Analysis of Change of Cultivated Land and Grain Production in Hunan Province

[Objective] This paper aimed at exploring the countermeasures for cultivated land protection and food security assurance and providing references for the formulation of policies related to cultivated land and grain production of the whole province.[Methods] Data of population,cultivated land,grain and others in Hunan Province during 1989 to 2008 were collected by county（district）.The changes of cultivated land and grain production of the whole province were analyzed using Geographical Information System（GIS）.[Results] The population was increasing continuously,the total area of cultivated land was reducing as a whole in spite of increasing in one or two year in one or two county,the total grain production and per capita grain yield was fluctuated within a certain range in recent 20 years of the whole province.The reducing of cultivated land was mainly due to the industrialization and urbanization development.The unbalanced quantity and quality of cultivated land,various natural disasters,readjustment of industry structure and inner readjustment in the agriculture,variety improvement and improvement of cultivated technology mainly affected of the grain production.[Conclusions] The protection of the quantity and quality of cultivated land has to be strengthened to ensure food security.It is important to enhance the ability of resisting drought and flood disasters by improving the construction of agriculture establishment in order to insure the productivity of cultivated land,to increase farmer’s enthusiasm for growing grain with favourable food policy,to improve the per unit area yield of grain by variety improvement and to increase grain sown area by enlarging the double-cropping rice sown area.

Changes in Cultivated Land Resources and Grain Potential in China's Mainland between 1996 and 2007

Analysis of recent changes in the amount and nature of cultivated land and grain potential, and the impacts of these changes on grain security in China's Mainland provides vital information for revising and developing strategies regarding protection of cultivated land and national grain security. This study examined changes in the area of cultivated land and in grain potential in agro-ecological zones using the "change rate" method. Agro-ecological subzones were used as the basic units and agro-ecological zones as the research units. We then studied changes for all of China's Mainland using the "gravity centre model" and analyzed the structural change of cultivated lands in each agro-ecological zone to investigate the changes in detail. The results show that both cultivated land and grain potential in China's Mainland decreased from 1996 to 2007. The structural and quantitative changes in each zone have caused the shift of the gravity centres of cultivated land and grain potential in China's Mainland to the northeast. Unfortunately, it is unlikely that natural and economic resources can keep up with this change. Although a large gap remains between the grain potential and the actual grain yield, the rapid loss of grain potential and the direction of change pose great threats to grain security. To ensure comprehensive grain security in China, it is vital to rethink the regional patterns of grain production according to natural conditions without jeopardising cultivated land protection(quantitative and qualitative), and consider the direction of cultivated land use and reconstruction according to local natural conditions, water and soil resources, and the level of economic development, and then work steadily to improve the grain potential.

Performance evaluation of ecological compensation policy for cultivated land in China

The paper evaluates the changes in the ecological environment of cultivated land in the major crop-producing areas major crop-producing areas in the past 20 years by constructing an ecological pollution index;and quantitatively analyzes the effects of the existing policies and their main influencing factors by applying the PSM-DID method based on the frequency of policy enactment.The results are as follows:first,the existing ecological compensation policies for cultivated land are effective but not significant in improving the ecological environment in the major crop-producing areas.The economic development level and grain cultivation area of the major crop-producing areas are significantly and positively correlated with the improvement of the arable land ecological environment,while the level of agricultural infrastructure construction is significantly and negatively correlated with the improvement of the arable land ecological environment.Second,the reason for the ineffectiveness of the current arable ecological land compensation policy in protecting the arable land ecological environment in the main grain-producing regions is that the existing arable ecological land compensation policy in China has its own institutional defects and needs to be further improved.At the same time,the level of environmental pollution of cultivated land in the main grain-producing regions is positively correlated with the level of income from cultivated land and cultivated area.

Characteristics of Steep Cultivated Land and the Impact of the Grain-for-Green Policy in China

The Grain-for-Green Policy in China could not only improve China＇s ecological quality, but also influence grain supplies for a short term. Based on data from the detailed nationwide land use survey in 1996 and the steep cultivated land survey update in 2000, a regression model for the driving forces affecting steep cultivated lands was developed, and cluster analysis was used to identify seven steep cultivated land types in order to analyze the grain availability impact of the project with land usage estimates for 2010 and 2030. The results suggested that consecutive days with minimum daily temperature over 10 ℃ and the dominant slope in a county constrained the spatial distribution of steep cultivated lands. In terms of socioeconomic factors, steep cultivated land was a complex interaction of population size, gross domestic production level, and the richness and quality of cultivated lands having slopes less then 15°. The trends for steep cultivated land in 2010 and 2030 were forecast using a driving forces model and China＇s grain security criteria and showed that the Grain-for-Green Policy at the national level would not cause a grain shortage or threaten food security criteria. However, if steep sloped lands were to be retired from production, some regions would need grain supplements as early as 2010. Also, assuming that only 60% of the cultivated land at the national level was needed, population and economic development pressures in 2030 would require some steep cultivated lands to be used for grain production.

