大庆市土地利用/土地覆盖景观格局研究

利用遥感影像处理系统,对大庆市1978~2001年5个时段的TM影像进行处理,得到大庆市土地利用图;据图进行土地利用/土地覆盖景观格局分析,利用GIS软件计算出大庆市区土地利用/土地覆盖的破碎化、斑块形状、分离度、优势度、均匀性及多样性等景观指数,并对大庆市区土地利用/土地覆盖进行自相关分析;结果表明,作为一个典型的石油型城市,大庆市景观格局有其独特之处。     

Farmers’ risk preferences and pesticide use decisions: evidence from field experiments in China

China faces health and environmental problems associated with the use of agricultural chemicals, including pesticides. While previous studies have found that risk aversion affects pesticide use in China, they have focused primarily on commercial cotton farmers. In this study, we consider the case of smaller, semisubsistence and subsistence farmers in a poor and landlocked province of China (Yunnan). We use a field experiment to measure risk aversion and collect detailed data on farm production and input use to specifically ask whether risk aversion affects pesticide use, and whether this effect differs for subsistence farmers producing exclusively for home consumption versus semisubsistence farmers who produce both for home and the market. We find that risk aversion significantly increases pesticide use, particularly for subsistence farmers and for market plots by semisubsistence farmers. Further, this effect of risk aversion significantly decreases with farm size for subsistence farmers, but not for semisubsistence farmers, implying that pesticide use may be used to ensure sufficient food supply for home consumption. Finally, we find barriers to the use of pesticides for subsistence farmers, both in terms of financial constraints and economies of scale. This finding implies that risk‐mitigation strategies, such as crop insurance, may not target food security concerns of subsistence farmers. Given these different motivations for pesticide use, policymakers may wish to consider effective tools to support rural food security for farmers in the poorer regions of China in order to decrease pesticide use.     

红枫湖沿岸土地利用变化与生态风险评估

本文以喀斯特地区典型高原湖泊-红枫湖为研究对象,依据景观生态学及生态风险评价等相关理论,综合运用“3S”技术、野外调查验证和生态风险评价及格局优化等技术手段,从土地利用变化演变及景观尺度上就红枫湖湖岸周围的生态风险进行探讨,定量分析湖岸周围格局演变及生态风险变化特征,针对性地提出湖岸周围格局优化的调控措施。本文对丰富喀斯特地区高原湖区景观生态格局及风险评价的研究内容、指导红枫湖流域及类似高原湖泊流域的生态环境保护及恢复、促进区域可持续发展具有一定的理论价值和实践意义。     

浅析现行土地利用/覆盖变化描述方法

土地利用/覆盖变化是当前全球变化研究的热点问题之一;将土地利用/覆盖变化的描述方法分为土地利用时空变化和景观格局两个方面,分别从土地利用程度、动态变化速度、位置迁移和转换方向及来源方向等角度分析,对土地利用变化过程中的景观格局指数的变化规律总结归纳,并对指数的适宜性作以分析。     

崇明东部土地利用变化及景观格局分析

本文选择崇明东部为研究区域,利用GIS和RS技术对1988、1997年和2005年卫片和航片进行了提取、分类和分析,并计算了景观格局指数,分析了近20年来土地利用及景观格局变化.结果表明:耕地基本没有变化,河流水体、农村居民点等不断增加,潮滩大大减少,城镇发展缓慢,随着人类活动程度的加剧,景观多样性稍有下降,均匀度上升...     

Key issues of land use in China and implications for policy making

The paper aims to comprehensively analyze key issues of current land use in China. It identifies the major land-use problems when China is undergoing rapid urbanization. Then, the paper interprets and assesses the related land-use policies: requisition-compensation balance of arable land, increasing vs. decreasing balance of urban-rural built land, reserved land system within land requisition, rural land consolidation and economical and intensive land use. The paper finds that current policies are targeting specific problems while being implemented in parallel. There is lacking a framework that incorporates all the policies. The paper finally indicates the current land-use challenges and proposes strategic land-use policy system to guide sustainable land use in the future.     

