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This paper introduces a combined modelling approach using a simple water budget model (THC-model) and a 3D reservoir sedimentation model (MOHID Water) to adapt reservoir operation and visualise their effects on the sediment deposition. By this, an effective combined sediment-water management can be identified under semi-arid conditions for dry, median and wet years. Results are presented for the reservoirs of the Tuyamuyun Hydro-Complex (THC), which is located in the lower Amu Darya River. The determination of the actual and usable reservoir storage volume shows that siltation will significantly adversely affect the ability of the in-stream Channel Reservoir to regulate seasonal demand for both irrigation and municipal water supply. However, modelling scenarios results confirm the effectiveness of adapted operation rules for the THC reservoirs and show that the operation of large dams could be modified according to a combined sediment-water management. The experience gained during this study emphasizes the fact that the concept of a combined reservoir management of sediments as well as water can be an efficient measure to improve the sustainable long-term use of reservoirs and to contribute towards a safe water supply in water crisis regions.  相似文献   
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This study was conducted to determine the optimal conditions for PAH degradation from highly contaminated attrition sludge (PAC) using a Fenton process or successive permanganate (KMnO4) oxidation and Fenton processes. The following parameters were studied to optimize the Fenton oxidation process: the amounts of reactants based on the stoichiometric oxidant demand (SOD), the reactant addition protocol and number of doses, and the solid/liquid ratio (S/L). The results showed that the following conditions were optimum: TS?=?30%, 7.5 times SOD, H2O2/Fe2+ ratio?=?10, and added five times during 60 min, which allowed the degradation of 43% of total 27 PAHs from the PAC. Successive Fenton and KMnO4 oxidation processes were also tested. PAH degradation using a sequential Fenton process followed by KMnO4 oxidation (or KMnO4 followed by Fenton) was higher than for the use of Fenton or KMnO4 treatment alone. Up to 71% of the total 27 PAHs were degraded when using a combination of both processes. It appeared that the sequential treatment is a viable method for the significant degradation of 27 PAHs from PAC (t value?>?2.77).  相似文献   
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Context

Integrated conservation decision-making frameworks that help to design or adjust practices that are cognisant of environmental change and adaptation are urgently needed.

Objective

We demonstrate how a landscape vulnerability framework combining sensitivity, adaptive capacity, and exposure to climate change framed along two main axes of concern can help to identify potential strategies for conservation and adaptation decision-making, using a landscape in Madagascar’s spiny forest as a case-study.

Methods

To apply such a vulnerability landscape assessment, we inferred the sensitivity of habitats using temporal and spatial botanical data-sets, including the use of fossil pollen data and vegetation surveys. For understanding adaptive capacity, we analysed existing spatial maps (reflecting anthropogenic stressors) showing the degree of habitat connectivity, matrix quality and protected area coverage for the different habitats in the landscape. Lastly, for understanding exposures, we used climate change predictions in Madagascar, together with a digital elevation model.

Results

The fossil pollen data showed how sensitive arid-adapted species were to past climate changes, especially the conditions between 1000 and 500 cal yr BP. The spatial analysis then helped locate habitats on the two-dimensional axes of concern integrating sensitivity, adaptive capacity and climate change exposure. By identifying resistant, resilient, susceptible, and sensitive habitats to climate change in the landscape under study, we identify very different approaches to integrate conservation and adaptation strategies in contrasting habitats.

Conclusion

This framework, illustrated through a case study, provides easy guidance for identifying potential integrated conservation and adaptation strategies, taking into account aspects of climate vulnerability and conservation capacity.
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Tropical Animal Health and Production - Theileria annulata infection (tropical theileriosis) is a disease of serious economic importance in Morocco. Epidemiological and vaccination studies have...  相似文献   
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以叶尔羌河平原绿洲为研究区,选择1991年、2005年、2016年Landsat遥感影像数据,利用RS和GIS技术对研究区的土地利用进行了定量的提取和分析,同时,通过近26a社会经济数据,采用压力–状态–响应(PSR)模型构建了研究区土地生态安全评价指标体系,并利用熵值法确定了各指标权重,运用综合指数评价法从时间尺度上对1991—2016年26a间研究区土地生态安全水平进行了综合评价。结果表明:①1991—2016年除耕地、建设用地面积增加外,研究区其他地类面积均减小,林地面积减少最大为47.12%。②近26a研究区土地生态安全综合指数大致呈现递增趋势,其中,1991—2007年均处于风险级,2008—2016年土地生态环境有所改善,但安全等级处于敏感级,土地生态环境仍较差。③改善研究区土地生态安全状况,需要加大资金投入力度,促进生态建设,加强土地利用监督管理,控制人口增长,缓解人地矛盾,为实现土地生态安全的可持续发展奠定良好的基础。  相似文献   
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In Tunisia, on‐site co‐composting of oil mill waste would overcome environmental issues and valorize renewable resources. The authors' goal was to determine the physic‐chemical and microbiological properties and nutrient supply characteristics of mixed oil mill waste and green waste compost. Two piles of the same raw materials (2/3 oil mill waste–1/3 green waste, w/w) were moistened with two kinds of water: treated urban wastewater (A1) and tap water (A2). Results showed the following: (i) produced compost decreased in C/N from 32 to 12.30?±?0.89 (A1) and 11?±?0.89 (A2); (ii) major elements (P and K) were within acceptable limits; (iii) A1 and A2 had potentially lower heavy metal contents than the limits established by the second draft of the Biological Treatment of Biowaste of the European Commission and microbial load values below the limit N FU 44‐051 values; (iv) A1 and A2 had, respectively, 93 and 89.67% as germination index Gl values, which confirmed the composts' maturity and safety; (v) for both composts, A1 and A2, culture potting made up of half compost and half soil revealed the highest bean leaves' number; and (vi) the less richness in minerals and organic compounds of A2 compared to A1 gave better germination results for white wheat and bean leaves' number for A2. Even moistened with treated urban waste water, oil mill wastes proved to be very interesting for co‐composting with green waste.  相似文献   
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