In supporting global change studies and international cooperation in Earth Observation System of Systems (GEOSS), the National Remote Sensing Center of China (NRSCC), Ministry of Science and Technology of the People's Republic of China integrated a series of products from National High-tech Research and Development Program (863 Program) to carry out global ecosystem remote sensing annual reports.
As a part of 2013 Annual Report, Supply situation of  Maize, Rice, Wheat and Soybean is focused on global food security and closely related to agricultural environment protection as well. The result of this report is achieved from the CropWatch system which was established in 1998 by Digital Agriculture Laboratory in the Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences. This system relies mostly on remote sensing techniques in combination with classical ground data and is capable of providing timely and objective assessments of crop condition and production with original and novel methods and indicators. It is now one of important component in the GEO/GEOSS Global Agricultural Monitoring (GeoGLAM) initiative set up by the G20 and served as one of the three global agriculture monitoring systems.
This annual report is based on the monthly and quarterly CropWatch bulletins, which are released by both in hard copy and in web version ( http://www.cropwatch.com.cn/ ). The CropWatch website also provides detailed information on data product and methodology used in this report. The data and report are published at the website of National Integrated Earth Observation Data Sharing Platform ( old.chinageoss.cn../../../ ).