Area Division And Mode Partition Of High-standard Primary Farmland Construction In The Southwest Hilly Area

Accompanied with the rapid and continuum developing of economy and population, the urbanization and industrialization has no sign to stop and both the quality and quantity of cultivated land is descending, the conflict between man and land becoming increasingly prominent, national food security is at risk. The southwest region of china, thanks to its complicated topography and fragile environment, has a worse cultivated land condition, with more mountainous and hilly places, the agriculture and rural economy there was severely impeded. The protection of cultivated land now should take quality, quantity and environment into account, so some new breakthroughs is needed. As analyzed above, the construction of high-standard primary farmland generally became a new strategy for national land using and development, which is aimed to improve the environment, protect the cultivated land, ensure the national food security and develop the modern agriculture, promote the process of constructing new village.The construction of high-standard primary farmland is a process that has multiple goals and need to analyze multiple factors. To increase the scientific and rational credibility of the layout of high-standard primary farmland construction, this paper chose four counties and a district of Chongqing as study object, which separately are “demonstration county of high-standard primary farmland construction” and “one of four main core vegetable planning base.” By analyzing the status and problems of cultivated land and high-standard primary farmland and complying the principles of “high natural quality and high construction suitability”, I selected 13 indexes from site conditions, soil physical properties, soil chemical properties, farming conditions to build the farmland quality model and 10 indexes from geographic conditions, spatial form, ecological conditions, economic and social conditions as factors to build suitability evaluation model of high-standard primary farmland construction, by applying Entropy Analysis Hierarchy Model to determine the index weights, approximation to ideal solution to calculate farmland quality and construction suitability and four-quadrant method to conduct the coupled analysis to cultivated land quality and construction suitability. Combining the analysis above and the field research situation, the construction area of high-standard primary farmland can be attained and the construction mode of each area can be obtained. Research indicates as follow:(1) The cultivated land of Tongliang district is relatively concentrated and mainly distributed in flat area, among which the cultivated land of 20~60 possess 39.89% of total cultivated land area, but the scale and mechanization level are low and the infrastructure are inadequate; the protection rate of primary farmland is 87.15% and these standard basic farmland are mainly within range of 0~150, the primary farmland has a good quality but its spatial distribution is uneven and the infrastructure there are not in good condition or inadequate, Roads and irrigation and water conservancy facilities are especially worse, which hinder the high-quality grain industry from escalating into modern industry.(2) The cultivated land quality of Tongliang district can be divided into four grade, the first grade has an area of 23218.23 hm2 and mainly in Pingtan town, Lufeng town, Hufeng town and Dongcehng street, etc. which are typically high-yield areas in the whole district. The second grade has an area of 16949.39 hm2, mainly concentrated in middle and south region of Tongliang district, among which Lufeng town and Pingtan town together possess the biggest proportion. The third grade has an area of 15225.07 hm2,which mainly concentrated in north and northwest region of Tongliang district. The fourth grade has an area of 11168.24 hm2, which mainly in north and southeast region and central-top region of research area. Generally speaking, the cultivated land quality of Tongliang district are in upper middle grade, the first and second grade are of good quality and possess a relatively high proportion of 60.35% of total cultivated land, spatially their are mainly in meddle region, upward the cultivated land quality gradually decreased obviously, downward the cultivated land quality decreasing first and increasing at last.(3) The construction suitability of high-standard primary farmland of Tongliang district can be divided into 3 categories, namely highly suitability, moderately suitability and low suitability. The high suitability zones are in Xihe town, the central and north region of Tongliang district. The moderately suitability zones are mainly in east and central-north region of Tongliang district, a certain amount are in north region as well. The low suitability zones are wide spread, which relatively in northwest, east and the hinterland of south region of research area.(4) The construction zones of high-standard primary farmland of Tongliang district are divided in to 3 classes: the best condition construction area, conditional construction area and temporarily no construction area. “The high suitability and high quality zone” are the best condition construction area, which has an area of 25118.19 hm2 and mainly in the central region, the west shallow hilly region and the middle part of northeast region of the research area, among them Lupo town, Dongcheng street, Hufeng town and Nancheng street together possess a large proportion. “The high quality and low suitability” and “the low quality and high suitability” area is conditional construction area, which has an area of 26506.19 hm2 and mainly in Yongjia town, Jiuxian town, Pintan town, Fuguo town and Shuikou Town, etc. “The low quality and low suitability” area is temporarily no construction area, which has an area of 14936.54 hm2 and mainly in central-south and north region, Weixin town, Daxin town and Weilong town together possess a large proportion.(5) There are 3 kinds of construction mode applied in the high-standard primary farmland construction process of the research area. In high quality high suitability zone: taking modern agriculture mode as the direction of development, through land remediation to increase the partial soil fertility, insufficient road accessibility, inadequate of irrigation and drainage facilities and farmland pollution, along with cultivated land quality improving measures above, by farmland merging to prompt concentrating and shape-regularatng of high quality farmland, so to improve agricultural production layout, maintain and consummate irrigation facilities, establish drainage system, etc. By improving farm infrastructure, developing precision agriculture and mechanic agricultural, the overall economic efficiency of agriculture can be attained. In high quality low suitability area: adopting the mode of protecting environment and improving infrastructure, on the basis of completed irrigation facilities, pay more attention on the construction of farm road and related traffic facilities, along with ecological protection and ecotourism plan, focus on soil erosion and urban wastewater curation, strengthen the regional land and water resources security and carrying capacity, make use of cultivated land according to local conditions so to fulfil the requirements of new village development. In low quality high suitability area: adopting the mode of developing characteristic agriculture. The limiting factor of these region are low soil organic matter content and thin soil plow layer, measures as applying organic manure to improve soil organic matter content and guest soil covering to increase the effective soil thickness, meanwhile, resolving the conflicts in regional economy development and optimizing crop varieties and quality structure, by carrying out characteristic agriculture, achieving a win-win consequence of crop production and economic benefits, and motivating the willingness of investing of farmers, at the same time, attentions should be paid on the protection of cultivated land that are not included in protection region of high-standard primary farmland.