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71.
Most small-scale social economies are characterised by their deficiency, lack, and/or difficulty in matching natural data. Against this backdrop, this paper builds a relatively uniform theoretical framework and designs a more economical and objective method for demarcating ecological conservation redlines (ECR) based on sensitivity assessment of ecosystem services. The results show that the sensitivity assessment model designed in this study can identify sensitive zones effectively, and that the ECR in Hubei Province are well within the sensitive zones so identified. The delimited areas based on the sensitive assessment of ecosystem services have great similarities (95%) with the actual ECR areas in Hubei Province. The most ecologically important functional zones (EIFZ) can also be identified using the regional ecological sensitivity coefficient. When the threshold of EIFZ is set higher, the probability that it falls within the ecologically sensitive areas is greater and the ECR delimited by the method proposed in this study will be more reliable. Theoretically, the delimitation of ECR can be inserted at any evaluation level with a grid resolution higher than that of the land use data, which can be used as a supplement to the ECR delimitation method in ecology or geography.  相似文献   
72.
Researchers have spent substantial effort to identify factors influencing pesticide use intensity. However, few studies have compared the relative importance of these factors. This study examines four categories of factors that potentially influence farmers’ pesticide use decisions by evaluating incentivized experiment data, farm survey data, and remote sensing data in China. Our results suggest that land diversification has the largest effect on farmers’ pesticide use. Compared with the most rice-intensive landscape type, less rice-intensive systems cause farmers to spray less on middle rice. Heavy pesticide use intensity is associated with land fragmentation as small-scale farms still dominate crop production. Farmers’ integrated pest management knowledge has significant effects on pesticide use. We also find that loss and ambiguity preferences, rather than risk preferences, are more likely to affect pesticide use intensity.  相似文献   
73.
研究目的:探讨对集聚农户共生、集聚区土地利用率提高的影响因素,为提升农户共生的认知水平、优化农户共生关系及促进资源的节约集约利用提供有效路径及理论指导。研究方法:参与式农户调查,结构方程模型。研究结果:(1)户主自身特征、农户家庭特征、集聚共生效益特征及外部环境与政策特征这4类外源潜变量对农户共生认知产生重要影响且影响程度大小不同,其中,集聚共生效益特征的影响最为显著,外部环境与政策特征、户主自身特征和农户家庭特征的影响依次减弱;(2)是否为干部、对原集聚模式的满意度、是否促进农户生产生活条件和政府对集聚区的补贴力度分别对这4类外源潜变量具有较好的解释能力。研究结论:显化农户共生效益、增强"精英"农户及村干部的正向引导、提升农户成员受教育水平、培养农户"共生共荣"理念等是深化农户共生关系,促进和谐乡村人居环境建设的重要路径。  相似文献   
74.
Shortfalls in global food production, coupled with the growing visibility of climate change's disruptive effects, have underlined for many observers the importance of devoting rural lands to their ‘optimal’ use, where they can make maximal contributions to the global imperatives of feeding the human population and maintaining vital environmental services. In this context observers have endorsed rural land use planning as a way to insure that, at least in theory, lands get devoted to their best uses. In practice, land use planning in the developing world has resembled ‘organized anarchy’. Small landholders with insecure land tenure, overseas investors seeking large land deals, NGOs representing indigenous peoples, government officials, and staff from international environmental NGOs and multilateral organizations have come together in strategic action fields to struggle over and sometimes negotiate land use plans for contested landscapes. These plans represent a strategic, spatially explicit response to the climate change–biodiversity–food security crisis.  相似文献   
75.
The conservation and management of protected areas in urban settings has become increasingly challenging with dynamics over land use change in adjacent urban areas being highly relevant to, but at times conflicting with, the protected area. This study seeks to better understand the implications of land use change processes to urban protected area management through the case study of the Las Piñas – Parañaque Critical Habitat and Ecotourism Area (LPPCHEA) in Metro Manila, Philippines. Factors and processes influencing land use change and protected area management and the impact of stakeholders’ perceptions on protected area were analyzed. The urban protected area in itself has limited influence on its surrounding urban areas, as land use change in these areas is shaped more by social, economic and policy/institutional factors occurring within the context of urban-regional development. The study also found that land use conflict is evident in an urban protected area due to the competing ecosystem services derived by various stakeholders. This discord is deepened by the lack of coordination between land use planning and protected area management. Integrating protected area management with land use planning through legally binding instruments, specific timeframes and clear internal procedures can help resolve land use conflict for an urban protected area at the strategic or policy level.  相似文献   
76.
Land use transitions are rated among the leading sources of greenhouse gas emissions in the tropics. They significantly challenge the functioning of ecosystems and affect multi-temporal stability of greenhouse gases such as N2O and soil properties. Studies on dynamics in nitrogen balances are essential in understanding greenhouse gas emissions such as N2O and to manage their impacts on productivity. In this study, multi-temporal Landsat images (1975, 1995 and 2012) were classified to determine land use transitions and potential drivers. The classified images were categorized into degraded and non-degraded lands and eighty sampling plots generated within the entire study area. Soil samples were then collected at 0–15, 15–30 and 30–60 cm depths on each plot and soil nitrogen determined. A regression analysis was developed to determine the influence of forest and grassland degradation on soil nitrogen. Results indicated a significant change in major land use and land cover types. Specifically, there was a decrease in areas covered by forests, woodland and grassland, however, area covered by less dense forest increased. Results also indicated variability in mean nitrogen content between degraded and non-degraded areas and depths. Furthermore, levels of degradation influence nitrogen content up to a soil depth of 30 cm. The present study is relevant in the detailed assessment of the extent of damage and threats posed to biodiversity hotspots in sub-Saharan Africa. These results are transferable to other parts of the world characterized by dynamic ecological transformation.  相似文献   
77.
Urban vacation rentals, a phenomenon that has grown explosively very recently, bring benefits to cities but also impose quality of life and housing market impacts on neighborhoods. As a consequence, cities are beginning to grapple with creating regulatory regimes for managing this new land use and its encroachments on residential areas. This article uses webscraped data from Airbnb, the industry leader, to analyze the geographical patterns and concentrations of these impacts in five US cities: Austin, Boston, Chicago, San Francisco, and Washington, DC. It uses the findings to put forth four general principles for cities seeking to manage impacts imposed by Airbnb and its competitors. These are that webscraping is an imperfect but relatively cheap and effective means of gathering locally specific data; that “spiky” usage patterns dictate a microgeographic approach to regulation; that meaningful regulation necessitates dedicated enforcement, likely paid for with permit fees; and that it is desirable to distinguish between “mom-and-pop” hosts and those operating at a commercial scale.  相似文献   
78.
研究目的:从居民的通勤行为特征中寻求小城镇土地利用格局优化路径,为产城融合的实现提供理论支持。研究方法:构建通勤流矩阵,运用Arc GIS路径分析测算通勤距离,并通过缓冲区分析通勤距离在空间上的特征,并与土地利用类型进行对比分析,同时建立通勤距离与社会经济因素的回归方程,分析通勤距离的影响因素。研究结果:小城镇通勤方式以便捷型工具为主,通勤高峰集中于上下班,通勤距离随着城镇化和工业化水平的提高,短距离占比增大。主要结论:在城镇化和工业化发展较快的区域,短距离通勤集聚更具有"同心圆"特征,核心力更强。工业化带动的聚集结构呈现出"条带形"态势,与区域工业布局结构有较密切的关系,也与城镇化和工业化扩增融合有关。短距离通勤集聚区会随着城镇化水平的提高而由"双核"向"单核"结构发展,并针对以上问题提出了相应的对策。  相似文献   
79.
The analysis of game farming is set in the Eastern Cape, South Africa. Game farming reorders the use, meaning and value of land and animal species. However, what it means for rural development processes in the immediate region and beyond is not well accounted for. We perceive game farming as an assemblage that brings together new actors, new forms of land use and new discourses. We argue that although game farming has generated new opportunities and new forms of added value to the available resources (e.g. eco-tourism, trophy hunting, game-meat production), situated in the history and contemporary context of the Eastern Cape, it is a contested, and from a development point of view, problematic land-use practice. We argue that game farming constrains land and agrarian reforms: the distribution of land and income remains skewed; ‘poaching’ occurs and game farms do not, or only minimally, generate new and badly needed employment opportunities. The game farm has emerged as an exclusive, globally well-connected space. The nature of the relationships this space maintains with the surrounding communities is, however, such that the overall contribution to rural development in South Africa is questionable.  相似文献   
80.
Objective:

