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991.
我国的农地金融制度建设从1988年贵州湄潭县的农地金融制度试验开始,发展到目前遍地开花的农地使用权抵押贷款,经历了一个逐步成熟的发展过程。本文挑选浙江嘉兴的土地流转经营权抵押贷款和丽水的林权抵押贷款作为案例,将它与贵州湄潭农地金融制度的试验进行对比分析,试图为我国农地金融制度的构建提供有价值的参考。 相似文献
992.
This paper uses portfolio analysis to study how the Ecuadorian incentive programme for forest conservation and restoration (Socio Bosque), and an incentive programme for timber plantations, may reduce income risk and/or maximise returns for a given level of risk for farmers in the municipality of Loja. The main existing land use in the research area is milk production on pasture, with some farmers having forest land. Our results suggest that most farmers would significantly increase the area under conservation and/or restoration as part of their risk reduction strategies, compared to a decision based solely on expected returns. However, in land use allocations that maximise the return per unit of risk, a small group of milk producers without forest would continue milk production on most of their land. In addition, milk producers with forest would significantly decrease deforestation under the land use allocations made when conservation incentives are available. Against this we also identify a likely shift of milk production from existing pasture to new pasture established on deforested land, which provides evidence of a potential ‘leakage effect’. In addition, the incentive programmes would only lead to small areas of tree plantations being established. None of the land use combinations (portfolios) analysed would increase the income of all households to above the poverty line, as the monetary incentives are too low and many farms are too small. For forest holders all the land use combinations we studied would have a positive impact on income, but we observed a negative impact on household income for milk producers without forest. For producers without any forest, there seems to be a trade-off between maximising household income and risk reduction through combining incentives for restoration and tree plantations. 相似文献
993.
This paper studies the problems associated with the construction of price indexes for commercial properties that could be used in the System of National Accounts (SNA). Property price indexes are required for the stocks of commercial properties in the Balance Sheets of the country. Related service price indexes for the land and structure input components of a commercial property are required in the Production Accounts of the country if the Multifactor Productivity of the Commercial Property Industry is calculated as part of the SNA. The paper reviews existing methods for constructing an overall Commercial Property Price Index (CPPI) and concludes that most methods are biased (due to their neglect of depreciation) and more importantly, not able to provide separate land and structure subindexes. A class of hedonic regression models that is not subject to these problems is discussed. 相似文献
994.
LADM design requires the association of external land use/cover information with cadastral land parcels. In addition to model design, related specifications are to be defined in the implementation. Yet, there are many severe obstacles against defining such specifications that are applicable to all cases. In this context, there are many different types of land use/cover classification systems for different purposes in different data quality, scale and content, which are either designed internationally or nationally. FAO Land Cover Classification System (LCCS), CORINE land cover, INSPIRE land use/cover themes, land use capability classification and Land Parcel Identification System (LPIS) are common international examples.In this study, management of spatial land use/cover data in association with cadastral land parcels represented by LADM was studied in a pilot study area in Turkey. In this context, association of spatial information as sub-divisions of land parcels (sub-parcels) was studied. Different land use/cover data sets (four types) were specifically produced for this study with an LPIS like digitization method. For the association, special overlay operations with and without predefined XY tolerances were carried out. Effects of similar yet different data sets, spatial data consistency between the produced sub-parcel data sets and land parcels, and also errors were analyzed based on the results. It is found (1) that the level of detail (base production scale) of external land use/cover data set increases spatial association errors, (2) that using XY tolerances to reduce these errors causes data inconsistency and (3) that direct spatial harmonization of two data set may be a robust solution when it is possible. In this context, in order to contribute to the implementation of LADM in terms of spatial association of land parcels and external land use/cover data, together with these data processing and analysis work, LADM modelling abstraction, availability and data quality issues of external land use/cover data, updating and maintenance issues were also discussed. 相似文献
995.
针对传统自动门继电器控制的缺点,设计了一种基于PLC和自动门控制系统。系统以可编程控制器为核心,系统不断采集自动门系统各类传感器数据,通过变频器驱动电动机,实现门的自动开启和关闭,并设计了防夹和安全警报功能,阐述了可编程控制器、变频器、传感器等电路设计以及系统软件设计。 相似文献
996.
997.
The large-scale implementation of the Grain for Green project on the Chinese Loess Plateau since 1999 has greatly increased the vegetation coverage and rapidly decreased the agricultural land by converting slope cropland to planted vegetation (forest and grasslands). However, the geological, hydrological, ecological, and agricultural effects of the Gully Land Consolidation (GLC) project launched at Yan’an City in 2011 to address these land-use problems are not clearly understood. To assess the project outcomes in this region, we examined 71 of the 193 subprojects (61 treated gullies and 10 untreated gullies); measured geological, hydrological, ecological, and agricultural indices in the field; and tested disturbed (n = 447) and undisturbed (n = 142) soil samples (e.g., particle size distribution, saturated hydraulic conductivity, bulk density, and heavy metal contents). We found that: (1) slope stability improved for 67 % of the subprojects, (2) severe swamping was found only for 2 % of the subprojects, (3) the average increase in NDVI was 0.0231, 69 % of treated gullies NDVI was increased, and (4) crop yield was overall improved. There were no significant differences between the treated and untreated gullies in soil texture, saturated hydraulic conductivity, bulk density, or heavy metal contents (Cr, Zn, Cu, Ni, Pb), although particle size contents (range of 0.05 mm – 0.20 mm) differed significantly (p < 0.05). To promote successful gully land consolidation, the GLC project should (1) prioritize slope stability and long-term maintenance of water preservation facilities in gullies, (2) use bioengineering to accelerate the maturation of newly created land, or develop new cropping system after the GLC project; (3) on the basis of Grain for Green, integrate the GLC project, and modern agriculture to be complementary. 相似文献
998.
The evaluation of the extent to which urban and land use planning have achieved their objectives is crucial to better management of urban land development. China’s urban and land use plans have the common purpose of controlling urban sprawl. This research aimed at comparatively assessing the consistency and implementation of these plans, considering the Changping District in suburban Beijing as a case study. Three main findings were obtained: (1) each plan used different strategies to control new developments, and there were several quantitative and spatial conflicts between the two plans; (2) neither plan has been well implemented or effective in controlling urban sprawl, despite the slightly better performance of the land use plan; (3) core-periphery decreasing trends were revealed in land quota allocation and effectiveness of planning implementation. Remote regular towns received the least land resources from the top-down planning system but also developed fast, mainly through informal and illegal approaches. Further investigation into the double failure of China’s current spatial planning system in quantitative and spatial control over urban land development requires a deeper integration of various spatial management systems, a fundamental transformation of planning philosophy, and a higher respect for peripheral areas in urban-rural integration. The planning assessment approach and reform recommendations developed on the basis of the Chinese practice are probably referable for other developing countries facing similar processes of rapid urbanization and imperfect spatial management. 相似文献
999.
1000.
征地报批周期长短是影响建设项目能否顺利落地实施的重要因素,事关用地企业的直接经济利益,事关城市建设和经济社会发展。本文以征地报批时间周期为主要研究对象,通过对常州市新北区2018年度25个征地项目报批周期的统计分析,详细阐明了影响征地报批周期长短的主要原因。结合我市征地报批工作实际,并借鉴其他城市的先进做法,提出了缩短报批周期、提高报批效率以确保及时满足企业用地需求的可行性建议和对策。 相似文献