Cultivated-land change in Mu Us Sandy Land of China before and after the first-stage grain-for-green policy

Mu Us Sandy Land(MUSL) of China, as a typical eco-fragile and farming-pastoral transitional region, shows great vulnerability to disturbances from cultivation activity. In this region, the conflict between cultivation activity and environmental protection has not attracted great importance until the implementation of China's Grain-for-Green Policy(CGGP) since2000. Here, using Landsat5 TM/Landsat7 ETM+ images from 1990, 2000, and 2010, we monitor the cultivation activity and land-use/cover changes(LUCC) resulting from cultivation activity in the MUSL region. Based on the data from images, we developed a series of databases of cultivated activity-induced LUCC and use them to discuss comparatively the spatio-temporal evolution trends of cultivation activity before and after CGGP implementation. These results provide evidence for managers to evaluate the implementation effectiveness of governmental policy and the influence of cultivation activity on the ecological environment of the MUSL region.

Grain Production and Cultivated Land in China

ＧｒａｉｎＰｒｏｄｕｃｔｉｏｎａｎｄＣｕｌｔｉｖａｔｅｄＬａｎｄｉｎＣｈｉｎａ￥ＷａｎｇＷｅｎｘｕｅ（ＷａｎｇＷｅｎｘｕｅｉｓＤｅｐｕｔｙＧｏｖｅｒｎｏｒｏｆＳｈａｎｘｉＰｒｏｖｉｎｃｅｉｎｃｈａｒｇｅｏｆｒｕｒａｌｗｏｒｋａｎｄａｇｒｉｃｕｌｔｕｒ...

Changes in Land Use and Agricultural Production Structure Before and After the Implementation of Grain for Green Program in Western China–Taking Two Typical Counties as Examples

Soil erosion becomes a serious environmental problem in the world, especially in western China. An effective management practice called the Grain for Green Program(GGP), which was launched in 1999, aims to reduce soil and water loss and alleviate the ecological environment problem in western China. Two typical counties in western China, the Zhongxian(in Chongqing Municipality) and Ansai(in Shaanxi Province) were chosen to evaluate the dynamic changes of land use and agricultural production structure before and after the implementation of the Program in this paper. The results showed that the cultivated land area was reduced by 7.08% from 1989 to 2003. The cultivated land per person was decreased by 8.42% during 1999-2003. Moreover, the stability index of the secondary sector of the economy was increased from 0.91 in the period 1990-1999 to 0.94 in the following ten years. In addition, the stability index of tertiary economic sector increased from 0.88 to 0.92 in Zhongxian county. Meanwhile, the cultivated land area was reduced by 15.48% from 1990 to 1999. The soil erosion modulus was decreased by 33.33% from 1999 to 2006. Also, the stability index of secondary and tertiary economic sectors was 0.86 in the period 1998-2002. However, it decreased by 77% during 2002 to 2007 in Ansai County. These results imply that the Grain for Green Program had different impact on the two regions. Several effective strategies of soil and water conservation have been carried out to ameliorate the sustainable development of ecological environment and economy in these two counties of western China.

Economic analysis of effects on cultivated land following China's entry to the WTO

Inspired by the phenomenon of heavy reduction in the area of cultivated land following the entry of Korea and Japan to the WTO,countries with a large population and inadequate amount of cultivated land similar to China,this paper raises the problem of the potential effects on cultivated land in China following its entry to the WTO.The paper attempts analysis,using economic principles,of the effects of Chinese WTO membership on cultivated land from four aspects;tariff concessions,quota increment,comparative advantage,and the substitution principle.And the conclusion is mat China's entry to WTO may lead to a reduction in cultivated land.Finally,some countermeasures are proposed to resolve the problem.

基于GlobeLand30数据的中国耕地与粮食生产的时空变化分析

21世纪初期,中国耕地与粮食产量变化区域差异明显,为了解21世纪初期中国耕地与粮食生产的时空变化及粮食生产对耕地面积变化的响应,该文利用2000年和2010年两期30 m分辨率的全球地表覆盖数据(Globe Land30),借助统计分析手段对2000-2010年中国耕地和粮食生产的时空变化和粮食生产对耕地面积的依赖程度进行分析。结果表明:1)中国耕地主要分布在东部地区,研究时段内,耕地与林地、草地和人工表面之间的转换最多,耕地变化的特点是"西增东减,总量减少",面积净减少了104.03万hm2,年均减少10.4万hm2。2)中国的粮食生产主要集中在东北、华北和南方地区。粮食产量变化的特点是"北增南减,总量增加"。3)中国耕地分布的集中程度会影响粮食生产的集中程度,且粮食生产分布的集中程度普遍高于耕地。中国耕地分布重心和粮食生产分布重心的移动方向相反,耕地面积的分布表现出了"南退西移"的趋势,粮食生产的重心则是"北上东移",中国的粮食生产格局已转变为"北粮南调"。4)全国有32.24%县(市)的粮食生产都表现出了对耕地数量的依赖,主要分布在东北、华北、西部、长城沿线、西南和东南沿海地区。中国耕地保护政策的制定和粮食生产的可持续发展应该遵循因地制宜的原则,在粮食生产对耕地变化敏感性高的地区,应该加强对耕地数量、质量的保护和农户种粮积极性的提高,更要重视不敏感地区耕地地力的保护和单产水平的提高,以保障中国的粮食安全。

东北三省耕地利用格局变化对粮食全要素生产率的影响

耕地是粮食生产最基本的要素,当前粮食需求扩大与粮食生产区域性不足矛盾突出,寻求更合理的耕地利用格局来实现粮食全要素生产率的提升具有重要意义。本研究基于土地利用/土地覆被变化(LUCC)遥感监测数据,应用GIS软件提取东北三省2000、2005、2010、2015年耕地利用格局相关数据,同时运用数据包络分析模型估算了2000、2005、2010年和2015年东北三省区域和市域粮食全要素生产率。在耕地利用格局变化分析和粮食全要素生产率测算的基础上,从耕地利用格局变化的角度选取指标构建面板数据模型,定量分析其对粮食全要素生产率的影响。结果表明:东北三省市域粮食全要素生产率4个时期均值分别为0.81、0.78、0.82和0.83,粮食全要素生产率空间分布从最初的相对均匀到局部集聚;耕地转出率和耕地斑块破碎度与粮食全要素生产率呈负相关关系,耕地面积比例、耕地转入率和耕地斑块聚合度与粮食全要素生产率呈正相关关系;东北三省粮食全要素生产率提高主要源于耕地面积增加、林地和未利用地向耕地的转入以及耕地在流域的聚合,粮食全要素生产率的降低主要源于耕地转入减少和建设用地对耕地的嵌入式占用。研究表明,严格规划耕地利用格局、持续开展土地整理、提高耕地聚合度,可在保证耕地有效数量的同时,提高耕地利用格局的集聚性和合理性,促进粮食全要素生产率的提升。

耕地种植结构演变的影响因素与多元路径——基于30个省份案例区的模糊集定性比较分析

基于模糊集定性比较分析法,分析中国30个省份耕地种植结构演变的影响因素与多元路径。结果表明:(1)耕地“非粮化”或“趋粮化”演变是耕地稀缺性、劳动力外出务工、种粮劳动力成本、农地流转规模、种粮土地成本、农业机械化作业和农业社会化服务7个因素联合作用的结果;(2)存在生产要素驱动型和规模局限型两条“非粮化”路径,以及耕地资源丰裕—种粮规模化和土地成本诱导—种粮规模化两条“趋粮化”子路径;(3)种粮土地成本上涨是“非粮化”的重要诱因,农业现代化生产体系是互补因素,能够缓解种粮土地成本压力对粮食种植的不利影响;(4)劳动力外出务工与农地流转规模、农业机械化作业和农业社会化服务等因素相互关联,对耕地种植结构演变发挥联动影响。

高标准农田建设能遏制耕地“非粮化”吗?

把高标准农田建设作为一项准自然实验,构建连续型双重差分模型,基于省级面板数据考察高标准农田建设对耕地“非粮化”的影响及作用机制。研究发现:相较于控制组,高标准农田建设使实验组耕地“非粮化”程度下降了3.64%,表明高标准农田建设对耕地“非粮化”具有显著且持续强化的抑制效应,经过模型适用性和多重稳健性检验后结果依然可信;该政策效应因区域粮食功能定位、粮食熟制、粮食作物种类和地形条件不同而表现出明显差异,粮食主产区、高熟制地区、水稻主种植区和非平原地区高标准农田建设对耕地“非粮化”的抑制效应更明显;地块规模扩张、种植模式变革和比较成本优势是高标准农田建设抑制耕地“非粮化”的三条重要途径。研究结论的政策启示为:在建设农业强国过程中,应加快新一轮高标准农田建设,尽快补齐耕地质量短板;同时严格落实高标准农田利用优先序,彻底扭转耕地“非粮化”势头,为实现“藏粮于地”战略目标提供支撑。

