Biodiversity and nutrition in rice-based aquatic ecosystems

The cultivation of most rice crops in irrigated, rainfed and deepwater systems offers a suitable environment for fish and other aquatic organisms. Indeed, it comes as no surprise for those who produce rice that a rich source of biological diversity is to be found in rice-based ecosystems. Wild and gathered foods, from the aquatic habitat, provide important diversity, nutrition and food security as food resources from ricefield environments supply essential nutrients that are not adequately found in the diet. Development plans that focus only on increasing yields of rice may possibly give people more rice to eat, but at the same time may take away many of the aquatic animals and plants harvested from and around the rice fields. Many of the aquatic organisms found in rice ecosystems also play an important role as biological control agents of vectors and pests. Moreover, farmers have experienced that the concurrent culture of fish with rice often increases rice yields. This is reflected in an increase of the net income which is reportedly 7-65% higher on rice-fish farm as compared to rice monoculture farms. Rice fields may also harbour species which are under threat of extinction. The understanding for the value of aquatic biodiversity from rice-based ecosystems for food and nutrition needs to be well integrated into national agricultural systems that embrace the concepts of an ecosystem approach and the important role of agrobiodiversity for people and the environment. (c) 2006 Published by Elsevier Inc.