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31.
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   
32.
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   
33.
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   
34.
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   
35.
Land use change is strongly modifying the traditional landscape of hilly productive Mediterranean sites. An example of these circumstances is the Langhe region (Piemonte, NW Italy), where woody plantations such as vineyards and orchards have been cultivated on hillslopes for centuries. In this paper we assess landscape changes occurred in the Diano study area (2651 ha) in the 1954–2000 period and we ascertain land use transition paths and rates of this rural ecosystem. Land use mapping obtained from object-oriented analysis of aerial photographs was used to quantify land use changes between 1954 and 2000. To examine the spatio-temporal patterns of land use change over time, a set of spatial statistics capturing different dimensions of landscape change was identified. An increase of landscape heterogeneity from 1954 to the present was observed due to the expansion of orchards and the fragmentation of field crops. A significant portion (55%) of current orchards surface is represented by former field crops, 24% by vineyards and 15% by forests. The strong expansion of hazelnut orchards concurred to the fragmentation of traditional rural landscape was dominated by vineyards, field crops and forests. Hazelnut orchards expansion was mainly located in places where grapes cultivation was less remunerative. A further expansion of hazelnut in the area should be planned, discussed and carefully monitored through change detection studies in order to avoid potential unsustainable use of the land.  相似文献   
36.
This paper presents an application of the Multi-Scale Integrated Analysis of Societal and Ecosystem Metabolism (MuSIASEM) approach to the analysis of rural land uses. Using secondary data on farming systems in Laos, we illustrate how the concept of metabolic pattern can be used to establish links between the various indicators of performance of rural systems. To this purpose, we characterize the socioeconomic activities in rural Laos by a series of quantitative indicators defined across: (i) different hierarchical levels of organization described at different scales (i.e. households, rural villages, administrative regions and the whole country) and (ii) different dimensions of analysis, including economic, agronomic, social, biophysical, and ecological analysis. The MuSIASEM approach simultaneously employs two non-equivalent criteria for quantification. The observed rural system is described in terms of an integrated set of flow elements (money, food, energy, water, fertilizer and other materials), which are mapped against two distinct fund elements: (i) a multi-level matrix of human activity (flows being expressed in terms of intensity per hour) and (ii) a multi-level matrix of land uses (flows being expressed as density per hectare). Our case study shows that in this way it is possible to move across different hierarchical levels, scales and dimensions, to arrive at an integrated representation of the metabolic pattern of farming systems.  相似文献   
37.
Desertification and land degradation are worldwide problems affecting soil, vegetation and the livelihoods of rural populations. Bowal (plural bowé) is a particular form of degraded land that occurs in tropical regions and leads to the exposure of ferricretes, which are unsuitable for farming. Bowé are more common on farmland and degraded savanna. Changes in land use/land cover were used to map a region of 6.7 million ha in northern Benin, West Africa in 1975, 1990 and 2010. The changes observed during these periods (1975–1990, 1990–2010 and 1975–2010) were used to predict the occurrence of bowé in the period up to 2050 using Markovian chain analysis. The results showed a considerable change in land use/land cover during the three periods. The types of land on which bowé occur (farmland and degraded savanna) increased in northern Benin by 5.4% per year during the period 1975–1990 and 9.5% per year during the periods 1990–2010, while the natural vegetation (forest, woodland and tree savanna) decreased by the same amount. The future scenarios also predicted the same trend. In the period 1975–1990, 1.28 million ha (26%) of natural vegetation was converted to degraded savanna and farmland while 2.23 million ha (53%) of natural vegetation was converted to degraded savanna and farmland in the period 1990–2010. Based on the dynamics recorded during the period 1975–1990 and 1990–2010 respectively, a total of 1.28 million ha (26% of the natural vegetation that was present in 1975) and 1.29 million ha (31% of the natural vegetation that was present in 1990) will be converted to farmland and degraded savanna in the study area by 2050.Thus bowalization will persist and increase in the period up to 2050. The natural vegetation could disappear if protection and restoration measures are not taken. It is thus important to take measures to stop the degradation and to implement programs to restore soils on bowé based on the soil and water conservation techniques used on highly degraded West African soils, such as zaï pit and stone rows with grass strips. Some native plants species adapted to bowalization and resistant to climate change in northern Benin (e.g. Asparagus africanus, Andropogon pseudapricus and Combretum nigricans) should be used in association with soil and water conservation techniques on bowé.  相似文献   
38.
In the complex agro-ecological conditions of Vietnam's northern borderlands, attempts by ethnic minority farmers to create sustainable livelihoods, along with the impacts of state development policies, have direct consequences for land use and land cover (LULC) change. In this paper we analyse the degree to which LULC has changed and diversified from 1999 to 2009 in Lào Cai Province and the underlying relationships with ethnic minority livelihood diversification strategies. We examine the correlation between LULC diversity and various socioeconomic and biophysical proxies using a spatial autoregressive model. Our findings indicate two major changes in LULC: an increase in closed canopy forest and substantial urban growth. LULC diversity increased between 1999 and 2009, suggesting a transition between land uses and/or a diversification of livelihood strategies. Socioeconomic proxies are significant predictors of LULC diversity in both years, while biophysical proxies are only effective predictors in 2009. In-depth interviews regarding state-led policies and ethnic minority livelihoods reveal some of the underlying mechanisms of such LULC transitions and associations.  相似文献   
39.
Soil is a natural resource essential to human welfare by virtue of its numerous crucial functions. In the past, soil has been taken for granted because of its widespread, albeit finite, availability. However, now that world's population is projected to exceed ten billion before the end of this century, soil is increasingly perceived as a precious commodity. Consequently, soil is increasingly under pressure by rich private investors and governments within the poorest countries to satisfy appetites for food production and biofuel. A case study is used to explore the plausibility of soil being considered as ‘brown gold’. Based on the comparison of land use maps, we estimated the value in terms of resource from raw material, carbon sink and virtual calories of the productive soil lost during the period 2003–2008 in the Emilia-Romagna Plain, one of the most productive areas of Italy. More than fifteen thousand hectares of cropland underwent land use change – in particular urbanization – over the 6-year period with an implied loss of crop production potential equivalent to the daily calorific requirement of more than 440,000 people. Taking into account that Italy is no longer self-sufficient in food production, such a loss appears to be strategically significant. Perhaps more importantly, urbanization and soil sealing has had negative ramifications on environmental sustainability, on both local and broad scales, with increased consumption of public funds. A logical framework of the socio-economic impact of land use change has been compiled and is presented as a possible example of a policy relevant approach to managing productive soils as a finite resource.  相似文献   
40.
This paper evaluates the role of trade liberalization and agricultural intensification in mitigating climate change cause and effects on land use and emissions using a computable general equilibrium model. Our results indicate that cropland expansion triggered by climate-induced crop productivity changes results in deforestation and increases emissions in South Asia and globally. Global full trade liberalization on all goods is the optimum policy for South Asia despite significant global deforestation, but for the world, unilateral partial trade liberalization on all goods is a more appropriate policy while ensuring a considerable emissions reduction for South Asia. These results indicate that mitigation responses to climate change are location specific and no one trade policy is suitable at the regional and global levels. Lastly, agricultural intensification by improving productivity growth is the best strategy in land-based emissions mitigation, thereby avoiding the transformation of forest and pasture lands for agricultural cultivation both at regional and global levels.  相似文献   
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