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openCC0Nov 2024View details →

Point-count bird censusing: long-term monitoring of bird abundance and diversity in central Arizona-Phoenix, ongoing since 2000

### project overview Over the past half-century, the greater Phoenix metropolitan area (GPMA) has been one of the fastest growing regions in the US, experiencing rapid urban expansion in addition to urban intensification. This backdrop provides an ideal setting to monitor biodiversity changes in response to urbanization, and the CAP LTER has been using a standardized point-count protocol to monitor the bird community in the GPMA and surrounding Sonoran desert region since 2000. The bird survey locations in this CAP LTER core monitoring program include six general site groupings: 1. ESCA. Forty bird survey locations were selected from a subset of the CAP LTER's Ecological Survey of Central Arizona (ESCA; formerly named Survey200) long-term monitoring sites. ESCA sites were located using a tessellation-stratified dual-density sampling design, and, as such, span a diversity of habitats including urban, suburban, rural, commercial areas, parks, agricultural fields, and native Sonoran desert. Earlier versions of this data package included data from the ESCA project that was intended to complement the bird data. However, while positioned in close proximity, the bird survey locations do not necessarily overlap with the 30m x 30m plot that constitutes an ESCA sampling location, and leveraging data from these two monitoring programs should be addressed carefully. ESCA data have corresponding survey location names, and those data are available through the CAP LTER and LTER network data portals. At the conclusion of the 2016 spring survey, fifteen of the ESCA-correlated sites were discontinued as the core monitoring program refocused its efforts on desert parks and PASS neighborhoods. Among the deleted locations were all agricultural and commercial sites, as well as sites where access had become restrictive. 2. North Desert Village (NDV). Additional bird survey locations were positioned in treatment areas of the North Desert Village (NDV). This was a site of intense study on t

openCC0Feb 2025View details →

Long-term seasonally and annually aggregated climatic variables for the greater Phoenix, Arizona, USA, metropolitan area and the surrounding Sonoran desert, derived from single-day NASA Daymet images, 2000 to 2022

This data package consists of multiple decades of bioclimatic raster data across the Central Arizona-Phoenix Long-Term Ecological Research (CAP LTER) study area within metropolitan Phoenix, Arizona, USA, temporally aggregated by year and by four meteorological seasons (winter, spring, summer, fall). We sourced each bioclimatic variable from 1-km resolution gridded estimates of daily climatic data from NASA Daymet V4, including daily mean (ppt) and total precipitation (ppt_sum), daily maximum air temperature (temp_max), daily minimum air temperature (temp_min), incident shortwave radiation flux density (srad), and daily average partial pressure of water vapor (vp). For each of these six variables, we created temporally aggregated raster images by calculating mean pixel-values of each for each season and year, as well as producing a seventh variable of seasonally and annually summed precipitation (ppt_sum). Finally, we exported images as individual GeoTIFF raster files, each with five bands corresponding values summarized annually (band 1) and seasonally (bands 2-5). All imagery retrieval and data processing were completed with Google Earth Engine (Gorelick et al. 2017) and program R. A complete description of data processing methods, including the aggregation of imagery by year and season, can be found in the data package metadata (see 'Methods and Protocols') and accompanying Javascript code. ### citations - Gorelick N, Hancher M, Dixon M, et al. (2017) Google Earth Engine: Planetary-scale geospatial analysis for everyone. Remote Sensing of Environment 202:18–27. https://doi.org/10.1016/j.rse.2017.06.031

openCC (other)Dec 2025View details →

Soil Physical Data from the Shark River Slough, Everglades National Park (FCE), from November 2000 to January 2007

Soil pH, Eh and temperature readings are taken at SRS1b, SRS1c, SRS1d, SRS2 and SRS3. These measurements are taken only when the marsh is wet. Measurements are taken using an Orion model 250A meter, and the probes attached to the meter are the Orion Thermo pH probe and the Orion Eh probe. All readings are recorded in field notebooks, and then transferred into Microsoft Excel. The Eh reading is taken when the Eh probe is attached to the meter and the word "Ready" appears on the meter screen. The pH and temperature reading are taken when the pH probe is attached to the meter and the word "Ready" appears on the meter screen.

