this data comply with the requests below Through complying with these requests we can ensure that the data are interpreted correctly, analyses are not repeated unnecessarily, beneficial collaboration between users is promoted and the Principle Investigators investment in this project is protected   Please comply with the following requests: Submit to the LFDP PIs a short (1 page) description of how you intend to use the data;Invite LFDP PIs to be co-authors on any publication that uses the data in a substantial way (some PIs may decline and other LFDP scientists may need to be included); If the LFDP PIs are not co-authors, send the PIs a draft of any paper using LFDP data, so that the PIs may comment upon it; In the methods section of any publication using LFDP data, describe that data as coming from the “Luquillo Forest Dynamics Plot, part of the Luquillo Experimental Forest Long-Term Ecological Research Programâ€; Acknowledge in any publication using LFDP data the “The Luquillo Experimental Forest Long-Term Ecological Research Program, supported by the U.S National Science Foundation, the University of Puerto Rico, and the International Institute of Tropical Forestryâ€; Supply the LFDP PIs with 10 reprints of any publication using LFDP data. Accept that the LFDP PIs can not guarantee that the LFDP data you intend to use, has not already been submitted for publication or published.|disturbance,populations,primary production
Shrimp populations variability in numbers and sizes in response to disturbance and seasons on 20 pools along the reach of Quebrada Prieta, Luquillo Experimental Forest|Shrimp populations were monitored at approximately 3 week intervals to determine the variability in numbers and sizes of each species in response to disturbance and seasons.|populations
Fern distribution in El Verde MRCE plots|A fern survey was done of the plots established by under MRCE funding to assess controls on primary productivity along an elevational gradient. The control plots (CP), fertilized plots (FP) and plots where only leaf litter (ll) was removed at El Verde were survey and all ferns present in the plots listed, mapped and measured in Fall of 1995, several years after the initial fertilization and leaf litter treatment had been applied. The objective was to determine the extent to which the fern flora had been affected by the treatments.|primary production,nutrients,biological substances,substances,plant growth,production,biological processes,processes,ferns,plants,organisms
Experimental Understory Food Web data in the El Verde area of the Luquillo Experimental Forest|These data include date, treatment, block number, number of coquies, number of anoles, number of insects collected on two sticky traps, number of insects counted on 4 Piper glabrescens and 4 Manilkara bidentata seedlings, percent herbivory on the aforementioned plants and number of spiders. All these measurements were taken within exclosures for closed controls, anole exclusions, coqui exclusions and total exclusions. Open controls were sampled from an area of similar dimension not enclosed in an exclosure.|populations,primary production,herbivory,species interactions,biological processes,processes,food webs,organizational units,lizards,reptiles,amphibians,vertebrates,insects,arthropods,invertebrates,animals,organisms
Long-Term Elevation Plots (LTEP) (Altitudinal transects vegetation data along three rivers in the Luquillo Experimental Forest)|The composition of plant communities changes with elevation in the Luquillo Experimental Forest (LEF). The goal of this project is to document the patterns of these changes, and in particular, to determine whether the distributions of individual species are independent of one another, or whether they are related, in either a congruent or a hierarchical manner. Thirty-two permanent vegetation plots, each 50m by 20m are being established in the LEF, with 5 plots along the Icacos river, 11 along the Mamayes river and 16 along the Sonadora stream. The plots were established at every 100m in elevation, starting at 200m above sea level. All woody, free-standing stems greater than 1cm dbh were marked, identified and mapped into 5x5 subquadrats. We anticipated that gradient analysis will show whether the distributions of species are coincident or independent, enabling us to evaluate whether separate, genuine plant communities exist in the LEF. Because the plots are permanent, we also expected that they allow us to better evaluate how different vegetation types, at different elevations, respond to large scale disturbances, especially hurricanes.|el verde field station (EVFS),dwarf forest,colorado forest,Luquillo Experimental Forest (LEF),Luquillo,Puerto Rico,Greater Antilles,Caribbean,Sites,Sites Projects Programs,elevational gradients,Landscapes,tabonuco forest,altitude,Forest Structure,Habitat and Forest-structure,plant diversity,plant community composition,Community dynamics,Ecological phenomena processes,community structure,communities,organizational units,plants,organisms,elevation,spatial properties,measurements,forests,forest ecosystems,terrestrial ecosystems,ecosystems,community dynamics,ecology,species diversity,biodiversity,disciplines,populations,Plant community tree regeneration plant phenology,plants,seedling dynamics
Factors influencing decomposition of leaves for five plant species at El Verde|We evaluated the influences of leaf quality, climate and microsite on the decomposition of leaves of five tropical tree species. Single-species litterbags were used to determine weight loss during the first three months of decomposition in the Luquillo Experimental Forest, Puerto Rico. Significant differences were found in decomposition rates among leaf species (Inga fagifolia < I. vera < Manilkara bidentata < C-roton poecilanthus << Sapium laurocerasus), but only S. laurocerasus differed significantly from the other species. Lignin had a suggestive negative correlation with leaf decomposition while carbon content and the lignin:N ratio were significantly correlated with mass loss. Content of N, P, Ca, and polyphenol were not significantly correlated with mass loss, but several of the litter quality variables were correlated with each other. Leaf species decomposed faster under canopies of their source trees than in a common plot where the source species were absent. Decomposition in two species in the Euphorbiaceae, S. laurocerasus and C. poecilanthus, was significantly affected by microsite. Leaching losses during the first three weeks were greater under source trees than in the common plot, and may have been associated with differences in canopy structure and throughfall. Differences in detrital communities, however, could have contributed to the differences in decomposition between microsites. Leaves of all species decomposed significantly faster in the wet than in the dry period (P = 0.001) despite little climatic variation in this subtropical wet forest type. This suggests that decomposition of tropical leaf litter might be sensitive to microclimatic changes on the forest floor resulting from either global climate change, or from natural or anthropogenic disturbances that open the canopy.|inorganic nutrients,organic matter,populations,primary production
Interactions between plants and fungi and their roles in decay rates and CO2 release in five tropical leaf species|A microcosm experiment was used to test for the effects of interactions between particular plant and fungal decomposer species on rates of leaf decomposition. Each microcosm contained one species of leaf that was sterilized with gamma irradiation and then inoculated with a single fungus. Five plant species and ten fungal species (two dominants from each of the litter types) were used in all possible combinations. Plant species were selected for pair-wise comparisons based on phylogenetic relationships and litter quality characteristics. Decomposition was measured by both mass loss and CO2 release. Differences in weight loss and CO2 evolution were highly significant for plants, fungal species, and their interactions. Mass loss was positively correlated with CO2 evolution. Contrary to our hypotheses, however, microfungal dominants did not decompose their source leaves faster than microfungal dominants from other leaf species, nor were responses to other types of specificity detected. Matching of fungi to leaf substrates by their source, by phylogenetic relationships, or by chemical, physical and structural characteristics was not associated with consistent increases in decomposition. Although previously documented differences in microfungal species composition and dominance among decomposing leaves of different trees were confirmed in this study, such differences apparently do not directly affect the rates of ecosystem processes. The presence in a few of the microcosms of a generalist basidiomycete that had ligninolytic enzymes, Melanotus eccentricus, significantly accelerated the rate of decomposition. Non-specific basidiomycetes may therefore have a stronger effect on early stages of leaf litter decomposition than host-selective microfungi.|inorganic nutrients,organic matter,populations,primary production,carbon dioxide,carbon,elements and compounds,substances,leaf decomposition,decomposition,biogeochemical processes,processes,leaf litter,vegetation,plants,basidiomycetes,fungi,organisms,forests,forest ecosystems,terrestrial ecosystems,ecosystems
Canopy Trimming Experiment (CTE) Canopy invertebrate responses to disturbance|Seven tree species were selected to represent early (Cecropia, Prestoea) and late (Dacryodes, Manilkara, Sloanea) successional, and overstory (Cecropia, Dacryodes, Manilkara, Sloanea) and understory (Prestoea, Miconia, Psychotria), species in forests at El Verde. These trees were sampled in all CTE plots.|populations,primary production,organisms,animals,invertebrates,arthropods,insects,mites,processes,disturbance
Daily streamflow (Bisley area, 5 stations: Q1, Q2, Q3, Sabana, Puente Roto)|The daily data are summarized to monthly as follows: Daily average CFS are summed for each month and multiplied by 86400 (seconds per day) to yield cubic feet per month. This value is divided by the particular watershed area and multiplied by another conversion factor to yield cm water equivalent depth discharged by each watershed per month. This allows direct hydrologic comparison of watersheds of different sizes. Time series plots illustrate the biennial periodicity of high and low discharges, and particular floods and droughts. October 1970 was the historic flood for PR, recently exceeded during the passage of Hurricane Hortense in September 1996. The historic drought occurred during 1993-1994 and is clearly visible in these records.|inorganic nutrients,primary production,monitoring,modeling,scientific activities,discharge,hydrologic processes,physical processes,processes,weather,atmospheric properties,measurements,meteorology,disciplines
Canopy Trimming Experiment (CTE) litterbag invertebrate counts and weights data|Identification, number and dry weight of invertebrates recovered from each litterbag.|disturbance,organic matter,populations,disturbance patterns,invertebrates,herbivory
Physical and chemical attributes of Quebrada Prieta, Bisley 3, Bisley 5, and Toronja related to shrimp populations measurements|<p>Physical parameters, d<span>ensities and sizes of two species of freshwater shrimps (<em>Atya lanipes</em> and <em>Xiphocaris elongata</em>) in four headwater streams (</span><span class="SpellE">Quebrada</span> <span class="SpellE">Prieta</span>, <span class="SpellE">Toronja</span>, <span class="SpellE">Bisley</span> 3 and <span class="SpellE">Bisley</span> 5) have been <span class="SpellE">censused</span> 2 times yearly since 1998 <span>to determine the effects of predatory fishes on shrimp size and spatial distributions of pools relative to locations of waterfalls. </span></p>|inorganic nutrients,populations,ecosystems,aquatic ecosystems,streams,organisms,animals,invertebrates,aquatic invertebrates
Canopy Trimming Experiment (CTE) Microbial EL-FAME Data|The canopy trimming experiment at El Verde simulates some aspects (canopy openness and biomass redistribution) of hurricane disturbances. Soil samples and leaf litter were gathered from three replicate blocks, each with four treatment plots in Tabonuco Forest at in El Verde. Treatments (canopy trimming and debris addition) were applied in a 2 x 2 factorial design. Samples were obtained both before and after the canopy were trimmed and debris was applied in the appropriate treatments. Samples were collected every four months before and after treatments were applied. Molecular approaches such as EL-FAME are useful indicators of microbial community shifts in response to environmental change. In this experiment we analyzed microbial community composition and abundance in soil and leaf litter samples as reflected by EL-FAME profiles. All soil samples were cleaned by removing rocks and roots, and leaf litter samples were ground. Fatty acid nomenclature: Fatty acids are named according to the conversion X:YωZ, where X represents the number of carbon atoms in the chain, followed by Y after the colon which represents the degree of the unsaturation. The symbol ω and Z represent the number of double bonds nearest to the carboxyl end. The prefixes a, i, cy and d refer to anteiso, iso, cyclopropyl branching and dicarboxylic fatty acid respectively; br indicates that the type of branching is unknown, while a number followed by Me indicates position of methyl group. Prefixes a and b indicate that the OH groups of an OH fatty acid are located at positions 2 and 3 respectively. Numbers preceded by w indicate the position of OH groups from the aliphatic end of the fatty acids (Kaur et al 2005). Community analysis based on fatty acids: Fatty acid biomarkers could represent a group of particular microorganisms present in soil and leaf litter. Fatty acids used in literature as biomarkers are: Branched chain fatty acids (br 17:0, br 18:0, i17:0, a17:0, i16:0, i16:1, 10Me16:0, 10Me17:0), iso and anteiso isomers of 15:0 for gram positive bacteria; Cyclopropane fatty acids (cy17:0, cy19:0, 16:1w9, 16:1w7c, 16:1w5, 18:1w7,19:1) for gram-negative bacteria; 18:2w6 for fungi; 10Me16:0, 10Me17 : 0 and 10Me18 : 0 for Actinomycetes; cy17:0 and 10Me16:0 for Sulphate reducing bacteria; 16:1w8, 18:1w8 for Methanogens (Modified from Zelles, 1999; Kaur et al 2005).|disturbance,populations,measurements,population and community properties,community composition,organisms,fungi,plants,vegetation,leaf litter,organizational units,communities,processes,biological processes,litterfall,microbial activity,disturbance,substrates,soil
Bromeliad invertebrates at different elevations in Dominica|Collection details of bromeliads collected for invertebrate community and diversity analysis from 3 localities in Dominica. Dates, location, plant size, amounts, pH and temp. of contained water, weights of debris retained by the bromeliads, and counts of organisms, identified to species or morphospecies, collected from each plant.|populations
Canopy Trimming Experiment (CTE) Litterfall|This data set shows forest litter production and its response to the canopy trimming and debris addition or removal treatments. In addition, it shows patterns of interannual variation that can be related to environmental variables. In combination with data set 111 (MRCE Litterfall data), this is the long-term monitoring of leaf litter production at El Verde Research Area.  The data reported here are for mass of litterfall pooled among collection baskets placed in the inner 20x20 m measurement plots collected at two-week intervals, beginning two years before the first treatments were applied. The litter mass data are reported for litter separated by plant parts. Litterfall contributes to mobilization of organic matter and nutrients from primary producers to soil.|organic matter,primary production,phenology,hurricanes,seasonality,litterfall,recovery
Patterns in litterfall production from 12 forested sites along an elevation gradient in Pico del Este|We measured litterfall from 12 sites along an upper elevation gradient every two weeks from 1994 to present. Samples are being used to estimate the litterfall productivity over time and space, identify the impacts of periodic events, and help us understand the drivers of ecosystem and biogeochemical processes with climate and vegetation change.|disturbance,primary production,processes,biological processes,litterfall
Canopy Trimming Experiment (CTE) trace gases|This data set provides the monthly trace effluxes measured across the soil-atmosphere interface from five soil surface chambers in all the CTE plots.|disturbance,inorganic nutrients,nitrous oxide,nitrogen compounds,nitrogen,methane,carbon dioxide,carbon,elements and compounds,substances
