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1.
The Brazilian Cerrado, a biodiverse savanna ecoregion covering 1.8 million km2 south and east of the Amazon rainforest, is in rapid decline because of the expansion of modern agriculture. Previous studies of Cerrado land-use and land-cover (LULC) change imply spatial homogeneity, report widely varying rates of land conversion, use ambiguous LULC categories, and generally do not attempt to validate results. This study addresses this gap in the literature by analyzing moderate-resolution, multi-spectral satellite remote sensing data from 1986 to 2002 in two regions with identical underlying drivers. Unsupervised classification by the ISODATA algorithm indicates that Cerrado was converted to agro-pastoral land covers in 31% (3646 km2) of the study region in western Bahia and 24% (3011 km2) of the eastern Mato Grosso study region, while nearly 40% (4688 km2 and 5217 km2, respectively) of each study region remained unchanged. Although aggregate land change is similar, large and contiguous fragments persist in western Bahia, while smaller fragments remain in eastern Mato Grosso. These findings are considered in the current context of Cerrado land-use policy, which is dominated by the conservation set-aside and command-control policy models. The spatial characteristics of Cerrado remnants create considerable obstacles to implement the models; an alternative approach, informed by countryside biogeography, may encourage collaboration between state officials and farmer-landowners toward conservation land-use policies.  相似文献   

2.
基于政府与市场关系,运用产权理论与新结构经济学理论,探讨农村土地要素市场化的政策史流变、经济学意涵和制度性创新。研究表明,第一,改革开放以来市场在土地资源配置中的作用经历了由辅助性到基础性再到决定性的历史转变,农村土地要素市场化也经历了改革探索期、改革发展期与改革深化期。第二,土地要素市场化的经济学本质是土地转让权的赋予,赋予农户充分、完整且有保障的土地转让权具有理论必要性和现实必然性。第三,未来的农村土地要素市场化改革,一方面要培育有效市场,以土地产权制度改革为主线,做好产权界定、产权配置和产权保护工作;另一方面要建设有为政府,以土地管理制度改革为依托,做好数量管控、用途管制和市场监管工作。  相似文献   

3.
This article explores the issues that arise when land use management organizations change their previous ways of relating to the public. I introduce an analytic framework for evaluating organizational changes that are grounded in participatory planning and decision making. Using a case study of a recent planning initiative of the Wisconsin Department of Natural Resources, I examine dynamics of trust, civic capacities, personal demands, history of working relationships, and interest in the issue at hand. Though preliminary, the conclusions drawn from this research illustrate how these dynamics may influence the success of participatory planning that reflects organizational change.  相似文献   

4.
基于CA-Markov模型的大连市旅顺区土地利用变化及预测研究   总被引:1,自引:0,他引:1  
实时监测土地利用及其变化(LUCC)的状况对于经济增长、社会进步、环境保护以及生态文明建设具有重要的意义。本文基于IDRISI软件中的CA-Markov模型,分析了大连市旅顺区1994年-2014年的土地利用变化,同时预测了2024年的土地利用状况。结果表明:旅顺自1994年来,建筑用地面积逐年增加,并主要集中在中南部和西部沿海地区,与此同时,耕地面积也逐年增加,但由原来的西部逐渐演退至北部区域的丘陵地带,林地面积逐步萎缩,面积大幅下降,其主要被开垦为耕地或建筑用地,在本区域中南、西南部,林地大多直接转变为建筑用地或先转变为耕地再转变为建筑用地,而北部则主要转变成了耕地和相对较小的居民点,水域(湖泊、河流)的面积逐年减少,湖泊、水库面积萎缩,随着城镇化的加快和人口数量的不断增加;由于不断地城市用地开发和林地的砍伐以及耕地的弃用等综合因素导致,未利用地减少。总体上,旅顺的土地利用变化由于经济建设的力度不断加大,人工自然景观用地越来越多,生态安全压力不断增大,未来十年间,旅顺土地利用将持续20年来的趋势,但变化速度放缓。  相似文献   

5.
In the north rim of the Mediterranean region, where forest cover is increasing as a result of land abandonment and temperatures are rising as a result of climate change, there is increasing interest for the effects of such changes on the runoff of water courses. This is a paramount issue for the conservation of many freshwater habitats and species. In this work we studied the effects of both an increase in forest cover after depopulation and land abandonment and an increase in temperature on the runoff of a Mediterranean catchment and on the aquatic and semi-aquatic fauna species of the stream (Olzinelles valley, NE Spain). Although in our simulation no decreasing trend in runoff is detected, the monthly runoff-rainfall ratio is now 15% lower than 30 years ago, a fact that may be attributed to a drier period rather than to the small afforestation experienced by the catchment in the last decades. Other factors such as increasing temperatures, changing rainfall patterns and increasing canopy cover are discussed. The observed decrease in the water flow has caused the disappearance of white-clawed crayfish (Austropotamobius pallipes), Mediterranean barbel (Barbus meridionalis), chub (Squalius cephalus), European eel (Anguilla anguilla), and southern water vole (Arvicola sapidus). Our results suggest that in a progressively warmer climate, and especially after land abandonment processes, management of Mediterranean mountain areas should be oriented towards an appropriate distribution of agrarian and forest land-covers in terms of water availability. Down to the stream scale, the pools that keep water throughout the year should be conserved and extended to enhance its potential to maintain aquatic and semi-aquatic species populations.  相似文献   

6.
随着我国经济的高速发展和城市化进程的加快,农地非农化已是一个不可扭转的趋势,尤其是在城乡结合部。在农用地转征用过程中,如何保护农民的利益不受侵犯也成为了当今学术界的一个热门话题。本文从土地征用制度的改革方向以及集体土地产权制度变迁的趋势来讨论如何进一步保护和完善失地农民原有土地承包权的问题。试图通过对土地征用制度改革的反映而进一步完善集体土地产权制度提出一些政策建议。  相似文献   

7.
在我国城镇化进程中,保障土地生态安全是其重中之重。就我国目前的社会阶段来看,人民自身素养和科学技术积累程度还没有达到土地私有化的水平,目前个体农民并没有这个能力,一旦土地私有,就会出现土地过分开发的情况,土壤养分会在短期内被榨干,土地修复复垦是一个需要大量人力物力科学技术的工程,个体农民及农民集体根本没有这个能力,就会造成土地荒废遗弃,甚至加重荒漠化、沙漠化。所以土地私有制并不适合我国现阶段的社会发展。以资源代际公平、土地生态安全的角度来看,土地国有是适应现阶段社会发展要求的。土地的利用与开发需要养护和维持,以达到后代子孙的持续发展。  相似文献   

8.
This work compares the effects of neoliberal and post-neoliberal land-use policies on forest cover along the Corredor Bioceánico of southeastern Bolivia to determine if rates of agriculturally driven forest clearance have changed since the Morales’ administration came to office in 2005. Satellite image analysis, supported by semi-structured interviews with farmers and representatives of key institutions, shows that deforestation for commercial agriculture in Santa Cruz continues and has increased in certain “hotspots”. Previous research has shown that the environmental effects of neoliberalism on forest cover are varied, but more broadly, reduced state intervention has meant less environmental regulation and greater deforestation, while strong government is better able to curtail deforestation. Although neoliberal policies triggered an unprecedented level of forest clearing in Bolivia, rates have generally continued to increase and can be indirectly linked to the administration's new agrarian reform and pro-environmental regulations. This trend is counterintuitive and stems from unanticipated responses such as deforestation through fire to prove productive use under the reform's socio-economic function requirements. Given increased regulation and enforcement of forest clearing and burning under Morales, in contrast to the neoliberal era, our analyses suggest that rates will continue to increase under the current political climate, which has further polarized the opposition in Santa Cruz.  相似文献   

9.
Over the past decades, urban sprawl and agricultural intensification have enormously changed the traditional cultural landscape of the Swiss lowlands. This research aims to analyze the driving forces of urbanization, agricultural intensification, and greening in five municipalities of the periurban Limmat Valley, near Zurich, Switzerland. The main objectives of the paper are (1) to quantify the change in urbanization, agricultural intensification, and greening, (2) to determine the driving forces of landscape change, (3) to determine the relative importance of socioeconomic, political, cultural, technological, and natural/spatial driving forces, and (4) to establish from which administrative levels and spatial scales the most important driving forces originate. Changes for the periods 1930–1956, 1957–1976, and 1977–2000 are documented based on a comparison of cartographic maps. A list of 73 potentially relevant driving forces is established based on document analysis. Based on further document analysis and expert interviews, 52 of them were found to be relevant primary driving forces for the documented landscape changes. We found that in all three periods, urbanization was the most important process of change. Greening is steadily increasing in importance and surpassed agricultural intensification in the last period. Overall, as well as for urbanization, the economic driving forces, followed by political driving forces, are most important for landscape changes in all three periods. Cantonal driving forces are most important, followed by the national, local and international driving forces. By presenting an approach to quantify the contribution of major driving forces groups to landscape change this study contributes to method development in land change research.  相似文献   

10.
以河南省为研究区,对不同年份的土地利用数据进行分类系统整合,在此基础上,对河南省1996~2009年土地利用类型进行了对比分析,分析得出耕地、城镇村及工矿用地、林地、交通运输用地面积在增加,园地、草地、水域及水利设施用地、其它土地面积在减少,在各类土地类型转换中,林地是变化最为激烈的土地利用类型,其次是其它土地,变化最稳定的地类是交通运输用地,其次是耕地。  相似文献   

