Abstract： This study uses Climate Model outputs of HadCM3A2a and HadCM3B2a SRES climate scenarios and downscale the predictors into finer scale resolution using Statistical Downscaling Model (SDSM) to simulate and project the climate at local scale in order to investigate the hydrological impact of possible future climate change in Guder catchment, Upper Blue Nile Basin (Ethiopia). The results, obtained from this climate model, were compared to the observational datasets for precipitation and temperature for the period 1990-2008. To estimate the level of impact of climate change, climate change scenarios of precipitation and temperature were divided into time windows of 30 years each from 2011 to 2100.The downscaled A2a and B2a emission scenarios result indicates a significant increasing trend in mean temperature and precipitation in all future time periods in the study catchment. We applied the Soil and Water Assessment Tool (SWAT) to investigate the response of the water resources of the Guder River catchment to the scenarios of projected climate change. The model output shows that there may be an annual and seasonal increase in inflow volume for both A2a and B2a emission scenarios in three benchmark periods in the future. Potential evapotranspiration in the catchment will also increase up to 25％. Generally, results presented in this study can provide valuable insight to decision makers on the degree of vulnerability of Guder river catchment to climate change, which is important to design appropriate adaptation and mitigation strategies.

Abstract： The physico-chemical and bacteriological quality of water and sediments and the growth performance of fish following administration of Oreochromis niloticus feeds of two different dietary protein levels were studied in Hapas set in four 200 m2 ponds. Results indicate that water quality parameters monitored were within environmental tolerable limits and for the growth of Oreochromis niloticus. For all the feeds, water temperature was in the range of 27.83°C - 28.67°C, dissolved oxygen 5.01mg/L - 6.11 mg/L and pH 5.4 - 7.01. The levels of biochemical oxygen demand, nitrogen, phosphorus and dissolved organic carbon as well as Salmonella sp, Staphylococcus aureus and Pseudomonas sp were generally beyond acceptable limits with projections of the levels of the physico-chemical parameters indicating further increase. There were no statistical significant differences (P>0.05) in the levels of total nitrogen, phosphorus, biological oxygen demand, dissolved organic carbon and bacteria load before the administration of treatments and at the end of the study.

Abstract： Networks are an opportunity for more efficient and more effective disposal of water resources. The use of the net in the management of water systems, river and sea-river channels, emphasize the efficiency of integrated water resources decisioning. The conclusions of geomorphogical and paleohydrologic research can provide a more complete picture of hydrological potentials, and adequate hydrological management. The paper recognizes permeations as the basis for designing river channel systems, planning and implementation of rivers, lake-river and sea-river channels in order to better exploit water resources and connect river flows. In this there are prerequisites for water management of the construction of systemic river traffic distances of completely regulated or at least controllable river systems. The analysis of large continental rivers is made by the observation of water systems, comparisons and useful conclusions of the European, African and Asian network systems, as well as the possibilities of their further use and development.

Abstract： In the face of a growing demand for portable water catalyzed by population and rapid urbanization, there exist a precarious imbalance between water availability and accessibility by the populace. This study seeks to assess residential water demand and distribution as it relates to urban population change in Jalingo, Taraba State Mapping of the existing water supply network was achieved through Geo-referencing and digitization of scanned map obtained from Jalingo Water Agency; Landsat image of 1986, 2001 and 2016 were used for land use land cover classification and change detection analysis adopted to provide insight into spatio-temporal variation in urban extent; population data obtained from National Population Commission was used to analyze population trend and density analysis; using simple regression analysis, the relationship between urban population change and water demand was established; and weighted overlay analysis (WOA) which incorporated elevation and the various land use and cover classes was adopted to identify suitable areas for siting proposed buffer stations and new service areas for water supply facilities within the study area. The results reveal that the population of Jalingo stands 159,950 with a growth rate of 3.2％ coupled with spatial variation in density ranging from 10-80 people per km2 both in the core and peripheral areas. Using built-up area as an indicator of urban change, the associated urban expansion rate from 1986 to 2016 stands at 23％. The increase in population also correlated strongly with water demand (p-value<0.05) and indicates that water demand may outweigh supply at the current coverage of water distribution facilities. Furthermore, demand was projected to be about 7.9 billion cubic meters by 2031. These therefore creates the need for optimization which proposed more buffer stations and facility expansion with a view to enhancing sustainable planning and management of residential water consumption and distribution in the study area.