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991.
基于生态重建的石漠化山区土地整理项目规划   总被引:3,自引:1,他引:2  
李灿  罗海波 《农业工程学报》2011,27(12):324-329
实现石漠化山区土地持续利用最有效的方式即是通过生态重建,而土地整理正是改造土地利用的有效选择,通过把生态恢复措施融入土地整理规划设计中,能有效地实现土地整理和石漠化治理的双重目的.该文通过土地整理项目规划实例,规划方案以生态重建为核心内容,具体分析了不同地表形态与土地平整工程、岩溶环境与农田水利设计、植被恢复与农田林网建设以及生态系统保护与道路建设的规划设计方法;并对项目工程设计结果从农田建设和生态恢复两方面进行了跟踪监测,结果表明,基于生态重建前提下的石漠化山区土地整理项目规划,是改善石漠化山区生态环境和实现土地持续利用的有益探索.  相似文献   
992.
基于规则库的三维土地整治规划   总被引:1,自引:0,他引:1  
为采用信息技术提高土地整治规划的质量和规划效率,改进土地整治规划要素三维可视化布设,探索智能辅助规划。该研究尝试采用面向对象的方法表达土地整治规划知识,通过产生式推理机建立规划规则,组成规则库,与土地整治规划三维要素表达模型相关联,并利用规则在三维场景下指导土地整治智能辅助规划。指出了用该方法实现的三维辅助规划系统可以增强土地整治规划操作的可视化和规范性,提高了土地整治规划工作的质量和效率。  相似文献   
993.
环渤海地区农村居民点用地整理分区及其整治策略   总被引:19,自引:12,他引:7  
为制定农村土地整理规划和设计城市建设用地增加与农村建设用地减少挂钩项目提供决策依据,该文以环渤海地区327个县域为评价单元,从整理潜力、整理能力和整理迫切度3方面构建农村居民点用地整理分区的概念模型,利用熵值法确定权重并计算综合评价值,运用指标判别法将研究区划分为5种类型区.研究认为,优先整理区着重推进城镇化引领型的村...  相似文献   
994.
通过分析忻州市实施"一村一品"的基础条件、发展成效、实施意义、存在问题等因素,以及其实际状况和整体目标,规划设计出今后"一村一品"发展的基本框架。  相似文献   
995.
我国稻壳生物质能源发电技术应用与产业发展规划研究   总被引:2,自引:1,他引:1  
我国的稻谷年产量约2亿t,稻壳年产生量为5 000万t。作为一种较好的生物质能源,稻壳的发电技术得到发展和应用。为此,论述了稻壳生物质能源的发电技术及应用,并提出了产业发展规划,旨在推动我国生物质能源产业的发展。  相似文献   
996.
王燕妮 《湖南农机》2011,(5):122-123
文章以我国目前的城市规划问题为导向,首先提出了当前我国城市规划从业人员呈现的各种问题,进而讨论了城市规划人才培养的核心问题,最后对目前规划人才培养中亟待解决的四大问题进行了讨论。  相似文献   
997.
Since the early 1990s, Ulaanbaatar, the capital of Mongolia, has experienced rapid rural to urban migration and population growth resulting in the growth in informal settlements across the city. The informal settlements are known as ‘ger’ districts. In response to these pressures, since the 1990s, the central government has adopted a programme of land reform and metropolitan planning. These new reforms take place in the context of a unique, post‐socialist political, economic and institutional context. The land reform process has attempted to privatise land ownership, which has traditionally resided with the state. The privatisation process was initiated under the new Constitution of Mongolia, which initiated reforms in all sectors of social and economic development, and since 2003, targeted land reform in ger districts. Running parallel, a series of urban land‐use planning schemes have been introduced to frame the development of Ulaanbaatar in the context of an emerging market economy. Although master plans for urban development have been established since the 1950s, urban land‐use planning is a new concept in this emerging market economy. The aim of this paper is to trace the rationales and challenges of implementing master plans and land privatisation processes in Ulaanbaatar. Drawing on interviews with city, national and local government officials conducted in 2009, the paper focuses on the implications of these reforms for both the government and the residents of ger districts.  相似文献   
998.
