It is important to develop an integrated management for water resource associated with sustainable food production consideirng water enviromental conservation. In China, fresh water resources are increasingly being polluted and depleted, threatening sustainable development and human and ecosystem health. Therefore, we organized a research project to discuss on a possible framework for intergrated analysis of water availability and water polution caused by food production. We focussed on reviewing feature of water resource, water balance and water pollution in China as the initial step of this project. In addition, we have composed a numerical model, which can calculate nitrogen concentration in the Asian major rivers. We adopt cell model, and the resolution is fixed to be 0.5 x 0.5 degree. The model incorporates water balance and nitrogen balance that generated from food supply and consumption process. Nitrogen load from atmosphere is also included in the balance. The total nitrogen load generated in the major river basins is 21.8 [million t/y], currently. Water pollution by nitrogen is serious in the Yellow river even today. The nitrogen load generated from food system must be increased in the 21st century, and water pollution by nitrogen will spread all over Asia.
watershed, sustainability, water pollution, water resources, food production