Human induced land degradation refers to decline or loss of biological or economic productivity resulting from a process or combination of processes, including displacement of soil matreial, terrain
After the publication of Mr. L. Browns article and book Who Will Feed China [1,2] , a series of discussions have been evoked at home and abroad. The present paper will give an in depth analysi
System dynamics is a rigorous method for qualitative description,exploration and analysis of complex systems in terms of their processes, information flows, orgaruzational boundaries and strategies, w