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Summary 1. Historically, biogeographic barriers to the movement of aquatic organisms existed at multiple spatial scales and contributed to the development of unique regional faunas. At increasing spatial scales, these barriers consisted of waterfalls and cascades; catchment divides; major mountain ranges and oceans. This hierarchy of movement barriers produced increasingly distinct aquatic biotas at larger drainage units. 2. Humans have provided a variety of pathways by which aquatic species can circumvent historical biogeographic barriers. These include both authorised and unauthorised stocking, construction of canals and water conveyance systems, transport in ship ballast water, fishing and angling gear (including...
The U.S. Department of Energy initiated a remedial investigation of the Clinch River/Poplar Creek system Superfund Site in 1989. This site, located in eastern Tennessee near Oak Ridge, consists of 70 river kilometers and 40 km(2) of surface area. The purpose of this study was to evaluate the nature and extent of contamination, perform an ecological and human health risk assessment, and evaluate possible remedial alternatives. This introductory article summarizes the environmental setting, the contamination history, and the study approach and provides some general results of the site characterization. Subsequent papers in this series describe the ecological risks to fish, piscivorous and insectivorous wildlife, and...
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Within the time frame of the longevity of tree species, climate change will change faster than the ability of natural tree migration. Migration lags may result in reduced productivity and reduced diversity in forests under current management and climate change. We evaluated the efficacy of planting climate-suitable tree species (CSP), those tree species with current or historic distributions immediately south of a focal landscape, to maintain or increase aboveground biomass, productivity, and species and functional diversity. We modeled forest change with the LANDIS-II forest simulation model for 100 years (2000–2100) at a 2-ha cell resolution and five-year time steps within two landscapes in the Great Lakes region...
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Grasslands comprise a small part of the Chihuahuan Desert but are vital to the biological diversity of the ecoregion. Characteristic grasses of the Chihuahuan Desert are tobosa (Pleuraphis mutica) and black grama (Bouteloua eriopoda) but other common species include alakali sacaton (Sporobolus airoides), big alkali sacaton (S. wrightii), mesa dropseed (S. flexuosus), blue grama (B. gracilis), sideoats grama (B. curtipendula ), hairy grama (B. hirsuta), slender grama (B. filiformis), chino grama (B. brevista), spruce top grama (B. chondrosioides), bush muhly (Muhlenbergia porteri), several three awns (Aristida spp.), and fluff grass (Dasyochloa pulchela) (Johnson 1974, Dinerstein et al. 2000). Many of the sites discussed...
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Northeast Region Marsh Migration is one of a suite of products from the Nature’s Network project. Based on sea level rise (SLR) analysis by NOAA, this dataset depicts potential marsh migration zones at various sea level rise scenarios from 0-6’. Identification of suitable uplands adjacent to tidal wetlands is based on topography, habitat type, land use, and development, and can be used for facilitating marsh migration through land protection and/or management. The NOAA Coastal Change Analysis Program (CCAP) mapped the initial (current) distribution of potential marshes and and other coastal land cover types. The Detailed Method for Mapping Sea Level Rise Marsh Migration provides the full methodology for the data...
The U.S. Department of Energy initiated a remedial investigation of the Clinch River/Poplar Creek system Superfund Site in 1989. This site, located in eastern Tennessee near Oak Ridge, consists of 70 river kilometers and 40 km(2) of surface area. The purpose of this study was to evaluate the nature and extent of contamination, perform an ecological and human health risk assessment, and evaluate possible remedial alternatives. This introductory article summarizes the environmental setting, the contamination history, and the study approach and provides some general results of the site characterization. Subsequent papers in this series describe the ecological risks to fish, piscivorous and insectivorous wildlife, and...
The U.S. Department of Energy initiated a remedial investigation of the Clinch River/Poplar Creek system Superfund Site in 1989. This site, located in eastern Tennessee near Oak Ridge, consists of 70 river kilometers and 40 km(2) of surface area. The purpose of this study was to evaluate the nature and extent of contamination, perform an ecological and human health risk assessment, and evaluate possible remedial alternatives. This introductory article summarizes the environmental setting, the contamination history, and the study approach and provides some general results of the site characterization. Subsequent papers in this series describe the ecological risks to fish, piscivorous and insectivorous wildlife, and...
