ABSTRACT
Low-lying saline-alkali lands along the Yellow River in China suffer alternately between drought and waterlogging. Three models, including fish-grass, fish-livestock and fish-agriculture, were tested to search for ways to change existing patterns of ground water and salinity. The cost/benefit ratio was favourable for all three models of integrated fish farming. The highest production was associated with the highest quality of fish food while the lowest fish production was associated with manure fertilization of the water. This is because the salinity of pond water in these low-lying lands are higher than normal and the water is relatively barren of plankton and benthos. The objective in reclaiming alkali-saline lands is to raise the soil level and lower the water table, thus reducing the degree of evaporation from the soil surface which concentrates the salt. The shallower the ground water, the higher the rate of evaporation and the higher the alkali-saline content.