Canopy Trimming Experiment (CTE) Plot Treatments|This data set is updated every time a trim is performed on the plots. The last trim was in 2014. The Luquillo Experimental Forest LTER program in Puerto Rico was initially focused on the understanding of the effects that two major hurricanes, Hugo in 1989 and George in 1998, had on the structure and function of a tropical mountain forest and how the biota responded to these disturbances. This focus provided insights into the key characteristics of disturbance that alter forest function over long time scales.  After several years of research through the LEF-LTER program, it became clear that one primary effect of disturbances associated with the impact of a hurricane is to redistribute organic matter from live biomass compartments to the detrital pool.  Then a combination of biotic and abiotic processes, all modified by the disturbance, contributes to the decomposition of detritus and to the subsequent fate of associated C and nutrients. These critical regulating processes define detrital dynamics and play a central role in the recovery of forest structure and function by regulating decomposition and therefore carbon and nutrient storage and flow. Our understanding of hurricane impacts comes from measurements of the effects of naturally occurring hurricanes on tabonuco forest and comparisons with similar disturbances in other forests (Walker et al. 1991, 1996a).  Base on the evaluation of long-term measurements after the impact of hurricane Hugo and George it becomes clear that the two primary effects of hurricane disturbance are changes in microclimate and redistribution of biomass, and that the interaction of both factors propagate through the system in complex ways.  These measurements are informative but cannot tease apart the effects of various aspects of hurricane disturbance and suffer from the lack of a control or reference condition.  From this assessment the LUQ-LTER principal investigators jointly identified the need for an experimental manipulation to decouple the effect of shifts in resource availability due to redistribution of biomass and altered microclimate conditions due to canopy opening on community and ecosystem processes and forest recovery. As a long term experiment, the CTE is also designed to help evaluating predictions regarding the effects of an increased intensity and rate of hurricane disturbance on tabonuco forest (Sanford et al. 1991) as predicted by climate change models for Caribbean hurricanes (Emmanuel 1987, Goldenberg et al. 2001).  This long-term experiment will increase the frequency of simulated hurricane effects above background levels to once every six years. The experiment will determine effects of repeated disturbance of the forest canopy and increased detrital inputs to the forest floor on germination, growth, survival, nutrient cycling, soil conditions, and trophic structure.|disturbance,events,disturbances,hurricanes,methods,field methods,permanent plots,processes,disturbance
Chemistry of soil solution collected from zero tension lysimeters in the Canopy Trimming Experiment (CTE) plots|Soil solution chemistry: Soil solution was collected monthly from zero tension lysimeters installed in the CTE plots. Sampling began prior to cutting the canopy and continue to the present.|disturbance,inorganic nutrients,lysimeter,field methods,methods,soil solution chemistry,chemistry,disciplines
Urban-Rural Temperature Data-relation between land-cover and the Urban Heat Island in San Juan, Puerto Rico|Our objective in this study is to quantify the UHI created by the San Juan Metropolitan Area over space and time using temperature data collected by mobile and fixed-station measurements. We used the fixed-station measurements to examine the relation between average temperature at a given location and the density of vegetation located upwind. We then regressed temperatures against regional land-cover to predict future temperature with projected land-cover change. Our data show the existence of a nocturnal UHI, with average nighttime urban-rural temperature differences (ΔTU-R) of up to 3.02°C. Each of the stations listed in this excel file were used to calculate the urban heat island created by the San Juan Metropolitan Area.|disturbance,measurements,atmospheric properties,climate,weather,physical properties,temperature,air temperature
2004 Estuarine Fish Sampling - Managing freshwater inflow to estuaries in northeast Puerto Rico|Chapter 1 (fish community data): Historical data are often one of the only resources for documenting and assessing causes of environmental change, particularly in developing regions where funding for ecological studies is limited. In this study, previously unpublished data from a 1977 year-long study of the fish community of the Espiritu Santo estuary are presented. This dataset is among the oldest and most extensive surveys of a Caribbean island estuarine fish community. A comparison of these historical data with data collected in June and July 2004 using identical sampling methods allowed description of potential long-term changes in the fish community, identification of vulnerable species, and assessment of potential drivers of change. Results strongly suggest a decline in species richness and abundance in the Espiritu Santo estuarine fish community, with greater declines in freshwater-tolerant than marine or euryhaline species. Declines in freshwater inflow to the estuary, due to large-scale upstream water abstractions for municipal use, have increased since the initial 1977 survey. This is the first study to examine long-term change in the fish community of a tropical island estuary. Additional research and conservation efforts are needed to understand mechanisms of change and to protect Caribbean island estuarine fish communities. Chapter 2 (isotope and gut content data): The contribution of riverine-derived organisms and organic matter to four fishes along the salinity gradient in two Puerto Rican estuaries, the Espiritu Santo and Mameyes, was examined via stable isotope and gut content analyses. Stable isotope analyses indicated that riverine organic matter potentially contributed as much as 69% of the diet of one (caitipa mojarra, Diapterus rhombeus) of four fishes sampled. In contrast, riverine organic matter was of little direct importance to the three other fishes, tarpon snook (Centropomus pectinatus), ground croaker (Bairdiella ronchus), and white mullet (Mugil curema) contributing less than a third of their assimilated material even in the estuaries’ upper reaches. Gut content analysis of estuarine fishes demonstrated that several species of pelagic or omnivorous fish consume riverine-derived organisms, specifically juvenile migratory freshwater shrimps, during their residence in the estuary. Freshwater shrimps were frequently encountered (in 37 and 39% of guts examined) and composed an average of 18 and 22% of gut content material of omnivorous fishes sampled in the Espiritu Santo and Mameyes estuaries, respectively. To our knowledge, this is the first study to examine the contribution of riverine subsidies to a Caribbean island estuary. Given increasing demand for water resources on tropical islands and the importance of diadromy in these systems, there is a need for additional research on this topic to better inform water management decisions.|disturbance,populations,ecosystems,aquatic ecosystems,estuaries,organisms,animals,vertebrates,fishes,organizational units,food webs,substances,isotopes,stable isotopes,substrates,freshwater
Enclosure/exclosure experiments in a montane Puerto Rican stream examining direct and indirect effects of two dominant taxa of atyid (Atyidae) shrimp, Atya lanipes Holthius and Xiphocaris elongata Guerin-Meneville (Shrimp/ Algae/ Oecologia (1993))|Freshwater shrimp dominate the faunal biomass of many tropical headwater streams: however, their role in community organization is unclear. Enclosure/exclosure experiments in a montane Puerto Rican stream examined direct and indirect effects of two dominant taxa of atyid (Atyidae) shrimp, Atya lanipes Holthius and Xiphocaris elongata Guerin-Meneville. Both shrimp taxa caused significant reductions in sediment cover on rock substrata, reducing sedimentation and enhancing algal biovolume on clay tiles in cages. When tiles incubated in shrimp exclosures for 2 wks were placed outside of cages, atyid shrimp removed 100% of sediment cover within a 30 min. observation period. Atyid shrimp appear to play an important role in stream recovery after high discharge events in rapidly removing sediments and detritus deposited on benthic substrata in pools. We evaluated the mechanism by which A. lanipes influences algae and benthic insects by comparing patterns of algal biomass, taxonomic composition and shrimp-presence treatments both with and without manual sediment removal. The shrimp exclusion treatment without manual sediment removal had significantly lower algal biomass and greater sedimentation than all other treatments. The treatment in which shrimp were excluded but sediment was manually removed, however, accrued almost the same algal biovolume as the shrimp enclosure treatment, supporting the hypothesis that sediment removal enhances the biovolume of understory algal taxa. Algal community composition was similar between stream bottom bedrock exposed to natural densities of shrimp and all experimental treatments for both Atya and Xiphocaris: a diatom community strongly dominated (78-95%) by the adnate taxon, Achnanthes lanceolata Breb ex. Kutz. Atyid shrimp are important in determining the distribution and abundance of benthic insects through both direct and indirect effects. Sessile, retreat-building chironomid larvae (Chironomidae: Diptera) are negatively affected by both A. lanipes and X.elongata, through direct removal by foraging activities and/or indirectly through depression of sediment resources available to larvae for the construction of retreats. In contrast, the mobile grazer, Cleodes maculipes (Baetidae: Ephemeroptera) was not adversely affected and atyid shrimp have the potential to exert positive indirect effects on this taxon by facilitating its exploitation of algal resources and/or through enhancement of understory algal food resources through sediment removal.|inorganic nutrients,sedimentation,geological processes,physical processes,processes,community structure,communities,organizational units,crustaceans,invertebrates,animals,algae,organisms,community composition,population and community properties,measurements,streams,aquatic ecosystems,ecosystems
