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The ecohydrology of the soil-vegetation system restoration in arid zones: a review

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research in cold and arid {3. 2009年第3期1卷 199-206页

作者： XinRong Li 1,2, ZhiShan Zhang 1,2, Lei Huang 1,2, LiChao Liu 1,2, XinPing Wang 1,2 1. Shapotou Desert research and Experiment Station, cold and arid {3. environmental and engineering research institute, chinese Academy of Sciences, lanzhou, Gansu 73.000, china. 2. Laboratory of Stress Ecophysiology and Biotechnology, cold and arid {3. environmental and engineering research In-stitute, chinese Academy of Sciences, lanzhou, Gansu 73.000, china. chinese Acad Sci Cold & Arid Reg Environm & Engn Res Inst Shapotou Desert Res & Expt Stn Lanzhou 730000 Gansu Peoples R China chinese Acad Sci Cold & Arid Reg Environm & Engn Res Inst Lab Stress Ecophysiol & Biotechnol Lanzhou 730000 Gansu Peoples R China

arid zones, which cover approximately 40 percent of the earth’s land surface, support complicated and widely varied ecological systems. As such, arid zones are an important composition of the global terrestrial ecosystem, and water is the key and abiotic lim-ited factor in ecosystem-driven processes in these areas. Ecohydrology is a new cross discipline that provides, in an objective and comprehensive manner, novel ideas and approaches to the evaluation of the interaction and feedback mechanisms involved in the soil–vegetation systems in arid zones. In addition, ecohydrology provides a theoretical basis of ecological restoration that is cen-tered on vegetation construction. In this paper, long-term monitoring and local observations in the transitional belt between a de-sertified steppe and a steppified desert at the Shapotou Desert {3. and Experiment Station, Tengger Desert, in northern china, were evaluated. The primary achievements and related {3. progress regarding ecohydrology in arid zones were analyzed and summarized, as a keystone, and the response of soil ecohydrological processes to the changes in the species composition, structure, and function of sandland vegetation was discussed. Meanwhile, the long-term ecological effects and mechanism of regulation of vegetation on soil habitat and on water-cycling were considered. As a vital participant in the ecohydrological processes of soil–vegetation systems, the studies on biological soil crusts was also summarized, and related theoretical models of restoration based on the water balance was reviewed.

关键词： vegetation regulation by soil moisture ecohydrology process biological soil crust ecological restoration of soil–vegetation systems

科尔沁沙地草地植被恢复演替进程中群落优势种群空间分布格局研究

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生态学杂志 2004年第2期23卷 1-6页

作者：张继义赵哈林中国科学院寒区旱区环境与工程研究所兰州730000

通过对处于流动沙地、半固定沙地和固定沙地等不同恢复演替阶段的群落的取样调查 ,研究了科尔沁沙地草地植被恢复进程中群落优势种群的空间分布格局及其动态变化。运用扩散系数、聚集指数、平均拥挤度、聚块性指数、Green指数、聚集强度... 详细信息

通过对处于流动沙地、半固定沙地和固定沙地等不同恢复演替阶段的群落的取样调查 ,研究了科尔沁沙地草地植被恢复进程中群落优势种群的空间分布格局及其动态变化。运用扩散系数、聚集指数、平均拥挤度、聚块性指数、Green指数、聚集强度、Poisson分布和负二项分布的 χ2 拟合检验等 7项指标 ,对群落优势种群的分布格局的研究结果基本一致 ,大多数物种的空间分布呈显著的聚集分布。在演替进程中种群格局强度的变化和群落总体聚集程度的变化与种群动态和群落结构的空间异质性相对应 ,较高的聚集程度是种群分布斑块化和群落结构的空间异质性的反映 ,随着演替进展 ,优势种的种群数量扩展 ,但种群分布的聚集强度下降 ,群落结构的空间异质性降低。在 7种测定分布格局的指标中 ,聚块性指数、Green指数和聚集强度是无量纲的指标 ,其大小不受种群大小的影响 ,其变化可以较好地指示格局强度本身的变化。

关键词：科尔沁沙地恢复演替草地群落空间格局

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植被(植物群落)稳定性研究评述

生态学杂志 2003年第4期22卷 42-48页

作者：张继义赵哈林中国科学院寒区旱区环境与工程研究所兰州730000

稳定性是植物群落结构与功能的一个综合特征。本文对影响植被稳定性的主要干扰因素、群落多样性 (复杂性 )与稳定性的关系、植被稳定性的判定与测度指标、稳定性的机制等方面的研究进展进行了阐述。指出应加强干扰对植被稳定性影响及提... 详细信息

稳定性是植物群落结构与功能的一个综合特征。本文对影响植被稳定性的主要干扰因素、群落多样性 (复杂性 )与稳定性的关系、植被稳定性的判定与测度指标、稳定性的机制等方面的研究进展进行了阐述。指出应加强干扰对植被稳定性影响及提高干旱区人工植被稳定性的技术措施的的研究 ,以指导自然植被的保护利用和人工植被的建设 ,对植被稳定性机制的认识需要从植物群落内部的生物学生态学过程方面进行深入研究。

关键词：植被稳定性多样性干扰测度指标

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大规模引水隧洞群施工方案三维有限元分析

水力发电学报 2004年第6期23卷 83-87页

作者：张志强李宁徐彬西安理工大学岩土所西安710048

应用奥地利大型岩土工程数值仿真分析软件FINAL[1],对马来西亚BAKUN水电站8条引水隧洞的三种开挖顺序进行了模拟施工过程的三维有限元仿真分析。通过分析,评价了引水隧洞施工期围岩稳定性与支护结构安全性,评价了锚喷结构的支护效果,最... 详细信息

