【作者】 冉清红；

【导师】 谢德体； 魏朝富；

【作者基本信息】 西南大学 ， 农业资源利用， 2009， 博士

【摘要】 为了保护粮食安全之源--耕地资源,国家三次划定耕地红线,鉴于前两次划定的耕地红线早已突破的经验,我们应该提早研究第三次划定的耕地红线是否一定不会突破,如果耕地红线再次被突破,那么,保障全国城乡居民食物安全的最后防线--耕地警戒值究竟应该是多少,针对食物安全和用于生产食物的耕地警戒值双重约束,尽早地谋划耕地管理对策。近年来,我国城乡居民主要食物消费包括粮食、蔬菜、食用植物油和食糖等4种是耕地生产供给的。本研究基于食物消费需求量结构建立耕地警戒值模型,模型中的5个参数包括居民人均食物消费需求结构、食物自给率、食物的单产、食品作物播耕强度指数倒数和灾害影响系数。全面考虑了多年来我国城乡居民的食物消费需求结构及消费水平的变化,确定符合国情的三种食物消费需求方案;从国内蔬菜、食用植物油和食糖的生产供给--消费比较分析,国内粮食消费以及国际粮食贸易市场上可供我国进口的谷物数量分析确定食物自给率;考虑到耕地数量和质量管理、食品作物的种植面积以及自然灾害对食物生产的影响,选择影响食物单产的主要因素,建立多元线性回归模型预测粮食、蔬菜、食用植物油和食糖的单产,预测分析食品作物播耕强度指数的倒数变化,并确定了灾害影响系数。根据我国的人口--耕地资源国情,集成与综合运用多元回归分析、灰色数列G(1,1)模型、曲线估计模型、灰色关联分析、能值分析理论、MAPGIS成图技术、传统对比分析方法、逻辑思辨方法等多种理论和技术方法,在研究耕地警戒值模型中的各项参数基础上,依据耕地的基本功能--生产粮食、油料、糖料和蔬菜等作物,以我国城乡居民主要食物消费需求分析来预测耕地警戒值,系统研究了全国和31个省级行政区的耕地警戒值,揭示全国耕地警戒值的年变化特征和31个省级行政区之间的空间差异,以及耕地警戒值模型参数、国家和省级行政区两个层次的耕地警戒值对耕地管理的指示功能。本研究取得的结论是:(1)国家耕地警戒值1)国家耕地警戒值的年变化特征。2009～2020年国家人均耕地警戒值在波动中减小,到2020年,根据食物消费需求方案1、方案2和方案3,国家人均耕地警戒值分别为0.0650 hm~2/人、0.0744 hm~2/人和0.0764 hm~2/人,无论按照哪种食物消费需求方案,人均耕地警戒值都大于0.053 hm~2/人;虽然人口总量呈现缓慢增长态势,但人均耕地警戒值减少相对较快,三种不同食物消费需求方案的国家耕地警戒值总量也在波动中呈现下降态势,到2020年,分别为0.9427×10~8hm~2、1.0784×10~8hm~2和1.1074×10~8hm~2。到2020年,要保住耕地红线的可能性很小,在“十二五”的最后一年(2015年),耕地总量可能会突破国务院规定的耕地红线1.2×10~8hm~2;在2020年前,耕地总量在紧张的边缘徘徊,必须保护耕地数量和提高耕地质量,全国的耕地压力变动于轻压力状态与准压力状态之间,有计划地、适量减少耕地数量,不会威胁国家食物安全。2)不同食物自给率和单产对耕地警戒值的影响程度有差异性,粮食自给率与粮食单产是影响耕地警戒值的关键;影响不同食品作物单产的主要因素有差异,粮食和糖料单产量受灌溉条件影响最大,施用有机肥和建立农机动力配套体系是蔬菜生产用地管理的重点,施肥管理是油料生产用地管理的重点。基于国家耕地警戒值的政策性建议在于:构建第三方参与的耕地行为管理模式维护规划工具的严肃性,用好土地整理规划工具缓解耕地数量减少;耕地保护需要发挥农户的作用,应该从耕地管理制度、利益分配制度和深化直接补贴制度等方面,加强对农户耕地保护行为的激励-约束,即从耕地使用权中分离出保护权,授予农户耕地保护权激励农户参与耕地管理,建立农户能从耕地上获利的增产-增收机制激励农户保护耕地,深化农户“粮食生产综合能力”补贴制度激励农户保护耕地,实施严格的农地管理与利用约束机制;从耕地使用权中分离出耕地的农业发展权,农业部门监管耕地农业发展权,激励农业部门参与耕地保护;探索3S技术跟踪监测耕地动态变化、适时管理耕地。(2)区域耕地警戒值1)各省级行政区的区域人均耕地警戒值差异大,当只考虑自然要素对人均耕地警戒值影响时,从三种食物消费需求方案的区域人均耕地警戒值最大值与最小值之间相差的倍数关系来看,方案1介于7.7804倍～7.8109倍之间,方案2介于7.7813倍～7.8055倍之间,方案3介于7.7820倍～7.8109倍之间,耕地警戒值由小到大的排序为:湖南、江西、广西、广东、福建、江苏、上海、浙江、湖北、四川、北京、安徽、河南、山东、重庆、海南、河北、天津、黑龙江、辽宁、吉林、云南、贵州、宁夏、陕西、内蒙古、新疆、山西、西藏、青海、甘肃;在同时考虑食品消费因素的区域差异时,自然因子作用下的耕地警戒值的空间分异出现了明显变化,从三种食物消费需求方案的区域人均耕地警戒值最大值和最小值之间相差的倍数关系来看,方案1介于5.2975倍～5.3164倍之间、方案2介于5.2960倍～5.3118倍之间,方案3介于5.2975倍～5.3125倍之间之间,由小到大的排序变化为:湖南、江西、广西、河南、湖北、四川、安徽、江苏、福建、山东、河北、黑龙江、广东、重庆、海南、吉林、浙江、贵州、云南、辽宁、上海、宁夏、陕西、北京、天津、新疆、山西、内蒙古、青海、西藏、甘肃。2)各省级行政区的区域耕地警戒值总量为各省规划了一个最低耕地保护数量,为基本农田数量划定提供了参考指标;耕地压力具有明显的区域差异,从2006年开始,北京、天津、辽宁、山西、上海、浙江、福建、广东、西藏、陕西和青海等11个省级行政区就已进入耕地压力状态,用于生产食物的耕地总量出现“赤字”,其他省级行政区的耕地总量处于“盈余”状态。分析不同行为主体驱动耕地减少的作用发现,地方政府是耕地减少的直接和间接推动者,可以通过构建以耕地为载体的利益均衡机制和建立粮食主产区动态管理机制激励地方政府保护耕地,即依据不同省级行政区之间的耕地盈余/赤字量,结合政策性退耕还林还草,划定北京、天津、山西、上海、浙江、福建、广东和辽宁省等8个省级行政区向国库缴纳“粮食安全--生态安全补偿金”,约束其耕地进一步减少行为,不同程度地补偿其他省级行政区,激励耕地保护行为;依据耕地盈余/赤字量对粮食主产区动态管理,13个粮食主产区中的辽宁省只具有省内意义,而广西壮族自治区和云南省可以作为国家后备粮食基地来建设。地方政府严格控制耕地减少的驱动力类型是建设占用耕地关口,行政管理耕地的重点是严格执法。因此,耕地警戒值研究对于深化耕地红线的认识有重要现实意义。基于食物消费需求量结构的人均耕地警戒值是评价人地关系重要参考指标,耕地警戒值总量是保护耕地资源的重要参考指标,两者的年变化是客观存在的,不能用一个指标来衡量;耕地警戒值的区域差异也是客观存在的,不同省区之间的耕地警戒值差异较为显著,为基本农田或者耕地保护规划提供了重要参考。更多还原

【Abstract】 Considering limited availability of cultivated land resources, many developing countries face major ? challenges to achieve a sustainable agricultural development and food security. In order to protect the apparent scarcity arable land resources, the red line of cultivated land has been delineated for three times in China. After the two previous red lines were designated, they could not prevent the arable land from decreasing under the protection management. The arable land management plays an important role in protecting the red line designated. We should take an experience in view of the red- line -broken of cultivated land, and consider in advance the third red line drawn on whether it must not be really broken. If the red line of arable land was broken through, the alert value of arable land is viewed as the quantity that how much arable land at least should be protected in order to satisfy the need of urban and rural residents in China for food safety. Due to dual-bound of food safety and alert value of arable land used in the food production we should make a plan and seek countermeasures for the arable land management as soon as possible. There were four major food-producing for supply depending on the arable land in urban and rural residents in China in recent, such as grain, vegetables, edible vegetable oils and sugar. In this study, the model of farmland security value was built according to the demand structure of food consumption. And the five parameters of this model included the demand structure of per capita food consumption of China’ residents, the food self-sufficiency