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211.
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The influence of climate change on history is discussed in such a way as to take account of recent research while seeking to herald, rather than foreclose, the much more focussed and definitive debates that will become possible by the turn of the century. By then, much more elaborated time series of global climatic change over the last several millennia should be available. The period chosen for examination is the 1000 years or so following the collapse of Roman Europe. During this time, civilization seems to wane, wax and wane again, very much in phase with the climate deteriorating, improving and then deteriorating once more. What this overview high-lights is the great vulnerability to climatic perturbation of societies that are marginally poised for other reasons. In several major respects, the whole of world society will be marginal in the 21st century.  相似文献   
213.
214.
Brown BJ 《Disasters》1977,1(2):145-150
This research is part of an extensive study entitled 'International Disaster Response: The Sahelian Experience', which was made possible by a grant number 1711–520147 of the U.S. Agency for International Development and the U.S. Department of State. The opinions expressed are solely the responsibility of the researcher and do not necessarily represent the views of the organizations studied or the sponsoring institutions.  相似文献   
215.
It is now well established that the traditional practice of urban stormwater management contributes to the degradation of receiving waterways, and this practice was more recently critiqued for facilitating the wastage of a valuable water resource. However, despite significant advances in alternative “integrated urban stormwater management” techniques and processes over the last 20 years, wide-scale implementation has been limited. This problem is indicative of broader institutional impediments that are beyond current concerns of strengthening technological and planning process expertise. Presented here is an analysis of the institutionalization of urban stormwater management across Sydney with the objective of scoping institutional impediments to more sustainable management approaches. The analysis reveals that the inertia with the public administration of urban stormwater inherently privileges and perpetuates traditional stormwater management practices at implementation. This inertia is characterized by historically entrained forms of technocratic institutional power and expertise, values and leadership, and structure and jurisdiction posing significant impediments to change and the realization of integrated urban stormwater management. These insights strongly point to the need for institutional change specifically directed at fostering horizontal integration of the various functions of the existing administrative regime. This would need to be underpinned with capacity-building interventions targeted at enabling a learning culture that values integration and participatory decision making. These insights also provide guideposts for assessing the institutional and capacity development needs for improving urban water management practices in other contexts.  相似文献   
216.
ABSTRACT: The Cheat River of West Virginia is impaired by acid mine drainage (AMD). Fifty‐five of its river segments were placed on the 303(d) list, which required calculations of total maximum daily load (TMDL) to meet the water quality criteria for pH, total iron, aluminum, manganese, and zinc. An existing watershed model was enhanced to simulate AMD as nonpoint source load. The model divided a watershed into a network of catchments and river segments. Each catchment was divided into soil layers, which could contain pyrite, calcite and other minerals. A kinetic expression was used to simulate pyrite oxidation as a function of oxygen in the soil voids. Oxygen in the soil voids was consumed by pyrite oxidation and replenished by earth breathing. The by‐products of pyrite oxidation were calculated according to its mass action equations. Chemical equilibrium was used to account for the speciation of ferrous and ferric irons and precipitation of metal hydroxides. Simulated hydrology and water quality were compared to available data. The USEPA used the calibrated model to calculate the TMDLs in the Cheat River Watershed.  相似文献   
217.
Extreme weather and climate-related events affect human health by causing death, injury, and illness, as well as having large socioeconomic impacts. Climate change has caused changes in extreme event frequency, intensity, and geographic distribution, and will continue to be a driver for change in the future. Some of these events include heat waves, droughts, wildfires, dust storms, flooding rains, coastal flooding, storm surges, and hurricanes. The pathways connecting extreme events to health outcomes and economic losses can be diverse and complex. The difficulty in predicting these relationships comes from the local societal and environmental factors that affect disease burden. More information is needed about the impacts of climate change on public health and economies to effectively plan for and adapt to climate change. This paper describes some of the ways extreme events are changing and provides examples of the potential impacts on human health and infrastructure. It also identifies key research gaps to be addressed to improve the resilience of public health to extreme events in the future.