赣东北丘陵地区县域耕地非农化和非粮化驱动机制及预警

[目的]探究江西省上饶市铅山县耕地非农化和非粮化的空间分异特征及其驱动机制,模拟土地利用变化格局以作出预警,为严格落实耕地用途管制措施提供科学依据和决策支持。[方法]以铅山县2017年和2021年的土地利用数据为基础,利用空间计量模型识别耕地非农化和非粮化的驱动机制,借助PLUS模型预测耕地变化情况,根据预测结果进一步划定预警级别。[结果](1)铅山县耕地非农化和非粮化空间分异特征明显,耕地总体变化率和非粮化率高值区聚集在县域北部的河谷平原和南部的武夷山北麓山区,低值区分布在县域东西两侧;耕地非农化率高值区分布较为零散,低值区相对连片。(2)耕地利用等级和人均耕地面积是抑制耕地非农化的重要因素,城乡梯度、道路密度与非农化率和非粮化率呈正相关,人均建设用地面积、耕地后备资源对非农化率存在正向影响。(3)多情景模拟结果显示,自然发展情景下建设用地扩张导致耕地数量大幅度减少,耕地管制情景下耕地连片性提高,生态保护情景下存在林地挤压耕地资源的情况。(4)铅山县耕地非农化处于适度预警以上的行政村主要聚集在县域南部乡镇,耕地非粮化预警级别的高值区普遍集中在县域北部乡镇。[结论]未来应积极推进高标准农田建设,建立耕地保护补偿机制,提高乡镇集约节约用地水平,开展全域土地综合整治,完善耕地流转制度,落实耕地“占补平衡”和“进出平衡”的耕地用途管制措施。

基于耕地资源质量分类监测的土壤条件变化对粮食产量的影响——以河南省兰考县为例

为突出土壤条件变化对粮食产量的影响,采用趋势分析法和对比分析法,以兰考县耕地资源质量分类监测工作为例,分析土壤监测样点不同年份的土壤条件变化对当地粮食产量造成的影响。研究表明,土壤有机质含量的增加和土壤pH在合理范围内的增加都能够提升粮食产量。建议以测土配方施肥为基础,增加有机肥的使用量,提升土壤有机质含量,并针对当地土壤的实际情况和主要作物类型,提出有针对性的改良土壤pH的措施,以提升粮食产量。

产销平衡区粮食安全测度与时空特征研究——以云南省为例

[目的]衡量与评估粮食产销平衡区云南省的粮食安全状况,为云南省乃至全国的粮食安全科学探索与地方政府决策提供参考依据。[方法]采用质量系数优化后的耕地压力指数模型对2003—2018年云南省的粮食安全进行定量分析。[结果]从时间上看,云南省粮食安全水平总体上呈上升趋势。从数量上看,16个州(市)中,10个州(市)粮食处于安全状态,占62.50%;6个州(市)粮食安全处于不安全状态,占37.50%。从空间上看,曲靖、大理、保山、红河、文山5州(市)为中度安全,德宏、普洱、临沧、昭通、楚雄5州(市)为低度安全,丽江、昆明2市为低度不安全,西双版纳、玉溪2州(市)为中度不安全,迪庆、怒江为高度不安全,无高度安全地区;粮食安全区域主要集中在云南省东部,其次为西部,粮食不安全区域按不安全程度从高到低依次为东北部、南部及部分中部。[结论]云南省粮食安全形势整体处于不安全状态,但不安全程度较低,属于低度不安全。

安徽县域耕地非粮化时空格局演变及影响因素研究

耕地非粮化研究,对耕地保护与合理使用具有重要意义。结合1998—2022年的相关数据,利用空间分析与数理统计法分析安徽县域耕地非粮化的时空格局演变及影响因素。结果表明:安徽全省和皖北、皖中、皖南的非粮化率都呈现下降趋势;县域耕地非粮化类型具有“一增一减两稳定”的空间演化特征,空间范围变动明显,低度非粮化、中度非粮化占比较大;县域非粮化率区域差异明显并具有高值与低值集聚的空间依赖特征;影响因素存在显著区域差异,按影响力由大及小依次为人均耕地面积>城镇化率>农业从业人口比例>坡度>有效灌溉率。应采取加强耕地用途管理,强化政府监管与市场引导,因地制宜提升粮食产能等措施以防止耕地非粮化倾向,有效稳定粮食生产。

