ABSTRACT

The status of the environmental resources and management of Urudu watershed was studied at the forested and agroforestry ecosystems at Okoko Item, Nigeria. Humans' activities and the need for baseline data within specific ecosystems necessitated this study. A 150m (width) by 1250m (length) area covering both banks of the Urudu stream, and forested and agroforestry sites was mapped out for study. A stratified random sampling technique was used to administer 200 questionnaires to elicit information on the status of the watershed in terms of available resources, resource management and impact of human activities on the resources and the watershed. A single factor experiment in randomized complete block design (RCBD) with 5 rephcations was used to study the abundance and diversity of woody plant species above 5mc diameter-at-breast (D. B. H.); non-woody plant species were also identified and counted. The watershed stream water quality over time (January, March and June 2003 and 2004) was studied using a 2x3 factorial experiment in RCBD with three replications. The physical and chemical properties of the watershed soils at the forested and agroforestry sites were studied using a 4x2 factorial experiment in RCBD during the rainy and dry seasons in 2003 and 2004. Species abundance and diversity were measured within sites using Menhinick's (1964) and Simpson's (1949) diversity indices respectively. Water quality and soil physico-chemical properties of the watershed were also analysed. Results indicate that in the forested site, 1071 individual woody plants ha1 comprising 69 species and 29 families were encountered with species abundance index of 2.11 and diversity index of 0.82. Also, 450 individual nonwoody plants ha distributed within 36 species and 24 families with species abundance index of 1.70 and diversity index of 0.86 were obtained. The agroforestry site had 999 individual woody plants ha 1 consisting of 80 species and 31 famifies with species abundance index of 0.88 and diversity index of 0.84. The site had 1586 non-woody individual plants ha 1 consisting of 27 species and 21 families with an forested and agroforestry sites included some economic plants, food species, leafy vegetable species, and spices. The results of the water quality indicate that the Urudu stream water quality compares favourably with established standards for drinking water quality and other uses. The watershed soil is heterogeneous in terms of texture, physical and chemical characteristics. The soil is high in Nitrogen (0.24 mg p1), Phosphorus (34.08 mg r1), Magnesium (2.10 mg r1) and Organic matter (5.18%) based on soil fertility assessment standards of National Special Programme for food Security, Nigeria. Diverse human activities take place within the Urudu stream watershed. The watershed is directly managed by the community. In conclusion, environmental resources, if sustainably managed, is an asset base that can be drawn upon, built upon, traded and developed. This study recommends inter alia that periodic stock survey of natural resources of watersheds be taken. This will enhance management of the watershed for sustainable exploitation, environmental resources conservation, agriculture for optimal food production, and provision of current data on Nigeria's extremely diverse environmental resources.