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561.
The completion and operation of the Three Gorges Reservoir in China have increased the frequency of geo-hazards and dangers in the area. To monitor and to warn of geo-hazards effectively, the Chinese government has invested billions of funds for constructing a monitoring and warning engineering system. Similar to other social infrastructure investments, a reasonable assessment of investment returns is necessary. Therefore, this study proposes an economic benefit assessment model, which considers both the expected and the actual values. The economic benefit of the geo-hazard monitoring and warning engineering in the Three Gorges Reservoir areas is evaluated. Based on the engineering characteristics, the model reasonably defines the frontier of the input and output and adds the casualties and the losses of ecological environment into the economic benefit evaluation index system. A case study on the Zhangjiawan landslide in Guojiaba Town, Zigui County, was conducted. The evaluation results show that (1) land has the largest benefit in direct reductional loss (total of 56.7 %), while the largest indirect reductional losses of the hazard-bearing bodies are in agricultural production and ecological environment (total of 97.6 %); (2) the costs-to-expected return ratio of landslide monitoring and warning engineering is 1:280, whereas the cost-to-actual benefit ratio is 1:30; (3) the accumulation of relevant information and the public knowledge of geological disasters should be strengthened. 相似文献
562.
针对青海大浪滩盐湖地区钾盐浮选尾矿,研究了尾矿中钾盐的赋存形式,并探索了以稀释老卤为溶剂浸取尾矿中钾的优化条件。结果表明,钾主要以钾石盐矿的形式存在于尾矿中,该矿样属于典型的硫酸镁亚型矿质。同时,考察了不同稀释倍数的老卤的物理性质变化,得到了室温条件下该钾盐浮选尾矿最适宜的浸取条件,老卤/淡水的比例为1∶4,固/液比为3∶2,搅拌反应1 h。在优化条件下,得到了钾离子含量为3.93%的富钾卤水,此时K+浸取率达到86.9%,该卤水进一步蒸发结晶可得到软钾镁矾。本研究为低品位硫酸盐型钾矿的综合开发利用提供了数据支持和参考。 相似文献
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Lv Mingzhu Song Yan Li Xijia Wang Mengsi Qu Ying 《Theoretical and Applied Climatology》2022,147(1-2):737-752
Theoretical and Applied Climatology - As an important parameter of the Earth’s energy budget, the planetary albedo of Earth varies with the dynamics of atmospheric and surface variables. In... 相似文献
566.
Boundary-Layer Meteorology - Surface-layer stability is important in many processes, such as in the surface energy budget, atmospheric pollution, and boundary-layer parametrizations. Most previous... 相似文献
567.
Wenjuan Peng Bin Dong Shuangshuang Zhang Hui Huang Xiaokang Ye Linna Chen Qiang Zhou Jing Wu Cheng Wang Ming Zhu Kangkang Zhao Dian Lv 《Journal of the Indian Society of Remote Sensing》2018,46(11):1795-1803
Shengjin Lake is the only national wetland nature reserve in Anhui Province with rare wintering waterbirds as the main protection object. In recent years, with the strengthening of human activities, the number of rare cranes has changed significantly. Taking the Shengjin Lake natural wetland as an example, this paper studied the response of crane population to land use change, which had important implications for the protection of cranes. This paper analyzed the land use of Shengjin Lake by referring to the eight periods of TM remote sensing images (1986, 1990, 1995, 2000, 2004, 2008, 2011 and 2015) and using ERDAS and ArcGIS tools. The diversity of bird habitats in Shengjin Lake nature reserve was analyzed. Combined with the changes in the number of rare cranes from 1986 to 2015, the impacts of land use and climate change on the cranes in protected areas were analyzed. The results showed that: there was a correlation between the number of cranes land use types and climate changes. The type of land of Shengjin Lake nature reserve was relatively small change in the early years in 1986. It was a relatively large change in the type of land, and the number of cranes had a significantly reducing in 1990s. It until 2000, the number of rare cranes had a slight rebound; however from 2012 to 2015, the number of cranes had dropped again. It had a greater influence on the number of cranes about the change of construction land, reeds mudflats, mudflats, marsh land and paddy fields in the wetland. 相似文献
568.
Chen Jian Zhu Yubo Lv Lei Huang Hairong 《Geotechnical and Geological Engineering》2022,40(6):3211-3224
Geotechnical and Geological Engineering - The fluctuation in reservoir water level is one of the key external factors affecting the stability of slopes. Finite element models are established for... 相似文献
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