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141.
[目的]耕地整理适宜性评价是土地整治规划的基础,可以为划定耕地整理重点区域、确定耕地整理项目和整理时序提供依据。[方法]文章以位于太行山区的涞源县为研究区域,以现状耕地图斑为评价单元,经独立性分析后选取地形坡度、表层土壤质地、灌溉保证率、耕地系数、与道路距离、与城镇中心距离、地质灾害易发性7个评价指标,运用贝叶斯概率模型计算各指标权重及未整理耕地的整理后验概率,并得到研究区未整理耕地的适宜性空间分布。同时根据改进的障碍因子诊断模型,分析了各适宜整理区的障碍因子并提出相应的整理措施。[结果](1)在影响涞源县耕地整理的各因素中,影响程度从小到大依次是表层土壤质地、与城镇中心距离、耕地系数、地形坡度、与道路距离、地质灾害易发性和灌溉保证率;(2)在涞源县未整理耕地中,高适宜整理区与较适宜整理区占未整理耕地的20.79%,可作为涞源县下一步耕地整理的选择;(3)制约涞源县全域耕地质量的障碍因子是灌溉保证率,整理过程中应根据实际情况科学寻找灌溉水源、结合地形条件采用蓄、引、提相结合的方式合理布设农田水利设施,提高水资源利用率。[结论]该文可为太行山区更科学合理地开展耕地整理项目提供依据。  相似文献   
142.
本文基于边际等值原理,综合城市经济效益、社会效益、环境效益以及建设效益,构建多因子城市建设用地最优规模决策模型,并结合我国城市建设用地供给实际进行分析。结果显示:2001~2015年,我国城市发展经历了从建设用地短缺到最优及至过剩的过程,对建设用地增长的强依赖逐渐转变为弱依赖。城市建设用地增长与边际建设效益弱相关;与边际经济效益之间呈库兹涅茨倒U型曲线关系;与边际社会效益呈正相关、边际环境效益呈负相关。目前我国城市建设用地已经达到最优规模,其中建设用地供给与经济发展失调,是导致净效益下降的主要动因。  相似文献   
143.
In the 1990s, the Democratic People’s Republic of Korea (North Korea) suffered from severe food shortages and large-scale deforestation, which triggered a stage of rural conservation reform. Since 2004, with support from the Swiss Agency for Development and Cooperation (SDC), North Korea’s Ministry of Land and Environmental Protection (MoLEP) has implemented a Sloping Land Management Program (SLMP). The SLMP established sloping land user groups and granted these groups the right to use marginal land for agroforestry development. This devolution of land rights from state control onto local groups is a landmark in North Korea, and this decentralization initiative has now expanded to over eight counties to involve thousands of households. It has also led to the launch of a National Agroforestry Policy and Strategy. Drawing from both qualitative and quantitative data collected from 2008 to 2014, this paper documents the process and effects of the SLMP. It argues that the decentralization reform in land management has contributed to not only food security with increased food crop diversity and productivity, but also notably forest recovery through an expansion of tree plantations and agroforestry practices on degraded sloping lands. However, an insufficient power transfer in the form of a lack of timber rights granted to the local user groups has hampered the effectiveness of the SLMP. There are also institutional and geopolitical challenges that are limiting further scaling-up of land-use decentralization across the country. The policy implication calls for more international investment as well as national land-use policy reforms in order to promote and facilitate further decentralization of sloping land management and to secure greater use rights for sloping land user groups.  相似文献   
144.
The planned economy system’s previous form of industrial land market control in China has led to current market failure because of a large amount of industrial land being sold at a very low price, causing extensive overuse of land and negative effects on land management. As the “World Factory”, the Pearl River Delta (PRD) is well known for its rapid urbanization largely driven by Foreign Direct Investment in labor-intensive industries. A low-land price strategy has been commonly adopted by the local government in order to attract industrial investment. In the past decade, the PRD has increasingly faced the increasing competition from its neighboring competition from its neighboring countries in Southeast Asia that have established preference policies to attract FDI and foreign enterprises. Despite a growing body of literature on the internal forces of industrial land in China, little is known of the external forces involved except for the importance of FDI and the intensity of interregional competition between China and other countries in attempting to attract foreign investment. This research fills the knowledge gap by modeling the situation in the form of an international cooperative game model aimed at revealing the industrial land price formation mechanism between the PRD region and Southeast Asian regions. The conditions of industrial land in the area and several Southeast Asian countries are first analyzed for their industrial land price movements in recent years. A game theoretic model is then built that exhibits similar characteristics. The result indicates that the governments’ low land price strategy and the competition between the PRD and its neighboring countries have created unnecessarily high social and environmental costs. Policy suggestions are made to encourage a more appropriate use of industrial land in China, and the most important being the need for a mindset shift from competition towards coopetition between the PRD and Southeast Asian regions.  相似文献   
145.
