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41.
In the past few decades, urbanisation has become a major phenomenon in European cities, thus representing one of the key human land cover changes with socio-economic and environmental impacts. In the Lisbon metropolitan region it is estimated that 17% of natural and farmland have been transformed into artificial areas. Since the end of 1990s, specific EU guidelines have been issued to contain urban sprawl and preserve agricultural land. Spatial planning in Portugal obviously is integrating these assumptions into the statutory land-use master plans. But what is the performance of this land use planning system regarding land cover evolution itself? Based on the Lisbon metropolitan region (LMR), one of the major areas of urban growth in Portugal, we examine spatio-temporal land cover patterns between 1990 and 2007 by integrating cross-matrix analysis, spatial metrics, and gradient analysis. Additionally, we overlay these land cover dynamics with municipal master plans that regulate land development in order to assess the compliance levels of this land-use regulatory system. Results indicate that: artificial areas are growing by coalescence and/or by scattered development along an urban–rural gradient; agricultural land is reducing and fragmentation is increasing to enlarge peri-urban spaces; there are high levels of conversion of agricultural land into urban land in protected areas, thus showing a lack of compliance to the land use regulatory system visible in the existing gaps between the original land-use assignments of the master plan and the actual developments.  相似文献   
42.
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   
43.
We use survey data for 139,517 individuals in 25 European countries, 2002–2011, to estimate the relationship between subjective well-being (SWB) and production shares of various electricity generation technologies. The estimated relationships are taken to represent preference relationships over attributes of electricity supply systems (costs, safety, environmental friendliness, etc.). Controlling for a variety of individual and macro-level factors, we find that individuals’ SWB varies systematically and significantly with differences in the electricity mix across countries and across time. Among other results, we find that a greater share of solar & wind power relative to nuclear power and electricity from coal and oil is associated with greater SWB at all levels of income and that the implied preference for solar & wind power over nuclear power has risen drastically after the Fukushima nuclear accident.  相似文献   
44.
Land fragmentation has been identified to greatly undermine crop production in many countries. In the case of Ghana’s customary tenure system, household farmlands are relatively small and are highly fragmented. Recent agricultural drives, however, have focused on farm level interventions that are ad hoc with short-term benefits. A sustainable long-term application of land consolidation which reorganises farmlands may improve yields, reduce the cost of production and improve the incomes of farmers. The successful implementation of land consolidation depends greatly on the suitability of local conditions with respect to land tenure and land use. However, in Ghana’s customary lands, the alignment between the requirements for land consolidation and existing conditions remains unexplored. This study investigated the feasibility of land consolidation within the customary tenure by juxtaposing the local conditions of the study areas with the baseline conditions for land consolidation outlined in literature. Using both qualitative and spatial data, the study revealed some traits of convergence and divergence with respect to the baseline conditions in the study areas. For example, conditions such as the existence of land fragmentation, suitable topography and soil distribution were fully met. Conditions such as the existence of a land bank, technical expertise, and infrastructure and supportive legal frameworks were partially met. The remaining conditions such as the willingness to participate, availability of a land information system and favorable land ownership structure were non-existent. The circumstances surrounding these unmet conditions are deeply embedded in customs and traditions that hardly yield to change. Since these conditions are fundamental for land consolidation, their absence negates the feasibility of land consolidation under the current tenure system of the study areas.  相似文献   
45.
46.
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   
47.
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   
48.
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   
49.
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   
50.
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   
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