Ecological Functions and Their Values in Chinese Cropland Ecosystem

Cropland ecosystem not only provides people with grains, vegetables, fibers, etc., but also plays an important role in air regulation, soil and water conservation, environmental decontamination, etc. Furthermore, cropland ecosystem has negative effects on our environment, such as soil and water pollution, because of the use of fertilizers and pesticides. So far, there are a few research findings about Chinese farmland's ecological functions, but only a part of ecological functions is discussed in this article. At present, an integrated research is needed in order to get a comprehensive understanding of cropland ecosystem. This article gives a primary result of ecological functions and their monetary values in Chinese cropland ecosystem. The results showed that the total monetary value of ecological functions provided by Chinese cropland ecosystem was 1912.18 billion yuan RMB in 2003 (present price in 2003); the positive value was 2233.41 billion yuan RMB and negative was −321.23 yuan billion RMB. The value per hectare was 18960.60 yuan RMB/hm², of which the value of crop products was 14788.70 yan RMB/hm² and others were 4171.90 yuan RMB/hm². The ecological functions in the farmland vary with regions. The values ranged from 8.68 to 505.08 billion yuan RMB, and HHHR and MLRYR were higher than those of the other ecological zones. The values per hectare ranged from 515.90 to 3498.43 yuan RMB/hm², and SC and MLRYR were higher.