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Background: The study area exhibits a first class catena; variation in soils is a result of differences in drainage and lateral movement of materials. The site was delineated into Soil Mapping Units (SMUs) through augering, into soils differing in macro relief. Slope categories included 0 to 5%, 5 to 8%, 8 to 16%, 16 to 30% and > 30%. Profile pits were opened in the five mapping units using stratified random sampling technique. Identified SMUs include UmIr/F, UmIr/E, UxIr/D, UxIr/C and UxIr/AB in order of decreasing slope gradient. Land suitability classification was based on the top horizons and the FAO 1976 criterion for land evaluation was used. The study aimed at identifying the most suitable areas for envisaging production of common crops grown in the area and limitations to production increase. A table of relevant land qualities and their diagnostic factors was constructed, rated and matched with suitability classdefining criteria to determine current suitability. Potential suitability was determined by considering the possibility of resolving the current limitations. Results: Mapping unit UmIr/F and UmIr/E qualified as class S2 for the selected crops majorly due to limitations of workability and susceptibility to erosion based on their slope gradient. Nutrient availability and possibility of use of implements also rated as S2. Unit UxIr/D qualified in S2 category due to the same limitations. Mapping unit UxIr/C and UxIr/AB qualified in the S2 category due to limitations of nutrient availability. After improvements, all the mapping units qualified in class S1. Conclusions: These observations indicate that workability and erosion susceptibility due to steep topography coupled with lack of enough nutrients are the greatest production limitations in the study area. Increasing slope gradient also led to decreasing possibility of use of farm implements. Terracing can reduce the deleterious influence of slope on soil quality, shifting suitability to a higher class, should the steep area be used for cultivation. There is a need for sufficient inputs and cover cropping to maintain high soil quality. Land evaluation should be part of good agricultural practices in any production system.

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This study aimed to determine the levels of contamination in Maumau stream as a result of horticultural activities in its vicinity. The stream was purposefully delineated into three blocks including upstream, midstream and downstream, where water samples were collected and analyzed for physicochemical attributes. Standard analytical procedures for water analysis were followed in laboratory analysis and the collected data was analyzed using Genstat software. Analyzed parameters include total dissolved solids (TDS), salinity, total suspended solids (TSS), sulphates (SO 3 −3 ), phosphates (PO 3 −3 ), nitrates (NO 3 - ), fluoride (Fl − ), turbidity, chloride (Cl − ), magnesium (Mg +2 ), sodium (Na + ), potassium (K + ) and zinc (Zn +2 ). The results were presented in tables and a graph against WHO standards. All measured parameters showed significant differences (p=<0.001) among their means across the sampling sites and control. The pH did not show a clear trend from upstream through midstream to downstream. The concentrations of chloride decreased down the stream with control, midstream and downstream showing no statistical significance. Means of fluoride, magnesium, phosphates, sulphates, total soluble solids and zinc increased down the course of the stream. Increasing concentrations of the physicochemical parameters down the stream was attributed majorly to release and addition of agrochemicals to the stream from the nearby farms. A lucid knowledge of the nexus between land use and water quality was recommended as a prime management implication. In conclusion, the water quality of Maumau stream is being degraded by horticultural activities along the stream. Key policy actions including river pegging should be adopted to protect the water quality.