From a factorial experiment using a graded sand and three soils (sand, clay loam, and clay), five slopes (0.0, 3.5. 7.0, and 14.0 per cent) and four intensities (50. 80. 110, and 140 mm h-I), splash detachment and splash transport are described in terms of the direct effects and the first and second order interactions of these variables.The graded sand and three soils tested are significantly different in the mean weight of soil detached and transported. They can be placed in rank order of graded sand. sand, clay, and clay loam with increasing resistance to splash detachment. The amount of material transported is in the order of graded sand > clay > sand > clay loam. For each soil there are significant increases in splash detachment and splash transport with increasing rainfall intensity. Both splash parameters are significantly correlated with slope steepness.The most important interactions that influence splash detachment and splash transport are soil x intensity and slope x intensity respectively. Significant interactions show that the factors are not independent of each other; the simple effects of a factor differ, and the magnitude of any simple effect varies according to the level of the other factors of the interaction term. These interactions have not been explicitly studied in previous research on splash erosion.Power equations are established between splash activity and the above variables and reasonable working ranges for the exponents are suggested.

Soil erosion is a multifactor threat to crop production and the environment. Most studies on soil erosion characterization have not focused on soil nutrient loss associated with erosion. The aim of this study was therefore to quantify the magnitude of nutrient loss through soil erosion under different cropping systems and amendments to inform agronomic practices in sub-Saharan Africa (SSA). A field experiment was carried out on runoff plots with different cropping systems (sole maize, sole cowpea, sole maize and maize intercropped with soybean) as main plots and soil amendments (biochar, NPK (Nitrogen +Phosphorus +Potassium) fertilizer, NPK + biochar and a control (no amendment)) constituting the subplots in a randomized complete block design. For each block, a bare plot was included to assess the efficiency of the different crop and soil management practices on soil erosion. The study was carried out in three consecutive cropping seasons in the semi-deciduous forest zone of Ghana. The bare plots had the highest amounts of nitrogen (N), phosphorus (P), and potassium (K) eroded: 33.88, 12.35 and 12.75 kg ha-1 respectively followed by the control plots with magnitude of 20.43, 8.42 and 7.87 kg ha-1 respectively for N, P and K. Sole maize had the highest amounts of nutrient loss: 19.71, 8.12 and 7.27 for N, P and K respectively compared to all the other cropping systems where the losses varied respectively from 12.38 to 17.12, 6.67 to 7.49 and 5.81 to 6.75 kg ha-1 The legume-based cropping systems under inorganic fertilizer and biochar management effectively reduced nutrient loss more than all other treatment combinations. The off-site effect of soil erosion expressed as enrichment ratio (ER) was higher for all plots, which received inorganic fertilizer inputs varying from 1.93 to 3.06 while the other treatments had ERs of 1.51 to 2.03. The ERs of fine soil particles were greater than 1 (ranging from 1.14 to 3.6) being relatively higher than that of coarse particles (sand) with values below 1 (ranging from 0.62 to 0.88). The least cumulative monetary value of nutrient loss (30.82 US$ ha-1) was observed under cowpea cropping system which received NPK + BC treatment. Soil erosion affected directly soil nutrient depletion through nutrient loss; however, integrated soil fertility management associated with legume-based cropping systems can be alternative options to reducing its effects on croplands in SSA.

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Many small dams and dugouts have been constructed in the Upper East Region of Ghana to address the problem of regional water scarcity. The reservoirs were constructed primarily as water supplies for agricultural irrigation and livestock watering, aquaculture and domestic use. However, many of the reservoirs dry up during the dry season, affecting the livelihoods of their basin inhabitants. A major cause for the dried reservoirs is siltation, which reduces the reservoir's storage capacities. The goal of this study is to quantify the annual siltation rate of four study reservoirs, using a bathymetric survey and reservoir soil sampling. The sediment yield and its relation to catchment area also were assessed. The results of this study indicate that the annual siltation rates are 1272, 3518, 2764 and 6135 t year )1 for Doba, Dua, Zebilla and Kumpalgogo reservoirs, respectively. Analyses of the sediment yield and catchment areas illustrated that the sediment yields decreased with increasing catchment area. All the study reservoirs have lost their dead storage capacity, which was meant to store sediment until the end of their anticipated design lives. The decreasing storage capacity because of siltation will affect the livelihoods of the local basin inhabitants, as the reservoirs will not be able to achieve all their intended purposes. The results of this study indicate that, because siltation is not the only factor threatening the benefits gained from the reservoirs, the integrated assessment of all relevant factors is required.

The Millennium Development Goals call for a 50 per cent reduction in the proportion of people without sustainable access to safe drinking water and sanitation. Provision of these services by city authorities is often absent in slum(1) settlements in developing countries as these settlements are classified as illegal by city authorities. A field survey was conducted in two urban slums in the Asawase constituency of Kumasi, Ghana to ascertain the extent of "improved" water and sanitation coverage as defined by the WHO/UNICEF Joint Monitoring Programme. The study revealed adequate levels of improved water coverage, but both communities had extremely low coverage for improved sanitation (toilet) facilities within the households and most people depended on a very inadequate number of poorly maintained public toilets. Waste management practices in the two communities were also very poor. Findings from this study can be used by city authorities in planning effective sanitation intervention strategies for the communities.