Implications: Extreme weather and climate events affect human health by causing death, injury, and illness, as well as having large socioeconomic impacts. Climate change has caused changes in extreme event frequency, intensity, and geographic distribution, and will continue to be a driver for change in the future. Some of these events include heat waves, droughts, wildfires, flooding rains, coastal flooding, surges, and hurricanes. The pathways connecting extreme events to health outcomes and economic losses can be diverse and complex. The difficulty in predicting these relationships comes from the local societal and environmental factors that affect disease burden.  相似文献   

218.

Even if climate change mitigation is successful, sea levels will keep rising. With subsidence, relative sea-level rise represents a long-term threat to low-lying deltas. A large part of coastal Bangladesh was analysed using the Delta Dynamic Integrated Emulator Model to determine changes in flood depth, area and population affected given sea-level rise equivalent to global mean temperature rises of 1.5, 2.0 and 3.0 °C with respect to pre-industrial for three ensemble members of a modified A1B scenario. Annual climate variability today (with approximately 1.0 °C of warming) is potentially more important, in terms of coastal impacts, than an additional 0.5 °C warming. In coastal Bangladesh, the average depth of flooding in protected areas is projected to double to between 0.07 and 0.09 m when temperatures are projected at 3.0 °C compared with 1.5 °C. In unprotected areas, the depth of flooding is projected to increase by approximately 50% to 0.21–0.27 m, whilst the average area inundated increases 2.5 times (from 5 to 13% of the region) in the same temperature frame. The greatest area of land flooded is projected in the central and north-east regions. In contrast, lower flood depths, less land area flooded and fewer people are projected in the poldered west of the region. Over multi-centennial timescales, climate change mitigation and controlled sedimentation to maintain relative delta height are key to a delta’s survival. With slow rates of sea-level rise, adaptation remains possible, but further support is required. Monitoring of sea-level rise and subsidence in deltas is recommended, together with improved datasets of elevation.

  相似文献   
219.
Based on the national database of 28,104 water rights (concessions) granted in Colombia, this paper presents an analysis of how the principles of equity and sustainability are reflected in water allocation. Concessions appear to be an exclusionary mechanism since only a minority of small water users have concessions and the distribution of water volumes among those who have them is extremely inequitable. The 2009 Gini coefficient calculated for water concessions granted for agriculture was 0.90 compared with the rural land Gini of 0.88 (both indicators grouping holdings under the same entity). More than half of the Colombian departments have a higher Gini coefficient for water than for land, suggesting that water rights are at least as unequally distributed as land, in one of the most inequitable countries in Latin America. Water allocated to domestic, agriculture and hydropower use indicates a lack of consistency of water allocation criteria across regions. The volumetric and administrative attributes of water allocation in Colombia do not account for environmental flows or the concerns of marginalised groups of society that have limited access to the mechanism. Water allocation as a technical task, with limited transparency and secluded from public scrutiny, does not contribute to the solution of increasing water-related conflicts.  相似文献   
220.
The ethnically diverse high-altitude region of Gilgit-Baltistan, with its complex political history, remains relatively free from the controlling gaze of the central state apparatus of Pakistan. In these extraordinary terrain, where local communities rule the region as the “State by proxy”, informal gemstone mining provides an important supplement to livelihoods. This paper shows that gemstone mining in Gilgit-Baltistan is characterised by customary rules and regulations that are based on collective responsibility, and members follow customary authorities because they are not external to the community. It argues that the very idea of centralised “governance” of mineral resources, used widely in contexts of resource extraction as the panacea, needs to be reconsidered when dealing with the particularities of the context. It draws on the concept of ungovernability to underline the fact that sometimes it may simply be impossible to administer informal mining in the conventional sense of the term. It suggests in conclusion that informal mining, which has a long history in Pakistan and has played an increasing role as a source of rural employment and revenue, needs to be accommodated within the legal framework of mining. More importantly, to govern informal mining of gemstones, the first task would be to consider how things are currently done, understanding and respecting customary laws, and build upon them to incorporate their elements into systems that acknowledge community rights and a more equitable sharing of benefits.  相似文献   
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