Spatiotemporal patterns and drivers of cultivated land conversion in Inner Mongolia Autonomous Region,northern China

Protection and optimization of cultivated land resources are of great significance to national food security.Cultivated land conversion in northern China has increased in recent years due to the industrialization and urbanization of society.However,the assessment of cultivated land conversion in this area is insufficient,posing a potential risk to cultivated land resources.This study evaluated the evolution and spatiotemporal patterns of cultivated land conversion in Inner Mongolia Autonomous Region,China,and the driving factors to improve rational utilization and to protect cultivated land resources.The spatiotemporal patterns of cultivated land conversion in Inner Mongolia were analyzed using the cultivated land conversion index,kernel density analysis,a standard deviation ellipse model,and a geographic detector.Results showed that from 2000 to 2020,the trends in cultivated land conversion area and rate in Inner Mongolia exhibited fluctuating growth,with the total area of cultivated land conversion reaching 7307.59 km^(2) at a rate of 6.69%.Spatial distribution of cultivated land conversion was primarily concentrated in the Hetao Plain,Nengjiang Plain,Liaohe Plain,and the Hohhot-Baotou-Ordos urban agglomeration.Moreover,the standard deviational ellipse of cultivated land conversion in Inner Mongolia exhibited a directional southwest-northeast-southwest-northeast distribution,with the northeast-southwest direction identified as the main driving force of spatial change in cultivated land conversion.Meanwhile,cultivated land conversion exhibited an increase-decrease-increase change process,indicating that spatial distribution of cultivated land conversion in Inner Mongolia became gradually apparent within the study period.The geographic detector results further revealed that the main driving factors of cultivated land conversion in Inner Mongolia were the share of secondary and tertiary industries and per-unit area yield of grain,with explanatory rates of 57.00%,55.00%,and 51.00%,respectively.Additionally,improved agricultural production efficiency and the coordinated development of population urbanization and industry resulted in cultivated land conversion.Collectively,the findings of this study indicated that,from 2000 to 2020,the cultivated land conversion in Inner Mongolia was significant and fluctuated in time,and had strong spatial heterogeneity.The primary drivers of these events included the effects of agriculture,population,and social economy.

Estimation of Land Production and Its Response to Cultivated Land Conversion in North China Plain

Food safety and its related influencing factors in China are the hot research topics currently,and cultivated land conversion is one of the significant factors influencing food safety in China.Taking the North China Plain as the study area,this paper examines the changes of cultivated land area using satellite images,estimates land productivity from 1985 to 2005 using the model of Estimation System for Land Productivity(ESLP),and analyzes the impact of cultivated land conversion on the land production.Compared with the grain yield data from statistical yearbooks,the results indicate that ESLP model is an effective tool for estimating land productivity.Land productivity in the North China Plain showed a slight decreasing trend from 1985 to 2005,spatially,increased from the north to the south gradu-ally,and the net changes varied in different areas.Cultivated land area recorded a marginal decrease of 8.0 × 105 ha,mainly converted to other land uses.Cultivated land conversion had more significant negative impacts on land produc-tion than land productivity did.Land production decreased by about 6.48 × 106 t caused by cultivated land conversion between 1985 and 2005,accounting for 91.9% of the total land production reduction.Although the land productivity increased in Anhui and Jiangsu provinces,it can not offset the overall adverse effects caused by cultivated land con-version.Therefore,there are significant meanings to control the cultivated land conversion and improve the land pro-ductivity for ensuring the land production in the North China Plain.

Analysis on the Influencing Factors and Control Measures of "Non-Grain Conversion" of Cultivated Land in Agricultural Land Transfer

Through the method of literature analysis,this paper analyzes the present situation of the"non-grain conversion"of cultivated land in the transfer of agricultural land in China,summarizes the influencing factors and consequences of the phenomenon of"non-grain conversion"of cultivated land in the transfer of agricultural land,and finally puts forward some measures.The study found that costs and benefits are the fundamental factors affecting the"non-grain conversion"of cultivated land in agricultural land transfer,and other main factors include government and policy guidance,industrial and commercial capital to the countryside,labor transfer and so on.The"non-grain conversion"of cultivated land in the transfer of agricultural land is a serious threat to China s food security,leading to the decline of the quality of agricultural land and the destruction of the ecological environment,as well as the risk of breach of contract in"industrial and commercial capital to the countryside".Based on the understanding of the influencing factors of non-grain conversion,this paper puts forward the following measures:strengthening the control of the use of cultivated land in agricultural land transfer;implementing accurate subsidies for grain cultivation and ensuring the benefit of grain growers;adopting grain planting incentive mechanism to increase grain enthusiasm;strengthening media publicity and education to enhance food security awareness.The improvement of the current situation of the"non-grain conversion"of cultivated land in the transfer of agricultural land will be of great significance to the protection of agricultural land and food security in China.

ANALYSIS AND MODELING ON CULTIVATED LAND CONVERSION——Case Study of Hebei Province

： With the acceleration of thc urbanization and industrialization of China, it is inevitable that cultivated land convcrts to built-up land for industrial, commercial and residential uses, which would impose pressure both on food security and on the sustainability of urbanization itself tbr such a country with large population and few cultivated land. Based on thc three-time Landsat Thematic Mapper （TM） digital imagcs and statistic data of Hebei Province, the general facts of cultivated land conversion and its driving forces were analyzcd by establishing econometric model in this papcr. Some conclusions werc drawn as the following： during 1985 2000, the rate of cultivated land converting to built-up arca in Hebei was 4.01% or 0.27% pcr year. Of all the converted cultivated land, 20.96% was converted to built-up area and of all the new built-up areas, 83.4% was converted from cultivated land; meanwhile the conversion is uneven not only in time but also in space; factors such as edgc length shared by cultivated land and built-up land, agricultural value per hectare, non-agriculture value per hectarc, GDP, total population, farmer＇s net income per capita and time had significant effects on this conversion.

Mutual Conversion of Land Use between Urban and Rural Area in the Process of Urbanization: A Case Study of Shandong Province

Urbanization is one of the driving forces for the land use change in type and structure, and its prominent effect is to convert rural land to urban land. This paper takes Shan-dong Province as an example to analyze the current situation of the mutual conversion between the urban and rural areas from the aspects of the structure of land use, the decreasing tendency of the cultivated land, the changes of land use in urban and rural residential areas. It points out that cultivated land is converted to residential area land, industrial and/or mining area land. The relationship between the urban area land and the cultivated land is more direct; meanwhile, the changes of rural residential area lag behind obviously. The decrease of the cultivated land and the decline of soil quality will be the two difficult problems in the process of urbanization.

下辽河平原区耕地非农化时空演变特征及驱动机制

探索耕地非农化的时空演变特征及其驱动机制是耕地保护的前提,分析下辽河平原区2000—2020年耕地非农化的时空演变特征及驱动机制,可以为该地区耕地保护政策的制定与防止耕地非农化提供理论依据。本文基于2000年、2005年、2010年、2015年和2020年5个时期的土地利用数据,以下辽河平原区为研究区域,结合社会经济数据,运用ArcGIS 10.2空间叠加分析,计算耕地非农化面积,采用重心迁移模型、核密度分析、地理探测器等统计学和地理信息系统的空间分析方法,揭示下辽河平原区耕地非农化特征及其演变趋势,并探讨其耕地非农化的驱动因素。研究结果表明:1)在时间上,下辽河平原区耕地非农化面积和非农化率呈现周期性波动,耕地非农化总面积为2201.52 km^(2),耕地非农化率为7.11%。2)在空间分布上,耕地非农化的重心主要从辽中区向东北方向迁移至于洪区,下辽河平原区耕地非农化东部地区高于西部地区,核密度最大值1657.3,主要在于洪区、浑南区、沈北新区、苏家屯区附近;耕地非农化的次集中区域为新民市和昌图县,其核密度最大值分别为1033.18和1018.49。3)在驱动因素上,耕地非农化驱动因素影响依次为农业机械总动力>户籍人口>城镇人口>固定资产投资>第三产业增加值>GDP>粮食产量>第二产业增加值,交互作用探测器表现为双因子增强或非线性增强关系。综合来看,耕地非农化是社会、经济因素综合作用的复杂结果。鉴于此,本文建议通过严格控制城市建设用地占用耕地的规模、挖掘农村居民点利用潜力、转变经济发展方式、推动农业产业结构调整等措施治理耕地非农化。

县域耕地非农化时空演变特征及动态趋势研究——以安徽省为例

耕地是国家粮食安全的物质基础,把握耕地非农化的时空演变规律及动态趋势,对保障粮食供给和可持续发展具有重要意义。以安徽省为研究对象,基于ArcGIS、GeoDa和Matlab软件,提取安徽省1995—2020年耕地非农化数据,在县域尺度上,采取探索性空间数据分析方法研究耕地非农化时空演变特征,运用MarKov链分析耕地非农化的动态演变趋势,为合理管控耕地非农化提供科学依据。结果表明,安徽省耕地非农化面积高值区主要位于安徽省中部(合肥都市圈)重点发展区,低值区主要集中在安徽省北部和南部一些经济欠发达地区,空间集聚性呈先减后增再减趋势,集聚效应逐渐减弱,冷热点区在空间上形成了“块状热点集群”和“点状冷点集群”。安徽省县域耕地非农化水平的趋势主要表现为:不同等级间不够稳定,易发生转移;等级转移基本发生在相邻类型之间,较少出现“跳跃式”转移;考虑空间因素后发现,相邻县区差异化的耕地非农化水平对本县区发生等级转移的概率有不同程度的影响,随着空间溢出效应增强,维持原等级的概率越低,更易发生转移;等级转移的概率同时受空间滞后类型和初始等级的影响。

1990—2020年滇中城市群耕地非农化时空变化特征及驱动机制

[目的]通过分析滇中城市群30年耕地非农化的演变路径、时空变化特征及驱动机制,为滇中城市群耕地资源的保护及精准管理提供理论依据。[方法]基于滇中城市群土地利用数据和统计年鉴数据,运用重心迁移模型、变化轨迹模型、空间自相关分析、主成分分析等方法揭示1990—2020年滇中城市群耕地非农化过程、空间分布特征及主要驱动因素。[结果](1)从时间上看,滇中城市群耕地非农化面积呈波动下降趋势,2000年前后由年均增加约6.88×10^(3)hm^(2)转变为年平均减少约2.66×10^(4)hm^(2),受政策、经济和城市化影响导致其变化最剧烈。从空间上看,耕地非农化集中分布于滇中城市群的中部、东部、东南部和东北部地区。(2)30年来,滇中城市群耕地非农化在空间分布上趋于均衡,区域间耕地非农化差异变小,空间格局趋于稳定。(3)滇中城市群耕地主要转出为林地和草地,少部分转化为建设用地,变化型耕地中有54.60%与草地相关,29.33%与林地相关,4.64%与建设用地相关,主要发生在滇中城市群的中部、北部、东南部和西北部的局部区域。(4)滇中城市群耕地非农化存在显著的空间聚集效应,以高—高聚集和低—低聚集为主,高—高聚集主要分布在中部、北部和东南部,低—低集聚主要分布在西北部、西部和西南部。(5)滇中城市群耕地非农化受社会经济和自然条件共同影响。社会经济中的农业人口、国有固定产投资和城市化率是耕地非农化最主要的驱动因素,影响系数分别为-0.18,0.11,0.10;而自然因素年平均降水量和年平均气温在耕地非农化空间分布和扩张过程起着关键性的作用,影响系数分别为0.17,-0.15。[结论]研究结果揭示30年来滇中城市群耕地非农化的时空变化特征、演变路径及驱动机制。对合理利用和保护耕地资源,保障云南省粮食安全具有重要作用,在一定程度上可为滇中城市群的耕地保护和耕地布局优化提供决策参考。

耕地非农转换空间非均衡测度及空间扩散路径分析——以武汉城市圈为例

基于武汉城市圈48个区(县)2000—2020年5期土地利用变化数据,采用洛伦兹曲线、基尼系数测算武汉城市圈耕地非农转换空间非均衡程度,并利用重心模型绘制基于耕地非农转换速度的分级重心曲线,分析耕地非农转换空间分布特征及时空扩散路径。结果表明:(1)武汉城市圈耕地非农转换速度呈现中部高,四周低的总体特征。(2)耕地非农转换速度空间分异特征明显,不同时期耕地非农转换最快的区域均集中于武汉市及黄石市下辖区县。(3)武汉城市圈耕地非农化在县域尺度上空间分布极不均衡,且非均衡程度有先下降后逐步上升的趋势,其中2005—2010年非均衡程度最低。(4)2000—2020年不同时期耕地非农转换速度分级的重心集中分布于武汉市洪山区、蔡甸区、江夏区、江岸区以及鄂州市的鄂城区。(5)武汉城市圈耕地非农化重心空间迁移方向为西北—东南—西北,其空间扩散路径整体呈现回旋状。该研究实现了武汉城市圈在县域尺度耕地非农转换方向和均衡性的动态可视化,为协调土地非均衡发展和促进区域均衡发展提供了一定科学依据。

新形势下耕地资源质量分类与等别转换的应用研究——以济南市为例

以济南市为研究区域,在2021年度耕地资源质量分类成果的基础上,运用改进的灰靶模型和指标赋分求和法2种等别转换方式将济南市耕地资源质量分类成果转换为等别数据。结果表明:改进的灰靶模型兼顾了耕地的自然本底特征和耕地的粮食产能,在赋权和评价过程更为客观、科学,转换后的等别成果更为合理,济南市质量较好的耕地主要位于中部和北部平原地区以及沿黄地区,等别主要为3等和4等地,占总耕地面积的77%,符合济南市实际情况;采用指标赋分求和法转换的等别整体较为合理,但主观性较强,评价结果区域内部差异性较小。因此,改进的灰靶模型在耕地资源质量分类与等别衔接研究中应用性更强,转换成果可为耕地占补平衡与进出平衡等实践应用提供参考。

土地资源管理中县级国土空间总体规划编制问题及对策

针对南华县国土空间总体规划中耕地“非农化”“非粮化”、用地布局缺乏科学性等问题,通过采取工程措施与调出补划相结合的方式,调整规划分区规则以及分类型、分区域布局新增建设用地等措施,使永久基本农田中的“非耕地”面积减少了149.02 hm^(2),农田保护区面积增加了9 607.35 hm^(2),城镇开发边界和村庄建设边界外的新增建设用地规模由6 044.02 hm^(2)下降到417.83 hm^(2)。

2022年广西林草湿地图斑监测底图处理方法

森林、草原、湿地图斑监测底图的完善是2022年森林、草原、湿地图斑监测工作的基础和前提。针对国家下发的监测底图存在的共性问题和广西地方管理的需要,提出监测底图处理思路和手段。根据广西2022年林草湿图斑监测工作操作细则要求,基于ArcEngine二次开发技术开发辅助处理插件,实现不同调查单位监测底图统一处理。

喀斯特山区耕地“非粮化”空间分布特征及驱动机制研究--以平塘县为例

基于平塘县2012年和2022年的土地利用数据,探究耕地“非粮化”的空间分布特征并分析耕地坡度、耕地质量、道路距离、居民点距离、水源距离5个因子对耕地“非粮化”的驱动作用。结果表明:(1)平塘县现状耕地为30946.67 hm^(2),耕地“非粮化”面积为20046.68 hm^(2),耕地“非粮化”率为39.31%;中国天眼5 km范围内耕地“非粮化”率达到63.70%,远高于全县耕地“非粮化”率;(2)耕地“非粮化”变为林地的面积为17080.00 hm^(2),变为园地的面积为2826.66 hm^(2),两者共占耕地“非粮化”面积的99.30%;(3)随着耕地坡度增加,耕地质量降低,离居民点、道路、水源距离增加,耕地“非粮化”率均显著上升。耕地坡度、耕地质量、居民点距离、道路距离、水源距离5个因子对耕地“非粮化”的影响权重分别为0.34、0.26、0.17、0.13、0.10,其中自然条件因素对耕地“非粮化”的影响权重达0.60,是引起耕地“非粮化”的主要原因。

Impacts of Cultivated Land Conversion on Environmental Sustainability and Grain Self-sufficiency in China