[目的]分析小农户合作生产意愿及其影响因素,以促进小农户发展多样化的联合与合作,提升小农户组织化程度。[方法]首先分类分层确定样本县、样本村,随机分类确定样本户,然后通过访谈和问卷调查获取农户数据,并利用描述性统计和Logistic模型对农户数据进行分析验证。[结果](1)农户土地经营规模小,种植结构单一,非农收入比重高,农业兼业化严重;(1)描述性分析表明,土地规模、人均农业纯收入、农机、农业社会化服务、县域经济、土地转出意愿对农户合作生产具有正向影响,家庭人口数量、非农收入对农户合作生产影响为负;(2)Logistic模型分析表明,对农户合作生产有显著影响的因素为非农收入、农业社会化服务支出和土地转出意愿。[结论]小农户合作生产意愿一般,农业社会化服务支出、土地转出意愿对小农户合作生产具有正向影响,非农收入对农户合作生产具有负向影响。  相似文献   
146.
我国耕地保护政策研究:基于背景、效果与未来趋势   总被引:6,自引:0,他引:6  
[目的]我国耕地保护政策对保护耕地、保障粮食安全具有重要意义。研究我国耕地保护政策出台的背景及前后关系、相同政策在不同区域内的执行效果差异,能够为更针对性地提出政策建议提供参考。[方法]主要运用了资料分析和定性描述的方法,首先按照耕地保护政策内涵划分为5个阶段,其次从时间、空间两个尺度,判断了耕地保护政策的数量、质量保护效果差异,最后提出了未来政策出台的方向和趋势。[结果]时间尺度上:1986年、1997年、2004年出台的政策对耕地数量保护的成效明显; 2014—2016年耕地质量保护效果略优于2009—2014年; 目前数量保护成效较好,但质量保护远未达到要求。空间尺度上:耕地数量保护效果西部地区最好,东北地区次之,中部地区优于东部地区; 耕地质量保护效果中部地区最佳,东北地区次之,东部地区优于西部地区。[结论]未来政策可向规范补充耕地全国统筹、完善耕地质量保护法律体系、调动农户保护耕地积极性等方向发展。  相似文献   
147.
Most small-scale social economies are characterised by their deficiency, lack, and/or difficulty in matching natural data. Against this backdrop, this paper builds a relatively uniform theoretical framework and designs a more economical and objective method for demarcating ecological conservation redlines (ECR) based on sensitivity assessment of ecosystem services. The results show that the sensitivity assessment model designed in this study can identify sensitive zones effectively, and that the ECR in Hubei Province are well within the sensitive zones so identified. The delimited areas based on the sensitive assessment of ecosystem services have great similarities (95%) with the actual ECR areas in Hubei Province. The most ecologically important functional zones (EIFZ) can also be identified using the regional ecological sensitivity coefficient. When the threshold of EIFZ is set higher, the probability that it falls within the ecologically sensitive areas is greater and the ECR delimited by the method proposed in this study will be more reliable. Theoretically, the delimitation of ECR can be inserted at any evaluation level with a grid resolution higher than that of the land use data, which can be used as a supplement to the ECR delimitation method in ecology or geography.  相似文献   
148.
基于三维分形的山东省农户分化及耕地利用异质性分析   总被引:1,自引:0,他引:1  
研究目的:揭示农户分化的内在机制及其耕地利用异质性,正确引导农户耕地经营行为和可持续利用。研究方法:基于分形理论建立"职业—收入—耕地规模"三维农户分类体系,开展山东省农户耕地利用调研及实证分析。研究结果:(1)农户间耕地利用行为具有差异性,耕地面积较大的兼业户表现出"高投入—低收益"特征,且农户类型存在动态变化的可能性;(2)经济发展水平较高的城市呈现以"高度兼业户"为主要农户类型的"单核心"分化趋势;(3)农户分化过程除大规模纯农户和高度兼业户的"终点"外,还存在对农业依赖较大的兼业户和耕地面积较大兼业户等"中间态"。研究结论:农户分化过程有律可循,应针对性地制定耕地利用政策加以引导。  相似文献   
149.
在"多项连乘和加总"及向量扩展形式的LMDI模型基础上,构建城镇化进程中人口-居民消费-用水强度的分解框架,分析2003—2016年间水资源消耗的影响因素。研究表明:人口规模扩大和人口城镇化对用水量增长均为正向促进作用,且前者驱动力强于后者;居民消费水平提升是拉动用水量增长的主导因素,而居民消费结构优化升级和居民消费率上升均有效抑制了水资源的消耗,且前者更为显著;用水量的下降主要得益于产业技术进步,生活用水量的增长主要源于生活强度效应。进一步指出未来应合理控制我国人口规模和人口流动,加速居民消费结构的优化升级,注重强化产业技术创新,深挖农业节水潜力,提升居民消费率以实现既定经济规模下的相对节水。  相似文献   
150.
Researchers have spent substantial effort to identify factors influencing pesticide use intensity. However, few studies have compared the relative importance of these factors. This study examines four categories of factors that potentially influence farmers’ pesticide use decisions by evaluating incentivized experiment data, farm survey data, and remote sensing data in China. Our results suggest that land diversification has the largest effect on farmers’ pesticide use. Compared with the most rice-intensive landscape type, less rice-intensive systems cause farmers to spray less on middle rice. Heavy pesticide use intensity is associated with land fragmentation as small-scale farms still dominate crop production. Farmers’ integrated pest management knowledge has significant effects on pesticide use. We also find that loss and ambiguity preferences, rather than risk preferences, are more likely to affect pesticide use intensity.  相似文献   
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