Dams are ubiquitous in coastal regions and have altered stream habitats and the distribution and abundance of stream fishes in those habitats by disrupting hydrology, temperature regime and habitat connectivity. Dam removal is a common restoration tool, but often the response of the fish assemblage is not monitored rigorously. Sedgeunkedunk Stream, a small tributary to the Penobscot River (Maine, USA), has been the focus of a restoration effort that includes the removal of two low-head dams. In this study, we quantified fish assemblage metrics along a longitudinal gradient in Sedgeunkedunk Stream and also in a nearby reference stream. By establishing pre-removal baseline conditions and associated variability and...
Abstract (from http://www.sciencedirect.com/science/article/pii/S1470160X15005518): Although localized effects of individual dams on stream fish assemblages have been relatively well-studied, less is known about the effects of multiple dams within a stream network on fishes and the patterns that emerge when the combined effects of individual and multiple dams are viewed across entire river basins, ecoregions, and states. This study evaluated multiple stream network fragmentation metrics representing localized (e.g., distance-to-dams) and cumulative (e.g., total upstream reservoir storage) dam influences on streams in Michigan, Wisconsin, and Minnesota, developing an approach for identifying suitable fish indicators...
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Establishing connections among natural landscapes is the most frequently recommended strategy for adapting management of natural resources in response to climate change. The U.S. Northern Rockies still support a full suite of native wildlife, and survival of these populations depends on connected landscapes. Connected landscapes support current migration and dispersal as well as future shifts in species ranges that will be necessary for species to adapt to our changing climate. Working in partnership with state and federal resource managers and private land trusts, we sought to: 1) understand how future climate change may alter habitat composition of landscapes expected to serve as important connections for wildlife,...
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Establishing connections among natural landscapes is the most frequently recommended strategy for adapting management of natural resources in response to climate change. The U.S. Northern Rockies still support a full suite of native wildlife, and survival of these populations depends on connected landscapes. Connected landscapes support current migration and dispersal as well as future shifts in species ranges that will be necessary for species to adapt to our changing climate. Working in partnership with state and federal resource managers and private land trusts, we sought to: 1) understand how future climate change may alter habitat composition of landscapes expected to serve as important connections for wildlife,...
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Establishing connections among natural landscapes is the most frequently recommended strategy for adapting management of natural resources in response to climate change. The U.S. Northern Rockies still support a full suite of native wildlife, and survival of these populations depends on connected landscapes. Connected landscapes support current migration and dispersal as well as future shifts in species ranges that will be necessary for species to adapt to our changing climate. Working in partnership with state and federal resource managers and private land trusts, we sought to: 1) understand how future climate change may alter habitat composition of landscapes expected to serve as important connections for wildlife,...
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This dataset is the output of a python script/ArcGIS model that identifes dikes as having a difference in elevation above a certain threshold. If the elevation difference was below a certain threshold the area was not considered a dike; however, if the difference in elevation between two points was significantly high then the area was marked as a dike. Areas continuous with eachother were considered part of the same dike. Post processing occured. Users examined the data output, comparing the proposed dike locations to aerial imagery, flowline data, and the DEM. Dikes that appeared to be false positives were deleted from the data set.
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Grasslands of the Sky Islands region once covered over 13 million acres in southeastern Arizona and adjacent portions of New Mexico, Sonora, and Chihuahua. Attempts to evaluate current ecological conditions suggest that approximately two thirds of these remain as intact or restorable grassland habitat. These grasslands provide watershed services such as flood control and aquifer recharge across the region, and continue to support dozens of species of concern. Prioritizing conservation interventions for these remaining grassland blocks has been challenging. Reliable data on condition and conservation value of grasslands in the region have not been systematically summarized. State and national boundaries further complicate...
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Within the time frame of the longevity of tree species, climate change will change faster than the ability of natural tree migration. Migration lags may result in reduced productivity and reduced diversity in forests under current management and climate change. We evaluated the efficacy of planting climate-suitable tree species (CSP), those tree species with current or historic distributions immediately south of a focal landscape, to maintain or increase aboveground biomass, productivity, and species and functional diversity. We modeled forest change with the LANDIS-II forest simulation model for 100 years (2000–2100) at a 2-ha cell resolution and five-year time steps within two landscapes in the Great Lakes region...
