نتایج جستجو برای: macroinvertebrate
تعداد نتایج: 1654 فیلتر نتایج به سال:
Scientists have long assumed that the physical structure and condition of stream and river channels have pervasive effects on biological communities and processes, but specific tests are few. To investigate the influence of the stream-reach geomorphic state on in-stream habitat and aquatic macroinvertebrate communities, we compared measures of habitat conditions and macroinvertebrate community ...
Invasive species are a major cause of species extinction in freshwater ecosystems, and crayfish species are particularly pervasive. The invasive American signal crayfish Pacifastacus leniusculus has impacts over a range of trophic levels, but particularly on benthic aquatic macroinvertebrates. Our study examined the effect on the macroinvertebrate community of removal trapping of signal crayfis...
1. The structure of lotic macroinvertebrate communities may be strongly influenced by land-use practices within catchments. However, the relative magnitude of influence on the benthos may depend upon the spatial arrangement of different land uses in the catchment. 2. We examined the influence of land-cover patterns on in-stream physico-chemical features and macroinvertebrate assemblages in nine...
Many studies have tried to elucidate the main factors influencing macroinvertebrate community composition and abundance in streams (e.g. Hart 1992, Dudgeon 1994, Giller & Twomey 1993, Maridet et al. 1998, Tierney et al. 1998, Pardo 2000, Doisy & Rabeni 2001). Considerable attention has been paid to food resources (e.g. Hawkins & Sedell 1981, Cowan & Oswood 1984, Boulton & Lake 1992, Friberg 199...
The study of benthic macroinvertebrate communities is one of the most common methods for assessing the effects of stresses on the biological conditions of aquatic ecosystems and water quality monitoring. This research was conducted to study the changes in the macroinvertebrate communities in the Shanbeh-Bazar River, Anzali International wetland and the effects of environmental factors. Sampling...
the distribution of macroinvertebrate communities from 5 sampling sites of the tajan river were used to examine the relationship among physiochemical parameters with macroinvertebrate communities and also to assess ecological classification system as a tool for the management and conservation purposes. the amount of variation explained in macroinvertebrate taxa composition is within values repo...
Impacts of effluent from fish farming activities on fluvial ecosystems lead to deterioration of water quality and changes in the macroinvertebrates assemblage. In this study, the influence of fish farm effluents on water quality and macroinvertebrates communities of Tajan River was investigated to evaluate the suitability of macroinvertebrates based on biological metrics and indices. Benthic...
Laboratory tests of fipronil and its degradation products have revealed acute lethal toxicity at very low concentrations (LC50) of <0.5 microg/L to selected aquatic macroinvertebrates. In streams draining basins with intensive rice cultivation in southwestern Louisiana, USA, concentrations of fipronil compounds were an order of magnitude larger than the LC50. The abundance (rho=-0.64; p=0.015) ...
Among all the malaria controlling measures, biological control of mosquito larvae may be the cheapest and easiest to implement. This study investigated baseline predation of immature mosquitoes by macroinvertebrate predators along the Mara River, determined the diversity of predators and mosquito larvae habitats and the range of their adaptive capacity to water physico-chemical parameters. Betw...
Title of Dissertation: MACROINVERTEBRATE COMMUNITY STRUCTURE AND ECOLOGICAL FUNCTION IN MARYLAND COASTAL PLAIN STREAMS Degree Candidate: Nicholas A. Baer Degree and Year: Doctor of Philosophy, 2004 Thesis directed by: Professor William O. Lamp Department of Entomology Abiotic conditions within streams, especially those conditions impacted by human activities, often influence the community struc...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید