A New Model of Grassland Net Primary Productivity (NPP) Based on the Integrated Orderly Classification System of Grassland

The natural grasslands play a significant but poorly recognized role in the global carbon cycle. Research on NPP of grassland ecosystems is and will continue to be important. In this respect, climate-vegetation models have been drawing much attention and widely applied internationally owing to its simplicity. Grassland types and their distribution pattern could be corresponded with certain climatic types in a series of mathematical forms. Thus, the climate could be used to predict grassland types and their distribution. But there is not a NPP model based on a grassland classification system until now. This paper is to introduce a new model based on the Integrated Orderly Classification System of Grassland (IOCSG), named the classification indices model. The analysis demonstrates that use of the IOCSG and the model to study grassland succession and NPP associated with global climate change is a new research approach.