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Summary Analysis of historical streamflow trends and their relationship to landscape characteristics is essential for understanding geographic differences in runoff within the Great Lakes basin and for distinguishing temporal trends from temporal variance. Factor analysis of streamflow records (1956–1988) from 32 US Geological Survey gauging stations within the Great Lakes basin revealed distinct spatio-temporal patterns of stream runoff within five different regions of the basin. Streams represented by the first annual factor occurred in southern Wisconsin and the lower peninsula of Michigan, and exhibited a linear increase in mean annual streamflow over the 33 year period caused by increased autumn and winter...
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Natural landscapes in the Southwestern United States are changing. In recent decades, rising temperatures and drought have led to drier conditions, contributed to large-scale ecological impacts, and affected many plant and animal species across the region. The current and future trajectory of climate change underscores the need for managers and conservation professionals to understand the impacts of these patterns on natural resources. In this regional assessment of the Southwest Climate Change Initiative, we evaluate changes in annual average temperatures from 1951–2006 across major habitats and large watersheds and compare these changes to the number of species of conservation concern that are found within these...
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Final Report - Executive Summary: This final project report is prepared to summarize the research project titled “Assessing evapotranspiration rate changes for proposed restoration of the forested uplands of the Desert Landscape Conservation Cooperatives (LCC)” for the Desert LCC of the Bureau of Reclamation as a requirement for closing out the project. This report includes the scope of work, summary of research project, results, and conclusions.Among all of the components of the terrestrial water cycle, evapotranspiration (ET) consumes the largest amount of water. Accurate estimation of ET is very important to understand the influence of ET to the hydrologic response of recharge and runoff processes in the water...
Categories: Data, Publication; Types: Citation, Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: 2012, ATMOSPHERE, ATMOSPHERE, ATMOSPHERIC WATER VAPOR, ATMOSPHERIC WATER VAPOR, All tags...
The small watershed approach is well-suited but underutilized in mercury research. We applied the small watershed approach to investigate total mercury (THg) and methylmercury (MeHg) dynamics in streamwater at the five diverse forested headwater catchments of the US Geological Survey Water, Energy, and Biogeochemical Budgets (WEBB) program. At all sites, baseflow THg was generally less than 1 ng L−1 and MeHg was less than 0.2 ng L−1. THg and MeHg concentrations increased with streamflow, so export was primarily episodic. At three sites, THg and MeHg concentration and export were dominated by the particulate fraction in association with POC at high flows, with maximum THg (MeHg) concentrations of 94 (2.56) ng L−1...
Quantifying and evaluating effects of best management practices (BMPs) on water quality is necessary to maximize the effectiveness of BMPs for minimizing pollutants. Watershed-scale evaluation of effects of BMP implementation on fecal bacteria and sediment yield can be estimated using a watershed water quality model, and strategies for identifying critical areas in a watershed can be pollutant specific. The soil and water assessment tool (SWAT) model was used in the Upper Wakarusa watershed (950 km2) in northeast Kansas to explore effectiveness of vegetative filter strip (VFS) lengths applied at the edge of fields to reduce non-point source pollution. The Upper Wakarusa watershed is a high priority total maximum...
Summary Non-point nitrogen (N) loss from agriculture is an environmental concern among scientists, decision-makers, and the public. This study investigated NO3–N and total N losses from a mixed land use watershed (39.5 ha) in the Appalachian Valley and Ridge Physiographic Province as influenced by hydrology (flow type, runoff volume, storm sizes, and precipitation amount) and seasons (pre-growing, growing, and post-growing seasons) from 2002 to 2006. Stream discharge was monitored every 5-min and water samples for NO3–N and total N analyses were collected weekly for base flow and for every storm. The majority of NO3–N (about 75%) and total N (about 65%) were exported in base flow, which contributed about 64% of...
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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...