土地整理与农业可持续发展问题研究

江苏人口众多,土地资源紧缺,经济快速发展过程中土地的非农化速度很快,保护耕地增产粮食,促进农业的可持续发展问题随着人口、经济高速增长而日益受到重视。江苏省开展的土地整理进行农村土地资源的整合,保持耕地总量平衡,完善农业基础设施,有效地提高土地产出,从而促进土地的持续、高效利用,这为江苏省经济持续高速发展的同时,做好耕地、粮食发展战略决策提供科学依据。     

The effect of land use regulations on farmland protection and non‐agricultural land conversions in China

This paper examines the effect of the Prime Farmland Protection Regulation in protecting high quality farmland from urban development and the subsequent effect on non‐farmland conversion in China in the first decade after the Regulation came into effect (1995‐2005). The empirical evaluation is conducted with geo‐referenced panel data for the entire country. Results indicate that the rate of farmland conversion was reduced during 1995‐2000. About two‐fifths of the reduction results from the protection of farmland with high grain productivity. There is no evidence of the effectiveness of the Regulation in protecting farmland during the period 2000–2005, regardless of land quantity or quality. Farmland development was accompanied by a reduction in forests and grasslands during the period from 1995 through to 2005.     

土地利用规划中土地利用空间结构和布局研究进展

土地利用空间结构和布局是土地利用规划工作中的关键所在,是决定土地利用规划是否科学合理的重要步骤;开展土地利用空间结构和布局优化研究有利于促进土地资源利用的集约高效,有利于新一轮的土地利用规划修编的编制和实施;综述了目前我国土地利用空间布局相关理论的研究进展,回顾了土地利用空间布局所采取的主要技术和手段,对我国土地利用空间结构和布局研究进行了展望;研究表明：我国土地利用空间布局理论研究有了长足进展,但还未形成严密的科学理论体系;在研究视角上,多注重耕地和基本农田保护,在“统筹兼顾”“以人为本”“理性发展”等方面应加强;在研究方法上,应加强现代数学模型与计算机空间模拟等方法在土地利用规划布局中的应用研究,加强参与式土地利用规划理论和方法研究,与传统的规划研究方法和手段相结合,形成客观、准确、科学的土地利用规划技术体系。     

Cultivated land productivity potential improvement in land consolidation schemes in Shenyang,China: assessment and policy implications

Cultivated land productivity potential improvement (CLPPI) assessment is the fundamental basis to launch land consolidation, which is one of the most important way to increase the grain productive capacity. Previous studies on CLPPI assessment have focused on factors related to natural conditions of cultivated land, but they ignored the impacts of utilization conditions, including plot characteristics and agricultural infrastructure, which account for substantial CLPPI from land consolidation. Based on the crop-growth model and Agro-ecological Zoning (AEZ) methodology, this paper proposed a modified CLPPI assessment model to estimate the improvement of land productivity potential via land consolidation. Meanwhile, the contribute rates of different factors involved in determining the CLPPI were also analysed to reveal the ideal work focus and policy direction for land consolidation. Results showed that the calculated CLPPI values had obvious spatial variety in Shenyang, of which the average was 326.18. For the consolidation case, total crop production in Shenyang could be increased by as much as 149.89 × 107 kg, 20% of the current yield. CLPPI is the comprehensive outcome of both natural and utilization qualities of land use, and the current productivity potential of cultivated land in Shenyang relied much less on natural conditions such as soil than on utilization conditions such as agricultural infrastructure. In addition, medium-productivity lands were most appropriate target areas for the implication of land consolidation projects. Actually, the arrangement of land consolidation projects should not only consider CLPPI as in the past, but also add the theoretical productivity potential into consideration. Moreover, the realization of estimated CLPPI also calls for active changes of the whole land management system. An integrated institution for the full implementation of land consolidation, proper regulations and laws on the follow-up protection of cultivated land productivity potential, economic policies to stimulate the willingness of farmers, and a transfer mechanism for cultivated land are all needed policy changes.     

