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1.
湖北省土地资源遥感调查与评价   总被引:4,自引:1,他引:3  
根据1999年TM影像解译了湖北省土地利用现状,然后以土地利用现状图为基础,采用地理信息系统技术,结合湖北省的实际情况,选择土壤、地形、坡度等评价因子,对湖北省土地资源进行了适宜性评价,简要地将全省土地资源划分为九等。评价结果表明:湖北省水热条件好,土地适宜性广,宜农林牧业同时利用的土地广泛分布;但是该省的基本农田面积小,土地垦殖率高,低产田面积大,后备耕地资源严重不足;土地利用结构与土地资源的供给条件、利用要求不相适宜,利用效益末得到充分发挥。  相似文献   

2.
在统筹推进国土空间规划及用途管制的背景下,揭示土地发展权受限的数量及其价值,对于完善中国空间治理体系、解决不平衡不充分发展尤其是区域差异问题具有重要的理论和现实意义。文章以湖北省为"生态资源优势区"代表性省份,首先运用柯布-道格拉斯(C-D)生产函数模型测算各生产要素在农业与非农业部门中对经济增长的弹性以及土地资源在两部门的边际收益,揭示土地发展权受限的客观现实和成因;然后基于缩小湖北省与"经济发展优势区"经济发展差距的不同情景,测度2009—2018年湖北因处于生态资源优势区而使土地发展权受限的数量与价值。结果显示:(1)土地要素投入对湖北省经济增长具有重要影响。2009—2018年,湖北省非农部门经济增长仍依赖土地要素投入,且土地要素对经济增长的贡献难以被其他生产要素替代。(2)高额的机会成本是土地资源由农业部门向非农部门转移的重要潜在驱动力。2009—2018年,湖北省非农部门的土地边际收益是农业部门的17.03~44.14倍,且呈逐年递增趋势,规划管制的存在导致了土地发展权受限。(3)规划管制背景下,对受限的土地发展权进行补偿具有必要性和可行性。在经济发展水平差距缩小10%~100%的不同情景下,2009—2018年湖北省土地发展权受限数量处于0.53×104~5.35×104hm2之间,对应的价值量占同时期"经济发展优势区"总GDP的比重较低,为0.02%~0.19%。基于此,应开展土地发展权受限补偿的制度建设,从土地发展权产权确认和利益分配机制改革两方面量化和落实土地发展权,并以对土地发展权的底线补偿情景为起点逐步提高土地发展权补偿水平,直至实现完全补偿。  相似文献   

3.
Commercial and small-scale farmers in South Africa are exposed to many challenges. Interviews with 44 farmers in the upper Thukela basin, KwaZulu-Natal, were conducted to identify common and specific challenges for the two groups and adaptive strategies for dealing with the effects of climate and other stressors. This work was conducted as part of a larger participatory project with local stakeholders to develop a local adaptation plan for coping with climate variability and change. Although many challenges related to exposure to climate variability and change, weak agricultural policies, limited governmental support, and theft were common to both farming communities, their adaptive capacities were vastly different. Small-scale farmers were more vulnerable due to difficulties to finance the high input costs of improved seed varieties and implements, limited access to knowledge and agricultural techniques for water and soil conservation and limited customs of long-term planning. In addition to temperature and drought-related challenges, small-scale farmers were concerned about soil erosion, water logging and livestock diseases, challenges for which the commercial farmers already had efficient adaptation strategies in place. The major obstacle hindering commercial farmers with future planning was the lack of clear directives from the government, for example, with regard to issuing of water licences and land reform. Enabling agricultural communities to procure sustainable livelihoods requires implementation of strategies that address the common and specific challenges and strengthen the adaptive capacity of both commercial and small-scale farmers. Identified ways forward include knowledge transfer within and across farming communities, clear governmental directives and targeted locally adapted finance programmes.  相似文献   

