GIS-based Study On Marginalized Evaluation And Transfer For Cultivated Land

Cultivated land has an effect on national grain security and ecological security,it's the focus of the all social concern and reserch.With the development of global LUCC research,cultivated land marginalization research plays a great role in LUCC research.According to the existing research results,this paper summarizes and analyzes the influence factors of cultivated land marginalization,and then establishs an indicator system based on terrain condition,soil condition,climate condition,geographic condition and socioeconomic condition.An improved TOPSIS method based on connection degree is used to predicate the cultivated land marginalization.Then from the point view of ecological land,the flow direction research of cultivated land is studied with the method of the ananlysis of membershiop degree,neighborhood analysis and comprehensive index model according to its natural suitability,which is used to determin the suitable land use.At last,Ecosystem service equivalent value per unit area in study area is corrected based on net primary procutivity(NPP),precipitation and soil.The corrected ecological service value coefficient is used to evaluate ecosystem service value in this paper.The conclusions are as follows:(1)According to the land use change analysis range from 2009 to 2013,Study area with a total of 2384.23 hm2 cultivated land is outflow.The main flow directions of reduction of cultivated land are forest land(19.2%),transporation land(25.6%),urban villages and industrial land(54.7%),And mainly distributed in Lidu Street,Longqiao Street,Nantuo Town,Lizhi Street,Jiangbei Street,Yihe Town,Jiangdong Street and Xinmiao Town.While a total of 411.72 hm2 cultivated land is inflow in study area and mainly from urban villages and industrial land(92.5%),especially including reclamation of village.Besides,the increasing of cultivated land mainly distributed in Mawu Town,Shituo Town,Longtan Town,Xinmiao Town,Qingxi Town,Nantuo Town,Baisheng Town,Tongle Town and Lidu Street.(2)After analysis,the cultivated land marginalized mainly distributed in the southeast of Fuling and with a total of 6509.74hm2.Analyzing from the administrative unit,the cultivated land marginalized mainly distributed in Wulingshan Village,Damu Village,Lizhi Street and Baitao Street.Analyzing from the site conditions,the area where altitude>1000m,relief amplitude>50m,slope>15°,PH<6,soil thickness <40cm,annual temperature<12?,annual precipitation>130mm,farming radius >500m,irrigation radius >500m,transport radius >500m is much more likely be marginalized.Analyzing from socioconomic conditions,the low average labor force,low average GDP,low average output will promote the cultivated land marginalize.Analyzing from land type,the possibility of dryland is larger than paddy field.(3)After exracting 5%(4652)spots from 2013 land use change survey of Fuling and verifying marginalized cultivated land figure spots extracted from maps and Google Earth images,the correct rate of figure spot extraction of marginalized cultivated land reaches 75.1%.After exracting 5%(245)spots from marginal evaluation of cultivated land and verifying figure spots and Google Earth images,the correct rate reaches 82.0%.The results of research is credibly.(4)After natural suitability analysis,there are 92.9% of marginalized cultivated land suitable for forest land,0.2% of marginalized cultivated land suitable for garden,there are 6.9% of marginalized cultivated land suitable for grass.The total value of ecosystem services after transferring is 2.18 times of before by using corrected ecological service value coefficient.And in addition to food production function decreases,other ecosystem services value rise to different extent.Among them,the hydrological adjusting function,control function and function of climate regulation have bigger growth,while waste treatment function has smaller growth.The research results indicates that GIS technology can be well applied to marginalized and transferring evaluation of the cultivated land,and the research method can achieve good results...