11.
目前土地利用和管理的政策重点为:调结构、调过剩产能、完善城乡统筹中土地制度,严格保护耕地.针对资源供应的刚性影响逐步扩大,全社会的发展理念发生着深刻的变化,为提高资源利用效率、走节约集约道路提供了良好的外部环境.应该供需双向调节,加速结构调整、统筹城乡发展,促进城市转型,加快宜居城市建设、实施建立差别化供地政策、强化耕地建设性保护专项工作.对2011年来讲,促进经济发展方式转变,节约集约用地是关键,严格保护耕地是硬任务,应推动土地利用方式根本转变.促进经济发展方式转变和经济社会又好又快发展.  相似文献   

12.
Forest Transition Theory (FTT) suggests that reforestation may follow deforestation as a result of and interplay between changing social, economic and ecological conditions. We develop a simplistic but empirically data driven land use transition agent-based modeling platform, interactive land use transition agent-based model (ILUTABM), that is able to reproduce the observed land use patterns and link the forest transition to parcel-level heuristic-based land use decisions and ecosystem service (ES). The ILUTABM endogenously links landowners’ land use decisions with ecosystem services (ES) provided by the lands by treating both lands and landowners as interacting agents. The ILUTABM simulates both the land use changes resulting from farmers’ decision behaviors as well as the recursive effects of changing land uses on farmers’ decision behaviors. The ILUTABM is calibrated and validated at 30 m × 30 m spatial resolution using National Land Cover Data (NLCD) 1992, 2001 and 2006 across the western Missisquoi watershed, which is located in the north-eastern US with an estimated area of 283 square kilometers and 312 farmers farming on 16% of the total Missisquoi watershed area. This study hypothesizes that farmers’ land use decisions are made primarily based on their summed expected utilities and that impacts of exogenous socio-economic factors, such as natural disasters, public policies and institutional/social reforms, on farmers’ expected utilities can significantly influence the land use transitions between agricultural and forested lands. Monte Carlo experiments under six various socio-economic conditions combined with different ES valuation schemes are used to assess the sensitivities of the ILUTABM. Goodness-of-fit measures confirm that the ILUTABM is able to reproduce 62% of the observed land use transitions. However, the spatial patterns of the observed land used transitions are more clustered than the simulated counterparts. We find that, when farmers value food provisioning Ecosystem Services (ES) more than other ES (e.g., soil and water regulation), deforestation is observed. However, when farmers value less food provisioning than other ES or they value food provisioning and other ES equally, the forest transition is observed. The ILUTABM advances the Forest Transition Theory (FTT) framework by endogenizing the interactions of socio-ecological feedbacks and socio-economic factors in a generalizable model that can be calibrated with empirical data.  相似文献   

13.
WTO negotiations, as well as problems associated with intensive agriculture, such as overproduction, dependency on high levels of subsidies, diffuse pollution, soil degradation and loss of wildlife, have led to a reconsideration of agricultural policies in Europe. In April 2005, the new common agricultural policy (CAP)-reform came into force in the United Kingdom, decoupling financial support to farmers from agricultural production. Farm income support payments are now linked to compliance with standards (cross-compliance rules) which protect the environment, animal health and welfare. In the light of these policy changes, semi-structured interviews were carried out with 36 farmers in five catchments in the UK to explore interrelationships between CAP-reform, agricultural land management and runoff-related problems. Results from three catchments are specifically highlighted because of their relevance for soil policy.The CAP-reform appears to facilitate and accelerate changes in the agricultural sector that were already happening. It is likely that upland livestock farms will extensify further, which will reduce environmental burdens such as diffuse pollution, soil compaction and runoff. The uptake of agri-environment schemes by individual farmers has increased since the CAP-reform. However, additional impacts are limited as there is a tendency among participants to enter these schemes based on existing features and practices.Although most farmers interviewed for this study appear to recognise the need to reduce soil erosion and diffuse pollution, they are less convinced they should be held responsible for controlling storm-water runoff from farmland that might contribute to flooding downstream. However, there are opportunities to achieve several objectives simultaneously, including improved soil management, runoff control and reduced pollution. Lessons can be learned from farmers’ opinions about CAP-reform, from successful interventions that aimed to reduce soil erosion and diffuse pollution, and also from failures. Recommendations are made for improvements to the current agri-environment schemes and to promote land management practices with less environmental burden.  相似文献   