Community-based rural residential land consolidation and allocation can help to revitalize hollowed villages in traditional agricultural areas of China: Evidence from Dancheng County,Henan Province

The accelerated rural hollowing driven by vast and increasing out-migration of rural labors under urban–rural dual-track system has imposed huge obstacles on improving land use efficiency and coordinating urban–rural development in China. Taking Dancheng County in Henan Province as an example, this paper analyzes the status quo of rural hollowing and discusses two typical rural residential land consolidation and allocation (RRLCA) practices in traditional agricultural areas (TAAs) of China. The results show that, Dancheng experienced rapid rural hollowing characterized as the hollowing of rural industries, infrastructure, and residential population and settlements. However, Dancheng has considerable potential and the necessity of RRLCA, for the model-based estimation shows that the potential of increasing farmland by carrying out RRLCA was about 5649 ha. The two community-based RRLCA practices show positive effects on the improvement of local living conditions, increment of farmland area and development of rural industries. Their experiences, including self-organized rural planning, democratic decision-making, and endogenous institutional innovation may benefit future RRLCA. Overall, it indicates that promoting community-based RRLCA scientifically according to local conditions could provide an integrated platform for increasing farmland area, developing modern agriculture, promoting new countryside construction, and thus revitalize hollowed villages. On considering the limitations and obstacles of current initiatives, suggestions for future RRLCA in rural China have been put forward.     

基于全过程的土地整治项目实施问题、成因及对策研究

研究目的:分析目前土地整治项目实施中的突出问题,从实施全过程入手探寻土地整治项目实施问题的成因机制并发现控制问题产生的关键环节,提出保障土地整治项目实施高效实施的对策建议。研究方法:调研分析法、文献综述法及定性与定量结合法;研究结果:土地整治项目实施过程主要包括立项、规划、施工、验收4个阶段,目前项目实施中存在规划设计变更大、施工周期超期、工程质量不优、验收进度慢和后期管护不到位等突出问题,研究从不同角度对问题的成因机制进行了分析,并提出可以从项目实施过程对已有问题进行控制,并从项目立项审查要点、规划设计审查体系、从业单位评级制度与准入机制、全业务流程的信息监管平台、经费使用与管理体系和管护机制等方面提出了保障土地整治项目高效实施的对策。研究结论:从土地整治项目实施全过程控制可以有效控制实施中存在的问题,目前亟待构建土地整治项目的高效实施支撑体系以保障土地整治项目的高效实施。     

The roles of risk preferences,selection, and uncertain returns on land contracts

Using panel data on a statistically representative sample of Iowa farmland parcels from 1997 to 2017, we analyze the factors determining whether land is farmed by the owner or rented out under a cash rent or crop share contract. The landowner's decision to rent or operate the land depends on the distribution of expected net returns to the land, and so estimates of the factors affecting rental terms will be biased if the sample only includes rental contracts and excludes the owner-operator. Land with higher mean and/or lower variance of expected net returns is most likely to be rented out. Participants in the rental market will include the most risk-averse landowners and the least risk-averse tenants, while the least risk-averse landowners operate their own land. Our empirical results suggest that the rising use of cash rent contracts and declining incidence of owner-operation and crop-share rental contracts is consistent with falling coefficient of variation in expected net returns per acre.     

我国农药使用现状、原因及对策研究

我国农药使用状况十分不堪,对农村生态环境及广大农民的身体健康造成严重影响,究其根源,农药管理体系不健全,生物农药发展滞后及农民的低物质文化水平是主要原因;要解决此问题,必须从这3方面着手,逐步完善农药管理体系,大力发展生物农药,积极促进农村经济和教育的发展。     

Patterns of revenue distribution in rural residential land consolidation in contemporary China: The perspective of property rights delineation

