The applications of 3s in operational monitoring system of main crops acreage in China

Grain production is of great importance to any country, especially to China where nearly two-thirds of the population lives in rural area. Hence, it is meaningful for local and central governments to get accurate information about main crops acreage in time. Remote Sensing Applications Centre (RSAC), subjugating to the Ministry of Agricultural of China, has been working on monitoring the main crops acreage as operational task and research project for several years. In order to get such information timely, RSAC adopts sampling methods to estimate the main crops acreage every year with the help of 3S(RS-remote sensing, GIS-geographic information system, GPS-global positioning system) while the sampling parameters are acquired through GIS based on background data. Besides, RSAC orders appropriate RS images covering sampling units in certain region according to sampling information displayed in GIS. The key step is crop identification using the ground information with GPS.