rate, the yields of food crops, the tillage intensity index and the disaster coefficient. Considering the changes of food consumption structure and consumption level of demand for urban and rural residents in China, we designed the three programs of the national food consumption needs according to the population - arable resources in China. The rates of food self-sufficiency were determined in accordance with the domestic production-supply and consumption of vegetables, edible vegetable oil and sugar using the comparative analysis. And the grain self-sufficiency rate was predicted according to the domestic grain consumption as well as the available cereal imports from the international grain trade market for China in future. Taking into account the main factors affecting the crops yield, resulting from the quantity and quality of arable land management, as well as the natural disasters and production choices, we established the multiple linear regression models to predict the grain, vegetables, edible vegetable oils and sugar yield, forecasted the last change of the food crops sowing tillage intensity index, and analyzed the decline of the grain yield due to natural disaster to determine the disaster index. The purpose of this paper was to study the security line of arable land and arable land management in China. It was calculate scientifically the security line of the per capita critical arable area from 2009 to 2020 and analyzed the arable land management to understand the cultivated land security. We used the comprehensive analytical methods such as multiple regression analysis, Gray G (1,1) model, curve estimation model, the restoration of correlation analysis, energy analysis, mapping technology of MAPGIS, the traditional contrast analysis, logical reasoning and other ways to make conclusions. The warning values of arable land in China and the provincial-level administrative regions were calculated. The spatial difference characteristics of the warning value of arable land in national and provincial-level administrative region were revealed. study the warning value of cultivated land, the instruction functions on the major parameters in modeling warning value of arable land to arable land management, the measures of arable land management, problems of the arable land managed by different actors were analysis, then the land management measures were pointed out. And finally the "incentive - bind" mechanism of managing arable land were considered deeply. The main results are as followings.(1) The warning value of per capita cultivated land in ChinaCalculated the security line of the arable land based on food consumption in China, the result showed that the alert value of national per capita arable land would reduce in the fluctuations in future. The warning value of per capita cultivated land in China from 2009 to 2020 was characterized by the different changes in inter-annual. By 2020, the security line of arable land was 0.0650 hectares per person in Program 1, 0.0744 hectares per person in Program 2, and 0.0764 hectares per person in Program 3, no matter what kind of per capita consumption in accordance with the needs of the program would be greater than 0.053 hectares per person; Although population growth has been slow, but the warning value to reduce the per capita arable land is relatively fast consumption of three different programs the alert value of the total arable land has fluctuated downward trend in 2020. The security line of the total arable land was 0.09427 billion hectares in Program 1, 0.10784 billion hectares in Program 2, and 0.11074 billion hectares in Program 3, respectively. With the rise of the productivity, increase of tillage intensity index, growth of available food imports from the international grain market, vigilance value per capita arable land may be reduced. but no matter what kind of the program was given in accordance with the needs of per capita consumption, the alert values per capita arable land are not less than 0.053 hectares per person in 2020.1) The total warning value of cultivated land in ChinaFrom 2009 to 2020 the total warning value of arable land in the provinces provided a minimum quantity of farmland protection for the land planning in provinces, and could serve as a reference of basic farmland demarcated. The most critical significance of the total warning value of arable land in the provinces was to deliver the information of total arable land demand in a future for the land management sectors and the ordinary people of the provincial-level administrative regions, and let everybody have the sense of ahead urgency to cultivated land resources protection in a future so as to participate in farmlandprotection by themselves.2) The red line of cultivated land and the pressure based on food Security in ChinaThe "Red Line" provisions of total amount of cultivated land is difficult to be realized cultivated land protectBy 2020, the pressure of maintaining the "red line" provisions of total amount of cultivated land is too large to keep red line. Although it was even to take the corresponding measures of protection, the possibility would also be less. It would be time for the total arable land to lower than the red line of arable land in 2015.However, in view of the farmland pressure index, vigilance value of per capita arable land may be subject to reduced with improving continuously productivity, increasing tillage intensity index and raising food import from the international grain market. In average the national arable land would not pose a threat to food security and may be basically in a benign state with little pressure by 2020.Therefore, it is necessary to try more effort in farmland protection, and unnecessary to alarm in the quantity of minimizing arable land appropriately and conditionally.The food self-sufficiency rate in different period from 2010 to 2020 in order to ensure that the food supply for the urban and rural residents in future because of the larger amount of grain demand and a limited number of grain supply of available import in the international market. It were to make China decision to need higher self-sufficiency in food security strategy. That is, food security of grain supply for China must be depended on grain production, supplemented by grain imports. Based on correlation analysis between the various parameters and the alert value of arable land, the result showed that food self-sufficiency rate is the focus to ensure food self-sufficiency, and the grain yield per unit area was playing a key role in safeguarding food productive of arable land. Based on correlation analysis between the impact factors and the various food crops productive of arable land, the result showed that the agricultural water management was playing a key role in grain and sugar crop producing, attaching important to should be focus on the fertilization management in oil crops production and the organic fertilizer application and farm machinery in vegetable production. So the arable land management in China and its relative protect policy were of importance under the food security objectives from the international grain trade perspective. The adverse conditions, which affected the control standards to achieve self-sufficiency rate to protect the food supply for urban and rural residents in China, were analyzed. The major barrier factors included the different position of land management and the different understanding on the importance of food from the national government, local governments and fanners, the contradictions between the less profit of agriculture for cheap cereal and the non-high-growth of agriculture income resulted from low- prices for grain when the farmers were lived bad. the size of contract decentralized management that influenced the scale interest of agriculture, lack of motivation policy and lax implementation, the disaster factor that constraint grain production, and so on. Then the policy proposals were pointed out to protect the grain supply for urban and rural residents, and the issues focusing on the establishment of high-performance incentives - and restraint mechanisms, improve the agriculture input and enthusiasm of farmers for growing grain were discussed. And further given a more in-depth description from price regulation and incentives of grain production- income, management, the subsidy incentives of "comprehensive grain production capacity", and the strict implementation of the agricultural land use and management mechanisms.