4.
精准识别农村潜在土地利用冲突是预先权衡和协调冲突用地,指导农村和谐发展的重要基础。以西峡县东坪村为例,综合考虑"发展建设—农业生产—生态维护"多重土地利用目标,进行建设用地、农业用地和生态用地的用地倾向性评价,建立倾向性比较矩阵识别潜在土地利用冲突区域,并根据识别成果提出相应的差别化管理建议。结果表明:东坪村有47%的土地存在明显潜在土地利用冲突的风险,包括冲突一般区和冲突激烈区,分别占土地总面积的20.61%和26.39%。冲突激烈区(J)中J1涉及面积最大,占土地总面积的18.84%,是接下来土地利用工作中亟需防治的重点问题。除此之外,用地优势区和冲突微弱区分别占土地总面积48.13%和4.87%。总体来看,东坪村内潜在土地利用冲突范围较大,程度较强,冲突形势较为严峻。  相似文献   

5.
China-Africa development cooperation in the rural sector has received an increased attention by researchers and policy-makers given the advantages and disadvantages of China’s contribution to the local economy. However, there is a lack of more reliable and nuanced findings to provide greater insights into the major issues concerning rural development and resource use. This paper aims to position land tenure and foreign investments linkages as a new research angle for understanding the role of land in sustainable resource use and investments. The paper provides a brief overview of China-Africa cooperation in rural development especially concerning agriculture to illustrate the neglect of critical land and resource use issues in policy and practice. The paper briefly discusses the ongoing land tenure reforms in Africa and the policy gaps to be filled through further research. It also discusses how China’s own development model, especially concerning land tenure reform, shares similar trajectories with Africa, which has important implications for the effectiveness of Chinese investments in African land. The paper concludes that there is an urgent need for lesson learning among Chinese and African policy-makers and investors towards tailoring development cooperation to more appropriate land tenure systems for sustainable resource use to the mutual benefit of Chinese and African stakeholders.  相似文献   

6.
CSIRO Sustainable Ecosystems is constructing a spatially explicit modelling system capable of exploring alternative land and water policy alternatives against plausible price, cost, and climate scenarios for the next 20 years. INSIGHT will be used to identify the likely impacts of land and water policy options on regional economies and structural adjustment. Flowcharts have been constructed for most of the major crop and pasture and associated economic models for commodities produced in the Lachlan River Catchment of New South Wales. This enabled the most important components and interrelationships within these models to be readily identified. The next step has been to construct models at the regional scale that contain the essential elements of the more-detailed point models. The paper describes the progress to date in describing these models, and how they have been integrated into a coordinated agricultural crop production evaluation system.  相似文献   

7.
On-farm tree cultivation is considered an important strategy to mitigate detrimental environmental impacts of agricultural land-use change (ALUC). In South Africa, however, little is known about farm-level incentives and constraints that govern ALUC decisions among small-scale farmers. To address this knowledge gap, this study employs a mixed multinomial logit model by using a combination of revealed and stated preference data. After correcting for endogeneity, the estimated results show that decisions about ALUC are rationally derived and driven by clear but heterogeneous preferences and trade-offs between crop productivity, food security and labour saving. The results further show that the decision to plant sugarcane is constrained by landholding, whilst farmland afforestation is negatively influenced by household size. Decisions to convert land use are also driven by the behaviour of peer groups and agro-ecological conditions. Based on these findings, important policy implications for sustainable land use are outlined.  相似文献   

8.
A study was conducted to investigate hydrological impacts of land cover changes in the degradation of the hydrological on flow regimes of the Upper Shire river, Malawi. Remote sensing techniques were used to inventory temporal changes of land cover changes in the catchment. Hydrological data were analyzed to reveal the alterations and trends for two periods; 1989 and 2002. The study revealed significant changes in magnitude and direction that have occurred in the catchment between 1989 and 2002, mainly in areas of human habitation. Trends in land cover change in the Upper Shire river catchment depict land cover transition from woodlands to mostly cultivated/grazing and built-up areas. The land cover mapping showed that 23% of the land was covered by agricultural land in 1989. Subsistence agricultural area has increased by 18%, occupying 41% of the study area in 2002. The effects of the derived land cover changes on river flow in the Upper Shire river were investigated using the semi distributed soil and water assessment tool (SWAT) model. River flows were found to be highly variable and sensitive to land cover changes. Simulation results show that 2002 land cover data produces higher flow peaks and faster travel times compared to the 1989 land cover data. The changes detected indicate the effects of land use pressure in the catchment. The study highlights the importance of considering effects of land use and land cover changes on ecosystems, and water resources for an informed decision on proper catchment planning and management.  相似文献   

