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111.
岩溶峰丛洼地水土漏失及防治研究 总被引:19,自引:0,他引:19
中国地质科学院岩溶地质研究所岩溶生态研究团队在国家科技支撑计划和广西科技攻关项目联合资助下,自21世纪以来一直从事西南岩溶山区水土漏失创新性研究。2013年取得了一系列进展,阐明了水土漏失的概念、过程和数学模型;运用野外监测和先进的同位素技术,首次系统揭示了岩溶峰丛洼地不同地貌部位和不同生态环境的水土漏失定量差异和原因,建立了适宜岩溶区特点的水土流失强度分级标准和土壤侵蚀回归模型,创建了生物措施与工程措施有机结合的岩溶峰丛洼地水土保持模式和技术规程,开辟了岩溶石漠化环境生态效益与经济效益俱佳的火龙果生态产业,为西南岩溶地区石漠化综合治理和水土保持提供了技术支撑和示范样板。 相似文献
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退化山地生态系统植被恢复水文效应的SWAT模拟 总被引:2,自引:0,他引:2
植被恢复是改善退化生态环境的重要途径.位于闽东南沿海的晋江西溪流域是我国南方典型的水土流失区.应用基于SWAT的晋江西溪流域产流产沙分布式模型,结合流域内退化生态系统重建要求设定不同植被恢复情景,模拟分析植被恢复下的水文效应.模拟结果表明:SWAT模型能较好的用于流域退化生态系统重建的水文模拟;研究区内,还林比还草更有利于流域的水土保持和生态重建,植被恢复对流域产沙量的影响大于产流量. 相似文献
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Although there is much evidence of intense soil erosion in cultivated areas of Navarre (Spain), scarce information currently is available regarding soil loss rates, the spatial and temporal distribution of erosion, and the factors controlling these processes. Rills and ephemeral gullies are frequently responsible for a high percentage of total soil erosion, and these features can be considered a good approximation for the minimum erosion rates. With the main purpose of determining the annual soil loss rates in cultivated areas of Central Navarre, a detailed assessment of rainfall and rill and gully erosion was made in 19 small watersheds cultivated with winter grains or vineyards. The study period spanned from 1995 to 2001. For cereal watersheds, soil losses were caused by only one or two rainfall events each year. High erosion rates were observed (0.20-11.50 kg/m^2 per year). In vineyards, soil losses were caused by several rainfall events each year, occurring year round. High erosion rates were observed in these vineyards (0.33 y 16.19 kg/m^2 per year). No erosion was observed in those cultivated watersheds with no-till practices. It can be concluded that rill and ephemeral gully erosion can be very significant in Mediterranean regions, and much more attention should be paid to the problem. 相似文献
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Numerical simulation of the critical scale of oasis maintenance and development in the arid regions of Northwest China 总被引:3,自引:0,他引:3
Oasis is a special geographic landscape among the vast desert/Gobi in Northwest China (NWC). The surface sensitive heat flux and latent heat flux at Zhangye Oasis during 1 to 11 August 1991 are simulated using the NCAR nonhydrostatic mesoscale model MM5 Version 3. The horizontal grid resolution is set as 1km. By comparing the simulation results with HEIFE observations, it is proved that the model can be used to simulate the surface energy and water mass exchange of arid and semiarid regions in NWC.Based on the above results, the influence of different oasis scales on the local atmospheric field near the ground surface, and the critical scale of oasis maintenance, in NWC are studied dynamically. The following conclusion is obtained: the local thermal circulation between the oasis and the desert/Gobi is formed in the oasis downstream if the oasis scale is larger than 4 km. This local thermal circulation between the oasis and the desert adjacent to the oasis helps to conserve water vapor over the oasis. At the sametime, it transfers the abundant water vapor from the oasis into the desert/Gobi near to the oasis to supply relatively plentiful water vapor for desert crops to grow on the fringe of the oasis. So, it is advantageous for oasis extension. However, if the scale of the oasis is smaller than 4 km, it is not easy for the local thermal circulation between the oasis and the desert/Gobi to take shape. This study provides a new standpoint for oasis maintenance and development. 相似文献
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宛甸县处于新构造运动强烈上升区,境内峰峦叠嶂,山势陡峻,沟深谷狭,暴雨频繁地质环境十分脆弱,加之森林大量砍伐,陡坡开荒严重,垦植指数过高,超载养蚕放牧,滥采乱挖猖獗,使生态环境遭到严重破坏,水土流换程度日益加剧,严重的水土人,导致水库淤积,河道堵塞,土层变薄,地力下降,洪水泛滥,灾害频繁,给国民经济和社会发展造成巨大损失,本文阐述了宽甸山区水土流失的形成因素和危害现状,并因地制宜提出了水土流失灾害的防治对策。 相似文献