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91.
This case study on the Borkena wetlands in north‐eastern Ethiopia tells, through the voices of the inhabitants, the story of the occupation and management of an area where agro‐pastoralists (Urrane) and farmers have progressively settled. It shows how different policy changes and natural disasters have transformed the type of peoples' livelihoods and land use patterns in the wetland. It tells the history of relationships between smallholder peasants, irrigation farmers, commercial farms, and the Urrane, where conflicts as well as collaboration developed, and it shows how different stakeholders behave and consider their own situation. The study also reveals that development intervention by World Vision Ethiopia (WVE) had mixed impact on peoples' livelihoods in the wetland: sedentary peasants have benefited while the Urrane have been adversely affected. The main issue is the marginalization of pastoralists, with the denial of their traditional land use rights by three successive regimes and administrations. Any solution to the cohabitation of the different groups and livelihoods will have to address the issue of land rights for the pastoralists and promote the fair participation of all stakeholders in the future management of the wetlands. Good governance and the competence of the state actors at local levels are the crucial issues for the realization of the suggested solutions.  相似文献   
92.
Food insecurity and increasing impoverishment of the masses in developing countries constitute a challenge for social scientists, whose theories have tried to catch up with the enormous challenges of diversity, dynamism and the impacts of the forces of­‘glocalisation’. This article reviews the efforts in the social sciences towards understanding food insecurity and suggests a framework incorporating dynamism and diversity in rural communities in the research process. Structural changes affecting peasant economies and peasant responses make existing general theories inappropriate without a contextual treatment. Insights from existing theories are used to construct a livelihood vulnerability framework for researching and understanding food insecurity in rural areas.  相似文献   
93.
This article proposes a shift toward the integrated governance of watersheds as a basis for fostering health, sustainability and social–ecological resilience. The authors suggest that integrated watershed governance is more likely when different perspectives, including health and well-being, are explicitly understood, communicated, and sought as co-benefits of watershed management. A new conceptual device – the watershed governance prism – is introduced in relation to the multiple facets of governance that characterize contemporary water resources management and examined as an integrative framework to link social and environmental concerns with the determinants of health in the watershed context. The authors assess the diagnostic and communicative potential of such a framework, discussing its utility as a concise depiction of multiple, interacting policy priorities and as a guide to integrate different research and policy domains into the governance of water, health and social–ecological systems.  相似文献   
94.
季则舟 《海洋与湖沼》2022,53(4):830-837
对于海岸工程所遇到的自然灾害,仅以加大结构尺度与结构强度的传统方法应对是不可取的。改变传统理念,通过改善工程与环境的关系,提高工程韧性是较合理的选择。韧性海岸工程以工程系统与环境相协调,具有吸收和适应自然力、灾害情况下维持其功能以及灾后可快速恢复的能力为特征。针对港口工程、海岸及港口防护工程建设提出了韧性工程实施策略及方法。以韧性工程理念对港口规划与平面布置、复杂环境下的码头结构及航道工程设计提出优化原则与方案。海岸及港口防护工程可采用多重防护、吸收性防护、变形型防护及生态型防护等类型,以改善工程与环境的适应性,增强工程韧性。  相似文献   
95.
基于乡村弹性的乡村振兴理论认知与路径研究   总被引:13,自引:2,他引:13  
李玉恒  阎佳玉  刘彦随 《地理学报》2019,74(10):2001-2010
在人类社会发展转型过程中出现的乡村衰退问题已成为全球性趋势,亟需实施乡村振兴。科学、系统把握乡村地域系统的演化规律,深入揭示乡村系统与外界发展环境的交互作用模式,提升乡村自身抵御、适应外界环境变化的弹性,是实现乡村振兴与可持续发展的必由之路。本文从乡村弹性视角理论解析了乡村地域系统演化与乡村振兴。研究发现:① 乡村弹性包含乡村系统对外界扰动冲击的抵御能力、适应能力与实现全新发展的转型能力。② 乡村演化分异是乡村地域系统与外界发展主导因素交互作用的结果。在此过程中,乡村弹性决定着不同发展阶段乡村地域系统的演化方式和结果。③ 打造多功能乡村、实施乡村整治工程、培育乡村社会资本对构建弹性乡村起着重要的推动作用。文章强调应科学识别乡村地域系统,差异化制定培育与提升乡村弹性的实施方案,实现乡村系统功能、结构及运行达到均衡状态。  相似文献   
96.