To define the in-hospital and 6-month post-discharge resource use, following Transcatheter Aortic Valve Implantation (TAVI) and conventional Aortic Valve Replacement (AVR) surgery within a single UK hospital.

Methods:

A local service evaluation of patients undergoing TAVI or AVR between January 2011 and May 2012 captured data until 6-months post-procedure, collected from hospital records and via a General Practitioner questionnaire. The main end-points were mortality, time in ITU/HDU, hospital length of stay (LoS), discharge destination, re-admission, and post-discharge primary/secondary care resource use. Sub-group analyses were performed for AVR patients aged ≥80 (AVR?≥?80) and with EuroSCORE of ≥10 (AVR ES?≥?10) to allow more direct comparison with ‘TAVI type’ patients.

Results:

Results are given as means (standard deviation) for TAVI (n?=?51), AVR (n?=?188), AVR?≥?80 (n?=?48), and AVR ES?≥?10 (n?=?47), respectively, unless otherwise stated. Age in years was 83.0 (8.1), 71.2 (13.1), 84.1 (2.7), 79.4 (7.1); EuroSCORE was 24.7 (11.9), 8.1 (6.4), 12.0 (6.0), and 16.5 (6.6); post-operative LoS (days) was 11.5 (11.2), 10.9 (10.8), 14.3 (16.7), and 15.2 (17.7). For discharged patients, 0%, 7%, 13%, and 9% had unplanned cardiac-related re-admissions within 30-days of discharge. Time to first readmission was 74.6 (34.0), 35.0 (34.2), 20.8 (9.7), and 22.6 (14.3) days.

Limitations:

This was a single-center retrospective evaluation, not prospectively powered to confirm differences in outcomes.

Conclusions:

Despite TAVI being performed in an older, higher risk population, LoS was similar to AVR. Most strikingly there were no cardiac-related re-admissions within 30-days for TAVI and time to first re-admission was significantly longer. This evaluation suggests that TAVI is clinically appropriate and provides economic advantages in both the hospital and post-discharge setting in this high risk group. Many patients undergoing TAVI are considered unfit for surgery and, hence, TAVI offers a treatment that delivers similar results to traditional AVR without the high risk associated with surgery.  相似文献   
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