Net Carbon Exchange of an Old-Growth Hemlock Forest at Harvard Forest HEM Tower since 2000

This project estimates carbon exchange rates of multiple forest types at Harvard Forest (see HF072) and compares them to long-term ongoing carbon exchange measurements at the EMS, which is located in a mesic, 60-90 year old red oak and red maple dominated forest on abandoned farmland (HF004). Measurements in each forest type are used to investigate climatic influences on carbon exchange. This mesic hemlock-dominated forest with most trees 100-200 years old on undisturbed soils stored only about 3 Mg/ha of carbon in 2001, compared to over 4 Mg/ha in the 60-90 year old oak/maple stand. However, both sites stored more carbon in 2001 than was measured in the oak/maple stand in any previous year since 1991 (see HF004). The hemlock forest behaved very differently from the oak-maple stand in that the highest rates of carbon storage occurred in spring, while there was very little carbon storage in mid to late summer. Statistical models of carbon exchange in the hemlock forest showed that carbon storage was positively related to daily minimum air temperature in spring, but negatively correlated with soil temperature in the summer. The first effect was attributable to a positive influence of above-freezing minimum temperatures on photosynthesis by hemlock foliage. The negative relationship of soil temperature to carbon storage by hemlock forest in summer was due to exponentially increasing soil and ecosystem respiration, accompanied by a neutral or negative effect of high air temperature on photosynthesis by hemlock trees (see HF063). These effects indicate that carbon storage in the hemlock forest could be strongly affected by climate warming, but the effects will probably be in opposite directions in spring and summer.

Tree Growth in Hemlock and Deciduous Forests at Harvard Forest HEM and LPH Towers 2000-2005

Tree growth was measured to determine tree ages and growth rates and to quantify carbon storage in these forests, and to detect changes in growth and carbon storage that could be associated with climate changes or historic disturbances.

Influence of Little Ice Age on New England Vegetation from 2000 BP to Present

This multi-proxy study uses paleoecological, paleolimnological, and historical approaches to reconstruct climate, vegetation, and cultural dynamics over the past 1500 years at sites arrayed across the climatic and forest gradients of New England and to place these results in a regional framework through analysis of pollen records from the North American Pollen Database. High resolution records were obtained using pollen to interpret vegetation history; chironomids, stable isotopes, geochemistry, and diatoms, supplemented by historical reconstructions, to interpret climate history; charcoal and land-use data to document the human impacts; and Pb-210 and C-14 for chronological control. Results will provide: (1) an objective characterization of the Little Ice Age and climate history in New England, (2) comparison of pre- and post-European forest dynamics in relationship to independent environmental and land-use histories, (3) a reexamination of historical vegetation dynamics in light of prior climate an vegetation change, and (4) widespread availability of data and results through publications, symposium presentation, and the Harvard Forest Archives and web pages.

Avian Response to Hemlock Woolly Adelgid in Southern New England 2000-2001

This study examines changes in avian community composition associated with the decline and loss of eastern hemlock (Tsuga canadensis (L.) Carr.) resulting from chronic hemlock woolly adelgid (Adelges tsugae Annand; HWA) infestations. Overstory hemlock mortality was highly correlated with avian community composition. Abundance of eastern wood-pewee (Contopus virens), brown-headed cowbird (Molothrus ater), tufted titmouse (Baeolophus bicolor), white-breasted nuthatch (Sitta carolinensis), red-eyed vireo (Vireo olivaceus),hooded warbler (Wilsonia citrina), and several woodpecker species was highest at points with greater than 60% mortality. Black-throated green warbler (Dendroica virens), Acadian flycatcher (Empidonax virescens), blackburnian warbler (Dendroica fusca), and hermit thrush (Catharus guttatus) were strongly associated with intact hemlock stands that exhibit little or no mortality from HWA. Eastern hemlock has unique structural characteristics that provide important habitat for numerous bird species in the northeastern U.S. As a result, removal of hemlock by HWA has profound effects on avian communities. Black-throated green warbler, blackburnian warbler, and Acadian flycatcher are very strongly associated with hemlock forests in southern New England and appear to be the species that are particularly sensitive to hemlock removal. The hooded warbler, a species whose status is of regional concern, may actually benefit from the development of a dense seedling layer associated with high hemlock mortality.

