村镇退化废弃地遥感监测方法初探

研究目的：开展村镇退化废弃地遥感监测技术分析,为村镇退化废弃地遥感快速监测奠定技术基础。研究方法：选择甘肃省白银市平川区作为研究区域,设计研究区内典型村镇退化废弃地类型,建立不同类型村镇退化废弃地的高分辨率遥感影像特征,提出利用遥感手段快速监测村镇退化废弃地的技术流程,详细描述了其技术方法,进而阐述村镇退化废弃地快速监测移动作业平台的详细功能需求。研究结果：研究区典型村镇退化废弃地在退化废弃前后的遥感影像特征和实地特征均有显著差别,本文的技术流程和方法可以服务于村镇退化废弃地的快速遥感监测。研究结论：采用遥感手段监测村镇退化废弃地在技术上是可行的。     

街区经济发展中土地集约利用评价研究——以西安市莲湖区为例

研究目的:以街区经济为平台,定量评价研究区内街区土地集约利用整体状况,以期为其他区域发展街区经济、合理利用土地提供参考。研究方法:地理信息系统(GIS)技术和方法,多因素综合评价法,聚类分析法。研究结果:选择的西安市莲湖区38个街区中,土地集约利用存在一定的差异,较好集约利用3个,一般集约利用24个,低度利用11个,因此在发展街区经济时,应采取提高区域整体经济水平、提高商业用地在整个街区中所占的比例和提高街区商业用地的容积率等措施来提高土地集约利用水平。研究结论:西安市莲湖区街区经济土地集约利用仍有较大潜力。     

土地管理视角下的法定地役权研究

研究目的:证明法定地役权独立存在的必要性,并对其设定条件和适用范围进行研究。研究方法:采用文献研究、比较研究和理论联系实际的方法,对法定地役权存在的基础、基本功能、存在形态及其与相邻权的关系进行了研究。研究结果:(1)法定地役权的存在有其客观必要性,难以用相邻权代替之;(2)用相邻权制度调整土地利用中的地役关系,具有较大的局限性;(3)用法定地役权制度调整地役关系,更符合土地利用实践发展的客观要求。研究结论:法定地役权应成为我国地役权制度的重要内容,建议进一步完善中国的地役权制度。     

Rural-urban gradient analysis of ecosystem services supply and demand dynamics

Urban regions are important places of ecosystem service demands and, at the same time, are the primary source of global environmental impacts. Although there is broad agreement on the importance of incorporating the concept of ecosystem services into policy strategies and decision-making, the lack of a standardized approach to quantifying ecosystem services at the landscape scale has hindered progress in this direction. Moreover, tradeoffs between ecosystem services and the supply/demand ratio of ecosystem services in urban landscapes have rarely been investigated. In our paper, we present a method to quantify and map the supply and demand of three essential provisioning services - energy, food, and water - along the rural-urban gradient of the eastern German region Leipzig-Halle. This urban region has experienced significant socio-economic dynamics and land use changes since the German reunification in 1990. The results show that both the demand and the supply of ecosystem services changed considerably during the time span under consideration (1990-2007). We identified an increasing supply/demand ratio of food and water but a decreasing supply/demand ratio of energy. In addition, the pattern of ecosystem demands shows a levelling of rural-urban gradients, reflecting profound modifications of traditional rural-urban relationships. The changes of ecosystem service supply gradients are determined more by land use intensity, such as the intensification of agricultural production, than by land cover changes such as urban sprawl. The comparison of supply/demand ratios and rural-urban patterns of ecosystem services can help decision-makers in landscape management in striving for a sustainable balance between resource supply and demand.     

我国土地整理生态环境评价研究综述

改善土地利用的生态环境是土地整理的重要内容和目标。针对土地整理生态环境评价,国内很多学者从不同领域、学科视角开展了大量理论与实证研究,取得了丰硕的成果。本文主要从土地整理生态环境评价的理论研究、指标体系和评价方法研究等方面对近年来我国土地整理生态环境评价研究进行了梳理和总结,并针对目前存在的问题进行了思考和展望,以期为科学推进我国土地整理乃至农村土地整治工作提供借鉴。     

