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81.
Abstract

Landscape stewardship is considered an important place-based approach to addressing sustainability challenges. Working at landscape-level requires collaboration between diverse landscape stakeholders. In this study, we partnered with local stewardship practitioners across six cases in South Africa to investigate how they facilitate collaboration towards social-ecological sustainability outcomes. We found that practitioners facilitate collaboration among stakeholders by operating as relational hubs in the landscape. Through these hubs, they build new inter-personal relationships among stakeholders, creating social networks which enable stewardship practice. The hubs deepen human-nature relationships by creating enabling conditions for stewards to put stewardship ethics into action. Drawing on insights from these cases, we call for a relational approach to landscape stewardship which focuses on human-to-human and human-to-nature relationships. Moreover, we argue that landscape stewardship initiatives need to re-focus stewardship on stewards, recognizing them as key agents of change in addressing the conflict between agriculture and conservation inherent in many landscapes.  相似文献   
82.
An overview is given about up-to-date techniques for slope stability and deformation analysis as well as mass flow phenomena simulation.The paper concentrates on a few aspects in respect to the use of numerical modeling techniques,especially in relation to the shear strength reduction techniques,discontinuum modeling,probabilistic concepts,the combination of GIS and numerical modeling as well as sophisticated hydro-mechanical coupling with time-dependent material behavior.At present these topics are preferred topics of scientific and technical research.  相似文献   
83.
随着科技的不断进步,跨文化交际日益频繁,如何在外语教学中培养学习者的跨文化意识已成为外语教育者研究的新课题。试从文化的核心——价值观入手,以文化语言融合教学观为理论基础,提出价值观与语言相融合的文化教学新模式,以期培养学习者的跨文化意识。  相似文献   
84.
随着中国崛起,世界主要大国将战略中心转移至亚洲并通过各种经济组织和经济联盟等经济途径重塑中国周边环境,由此导致中国周边地缘环境形势变得极其复杂。中国则通过共建“一带一路”、亚洲基础设施投资银行、金砖国家开发银行等经济途径化解。本文按照全球—区域—国家间的尺度,探讨了国际经济组织、经济联盟和国家间经济相互依赖等3种主要经济途径对地缘政治格局的影响机制及空间表现。结果表明:通过国家间经济依赖的不对称性改变各国权力大小,进而影响地缘格局中地缘体的权力分配,其空间表现主要为影响地区冲突和改变国家地缘空间影响范围。而国际经济组织和经济联盟则通过权力再平衡影响地缘政治格局,其空间表现主要为数量增长、交错分布和空间范围扩大。中国学者对如何通过经济途径增强地缘政治影响力、改善中国地缘环境的研究不够充分。中国作为崛起中的大国,应更为关注经济实力的增强对周边乃至世界地缘政治格局的影响。为此,应加强以下几个方面研究:①将经济相互依赖转化成为有效的地缘影响力;②利用国际经济组织和经济联盟拓展中国地缘政治空间;③“一带一路”空间走向及沿线国家;④多尺度经济途径影响效应分析;⑤运用定量模拟方法探求国家地缘影响力演变的影响因素以及驱动机制等,为中国的地缘战略提供理论支撑和研究实证。  相似文献   
85.
由于《巴厘行动计划》中明确提出"合作的行业方法"以及发达国家的积极推动,所谓国际行业减排方法正受到越来越多的关注。在对此类方法的定义、分类和提出背景进行简要介绍的基础上,总结了该类方法的最新进展和发展动向。最后对近期发展的特点进行了归纳与评述,指出了发展中国家尤其是我国在国家和行业发展层面所面临的挑战和亟待解决的问题。  相似文献   
86.
Translating ecosystem indicators into decision criteria   总被引:3,自引:1,他引:3  
  相似文献   
87.
The climatology of intense winter cyclone events in the eastern North Atlantic responsible for high magnitude surge generation (top 1% of events) within the region of the South-Western Approaches to northwest France and southwest England is extracted from daily sea-level and 500-hPa level atmospheric pressure analyses. Cluster analysis yields discrete cyclone track regimes linked to upper airflow patterns being responsible for the generation of intense storms (central pressure at sea-level ≤990 hPa) which promote severe surge events ≥60 cm along the French coast of the South-Western Approaches. Fluctuations in storminess are strongly influenced by the southward intrusion and strengthening of the jet stream in mid-Atlantic. These occurrences are often associated with negative sea surface temperature (SST) anomalies near Newfoundland and a strengthening of the thermal gradient across the Atlantic well to the south of its normal position. Resultant cyclogenesis promotes storms displaying a delay in minimum central pressure attainment until well east of 14°W, encouraging enhancement of surge flow. Stepwise multiple regression analysis indicates that the most influential variables in promoting severe surge events in the South-Western Approaches are trans-Atlantic sea surface temperature gradients. The most important influence is the prevailing west–east sea surface temperature gradient during the month of the storm, followed by that for the prior month of the storm and thirdly, the north–south sea surface temperature gradient prevailing during the month of the event. Other influential variables reflect the character of the cyclone, storm duration, mean deepening rate of storm central pressure, the value of the outermost closed isobar around the storm centre, and the longitudinal position of the outermost closed isobar to the right of the cyclone track. In contrast, the North Atlantic Oscillation (NAO) is not very effective as a discriminator of surge activity. This may reflect the greater intra-month volatility of parameters used to derive the NAO index than of other monthly variables considered in the study. The lack of resolvability at the individual storm level probably also arises because of the monthly detailing of the NAO against storms of 2–3 days duration. This behavioural model of extreme storminess in the South-Western Approaches to northwest France provides the basis by which extremes of coastal susceptibility can be calibrated.  相似文献   
88.
Estimation of seismic hazard for the fast developing coastal area of Pakistan is carried out using deterministic and probabilistic approaches. On the basis of seismotectonics and geology, eleven faults are recognized in five seismic provinces as potential hazard sources. Maximum magnitude potential for each of these sources is calculated. Peak ground acceleration (PGA) values at the seven coastal cities due to the maximum credible earthquake on the relevant source are also obtained. Cities of Gwadar and Ormara with acceleration values of 0.21g and 0.25g respec-tively fall in the high seismic risk area. Cities of Turbat and Karachi lie in low seismic risk area with acceleration values of less than 0.1g. The Probabilistic PGA maps with contour interval of 0.05g for 50 and 100 years return period with 90% probability of non-exceedance are also compiled.  相似文献   
89.
降尺度技术在月降水预报中的应用   总被引:33,自引:11,他引:33       下载免费PDF全文
着重介绍月动力延伸数值预报模拟技巧较高的大气环流在局域降水方面的降尺度(downscaling)应用。克服动力降尺度和统计降尺度技术的缺点,从动力与统计相结合的角度,给出月尺度大气环流与局地降水之间的关系,该联系有清楚的动力学背景和天气学意义。120个月的历史实况资料回报试验证明了该关系的合理性。T63/NCC月动力延伸形势场集合预报进行中国降水的降尺度应用亦取得了较好的结果。  相似文献   
90.
Climate variability acutely affects rural livelihoods and agricultural productivity, yet it is just one of many stresses that vulnerable rural households have to cope with. A livelihood approach is used to assess the potential role that seasonal climate forecasts might play in increasing adaptive capacity in response to climate variability, using Lesotho as a case study. An examination of the assets and strategies that rural households employ enables a holistic assessment of the impact seasonal forecasts could have on rural livelihoods. This research thereby bridges macro-level variability with local-level impacts and adaptation to provide insight into the dynamics of forecast use and impact among vulnerable groups.  相似文献   
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