Riparian vegetations are important in supporting ecological connectivity between aquatic and terrestrial ecosystems. The structure and species composition of riparian woody plants have been subjected to multiple force...Riparian vegetations are important in supporting ecological connectivity between aquatic and terrestrial ecosystems. The structure and species composition of riparian woody plants have been subjected to multiple forces with varying degree of influences. This study examined the influence of land use and environmental gradient to the structure and composition of the riparian woody plants in northern Tanzania. A total of 270 plots were surveyed for woody plant species in the riparian ecosystems and later analysed to determine the influence of land use categories (homegarden, crop field, woodlot, open canopy forest, and closed canopy forest) and environmental variables (temperature, precipitation, elevation and slope) to the species richness, abundance, and stand parameters. Basal area was higher in woodlots, homegardens and crop fields than in the open and closed canopy forests;and as expected the reverse was true for the number of stocking density. Correlation among stand parameters with environmental variables varied significantly. Species richness and species abundance were negatively correlated to precipitation, temperature and elevation, while stocking density and basal area were positively correlated to precipitation. The study recommends continual retentions of trees on farm, further promoting of agroforestry interventions and sustainable utilization of woody plants in open and close canopy forests.展开更多
Despite all of the many discrepancies and contradictions in the estimate of the water balance in the Barada Awaj basin, all the research and reports, both local and international, indicate that the basin suffers from ...Despite all of the many discrepancies and contradictions in the estimate of the water balance in the Barada Awaj basin, all the research and reports, both local and international, indicate that the basin suffers from water depletion. The agricultural sector is the largest consumer of water, and the area of land irrigated by the basin has risen significantly. Rapid population growth as a result of natural increase and massive immigration to the basin, piratical well-digging without permits, the failure to increase the area of land irrigated by modern methods and a decrease in rainfall and the drought that has affected Syria in general and the Barada Awaj basin in particular, have led to a water shortage in the basin during the first decade of this century.展开更多
Freshwater scarcity is a global issue of environmental concern that threatens agricultural production and human health.In this study,we established freshwater stress indices(WSIs) for the nine water basins of Tanzania...Freshwater scarcity is a global issue of environmental concern that threatens agricultural production and human health.In this study,we established freshwater stress indices(WSIs) for the nine water basins of Tanzania by using the quantity of freshwater available and various water uses.The relationship between water availability and different water uses,including environmental water requirements,was analyzed,with uncertainty and sensitivity analysis performed by a Monte Carlo simulation technique.Extreme WSI values close to 1.00 were obtained in the Rufiji,Pangani,and Wami-ruvu basins,Internal drainage,and Lake Rukwa,while low and moderate WSI values ranging from 0.03 to 0.84 were found in Lake Victoria and the Ruvuma,Tanganyika,and Nyasa basins.This study adds further knowledge on the level of freshwater scarcity,relationships between water availability and different water uses,and suggests policy options to reduce freshwater scarcity at the basin level for sustainable water supply.展开更多
The article presents the results of research conducted in Dengizkul and around this area. It identifies plant species in and around the lake and analyzes species composition. As a result of the analysis, 70 species of...The article presents the results of research conducted in Dengizkul and around this area. It identifies plant species in and around the lake and analyzes species composition. As a result of the analysis, 70 species of tall plants belonging to 24 families were identified in the lake. The identified species are divided into aquatic and riparian plants. Of these, 18 species are found in lake water and 52 species in its vicinity. The low number of high plant species in the lake water is due to the salinity of the water. The protection of this area is based on the natural conservation of the surrounding plant <span style="font-family:Verdana;">population.</span>展开更多
Research of water resources restoration of natural Dnieper river and man-made nature was carried out. The studies of water quality at working and peak operating modes of production cooling equipment were carried out. ...Research of water resources restoration of natural Dnieper river and man-made nature was carried out. The studies of water quality at working and peak operating modes of production cooling equipment were carried out. The conditions for the supersaturation of poorly soluble salts of the basin ( = 72.34;= 12.54) and accumulation of sediments of the reservoir are determined. The gravity tools for the restoration of water resources are proposed. A criterion equation for recharge the circulating system at peak mode was obtained. The granulometric potential of waste sediments at environmental feasibility is analyzed. The research involved supercritical temperature modes, taking into account precipitation hyperthermia. In the process of conducting a hydrological study, an evolutionary equation sediment model has been developed. The calculations of the technological flow capacity limits by of 125 W/m2 due to turbidity (750 mg/l) and hardness (up to 12 mg ekv per liter) of water resources are obtained. Mechanical sedimentation of the water stream increasing the energy potential up to 275 W/m2 was determined. The use of chemical agents (ozone) as a combined treatment increasing the flow potential up to 650 W/m2 is achieved. The application of technical way to natural water improving power to 975 W/m2 is received. Erosion of the bottom of the basin reduces the hydrological potential due to the unfinished state of biodegradation of sediments. The hydrological characteristics of the stream at a distance of 3000 m with characteristic technogenic inclusions were obtained. The study was conducted at natural Dnieper river and laboratory conditions with chemical catalyst and mechanical activator.展开更多
文摘Riparian vegetations are important in supporting ecological connectivity between aquatic and terrestrial ecosystems. The structure and species composition of riparian woody plants have been subjected to multiple forces with varying degree of influences. This study examined the influence of land use and environmental gradient to the structure and composition of the riparian woody plants in northern Tanzania. A total of 270 plots were surveyed for woody plant species in the riparian ecosystems and later analysed to determine the influence of land use categories (homegarden, crop field, woodlot, open canopy forest, and closed canopy forest) and environmental variables (temperature, precipitation, elevation and slope) to the species richness, abundance, and stand parameters. Basal area was higher in woodlots, homegardens and crop fields than in the open and closed canopy forests;and as expected the reverse was true for the number of stocking density. Correlation among stand parameters with environmental variables varied significantly. Species richness and species abundance were negatively correlated to precipitation, temperature and elevation, while stocking density and basal area were positively correlated to precipitation. The study recommends continual retentions of trees on farm, further promoting of agroforestry interventions and sustainable utilization of woody plants in open and close canopy forests.
文摘Despite all of the many discrepancies and contradictions in the estimate of the water balance in the Barada Awaj basin, all the research and reports, both local and international, indicate that the basin suffers from water depletion. The agricultural sector is the largest consumer of water, and the area of land irrigated by the basin has risen significantly. Rapid population growth as a result of natural increase and massive immigration to the basin, piratical well-digging without permits, the failure to increase the area of land irrigated by modern methods and a decrease in rainfall and the drought that has affected Syria in general and the Barada Awaj basin in particular, have led to a water shortage in the basin during the first decade of this century.
基金supported by the Key Laboratory of Industrial Ecology and Environmental Engineering,China Ministry of Educationthe Faculty of Science and Technology,Mzumbe University,Tanzania
文摘Freshwater scarcity is a global issue of environmental concern that threatens agricultural production and human health.In this study,we established freshwater stress indices(WSIs) for the nine water basins of Tanzania by using the quantity of freshwater available and various water uses.The relationship between water availability and different water uses,including environmental water requirements,was analyzed,with uncertainty and sensitivity analysis performed by a Monte Carlo simulation technique.Extreme WSI values close to 1.00 were obtained in the Rufiji,Pangani,and Wami-ruvu basins,Internal drainage,and Lake Rukwa,while low and moderate WSI values ranging from 0.03 to 0.84 were found in Lake Victoria and the Ruvuma,Tanganyika,and Nyasa basins.This study adds further knowledge on the level of freshwater scarcity,relationships between water availability and different water uses,and suggests policy options to reduce freshwater scarcity at the basin level for sustainable water supply.
文摘The article presents the results of research conducted in Dengizkul and around this area. It identifies plant species in and around the lake and analyzes species composition. As a result of the analysis, 70 species of tall plants belonging to 24 families were identified in the lake. The identified species are divided into aquatic and riparian plants. Of these, 18 species are found in lake water and 52 species in its vicinity. The low number of high plant species in the lake water is due to the salinity of the water. The protection of this area is based on the natural conservation of the surrounding plant <span style="font-family:Verdana;">population.</span>
文摘Research of water resources restoration of natural Dnieper river and man-made nature was carried out. The studies of water quality at working and peak operating modes of production cooling equipment were carried out. The conditions for the supersaturation of poorly soluble salts of the basin ( = 72.34;= 12.54) and accumulation of sediments of the reservoir are determined. The gravity tools for the restoration of water resources are proposed. A criterion equation for recharge the circulating system at peak mode was obtained. The granulometric potential of waste sediments at environmental feasibility is analyzed. The research involved supercritical temperature modes, taking into account precipitation hyperthermia. In the process of conducting a hydrological study, an evolutionary equation sediment model has been developed. The calculations of the technological flow capacity limits by of 125 W/m2 due to turbidity (750 mg/l) and hardness (up to 12 mg ekv per liter) of water resources are obtained. Mechanical sedimentation of the water stream increasing the energy potential up to 275 W/m2 was determined. The use of chemical agents (ozone) as a combined treatment increasing the flow potential up to 650 W/m2 is achieved. The application of technical way to natural water improving power to 975 W/m2 is received. Erosion of the bottom of the basin reduces the hydrological potential due to the unfinished state of biodegradation of sediments. The hydrological characteristics of the stream at a distance of 3000 m with characteristic technogenic inclusions were obtained. The study was conducted at natural Dnieper river and laboratory conditions with chemical catalyst and mechanical activator.
