نتایج جستجو برای: river basins
تعداد نتایج: 92307 فیلتر نتایج به سال:
Natural physical conditions and the politics of flood management provide the historical context for structural flood control that underlies modern flood hazards in the Sacramento Valley. The valley is a broad, low plain with backswamp basins that were frequently inundated prior to Anglo-American settlement, continuing until the modern flood-control system was established. Early attempts to emul...
The effects of climate change on hydrological regimes have become a priority area for water and catchment management strategies. The terrestrial hydrology driven by monsoon rainfall plays a crucial role in shaping the agriculture, surface and ground water scenario in India. Thus, it is imperative to assess the impact of the changing climatic scenario projected under various climate change scena...
A Water Footprint Assessment is carried out for Morocco, mapping the water footprint of different activities at river basin and monthly scale, distinguishing between surface- and groundwater. The paper aims to demonstrate the added value of detailed analysis of the human water footprint within a country and thorough assessment of the virtual water flows leaving and entering a country for formul...
The Pacific lamprey (Entosphenus tridentatus) is an anadromous fish once abundant throughout coastal basins of western North America that has suffered dramatic declines in the last century due primarily to human activities. Here, we describe the development of an environmental DNA (eDNA) assay to detect Pacific lamprey in the Columbia River basin. The eDNA assay successfully amplified tissue de...
BACKGROUND Extensive monitoring programs on chemical contamination are run in many European river basins. With respect to the implementation of the European Union (EU) Water Framework Directive (WFD), these programs are increasingly accompanied by monitoring the ecological status of the river basins. Assuming an impact of chemical contamination on the ecological status, the assignment of effect...
The current distribution of freshwater fishes across multiple basins along Eastern Brazil can be associated to two main events: river captures or temporary paleoconnections. Apparently, river captures had a more significant role on distribution and structuring of species from upland areas, such as Glandulocauda melanopleura. Populations of this species are found in contiguous drainages in prese...
The Northern Rivers Ecosystem Initiative (NREI) was established in the late 1990s to address important science questions resulting from previous studies undertaken by the Northern Rivers Basin Study (NRBS). This manuscript summarizes the results from a number of reports on hydrologic research conducted on the Peace-Athabasca-Slave river and lake systems. Specific concerns expressed by the NRBS ...
The chromosomes of one Cichlasoma facetum and three Geophagus brasiliensis populations from the headwaters of adjacent river basins (Paraná State, southern Brazil), were investigated using differential staining techniques (C-banding, Ag-NORs, DAPI and CMA3) and fluorescent in situ hybridization (FISH) with 18S rDNA and 5S rDNA probes. The diploid chromosome number (2n) was invariably 48 in the ...
Trichomycterus areolatus Valenciennes, 1846 is a small endemic catfish inhabiting the Andean river basins of Chile. In this study, the morphological variability of three T. areolatus populations, collected in two river basins from southern Chile, was assessed with multivariate analyses, including principal component analysis (PCA) and discriminant function analysis (DFA). It is hypothesized tha...
The Bouse Formation in the lower Colorado River trough holds an important record of the onset of the modern drainage patterns in the southwestern United States. It comprises calcareous and clastic infi ll deposited during fl ooding of several basins, including the Bristol and Blythe subbasins of Lake Bouse. An intercalated ash bed, which is key to constraining its depositional age, is exposed i...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید