【作者】 单娜娜；

【导师】 刘卫东；

【作者基本信息】 浙江大学 ， 土地资源管理， 2010， 博士

【摘要】 对于耕地资源稀缺,土地市场化配置失灵的中国来说,耕地保护是土地利用规划最重要的任务,而土地利用规划则是耕地保护的重要手段。中国土地利用规划中的耕地保护目标是各级政府为了解决有关耕地保护问题而采取行动所要达到的目的、指标和效果,具有多元性、层次性、阶段性和地域性的特点。在不同时期、层面以及地域,社会经济发展对耕地提出了不同的要求,耕地的多个功能中的某一项或某几项功能占有主导地位,由此产生了不同的耕地保护目标。全国和省级层面的耕地保护目标不同、各省之间的耕地保护目标也有差异,正是上述特点的体现。选择科学合理的耕地保护目标,是土地利用规划有效实施的前提,也是区域土地利益均衡的保障。本文构建了中国土地利用规划中的耕地保护目标选择体系,通过多目标线性规划、遗传算法、灰色关联度、因子分析等研究方法,进行全国和省级土地利用规划中耕地保护目标的合理选择,并对耕地保护指标在省际间以及典型省的各县之间如何分配进行了探讨。得到以下研究成果：(1)在全国层面上,耕地的生产目标是耕地保护目标选择的主要方向。在城乡居民的社会保障体系不断完善的情况下,耕地的社会保障功能逐渐弱化,生态功能仅在生态脆弱区和城市边缘才能体现,粮食安全问题使耕地的生产功能日渐突出。中国人口众多,粮食需求量巨大。虽然当前国际谷物产量增长趋势明显、国际粮食贸易持续增长,大量的进口粮食仍会对国际粮食市场产生大的冲击。并且国际市场的的粮食供应与中国的粮食需求不同步,很难满足中国的粮食数量和品种的需求。粮食作为战略物资,过度依赖国际市场还会带来国家安全危机。中国当前耕地保护的主要任务仍然是保障不断增长的人口的粮食安全。(2)耕地是土地利用系统中的子系统,耕地保护目标的选择是一个土地利用结构的多目标优化问题。本文利用多目标遗传算法(Gamultiobj),求出耕地保护规模的pareto解集。采用多属性决策中的OWA和CWAA算子进行最优方案的选择,得出不同目标偏好下的耕地保护最佳规模。结合中国这一时期的国民经济发展目标确定了全国层面上的耕地保护目标。耕地保护的定性目标为：以粮食安全为核心,兼顾经济和生态安全。在保有一定耕地面积的前提下,稳步提高耕地质量,确保国内的粮食需求；适当的开发后备耕地资源,防治水土流失,实现耕地的可持续利用。定量目标：到2020年,耕地单位面积粮食产量要达到5250 kg/hm2;耕地面积保持在11948×104 hm2；全国的粮食生产能力不低于63831.39万吨；2020年土地整理复垦开发补充耕地不低于367×104 hm2其中通过开发增加耕地面积不超过40%,整理复垦所需增加的耕地面积不少于220.2×104 hm2。(3)中国各省之间的自然资源和社会经济条件具有很大的差异,迫切的需要差别化的耕地保护政策。省际间耕地保护指标如何分配不但是全国土地利用规划中耕地保护目标实施的重要保障,也是省级耕地保护目标选择的主要依据。本文引入了区域耕地资源位的概念,确定各省在全国耕地利用中所占有的地位。根据耕地资源位进行耕地保护指标的分配和占补平衡指数的计算。耕地资源位高的省区肩负着更重的耕地保护任务,分配的耕地保护指标较多；耕地资源位低的省区承担的耕地保护任务相对较轻,分配的耕地保护指标较少。根据耕地占补平衡指数可以将中国的耕地占补平衡分为四种类型,一是耕地补充能力强、占补平衡指数大于1的省区；二是耕地补充能力强,但占补平衡指数小于1的省区；三是耕地补充能力弱,但占补平衡系数大于1的省区；第四是耕地补充能力弱,耕地占补平衡指数小于1的省区。可以得出,经济发达的省区往往也是农业生产条件好的省区,虽然这些省区耕地资源比较贫乏,在耕地保护中仍然占有重要的地位。耕地占补平衡指数是一个动态的指标,随着劳动力不断的迁移,农业生产条件的不断改善以及建设用地占用耕地的面积发生的变化,该指数都会随之而变化。(4)对全国来说,耕地保护是为了粮食安全,对每个省来说,其目标呈现出多元化的特点。以省际耕地保护指标分配为基本约束,遵循省域耕地的主要功能,从该省对耕地的需求以及耕地保护的能力出发进行耕地保护目标的选择,在保障全国土地利用规划中耕地保护目标顺利实施的前提条件下,提高省级政府的对耕地保护的积极性。新疆作为全国后备耕地资源的储备基地,虽然光热资源丰富,农产品的比较优势明显,但是生态环境极为脆弱,资源性缺水十分严重,协调好农业用水和生态用水之间的关系是耕地能够可持续利用的关键。根据对新疆耕地可利用水资源量的分析以及节水灌溉技术应用的预测,得出了新疆耕地保护的控制面积。新疆耕地保护的定性目标可以描述为：以生态安全为核心,协调好耕地和生态用地之间的矛盾,坚持“以水定地”的原则,在大力发展节水灌溉技术的前提下适当的开发后备耕地资源,稳步扩大耕地规模,实现耕地的可持续利用。定量目标可以描述为：确保411.4×104hm2的耕地保护底线,将耕地保护面积控制在474.3×104hm2以内。(5)县级政府对耕地保护的执行力是省级土地利用规划中的耕地保护目标能否实现的关键。构建各县的耕地保护优势度模型,根据耕地保护优势度对耕地保护指标进行分配。可以得出耕地保护总优势度越大的县市,耕地保护指标上下限的差异就越大,最大的为沙雅县和察布查尔县,耕地面积的差值分别为157305 hm2和38641.92 hm2；乌恰县的耕地保护优势度最低,上下限差距仅为114.05 hm2。这也说明了耕地保护总优势度大的县市,耕地发展的空间大,耕地保护政策的执行也比较灵活。更多还原