Monitoring coral reef communities at a decadal scale is necessary to understand and project their dynamics to provide a basis for reef management in light of disturbances and climate change. Complementing infrequent and localised in situ observations, time-series of aerial photographs and remotely sensed satellite images provide a means of monitoring the position and extent of reef-top coral communities, vegetation and abiotic substrata at the whole reef scale. The aim of the present study was to map such changes on Saint-Leu Reef (La Réunion) between 1973 and 2007. The period included two cyclones (1989, 2002) and one severe bleaching event (2002). Vertical images of the reef were recorded in five aerial photographs (1973, 1978, 1989, 1997, and 2003) and two Quickbird satellite images (2002, 2006) during that time. Quantitative in situ observations of parts of the reef-top were also available both to document ecological and substratum characteristics that produce the color and texture observable in the photos and satellite images. Coral communities were mapped on all images using manual delineation of polygons identified according to color and texture contrast. The 2006 Quickbird image was used as the mapping base and 15 types of coral communities were identified from a reef survey conducted in 2007. This hierarchical typology used coral growth forms, live and dead coral cover, macro-algae, substratum (sand, rubble and platform) and, to a lesser extent, coral taxonomy. The polygons at date t were over-laid onto image t − 1 across the whole series and their boundaries were manually edited to match the pattern on the earlier image. Labelling of polygons was guided by field-survey data and maps. For coral-dominated patches, six successive pairs of maps from 1973 to 2006 were compared to produce ‘coral community change maps’ for that period. Despite the multiple disturbance events, the coral community distribution and composition in 2006 on Saint-Leu Reef did not display major differences compared to 1973. This suggests a high degree of coral resilience at the site, led by rapid recovery of compact branching corals. The mapping techniques overcame challenges due to different image quality and the sparsity of in situ observations in time and space. Our results demonstrate the potential for further application of reef monitoring protocols based on complementary in situ and remote-sensing data to help understand the dynamics of reef-top coral reef communities and geomorphology over years to decades.  相似文献   
97.
中国区域经济韧性特征与影响因素分析   总被引:2,自引:2,他引:2  
从经济维持性和恢复性2个方面定量化分析中国31省(市)(未包含港澳台数据)应对1997年亚洲金融危机和2008年全球金融危机的经济韧性特征,并对其主要影响因素进行了研究。结果发现:在亚洲金融危机中,西部地区的经济维持性较高,中部地区的经济维持性普遍较低;经济恢复性较高的省市主要集中在中部地区,而东部和西部地区经济恢复性较低,经济维持性和经济恢复性呈现一定的负相关。各省(市)应对全球金融危机的经济维持性普遍较高,经济维持性较低的区域主要分在东部沿海区域和沿长江经济带地区,而经济维持性较高的区域主要集中在西部地区。在亚洲金融危机中,第二产业表现出了较强的经济韧性,而在全球金融危机中第三产业经济韧性较好。影响2次经济危机中韧性能力的主要因素是不同的,区位条件、人均固定资产投资额和人均GDP的解释力较强,但在2次经济周期中的作用方向不同。  相似文献   
98.
童昀  马勇  刘海猛 《地理学报》2020,75(11):2505-2520
新型冠状病毒肺炎(COVID-19)疫情对中国国民经济和社会发展产生剧烈冲击。科学评价中国受新冠疫情短期影响及恢复情况并揭示其时空特征,可为常态化疫情防控阶段的经济形势研判和城市恢复提供有力支撑。基于2020年1月13日—4月8日百度迁徙大数据,通过构建恢复指数(RRI)和恢复缺口(RGI)等指标,从多尺度揭示中国受COVID-19疫情短期影响的逐日特征、阶段特征以及时空格局。结果发现:① 疫情未影响春节前返乡迁徙,节后恢复经历恢复停滞期、快速恢复期、平稳恢复期,全国总体恢复程度由恢复停滞期不足20%上升至快速恢复期末60%左右,3月3日开始进入平稳恢复期,恢复指数达70%以上,完全恢复至历史同期水平仍需较长时间。② 疫情对周末和节假日城市间交往活动影响显著,中部和东北地区尤为明显。③ 疫情影响的区域差异性明显,相对恢复程度西部>东部>中部>东北地区。④ 城市间恢复程度差异显著,节后至4月8日呈现南高北低空间格局。结合疫情程度,广州、深圳、重庆处于高确诊高恢复聚类,河北、天津、黑龙江、河南、安徽、湖南处于低确诊低恢复聚类。⑤ 随着疫情有效控制,城市层面恢复缺口由京津冀、长三角、珠三角等城市群的大规模成片劳动力迁入缺口,转变为国家中心城市和部分省会城市的点状缺口。本文研究结果表明时空大数据在重大突发公共卫生事件实时影响评价方面具有较好应用前景。  相似文献   
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