openCC (other)Jan 2026View details →

Water quality data for Green Lakes Valley, 2000 - ongoing.

This dataset contains water quality measurements made on Green Lakes 1, 2, 3, 4, 5, and Lake Albion. Green Lake 4 was initially sampled in 2000 and is ongoing. Ongoing sampling of Green Lakes 1 was started in 2014 and ongoing sampling of Lake Albion was started in 2016. Water samples were collected for analysis of chlorophyll a and nutrient analysis (which is available in glvwatsolu.dm.data) and field measurements for pH, temperature, specific conductivity, dissolved oxygen (DO), % saturation, secchi depth, PAR. Secchi depth is recorded at the 0m row however it is a measurement of depth and so the units are meters. Most samples were collected between 0800 and 1200 MST. The first sampling date each summer occurs shortly after the ice had melted. Data are collected from an inflatable raft at the point of deepest depth or from the lake inlet and outlet when surface flow is present. The majority of chlorophyll-a the measurements were taken at the surface (0m), the metalimnion (3m), and the hypolimnion nine (usually 8-11m). However, additional measurements were taken for side projects of the long-term dataset during several of the years and are included in this dataset. Water samples from the metalimnion or hypolimnion were collected using a Van Dorne sampler, and surface samples were collected as grab samples from the water column surface, the inlet and outlet. Field measurements were conducted using a YSI either DO or multiple probe meter (2014-2017, YSI MPS 556)(2018-ongoing, YSI ProPlus) and a Li-Cor meter with a quantum sensor. Chlorophyll-a was extracted from filtered samples and absorbance was measured before and after acidification to quantify chlorophyll a concentration.

openCC (other)Mar 2025View details →

Climate data for C1 data loggers (CR23X and CR1000), 2000 - ongoing, daily.

Climatological data were collected from the C1 climate station on Niwot Ridge (3018 m elevation) throughout the year. From 2000-06-24 to 2013-03-25, data were recorded using a Campbell Instruments CR23X data logger. Starting 2013-03-27, data were recorded using a Campbell Instruments CR1000 data logger. Maximum and minimum values were recorded instantaneously, with a sampling interval of 5 seconds. Daily means and totals were calculated from 17,280 individual measurements. The CR23X logger was programmed to generate both hourly and daily output. The CR1000 logger generated daily, hourly, and minute data until 2014-09-10, when these time periods were discontinued and only 10 minute raw data were collected.

openCC (other)Mar 2025View details →

Climate data for saddle data loggers (CR23X and CR1000), 2000 - ongoing, daily.

Climatological data were collected from the saddle climate station on Niwot Ridge (3525 m elevation) throughout the year. From 2000-06-24 to 2012-03-24, data were recorded using a Campbell Instruments CR23X data logger. Subsequently, data were recorded using a Campbell Instruments CR1000 data logger. Maximum and minimum values were recorded instantaneously, with a sampling interval of 5 seconds. Daily means and totals were calculated from 17,280 individual measurements. The CR23X logger was programmed to generate both hourly and daily output. The CR1000 logger generated daily, hourly, and minute data until September 2014, and 10 minute and minute data thereafter.

openCC (other)Aug 2021View details →

Florida Bay Braun Blanquet, Everglades National Park (FCE), South Florida from October 2000 to Present (Reformatted to the ecocomDP Design Pattern)

This data package is formatted as an ecocomDP (Ecological Community Data Pattern). For more information on ecocomDP see https://github.com/EDIorg/ecocomDP. This Level 1 data package was derived from the Level 0 data package found here: https://pasta.lternet.edu/package/metadata/eml/knb-lter-fce/1129/8. The abstract below was extracted from the Level 0 data package and is included for context: Braun Blanquet surveys determining frequency, abundance, and density for seagrass and macroalgae made during visits to TS/Ph 7a, 8-11. Our long term research program focuses on the following central objective: Regional processes mediated by water flow control population and ecosystem level dynamics at any location within the coastal Everglades landscape. This phenomenon is best exemplified in the dynamics of an estuarine oligohaline zone where fresh water draining phosphorus-limited Everglades marshes mixes with water from the more nitrogen-limited coastal ocean. Graphic representation of data can be located at http://serc.fiu.edu/seagrass/!CDreport/DataHome.htm We are investigating how variability in regional climate, freshwater inputs, disturbance, and perturbations affect the coastal Everglades ecosystem. Our long term research program focuses on testing the following central idea and hypotheses: Regional processes mediated by water flow control population and ecosystem level dynamics at any location within the coastal Everglades landscape. This phenomenon is best exemplified in the dynamics of an estuarine oligohaline zone where fresh water draining phosphorus-limited Everglades marshes mixes with water from the more nitrogen-limited coastal ocean. Hypothesis 1: In nutrient-poor coastal systems, long-term changes in the quantity or quality of organic matter inputs will exert strong and direct controls on estuarine productivity, because inorganic nutrients are at such low levels. Hypothesis 2: Interannual and long-term changes in freshwater flow controls the magnitude of nut

openCC (other)Jul 2025View details →

Above and below ground plant biomass in Arctic LTER's 1981 mesic acidic tussock tundra experimental site (MAT81) harvested in 2000, Arctic LTER, Toolik Lake, Alaska.

Above and below-ground plant biomass, including plant roots, was measured in Arctic LTER's moist acidic tussock tundra experimental site (MAT81). The plots were set up in 1981 and have been harvested in previous years (See Shaver and Chapin Ecological Monographs, 61(1), 1991 pp.1-31). This file contains the 2000 harvested biomass and percent carbon and nitrogen summaries for control and fertilized plots. Leaf area data for select species are available in Shaver, G. 2016. https://doi.org/10.6073/pasta/13915ef410067ef23bad0faff678319c

Paleolimnology of Lakes in Central New England from 2000 BP to Present

Paleolimnological studies of three small watersheds in central New England were undertaken to determine the influence of deforestation and agriculture on lake systems, as well as the response of the lakes to agricultural abandonment and reforestation, or the cessation of disturbance. Sites were chosen to represent a range of past land-use activities, while keeping other site factors constant. The study was designed to complement the historical and paleoecological studies of the central Massachusetts area of Fuller et al. (1998) and Foster et al. (1998). Changes in terrestrial vegetation were documented using the pollen record from each lake, and changes in aquatic systems were documented through fossil chironomid assemblages (Chironomidae: Diptera) and sediment chemistry. Dated cores were analyzed for pollen, fossil chironomids, percent organic matter, carbon and nitrogen, and sedimentation changes. Increased sedimentation rates occurred in all lakes during the settlement period, and small increases in productivity changes resulted from the increased runoff. Productivity changes, as indicated by organic material, C:N ratios, and chironomid assemblages, are more pronounced in North Round and Wickett Ponds than in Pecker Pond, even though agricultural activity was most intense at Pecker Pond. North Round and Wickett Ponds are more shallow than Pecker, and were more affected by sediment and nutrient inputs from the watershed. North Round Pond was the least impacted site, with only minimal logging and no agriculture, but still significant changes occurred during the settlement period. The sedimentation rates and productivity continue to be higher than pre-settlement levels, indicating that the systems have not returned to pre-disturbance states. This is similar to the response of forest vegetation studied by Fuller et al. (1998) in the Central Massachusetts study. The low intensity agricultural practices of the 19th Century and small watershed sizes contributed to the f