Effects of biotic (shrimp) and abiotic (discharge) factors on the depositional environment quantified in a montane stream in Puerto Rico. (Shrimp/Algae/Can J. Fish Aquat. Sci. (1994))|Effects of biotic (shrimp) and abiotic (discharge) factors on the depositional environment were quantified in a montane stream in Puerto Rico. Electricity was used experimentally to exclude large (approximately >1cm in length) biota without artificially increasing sedimentation as in cage enclosure/exclosure experiments in stream systems. Shrimp (>1cm in length) were excluded from substrata by semicircular fence hooked up to battery-powered fence chargers which emitted continuous pulses of electricity. Unelectrified control substrata had natural high densities of atyid shrimp. Significantly greater masses of total sediment, fine and large organic particles, and algal biovolume occurred in shrimp exclusion treatments relative to controls. Shrimp exclusion treatments experienced slow and steady accumulation of sediments under base flow conditions and a large stepwise increase in sediment following a storm. No measurable sediment accrued in the presence of natural densities of shrimp under base flow conditions. Shrimp rapidly removed sediments that accrued during the storm (440-620 g*m2 dry mass-1), decreasing sediment mass in control treatments to near prestorm levels (5-13 g*m2 dry mass-1) within 30 h. Atyid shrimp can significantly affect the accumulation of organic and inorganic materials on rock substrata in stream pools between high-discharge events.|disturbance,populations,sediments,particulates,substances,electric exclusion,scientific activities,processes,diatoms,algae,organisms,streams,rivers,aquatic ecosystems,ecosystems
Patterns in soil and physical properties of the Bisley Watersheds 1 and 2 (Big Dig 1988, Big Dig 1990)|(1) Exchangeable cation concentrations were measured using different soil extracting procedures (fresh soil and air-dried and ground soil) to establish a range of nutrient availability in the soil, and to determine the relationship between different, but commonly used laboratory protocols.(2) Soils extracted using fresh soils generally yielded significantly lower exchangeable Ca , Mg, and K concentrations than soils which were dried and ground prior to extraction. Soil nutrients generally decreased with depth in the soil.(3) Several soil properties varied predictably across the landscape and could be viewed in the context of a simple catena model. In the surface soils, exchangeable base cation concentrations and pH decreased along a gradient from ridge tops to riparian valleys, while soil organic matter, exchangeable Fe and acidity increased along this gradient. On the ridges, N,P, and K were positively correlated with soil organic matter; on slopes, N and P were positively correlated with organic matter, and Ca, Kg, and pH were negatively correlated with exchangeable Fe. (4) Soil nutrient availability in the upper catena appears to be primarily controlled by biotic processes, particularly the accumulation of organic matter. Periodic flooding and impeded drainage in the lower catena resulted in a more heterogeneous environment. Drying and grinding the soil prior to extraction had a greater impact on exchangeable cations from the upper catena than in the valley positions, probably due to greater soil organic matter content. See Silver, W.L., F.N. Scatena, A.H. Johnson, T.G. Siccama, and M.J. Sanchez. 1994. Nutrient availability in a montane wet tropical forest in Puerto Rico: spatial patterns and methodological considerations. Plant and Soil 164:129-145.|Luquillo,Puerto Rico,Greater Antilles,Caribbean,Sites,Sites Projects Programs,tropical forest ecology,Fields of ecology,plant/soil interactions,Community dynamics,Ecological phenomena processes,nutrient cycles,nutrient availability,Interactions of element cycles,Biogeochemistry,soil,substrates,plants,organisms,nutrient cycles,ecosystem properties,measurements,watersheds,forests,forest ecosystems,terrestrial ecosystems,rivers,aquatic ecosystems,ecosystems,ecology,biogeochemistry,disciplines,disturbance,inorganic nutrients,organic matter,Water and atmospheric chemistry soils nutrients,plants,forest structure, biomass, tree species composition
Rio Icacos hyporheic and riparian chemistry|Hydrologic and chemical characteristics were determined for both riparian and hyporheic subsurface flow along a 100-m reach of a sandy-bottom tributary of the Rio Icacos in the Luquillo Experimental Forest, Puerto Rico. Hydrologic data (vertical hydraulic gradient and hydraulic conductivity of streambed sediments) and the topographic and morphological features of the watershed indicated diffuse inputs of groundwater from the near-stream riparian zone along this site. Cumulative groundwater discharge, determined by tracer dilution techniques, was ~1.5 L/s or 10% of the total stream discharge. Spatial heterogeneity in hydrologic and chemical properties of riparian and hyporheic sediments was large. Hydraulic conductivity explained much of the variation in NH4-N and dissolved organic carbon (DOC) concentrations, with highest concentrations in sites having low conductivity. A mass-balance approach was used to examine the influence of the near-stream zone on nutrient transport and retention. Outwelling riparian groundwater had the potential to increase stream N concentrations by up to 84% and DOC concentrations by up to 38% along our 100-m reach. Because stream concentrations were constant downstream despite this input, we conclude that significant N and C retention or loss were occurring in the near-stream zone. Lotic ecosystems and their associated riparian groundwater can have a quantitatively significant impact on the nutrient budgets of tropical headwater catchments.|inorganic nutrients,hyporheic zone,substrates,nitrogen,dissolved organic carbon,carbon,elements and compounds,substances,nutrient cycling,biogeochemical processes,processes,riparian,spatial properties,hydrological properties,measurements,rivers,aquatic ecosystems,ecosystems
Spatial Variation of Soil Carbon, Nitrogen and Phosphorus in the Luquillo Experimental Forest (LEF) (LEF_SOIL_CNP)|Hongqing Wang, a Ph.D graduate student of SUNY-ESF, with the help of many others, took soil samples in 119 locations over the entire Luquillo Experimental Forest (LEF) during the summer of 1998 and 1999. Soil organic carbon, total nitrogen and acid-extractable phosphorus were measured in the laboratory of SUNY-ESF; soil moisture and bulk density were measured at the laboratory of the El Verde Station of UPR. The geodetic coordinates (Lat., Lon.) and elevation of each sampling location were determined using a Global Positioning System (GPS Pathfinder Basic Receivers, Trimble Navigation Ltd.) in the field. Meanwhile, slope angle, aspect and topographic features (Ridge, slope I (<35 deg.), slope II (>=35 deg.), valleys) were also measured and observed in the field.|inorganic nutrients,organic matter,soil,substrates,soil moisture,water,phosphorus,nitrogen,soil carbon,organic carbon,carbon,elements and compounds,substances,spatial variability,spatial properties,bulk density,physical properties,nitrogen content,chemical properties,measurements
Landslide Removal Experiment vegetation cover and pole touches|The purpose of this data set is to document recovery of vegetation in removal plots in landslides in the Luquillo Experimental Forest (LEF.)|primary production,disturbance,processes,plants,organisms,forests,forest ecosystems,terrestrial ecosystems,ecosystems
