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61.
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   
62.
[目的]通过揭示退耕还林(草)工程背景下陕北地区近25年生态系统服务价值的演变规律,旨在为陕北地区的土地利用规划及新一轮退耕还林(草)政策的推进提供参考。[方法]以生态环境脆弱的陕北地区为研究对象,基于1990年、2000年、2015年3期的土地利用变化数据,以退耕还林(草)政策的实施为节点,利用土地转移矩阵、景观格局指数、生态服务价值损益表等方法对陕北地区的土地利用情况、景观格局演变以及生态服务价值的变化进行分析,借助相关性系数对土地利用类型、景观格局及生态服务价值之间的关系进行了定量研究。[结果](1)草地、耕地和林地是陕北地区最主要的土地利用类型,耕地面积减少,林草地面积持续增加且增速加快。(2)近25年,陕北地区景观格局的连接性和通达性降低,景观格局主要呈破碎化发展趋势。研究区各景观类型的破碎化程度增大,空间异质性增加,草地是该地区的优势景观类型。(3)陕北地区1990年、2000年和2015年各类生态系统提供的总生态服务价值分别为38919亿元、39431亿元和40622亿元,退耕还林(草)前年均增长率为1396%,退耕还林(草)后这一比率增加至5622%。[结论]受退耕还林(草)政策的影响,陕北地区土地利用类型和土地景观格局的变化均对生态系统服务价值有显著的影响,但是不同的景观指数对生态系统服务价值的影响程度和趋势不同,水域和林草地面积对生态系统服务价值呈正相关,未利用地和城乡建设用地面积对生态系统服务价值呈负相关。  相似文献   
63.
Aside from the very high inequality of land ownership, South Africa is characterised by a dual land tenure system comprising of private ownership and communal land ownership. Using waves 4 and 5 of the National Income Dynamics Study longitudinal data set, a set of econometric methodologies is employed to quantify the impact of ownership and tenure on an index of subjective wellbeing (SWB) constructed from eight self-reported responses covering general life satisfaction, contrast, social capital, mental health and hope for future. Controlling for the income effect and other pertinent drivers of SWB, the study highlights the non-income impact of land ownership and tenure on the subjective wellbeing of individuals. To account for possible endogeneity and self-selection, instrumental variable and matching method-based treatment effects are computed. This paper has two main findings in relation to land tenure in South Africa: (a) land owners have on average a higher index of SWB compared to those not owning land, and (b) owning land privately, compared to owning land communally, has a positive impact on subjective wellbeing within land owners. These results are consistent and statistically significant across the various estimation strategies and provide additional motivation for expediting land reforms in South Africa.  相似文献   
64.
Over the last two decades, extensive literature has examined the socioeconomic and environmental impacts of China's Sloping Land Conversion Program (SLCP), a program that was launched in late 1990s to mitigate the environmental effects of agricultural production and reduce rural poverty. However, little empirical evidence exists with regard to the impact of SLCP on rural households' sensitivity to nature-induced changes and environmental challenges. In this study, household-level data covering the period 1995–2010 from five Chinese provinces were used to examine the effect of SLCP on farmers' sensitivity to climate change. The empirical results show that participation in SLCP significantly reduced farmers' sensitivity to climate change by reducing their dependency on land and natural resources for income, and by diversifying their livelihood options. Spatially, the results reveal that the effect of SLCP on farmers' sensitivity vary across regions. Specifically, SLCP was found to have a ‘rate effect’ on farmers in the Northern regions and a ‘level effect’ on farmers in the Southern regions. Likewise, we found that the effect of SLCP differs considerably across income groups, with the effect on low- and middle-income groups being most significant. The results indicate that subsidy is the main pathway through which SLCP reduces farmers' sensitivity to climate change. In contrast, we found inclusive evidence about the indirect effect of SLCP farmers' sensitivity through the promotion of non-agricultural employment. These results carry major implications with regard to the effectiveness of ecological conservation programs and their mitigation potential through building farmers' resilience in China and ecologically fragile environments.  相似文献   
65.
A vast array of trends and innovations, such as drones and person-to-person trust solutions, have been proposed to revolutionize the task of recording land and property rights. There is, however, a gap in current research regarding how to approach systematically the future(s) of cadastral systems. This paper introduces socio-technical transitions theory and multi-level perspective (MLP) framework in particular as a way to structure potential pathways for cadastral systems. The approach emphasizes the role of institutional rules of the game – the regulative, normative and cognitive institutional elements – in socio-technical transition processes. Using the Finnish cadastral system as a case study, we illustrate the approach by forming three alternative transition pathways: (1) a cadastral system under digital transformation, (2) differentiating urban and rural cadastral systems, and (3) a cadastral system facing new data management challenges. After describing each transition pathway with a narrative storyline, we reflect them in light of previous discourses of the cadastral domain. Thereby, the study provides new insights into discussions about the future of cadastral systems and land administration in general.  相似文献   
66.
