ABSTRACT
The primary purpose of manuring ponds is to create conditions which facilitate an increase in the stocks of good quality natural foods, thereby increasing fish production. An increase in fish production is associated with density of stocking. The effectiveness of manuring depends on many factors: water temperature, pH, oxygen regime, soil of the pond, and technical state of the pond. Chemical fertilizers applied to pond soil are initially absorbed by the soil and then gradually released. Different combinations of fertilizers are practiced in pond fisheries: phosphorus and potassium, phosphorus and calcium, phosphorus with potash and calcium, nitrogen and potassium, and nitrogen with phosphorus and potassium. Recommendations for the inclusion of trace elements in fish pond melioration can only be made after undertaking an intensified and integrated study of their influence on the medium and its inhabitants, especially fish reared for human consumption. Organic manures used in pond fisheries include dung, liquid compost, compost, and green manure.