Seedling and sapling dynamics of treefall pits and undisturbed florest floor in El Verde, Puerto Rico|Seedling and sapling dynamics in a Puerto Rican rain forest were compared between forest understory and soil pits created by the uprooting of 27 trees during Hurricane Hugo. No difference in N and P levels were found in pit or forest soils under two trees with N-fixing symbionts (Inga laurina and Ormosia krugii) compared to soils under a tree species without N-fixing symbionts (Casearia arborea), but other soil variables ( Al, Fe, K) did vary by tree species.|nitrogen,elements and compounds,soil nutrients,nutrients,biological substances,substances,nitrogen fixation,nitrogen cycling,nutrient cycling,biogeochemical processes,processes,trees,plants,organisms,hurricanes,disturbances,events,forests,forest ecosystems,terrestrial ecosystems,ecosystems
Rio Mameyes diatoms in the Rio Mameyes from 1998 to 2001|Survey expeditions of the diatoms of Puerto Rico and other Caribbean islands were conducted briefly in the late 1800's and early 1900's,. However, until now no intensive study of changes in freshwater diatom community over time has been undertaken. In conjunction with other measures of quality of water in the Rio Mameyes, i.e. pH, conductivity, temperature, nutrients, periphytic diatoms have been collected monthly for two years in an effort to detect the effects of disturbances such as hurricanes and human demands on a river ecosystem.|disturbance,primary production,aquatic ecosystems,rivers,algae,diatoms,herbivores,human disturbance
Short-term disappearance of foliar litter of three tree species native to rain forest of Puerto Rico|Litter disappearance was examined before (1989) and after (1990) Hurricane Hugo in the Luquillo Experimental Forest, Puerto Rico using mesh litterbags containing abscised Cyrilla racemiflora or Dacryodes excelsa leaves or fresh Prestoea montana leaves. Biomass and nitrogen dynamics were compared among: i) species; ii) mid- and high-elevation forest types; iii) riparian and upland sites; and iv) among pre- and post-hurricane disturbed environments. Biomass disappearance was compared using multiple regression and negative exponential models in which the slopes were estimates of the decomposition rates subsequent to apparent leaching losses and the y-intercepts were indices of initial mass losses (leaching). C. racemiflora leaves with low nitrogen (0.39 %) and high lignin (22.1 %) content decayed at a low rate and immobilized available nitrogen. D. excelsa leaves had moderate nitrogen (0.67 %) and lignin (16.6 %) content, decayed at moderate rates, and maintained the initial nitrogen mass. P. montana foliage had high nitrogen (1.76 %) and moderate lignin (16.7 %) content and rapidly lost both mass and nitrogen. There were not significant differences in litter disappearance and nitrogen dynamics among forest types and slope positions. Initial mass loss of C. racemiflora leaves was lower in 1990 but the subsequent decomposition rate did not change. Initial mass losses and the overall decomposition rates were lower in 1990 than in 1989 for D. excelsa. D. excelsa and C. racemiflora litter immobilized nitrogen in 1990 but released 10-15% of their initial N in 1989, whereas P. montana released nitrogen in both years (25-40 %). Observed differences in litter disappearance rates between years may have been due to differences in the timing of precipitation. Foliar litter inputs during post-hurricane recovery of vegetation in Puerto Rico may serve to immobilize and conserve site nitrogen.|inorganic nutrients
Heliconia invertebrate counts|Identification and number of invertebrates recovered from each Heliconia inflorescence sampled.|organic matter,populations,species richness,abundance,herbs
Bromeliad invertebrate counts at different elevations in the LEF|Identification and number of invertebrates recovered from each bromeliad sampled. Collection details of bromeliads collected for invertebrate community and diversity analysis from 3 localities in the Luquillo Experimental Forest. Dates, elevations and forest types, plant size, amounts, pH and temp. of contained water, weights of debris retained by the bromeliads, and counts of organisms, identified to species or morphospecies, collected from each plant.|organic matter,populations,disciplines,biodiversity,species richness,events,biological events,flowering,measurements,population and community properties,abundance,diversity,organisms,plants
Heliconia fluid and organic matter analyses|Mineral concentrations of Heliconia bract fluid and organic matter accumulated in the bracts. Data collected during a study of the invertebrates in Heliconia bract fluid.|organic matter,populations
Heliconia collection data|Mineral concentrations of Heliconia bract fluid and organic matter accumulated in the bracts. Data collected during a study of the invertebrates in Heliconia bract fluid.|organic matter,populations
Recovery of a tropical stream after a harvest-related chlorine poisoning event|1. Harvest-related poisoning events are common in tropical streams, yet research on stream recovery has largely been limited to temperate streams and generally does not include any measures of ecosystem function, such as leaf breakdown. 2. We assessed recovery of a second-order, high-gradient stream draining the Luquillo Experimental Forest, Puerto Rico, three months after a chlorine-bleach poisoning event. The illegal poisoning of freshwater shrimps for harvest caused massive mortality of shrimps and dramatic changes in those ecosystem properties influenced by shrimps. We determined recovery potential using an established recovery index and assessed actual recovery by examining whether the poisoned reach returned to conditions resembling an undisturbed upstream reference reach.3. Recovery potential was excellent (score=729 out of a possible 729) and can be attributed to nearby sources of organisms for colonization, the mobility of dominant organisms, unimpaired habitat, rapid flushing and processing of chlorine, and location within a national forest.4. Actual recovery was substantial. Comparison of the reference reach with the formerly poisoned reach indicated: (1) complete recovery of xiphocaridid and palaemonid shrimp population abundances, shrimp size distributions, leaf breakdown rates, and abundances of oligochaetes and mayflies on leaves, and (2) only small differences in atyid shrimp abundance and community and ecosystem properties influenced by atyid shrimps (standing stocks of epilithic fine inorganic and organic matter, chlorophyll a, and abundances of chironomids and copepods on leaves). 5. There was no detectable pattern between any measured variables and distance downstream from the poisoning. However, shrimp size-distributions indicated that the observed recovery may represent a source-sink dynamic, in which the poisoned reach acts as a sink which depletes adult shrimp populations from surrounding undisturbed habitats. Thus, the rapid recovery observed in this study is consistent with results from other field studies of pulse chlorine disturbances, harvest-related fish poisonings, and recovery of freshwater biotic interactions, but it is unlikely to be sustainable if multiple poisonings deplete adult populations to the extent that juvenile recruitment does not offset adult shrimp mortality.|disturbance,ecosystems,aquatic ecosystems,streams,measurements,spatial properties,land use,organisms,animals,invertebrates,crustaceans,processes,disturbance,human disturbance,recovery
Bisley Watershed 3 and Quebrada Prieta Algae Monitoring|The LTER is conducting annual monitoring of Algae, Chlorophyll a, benthic organic matter, and benthic inorganic matter in order to document baseline stream characteristics. These data may be used to examine effects of disturbances such as hurricanes on stream ecosystems.|organic matter,primary production,ecosystems,aquatic ecosystems,streams,organisms,algae,processes,scientific activities,monitoring,substances,biological substances,chlorophyll a,inorganic matter,organic matter
Litter invertebrate communities at different elevations in the LEF|Identification and number of invertebrates recovered from each litter sample.|populations