9.
Regional models of land use change are evaluated as a way of identifying land use pattern based on recent quantitative and probabilistic approaches. Differentiation between models in this area is the result of the approach to the concept of land use and type of indicators used in the modeling process. Since the determination of the optima land use pattern, due to the different uses of land based on the availability of regional capabilities and spatial difference in land use, depends on an integrated model, there must be a model that can assess the existing conditions of the region and present reasonable models of land use according to regional capacities and potentials. In this research, we developed a model to present the Optimal Land Use Allocation Pattern (OLUAP) for maximizing the advantages of change and determining the methods of influencing land use change priorities. This model uses spatial models and analysis, moderates the cost-benefit function, and calculates the allocation priorities of various areas based on regional conditions. The model results show that a wide scope of Nowshahr area is allocated to natural and agricultural uses. At the same time, a limited area has been assigned to urban and industrial uses. In addition, it shows that northern strip of the region due to higher accessibility of services and infrastructures is more suited than other regions to urban and industrial areas, and these two uses have first and second priority, respectively. Besides, according to the man-made environment and the special environmental conditions, the model allocates the central lowlands and southern parts sporadically to agricultural and natural areas as first and second priorities. Since the model is spatial optimization, the suggestions of the model show the OLUAP. Therefore, one can see the optimal condition for each plot and compare it with the existing land use.  相似文献   

10.
While impacts of climate change on agricultural systems have been widely researched, there is still limited understanding of what agricultural innovations have evolved over time in response to both climatic and non-climatic drivers. Although there has been some progress in formulating national adaptation policies and strategic planning in different countries of South Asia, research to identify local-level adaptive strategies and practices is still limited. Through eight case studies and a survey of 300 households in 15 locations in India, Nepal and Bangladesh, this paper generates empirical evidence on emerging agricultural innovations in contrasting socio-economic, geographical and agro-ecological contexts. The study demonstrates that several farm practices (innovations) have emerged in response to multiple drivers over time, with various forms of institutional and policy support, including incentives to reduce risks in the adoption of innovative practice. It further shows that there is still limited attempt to systematically mainstream adaptation innovations into local, regional and national government structures, policies and planning processes. The paper shows that the process of farm-level adaptation through innovation adoption forms an important avenue for agricultural adaptation in South Asia. A key implication of this finding is that there is a need for stronger collaborations between research institutions, extension systems, civil society and the private sector actors to enhance emerging adaptive innovations at the farm level.  相似文献   

11.
Changing unsustainable natural resource use in agricultural landscapes is a complex social–ecological challenge that cannot be addressed through traditional reductionist science. More holistic and inclusive (or transdisciplinary) processes are needed. This paper describes a transdisciplinary project for natural resource management planning in two regions (Eyre Peninsula and South Australian Murray-Darling Basin) of southern Australia. With regional staff, we reviewed previous planning to gain an understanding of the processes used and to identify possible improvement in plan development and its operation. We then used an envisioning process to develop a value-rich narrative of regional aspirations to assist stakeholder engagement and inform the development of a land use management option assessment tool called the landscape futures analysis tool (LFAT). Finally, we undertook an assessment of the effectiveness of the process through semi-structured stakeholder interviews. The planning process review highlighted the opinion that the regional plans were not well informed by available science, that they lacked flexibility, and were only intermittently used after publication. The envisioning process identified shared values—generally described as a trust, language that is easily understood, wise use of resources, collaboration and inclusiveness. LFAT was designed to bring the best available science together in a form that would have use in planning, during community consultation and in assessing regional management operations. The LFAT provided spatially detailed but simple models of agricultural yields and incomes, plant biodiversity, weed distribution, and carbon sequestration associated with future combinations of climate, commodity and carbon prices, and costs of production. Stakeholders were impressed by the presentation and demonstration results of the software. While there was anecdotal evidence that the project provided learning opportunities and increased understanding of potential land use change associated with management options under global change, the direct evidence of influence in the updated regional plan was limited. This project had elements required for success in transdisciplinary research, but penetration seems limited. Contributing factors appear to be a complexity of climate effects with economic uncertainty, lack of having the project embedded in the plan revision process, limited continuity and capacity of end users and limited after project support and promotion. Strategies are required to minimise the controlling influence that these limitations can have.  相似文献   

