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Abstract: We report on net ecosystem production (NEP) and key environmental controls on net ecosystem exchange (NEE) of carbon dioxide (CO 2 ) between a mangrove forest and the atmosphere in the coastal Florida Everglades. An eddy covariance system deployed above the canopy was used to determine NEE during January 2004 through August 2005. Maximum daytime NEE ranged from −20 to −25 μ mol (CO 2 ) m −2 s −1 between March and May. Respiration (R d ) was highly variable (2.81 ± 2.41 μ mol (CO 2 ) m −2 s −1 ), reaching peak values during the summer wet season. During the winter dry season, forest CO 2 assimilation increased with the proportion of diffuse solar irradiance in response to greater radiative transfer...
Abstract (from http://onlinelibrary.wiley.com/doi/10.1111/jawr.12179/abstract): Freshwater mussels (order Unionida) are a highly imperiled group of organisms that are at risk from rising stream temperatures ( T ). There is a need to understand the potential effects of land use (LU) and climate change (CC) on stream T and have a measure of uncertainty. We used available downscaled climate projections and LU change simulations to simulate the potential effects on average daily stream T from 2020 to 2060. Monte Carlo simulations were run, and a novel technique to analyze results was used to assess changes in hydrologic and stream T response. Simulations of daily mean T were used as input to our stochastic...
Abstract (from http://sp.lyellcollection.org/content/early/2015/10/09/SP408.11.abstract): We present a hierarchical series of spatially decreasing and temporally increasing models to evaluate the uncertainty in the atmosphere – ocean global climate model (AOGCM) and the regional climate model (RCM) relative to the uncertainty in the somatic growth of the endangered pallid sturgeon (Scaphirhynchus albus). For effects on fish populations of riverine ecosystems, climate output simulated by coarse-resolution AOGCMs and RCMs must be downscaled to basins to river hydrology to population response. One needs to transfer the information from these climate simulations down to the individual scale in a way that minimizes extrapolation...
[Excerpt from Introduction] "The San Francisco Bay Estuary supports a large and diverse bird community. More than 50% of most Pacific flyway diving duck populations are found in the Estuary during the winter months (Trost 2002; U.S. Fish and Wildlife Service 2002). San Francisco Bay has been designated as a site of international importance for shorebirds (Western Hemisphere Shorebird Reserve Network), supporting millions of individuals (Morrison et al. 2001; Takekawa et al. 2001; Warnock et al. 2002), including species that use tidal marsh habitats. In total, the Bay’s tidal marshes support at least 113 bird species that represent 31 families (Takekawa et al., in press)..."
Abstract (from http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0138759): Future climate change may significantly alter the distributions of many plant taxa. The effects of climate change may be particularly large in mountainous regions where climate can vary significantly with elevation. Understanding potential future vegetation changes in these regions requires methods that can resolve vegetation responses to climate change at fine spatial resolutions. We used LPJ, a dynamic global vegetation model, to assess potential future vegetation changes for a large topographically complex area of the northwest United States and southwest Canada (38.0–58.0°N latitude by 136.6–103.0°W longitude). LPJ is a...
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This dataset includes electrical resistance data from a network of 50 data loggers that was installed throughout the Willow-Whitehorse watershed of SE Oregon in September 2014. Data loggers were downloaded in August 2015 and September 2016. These data loggers were used as “electrical resistance” (ER) sensors, following Chapin et al. 2014. The sensors were Onset HOBO Pendant temperature data loggers that were modified to monitor streamflow intermittency and determine the timing of stream drying.
The Hawaiian Islands' largest atoll, French Frigate Shoals, is key to understanding how seabird nesting habitat will change with predicted rising sea levels.
Abstract (from http://onlinelibrary.wiley.com/doi/10.1002/ecy.1853/full): Predicting species responses to perturbations is a fundamental challenge in ecology. Decision makers must often identify management perturbations that are the most likely to deliver a desirable management outcome despite incomplete information on the pattern and strength of food web links. Motivated by a current fishery decline in inland lakes of the Midwestern United States, we evaluate consistency of the responses of a target species (walleye (Sander vitreus)) to press perturbations. We represented food web uncertainty with 196 plausible topological models and applied four perturbations to each one. Frequently the direction of the focal...
