ABSTRACT: There is need to determine the exact nature of river systems for key decisions such as water treatment, construction of irrigation dams, piping systems or bridges to be made. Seasonality affects the nature and amounts of compounds getting into or out of rivers. It is therefore critical to know the exact amounts of physico-chemicals and ligands in water systems. This study aimed at analyzing the levels of various physico-chemicals and ligands in the rivers of Sigor division, West Pokot county, Kenya during different seasons. Sampling was done at four different parts of the four rivers (Weiwei, Chesogon, Lomut and Muruny) during both the wet and dry seasons. Analysis was then conducted, in situ for most physico-chemicals and later on by UV-VIS spectroscopy for the ligands. The findings revealed that there was a great impact of seasonality on most of the physico-chemical parameters analyzed. Crucial parameters such as pH, temperature, conductivity and turbidity were all affected by seasonality. The rivers did not however differ significantly in most of the physico-chemical parameters. Muruny river, however experienced more values of physico-chemical parameters due to its agricultural neighborhood. The phosphate values in the rivers were way above the permissible values. However, nitrate values were within the recommended values whereas sulfate values in the rivers were below the threshold values.

ABSTRACT: The aim of this study was to investigate the effects of different tillage practices on bulk density, and the hydraulic properties of a sandy loam soil of eastern Tunisia. A replicated randomized complete block design with treatments consisting of (i) no-tillage (NT), (ii) tillage with moldboard plow at three level depths (SM=15cm, MM=20cm and DM=25cm), (iii) and tillage with disc plow at three level depths (SD=15cm, MD=20cm and DD=25cm) practices established at the Higher Institute of Agricultural Sciences of Sousse; Tunisia was used for the study. The soil bulk density and saturated hydraulic conductivity were determined for each of the treatments. The bulk density (BD) was determined at the depths of 5, 15 and 25 cm while the saturated hydraulic conductivity was determined on the surface (0-10 cm) soil. Experimental results showed that all the tillage practices were significantly different in their effects on soil density and was in the descending order of NT>SD> MD>DD>SM>MM>DM. The soil bulk density decreased with the degree of soil manipulation during tillage practices, with NT having the highest (1.76; 1.86 and 1.81g cm^-3) and DD having the least (1.60; 1.56 and 1.59g cm^-3) respectively for 5, 15 and 25cm depths. The greater mean value of Ksat was found in DD while the lowest was found in NT with 36% reduction than DD. The research concluded that the best Tillage Practices to be adopted in terms of improvement in physical and hydraulic properties is Shallow tillage practice.