Environmental and socioeconomic constraints to the development of freshwater fish aquaculture in China

In this article, we provide an overview on freshwater fish aquaculture in P .R. China, with special emphasis on pond fish culture. We describe the hist ory, ecology (trophic structure and species reared), and technological aspe cts (including inputs/outputs, yields, labor productivity, and fossil energ y use) of freshwater fish production and analyze its role in relation to th e socioeconomic context. We discuss the prospects for intensification of pr oduction. In China, freshwater fish aquaculture has always been closely linked to cul tivation of crops and animal husbandry, that is, feed inputs are in the for m of agricultural wastes. The close integration with the farming system at large results in an efficient use of nutrients, low environmental loading, and little dependence on fossil energy inputs. About 7 to 9 different fish species, mainly herbivores, are kept in the same pond and efforts are made to maintain as much as possible the natural mechanisms of matter regulation and energy flows within the pond ecosystem. However, ecological compatibil ity is paid for by relatively low productivity, both per hectare of waterbo dy and per hour of labor input. If the throughput of freshwater fish produc tion per unit of area and labor are to be dramatically increased, the equil ibrium of the traditional integrated system will be difficult to maintain.