Study On Comprehensive Productivity In The Northeast Region Of China Based On Cultivated Land Classification

Based on results of cultivated land classification project,this paper studies the cultivated land comprehensive productivity of Northeast region of China from a new perspective in order to offer a theoretical basis and technological support for the strategies of cultivated lands protection and food security in northeast region of China.The main contents are as follows:(1)The connotation of cultivated land comprehensive productivity was explained,the join of cultivated land classification and cultivated land comprehensive productivity was achieved,the theoretical system of cultivated land comprehensive productivity and productive potential was established.The calculation model of cultivated land comprehensive productivity and productive potential in different levels was discussed,the best calculation method of cultivated land comprehensive productivity was finally found.(2)According to the natural,social and economic characteristics of different areas,take the indicators area of cultivated land classification factors as study units to calculate the cultivated land comprehensive productivity. According to the seed acreage and output level of grain crops in the northeast region of China,a unified crop was set to be the conversion standard of cultivated land comprehensive productivity to make the results of farmland comprehensive productivity in different indicators areas have the same meaning.(3)Cultivated land comprehensive productivity and productive potential in the northeast region of China is huge.Theory productivity that is the long-term productivity counts up to 580 million tons;Accessible productivity that is the short-term productivity counts up to 180 million tons;Meanwhile,actual productivity counts up to 135 million tons. Theory productive potential reflects the difference between theory productivity and accessible productivity,it stands for the long-term productive potential and counts up to 400 million tons;Accessible productive potential reflects the difference between accessible productivity and actual productivity,it stands for the short-term productive potential and counts up to 45.64 million tons.(4)The higher cultivated land comprehensive productivity in the northeast region of China distributes to the Songliao and Sanjiang Plain with water and heat resources in good condition;The Changbaishan Mountain area in the east and the hilly area in the west have normal productivity with the landform of mountains and hills;The productivity of the Xing'anling Mountain in the north is poor because of high latitude,steep landform and poor condition of water and heat resource.