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181.
ABSTRACT

Since the 1990s, climate change impact discourse has highlighted potential for large scale violent conflicts. However, the role of climate stresses on local conflicts over natural resources, the role of policies and adaptation in these conflicts, and opportunities to enhance cooperation have been neglected. These gaps are addressed in this paper using evidence from participatory action research on 79 cases of local collective action over natural resources that experience conflicts in Bangladesh and Nepal. Climate trends and stresses contributed to just under half of these conflict cases. Nine factors that enable greater cooperation and transformation of conflict are identified. Participatory dialogue and negotiation processes, while not sufficient, changed understanding, attitudes and positions of actors. Many of the communities innovated physical measures to overcome natural resource constraints, underlying conflict, and/or institutional reforms. These changes were informed by improving understanding of resource limitations and indigenous knowledge. Learning networks among community organizations encouraged collective action by sharing successes and creating peer pressure. Incentives for cooperation were important. For example, when community organizations formally permitted excluded traditional resource users to access resources, those actors complied with rules and paid towards management costs. However, elites were able to use policy gaps to capture resources with changed characteristics due to climate change. In most of the cases where conflict persisted, power, policy and institutional barriers prevented community-based organizations from taking up potential adaptations and innovations. Policy frameworks recognizing collective action and supporting flexible innovation in governance and adaptation would enable wider transformation of natural resource conflicts into cooperation.

Key policy insights
  • Climate stresses, policy gaps and interventions can all worsen local natural resource conflicts.

  • Sectoral knowledge and technical approaches to adaptation are open to elite capture and can foster conflicts.

  • Many local natural resource conflicts can be resolved but this requires an enabling environment for participatory dialogue, external facilitation, flexible responses to context, and recognition of disadvantaged stakeholder interests.

  • Transforming conflict to greater cooperation mostly involves social and institutional changes, so adaptation policies should focus less on physical works and more on enabling factors such as negotiation, local institutions, knowledge, and incentives.

  相似文献   
182.
阿尔金断裂带对青藏高原北部生长、隆升的制约   总被引:62,自引:3,他引:59  
大量的同位素年代学证据表明(古)阿尔金断裂带可能形成于三叠纪,后又经历了侏罗纪、白垩纪的强烈左旋走滑活动,自印度板块与欧亚大陆碰撞后阿尔金断裂再次活动。主要的走滑活动发生在:(1)245~220Ma;(2)180~140Ma;(3)120~100Ma;(4)90~80Ma;(5)60~45Ma;(6)渐新世至中新世;(7)上新世至更新世以及(8)全新世。沿阿尔金断裂带,伴随左旋走滑活动形成一系列的逆冲断裂和正断裂,反映走滑过程中伴随隆升作用的存在,并且形成自北向南包括祁连山、大雪山、党河南山、柴北缘山、祁漫塔格山和昆仑山,表明阿尔金断裂带制约着青藏高原北部的生长和隆升。阿尔金断裂带东、西两端的白垩纪和新生代火山活动是断裂走滑活动的响应。  相似文献   
183.
一种新型双磙子FPS隔振系统的动力学模型   总被引:1,自引:1,他引:0  
本文基于多体动力学理论建立了一种新型双磙子FPS(Friction Pendu lum System)隔振系统动力学模型。在对该系统进行运动学分析的基础上,可将它归结为一个单自由度系统。应用非惯性系中质点系相对动能定理的微分形式可推导出该系统的运动微分方程,它是一个非线性方程。在小角位移的情形下,可近似得到相应的无阻尼线性系统的固有频率,它与观测结果吻合。这一双磙子FPS隔振系统的动力学方程的建立有助于对该系统动力学行为的研究,对方程的直接求解可提高仿真设计中正问题计算的效率,为设计包含该系统的半主动控制奠定了基础。  相似文献   
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185.
186.
We present a detailed review of the petrological and geochemical aspects of rhyolite and associated silicic volcanic rocks(up to 20 vol%of all rocks)reported to date from twelve well known Phanerozoic continental mafic Large Igneous Provinces(LIPs).These typically spread over<104 km^2(rarely 105 km^2 for Parana-Etendeka)area and comprise<10~4 km^3 of extrusive silicic rocks,erupted either during or after the main basaltic eruption within<5 Myr,with some eruption(s)continuing for≤30 Myr.These rhyolites and associated silicic volcanic rocks(60-81 wt.%of SiO2)are mostly metaluminous to peraluminous and are formed via(ⅰ)fractional crystallization of parental mafic magma with negligible crustal contamination,and(ⅱ)melting of continental crust or assimilation and fractional crystallization(AFC)of mafic magma with significant crustal contribution.Rhyolites formed by extensive fractional crystallization are characterized by the presence of clinopyroxene phenocrysts,exhibit steep negative slopes in bivariate major oxides plots and weak to no Nb-Ta anomaly;these typically have temperature>900℃.Rhyolites formed by significant crustal contribution are characterized by strong negative Nb-Ta anomalies,absence of clinopyroxene phenocrysts,and are likely to have a magma temperature<900℃.Geochemical signatures suggest rhyolite melt generation in the plagioclase stability field with a minor fraction originating from lower crustal depths.A large part of the compositional variability in rhyolites,particularly the SrNd-Pb-O isotope ratios,suggests a significant role of continental crust(upper crustal melting or AFC)in the evolution of these silicic rocks in the continental mafic LIPs.  相似文献   
187.
188.
Magnesium‐rich spinel assemblages occur in the two lunar vitric breccia meteorites—Dhofar (Dho) 1528 and Graves Nunataks (GRA) 06157. Dho 1528 contains up to ~0.7 mm cumulate Mg‐rich spinel crystals associated with Mg‐rich olivine, Mg‐ and Al‐rich pyroxene, plagioclase, and rare cordierite. Using thermodynamic calculations of these mineral assemblages, we constrain equilibration depths and discuss an origin of these lithologies in the upper mantle of the Moon. In contrast, small, 10 to 20 μm spinel phenocryst assemblages in glassy melt rock clasts in Dho 1528 and GRA 06157 formed from the impact melting of Mg‐rich rocks. Some of these spinel phenocrysts match compositional constraints for spinel associated with “pink spinel anorthosites” inferred from remote sensing data. However, such spinel phenocrysts in meteorites and Apollo samples are typically associated with significant amounts of olivine ± pyroxene that exceed the compositional constraints for pink spinel anorthosites. We conclude that the remotely sensed “pink spinel anorthosites” have not been observed in the collections of lunar rocks. Moreover, we discuss impact‐excavation scenarios for the spinel‐bearing assemblages in Dhofar 1528 and compare the bulk rock composition of Dho 1528 to strikingly similar compositions of Luna 20 samples that contain ejecta from the Crisium impact basin.  相似文献   
189.
With concerns mounting over the UK’s energy future and the effects of climate change, it will soon become paramount that all viable sources of renewable energy are fully exploited. This study has examined the scope for reliable and fully predictable tidal electricity generation from the conjunctive operation of 5 major estuary barrages on the West Coast of the UK in an attempt to establish the potential scale of the extractable resources. Two levels of investigation have been undertaken: simple 0-D (‘two-tank’) modelling of barrage energy generation under different operational modes, using the hydraulic characteristics of turbine performance; and 2-D modelling of tidal hydrodynamics over a wide sea area in a computational grid incorporating the barrages with turbines and sluices. It has been demonstrated that more than 33TWh per year of electricity should be attainable, from 22GW of installed capacity, this representing close to 10% of present UK demand.  相似文献   
190.
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