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This paper examines constraints and enabling factors towards ‘integration’ as they are perceived by actors involved in an ongoing strategy development process. The paper examines stakeholder perspectives on current progress in coastal flood risk management in London and the Thames Estuary. The case-study suggests that important steps have been taken towards an integrated and adaptive strategy development process, particularly through the development of informal stakeholder networks. However, constraints in enabling learning within the strategy development process mean that practical pathways of integration in such a large, global-scale city remain challenging to identify and perhaps even more so to implement. 相似文献
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Soils are generally considered to be the result of in situ weathered products of geological substrata. Nevertheless, the Earth's surface is mainly composed of superficial deposits made of sediments reworked during periods of climate instability (glaciation, aridification, flooding, etc.). But to what extent do these deposits influence present‐day soil development and/or lessen the contribution of the geological substratum? In the Swiss Jura Mountains, characterization and distribution of superficial deposits along a toposequence are used in order to decipher the polygenic sources of soil parent materials and question the importance of lithodependence in soil development. The in situ weathering material and the allochtonous deposits are discriminated through analysis of mineralogical composition, grain size distribution of the soil mineral fraction, and multivariate statistical treatment. As expected, calcite is dominant in the autochonous mineral phase, leading to high pH values in deep soil layers. However, the mineralogical composition of the surficial deposits is made of local mineral components mixed with allochtonous aeolian deposits. This exogenous material is dominated by quartz and phyllosilicates, and is reflected by low pH values in soil surficial horizons. The grain size distribution curves of the insoluble residue from bedrocks are unimodal and dominated by fine loam and clays. In contrast, surficial deposits display polymodal curves, demonstrating the contribution of various aeolian episodes and/or sources. Analysis of the surface texture of quartz sand grains shows glacial marks intersected by aeolian shock marks, indicating the posteriority of wind transportation. Loess material originates from Alpine moraines of the Swiss Plateau and is mixed with deposits originating from more proximal Jura moraines, diluting the Alpine signature. Consequently, the soil development does not follow the expected and conventional decalcification process, but is directly influenced by the origin of the primary sediments (even when present only in small amounts) and their evolution. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Amado LL da Rosa CE Leite AM Moraes L Pires WV Pinho GL Martins CM Robaldo RB Nery LE Monserrat JM Bianchini A Martinez PE Geracitano LA 《Marine pollution bulletin》2006,52(2):199-206
Biomarkers of exposure and effect of pollutants were analyzed in croakers Micropogonias furnieri (Teleostei: Sciaenidae) captured in winter and summer in a polluted and in a non-polluted site at the Patos Lagoon estuary (Southern Brazil). Catalase and glutathione S-transferase activities (exposure biomarkers) and lipid peroxidation (effect biomarker) were analyzed in liver samples. Other two effect biomarkers were also studied: blood cells DNA damage (through comet assay and micronucleus test) and respiratory burst measurements. In a broad view, results point to an important seasonal variation of the biochemical biomarkers analyzed. However, data obtained clearly indicate that croakers collected in winter at the polluted site were subjected to a level of clastogenic agents sufficient to generate irreversible genetic damages (mutations) and impair the fish immune system. 相似文献
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Edmund C. Penning-Rowsell Nick Haigh Sarah Lavery Loraine McFadden 《Natural Hazards》2013,66(3):1383-1404
This paper describes the options appraisal undertaken in the UK within the major TE2100 project to investigate the future of protecting London from flooding from the sea. An economic analysis, within a Benefit-Cost framework complemented by Multi-Criteria Analysis, shows that improving the existing flood defences and, in 2070, constructing a new Thames Barrier downstream from the existing one are the “front runner” options for tackling the increase in flood risk that is anticipated in the future. Both sensitivity and scenario analysis have little effect on option choice. Uncertainties inevitably remain, however, when looking so far ahead, but it is clear that continuing to protect this area from the sea is highly cost-beneficial. Also the very high standard of protection now, and the robustness of the existing flood defence assets, mean that major new interventions will not be needed for some time (i.e. until c. 2070). We therefore have time to monitor the situation, carefully plan measures to maintain and enhance the existing defences, and to seek to restrain the growth of risk in the Estuary and in London through carefully designed and implemented resilience-building flood plain management measures. Rather than having to rush to new engineering works, because we have not anticipated what is needed but are forced to respond hastily to a “crisis” situation, the adaptive approach that is now possible is a key legacy of the TE2100 project. 相似文献
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