نتایج جستجو برای: representative watersheds

تعداد نتایج: 92866  

2009
Dale M Robertson Gregory E Schwarz David A Saad Richard B Alexander

Excessive loads of nutrients transported by tributary rivers have been linked to hypoxia in the Gulf of Mexico. Management efforts to reduce the hypoxic zone in the Gulf of Mexico and improve the water quality of rivers and streams could benefit from targeting nutrient reductions toward watersheds with the highest nutrient yields delivered to sensitive downstream waters. One challenge is that m...

Journal: :Environmental science & technology 2017
Fabian Nippgen Matthew R V Ross Emily S Bernhardt Brian L McGlynn

Mountaintop removal coal mining (MTM) is a form of surface mining where ridges and mountain tops are removed with explosives to access underlying coal seams. The crushed rock material is subsequently deposited in headwater valley fills (VF). We examined how this added water storage potential affects streamflow using a paired watershed approach consisting of two sets of mined and unmined watersh...

Journal: :Ecological Indicators 2022

Water temperature is an abiotic master variable for the survival of aquatic organisms. Global warming alters thermal regimes rivers and, thus, poses a threat to freshwater biodiversity. To address impacts water changes related global on fish species in life cycle assessment (LCA), we developed spatially explicit characterization factors (CFs) 207 greenhouse gases under four representative conce...

2011
Daniel R Wise Henry M Johnson

The SPAtially Referenced Regressions On Watershed attributes (SPARROW) model was used to perform an assessment of surface-water nutrient conditions and to identify important nutrient sources in watersheds of the Pacific Northwest region of the United States (U.S.) for the year 2002. Our models included variables representing nutrient sources as well as landscape characteristics that affect nutr...

2011
S. Amri W. Barhoumi E. Zagrouba

The proposed approach aims to track multiple moving people in a colour video acquired with a single camera. The first phase of the approach consists in precisely detecting multi-human inside moving foregrounds. The input to this phase is foreground pixels which were extracted from the scene using any background subtraction technique. These moving foregrounds are then further segmented into mult...

2015
Scott Bauer Jennifer Olson Adam Cockrill Michael van Hattem Linda Miller Margaret Tauzer Gordon Leppig

Marijuana (Cannabis sativa L.) cultivation has proliferated in northwestern California since at least the mid-1990s. The environmental impacts associated with marijuana cultivation appear substantial, yet have been difficult to quantify, in part because cultivation is clandestine and often occurs on private property. To evaluate the impacts of water diversions at a watershed scale, we interpret...

1999
T. A. Cochrane

Two different methods utilizing geographical information systems (GIS) and digital elevation models (DEMs) are described and evaluated for applying the Water Erosion Prediction Project (WEPP) model to assess water erosion and runoff in small watersheds. The first approach, called the Hillslope method, presents an automated method for the application of WEPP through the extraction of hillslopes ...

2005
John A. Moody David A. Kinner

Predicting runoff and erosion from watersheds burned by wildfires requires an understanding of the spatial structure of both hillslope and channel drainage networks. We investigate the small-scale and large-scale structures of drainage networks using field studies and computer analysis of 30-m digital elevation model. Topologic variables were derived from a composite 30-m DEM, which included 14...

Journal: :Journal of environmental quality 2007
X Wang A Saleh M W McBroom J R Williams L Yin

Hydrologic/water quality models are increasingly used to explore management and policy alternatives for managing water quality and quantity from intensive silvicultural practices with best management practices (BMPs) in forested watersheds due to the limited number of and cost of conducting watershed monitoring. The Agricultural Policy/Environmental eXtender (APEX) model was field-tested using ...

2015
E. Terrence Slonecker Lesley E. Milheim

The spatial footprint of unconventional (hydraulic fracturing) and conventional oil and gas development in the Marcellus Shale region of the State of Pennsylvania was digitized from high-resolution, ortho-rectified, digital aerial photography, from 2004 to 2010. We used these data to measure the spatial extent of oil and gas development and to assess the exposure of the extant natural resources...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید