中国北方山区的土地压力及其缓解途径:21个小流域的经验分析(英文)

Land pressure and adaptation are the main factors determining environmental degradation in most of China’s mountainous regions. Little attention so far has been paid to the adaptation strategies based on evaluation of land pressure in these regions. We evaluated the grain production pressure and economic development pressure for 21 small watersheds undergoing soil conservation measures in the northern mountainous region of China, compared the evaluation results with actual production for each of the watersheds, and analyzed the adaptation strategies. The results imply that land pressure was spatially heterogeneous among the sample watersheds, but there was a balancing trend between land pressure and productive capacity for each watershed. Under rising pressure, these watersheds developed a variety of adaptation strategies such as labor migration, increasing fruit and nut production, and expanding rural tourism if possible. These strategies result from evolution of the market economy in China, and persistent development of the national economy determines the variation of environment in these mountainous regions.     

北方土石山区的土地压力及其缓解途径

以北方土石山区27个小流域样本数据为基础,针对流域粮食生产、经济发展和生态保护对土地的需求,构建了土地压力定量评估方法,评估了各流域的土地压力,并将其与实际土地生产力进行了比较,进而从各小流域的经验事实中提取出使两者平衡的有效途径。结果表明,土地压力在空间上具有非均衡性,但相对于土地生产力的相对土地压力则存在空间均衡化的趋势。2000年前后,只有76%的样本小流域能够支撑人均300 kg/a的粮食生产压力,只有约20%的样本小流域能够支撑其经济发展压力,但这些小流域的土地压力最终都得到了有效缓解。劳动力转移、发展经济林果和特色产业等是缓解上述压力的主要途径。     

Land Use Changes of Valleys Based on Topographic Factors in Beijing Mountainous Regions of China*

Land use changes in mountainous regions were greatly enhanced as the rapid development of economy due to the expanded population in developing countries. Acting geographically as the basic unit of mountainous regions, valleys are the primary sites of economic activities. Therefore optimization of land use policy in valleys is of critical important to the sustainable development in mountainous regions. On the basis of land use data in 1995 and 2012, this study explored the changes of land use according to the assessment of varied topographic factors (i.e., altitude and slope) in typical valleys of the Beijing mountainous regions, China. Our results showed that the valley is an efficiently geographical unit to evaluate land use changes in mountainous regions. We also found that major land use changes in mountainous regions of Beijing from 1995 to 2012 were the dramatic losses of grassland to the cultivated and construction lands, while most of these changes took place at the altitude of 0-400m and the slope of 6-15°. Considering the ever increasing economic development in Beijing mountainous regions, the increases of the construction and cultivated lands are inevitable, however, the great changes at a steeper slope imply the need to tailor land use structure coming into line with topographic factors, and suggesting ecological barriers and water conservation must be exercised in the developments of these areas.     

复杂地貌区域生态敏感区综合评价与保护对策--以钦州市为例

复杂地貌区域国土开发受生态环境因素影响较单一地貌地区更复杂,其境内生态敏感区类型较多,且空间分布比较杂乱,不同生态敏感区之间又相互影响。文章选择山、水、林、田、城互为镶嵌的广西钦州市作为案例城市,以小流域为评价单元,建立集“地”、“水”、“绿”三位于一体的评价体系,在遥感和GIS技术的支持下,将单因子定性分级和多因子空间叠加模型相结合,对整个区域的生态敏感区进行综合评价及分区。从研究结果来看,这种评价技术能够较好地反映这些生态敏感区的综合分异规律,有助于当地政府在区域开发中制定更为科学的生态安全防范对策。     

西南丘陵山地区农村居民点土地整理模式——以重庆渝北区为例

通过对样本区域农村居民点布局及土地利用特点的研究 ,从丘陵山地区的自然环境条件和社会经济发展水平的实际出发 ,提出两种土地整理模式 :一是农林综合开发整理模式 ,即居民点闲置土地的复垦利用与抛荒地利用结合 ,与山地区退耕还林等生态建设工程结合 ,进行退宅还林 ;二是新村建设整理模式 ,即由政府对新村统一规划 ,供给道路等基础设施 ,引导农民集中建房的“政府引导型”农村居民点整理模式 ,并对重庆市渝北区新春村的新村建设的运作和效益进行了实证分析。     

基于小波变换和GRNN神经网络的黑河出山径流模型

对黑河山区流域月降水量和气温做Harr小波变换,并作为GRNN神经网络的输入,对黑河出山径流进行模拟和预测验证,效果较好。应用全球变化成果,在不同的气候情景下,对黑河出山径流进行预测。结果表明,黑河出山径流在未来一段时间内,径流量会有一定程度的增加,最终会减少。但模型对气温反应不敏感。去除气温重构的细节系数后,气温也成为一个敏感因素,但径流量却随气温的增加而增加。可推断,引进Haar小波变换的GRNN神经网络模型可应用于径流量对气温不敏感的流域。     

中国山区耕地利用边际化表现及其机理

耕地利用边际化是当前中国山区土地利用主要变化趋势。利用《全国农产品成本收益资料汇编》资料,本文首先分析2003年以来农业劳动力价格快速上涨的背景下,中国农业生产成本的结构变化以及农户的响应,并对比平原和山区农户对劳动力成本上升的响应方式及程度的差异,发现平原地区能够通过大规模的农业机械替代减少劳动投入,进而有效减少劳动力价格上升所带来的影响,而山区因地形条件限制,劳动生产率提升相对缓慢,并与平原地区的差距不断扩大,导致农业劳动力成本占比不断上涨。随着劳动力成本的快速上涨,中国山区耕地边际化特征明显,以玉米为代表的种植业净利润在2013年普遍降至零以下。2000年以来,中国山区土地利用和植被变化表现为耕地面积减少、森林面积增加、NDVI指数增强,而且在省级层次上,山区县范围NDVI变化率与耕地和森林面积变化率分别具有很强的负相关（r = -0.70）和正相关（r = 0.91）,证实了中国山区耕地当前边际化的发展态势。基于以上分析,本文最后对务农机会成本上升、农业劳动力快速析出背景下的山区耕地利用边际化机理进行了总结。这一研究有助于深入认识山区耕地撂荒和森林转型的发展过程。     

浙江省山区综合开发的探讨

山区综合开发必须调整偏农型产业结构,实行合理利用自然资源和旨在使山区人口向山下流动的积极的社会经济政策,摆脱与分散性密切相关的自给自足观念。由于山区物质、信息流动阻力大,城镇发展宜取多核分散型,要注意交通等基础设施的超前建设,改善山区环境。     

1960-2010 年贵州省喀斯特山区陡坡土地利用变化

基于GIS 与RS技术, 以贵州省喀斯特山区坡度大于25°的区域为研究对象, 利用1960 年1:50000 地形图、1990 年Landsat TM遥感影像以及2010 年的环境减灾卫星(HJ-1A/1B)影像, 解译获取1960、1990、2010 年3 个时间点的土地利用数据, 并结合贵州省水文地质图、坡度图进行陡坡土地利用变化分析。结果表明:①1960-1990 年的30 年间, 有林地、灌木林、水体呈减少趋势, 其中灌木林减少的最多, 其次是有林地;而草地、建设用地、裸岩和耕地呈持续增长趋势, 其中草地增加的最多, 其次是耕地。②1990-2010 年的20 年间, 灌木林、裸岩、耕地呈减少趋势, 其中耕地减少的最多;而有林地、疏林地、草地、水体呈增长趋势, 其中疏林地增加的最多。③随坡度增加覆盖比例呈降低趋势的土地利用类型为有林地、疏林地、水体、建设用地和耕地;随坡度增加覆盖比例呈增加趋势的土地利用为灌木林、草地和裸岩。     

基于冲突—适配视角的土地利用可持续性评价

土地利用可持续性评价是土地系统科学与可持续发展交叉学科研究中一个重要内容,对识别区域土地利用与管理问题,制定可持续土地管理决策具有重要意义。本文从土地利用可持续内涵解析出发,提出了一种基于土地系统冲突与适配视角、适用于不同区域与时段的土地利用可持续评价框架,并以2000—2015年长三角地区为例进行实证分析。结果显示：① 基于土地系统外部发展施压及土地系统内部支撑角度,可以构建由“资源子系统冲突”“功能子系统冲突”“承载子系统冲突”“资源—功能适配性”“功能—承载适配性”组成的土地系统结构。并基于静力学平衡方程,通过计算结构支撑性与平衡性得到土地利用可持续性;② 长三角地区各项土地冲突适配指标中,土地系统功能冲突改善程度最高,但土地功能与承载适配程度最低。各项冲突适配指标具有显著的城乡、纬度、海陆空间分异特征;③ 长三角地区包含17种土地系统构型,呈现最稳定与最不稳定构型两极分布多、中间构型数量少的特征。长三角地区土地利用可持续性结果范围是0.20~1.58,其中浙江>安徽>长三角地区均值>江苏>上海,浙江诸暨市、安吉县等实施绿色发展战略地区显著高于江苏连云港市、如东县等实施传统经济主导型发展战略地区。本文可以为分析区域土地系统可持续性、设置土地可持续发展规划目标、探索土地系统转型方向提供思路与方法借鉴。     

中国农村空心化综合测度与分区

随着城镇化进程加快,广大农村地区出现了以土地资源粗放利用、人口过疏化、经济发展动力不足为主要特征的农村空心化现象。论文基于农村土地利用、社会经济发展数据,采用子系统综合评价与层次逐级判断组合研究方法,综合评价了中国县域尺度的农村空心化程度,并进行了地域分区。研究表明:中国农村空心化地域分异特征明显,高值区集中于北方边境和东部沿海发达县域,两湖平原、中部传统农区空心化也较为突出;低值区集中在南疆地区、青藏高原、西南山区等落后山区。按照土地、人口、经济子系统的交互特征,可将全国划分为新疆经济平稳发展型空心化中低值区等10个农村空心化大区,以及北疆农村空心化出现区等47个亚区。研究结果可为有序、分区、分类推进中国农村空心化整治提供科学支撑。     

基于GIS的区域规模化管理评价方法

区域规模化管理指在一定区域内通过生产要素的集聚,形成适度规模,达到有效利用资源,提高经济社会效益,减少环境污染,增强核心竞争能力的方式、方法和过程.区域规模化管理程度的评价可以有效发现区域规模化管理的内部空间差异,对区域整体发展策略有一定的辅助决策意义.本文在建立区域规模化管理评价指标体系的基础上,以山东省1995年和2000年两个时段为例,就区域人口规模化、耕地规模化和经济规模化空间模型进行了研究,并建立了区域规模化管理评价的综合模型.     

基于能值分析与模糊评价的农用地健康评价方法探讨

农用地是自然生态-社会经济复合系统,其健康状况直接关系着区域经济发展与国家粮食安全(产量与品质)。该研究在农用地分等定级数据的基础上,探讨将能值分析与模糊评价相结合建立综合评价模型评价农用地健康状况的方法,提出了包含质量、产能和土壤环境目标的农用地健康模糊评价体系框架;并基于能值分析理论构建了由能值利用系数和农用地压力系数构成的农用地能值指数评价模型,对农用地健康模糊评价结果进行修正,以期实现农用地健康评价结果的区域间可比,为农用地健康评价提供方法借鉴。     

山区农业土地利用模式的设计

本文分析了市场经济条件下我国山区农业可持续发展所面临的问题 ,提出了山区农业土地利用模式的构想。指出影响我国山区农业土地利用模式的因素主要包括自然地理因素、市场因素和土地制度因素 ,特别是市场因素和土地制度因素对于农业土地利用模式设计的影响在新的历史时期尤为突出 ;强调山区农业土地利用模式设计必须遵循自然地带规律性、与农业经济多样化和规模经营相结合、与开拓产品市场相结合的原则 ;以河南省洛宁县为例具体说明了山区农业土地利用模式设计的技术路线。     

Farmland Marginalization and Policy Implications in Mountainous Areas: A Case Study of Renhuai City,Guizhou

Farmland resources in mountainous areas are important for regional food security and ecological security. Studies concerning changes in farmland use in mountainous areas are of considerable significance in China. Here, we analyzed marginalization characteristics of farmland in Renhuai city from 2005 to 2011 and driving factors using land information systems, surveys of farmer households and statistical data. Our results indicate that from 2005 to 2011, 3095.76 hm² of farmland was converted to forest land and natural reserve, accounting for 5.45% of the total farmland area. This suggests significant marginalization of farmland. Marginalization of farmland in mountainous areas was affected by topography, labor forces and effectiveness of land management. Farmland with a greater slope gradient was more likely to be abandoned; among marginalized land in Renhuai, a slope greater than 15° accounted for 62.26%. A high non-agricultural employment rate of rural labor force and annual income per capita of farmer households in mountainous areas were consistent with high speed farmland marginalization. Low land management benefits were the key reason for farmland marginalization. Although farmland marginalization was advantageous for eco-environment protection and sustainable development in mountainous areas, it resulted in inefficient land resource utilization. A win-win model for the exploitation and utilization of sloping farmland should be explored for production development and environmental protection.     

A Functional Land Use Classification for Ecological,Production and Living Spaces in the Taihang Mountains

A combination of rapid industrialization, economic development and urbanization has caused a series of issues such as resource shortages, ecosystem destruction, environmental pollution and tension between human needs and land conservation. In order to promote balanced development of human, resources, ecosystems, the environment, and the economy and society, it is vital to conceptualize ecological spaces, production spaces and living spaces. Previous studies of ecological-production-living spaces focused mainly on urban and rural areas; few studies have examined mountainous areas. The Taihang Mountains, a key area between the North China Plain and Beijing-Tianjin-Hebei area providing ecological shelter and the safeguarding of crucial water sources, suffer from increasing problems of fragile environment, inappropriate land use and tensions in the human-land relationship. However, studies of the ecological, production, and living spaces in the Taihang Mountains are still lacking. Therefore, this study, based on the concept of ecological-production-living spaces and using data from multiple sources, took the Taihang Mountains as the study area to build a functional land classification system for ecological-production-living spaces. After the classification system was in place, spatial distribution maps for ecological, production and living spaces were delineated. This space mapping not only characterized the present land use situation, but also established a foundation for future land use optimization. Results showed that the area of ecological space was 78,440 km², production space 51,861 km² and living space 6,646 km², accounting for 57.28%, 37.87% and 4.85% of the total area, respectively. Ecological space takes up the most area and is composed mainly of forests and grasslands. Additionally, most of the ecological space is located in higher elevation mountainous areas, and plays an important role in regulating and maintaining ecological security. Production space, mostly farmlands sustaining livelihoods inside and outside the region, is largely situated in lower elevation plains and hilly areas, as well as in low-lying mountainous basins. Living space has the smallest area and is concentrated mainly in regions with relatively flat terrain and convenient transportation for human settlements.     

Spatiotemporal changes in Chinese land circulation between 2003 and 2013

Land circulation is an important measure that can be utilized to enable agricultural management at a moderate scale. It is therefore imperative to explore spatiotemporal changes in land circulation and the factors that drive these variations in order to maintain and increase the vitality of the land rental market. An initial analysis of spatiotemporal patterns in land circulation is presented in this study on the basis of data from 169,511 farm households between 2003 and 2013. The rural fixed observation point system advocated by the Chinese Ministry of Agriculture was utilized for this analysis, and Heckman two-stage models were developed and estimated in order to identify the drivers of regional differences in land circulation at the national scale and at the levels of different terrains. The results of this study show that the rate of land circulation in China rose from 15.09% to 25.1% over the course of the study period, an average rate of 0.8%. More specifically, data show that the rate of land circulation in the south of China has been higher than in the north, that the average land rental payment was 4256.13 yuan per ha, and that 55.05% of households did not pay such a fee during the land circulation process. In contrast, the average rent obtained was 3648.45 yuan per ha nationally even though 52.63% of households did not obtain any payments from their tenants. The results show that land quality, geographic location, transaction costs, and household characteristics have significantly affected land circulation in different regions of China. Specifically, the marginal effects of land quality and geographic location were larger in the plain regions, while transaction cost was the key factor influencing land circulation in the hilly and mountainous regions. The signal identified in this study, rent-free land circulation, is indicative of a mismatch that has led to the marginalization of mountainous regions and higher transaction costs that have reduced the potential value of land resources. Thus, as the opportunity cost of farming continues to rise across China, the depreciation of land assets will become irreversible and the phenomenon of land abandonment will become increasingly prevalent in hilly and mountainous regions in the future. The transaction costs associated with the land rental market should be reduced to mitigate these effects by establishing land circulation intermediaries at the township level, and the critical issues of land abandonment and poverty reduction in hilly and mountainous regions should arouse more attention.     

中国土地流转的区域差异及其影响因素（英文）

Land circulation is an important measure that can be utilized to enable agricultural management at a moderate scale.It is therefore imperative to explore spatiotemporal changes in land circulation and the factors that drive these variations in order to maintain and increase the vitality of the land rental market.An initial analysis of spatiotemporal patterns in land circulation is presented in this study on the basis of data from 169,511 farm households between 2003 and 2013.The rural fixed observation point system advocated by the Chinese Ministry of Agriculture was utilized for this analysis,and Heckman two-stage models were developed and estimated in order to identify the drivers of regional differences in land circulation at the national scale and at the levels of different terrains.The results of this study show that the rate of land circulation in China rose from 15.09% to 25.1% over the course of the study period,an average rate of 0.8%.More specifically,data show that the rate of land circulation in the south of China has been higher than in the north,that the average land rental payment was 4256.13 yuan per ha,and that 55.05% of households did not pay such a fee during the land circulation process.In contrast,the average rent obtained was 3648.45 yuan per ha nationally even though 52.63% of households did not obtain any payments from their tenants.The results show that land quality,geographic location,transaction costs,and household characteristics have significantly affected land circulation in different regions of China.Specifically,the marginal effects of land quality and geographic location were larger in the plain regions,while transaction cost was the key factor influencing land circulation in the hilly and mountainous regions.The signal identified in this study,rent-free land circulation,is indicative of a mismatch that has led to the marginalization of mountainous regions and higher transaction costs that have reduced the potential value of land resources.Thus,as the opportunity cost of farming continues to rise across China,the depreciation of land assets will become irreversible and the phenomenon of land abandonment will become increasingly prevalent in hilly and mountainous regions in the future.The transaction costs associated with the land rental market should be reduced to mitigate these effects by establishing land circulation intermediaries at the township level,and the critical issues of land abandonment and poverty reduction in hilly and mountainous regions should arouse more attention.     

西南丘陵山地区土地整理与区域生态安全研究

开展土地整理是实现土地可持续利用的重要途径,不同区域土地整理的目标、任务侧重点各不相同。对于生态脆弱、生态区位非常重要的西南地区而言,其丘陵山地区土地整理的目标必须与区域生态安全的目标相一致。本文从国际国内土地整理的发展趋势以及土地整理目标区域分工的角度,论述西南丘陵山地区土地整理与区域生态安全之间的关系,提出西南丘陵山地区土地整理的首要目标是确保区域生态安全,小流域土地整理是实现该区域生态安全的典型模式。     

青海省贫困山区的脱贫途径

本文分析了青海省贫困山区的现状、特点和原因,提出了尽快使贫困山区群众解决温饱,摆脱贫困,走向富裕的根本途径,就是立足青海实际,以自然条件为基础,科学技术为核心,大力发展商品经济。把脱贫致富建立在科学的、切实可行的基础上。