Research On The Cultivated Land Protection In The Yangtze River Delta Based On Food Safety, Economy Development And Ecology Security

The reduction of cultivated land in Yangtze River delta, brings a bad effect on the Land Resources security, food Safety and ecology security, so it's important to do research on the cultivated land protection. Based on the analysis of cultivated land present condition, the relationship among the cultivated land changes in this region , national food safety and regional ecological environment are discussed, the prediction model of cultivated land quantity coupled with food safety, ecology security and economy development is built, at last some countermeasures were put forward. This research makes a thorough inquiry on the Strategy of cultivated land in Yangtze River delta, as a economy developed region, on the background of food safety and ecology security, and the research results have a Significance on the Sustainable utilization and protection of cultivated land. The results was summarize as bellow:1. The State Characteristics of cultivated land in Yangtze River Delta is analyzed. The results show that cultivated land is the main utilization type of farmland, the Proportion of the total area is far higher than the national level, it's the important land utilization type. The per-capita of cultivated land is small, which is only 0.044ha per person, and haven't reached half of national level. The spatial difference of cultivated land is big. Seeing from the scope of province, the proportion of the eight-cities in Jiangsu Province is higher. And seeing from the scope of city, the proportion of cities of Tangzhou, Jiaxing, Yangzhou, Nantong, Zhenjiang is higher than others.2. The changes of Time and Space in Yangtze River Delta is analyzed. Seeing from Annual variation, the cultivated land in Yangtze River delta was reduced year by year. Cultivated land loss has the fluctuation change of 1996-2000, and has the ascension change after 2001. Seeing from the spatial change in the scope of province, cultivated land loss are converged at Eight-cities in Jiangsu province. Seeing from 16 cities, the bigger decreasing amplitude of cultivated land are converged on the south of Jiangsu and Shanghai, and the smaller decreasing amplitude of cultivated land are converged on the region of Zhejiang and the middle of Jiangsu.3. The results show that the cultivated land reduction location in Yangtze River Delta is mainly on Adjustment of Agricultural Structure and Construction Occupation. The source of cultivated land increased is mainly on land development and land arrangement.4. Some problems of cultivated land in Yangtze River land can be drawn that the total quantity of cultivated land reduces continuously and there has a big spatial difference in the region, the per-capita of cultivated land reduces continuously and The land contradiction stands out, Cultivated Land Occupy-Fill Balance can't be reached and resources in support are insufficient, there has a high Load-rate of cultivated land and land quality drops.5. Forecast model of cultivated land is attained by correlation analyses, and the trend of cultivated land change is forecasted. A conclusion can be drawn that high peak value of cultivated land conversion rate will be appeared on the Period of Eleventh Five-Year Plan. Based on national food security judgment, development forecast and the relation between acreage of cultivated lands and national food security, a conclusion can be drawn that reduction of grain yield on account of reduction of cultivated land in Yangtze River Delta have no significant effect on national food security, but the changes of national food security have active effect on the supply of grain yield in Yangtze River Delta. Some suggestions are put forward to protect cultivated land: positive protection policy must be carried on in Yangtze River Delta during the Period of Eleventh Five-Year Plan; protection policy should be turned into strictly control during the period of Twelfth Five-Year Plan. Besides, it is put forward that some countermeasures on cultivated Land protection, too.6. Assessment indicator system of cultivated land change effected on regional ecological environment, weight Value is determined by AHP. Indicator system includes the effect of cultivated land quantity change and quality change. The results show that the impact comprehensive index has an increasing tendency, the value increases from 0.077 of 1996 to 0.737 of 2004, so the pressure degree of cultivated land change on ecological environment is increased year by year. From the proportion of influence degree of cultivated land quantity change and quality change, the value of cultivated land quantity change is 71% of 2004, which indicates the former is bigger than the latter. The pressure degree of cultivated land quantity change is increased, and the pressure degree of cultivated land quality change has a fluctuation increased tendency. The reduction of cultivated land quantity will effect the change of ecological environment directly. For the sake of promoting the regional ecological sustainable development, both of cultivated quantity and quality must be protected.7. The prediction model of cultivated land quantity coupled with food safety, ecology security and economy development is built. Cultivated Land Demand based on food safety is gained by the model of least per-capita cultivated land area. Multi-projects of cultivated land demand are obtained under the setting of two levels of Per Unit Area Grain Yield and Grain Self-sufficient Rate. Cultivated land allowance is determined based on the prediction of the increased quantities and decrement of cultivated land. And under the setting of two levels of intensive utilization of construction land, two projects are obtained. Combined the projects of cultivated land demand and allowance, the best project of cultivated land quantity is selected after evaluated. The result is that the cultivated land quantity of 2010 is about 3.35×10~6ha, and of 2020 is about 3.30×10~6ha.At last, the cultivated land spatial protection strategy by leveling and districting is put forward. Such as emphasis on the quality protection of cultivated land, protecting eco-landscape function, increasing the exploitation of reserve resource, reducing non-agricultural cultivated land occupation, strengthening the policy management, etc. Then such policy is put forward as promoting and improving the compensation system of cultivated land, carrying on the balance between quantity and quality of cultivated land.