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31.
One of the main issues with the concept of ecosystem services is its absence on the ground in concrete operational decision-making contexts; that is, an implementation gap. In this study, we investigated if this gap could be overcome through the use of open-source data and free tools, and the adoption of a short-term participatory process. We tested these methods in the context of a project in the urban metropolitan area of Bordeaux (Communauté urbaine de Bordeaux: CUB) in France. The ecosystem services were defined using a participatory approach involving local stakeholders, and then selected scenarios were simulated to test the impact of various development or conservation plans. The study addressed three main questions: (1) Is it possible to adopt a simple methodological approach that overcomes the implementation gap through the development of a user-friendly and inclusive method? (2) What is the added value of a participatory approach? (3) With regards to four scenarios in this territory, what are the ES trends in the selected biophysical and monetary indicators, and will knowledge of these trends help planners to shape a sustainable trajectory for the territory? 相似文献
32.
Megaregion has emerged as a new dimension of global urbanization. A megaregion approach based on polycentric strategy is deemed to enhance regional economic competitiveness. Numerous studies have highlighted the economic benefits, celebrated the spill-over effects, and outlined the creative potentials of contemporary megaregion policies in different nations worldwide. However, further policy instruments require the knowledge about the achievement and failure of megaregion policies that seek for spatial, economic, social, and environmental efficiency and sustainability. This paper introduces China’s megaregion policy and proposes an analytical framework for performance evaluation from four principle domains (rational urban growth, economic development, social equity, environmental protection) at three levels (internal collaboration, integral development, and overall development). Using a case of the Megaregion around Hangzhou Bay (MAHB), we find very limited success of China’s megaregion policy. In particular, the megaregion policy only accomplishes the economic goal, and fails to achieve the goals of rational urban growth, environmental protection, and social equity. A series of mechanism based regressions are established and show that the implementation duration of megaregion policy: (1) associates positively with the economic growth; (2) relates negatively to social equity and urban rational growth; and (3) has no significant relationship with improved environmental quality. Institutional fragmentation, no unified spatial planning, and inadequate legislation at megaregional level are the underlying causes of the expected performances within the policy context of governance itself. We finally propose some possible solutions and discuss the implications for spatial polycentric governance. The demonstrated methodological framework can be applicable to other megaregions around the world. This paper is thus believed to provide some new insights for land use policy. 相似文献
33.
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
34.
This study examines the role of tourism development in reducing regional income inequality in China. First, the theoretical foundation for how tourism affects regional income inequality is discussed. Second, based on the conditional convergence framework, this study proposes a spatiotemporal autoregressive model to capture spatial and temporal dependence as well as spatial heterogeneity. Tourism development is introduced as a conditional convergence factor in an attempt to examine whether the convergence speed is accelerated by regional tourism development. Third, the effects of international and domestic tourism in narrowing regional inequality are compared both globally and locally. The empirical results indicate that tourism development contributes significantly to the reduction of regional inequality, with domestic tourism making a greater contribution than international tourism. 相似文献
35.
