نتایج جستجو برای: freshwater
تعداد نتایج: 28555 فیلتر نتایج به سال:
fish diversity in freshwater perennial water bodies in east midnapore district of west bengal, india
present survey synthesized information on fish biodiversity in the perennial freshwater body of ramnagar, east midnapore district of west bengal, india. we documented 45 fish species under 29 genera, 18 families and 8 orders during the periods from1990 to 1995, whereas, 34 species from 21 genera and 12 families under 7 orders were recorded presently from freshwater body of different perennial p...
shortage of irrigation water, being a crucial problem in arid and semiarid regions, makes it necessary to use treated wastewater in agriculture. a field experiment was conducted to investigate the effect of treated municipal wastewater (tmw) on the yield and fiber quality of cotton (gossypium hirsutum l.) (mehr variety). treated municipal wastewater was supplied from shahrake ghods sewage treat...
this research was conducted to study the length-weight and length-length relationships and condition factor of six cyprinid fish species viz. alburnus atropatena , barbus lacerta , capoeta capoeta , carrasius gibelio , romanogobio macropterus and pseudorasbora parva from zarrineh river (urmia lake basin, iran). a total of 188 specimens ranging from 2.9 to 21.4cm in total length and 0.22 to 176g...
Freshwater biodiversity is highly threatened and is decreasing more rapidly than its terrestrial or marine counterparts; however, freshwaters receive less attention and conservation investment than other ecosystems do. The diverse group of freshwater megafauna, including iconic species such as sturgeons, river dolphins, and turtles, could, if promoted, provide a valuable tool to raise awareness...
Freshwater habitats occupy ,1% of the Earth’s surface, yet are hotspots that support ,10% of all known species, and ,M of vertebrate species. Fresh waters also are hotspots for human activities that have led to widespread habitat degradation, pollution, flow regulation and water extraction, fisheries overexploitation, and alien species introductions. These impacts have caused severe declines in...
Azorean freshwater invertebrates: Status, threats and biogeographic notes This paper presents an updated catalogue of the freshwater invertebrates of the Azores archipelago and reviews the published records to account for the current taxonomic status and changes in the nomenclature of the listed taxa. The number of freshwater invertebrate species that has been recorded in the Azores has risen s...
Combined effects of cumulative nutrient inputs and biogeochemical processes that occur in freshwater under anthropogenic eutrophication could lead to myriad shifts in nitrogen (N):phosphorus (P) stoichiometry in global freshwater ecosystems, but this is not yet well-assessed. Here we evaluated the characteristics of N and P stoichiometries in bodies of freshwater and their herbaceous macrophyte...
Giorgos Chatzigeorgiou*, Elena Sarropoulou, Katerina Vasileiadou, Christina Brown, Sarah Faulwetter, Giorgos Kotoulas and Christos D. Arvanitidis 1 Biology Department, University of Crete, Heraklion, Greece 2 Hellenic Centre for Marine Research, Institute of Marine Biology, Biotechnology and Aquaculture, Heraklion, Greece 3 Department of Biology, Chemistry and Pharmacology, Institute of Biology...
The authors investigate the response of the Arctic Ocean freshwater budget to changes in the North Atlantic Oscillation (NAO) using a regional-ocean configuration of the Massachusetts Institute of Technology GCM (MITgcm) and carry out several different 10-yr and 30-yr integrations. At /68 (;18 km) resolution the model resolves the major Arctic transport pathways, including Bering Strait and the...
Human activities have severely affected the condition of freshwater ecosystems worldwide. Physical alteration, habitat loss, water withdrawal, pollution, overexploitation and the introduction of non-native species all contribute to the decline in freshwater species. Today, freshwater species are, in general, at higher risk of extinction than those in forests, grasslands and coastal ecosystems. ...
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