نتایج جستجو برای: wetland environmental quality
تعداد نتایج: 1098932 فیلتر نتایج به سال:
/ This paper presents a foundation for improving the risk assessmentprocess for freshwater wetlands. Integrating wetland science, i.e., use of anecosystem-based approach, is the key concept. Each biotic and abiotic wetlandcomponent should be identified and its contribution to ecosystem functionsand societal values determined when deciding whether a stressor poses anunreasonable risk to the sust...
We measured organic carbon input and content of soil in two wetland areas of Chongming Dongtan (Yangtze River Estuary) to evaluate variability in organic carbon accumulation capability in different wetland soils. Observed differences were investigated based on the microbial activity and environmental factors of the soil at the two sites. Results showed that the organic carbon content of wetland...
gol-e-gohar iron ore mine of sirjan in southern part of iran is a large open pit that operates below the groundwater table and during mining operation, dewatering is required to prevent operation processes from flooding. current operation is going on by digging wells in or out of the pit and pumping to prevent flooding. as a result of the former dewatering operation a vast deep cone of depressi...
The impact of soil filtered runoff from a section of the M25 outer London motorway (constructed in 1981) on a pond, wetland and stream in a nature reserve was investigated by monitoring water, sediment. The tissues of the emergent plants Typha latifolia and Glyceria maxima collected from the pond were analysed for the heavy metals, Cd, Pb, Cu and Zn. Macroinvertebrates were monitored in the str...
Surface water and groundwater are continuously used as sources of drinking water in many metropolitan areas of the United States. The quality of water from these sources may be reduced due to increases in contaminants such as Escherichia coli from urban and agricultural runoffs. In this study, a multiplex fluorogenic PCR assay was used to quantify E. coli O157:H7 in soil, manure, cow and calf f...
A method developed to evaluate the cumulative effect of wetland mosaics on water quality was applied to 33 lake watersheds in the seven-county region surrounding Minneapolis-St. Paul, Minnesota. A geographic information system (GIS) was used to record and measure landscape variables derived from aerial photos. Twenty-seven watershed land-use and land-cover variables were reduced to eight princi...
Urs Uehlinger Department of Aquatic Ecology, Swiss Federal Institute of Aquatic Science and Technology (Eawag), CH-8600 D€ ubendorf, Switzerland Karl M. Wantzen Limnological Institute, University of Konstanz, ATIG-Aquatic-Terrestrial Interaction Group, D-78457 Konstanz, Germany Rob S.E.W. Leuven Department of Environmental Science, Institute for Water and Wetland Research (IWWR), Faculty of Sci...
Nutritional, behavioral, and diet data for lesser scaup (Aythya affinis [Eyton, 1838]) indicates that there has been a decrease in amphipod (Gammarus lacustris [G. O. Sars, 1863] and Hyalella azteca [Saussure, 1858]) density and wetland quality throughout the upper-Midwest, USA. Accordingly, we estimated densities of Gammarus and Hyalella in six eco-physiographic regions of Iowa, Minnesota, and...
Although the components of plan quality are well defined, little empirical research has been conducted to understand the degree to which policies are being implemented after plan adoption and the factors contributing to the variation in plan implementation. The authors test the efficacy of land-use planning and plan implementation in Florida by measuring the degree to which wetland development ...
To test whether large amounts of phosphorus (P) are accumulated in the floodplain during dry antecedent conditions, and whether they would be released as the predominant source of P in the overlaying floodwater, in accord with the Flood Pulse Concept, we calculated the mass balance of P in an intermittent floodplain wetland after environmental water application. The P mass balance was calculate...
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