Board Game, Species Information Cards, and Spinner Template for "Migration Mismatch" board game.
We classified walleye ( Sander vitreus) recruitment with 81% accuracy (recruitment success and failure predicted correctly in 84% and 78% of lake-years, respectively) using a random forest model. Models were constructed using 2779 surveys collected from 541 Wisconsin lakes between 1989 and 2013 and predictor variables related to lake morphometry, thermal habitat, land use, and fishing pressure. We selected predictors to minimize collinearity while maximizing classification accuracy and data availability. The final model classified recruitment success based on lake surface area, water temperature degree-days, shoreline development factor, and conductivity. On average, recruitment was most likely in lakes larger than...
Abstract (from http://link.springer.com/article/10.1007/s10236-013-0684-3): A three-level nested Regional Ocean Modeling System was used to examine the seasonal evolution of the Copper River (CR) plume and how it influences the along- and across-shore transport in the northern Gulf of Alaska (NGoA). A passive tracer was introduced in the model to delineate the growth and decay of the plume and to diagnose the spread of the CR discharge in the shelf, into Prince William Sound (PWS) and offshore. Furthermore, a model experiment with doubled discharge was conducted to investigate potential impacts of accelerated glacier melt in future climate scenarios. The 2010 and 2011 simulation revealed that the upstream (eastward)...
This catalog contains Geographic Information System (GIS) data in georeferenced vector (point) and raster formats. The vector (point) data are available as Environmental Systems Research Institute (ESRI) shapefiles and as comma-separated text (*.csv) files. Shapefiles generally include *.shp, *.shx, *.xml, and *.dbf files at a minimum. All these data files also include the *.prj files, which contain the dataset projection information. The corresponding 4-km resolution raster data are available in Imagine *.img format. The GIS files have been bundled by year. Each year of raster data (GRID-type) has an associated compressed WinRAR zip file. The corresponding shp and csv data types have compressed WinRAR RAR files,...
Our knowledge of avian behaviors during the non-breeding period still lags behind that of the breeding season, but the last decade has witnessed a proliferation in research that has yielded significant progress in understanding migration patterns of North American birds. And, although the great majority of migration research has historically been conducted in the eastern half of the continent, there has been much recent progress on aspects of avian migration in the West. In particular, expanded use of techniques such as radar, plasma metabolites, mist-netting, count surveys, stable isotopes, genetic data, and animal tracking, coupled with an increase in multi-investigator collaborations, have all contributed to...
Abstract (from http://link.springer.com/article/10.1007%2Fs10980-015-0160-1): Content Changing aspen distribution in response to climate change and fire is a major focus of biodiversity conservation, yet little is known about the potential response of aspen to these two driving forces along topoclimatic gradients. Objective This study is set to evaluate how aspen distribution might shift in response to different climate-fire scenarios in a semi-arid montane landscape, and quantify the influence of fire regime along topoclimatic gradients. Methods We used a novel integration of a forest landscape succession and disturbance model (LANDIS-II) with a fine-scale climatic water deficit approach to simulate dynamics of...
Density estimates of four mammal species in the upper subalpine and alpine zones of the Sierra Nevada range, 2008 - 2012. The estimates were derived from variable distance data collected 3-4 per year along each of 21 transects (10 km in length). The transects were randomly selected from a pool of 53 potential routes. Nine transects were sampled in 2008, 12 were sampled in 2009, 19 were sampled in 2010, 21 were sampled in 2011, and 17 were sampled in 2012. All counts were done in July and August each year. Replicate samples within a given year were done within 2-8 days of each other. All counts were done by single observers. The spreadsheet has six worksheets, including three with density estimates for each species...
map background search result map search result map Electrical resistance data from the Willow-Whitehorse watersheds of southeast Oregon, USA, 2014-2016 Electrical resistance data from the Willow-Whitehorse watersheds of southeast Oregon, USA, 2014-2016