Conservation and management of migratory fauna and dams in tropical streams of Puerto Rico|1. Compared to most other tropical regions, Puerto Rico appears to have dammed its running waters decades earlier and to a greater degree. The island has more large dams per unit area than many countries in both tropical and temperate regions (e.g., 3x that of the U.S.), and the peak rate of large dam construction occurred two and three decades prior to reported peak rates in Latin America, Asia and Africa.2. Puerto Rico is a potential window into the future of freshwater migratory fauna in tropical regions, given the island's extent and magnitude of dam development and the available scientific information on ecology and management of the island's migratory fauna.3. We review ecology, management and conservation of migratory fauna in relation to dams in Puerto Rico. Our review includes a synthesis of recent and unpublished observations on upstream effects of large dams on migratory fauna and an analysis of patterns in free crest spillway discharge across Puerto Rican reservoirs. Analyses suggest that large dams with rare spillway discharge cause near, not complete, extirpation of upstream populations of migratory fauna. They also suggest several management and conservation issues in need of further research and consideration. These include research on the costs, benefits and effectiveness of simple fish/shrimp passage designs involving simulating spillway discharge and the appropriateness of establishing predatory fishes in reservoirs of historically fishless drainages.|experimental scale,Methods,Methods and Products,tropical island streams,Landscapes,dams,Habitat and Forest-structure,freshwater shrimps,Freshwater crustaceans,Invertebrates,migratory fauna,diadromy,Aquatic animals behavior,Animals,aquatic invertebrates,invertebrates,animals,organisms,streams,aquatic ecosystems,ecosystems,disturbance,populations,Stream ecology,streamwater
Indirect upstream effects of dams: consequences of migratory consumer extirpation in Puerto Rico|<p>Large dams degrade the integrity of a wide variety of ecosystems, yet direct downstream effects of dams have received the most attention from ecosystem managers and researchers. We investigated indirect upstream effects of dams resulting from decimation of migratory freshwater shrimp and fish populations in Puerto Rico, USA, in both high- and low-gradient streams. In high-gradient streams above large dams, native shrimps and fishes were extremely rare, whereas similar sites without large dams had high abundances of native consumers. Losses of native fauna above dams dramatically altered their basal food resources and assemblages of invertebrate competitors and prey. Compared to pools in high-gradient streams with no large dams, pool epilithon above dams had 9 times more algal biomass, 20 times more fine benthic organic matter (FBOM), 65 times more fine benthic inorganic matter (FBIM), 28 times more carbon (C), 19 times more nitrogen (N), and 4 times more non-decapod invertebrate biomass. High-gradient riffles upstream from large dams had 5 times more FBIM than did undammed riffles but showed no difference in algal abundance, FBOM, or non-decapod invertebrate biomass. For epilithon of low-gradient streams, differences in basal resources between pools above large dams vs. without large dams were considerably smaller in magnitude than those observed for pools in high-gradient sites. These results match previous stream experiments in which the strength of native shrimp and fish effects increased with stream gradient. Our results demonstrate that dams can indirectly affect upstream free-flowing reaches by eliminating strong top-down effects of consumers. Migratory omnivorous shrimps and fishes occur throughout the tropics, and the consequences of their declines upstream from many tropical dams are likely to be similar to those in Puerto Rico. Thus, ecological effects of migratory fauna loss upstream from dams encompass a wider variety of species interactions and biomes than the bottom-up effects (i.e., elimination of salmonid nutrient subsidies) recognized for northern temperate systems.</p>|disturbance
Neritina snails upstream migrations at the intersection of Rio Mameyes with road PR Route 3 (bridge 1771)|This data set includes N. virginea densities and sizes from two channels in lower Rio Mameyes under PR Route 3 bridge during the upstream migration season Aug-Dec 2000. Microhabitat use (near-bed water velocities and depth) within both channels is also included. Massive migrations in long trails occurring on the sloped concrete embankment of the main channel were also documented during 99 weeks. Individual size from migratory aggregations was measured during selected dates.|disturbance,populations
Neritina snails hierarchical distribution|This data set includes N. virginea densities and sizes relative to streambed substrate type, water depth, and habitat type in a low land reach in Río Mameyes near PR Route 3 bridge, and presence and inland extent of distribution of in 32 coastal rivers around the island. Hydrologic and water chemistry variables are reported as predictors of snail distribution at regional and stream-network scales.|disturbance,populations
Does the River Continuum Concept apply on a tropical island? Longitudinal variation in a Puerto Rican stream|We examined whether a tropical stream in Puerto Rico matched predictions of the River Continuum Concept (RCC) for macroinvertebrate functional feeding groups (FFGs). Sampling sites for macroinvertebrates, basal resources, and fishes ranged from headwaters to within 2.5 km of the fourth-order estuary. In a comparison to a model temperate system where RCC predictions generally held, we used catchment area as a measure of stream size in order to examine truncated RCC predictions (i.e., cut off to correspond to the largest stream size sampled in Puerto Rico). Despite dominance of generalist freshwater shrimps, which use more than one feeding mode, RCC predictions held for scrapers, shredders, and predators. Collector-filterers showed a trend opposite that predicted by the RCC, but patterns in basal resources suggest that this is consistent with the central RCC theme: longitudinal distributions of FFGs follow longitudinal patterns in basal resources. Alternatively, the filterer pattern may be explained by fish predation affecting distributions of filter-feeding shrimp. Our results indicate that the RCC generally applies to running waters on tropical islands. However, additional theoretical and field studies across a broad array of stream types should examine whether the RCC needs to be refined to reflect the potential influence of top-down trophic controls on FFG distributions.|populations,organisms,animals,invertebrates,crustaceans,macroinvertebrates,vertebrates,fishes
Chemistry of rainfall and throughfall from El Verde and Bisley|Rain, throughfall, and stream water are collected weekly at the LEF sites listed below. These data sets begin as early as 1983; LTER sampling began in 1988. Rain and throughfall samples are the total catch for the week, and are exposed to field conditions for that time. No event sampling is conducted on a routine basis. Rain samples from WDEV are wet only from an automatically-closing collector that prevents any dry deposition (Aerochem Metrics NADP collector). RCEV and RCB are bulk or always-open collectors that receive dry deposition by sedimentation. All samples are measured for pH and conductivity, and then filtered (pre-combusted Whatman GF/F glass fiber filter) prior to further analysis. From 1983-1994 samples were cooled and returned to the San Juan chemistry laboratory for analysis. During those years, samples for NH4 and NO3 analyses were refrigerated continuously until analysis. Subsamples for NH4 analysis were also preserved with 1 molar H2SO4. From 1994 on, samples for NH4 and NO3 were frozen until analysis, were not acidified, and all analyses were conducted at the University of New Hampshire. Rain and Throughfall Sampling SitesDescriptions of LTER LUQ rain and throughfall weekly sample chemistry data from 1988 onwards. Chemical concentrations are recorded as mg/L or mg/L as appropriate. Values below detection limits are recorded as 1/2 the detection limit. Site Abbreviation Description Comments Rain collector Bisley . RCB Bulk collector.   Rain collector El Verde  RCEV  Bulk collector.   Wet/dry El Verde . WDEV. Wet only collector.   Throughfall Bisley. TFB=TCB TF bulk 10-collector composite   Bisley gap . BGAP . TF bulk 10-collector composite  |inorganic nutrients,disciplines,chemistry,water chemistry,ecosystems,terrestrial ecosystems,forest ecosystems,forests,watersheds,measurements,ecosystem properties,nutrient cycles,hydrological properties,precipitation,rain,throughfall,processes,physical processes,atmospheric processes,deposition,wet deposition,substances,biological substances,nutrients,elements and compounds,cadmium,carbon,dissolved inorganic carbon,dissolved organic carbon,chlorine,chloride,magnesium,nitrogen,nitrogen compounds,ammonium,nitrate,phosphorus,phosphate,potassium,sodium,sulfur,sulfate
