| This research utilizes analyzed datas of soil properties from samples of the second soil survey (the year of1983) and survey of soil fertility (the year of2008) in Fujian province, databases of the Current Land-Use Conditions and cultivated land classification and gradation in Fujian province, and statistics of meteorological observation, population and economy of the year1983and2008in Fujian province, with the aid of the integrated technology of GIS and mathematical model, to respectively evaluate and establish raster spatial databases of economic value, social value and ecological value of cropland in Fujian province in1983and2008and discuss temporal and spatial changes of cropland value in Fujian province and the reason of the changes, based on those results, carrying out study on conversion coefficient of cropland grade value in Fujian province, in order to provide scientific references for balance of cropland requisition and compensation. The results showed that:1. The cropland value in Fujian province had obvious spatial distributional variations, and the laws of the spatial distributional differences of cropland value in the whole province in1983and2008were approximately same. The economic value in1983and2008respectively ranged from27.2thousand/hm2to5007.4thousand/hm2and from80.1thousand/hm2to6023.8thousand/hm2, and the average economic value was1077.0thousand/hm2and1207.7thousand/hm2. The economic value showed that it was high in the southeast and low in the northwest. The social value in1983and2008respectively ranged from387.2thousand/hm2to2542.7thousand/hm2and from252.1thousand/hm2to5136.6thousand/hm2, and the average social value was922.7thousand/hm2and1001.1thousand/hm2. The social value showed that it was high on the coast and low in the mountain area. The ecological value in1983and2008respectively ranged from15.3thousand/hm2to397.6thousand/hm2and from16.2thousand/hm2to492.3thousand/hm2, and the average ecological value was160.0thousand/hm2and198.0thousand/hm2. The ecological value showed that it was high in the mountain area and low on the coast. The comprehensive value in1983and2008respectively ranged from721.5thousand/hm2to6191.1thousand/hm2and from517.2thousand/hm2to7586.8thousand/hm2, and the average comprehensive value was2160.4thousand/hm2and2407.5thousand/hm2. The comprehensive value showed that it was high on the southeast coast and low in the northwest mountain area. The ratio of average economic value and average non-market value of cropland is about1:1. It showed that the social security function and the ecological service function of cropland should not be ignored.2. There were obvious differences of the situation of cropland value variation in Fujian province with time. Between25years, the amplitude of economic value variation ranged from-1895.6thousand/hm2to2277.7thousand/hm2, the average amplitude was130.8thousand/hm2, the average amplitude of the economic value-increased region was216.0thousand/hm2, the average amplitude of the economic value-decreased region was161.0thousand/hm2, and the general trend of economic value variation was that from the southeast to the northwest, the increased amplitude and the decreased amplitude both became less. The amplitude of social value variation ranged from-1263.9thousand/hm2to3027.7thousand/hm2, the average amplitude was 78.5thousand/hm2, the average amplitude of the social value-increased region was402.5thousand/hm2, the average amplitude of the social value-decreased region was152.2thousand/hm2, and the general trend of social value variation was that from the southeast to the northwest, the increased amplitude became less. The amplitude of ecological value variation ranged from-1263.9thousand/hm2to3027.7thousand/hm2, the average amplitude was78.5thousand/hm2, the average amplitude of the ecological value-increased region was402.5thousand/hm2, the average amplitude of the ecological value-decreased region was152.2thousand/hm2, and the general trend of ecological value variation was that the amplitude was high on the southeast coast and in the northwest mountain areas and low in the middle areas. The amplitude of comprehensive value variation ranged from-1813.4thousand/hm2to4409.2thousand/hm2, the average amplitude was247.2thousand/hm2, the average amplitude of the comprehensive value-increased region was516.1thousand/hm2, the average amplitude of the comprehensive value-decreased region was126.1thousand/hm2, and the general trend of comprehensive value variation was that from the southeast to the northwest, the increased amplitude became less.3. In Fujian province, the cropland value of the third to the thirteenth grade was respectively3394.5thousand/hm2,3136.9thousand/hm2,3029.8thousand/hm2,2740.3thousand/hm2,2501.9thousand/hm2,2408.3thousand/hm2,2326.1thousand/hm2,2275.9thousand/hm2,2060.4thousand/hm2,1834.0thousand/hm2and1624.5thousand/hm2. With the decline of the utilization grade index of cropland and grade of cropland, the condition of light, temperature, water, heat and soil quality of corresponding cropland became worse, leading to the decline of economic value, social value, ecological value and comprehensive value of the cropland.4. Taking keeping the balance of quantity between cropland occupation and compensation as the precondition, this paper put forward the conversion coefficient of cropland value based on the grade of cropland, whose principle was keeping occupied and compensated cropland equal in value. When the grade of compensated cropland was higher than the grade of the cropland which was occupied by construction, there was no need for economic compensation and the conversion coefficient of cropland grade value was zero; when the occupied cropland was in the third grade while the compensated one was in the thirteenth grade, the conversion coefficient of cropland grade value was1770.0thousand/hm2and achieved maximum, in other words, not only the quantity of compensated cropland should be the same to that of the occupied cropland, but also the gap of value (1770.0thousand/hm2) between the third-grade cropland and the thirteenth-grade cropland should be paid. And with the chasm of the cropland grade becoming larger, the conversion coefficient of cropland grade value became larger. |
PDF Full Text Request