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151.
Putting climate change policy-integration into practice is challenged by problems of institutional misfit, due to, inter alia, deficient vertical administrative interplay. While most focus within the field of climate change research has targeted the national–local interplay, less is known about the interface of regional and local perspectives. Here, the aim is to study that interface with a specific focus on the relation between regional and local spatial planning actors, through a case-study of transport and coastal zone management in a Swedish municipality. The article is based on interviews (focus group and single in-depth) and official planning documents. The material reveals a tricky planning situation, replete with conflict. In practice, various institutional frameworks, claims and ambitions collide. The attempts to steer the local spatial planning initiatives from the regional level led to conflicts, which in turn seems to have hampered the overall work for climate change management through spatial planning. Furthermore, there are few traces of prospects of a smooth vertical institutional interplay able to support the overall aims related to integrating climate change mitigation and adaptation in spatial planning. 相似文献
152.
Human-driven land-use changes often cause a decline in biodiversity. Although traditional agricultural practices maintained biodiversity at high levels, recent land-use changes may have negative consequences on species composition. In this study, we examined the hypothesis that land consolidation, which is a major recent land-use change in agricultural areas, decreases plant species diversity over the long term (the so-called negative legacy). To test this hypothesis, we examined the relationships between consolidated areas and the occurrence of threatened plant species across Japan and at the prefecture scale. Twenty-three threatened plant species were selected, all of which were formerly common. Our results show that areas containing records of threatened plant species rarely experienced consolidation at whole-country and prefectural scales. Breakdown analysis showed that unconsolidated agricultural areas contained significantly more threatened species than consolidated agricultural areas. These results suggest that threatened plant species require unconsolidated agricultural areas (i.e., these species could not grow in consolidated areas). Thus, we propose that consolidation history could be used as an indicator of the potential for biodiversity recovery. We also suggest that consolidated agricultural areas should be used for food production rather than for the restoration of biodiversity, for reasons of cost efficiency. 相似文献
153.
山东省苹果种植面积的时空演变特征分析 总被引:2,自引:0,他引:2
[目的]利用1978~2015年山东省苹果种植相关数据,实证分析山东省苹果种植面积的时空演变规律及其内在影响因素。[方法]从省域、区域、地市层面分析山东省苹果种植面积的时空演变规律,并运用多元线性回归模型实证分析山东省苹果种植面积变动的具体影响因素。[结果]山东省苹果种植面积从1978年的18.330万hm~2增至2015年的29.968万hm~2,总体增加,并以1995年为拐点先增后减,呈"倒U"形分布。从区域层面看,胶东半岛苹果种植面积稳步增加,泰沂山区、鲁西鲁北平原苹果种植面积持续萎缩,直接导致山东省苹果种植面积的不断减少和苹果主产区向胶东半岛的迁移。从地市层面看,山东省17地市中仅有胶东半岛的烟台、威海两地市苹果种植面积有所增加,其余15地市苹果种植面积均有不同程度的减少。说明山东省苹果主产区呈东进西退、北进南退的变迁特征。[结论]山东省苹果种植面积变动是资源禀赋、种植成本、种植业内部比较效益、种植传统和种植惯性、非农就业机会、非农就业收入、国家政策、地区政策、技术进步等众多因素共同作用的结果。基础设施条件、种植传统和种植惯性、非农就业机会、非农就业收入、地区政策的影响更为显著。其中,种植传统与种植惯性、地区政策对山东省苹果种植面积产生显著正向影响;非农就业机会和非农就业收入产生显著负向影响;基础设施条件向耕地的倾斜也产生显著不利影响。而种植成本、种植比较效益、国家政策、技术进步等因素的影响并不显著。 相似文献
154.
Boru Douthwaite J. Marina Apgar Anne-Maree Schwarz Simon Attwood Sonali Senaratna Sellamuttu Terry Clayton 《国际农业可持续发展杂志》2017,15(3):238-252
There have been repeated calls for a ‘new professionalism’ for carrying out agricultural research for development since the 1990s. At the centre of these calls is a recognition that for agricultural research to support the capacities required to face global patterns of change and their implications on rural livelihoods, requires a more systemic, learning focused and reflexive practice that bridges epistemologies and methodologies. In this paper, we share learning from efforts to mainstream such an approach through a large, multi-partner CGIAR research program working in aquatic agricultural systems. We reflect on four years of implementing research in development (RinD), the program’s approach to the new professionalism. We highlight successes and challenges and describe the key characteristics that define the approach. We conclude it is possible to build a program on a broader approach that embraces multidisciplinarity and engages with stakeholders in social-ecological systems. Our experience also suggests caution is required to ensure there is the time, space and appropriate evaluation methodologies in place to appreciate outcomes different to those to which conventional agricultural research aspires. 相似文献
155.