Lotic Intersite Nitrogen eXperiment I (LINX1): Stream nitrogen (N) dynamics in streams on the eastern side of Puerto Rico|This study was part of the Lotic Intersite Nitrogen eXperiment (LINX); a series of identical 15NH4 tracer additions to streams throughout North America. 15NH4Cl was added at tracer levels to a Puerto Rican stream for 42 days. Samples were collected from selected food web and dissolved nitrogen compartments throughout the addition and for several weeks afterwards to determine the uptake, retention and transformation pathways of nitrogen in the stream.|inorganic nutrients,disciplines,biogeochemistry,biology,chemistry,ecology,hydrology,ecosystems,aquatic ecosystems,measurements,chemical properties,ecosystem properties,water properties,methods,field methods,organisms,algae,animals,fungi,lichens,microbes,bacteria,seston,processes,biogeochemical processes,biological processes,substances,biological substances,inorganic matter,organic matter,water,substrates,freshwater,water column
Lotic Intersite Nitrogen eXperiment II (LINX2): Stream nitrogen (N) dynamics in streams on the eastern side of Puerto Rico|Stream nitrogen (N) dynamics were studied in streams on the eastern side of Puerto Rico. Rates of nitrate uptake and denitrification were measured in nine tropical low-order streams with contrasting land use as part of the Lotic Intersite Nitrogen eXperiment II (LINX II) in Puerto Rico using short term (24-hour) additions of K15NO3 and NaBr. Background nitrate concentrations ranged from 105 to 997 µg N L-1 and stream nitrate uptake lengths were long, varying from 315 to 8480 m (median of 1200 m). Other indices of nitrate uptake (Vf,, cm s-1 and U, ï­g N m-2 s-1) were low in comparison to other regions and were related to chemical, biological, and physical parameters. Denitrification rates were highly variable (0 to 133 ï­g N m-2 min-1; median = 15), were dominated by the end product N2 (rather than N2O), and were best predicted by whole-stream respiration rates and stream NO3 concentration. Denitrification accounted for 1 to 97% of nitrate uptake with 5 of 9 streams having 35% or more of nitrate uptake via denitrification, showing that denitrification is a substantial sink for nitrate in tropical streams. Whole-stream nitrate uptake and denitrification in our study streams closely followed 1st order uptake kinetics, indicating that NO3 uptake is limited by delivery of substrate (NO3) to the organisms involved in uptake or denitrification.|inorganic nutrients,disciplines,biogeochemistry,biology,chemistry,ecology,hydrology,ecosystems,aquatic ecosystems,measurements,chemical properties,ecosystem properties,spatial properties,land use,water properties,methods,field methods,organisms,algae,fungi,humans,lichens,microbes,bacteria,seston,processes,biogeochemical processes,biological processes,disturbance,substances,biological substances,inorganic matter,isotopes,organic matter,substrates,freshwater,water column
Elevation Gradient (EG) Soil Microbial diversity FAME and TRFLP data|Soil fungal communities respond to multiple abiotic and biotic factors that change along elevation gradients. The limited information available on fungi and microbial processes along elevation gradients is primarily from temperate areas and very few from tropical regions. This study documents changes in fungal and bacterial diversity, and abundance and composition of microbial functional groups along a subtropical elevation gradient.|populations,organisms,fungi,processes,biogeochemical processes
Canopy Trimming Experiment (CTE) Microbial diversity DNA data|Hurricanes are common disturbances in the Caribbean region that affect tree distribution, species diversity and biomass in forests. Little is known of how microbial communities in soil and litter are affected by natural or anthropogenic disturbances. The objective of our study was to determine the relative abundance and diversity of microorganisms in leaf litter at different stages of decomposition, and the effect of canopy opening and debris addition or removal. Results: Leaf mass loss was slowest in the treatment with canopy trimming and debris removal. Canopy opening was associated with lower litter moisture, lower fungal connectivity between litter layers and slower mass loss after three months. Addition of green leaves increased moisture, and frequently accelerated mass loss of the senesced leaves below them at 17, 28 and 40.5, but not 53 weeks. After 28 weeks, mass loss showed a significant treatment interaction, and was concordant with fungal connectivity between litter cohorts. TRFLP profiles of the 16S rDNA digested with MnlI and fungal ITS digested with HaeIII shows that the microbial communities at 17, 28 and 53 weeks were highly divergent among treatments (Sorensen index of similarity). In comparisons of green versus senesced leaves within treatments, bacterial communities’ differed somewhat, fungal communities differed strongly, but mass loss did not differ. Conclusions: Microbial community changes through time can be related to microclimate and the availability of labile compounds. Fungi appeared to control the succession of microorganisms in decomposing leaves.|disturbance,populations
Maximum temperature at El Verde Field Station, Rio Grande, Puerto Rico from January 1975 to August 1992|Daily emperature has been measured at the El Verde Field Station since 1975 (see methods). Average record show that maximum values for maximum temperature recorded from May to October with a range from 29 to 30 and peaks of 29.7 Centigrade in October. The months of October through December show the most dramatic increase, specially December. Highest average maximum temperatures during these years were recorded in 1998 and 1999.|el verde field station (EVFS),Luquillo Experimental Forest (LEF),Luquillo,Puerto Rico,Greater Antilles,Caribbean,Sites,Sites Projects Programs,maximum temperature,Fields of ecology,Ecological phenomena processes,maximum temperature,temperature,physical properties,measurements,primary production,Climate and stream flow,meteorology,air temperature
Sonadora elevational plots: long-term monitoring of air temperature|This is a long-term monitoring of air temperature at each elevation plot along the Sonadora gradient. At each plot a HOBO sensor is located close to the middle of the plot: at 1m above ground: and placed inside a radiation shield (a plastic cup). Sensors are programmed to sample and store air temperature every hour. A daily average is computed from hourly readings. Sensors are downloaded twice a year: thus blanks represent sensor malfunction: loss of battery: or memory full. Initial blanks were due to lack of enough sensors to cover the gradient|disturbance,events,disturbances,measurements,physical properties,temperature,air temperature,methods,field methods,surface elevation table
El Verde Field Station Air temperature from automatic sensor|This is a long-term monitoring of air temperature in the same box where we measure manual min-max temperature at El Verde Field Station. The data set is meant as a back up to the long-term manual data set. Data is measured hourly using a HOBO Pendant data logger placed inside a wooden box: under the shade of trees. The min-max thermometer that is measured manually during work days is located next to the HOBO in the same box.|disturbance,disciplines,meteorology,ecosystems,aquatic ecosystems,streams,events,disturbances,measurements,physical properties,temperature,air temperature,methods,field methods,dataloggers,processes,disturbance,forest disturbance,substrates,air
Leaf litter collected using baskets over the middle of the channel in Prieta arm B and Gatos|This is a long-term monitoring of leaf litter inputs into Prieta Stream, arm B, and into the Gatos stream. The monitoring is conducted using litter traps similar tho those used in other LTER project. Baskets are suspended over the channel and are emptied every other week. All material is dried and identified.|primary production,disciplines,ecology,stream ecology,ecosystems,aquatic ecosystems,streams,organisms,plants,flowers,seeds,vegetation,leaf litter,substances,biological substances,litter,woody debris,substrates,freshwater
Fern leaf traits observation at the Luquillo Experimental Forest (LEF)|Ferns are a common element of the understory of forests, yet little is known about the dynamics of leaf production. The long-term role of an individual fern in the ecosystem understory is a function of the number and size of leaves produced over time and the quality of those leaves. Selected functional plant traits (see also LUQ186 -Fern nutrients) were measured in order to supplement non-destructive measurements and detect patterns of primary productivity of ferns in the long-term studies at the Luquillo forest where ferns have been included (eg. Fern growth and demography (LUQ75), Canopy Trimming Experiment (LUQ143 and LUQ146) and the Luquillo Forest Dynamics Plot). Among the important characteristics of fern leaves in the forest understory are the area and biomass of leaves needed to calculate specific leaf area (SLA), leaf dry-matter content (LDMC) and leaf shrinkage. Therefore a large sample of whole leaves and leaf material from several species in the Luquillo Experimental Forest understory was collected, weighed and leaf area measured. The means and regression relationships among these functional traits for species, leaf type and leaf size can then be used to estimate leaf production and turnover rates in temporal studies of fern growth.|populations,primary production,plant growth,production,biological processes,processes,understory vegetation,vegetation,ferns,plants,organisms,specific leaf area,plant properties,measurements
