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The coastal flanks of Mt Etinde is wedged between the sea and the southwestern slope of Mt Cameroon. The only fresh water resources available for multipurpose uses in this area are mountain springs and streams that drain volcanic materials. To access the sources, processes and assess the ecological risk associated with hydrochemicals and heavy metals in these mountain water resources, 18 water samples were collected in different seasons at 4 locations between may 2009 and december 2010 for major ions and heavy metals determination. The sampled waters ranged from neutral to slithly alkaline, weakly mineralized and dominated by Ca–Mg–HCO3 water type irrespective of season. The hydrochemical ratios revealed ions chemistry mostly influenced by geogenic source of silicate rock weathering and atmospheric inputs. Sampled waters had low concentration of heavy metals which are less mobile in the aqueous phase, controlled by hydraulic condition. Geochemical processes of mineral dissolution and reverse ion exchange coupled with hydrodynamic processes of flushing at the weathering front and soil leaching are the main controls on the water chemistry in the area. Despite agricultural and other anthropogenic activities, quality indices in the study area indicate the absence of anthropogenic inputs. Key words: Major ions, heavy metals, rocks weathering, soil leaching, water quality assessment.

Studies were conducted to assess the response of cowpea (Vigna unguiculata L. Walp) to some physical and chemical characteristics of soil in coastal region (Cameroon). The cowpea variety used in this trial was Tsacre, planted at a spacing of 80 cm × 80 cm. The experimental design was a randomized complete block comprising of five plots with three replicates. Productivity parameters (dry weight aerial parts, roots dry weight, abortion seeds rate, number of flowering per plant, flowering rate) and yield components (number of seeds per pod, number of pod per plant, grain yield, pod yield and weight of 1000 seeds) were determined. Soil samples were taken randomly from depths of 0 - 30 and 30 - 60 cm before seeds sowing. The results showed that the plot with the highest percentage of sand (71.80%), the lowest percentage of clay (21.00%) and silt (7.20%) and with the highest amount of organic matter (10.26%), exchange potassium (0.36 g Kg-1), calcium (0.49 g Kg-1) and magnesium (0.46 g Kg-1) increased significantly (P