Reserves are frequently constrained in design and size by various financial, social or political factors. Maintenance of existing reserves must therefore rely on strategic management practices, and prioritization of conservation activities within them. Identification of global and regional hotspots have been effective for prioritizing conservation activities. Yet, identification of micro-hotspots, or overlapping areas of endemic and rare species that are under threat at the landscape scale, have largely been ignored. From a reserve management point of view, knowledge of critical micro-hotspots within a reserve, are focal points for directing cost effective, conservation initiatives, especially removal of invasive alien plants which are a major threat to biodiversity.Using diversity patterns of dragonfly assemblages, many endemic and threatened, within a biosphere reserve located in the core of a global biodiversity hotspot, we investigated the concept of micro-hotspots. As biosphere reserves contain zones with varying degrees of anthropogenic impact, we also investigated the value of buffer and transition zones for complementing the dragonfly fauna of the reserve core. We found a distinct micro-hotspot within the protected core zone which shows concordance for both endemism and species richness. We conclude that focused conservation actions to remove invasive alien plants within this micro-hotspot would help insure its continued integrity. Furthermore, while there is greater habitat degradation within the buffer and transition zones, they support many additional species, but not those necessarily endemic or threatened. The complementary value of buffer and transition zones therefore lies in increasing habitat heterogeneity and species richness of the whole reserve.  相似文献   
999.
Selecting a survey design to detect change through time in an ecological resource requires balancing the speed with which a given level of change can be detected against the cost of monitoring. Planning studies allow one to assess these tradeoffs and identify the optimal design choices for a specific scenario of change. However, such studies seldom are conducted. Even worse, they seem least likely to be undertaken when they offer the most insight – when survey methods and monitoring designs are complex and not well captured by simple statistical models. This may be due to limited technical capacity within management agencies. Without such planning, managers risk a potentially severe waste of monitoring resources on ineffective and inefficient monitoring, and institutions will remain ignorant of the true costs of information and the potential efficiency gains afforded by a moderate increase in technical capacity. We discuss the importance of planning studies, outline their main components, and illustrate the process through an investigation of competing designs for monitoring for declining brown bear (Ursus arctos) densities in southwestern Alaska. The results provide guidance on how long monitoring must be sustained before any change is likely to be detected (under a scenario of rather strong true decline), the optimal designs for detecting a change, and a tradeoff where accepting a delay of 2 years in detecting the change could reduce the monitoring cost by almost 50%. This report emphasizes the importance of planning studies for guiding monitoring decisions.  相似文献   
1000.
City governments are fundamental to implement international environmental agreements, such as the convention on biological diversity (CBD). Even though many of them are not directly involved in the negotiation of international agreements, which are signed by national governments, most of those agreements are in fact implemented at the city level. The importance of city governance to tackle the challenges of biodiversity loss has increased as urban population has grown enormously in the last decades, particularly in developing countries. The way cities are designed, planned and governed influences the magnitude of their direct and indirect impacts on biodiversity.This paper analyzes the relationship between cities, local governance and biodiversity. Initially, we examine the relationships between cities and biodiversity by looking at the major influences cities have on biodiversity loss or conservation within and outside the city boundaries, as well as the benefits of biodiversity conservation to cities, such as the provision of ecosystem services. The paper then moves to understand what are the main urban processes and governance mechanisms that can be improved to make cities effective to implement the directives of the CBD.Urbanization creates new challenges for biodiversity conservation. As a large part of the world’s population moves from rural to urban areas, there are changes in the link between human activities and biodiversity, and consequently to the way we should think biodiversity conservation policies. However, scarce attention has been given to understand how to make cities more biodiversity friendly, both within the urban fabric, but particularly in faraway places.  相似文献   
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