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Mendes MP Ribeiro L Nascimento J Condesso de Melo T Stigter TY Buxo A 《Water science and technology》2012,66(10):2162-2169
The Water Framework Directive establishes that the river basin management plans must have a summary of the pressures and impacts of human activities, such as agriculture, on the chemical and quantitative status of groundwater bodies. In order to identify those areas where a potential impact from agricultural activities on groundwater bodies exists, but currently lacking groundwater monitoring data, a methodology was developed that combines the use of gross nitrogen balance values with the results of a specific vulnerability assessment index. A farm management efficiency parameter is added, to identify the factors that contribute to nitrogen use efficiency and to assess the near-future scenarios. This methodology allows the identification of significant pressures that may be responsible for a groundwater body failing good status where there is no representative monitoring network. 相似文献
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FERDINAND SUTTERLÜTY SIGHARD NECKEL 《International journal of urban and regional research》2006,30(4):798-815
This article examines the symbolic order of the relationships between various social groups in disadvantaged neighborhoods and shows that ethnicity is the main reference point of derogatory designations or ‘negative classifications’. Using two districts in German cities as examples, the semantic patterns of mutual negative classifications among autochthonous individuals and their Turkish neighbors are reconstructed. Upwardly mobile individuals of Turkish origin are the most frequent targets of stigmatization. This fact is explained by the existence of a deep symbolic dimension of social inequality that conceives of ethnicity in terms of kinship relations. The socially inclusive or exclusive effects of negative interethnic classifications and the related classification struggles depend on three factors: the internal, i.e. gradual or categorical logic of the classification patterns; the form and process of conflict resolution; and the social contexts in which negative classifications are used. While the disintegrating effects of negative classifications are curbed by institutionalized norms in local politics and economic life, there only exist informal performative norms of interaction in the life‐world, and here these classifications can more easily lead to social exclusion and ethnic separation. 相似文献
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Tibor Y. Stigter Marta Varanda Sofia Bento João Pedro Nunes Rui Hugman 《Water Resources Management》2017,31(2):609-628
A combined assessment of the potential impacts from climate change (CC) and socio-economic development (SED) on water resources is presented for the most important aquifer in the south of Portugal. The goal is to understand how CC and SED affect the currently large pressures from water consuming and contaminating activities, predominantly agriculture. Short-term (2020–2050) and long-term (2070–2100) CC scenarios were developed and used to build aquifer recharge and crop water demand scenarios, using different methods to account for uncertainty. SED scenarios were developed using bottom-up and top-down methods, and discussed at workshops with farmers and institutional stakeholders in the water sector. Groundwater use was quantified for each scenario. Together with the recharge scenarios, these were run through a calibrated groundwater flow model, to study their individual and joint impacts on groundwater levels and discharge rates into a coastal estuary. Recharge scenarios show clear negative long-term trends and short-term increase in temporal variability of recharge, though short-term model uncertainties are higher. SED scenario 1 (SED1), predicting intensification and decline of small farms, considered the most likely by all workshop participants, shows a large drop in agricultural area and water demand. SED2, a most desired scenario by farmers, foresees growth and modernization of agriculture, but proves unsustainable in combination with predicted CC without efficient adaptation measures. The results thus reveal that CC in the region will dynamically interact with economic factors, and going one step beyond, CC could be directly integrated as a constraint in the development of SED scenarios. Exercises involving the integration of CC and SED regionally based scenarios, constructed in both bottom-up and top- down fashion and discussed in participatory contexts are still rarely used for adaptation, and specifically adaptation of agriculture to water scarcity. The joint analysis of CC and SED revealed challenging, as it involved the use of different methods across the border between natural and social sciences. In our view this method contributes in an encouraging manner to a more holistic and transdisciplinary water management, by allowing a more plausible identification of what (and if) adaptation measures are needed. 相似文献
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