The catchment, or catchment area, is the area associated with a segment of a drainage network. Surface runoff in a catchment flows into the associated network segment. Catchment area is commonly used for estimating watershed parameters, such as upstream drainage area, flood frequency, or surface-water flow. Hydrologic analyses require relatively accurate catchment area estimates to furnish subs...

The mean annual transfer (loss and retention) of nitrogen in a river system was estimated using a conceptual approach based on water surface area and runoff. Two different approaches for the calculation of water surface area were applied to determine riverine nitrogen retention in four European catchments, ranging between 860-14,000 km2 in area, and differing considerably in the proportion and ...

An acid waters sensitivity map has been widely used as a background resource for assessing potential impacts of forest management on stream water acidity within Wales. The validity of this approach has been explored by comparing predicted acid sensitivity with the observed acid neutralisation capacity (ANC) in stream runoff using data sets from two regional surveys of a major area of acidificat...

The arid zone catchments of the Lake Eyre Basin (LEB, area of 1.2*10km) in central Australia have unregulated, highly variable flow regimes and contain a paucity of gauging stations. In developing hydrological models of these catchments, only limited gauging station data are available for identifying the broad landscape differences influencing runoff and streamflow. The catchments have been div...

Areas of the Last Glaciation in northern Poland differ widely as to the conditions controlling the formation of river runoff and solute loads. The aim of the research was to identify chief mechanisms of stream alimentation in this area depending on the scale of a catchment. The analysis rested on data from hydrochemical profiling. Three types of systems were found to occur: in spring-head catch...

Soil loss expectation and possible relationships among soil erosion, riparian vegetation and water quality were studied in the São José dos Dourados River basin, State of São Paulo, Brazil. Through Geographic Information System (GIS) resources and technology, Soil Loss Expectation (SLE) data obtained using the Universal Soil Loss Equation (USLE) model were analyzed. For the whole catchment area...

We evaluated the impacts of natural wetlands and various land uses on stream nitrogen concentration in two grassland-dominated catchments in eastern Hokkaido, Japan. Analyzing land use types in drainage basins, measuring denitrification potential of its soil, and water sampling in all seasons of 2003 were performed. Results showed a highly significant positive correlation between the concentrat...

The purpose of this paper is to review the current research on catchment areas of private general practices in different developed countries because healthcare reform, including primary health care, has featured prominently as an important political issue in a number of developed countries. The debates around health reform have had a significant health geographic focus. Conceptually, GP catchme...