Conclusions:Within a watershed, about 10% of development is not subject to drainage regulations resulting in cumulative effects from urbanization that significantly degrade watersheds. Instead of regulatory thresholds (e.g. 10% EIA), process controls are required to mitigate the impacts of urbanization on aquatic systems. Without these controls, strict development limits are the only way to limit watershed degradation.Thresholds/Learnings:The study cautions against the use of discrete “thresholds” to predict specific physical and biological effects, but does suggest that thresholds are appropriate indicators for when the perception and tolerance of watershed impacts triggers a regulatory response.
The development and the application of ArcCN-Runoff tool, an extension of ESRI@ ArcGIS software, are reported. This tool can be applied to determine curve numbers and to calculate runoff or infiltration for a rainfall event in a watershed. Implementation of GIS techniques such as dissolving, intersecting, and a curve-number reference table improve efficiency. Technical processing time may be reduced from days, if not weeks, to hours for producing spatially varied curve number and runoff maps. An application example for a watershed in Lyon County and Osage County, Kansas, USA, is presented.
Summary Non-point nitrogen (N) and phosphorus (P) pollution from agriculture has increasingly received more public attention. In this study, NO3–N, dissolved P (DP) and particulate P (PP) concentrations and loads were investigated for four sub-basins (labeled 1–4 going up the watershed) within a mixed land use watershed (39.5 ha) in the Appalachian Valley and Ridge Physiographic Province. The hot moments of NO3–N concentration and load occurred in base flow and during the non-growing season. Great and temporally variable DP and PP concentrations were observed in storm flow. The hot moments of DP concentration and load were in storm flow from May to December and from September to Nov, respectively, while the hot...
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Riparian grasslands dominated by big sacaton (Sporobolus wrightii) once covered floodplains across the southwest, but have been reduced to some 5% of their historical extent. Sacaton stands that remain provide key resources for watershed function, wildlife, and livestock—yet may need special management to sustain these benefits. This report describes mapping methods and management recommendations that can be applied to riparian grasslands throughout the region. By examining sacaton grasslands in the Las Cienegas National Conservation Area, this project also refines methods for evaluating ecological condition, and provides managers at this site with detailed maps of both high-quality habitat and restoration needs.
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NatureServe worked with several federal, state, and NGO partners in the United States and Mexico to conduct a climate change vulnerability assessment of major natural community types found within the Mojave and Sonoran Deserts. The project focused on ten major upland, riparian, and aquatic community types, including pinyon-juniper woodlands, Joshua tree-blackbrush scrub, creosote-bursage scrub, salt desert scrub, Paloverde-mixed cacti scrub, semi-desert grassland, desert riparian and stream, riparian mesquite bosque, and desert springs. This effort piloted a new Habitat Climate Change Vulnerability Index (HCCVI) approach being developed by NatureServe, as a companion to an existing index for species. The project...
In the Central Rocky Mountains, snowfall dominates precipitation. Airborne contaminants retained in the snowpack can affect high elevation surface water chemistry during snowmelt. At the Fraser Experimental Forest (FEF), located west of the Continental Divide in Central Colorado, snowmelt dominates the annual hydrograph, and accounts for >95% of annual stream water discharge. During the winters of 1989?1993, we measured precipitation inputs, snowpack water equivalent (SWE) and ion content, and stream water chemistry every 7?10 days along a 3150?3500 m elevation gradient in the subalpine and alpine Lexen Creek watershed. The study objectives were to (1) quantify the distribution of SWE and snowpack chemical content...
In an effort to develop indicators for Great Lakes near-shore conditions, diatom-based transfer functions to infer water quality variables were developed from 155 samples collected from coastal Great Lakes wetlands, embayments and high-energy shoreline sites. Over 2,000 diatom taxa were identified, and 352 taxa were sufficiently abundant to include in transfer function development. Multivariate data exploration revealed strong responses of the diatom assemblages to stressor variables, including total phosphorus (TP). Spatial variables such as lake, latitude and longitude also had notable relationships with assemblage characteristics. A diatom inference transfer function for TP provided a robust reconstructive relationship...
