ALLEVIATING SOIL COMPACTION BY ORGANIC AMENDMENTS ON CROPPING FIELDS IN A PART OF NIGERIA’S SAVANNA REGION

It is well recognized 'that organic amendments in cropping field, especially on long term, alleviate soil compaction. The extent of such however varies clearly with soil condition, bio-climatic conditions of an area, levels of the amendments themselves, cropping history and land management techniques each of which can vary from an area to another. In this article, a brief report is given of a study conducted to examine the combative effects of long term (1961-1991) organic manure amendments on two key indices of soil compaction (bulk density and total porosity) in Konduga area of Nigeria's Suduno-Sahelian region. This was done by examining soils of 15 farmer-managed plots, and those of uncultivated plots under long-standing, semi-natural vegetation cover. The results obtained reveal that even though the cultivated plots vary in age, of between 5-30 years, as at the time of soil sampling (1991), there are very low spatial variations in mean values of the two soil structural properties of the 15 plots. The properties of the cultivated plots have been maintained at about 100% of the values of the same properties of the uncultivated plots. These results thus suggest that on both short and long term bases, the use of organic manure in soil fertility-maintenance-in the study area can possibly reverse the degradation trends occasioned by soil compaction.