耕地种植用途管控制度研究——基于《粮食安全保障法》相关规定的解析

从《土地管理法》规定“耕地用途管制”到《粮食安全保障法》规定“耕地种植用途管控”,这在一定程度上说明国家层面对耕地种植用途干预的具体方式倾向于更加注重市场机制的功能发挥。耕地种植用途管控事实上意味着国家在寻求耕地内部效益与外部效益之间的平衡,并且嵌入了优化耕地种植结构的立法意图。检视我国的耕地种植用途管控制度可见,国土空间规划存在制度厚度不足、耕地保护利用激励制度存在绩效不彰、耕地种植用途管控存在操作性层面挑战、耕地种植用途管控面临多元价值冲突。完善耕地种植用途管控制度的关键是要厘清政府干预市场的边界,对国土空间规划制度进行调适,补强耕地保护利用激励制度,在此基础上,还需进一步优化农村集体经济组织的管理功能。

“四位一体”如何走向一致:耕地“非粮化”过程中的主体行为逻辑及耦合调适

在国家推进乡村全面振兴和高度重视粮食安全的背景下,耕地“是否种”和“种什么”已成为我国农业生产经营研究的关键议题,梳理清楚耕地“非粮化”过程中各方主体行为逻辑耦合过程意义重大。国家、地方政府、“市场”、种粮主体分别遵循着政治、治理、市场和经济逻辑进行行为选择,但受各方主体关注重心失序、经济利益失衡和对策调和失效等多重因素影响,其行为逻辑互动往往得不到充分耦合,致使耕地“非粮化”困局难以破解。据此,应当引入国家政府层面变量引导各方主体坚定种粮信念、压实国家政府的主体责任、运用政策工具的服务激励作用、探索建立省际横向利益补偿机制、构建政策动态优化循环机制,推进“四位一体”走向一致,化解主体行为目标冲突,有效遏制“非粮化”趋势,使国家粮食安全根基得到全方位夯实。

重庆丘陵山区耕地非粮化时空变异及驱动类型划分

为厘清中国西南典型丘陵山区的耕地非粮化态势和提供有针对性的管控措施,以重庆市为研究区域,基于空间自相关方法、地理探测器、主成分分析和K均值聚类等方法探究重庆市耕地非粮化驱动因素,并划分驱动类型。结果表明:2011—2020年,重庆市耕地非粮化率由37.51%上升至42.87%,中度非粮化和高度非粮化区县共增加了14个;空间聚集程度加深,高高集聚区和低高集聚区主要分布在中心城区。城乡居民人均可支配收入差距、城镇化率、各区县距中心城区距离是耕地“非粮化”主要的驱动因子,各因子交互作用以非线性增强为主,各区县距中心城区距离与城乡居民可支配收入差距两因子交互对非粮化空间格局的解释力最强。重庆市非粮化驱动类型可以分为农业生产支持型、区位经济引导型、农业生产弱化型三类,且分区结果与重庆市“一区两群”规划一致。研究结果可为重庆市耕地非粮化分区管控政策制定提供依据,同时为其他山地、丘陵地区提供借鉴。

碳排放约束下耕地利用推动粮食生产的逻辑关联、现实矛盾与路径优化

耕地利用是国家粮食安全的重要保障,在碳排放约束背景下探究其与粮食生产之间的有机关联有助于揭示“土-碳-粮”三要素复杂的逻辑关系。该研究基于归纳演绎法与理论分析法,在梳理碳约束下耕地利用与粮食生产逻辑关系的基础上,深入分析粮食安全保障与碳减排背景下中国耕地可持续利用面临的挑战,并提出促进耕地绿色转型升级与粮食综合生产能力提高的优化路径。结果表明:1)碳排放约束下耕地利用与粮食生产之间紧密的逻辑关联形成了复杂的“土-碳-粮”要素系统;2)当前农业生产条件下实施耕地利用碳减排对国家粮食安全具有不确定性影响,但粮食稳产与增产仍将造成大量碳排放;3)为有效改善碳排放约束下耕地利用与粮食生产的紧平衡状态,从耕地保护、碳减排、粮食生产三方面通过耕地资源配置优化、碳交易市场构建、粮食生产结构调整等方式实现“土-碳-粮”要素协调路径优化。未来需合理规划耕地空间利用格局,采取多种政策工具,转变耕地利用方式,促进耕地低碳、绿色利用与国家粮食安全的可持续协同发展。