Long-term Vegetation Dynamics on the Massachusetts Coast from 2000 BP to Present

We use a retrospective approach to reconstruct the past distribution of fire in New England and to investigate the important drivers of this pattern across the period of European arrival to North America. Our study sites are in New England, and range from pitch pine and oak forests of coastal Massachusetts, pine and hardwood forests of central Massachusetts, and northern hardwood and spruce fir forests of northern Massachusetts and Vermont. We collected sediment profiles from 18 lakes across the study area to assess fossil charcoal and pollen abundance over the past 1000 years and including the time period of European arrival and settlement. Based on presettlement pollen composition, our study sites are divided into three vegetation types: 1) pitch pine and oak, 2) oak, pine, and hardwood, and 3) northern hardwoods. The abundance of presettlement charcoal in these lakes is closely related to climate and the composition of surrounding vegetation. Charcoal is most abundant in pitch pine forests and least common in northern hardwood and spruce forests. Following the arrival of Europeans, charcoal abundance increases, at most sites substantially, and vegetation composition changed in a direction of either greater dominance by pitch pine or white pine, depending on whether the forests were located in the southern or northern part of New England. The major factor influencing the distribution of fire across New England is climate, which has a direct effect on the physical conditions conducive to fire ignition and spread and an indirect effect on fire through its control on the distribution of vegetation at this spatial scale. We find evidence that other factors exert some control over local fire regimes as well including landforms and their impact on vegetation composition, firebreaks, and prevailing winds. Native Americans likely influenced the local occurrence of fire, but their impact on regional fire regimes in New England is not apparent from this or other studies. Ho

Lake Metabolism at North Temperate Lakes LTER 2000

Recent literature suggests that for many lakes and rivers, the respiratory breakdown of organic matter (R) exceeds production of organic matter by photosynthesis (gross primary production; GPP) within the water body. This metabolic balance (GPP less than R; heterotrophy ) implies that allochthonous organic matter supports a portion of the aquatic ecosystems respiration. Evidence that many lakes are heterotrophic comes from diverse approaches, and debate remains over the circumstances in which heterotrophy exists. The methods used to estimate GPP and R and the limited extent of lake types studied, especially with respect to dissolved organic carbon (DOC) and total phosphorus (TP) concentrations, are two reasons for differing conclusions. In this study, O2 and CO2 sondes were deployed during July and August, 2000 to measure diel gas dynamics in the surface waters of 25 lakes in the Northern Highland Lake district of Wisconsin and the Upper Peninsula of Michigan. The lakes were chosen to span wide and orthogonal ranges in DOC and TP concentrations. From these data, we calculated GPP, R and net ecosystem production (NEP=GPP-R). Over the broad range in TP and DOC among the lakes, diel CO2 and O2 changed on a near 1:1 molar ratio. Metabolism estimates from the two gases were comparable, except at high pH. Most lakes in our data set had -NEP, but GPP and R appeared to be controlled by different factors. TP correlated strongly with GPP, whereas DOC correlated with R. At low DOC concentrations, GPP and R were nearly equal, but at higher DOC, GPP and R uncoupled and lakes had -NEP. Strong correlations between lake metabolism and landscape related variables suggest that allochthonous carbon influences lake metabolism. Sampling Frequency: Chemical parameters and physical properties sampled from 1 to 4 times during the summer. Time series data step is 30 minutes. Number of sites: Time series data for 25 lakes. Chemical and physical data from 31 lakes.