12.
Regional change under agricultural expansion in the Chaco of Argentina is determined by interactions of rainfall change, infrastructure development, socio-economic actions and values, and the social perceptions of change. Our study focused on adaptation in the socio-environmental system which is the key to understanding opportunities, uncertainties and risk in the context of historical change. Change in land use from extensive grazing through mixed farming and on to industrial-scale soybean production was made possible by a trend of increasing rainfall that reduced the risk of crop failure from drought since the 1970s. Rainfall change coincided with a period in which the Chaco forest was suffering extensive degradation from long-term extractive use. The degradation aided agricultural expansion since the degraded state of the ecosystem justified public policies of deforestation. In parallel to these resource-based processes, public policy changed in the late 70s and 80s toward favoring privatization of state land and exclusion of small producers. This permitted the land concentration needed for industrial-scale production. Technological innovation in both water and land resource management reinforced the process of concentration because small producers rarely have the financial or educational capital to develop or implement emerging technologies. One of the results of the intensification and expansion of agriculture is that soil surface sealing, waterlogging and flood risk are now effective at a landscape scale. To address these risks, private enterprise and government efforts must now come together toward innovative policies in integrated landscape management.  相似文献   

13.
Physical and ecological responses of the coastal areas in the vicinity of Mumbai, India, due to relative sea level rise are examined by different inundation scenarios. Evaluation of potential habitat loss under sea level rise was made by incorporating the land use/land cover (LULC) adopted from the digital elevation model with the satellite imagery. LULC categories overlaid on 1.0, 2.0, 3.0 and 4.0 m coastal elevation showed that the coastal areas of Mumbai were mostly covered by vegetation followed by barren land, agricultural land, urban areas and water bodies. For the relative sea level rise scenarios of 1.0, 2.0, 3.0 and 4.0 m, the tidal inundation areas were estimated to be 257.85, 385.58, 487.56 and 570.63 km2, respectively, using GIS techniques. The losses of urban areas were also estimated at 25.32, 41.64, 54.61 and 78.86 km2 for the 1.0, 2.0, 3.0 and 4.0 m relative sea level rise, respectively, which is most alarming information for the most populated city on the eastern coast of India. The results conclude that relative sea level rise scenario will lead profound impacts on LULC categories as well as on coastal features and landforms in the adjoining part of Mumbai. The sea level rise would also reduce the drainage gradients that promote flooding condition to rainstorms and subsequently increase saltwater intrusion into coastal regions. Alterations in the coastal features and landforms correlated with inundation characteristics that make the coastal region more vulnerable in the coming decades due to huge development activities and population pressures in Mumbai.  相似文献   

14.
District Swat is part of the high mountain Hindu-Kush Himalayan region of Pakistan. Documentation and analysis of land use change in this region is challenging due to very disparate accounts of the state of forest resources and limited accessible data. Such analysis is, however, important due to concerns over the degradation of forest land leading to deterioration of the protection of water catchments and exposure of highly erodible soils. Furthermore, the area is identified as hotspot for biodiversity loss. The aim of this paper is to identify geophysical and geographical factors related to land use change and model how these relationships vary across the district. For three selected zones across the elevation gradient of the district, we analyse land use change by studying land use maps for the years 1968, 1990 and 2007. In the high-altitude zone, the forest area decreased by 30.5 %, a third of which was caused by agricultural expansion. In the mid-elevation zone, agriculture expanded by 70.3 % and forests decreased by 49.7 %. In the lower altitudes, agriculture expansion was 129.9 % consuming 31.7 % of the forest area over the forty-year time period. Annual deforestation rates observed were 0.80, 1.28 and 1.86 % in high, mid and low altitudes, respectively. In the high-altitude ecosystems, accessibility (distance to nearest road and city) had no significant role in agriculture expansion; rather land use change appears significantly related to geophysical factors such as slope, aspect and altitude. In the low-elevation zone, accessibility was the factor showing the closest association with agriculture expansion and abandonment. The analysis illustrates that land use change processes vary quite considerably between different altitudinal and vegetation cover zones of the same district and that environmental constraints and stage of economic development provide important contextual information.  相似文献   