Synopsis: This paper aimed to quantify the relative importance of habitat area and configuration, as well as the contrast in resistance between habitat and non-habitat, on genetic differentiation patterns. Using spatially explicit, individual-based simulation modeling, researchers found that habitat configuration had stronger relationships with genetic differentiation than did habitat area. The pattern of habitat in a landscape will affect the distribution of the population and the degree of connectivity across it, resulting in differential patterns of gene flow. Researchers also evaluated the predictive ability of six widely used landscape metrics and found that patch cohesion and correlation length of habitat...
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Synopsis: This report evaluates habitat requirements of the American badger according to parameters of soil texture, graminoid cover, slope, and proximity to roads. Badgers tend to prefer sandy loam and silty loam, medium and moderately coarse textured soils. In terms of graminoid coverage, badgers generally prefer open grassland habitat, but can also be found in agriculturally dominated landscapes containing isolated pockets of Richardson 's ground squirrel colonies. Graminoid coverage of 23% was chosen as the minimum requirement for suitable badger habitat. As slope increases, habitat suitability decreases to a point at which the likelihood of badgers existing there (i.e. cliffs and badlands) is extremely low...
Regional transport of water and dissolved constituents through heavily regulated river systems is influenced by the presence of reservoirs. Analysis of seasonal patterns in solute fluxes for salinity and nutrients indicates that in-reservoir processes within large storage reservoirs in the Rio Grande and Colorado basins (southwestern USA) are superimposed over the underlying watershed processes that predominate in relatively unregulated stream reaches. Connectivity of the aquatic system with the landscape is apparently disrupted by processes within the reservoir systems; these processes result in large changes in characteristics for solute transport that persist downstream in the absence of significant inputs. Additionally,...
In this article, diverse liquid biofuels of the first generation were compared as partial or infant substitutes for fossil diesel fuel applied in cogeneration plant of the average capacity of 340 kW. The study concentrates on agricultural and economic conditions as well as legislative basis distinctive to Lithuania. At the laboratory of the Lithuanian University of Agriculture Institute of Agro-Engineering an experimental diesel engine powered generator was fuelled with rapeseed oil methyl ester (pure and in the blend with fossil diesel and dyed diesel fuels) and rapeseed oil with excellent energy balances and emissions characteristics more favorable than fossil diesel. Detailed estimations were proposed in order...
Landscape connectivity is critical to species persistence in the face of habitat loss and fragmentation. Graph theory is a well-defined method for quantifying connectivity that has tremendous potential for ecology, but its application has been limited to a small number of conservation scenarios, each with a fixed proportion of habitat. Because it is important to distinguish changes in habitat configuration from changes in habitat area in assessing the potential impacts of fragmentation, we investigated two metrics that measure these different influences on connectivity. The first metric, graph diameter, has been advocated as a useful measure of habitat configuration. We propose a second area-based metric that combines...
map background search result map search result map American Badger. Status and Distribution of Chihuahuan Desert Grasslands in the United States and Mexico Sustaining the Grassland Sea Connecting River Systems Restoration Assessment Dikes Potential climate change impacts on bighorn sheep connectivity in the U.S. Northern Rockies Potential climate change impacts on forest connectivity in the U.S. Northern Rockies Potential climate change impacts on mountain goat connectivity in the U.S. Northern Rockies Marsh Migration Zones, Northeast U.S. Publication: Measuring and managing resistance and resilience under climate change in northern Great Lake forests Publication: Climate change effects on northern Great Lake (USA) forests: A case for preserving diversity Connecting River Systems Restoration Assessment Dikes American Badger. Sustaining the Grassland Sea Potential climate change impacts on bighorn sheep connectivity in the U.S. Northern Rockies Potential climate change impacts on forest connectivity in the U.S. Northern Rockies Potential climate change impacts on mountain goat connectivity in the U.S. Northern Rockies Marsh Migration Zones, Northeast U.S. Publication: Measuring and managing resistance and resilience under climate change in northern Great Lake forests Publication: Climate change effects on northern Great Lake (USA) forests: A case for preserving diversity Status and Distribution of Chihuahuan Desert Grasslands in the United States and Mexico