BIOMASS, PROTEIN, FIBER AND LIGNIN PRODUCTION RESPONSES TO VARYING SOIL TEXTURE AND PRECIPITATION FOR A HUMID NIGERIAN SAVANNA

Herbaceous biomass, protein, fibre and lignin production responses to varying soil texture and precipitation was examined on soils with comp arable climate in Nigerian Guinea Savanna. The aim was to find out how the yield and chemical constituents of grasses and forbs growing on s oils of different soil particle size react to annual variation in rain fall. Samples were collected semi-systematically at peak standing biom ass from three 1-ha plots for three years, oven-dried at 80 degrees C, weighed and analyzed for crude protein, fibre and lignin. Grass yield decreased and forb yield increased with increase in rainfall in soils with high clay and silt contents and vice-versa in soils with high sa nd content. Crude protein and structural constituents (fibre and ligni n) of most of the plant species were higher in the year with lower rai nfall than in that with heavier rainfall. It is concluded that grasses and forbs respond differently to annual rainfall variation and their response is determined by soil texture.