【Abstract】 China’s land resources are extremely scarce in comparison to the world average with more than 21 percent of the world’s population living on cultivated land which is less than 10 percent of the total area available on earth. Cultivated land protection is one of the most important aspects in land administration. The object of cultivated land protection is a set of aim, demands and executive consequences of land protection policy. The characteristics include diversity, hierarchy, stage and rationality. Cultivated land plays different roles in satisfying requirement of social and economic development. Based on these understandings, there are discrepant objects between country and province. The rational object of cultivated land protection can ensure effective implementation of land use planning, and balance interests of regional land use.This paper construct the object selection system of cultivated land protection of land use planning. Methods of multi-objective linear programming, genetic algorithm, factor analysis and grey correlation degree are employed. The paper focuses on how to get the rational object of cultivated land protection in the level of national and provincial land use planning, and researches how to assign task of cultivated land protection for provinces and counties of typical province. The following conclusions are drawn through the study:(1)As China is the most populous county in the world, the food security has been a primary concern of researchers and politicians for decades. It is hard to satisfy China’s consumption needs of food from international market. The food security should depend on national grain production.(2)Cultivated land is a subsystem of the land use system. The object selection of cultivated land protection belongs to the multi-objective optimization. The Pareto solution sets of total area of cultivated land are obtained by Multi Objective Genetic Algorithm method. The optimal solution of cultivated land protection is determined by OWA and CWAA in different objective preference. Based on the results and national social and economic development goals, the object of cultivated land protection is set up The qualitative object are drawn as followed:the food security is core goal; the food needs should be satisfied by these ways which are steadily improving quality of cultivated land and maintained a certain amount of arable land; reserved cultivated land should be properly developed for scares water resource and soil erosion; the sustainable use of cultivated land is ultimate goal. The quantitative object is described as followed:by 2020 in China:The yield per unit area of grain is 5250 kg/hm2, the total area is 11948×104 hm2, the food production capacity more than 63831.39×104 tons; the increased area of cultivated land should be less than 40% of total increased area (367×104 hm2) by the way of land consolidation.(3)The land administration has a spatial difference in China. The regional resource-niche of cultivated land is determined by resources endowment, social and economic environment, agricultural technical condition and regional economic position of cultivated land. Based on the resource-niches, protective amount and cultivated land requisition-compensation balance index of the provinces are calculated. The provinces with higher niche will be assigned more protective index. According to balance index, the provinces can be distinguished four types. The first type is the provinces which have great compensation capability of cultivated land and the balance index above 1; the second is the provinces which have great compensation capability of cultivated land but the balance index blow 1; the third is the provinces which have weak compensation capability of cultivated land but the balance index above 1; the last one is the provinces which have weak compensation capability of cultivated land and the balance index blow 1. We can get such conclusions:The provinces which have developed economic but resources shortage are still in important position in cultivated land protection due to superior agricultural production condition. The balance index will be changed with labor, agricultural production conditions and land conversion’s changes.(4)The main task of cultivated land protection is finishing the object of China to province government. Meanwhile they take the press of economic and social development. Xinjiang have the most abundant reserve land resources and poorest water resource in comparison than other provinces. Although photosynthesis-temperature resources are favorable for crop growth, but ecological environment is very fragile. The key to the sustainable use of cultivated land is coordinated confliction between agricultural irrigation water and ecological water demand in Xinjiang. Based on analysis available water resources of cultivated land of Xinjiang and predicting the water-saving irrigation technique level, the control area of cultivated land of Xinjiang was determined. The qualitative objects are drawn as followed:ecological security is core in Xinjiang. The main task is to coordinate the conflict between cultivated land and ecological land. The reserve land wouldn’t be explored until ecological and other water demand is satisfied, and the area of cultivated land should be steadily increasing by developing water-saving irrigation. It is the quantitative object which range of cultivated land area between 411.4×104 and 474.3×104hm2 in Xinjiang by 2020.(5) The model of dominance degree of cultivated land protection was constructed which is a basis to allocation of cultivated land protection indices in county scale. The first and second of dominance degree counties are Sanga and Qapqal. The county with lowest difference is Wuqia. The results indicate that the counties with greater dominance degree have more flexible implementation in cultivated land protection policies.更多还原