Phrynus habitat selection|This data set comprises a single data file, which contains data on the abundance and distribution of the whipspider Phrynus longipes on the Luquillo Forest Dynamics Plot in July 2001.|populations,organisms,animals,invertebrates,organizational units,habitats,processes,biological processes,evolution,adaptation,life history,habitat selection,substrates
Coarse Woody Debris in Bisley Experimental Forest and the Rio Icacos Basin|Organic matter pools appear to differ in composition between Bisley and Icacos. On average (n=30), 79% of Bisley organic matter was composed of coarse woody debris. Of the remaining 21% organic matter pool, approximately 2% was from leaves, 9% was from fruit, 9% was from miscellaneous matter, and 1% was from wood matter with diameters < 2.5 cm. In comparison, 57% (n=30) of Icacos organic matter was composed of coarse woody debris. Of the remaining 43% organic matter pool, approximately 0% was from fruit, 16% was from leaves, 10% was from miscellaneous matter, and 18% was from wood matter with diameters < 2.5 cm. The data suggest a less recalcitrant organic matter pool in the Icacos environment and higher rates of turnover than in the Bisley environment. It was also apparent that woody matter (< 2.5 cm diameter) deposition was a significant source of OM inputs in the Icacos plots.|organic matter
McMurdo Dry Valleys Pulse-Press Project (P3), since 2011|Climate warming in polar regions is associated with thawing of permafrost, resulting in significant changes in soil hydrology, biogeochemical cycling, and in the activity and composition of soil communities. While ongoing, directional climate warming can elicit such responses over decadal time scales, their manifestation typically occurs as discrete thawing pulses. Indeed, in the McMurdo Dry Valleys of Antarctica abrupt changes in community structure and biogeochemical cycling in terrestrial and aquatic ecosystems following a summer warming event (Jan. 2002) exceeded the influences of a decadal cooling trend in both magnitude and rate of response. Thus, we anticipate that climate-mediated permafrost changes and their associated impacts on soil communities and biogeochemical cycles may occur over seasonal time scales. Our objective is to simulate different frequencies of permafrost thawing events in Antarctic permafrost soils. Since the top horizons of most Antarctic soils are dry permafrost (i.e., there is insufficient water content to generate ice-cement), with ice-cement or massive ice typically below 30 cm, permafrost thawing events are likely to result in subsurface movements of water that may manifest as groundwater seeps down gradient.|nematodes,rotifers,soil moisture,soil water content,Antarctica,Eudorylaimus,invertebrate,LTER,nematodes,Plectus,Pulse-Press,rotifers,Scottnema,soil,soil moisture,soil temperature,tardigrade,disturbance
McMurdo Dry Valleys Halogen chemistry and isotopic composition in McMurdo lake waters and pore fluids|As part of a collaborative investigation between researchers at Rice University, Arkansas State University, University of Rochester, and Ohio State University, lakes of the McMurdo Dry Valleys were sampled at discreet depth intervals during the 2005-2006 field season.  Sample splits were subsequently analyzed for chemical and isotopic composition of both gases and dissolved  ions, as well as dissolved organic carbon. In addition, cryogenic salts were sampled in the surrounding lake shores in order to determine the salt sources. Gravity cores were also obtained and the pore waters were collected by centrifuging the wet sediment.   Presented  in this file are the dissolved halogens :chloride, bromide, and total iodine in lake waters and pore waters. The isotopic composition of I-129 and Cl-36 are also presented for these same samples, as are the molar ratios of I-129/I-127, and Cl-36/Cl-37.   Alkalinity was also determined in order to subsequently investigate the relationship between the oxidation of organic matter and the release of iodine into the lake waters.|isotopes,lakes,limnology,alkalinity,chemistry,Cl-36,halogen,I-129,lake,limnology,inorganic nutrients
McMurdo Dry Valleys Iodine content and I-129 isotopic composition in McMurdo lake-bottom sediments|As part of a collaborative investigation between researchers at Rice University, Arkansas State University, University of Rochester, and Ohio State University, lakes of the McMurdo Dry Valleys were sampled at discreet depth intervals during the 2005-2006 field season.  Sample splits were subsequently analyzed for chemical and isotopic composition of both gases and dissolved  ions, as well as dissolved organic carbon. In addition, cryogenic salts were sampled in the surrounding lake shores in order to determine the salt sources. Gravity cores were also obtained and the pore waters were collected by centrifuging the wet sediment.    Presented  in this file is the total iodine content and I-129 isotopic composition of lake-bottom sediments from Lakes Joyce and Fryxell. An attempt was made to determine the  iodine and chlorine isotopic content  of gypsum cored from the bottom of Lake Vanda, but the total iodine content was below detection.             |chemical properties,chemistry,lakes,limnology,sedimentation,sediments,chemistry,Cl-36,I-129,lake,limnology,sediment,inorganic nutrients
McMurdo Dry Valleys Mineralogic composition of cryogenic evaporites determined by low-temperature X-ray diffactometry|As part of a collaborative investigation between researchers at Rice University, Arkansas State University, University of Rochester, and Ohio State University, lakes of the McMurdo Dry Valleys were sampled at discreet depth intervals during the 2005-2006 field season.  Sample splits were subsequently analyzed for chemical and isotopic composition of both gases and dissolved  ions, as well as dissolved organic carbon. In addition, cryogenic salts were sampled in the surrounding lake shores in order to determine the salt sources. Gravity cores were also obtained and in the case of Lake Vanda, a white precipitate was recovered from the lake bottom.              Presented  in this file is the mineralogic composition of salt crusts that were collected on the surface of sediment and rocks surrounding the lakes, as well as the lake-bottom precipitate from Lake Vanda.  The results are based on low-temperature XRD determinations, and Rietveld refinement of whole peaks.             |chemical properties,chemistry,lakes,limnology,chemistry,Cl-36,evaporite,halogen,I-129,lake,limnology,sediment,inorganic nutrients
McMurdo Dry Valleys Gas, Tritium, Stable Isotope, and Major Ion data for lake waters: 2005-2006 Antarctic Season|Data of dissolved gas, tritium, stable isotopes, and major ion for Lake Vanda (Wright Valley), Lake Fryxell (Taylor Valley), Lake Hoare (Taylor Valley), and Lake Joyce (Pearce Valley): 2005-2006 Antarctic Season|anions,cations,deuterium,lakes,limnology,anions,cations,deuterium,lake,limnology,tritium
McMurdo Dry Valleys Basic GIS Map Layers - up to 2007|Basic Layers from the MCM-LTER spatial data holdings have been exported and symbolized, and they are available for download here. Most of these layers date from Oct-2007 or earlier, please see the Polar GeoSpatial Center for more updated base and specialized layers. The spatial GIS layers contained in this ZIP file were exported from the 2006 MCM-LTER Spatial Database (now deprecated) in the ESRI Shape File format. For your convenience, Layer Files (.lyr),  which are already symbolized, are also included. The spatial layers contained in the MCM-LTER Spatial Database are accurate (depending on the date the shapefiles in this ZIP file were last exported, they may be out of date).  List of layers:   Camp locations.lyr glacier stake locations.lyr glaciers.lyr lakes and ponds.lyr maximum extent.lyr met station locations.lyr ocean.lyr stream gauge locations.lyr streams - monitored.lyr streams - not monitored.lyr topo 50m.lyr  |geographic information systems,glacier,lake,latitude,length,location,longitude,stream