基于GIS的典型白浆土区八五三农场耕地地力的定量评价

以黑龙江省典型白浆土区的853农场为例,采集农田耕层(0~20cm)样品1695个,以土地利用现状图的耕地图斑为评价单元,选取10个指标,利用特尔菲法和层次分析法,结合GIS技术,对853农场耕地地力进行了定量化的分析和评价。评价结果表明八五三农场耕地地力整体水平为:三级地占总耕地面积的35.47%,其次为二级和四级,分别占27.53%和20.86%,比例最小的是一级和五级地,分别占6.83%和9.30%。分级结果较好的体现了地区特点,同时明确了不同等级耕地的面积、空间分布格局,为探讨制定科学的培肥政策、提高作物产量和土壤基础地力,保护生态环境提供了定量化的分析依据。     

Status and financial performance of organic vegetable farming in northeast Thailand

In line with the national sustainable agriculture development policy of the Government of Thailand, organic vegetable farming (OVF) promotion projects have been implemented in several provinces of the country. Based on data collected through a questionnaire survey of 172 sample vegetable farmers in Mahasarakham Province of northeast Thailand, this study firstly assessed the status of OVF and then, analyzed the financial performance of three main vegetables cultivated, namely: morning glory, green onion and Chinese kale. Finally, sensitivity analyses of the financial performances for all three vegetables were conducted under four assumed scenarios with respect to price of synthetic fertilizers and pesticides, and yield and price of organic vegetables. The findings of the analysis on the status of OVF revealed that organic vegetable farms accounted for very small percentage of the total area used for all vegetables in the study area. Results of the financial analysis also showed that OVF was much less financially attractive than conventional vegetable farming due to low yield which usually does not come with premium price of the vegetables. Still farmers are growing organic vegetables on small scale primarily for household consumption. The findings of the sensitivity analyses indicated that the removal of direct or indirect subsidies for synthetic fertilizers and pesticides, and appreciation in the yield and price of organic vegetables can enhance the financial performance of OVF. In view of the possible rejection of radical policies that encourage OVF by discouraging conventional vegetable farming, this study suggests appropriate policy measures that could directly provide incentives for organic vegetable production and consumption.     

基于信号博弈的土地使用权出让中围标“蜜罐”行为的分析

研究目的:依据土地使用权招标出让活动的特征,构建围标"蜜罐"行为的动态贝叶斯博弈模型,找出促使均衡结果合理化的因素变化差异和关系。研究方法:信号博弈。研究结果:(1)由分开均衡的求解可知,在土地使用权招标中,当招标人看到投标人报低价时将检查,看到投标人报高价时则不检查;投标人围标时将选择报低价,不围标时将报高价。(2)由合并均衡求解可知,无论投标人围标与否,投标人报低价时,此博弈有两个完美贝叶斯均衡。研究结论:为遏止投标人进行围标合谋这一"吃蜜罐"的行为,要增加围标成本、合理控制检查成本、降低投标人预期收益和完善惩罚形式、加大惩罚力度。     

农地整治综合效应诊断指标体系及方法

研究目的:构建能较客观地反映和表征农地整治效应的指标体系,并采用相关效应诊断模型定量衡量农地整治对区域经济、社会、环境所产生的影响,为整治项目的规划设计和土地整治专项规划提供支持。研究方法:理论分析法,专家咨询法,层次分析法,综合指数法。研究结果:将农地整治的综合效应分为资源经济效应、社会效应、环境效应和景观效应,分别从这4个方面构建诊断指标;效应的表达用农地整治前后诊断指标值的差异表示,这种表达方式既能体现效应的变化方向,又能表示出效应的强度。研究结论:案例区的实证表明,农地整治效应的诊断指标体系具有可操作性和科学性,效应评估的方法可行。     

建立适应土地资源市场配置的国家宏观调控体系

研究目的:构建适应市场配置的国家宏观调控体系,保障土地资源市场配置的顺利实施。研究方法:系统分析法,政策分析法。研究结果:在市场配置下,政府可以通过以下措施实现对土地市场的宏观调控:(1)改革现行土地利用规划、计划制度,建立适应市场经济的规划、计划体系;(2)改革并建立能够促进土地集约利用、优化配置、收益公平分配的土地财税制度;(3)实行土地用途管制分区,限制土地使用权,克服土地利用的负外部性;(4)为实现公共利益征收土地所有权、使用权,由国家确定其土地用途;(5)改革现行行政审批制度,简政放权;(6)尽快制定《土地基本法》。研究结论:目前应首先改革财税制度,把建立稳定的、与地方政府事权相匹配的地税体系作为土地管理制度改革的切入口,为全面开展土地管理制度改革奠定基础。