Soil system based productivity management of fish ponds in red andlateritic soil zones

摘要

The importance of bottom soils in influencing productivity of fish ponds is well known. These soils not only aid in the gradual release of different nutrient elements to available forms for the benefit of the primary fish food organisms and, in turn, the growth of fishes, they also control many of the significant bio-chemical reactions occurring in aquatic ecosystems. Hickling (1971) recognized the importance of pond soils to fish culture calling soils the "Chemical Laboratory" of fish ponds. However, in spite of their importance, little attention is paid to the nature and properties of bottom soils when undertaking pond fish culture operations in different locations with varying soils. Basic properties of a particular soil group are different from others. The fish ponds situated in one soil zone are likely to exhibit some specific properties of the soil and water environment that are reflected in their biological productivity levels. Thus, widespread use of one standard pond fertilization recommendation will be of limited value. Any effort to improve the soil and water quality of fish ponds located in a particular soil zone will, therefore, require adequate knowledge about the soil factors that may limit productivity with respect to that particular soil type. Based on this information only, the management practices for different fish ponds situated in different soil zones can be developed. In the present article, various aspects of nutrient management problems for fish ponds located in red and lateritic soil zones, a widely occurring soil group in the world, are discussed in relation to abatement of different productivity-limiting soil related problems.