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Salles Jean-Michel Teillard Félix Tichit Muriel Zanella Maiko 《Regional Environmental Change》2017,17(5):1455-1465
Regional Environmental Change - The land sparing versus land sharing debate has already had a significant history and was particularly active during the last decade. Studies carried out mostly by... 相似文献
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Two dynamic flux chambers for direct measurement of odorous compound emissions from quiescent liquid surfaces were investigated under simulated conditions in the laboratory. Initially, a flux chamber built according to the model recommended by French standard NF X 43-104 was studied. This chamber was used in two different ways. The first led to a lack of precision concerning emissions rates from the sampled liquid surface, whereas the second led to an overestimation of the measurements. The second part of the study was devoted to an improved dynamic flux chamber, built according to the feedback from the results obtained using the normalised sampling system. Laboratory tests showed good accuracy and precision. This work underlines the importance of the aerodynamic performances of a dynamic sampling system. 相似文献
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In order to better manage artisanal and small-scale gold mining, the Burkinabe authorities have planned to build a suitable methodological support as an aid to elaborating appropriate policies and actions. The developed methodology concerns (a) at a spatial level, the generation and analysis of a geological resources map needed by the artisanal miners and (b) at a socioeconomic level, analysis of the miners' activity. This paper reports and discusses the results of our suggestion to also introduce the use of an approach known as multi-agent system (MAS) as a complementary part of this initial methodology, at a downstage level to the above two analysis stages. MAS methodology could be used to develop simulation models to forecast the future of the activity. MAS is appropriate for describing the dynamics of systems where it is impossible to obtain all output data of a model from a purely mathematical or statistical transformation of input data. Our suggestion involves (i) demonstrating the capacity of the approach to simulate all parameters needed by mining policy makers and (ii) evaluating to what extent the methodology is accepted by them, as well as, at a more scientific level, the literature regarding mining system simulation. 相似文献
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Jean-François Fruget Michel Centofanti Jean-Michel Olivier 《Environmental management》1998,22(1):129-144
/ The part of the Doubs River between Montbeliard and Dole (France), i.e., downstream from the confluence with the Allan River, will be affected by the Rhine- Rhone connection project. In order to improve the understanding of the Doubs ichthyofauna, aquatic environments of the Doubs were sampled by electrofishing. Fish diversity and the presence of some rheophilic species demonstrated the good ecological quality of some stretches of the Doubs. This quality was due to alternating areas with very diversified aquatic environments (riffles, islands and side-arms, backwaters) and a considerable range of flow velocities. The differences in the structure of the fish communities of the different types of aquatic environments were more qualitative (fish species) than quantitative (number of species and number of fish). However, the mean number of fish was statistically lower in the canals (Freycinet canal and channelized part of the Allan River) than in the main course and in the backwaters. The natural parts of the Doubs (unnavigable reaches) showed the most diversified environmental structure and had the most rheophilic fish communities. Thus, the rheophilic species were well represented, but they proved also the most vulnerable to river regulation. However, the most abundant fishes throughout the Doubs River were generalists with no special requirements for food sources or spawning substrate.KEY WORDS: Fish communities; Regulation; Restoration; Floodplain; Large ship canal; Doubs River 相似文献