U.S. and China Unite to Fight Soil and Water Pollution

The United States and China are working together against some common enemies: soil and water pollution. Government and academic institutions from both sides of the Pacific are co-sponsoring the first-ever International Workshop on Monitoring and Modeling Non-Point Source Pollution (NPSP) of Agricultural Lands.

NPSP is pollution that originates from many different sources and contaminates soil and water supplies. Salts, pesticides, toxic trace elements and livestock waste are major NPSP culprits.

During the July 7-11 meeting in Nanjing, China, researchers are exchanging information on the transport of agricultural contaminants, their long-term effect on the environment, the use of computer modeling tools for studying NPSP problems, and state-of-the-art methods for monitoring NPSP from agricultural lands.

Organizers hope to stimulate research in countries battling NPSP and introduce scientists to the latest methods available for dealing with it. Sponsors include the U.S. Department of Agriculture's Agricultural Research Service, the University of California, the Natural Science Foundation of China, Nanjing Agricultural University and the Soil Science Society of China.

NPSP problems can be mitigated with the right tools, according to Rien van Genuchten, a research leader at ARS' George E. Brown, Jr., Salinity Laboratory in Riverside, Calif., and a chairman of the conference. He points to the success many water management agencies have achieved using HYDRUS software.

HYDRUS is a Windows-based computer model that can be used to design irrigation and drainage systems that provide optimal water to crops while minimizing the movement of fertilizers and pesticides to groundwater. Its adoption has resulted in improved water management in many countries, and universities now use it in classes on subsurface flow and contaminant transport.

Van Genuchten, who was instrumental in HYDRUS' creation, recently extended and expanded a cooperative research and development agreement between ARS and the International Groundwater Modeling Center at the Colorado School of Mines to further enhance the software.

ARS is the USDA's chief scientific research agency.