14.
我国《土地管理法》成长历程及修改完善   总被引:1,自引:0,他引:1  
在改革开放和社会主义市场经济体制逐步确立的大背景下,我国的《土地管理法》于1986年颁布实施,并在1988年和1998年进行了两次修改。对《土地管理法》的几次重要修订使我国的土地管理步入了市场化轨道、加强了耕地保护、启动了保护农民权益的改革。但《土地管理法》在土地利用总体规划、耕地保护、土地产权制度、土地征用等方面仍存在着问题,应进一步修改完善。要从土地利用总体规划法律制度建设、建立耕地保护新机制、进一步完善土地产权制度、完善征地制度等方面对现行《土地管理法》进行改革。  相似文献   

15.
The negative impact of anthropogenic activity on tropical forests is well documented, but the underlying factors, including socioeconomic conditions, government policy, and agricultural practices, that influence forest degradation in developing countries are poorly understood. For centuries, Soppinabetta forests (SBFs) in the Western Ghats of India have provided essential habitat for wildlife and vital organic resources (leaf litter, green foliage) for the cultivation of betel nut palms (Areca catechu) and rice paddy (Oryza sativa). Historically, betel nut farmers carefully managed resource extraction in SBFs, but recent changes in land use policy allow for unmitigated resource extraction by site dwellers, which may imperil the traditional sustainable management of SBFs. Site dwellers live on government allotted sites and primarily derive their income through the sale of forest-based products. We used SBFs as a model system to investigate the factors governing: (i) forest resource extraction, (ii) the effect of changing agricultural practices on the rate of resource extraction, and (iii) farmers’ perception of SBFs conservation in response to changes in governmental land use policy. Results from surveys of 90 households (57 farmers and 33 site-dwellers) and the forest department indicate individual farmers collected an average of 31.09 (range 0-125) metric tons of leaf litter and 19.11 metric tons (range 0-120) of green foliage per year. Organic resource harvesting by farmers was positively correlated with the size of betel nut plantations, size of SBFs, and number of livestock owned per household. Betel nut plantations require six times more compost than food grains cultivated in field paddies. In past one decade, 33% of field paddies have been converted into betel nut plantations, increasing the strain on SBFs for forest resources. Farmers believe that when they lose provisional ownership of SBFs, site dwellers unsustainably harvest resources and severely damage SBFs. We suggest that an inclusive, local-level, farmer-driven protection be implemented to preserve the SBF heritage system of Western Ghats.  相似文献   

16.
本文在分析广东省土地登记现状的基础上,对当前土地登记制度建设中存在的问题进行了深入探讨,并就此提出一些建议。  相似文献   

17.
本文提出了建立基于B/S模式的土地交易管理系统的优势,阐述了系统的设计和实现方法;较为详细的介绍了系统的构架、功能结构、数据库建设以及系统特点。  相似文献   

18.
基于社会燃烧理论的中国土地储备制度产生与发展研究   总被引:9,自引:0,他引:9  
研究目的 :确定土地储备制度在城市土地使用制度历史演进中的地位 ,对其产生的必然依据和发展趋势进行研究。研究方法 :社会物理学的社会燃烧理论。研究结果 :土地储备制度是城市土地使用制度的第二次革命。研究结论 :社会燃烧理论可引入到制度变迁领域 ,是研究土地储备制度的产生与发展的一个有效的理论工具。  相似文献   

19.
选择环首都经济圈为研究对象,基于土地生产率、土地利用程度、土地投入强度和土地集约效率四个子系统选取构建经济评价指标体系,借助SPSS软件,采用因子分析法分别计算了土地生产率、土地利用程度、土地投入强度和土地集约效率。根据评价结果,从四个方面分别阐述土地经济评价的区域差异及原因,以期能更好的为区域土地资源可持续利用提供参考。  相似文献   

20.
不同于一般的农地制度创新,沿海农村的土地制度变迁属于集体经营性建设用地的范畴,其核心是土地开发权的界定问题。乡村工业化既推动了土地开发权从国家向集体转移,也影响了这一权利的配置方向。本文研究发现,不同乡村工业化模式形塑出不同的土地制度,珠三角的外资充裕型、苏南的外资竞争型、浙江的内生资本稀缺型工业化模式,分别产生了保护股民利益的土地共有制,强调政府统筹能力的土地集体所有制与有利内生资本积累的"公有私占"的土地制度类型,三者都在一定程度上推动了区域性工业生产要素的优化配置。这表明,评价土地制度的绩效,必须着重考虑具体的工业化模式。当前,中国正处于全球资本竞争与产业升级的重要时期,仍然需要发挥土地集体所有制统筹土地开发权的优势,为建立服务于工业发展的高水平公共服务体系提供保障,同时,也应当加强土地的再分配功能,保护农民共享经济发展成果的权利,提高土地集体所有制的制度合法性。  相似文献   

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