挠力河流域土地利用变化地形梯度效应分析 总被引:1,自引:0,他引:1
研究目的:探讨地形因素对土地利用格局变化的影响,揭示土地利用时空演变的原因、过程及机理,为区域土地利用规划与管理提供决策支持。研究方法:土地利用信息图谱法、地形位分析法和标准差椭圆分析法。研究结果:(1)各地类在地形梯度上表现出明显的层级分布特征,水田、草地、水域和未利用地的地形梯度优势分布区均为低区段,旱地和建设用地为低、中低区段,林地为中低、中高和高区段;(2)土地利用变化以稳定型和前期变化型为主,二者分布较为分散,稳定型主要为低、中低地形梯度的旱地和中、高地形梯度林地,前期变化型主要为低地形梯度的旱地和中地形梯度的林地二者转变为水田,其余图谱类型的比例均在5%以下,分布较为集中,主要表现为低地形梯度耕地内部结构转变。研究结论:在自然、社会和政策因素综合作用下,挠力河流域土地利用变化地形梯度效应显著,未来应加强对低地形梯度耕地和中、高地形梯度林地的规划管理。 相似文献
156.
Recently, dramatic flood disasters have occurred incrementally in several regions of the world. Land-use change as one of the main affecting factors becomes a key component in flood risk management. This study strives to deal with quantifying how changes in land use to affect the dynamic evolution of flood vulnerability. The floodplains of Wuhan, which are located in the Yangtze River Basin, have been selected as an example. In this paper, we use GIS to gather different historical geometric data as sources of land-use information. By proposing the Simpsons-dominance index and location index to analyze the characteristics of land-use changes, and building a quantitative model to measure flood vulnerability, a series of flood vulnerability maps demonstrate differential flood vulnerability of floodplains of Wuhan in three inundation scenarios and four historical periods. Finally, the non-parametric correlation is used to reveal the interactive effect of land use and flood vulnerability. Based on this study, comprehensive flood disaster management strategies for land-use planning are proposed for government decision-makers to reduce the flood vulnerability of Wuhan in future. 相似文献
157.
158.
基于GIS的云南保山西庄山地流域土地利用变化研究 总被引:4,自引:0,他引:4
对1982,1991,1998年云南保山西庄山地流域土地利用图利用GIS技术进行了处理,分析了土地利用程度变化值和土地利用动态度。结果显示:西庄河流域土地利用以林地为主;林地、灌草地和耕地相互转换最为频繁,年变化率分别为6.94%、4.75%和2.99%;茶园的变化最小;综合土地利用变化动态度为1.91%;在土地利用方式的变化中,国家政策是最强有力的影响因子,相反,人口增长没有直接影响到土地利用变化。 相似文献
159.
基于RS的佛山市土地利用变化的时空特征研究 总被引:3,自引:0,他引:3
李凡 《国土与自然资源研究》2003,(1):51-52
对1988,1999年佛山市两期TM遥感影像数据加以处理。分析了土地利用程度变化值和土地利用动态度。土地利用变化的时空特征表现为近10年来城市用地面积沿主要道路迅速扩展,导致水域,耕地和林地面积大量减少,城市用地矛盾日益突出。 相似文献
160.
Determinants of Residential Land-Use Conversion and Sprawl at the Rural-Urban Fringe 总被引:20,自引:1,他引:20
Carmen Carrión-Flores and Elena G. Irwin 《American journal of agricultural economics》2004,86(4):889-904
We estimate a probit model of residential land conversion using parcel-level data from a rural-urban county in Ohio. Spatial landscape pattern metrics are used to quantify land-use patterns and to link patterns of residential sprawl with factors estimated to influence parcel-level land conversion. Findings indicate that the location of new residential development is influenced by preferences for lower density areas that nonetheless are close to existing urban development. Combined, these forces have generated a moderated pattern of residential sprawl. Spatial error autocorrelation is controlled using a spatial sampling technique that enables consistent estimation of the probit model. 相似文献