15.
近年来,农村居民点整理被作为城乡统筹发展的重要措施,在各地广泛开展。其在改善农民居住环境、为工业化和城镇化发展置换建设用地空间的同时,也对区域农地资源可持续利用产生了巨大冲击,其中,土地投入变化是农户响应这些冲击的重要表现。本研究沿着"农村居民点整理-区域土地利用条件变化-农户土地利用行为响应"的逻辑思路,形成了农村居民点整理对农户土地投入影响的分析框架,并在此基础上,从总体效应和不同政策影响两个层次,构建了农村居民点整理对农户土地投入影响的两个模型。依据江苏省调研数据,从资金和劳动力两个方面,实证分析农村居民点整理项目对农户土地投入的净效应,以及不同居民点整理政策对农户土地投入的影响方向和大小。结果表明,农村居民点整理促进了农户的土地资金投入,但对农户的土地劳动力投入具有负向影响。不同居民点整理政策对农户土地投入的影响具有显著差异,其中,置换住房的宅基地补偿政策和农地产权稳定政策对农户的土地资金投入具有较好的积极作用,而安置公寓房政策则更可能带来农户土地资金投入减少;农地产权稳定政策和安置公寓房政策显著负向影响农户土地劳动投入,但宅基地补偿政策对农户土地劳动投入影响不显著。本研究对这些结果进行了合理解释,同时也估算了户主年龄、户主受教育程度、农业收入比例、非农就业水平、农业补贴收入、耕作距离和土地经营面积等控制变量对农户土地投入的影响情况。最后从强化规划引导、内涵拓展、宅基地补偿策略优化、土地流转制度完善等方面,提出农村居民点整理政策调整和合理引导农户土地投入行为的对策建议。  相似文献   

16.
This study employed geographic information systems (GIS) technology to evaluate the vulnerability of groundwater to pesticide pollution in Thailand. The study area included three provinces, Kanchana Buri, Ratcha Buri, and Suphan Buri, located in west-central Thailand. Factors used for the vulnerability assessment included soil texture, slope, land use, well depth, and rainfall. These vulnerability factors were reclassified to a common scale, and a weighted average was computed to yield a vulnerability score. Vulnerability factors and weights were assigned considering pesticide concentrations in 90 wells throughout the study area. Well depth was the most significant vulnerability factor. Groundwater vulnerability maps were generated for several pesticides. The eastern, agricultural part of the study area has relatively deep wells and fine soils. Shallow wells are present in the mountainous west; however, fewer pesticides are applied in that region. Consequently, much of the study area had a medium groundwater vulnerability rating, although there were pockets of high vulnerability, for example, in agricultural areas with shallow wells. The groundwater vulnerability maps are effective for identifying locations warranting more detailed groundwater pollution and vulnerability investigations.  相似文献   