Using provincial data, the present paper examines the impact of cultivated land conversion on agriculture and the environment. It is found that the grain production center is gradually moving towards more fragile and water scarce areas, putting more pressure on the environment. Land conversion caused large losses in ecosystem service values in the 1990s, but large scale ecological restoration programs have been implemented since 2000 to compensate for such losses. The ecological restoration programs are concentrated in regions with relatively low land productivity, whereas cultivated land conversion usually takes place in areas with relatively high land productivity. Newly-cultivated land, especially that in areas marginally suit for agricultural production, is likely to have much lower productivity levels than the original cultivated land. Because the stock of potentially cultivable land is almost exhausted, China＇s grain self-suffiency policy can only be maintained by preserving the available stock of arable land and increasing its productivity in a sustainable way.

综合“同质等效—流补平衡”的耕地“进出平衡”管制:方法与实证

研究目的:明确耕地“进出平衡”的管制体系,构建综合“同质等效—流补平衡”的管制框架,为科学制定农用地用途管制规则、合理确定耕地“进出平衡”管制要求提供参考。研究方法:逻辑推理法和案例分析法。研究结果:(1)耕地“进出平衡”应以一般耕地和可恢复非耕农用地为对象,综合“同质等效”与“流补平衡”的管制要求,实现耕地长期稳定利用的目标;(2)以“同质等效”和“流补平衡”为管制评价依据和分区划定原则,可为落实区域耕地“进出平衡”提供方法支撑;(3)宜兴市永久基本农田外的农用地可划分为备选补入区(2848.07 hm^(2))、备选流出区(2847.70 hm^(2))、重点保护区(3063.06 hm^(2))和特色发展区(16286.94 hm^(2))4种类型,落实耕地“进出平衡”管制后宜兴市耕地耕作适宜性均值可由0.60提升至0.64。研究结论:明确耕地“进出平衡”管制规则有助于落实耕地保有量和明确耕地利用优先序,并且实现耕地的量质并提、格局优化和功效改善。

耕地“非农化”的时空格局演变及其驱动因素研究——基于影响分析与组态分析的双重视角

研究目的:探究中国耕地“非农化”时空演变特征及其压力、状态与响应因素的多重并发影响和因果组态复杂机制。研究方法:基于多元线性回归模型、时空地理加权回归(GTWR)模型的影响分析和基于模糊集定性比较法(fsQCA)的组态分析。研究结果:(1)2004—2020年中国耕地“非农化”面积总体呈增长态势,不同地区、不同类型城市和不同单元分别表现出“东多西少”“阶梯递增”“中西扩散”特征。(2)社会经济驱动因素对耕地“非农化”的影响体现出明显时空异质效应,其中人口城镇化、土地城镇化和产业结构是普遍性的因素。(3)压力、状态与响应中单因素并不构成影响耕地“非农化”的必要条件,不同地区耕地“非农化”的实现是诸多因素构成的不同组态构型并发协同作用的结果,但在不同组态构型的核心因素和辅助因素会发生角色和地位的转换。研究结论:耕地“非农化”受经济、社会和资源配置等多重因素影响,地方政府在制定调控管理政策时需着眼于不同组态路径中压力、状态及响应多重条件的适配关系,加强城市建设占用耕地的空间规划管控。

耕地“非粮化”现状及其原因分析——以思南县杜家寨村为例

随着我国乡村振兴战略的深入实施,城市化、工业化快速扩张,耕地被大量占有、挤压,耕地“非粮化”速度也越来越快。耕地“非粮化”作为影响粮食安全的重要因素,已成为亟待解决的社会热点问题。本文通过问卷调查深入了解思南县杜家寨村耕地利用现状,并使用二元Logistic回归分析耕地“非粮化”产生的原因。结果显示,杜家寨村耕地“非粮化”率为43.80%,所有驱动因子中影响最大的是土地流转,其次是家庭类型,然后是经济作物价格,最后是种粮补贴。基于此,本文提出以下对策建议:(1)降低耕地破碎化,开展规模经营;(2)增加种粮补贴,提高农民种粮积极性;(3)积极推进土地合理流转,加大流转用途监管;(4)强化村集体组织监督,引导农民合理利用耕地。

安徽省耕地非农化的时空演变特征及迁移路径

研究目的:为有效应对安徽省耕地非农化问题,探究县域耕地非农化的时空演变特征及迁移路径。研究方法:以1990-2020年共7年的安徽省LUCC数据为基础,借助ArcGIS软件,引入重心模型、标准差椭圆模型,探究耕地非农化的时空演变及迁移路径。研究结果:1990-2020年期间,安徽省县域耕地非农化重心空间路径表现为“y”型形态,呈现出先远离后靠近的态势。研究结论:揭示了安徽省县域耕地非农化近30年来的时空演变及迁移趋势,以期为政府部门掌握耕地非农化趋势提供一定参考,从而更好保护耕地。

祁连山北坡亚高山草地退耕还林草混合植被对土壤碳氮磷的影响

土壤有机碳、氮素和磷素是生态系统中极其重要的生态因子,土地利用变化将会引起土壤中碳、氮、磷等元素含量的变化。以祁连山北坡亚高山草地区域内三种利用方式（自由放牧天然草地、开垦20年的燕麦（Avena nuda）耕地、退耕8年的还林草混合植被）的土壤为研究对象,通过采集0~30 cm的土壤,分析土壤的理化性质得到土壤碳、氮、磷的含量,再将其转换为土壤碳、氮、磷储量,分析三种利用方式下土壤碳、氮、磷储量的差异以及影响土壤碳、氮、磷生态化学计量比的因子,旨在探讨退耕还林草工程对该地区土壤养分的影响。结果表明,3个样地的土壤碳、氮、磷储量差异显著（P〈0.05）,天然草地的有机碳、全氮储量（72.17、6.80 t·hm-2）显著高于退耕还林草地的（66.75、4.96 t·hm-2）和燕麦耕地的（36.61、3.61 t·hm-2）。这是因为,其一,比较而言天然草地受干扰小。其二,对于退耕还林草地和燕麦耕地来说,由于刈割获取地上部分,可能使得从土壤中获取的有机碳和氮素大于归还的。全磷储量则表现为燕麦耕地的（2.51 t·hm-2）显著高于天然草地的（2.17 t·hm-2）和退耕还林草地的（1.96 t·hm-2）。这是因为燕麦耕地中化肥的施用使得磷元素富集起来,所以其储量较高。与天然草地相比,耕种20年的燕麦地0-30 cm的有机碳和全氮储量分别低了35.56、3.19 t·hm-2,年平均减少速率分别为1.78、0.16 t·hm-2·a-1。与燕麦耕地相比,退耕8年的还林草地土壤有机碳和全氮储量显著升高了30.14、1.35 t·hm-2,年平均增加速率分别为3.77、0.17 t·hm-2·a-1。退耕8年的还林草地轻组有机碳比例（10.93%）显著高于天然草地（9.72%）和燕麦耕地（8.61%）。土壤含水量、容重和微生物量碳氮是影响土壤碳、氮、磷生态化学计量的重要因子。总结认为,退耕还林草混合植被对土壤碳、氮、磷库具有重要的恢复和改善作用,但短期内难以恢复到天然草地水平。因此,为了改善和恢复退化的土壤生态系统,应大力实施退耕还林草工程,并保证退耕还林草地具有较长的年限。

农地非农化经济驱动机制的理论分析与实证研究

协调好经济发展和农地保护的矛盾是实现我国社会经济可持续发展战略的重要基础,而农地非农化又是这一矛盾的焦点,合理调控农地非农化需要掌握其驱动因素的作用机理,辨识主导因素。论文从影响土地资源部门配置的社会经济因素出发,构建了一个农地非农化经济驱动机制的理论分析框架,并应用1995～2001年省级数据进行实证分析。初步分析结果表明,人口增长、固定资产投资是农地非农化的主要推动因素;土地利用的比较效益和耕地资源禀赋是农地非农化的基础因素;地方政府的收益以及地方政府的管制应对行为与农地非农化呈正相关关系,而土地的市场化配置程度与农地非农化的面积呈负相关关系。根据上述的研究结果,文章提出了相应的政策建议。