This paper focuses on the estimation of direct damages caused by three flood scenarios with different return periods in the section Făgetul de Sus – Ghimeş – Palanca Pass of Trotuș River, with the aim of highlighting the need of improved land use plans. The damage for three land use classes (residential building, infrastructure and agriculture) were estimated using the damage curves developed by the European Joint Research Centre (JRC) as well as site specific maximum damage values. The data were processed with the help of the ArcMap 10.2 software and FloodRisk tool from QGIS software. Furthermore, the flood risk was assessed using the damage – probability curves, which associates the damage with the corresponding frequency of occurrence. This method was identified and adapted to the characteristics of the study area in order to develop a methodology of flood risk assessment that is answering the question: does the lack of land use plans increase the vulnerability and the flood damage? The results showed that the greatest damages are registered for the residential building land use class for a flood probability of 0.001. In this case the damages reach up to 60% on the scale range of deterioration factor, the total damage value being 2 million euros. For the same hazard probability the total registered damage value for roads is 7500 euro, for railways is around 12,000 euro, while for agriculture is around 84,000 euro. These results highlight the need of protection measures and land use plans development and implementation. Regarding the protection measures we consider that the egalitarianism would be the concept that should be applied in the study area and also an improved cooperation between government, specialized agencies and local authorities at local level would lead to a more efficient flood risk management process. The proposed methodology can be applied for micro-scale analysis, providing quantitative results regarding the flood damage and flood risk assessment. It includes a detailed vulnerability analysis of the elements-at-risk with the aim of developing a more comprehensive approach of flood risk assessment.  相似文献   
67.
In the late 1990s, China aimed to mitigate environmental degradation from agricultural production activities by introducing the world's largest “Payments for Environmental Services? program: the Sloping Land Conversion Program (SLCP). We develop a microeconomic Agricultural Household Model, which can model the production, consumption, and nonfarm labor supply decisions of agricultural households in rural China in a theoretically consistent fashion. Based on this theoretical model, we derive an empirical specification, which we econometrically estimate using the Hausman–Taylor method and a large longitudinal farm household data set. The empirical results significantly differ between regions, but are generally consistent with the results of our theoretical comparative static analysis, for example, that the SLCP significantly decreases agricultural production. While the SLCP only increases nonfarm labor supply and total consumption in some regions, these effects could not be observed in others. The recent reduction of the SLCP compensation payment rates generally had negligible effects on agricultural production and off‐farm work and only very small effects on household consumption.  相似文献   
68.
In recent decades the intensification of agricultural production in many European countries has been one of the key components of land-use change. The impact of agricultural intensification varies according to national and local contexts and a greater understanding of the drivers of intensification will help to mitigate against its negative impacts and harness potential benefits. This paper analyses changes in land use intensity in six case studies in Europe. A total of 437 landowners were interviewed and their responses were analysed in relation to changes in land use intensity and agricultural production between 2001 and 2011. In the case studies in Western and Eastern Europe we observed stabilisation during the last decade, and no clear tendency of increase or decrease of land use intensity. The use of fertilizers and pesticides seems to have decreased in our cases in Western Europe, which is contrary to trends in Eastern Europe. Agricultural production remained stable in almost all cases, except for an increase in Austria and Romania which may indicate that the farming efficiency has increased. A statistical analysis showed a division between study areas in Romania and Austria (increasing land use intensity) versus those in the Netherlands, Denmark and Greece (decreasing). In the Mediterranean cases we observe a process where agriculture is becoming increasingly marginalised, at the same time as changes in function with regard to urbanisation and recreational land uses have taken place. Logistic regression highlighted the importance of farm size and farmer type in understanding changes in land use intensity. The dominant pattern of stabilisation which has occurred over the past 10 years may also partly be a result of effective EU and national environmental and agricultural policies, which are increasingly concerned with improving environmental conditions in rural areas.  相似文献   
69.
70.
The German government has committed to substantially limiting future land consumption. Among the most prominently discussed policy instruments is the implementation of a cap & trade system for land consumption, in which a limited amount of certificates is allocated to and traded by municipalities. Since these certificates would be a prerequisite for conducting building projects, this system is expected to reduce urban sprawl and foster the efficient allocation of land consumption projects. While previous empirical studies have supported these projections, the potential fragility of a cap & trade system in the case of macroeconomic shocks has not been considered. In three laboratory experiments, we simulate the impact of economic and budgetary crises within a cap & trade scheme for land consumption. We find that a market-based system succeeds in compensating macroeconomic disturbances with only minor welfare losses. Certificate prices in auctions and trading are somewhat more volatile before shocks, yet normalize afterwards. Trading volumes and the specifics of project realizations remain largely unaffected. Unrelated to the macroeconomic shocks, auction and market prices persistently diverge, leading to income redistributions to the state. Overall, our evidence supports the introduction of a market-based certificate scheme to reduce land consumption in Germany due to its resilience against potential shocks.  相似文献   
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