Biocomplexity at North Temperate Lakes LTER; Coordinated Field Studies: Predation Study Data 2000 - 2004

These data were collected to track changes in dietary composition, changes in age and growth structure, and changes in species and size of prey of fish predators in Sparkling Lake, Vilas County, WI, USA. Sampling began in May of 2000 and ended in September of 2004. Fish were collected with a boat-mounted electrofishing system, usually by conducting a complete lap around Sparkling Lake shortly after dark. Commonly captured species were rock bass, smallmouth bass, and walleye. Less common species were pumpkinseed sunfish and yellow perch. Dietary Composition: Fish stomach contents were collected by gastric lavage, and fish were released after capture. Stomach contents were sorted and counted by major taxonomic groups, dried in polystyrene weighboats at 57 deg C for 48hrs, and then weighed to 0.001g. The count under a taxonomic group heading indicates how many individuals of that group were found in that diet sample. The mass of that group is given in the adjacent ''net wt'' column. Diets varied across sampling dates and years, with a trend towards decreased abundance of the exotics rusty crayfish and rainbow smelt and increased reliance on native minnows. Prey Data: Fish stomach contents were collected by gastric lavage, and fish were released after capture. Once collected, crayfish and fish prey were measured unless advanced digestion had occurred. If possible, the carapace, right chela and left chela of crayfish prey were measured . Due to digestion, it was usually not possible to get all three measurements. The total length of prey fish was recorded. Young-of-year smelt and crayfish were often too small or digested to measure; these were often just counted. Gut labels on each sampling date correspond with the same gut labels in other datasets. Prey fish and crayfish size and composition varied across sampling dates and years, with a trend towards decreased abundance of rusty crayfish and rainbow smelt and increased reliance on native minnows. Age Growth Data: Scale

Primary Production and Species Richness in Lake Communities 1997 - 2000

An understanding of the relationship between species richness and productivity is crucial to understanding biodiversity in lakes. We investigated the relationship between the primary productivity of lake ecosystems and the number of species for lacustrine phytoplankton, rotifers, cladocerans, copepods, macrophytes, and fish. Our study includes two parts: (1) a survey of 33 well-studied lakes for which data on six major taxonomic groups were available; and (2) a comparison of the effects of short- and long-term whole-lake nutrient addition on primary productivity and planktonic species richness Dodson, Stanley I., Shelley E. Arnott, and Kathryn L. Cottingham. 2000. The relationship in lake communities between primary productivity and species richness. Ecology 81:2662-79. Number of sites: 33

North Temperate Lakes LTER: Total Particulate Matter - Madison Lakes Area 2000 - 2013

Total particulate matter is measured at one station in the deepest part of each lake at the top of the epilimnion for lakes Mendota, Monona, Fish and Wingra. Sampling Frequency: bi-weekly during ice-free season from late March or early April through early September, then every 4 weeks through late November; sampling is conducted usually once during the winter (depending on ice conditions). Number of sites: 4

openCC (other)Dec 2022View details →

Little Rock Lake Experiment at North Temperate Lakes LTER: Nutrients 1996 - 2000

The Little Rock Acidification Experiment was a joint project involving the USEPA (Duluth Lab), University of Minnesota-Twin Cities, University of Wisconsin-Superior, University of Wisconsin-Madison, and the Wisconsin Department of Natural Resources. Little Rock Lake is a bi-lobed lake in Vilas County, Wisconsin, USA. In 1983 the lake was divided in half by an impermeable curtain and from 1984-1989 the northern basin of the lake was acidified with sulfuric acid in three two-year stages. The target pHs for 1984-5, 1986-7, and 1988-9 were 5.7, 5.2, and 4.7, respectively. Starting in 1990 the lake was allowed to recover naturally with the curtain still in place. Data were collected through 2000. The main objective was to understand the population, community, and ecosystem responses to whole-lake acidification. Funding for this project was provided by the USEPA and NSF. Parameters characterizing the nutrient chemistry of the treatment and reference basins of Little Rock Lake are measured at one station in the deepest part of each basin at the top and bottom of the epilimnion, mid-thermocline, and top, middle, and bottom of the hypolimnion. These parameters include total nitrogen, total dissolved nitrogen, nitrate, ammonia, total phosphorus, total dissolved phosphorus, dissolved reactive phosphorus, bicarbonite-reactive filtered and unfiltered silica, dissolved reactive silica, total inorganic carbon, dissolved inorganic carbon, total organic carbon, dissolved organic carbon, and total particulate matter. Sampling Frequency: varies - Number of sites: 2