Rural residential land consolidation (RRLC) in contemporary China refers to activities related to the replanning and reallocation of rural residential land to construct new rural residences, to increase land-use efficiency and to improve rural amenities in the context of rural revitalization. The objective of this study is to elucidate the patterns of revenue distribution in RRLC by addressing the following questions. Given incomplete and ambiguous formal rules in China, how can rural land property rights be delineated to distribute and coordinate interests among stakeholders in RRLC? Furthermore, what are the factors that determine the delineation of rural land property rights to distribute land revenue? A theoretical framework for the delineation of rural land property rights is developed from the perspectives of the institutional environment, governance and resource allocation. A comparative analysis of two typical cases of RRLC in contemporary China is conducted to support the research hypotheses. This study finds that bargaining power is the fundamental determinant of delineating rural land property rights to distribute revenue in RRLC. Furthermore, intergovernmental competition motivates the local government to fully deploy strong bargaining power, while concerns about social stability provide some constraints. A strong capability for collective action reinforces the bargaining power of rural households. This study provides new insights into the delineation of rural land property rights and subsequent revenue distribution based on distinctive institutional settings and RRLC in China, enriching the theoretical and empirical findings in the property rights school. Policy recommendations on revenue sharing of RRLC are proposed accordingly.     

基于马尔柯夫模型的酒泉市肃州区LUCC趋势预测

甘肃省酒泉市近年来经济发展迅速,但生态环境也遭到一定程度的破坏;拟通过对其土地利用和覆盖变化的研究,为环境保护与经济协调发展提供决策支持;依据肃州区1988～2000年土地利用变更调查数据,对该区域LUCC进行分析,确定了土地利用类型的转移概率矩阵,并用马尔柯夫链模型预测了该区LUCC趋势。结果表明,肃州区土地利用将呈现耕地、水域和建设用地增加,林地、草地和未利用土地减少的发展趋势。     

农用地整理对区域景观动态与生态风险影响研究——以福建省建溪流域为例

研究目的:以福建省建溪流域为例,基于2010—2016年的景观类型数据和农用地整理数据,分析农用地整理对区域景观动态和生态风险的影响。研究方法:单一变量法,景观格局指数,生态风险指数。研究结果:(1)2010—2016年间通过农用地整理工程增加的耕地主要在海拔高于300 m的区域;(2)农用地整理工程中的新增耕地主要来源于草地、园地和林地,也有部分城镇村及工矿用地、交通用地等由于村庄合并或矿区土地复垦等原因被整理为耕地;(3)每一种农用地整理工程类型都是一种风险源,其释放的风险压力主要有景观单一化和景观破碎化两种;(4)2010—2016年建溪流域的生态风险值介于2 386.11～2 394.76,2010年后生态风险指数逐年降低。研究结论:本文对大尺度上关于农用地整理对景观生态的影响研究有借鉴意义,可以为区域尺度的土地利用优化设计和农用地整理设计规划提供科学依据。     

大庆市土地利用变化对生态环境的影响

随着人口增长和石油产量的逐年降低,大庆市对土地利用模式的改变及对土地利用强度的加大,导致土地退化,土壤污染,水污染加重和生物多样性降低等后果;对土地利用变化的生态环境效应的研究,可以改善生产条件,促进区域可持续发展。     

保护和提高耕地综合生产能力的新思考一江苏省土地开发整理复垦调研报告

耕地问题事关粮食安全和社会主义建设大局 ,随着农业结构调整和农村城镇化进程的加快 ,耕地保护形势日益严峻。文章通过对江苏省六市县土地利用状况的调查发现了目前土地开发整理及复垦面临的困境与存在的八个主要问题 ,为解决这些问题 ,文章提出了七项对策建议。     

"3S"技术在土地可持续利用决策中的应用

土地的可持续利用是整个社会经济发展的根本基础,利用信息技术加强对土地资源的管理规划是未来的发展趋势;“3S”技术是全球定位系统、遥感、地理信息系统和专家系统的简称;对“3S”技术作了简要介绍,并从其技术方面分析了“3S”技术在土地利用和保护领域的作用和应用。