Land greening in China is regarded as contributing a great deal to greening of the Earth. The phenomenon is mainly attributed to climate change, arising atmospheric CO2 and ‘Grain for Green’ (GFG) land management policies. However, limited knowledge is known how much land greening is from contributions of the GFG practice. Therefore, the study took the typical region of the GFG practice, the Loess Plateau, as the study area, and used 1982–2015 satellite-observed GIMMS3g normalized difference vegetation index (NDVI) data, ERA-Interim climatic variables (precipitation, temperature and solar radiation) and atmospheric CO2 concentration data with the help of a developed TPRC-based NDVI model to derive GFG-induced NDVI after 1999. Furthermore, this study tracked the spatial-temporal dynamics of GFG-induced NDVI and assessed contributions of the GFG practice to regional vegetation changes. Results showed that satellite-observed NDVI and TPRC-based NDVI both exhibited an increasing spatial pattern from the northwestern to southeastern Loess Plateau, but their greening trends were separately 0.0022 and 0.0009 per year in 1982–2015 (p < 0.05). Note that the satellite-observed greening trend was much steeper with a slope of 0.0056 per year after 2006 (p < 0.05). The subsequent analyses documented that GFG-induced land greening were largely responsible for the steep trend. In space, evident greening patterns began to be observed in the central Loess Plateau from 2006 to 2008, afterwards expanded towards eastern and southwestern Loess Plateau. In 2011–2015, the increase magnitude of GFG-induced land greening in the Loess Plateau averagely accounted for 8.5 % in comparison to estimated TPRC-based NDVI, but in six natural zones were various, ranging from 3.2%–15.7%. In some regions of central Loess Plateau, GFG-induced NDVI contributed even more than 20 % to vegetation increase. This study highlights that land use management contributes more to land greening dynamics over the Loess Plateau compared to climate change and arising atmospheric CO2 concentration. These findings likely provide some valuable information for curbing or enhancing specific-location vegetation changes in future regional land management and planning. 相似文献
36.
根据2011-2014年科技部《国家重点科技基础条件资源调查表》以及国家统计年鉴数据,首先,使用赫芬达尔指数定量描述了利用国家重点科技资源进行创新活动的非均衡性。其次,使用网络DEA方法,实证分析了2012-2014年中国(内地)各省份国家重点科技资源对区域创新发展的支撑作用。研究表明,国家重点科技资源对区域创新发展的支撑作用不仅取决于资源创新生产阶段,而且受制于重点科技资源支持下的区域创新发展阶段。重点科技资源的支撑作用还有较大提升空间,70%的省份创新成果转化能力有待提高,且大部分省份的国家重点科技资源未实现优化配置。此外,全国及东部、中部和西部国家重点科技资源对区域创新发展的支撑效率不存在绝对收敛趋势。 相似文献
37.
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
38.
In this study, we analyze the regulation of markets for the provision of services whose costs are subsidized for paternalistic reasons. We model the choice of a benevolent regulator who wants to maximize consumer welfare in a setting where quality cannot be verified and the good provided is fully subsidized. The choice is thus made between two types of providers (profit maximizers and altruistic providers) and two frameworks (monopoly franchise and quality competition). Our analysis shows that in this environment the performance of mixed markets is always dominated by pure forms. Moreover, although making efficient providers compete for the market minimizes cost, the choice of quality competition with altruistic providers may be preferable from a welfare point of view whenever service quality is relevant and the productivity differential is not substantial. 相似文献
39.
The daily trip to work is ubiquitous, yet its characteristics differ widely from person to person and place to place. This is manifested in statistics on mode and distance of travel, which vary depending on a range of factors that operate at different scales. This heterogeneity is problematic for decision makers tasked with encouraging more sustainable commuter patterns. Numerical models, based on real commuting data, have great potential to aid the decision making process. However, we contend that new approaches are needed to advance knowledge about the social and geographical factors that relate to the diversity of commuter patterns, if policies targeted to specific individuals or places are to be effective. To this end, the paper presents a spatial microsimulation approach, which combines individual-level survey data with geographically aggregated census results to tackle the problem. This method overcomes the limitations imposed by the lack of available geocoded micro-data. Further, it allows a range of scales of analysis to be pursued in parallel and provides insights into both the types of area and individual that would benefit most from specific interventions. 相似文献
40.
Spatial modeling of economic phenomena requires the adoption of complex econometric tools, which allow us to deal with important methodological issues, such as spatial dependence, spatial unobserved heterogeneity and nonlinearities. In this paper we describe some recently developed econometric approaches (i.e. Spatial Autoregressive Semiparametric Geoadditive Models), which address the three issues simultaneously. We also illustrate the relative performance of these methods with an application to the case of house prices in the Lucas County. 相似文献