(2)The warning value of per capita cultivated land in the provincial-level administrative regions1) The alert value of regional per capita arable land were different in the provincial-level administrative, considering only the natural elements affected to the warning value of per capita arable land, the difference between the maximum and the minimum warning value of per capita arable land area were from 7.7804 times to 7.8109 times in Program 1, from 7.7813 times to 7.8055 times in Program 2, and from 7.7820 times to 7.8109 times in Program 3, respectively. From 2009 to 2020, in the provincial-level administrative regions, the warning values of per capita arable land were of difference year by year. The differentiation of alert value of per capita arable land among the provinces is likely to be affected by the impact of natural conditions on food production, but also influenced by food consumption demand because of the regional differences constraints. If we only consider the constraints of natural environment, the warning value of the per capita arable land would rise in backward areas, and depress in developed areas. The regional differences of the alert values of per capita arable land between the developing and developed regions areas were to narrow. In a sense, it would cover the facts of less responsibility for the arable land protect because of more consumption need in the developed areas. Taking into account the regional differences of food consumption demand in China, the warning value of per capita arable land would reduce in the backward areas, but increase in the developed regions. Thus, the regional differences of alert value of per capita arable land would be various with the change of food consumption demand.2) The warning value of the total arable land in the provincial-level administrative regions provides a reference indicator for the provinces to plan the minimum amount of farmland protection with the number of designated basic farmland. The arable land pressure was obviously different between the provinces in China. The farmland surplus or deficit associated with the arable stress could be used as reference of choosing the merchandise grain reserve base and compensating the farmland protection and utilization among the provinces. In some provinces, the total amount of cultivated land were "surplus" state and without pressure arable land used in the producing food, Guangxi and Yunnan provinces could be considered as the reserve bases of commodity grain in future. Considering many factors, the eight deficit provinces including Beijing, Tianjin, Shanxi, Liaoning, Shanghai, Zhejiang, Fujian and Guangdong had to compensate the 20 surplus provinces, which provided food export and their additional ecological security and food security of arable land behind net export. In addition, there may be some questions left to continue with this research. For example, how the "paying - compensation" system of the food or ecological security payment could be set up among the provincial-level administrative regions based on the surplus or deficit of arable land so that the regional government with the cultivated land surplus could be stimulated in preserving farmland. How the rate of basic farmland protection in the provinces could be determined in accordance with local conditions. How the rights of development and protection could be isolated on the basic land-use right so as to stimulate the enthusiasm of farmers and so on.Therefore, the research on the warning value of arable land has important significance in practice for us to understand the red line of arable land reset by our government at present. Based on the structure and demand of food consumption, the security value of per capita arable land was an important reference index used to evaluate the relationship between human and land. The total warning value of the arable land is an important indicator of the demand amount aim to the land manages and the arable land resource protecting. In reality, that both of the measurable indicators change over year is objective. In terms of the alert value of arable land, the regional difference among provinces or autonomous regions is also objective and obvious. As the security value of arable land could provide an important reference for the general land planning and the cultivated land or basic farmland protection. Then, the cultivated land should be demarcated as basic farmland protection areas and subject to stringent control according to the general plans for the utilization of land formulated acts of unlawful appropriation of cultivated land or misuse of land should be prohibited. The overall plan for land use was implemented, and the land use management system was strictly enforced, effectively protecting farmland. We should continue to implement and improve the rural household land contract system, manage well the non-agricultural land and prohibit the unauthorized land use and expropriation of arable land in order to get self-sufficient for food safety in China in future.更多还原