Agriculture is the leading source of nonpoint-source pollution on a national scale. the driving force of nonpoint-source pollution is the rainfall-runoff process, which is the transformation of rainfall to streamflow. This is a complex, nonlinear, time-varying, and spatially distributed process on the watershed scale that is difficult to effectively model by conventional, deterministic means. Artificial neural networks (ANNs) offer a new approach to forecasting the hydrologic and water quality response of a watershed system. The goal of this work is to develop an ANN model as a long-term forecuating tool for predicting the hydrology and water quality of agricultural watersheds where the physical processes are difficult...
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Conclusions: Prescribed burns did not supply the stream ecosystem with potentially important nutrient pulses that are often observed after wildfires. Prescribing higher severity burns to more closely mimic wildfires would enhance N cycling in productivity in N-limited headwater watersheds. Thresholds/Learnings: Synopsis: This study aimed to compare the short-term effects of spring prescribed burns and wildfires on Nitrogen cycling dynamics in headwater watersheds of central Idaho. Fire affected N dynamics in both terrestrial and aquatic components of the watershed ecosystem after wildfires but were limited to the terrestrial ecosystem after prescribed burns. Streamwater NO3 concentrations were affected significantly...
The small watershed approach is well-suited but underutilized in mercury research. We applied the small watershed approach to investigate total mercury (THg) and methylmercury (MeHg) dynamics in streamwater at the five diverse forested headwater catchments of the US Geological Survey Water, Energy, and Biogeochemical Budgets (WEBB) program. At all sites, baseflow THg was generally less than 1 ng L−1 and MeHg was less than 0.2 ng L−1. THg and MeHg concentrations increased with streamflow, so export was primarily episodic. At three sites, THg and MeHg concentration and export were dominated by the particulate fraction in association with POC at high flows, with maximum THg (MeHg) concentrations of 94 (2.56) ng L−1...
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This report is volume 2 of a two-volume ecological assessment of grassland ecosystems in the Southwestern United States. Broad-scale assessments are syntheses of current scientific knowledge, including a description of uncertainties and assumptions, to provide a characterization and comprehensive description of ecological, social, and economic components within an assessment area. Volume 1 of this assessment focused on the ecology, types, conditions, and management practices of Southwestern grasslands. Volume 2 (this volume) describes wildlife and fish species, their habitat requirements, and species-specific management concerns, in Southwestern grasslands. This assessment is regional in scale and pertains primarily...
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Most groundwater conservation and management efforts focus on protecting groundwater for drinking water and for other human uses with little understanding or focus on the ecosystems that depend on groundwater. However, groundwater plays an integral role in sustaining certain types of aquatic, terrestrial and coastal ecosystems, and their associated landscapes. Our aim was to illuminate the connection between groundwater and surface ecosystems by identifying and mapping the distribution of groundwater dependent ecosystems (GDEs) in California. This layer includes watersheds from the Watershed Boundary Database at the 12-digit hydrologic unit code (HUC12) scale. Each watershed is attributed with summary information...


map background search result map search result map Effects of spring prescribed burning and wildfires on watershed nitrogen dynamics of central Idaho headwater areas Climate Change Vulnerability and Adaptation Strategies for Natural Communities Sustaining the Grassland Sea Assessment of Grassland Ecosystem Conditions in the Southwestern United States: Wildlife and Fish, Volume 2 Managing Changing Landscapes in the Southwestern United States Sacaton Riparian Grasslands Mapping Groundwater Dependent Ecosystems in California Report and Publications: Assessing Evapotranspiration Rate Changes for Proposed Restoration of the Forested Uplands of the DLCC Sacaton Riparian Grasslands Effects of spring prescribed burning and wildfires on watershed nitrogen dynamics of central Idaho headwater areas Sustaining the Grassland Sea Report and Publications: Assessing Evapotranspiration Rate Changes for Proposed Restoration of the Forested Uplands of the DLCC Climate Change Vulnerability and Adaptation Strategies for Natural Communities Mapping Groundwater Dependent Ecosystems in California Managing Changing Landscapes in the Southwestern United States Assessment of Grassland Ecosystem Conditions in the Southwestern United States: Wildlife and Fish, Volume 2