17.
Carbon dioxide emissions due to fossil fuel consumption are well recognized as a major contributor to climate change. In the debate on dealing with this threat, expectations are high that agriculture based economies of the developing world can help alleviate this problem. But, the contribution of agricultural operations to these emissions is fairly small. It is the clearing of native ecosystems for agricultural use in the tropics that is the largest non-fossil fuel source of CO2 input to the atmosphere. Our calculation show that the use of fossil energy and the concomitant emission of CO2 in the agricultural operational sector - i.e. the use of farm machinery, irrigation, fertilization and chemical pesticides - amounts to merely 3.9% of the commercial energy use in that part of the world. Of this, 70% is associated with the production and use of chemical fertilizers. In the absence of fertilizer use, the developing world would have converted even more land for cultivation, most of which is completely unsuitable for cultivation. Current expectations are that reforestation in these countries can sequester large quantities of carbon in order to mitigate excessive emissions elsewhere. But, any program that aims to set aside land for the purpose of sequestering carbon must do so without threatening food security in the region. The sole option to liberate the necessary land for carbon sequestration would be the intensification of agricultural production on some of the better lands by increased fertilizer inputs. As our calculations show, the sequestration of carbon far outweighs the emissions that are associated with the production of the extra fertilizer needed. Increasing the fertilizer use in the developing world (without China) by 20%, we calculated an overall net benefit in the carbon budget of between 80 and 206 Mt yr?1 dependent on the carbon sequestration rate assumed for the regrowing forest. In those regions, where current fertilizer use is low, the relative benefits are the highest as responding yield increases are highest and thus more land can be set aside without harming food security. In Sub-Saharan Africa a 20% fertilizer increase, which amounts to 0.14 Mt of extra fertilizer, can tie up somewhere between 8 and 19 Mt of CO2 per year (average: 96 t CO2 per 1 t fertilizer). In the Near East and North Africa with a 20%-increased fertilizer use of 0.4 Mt yr-1 between 10 and 24 Mt of CO2 could be sequestered on the land set aside (40 t CO2 per 1 t fertilizer). In South Asia this is 22–61 Mt CO2 yr?1 with an annual additional input of 2.15 Mt fertilizer (19 t CO2 per 1 t fertilizer). In fact, carbon credits may be the only way for some of the farmers in these regions to afford the costly inputs. Additionally, in regions with already relatively high fertilizer inputs such as in South Asia, an efficient use of the extra fertilizer must be warranted. Nevertheless, the net CO2 benefit through implementation of this measure in the developing world is insignificant compared to the worldwide CO2 output by human activity. Thus, reforestation is only one mitigating measure and not the solution to unconstrained fossil fuel CO2 emissions. Carbon emissions should, therefore, first of all be reduced by the avoidance of deforestation in the developing world and moreover by higher energy efficiency and the use of alternative energy sources.  相似文献   

18.
地形作为重要的自然基底因子,在很大程度上影响土地利用变化与空间格局形成。以重庆市巴南区为例,借助GIS和RS手段,利用Landsat TM遥感数据和DEM数据,采用地形位指数、分布指数和土地利用程度综合指数等计算方法,对巴南区2000、2010和2015年土地利用格局与变化的地形梯度分布特征进行了分析,探讨了土地利用格局与变化和地形梯度的相互关系,以期为相似地形条件下的山地城市边缘区的人地关系研究提供支撑或参考。研究结果表明:(1)巴南区土地以中、高级地形位为主,海拔200 m以下,坡度8°以下的土地资源较为匮乏;(2)研究期内,中、低级地形位区间内大量耕地转变为建设用地,土地分布结构变化导致二者的分布优势区间均向更高级地形位区间转移;(3)土地利用程度综合指数曲线呈倒“V”型,波峰逐渐向中级地形位区间移动,可以印证在研究期内巴南区低丘缓坡区域内土地利用强度逐渐提升。  相似文献   

19.
以取消农业税和加大农业补贴力度为主要特征的农村税费改革,是近年来中国农村地区的一次重大制度改革。为探讨其对农业土地利用的影响,在简要回顾农村税费改革主要历程的基础上,通过构建计量经济模型,从宏观层面分析验证了农村税费改革对农业土地利用规模和利用效率的具体影响。结果表明: 农村税费改革对农业土地利用的影响主要体现为农户行为响应产生的引致效应;无论是农业税的取消还是财政支农政策的加强都对农业土地利用规模的扩大产生了显著影响;而农村税费改革对农业土地利用效率的影响则并不明显。为此,中国政府今后仍需在农业补贴支出结构以及相关配套政策创新方面进一步优化  相似文献   

20.
以河流近域土地利用构成与水环境质量间定量关系为研究对象,基于巢湖流域40个水质监测断面和320个河流近域作用区,运用GIS空间分析功能计算不同尺度作用区内土地利用构成,借助相关分析、冗余分析(RDA)等数理统计手段,分析土地利用构成与水质指数间的相关关系;并分析和比较了流域内山区和平原地区土地利用构成与水质之间关系。结果表明,巢湖流域近河道地区土地利用构成对各水质指数有重要影响,且受地形因素影响。其中,建设用地对河流水质恶化具有明显作用;河流沿岸林地布局能显著改善水质,尤其是对氨氮和高锰酸盐指数敏感;耕地面积变化与水质相关性不显著。RDA冗余分析证实了不同尺度下的土地利用类型对水环境影响具有尺度效应。研究成果对巢湖流域水环境管理具有重要的实际指导意义,并为同类研究提供借鉴  相似文献   

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