应用奥地利大型岩土工程数值仿真分析软件FINAL[1],对马来西亚BAKUN水电站8条引水隧洞的三种开挖顺序进行了模拟施工过程的三维有限元仿真分析。通过分析,评价了引水隧洞施工期围岩稳定性与支护结构安全性,评价了锚喷结构的支护效果,最终得到了三种方案中最优的开挖顺序,对于类似工程的设计具有指导与借鉴意义。

关键词：水工隧洞开挖顺序有限元分析围岩稳定性大规模

Laboratory test on the combined cooling effect of L-shaped thermosyphons and thermal insulation on high-grade roadway construction in permafrost regions

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research in cold and arid {3. 2009年第4期1卷 307-315页

作者： YuanHong Dong,YuanMing Lai,MingYi Zhang,ShuangYang Li State Key Laboratory of Frozen Soil engineering,cold and arid {3. environmental and engineering research institute,chinese Academy of Sciences,lanzhou,Gansu 73.000,china. State Key Laboratory of Frozen Soil engineering Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences cold and arid regions {3. and engineering research institute Chinese Academy of Sciences

With the completion of the Qinghai-Tibetan Railway,economic development of related areas has been greatly ***,in return,calls for building or upgrading more roadways,especially high-grade *** cold regions,the thawing of permafrost can induce settlement damage of and even failure to railway (or roadway) *** (self-powered refrigera-tion devices that are used to help keep the permafrost cool) have proved effective in mitigating thaw settlement by maintaining the thermal stability of the ***,for high-grade roadway embankments of great width,stabilizing or cooling ef-fects of traditional geotechnological measures may be *** enhance the cooling effect of thermosyphons,an L-shaped thermosyphon was designed.A laboratory test was carried out to study the combined cooling effect of the L-shaped thermosyphon and thermal insulation applying to roadbed *** angle between the evaporator and condenser sections of the L-shaped thermosyphon is 13. degrees,and the L-shaped thermosyphon was inserted into the soil at an angle of 5 degrees with the road *** tested results show that the L-shaped thermosyphon is effective in removing heat from a roadway in *** the ambient air temperature is lower than the soil temperature,the thermosyphon is active and extracts the heat in the soil around *** the ambient air temperature is higher than the soil temperature,the thermosyphon is inactive,and no heat is in-jected into the soil through the L-shaped *** to embankments with straight thermosyphons,the inner parts of the embankments with L-shaped thermosyphons were significantly *** is hoped that the present study would be useful to the application of L-shaped thermosyphons in the construction of high-grade roadways in cold regions.

关键词： L-shaped thermosyphon thermal insulation cooling effect foundation soils high-grade roadway

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干旱地区不同下垫面的辐射收支

太阳能学报 2004年第1期25卷 37-40页

作者：季国良候旭宏吕兰芝李韧中国科学院寒区旱区环境与工程研究所兰州730000

利用2000年6月2001年5月在干旱地区敦煌和高原北部的五道梁所获取的太阳辐射观测资料,分析研究了干旱地区不同下垫面的加辐射收支特点。结果表明:虽然两地地理位置和海拔高度不同,但由于两地下垫面条件的差异,使得太阳短波辐射特别是地... 详细信息

利用2000年6月2001年5月在干旱地区敦煌和高原北部的五道梁所获取的太阳辐射观测资料,分析研究了干旱地区不同下垫面的加辐射收支特点。结果表明:虽然两地地理位置和海拔高度不同,但由于两地下垫面条件的差异,使得太阳短波辐射特别是地表吸收辐射在夏季大致相近,冬季则是敦煌小于五道梁;长波辐射(地面向上长波辐射和大气逆辐射)郭煌明显大于五道梁;地表净辐射夏季五道梁比敦煌为大,冬季则两地相近。

关键词：干旱地区地表吸收辐射地面向上长波辐射大气逆辐射地表净辐射

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我国西部地区耕地退化现状及其防治对策

水土保持学报 2002年第A1期16卷 1-5,10页

作者：李福兴中国科学院寒区旱区环境与工程研究所甘肃兰州730000

从论述耕地在我国西部经济和社会发展中的战略地位和作用入手 ,根据翔实的资料分析了西部地区耕地退化的现状 ,包括耕地水土流失、沙化、土壤盐碱化、土壤养分亏缺和土壤性质恶化、土壤污染、耕地的非农业占用与损毁等诸多方面 ,探讨了... 详细信息

从论述耕地在我国西部经济和社会发展中的战略地位和作用入手 ,根据翔实的资料分析了西部地区耕地退化的现状 ,包括耕地水土流失、沙化、土壤盐碱化、土壤养分亏缺和土壤性质恶化、土壤污染、耕地的非农业占用与损毁等诸多方面 ,探讨了耕地退化的发展趋势 ,并讨论了耕地退化对西部地区经济和社会可持续发展的影响。

关键词：耕地退化防治对策西部地区

Using humic acid for remediation of sandy soils contaminated by heavy metal

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research in cold and arid {3. 2009年第3期1卷 267-276页

作者： YaJun Wang 1, HongLang Xiao 1, JinXi Wang 2, Yong Wang 3.1. Heihe Key Laboratory of Ecohydrology and River Basin Science, cold and arid regions {3. and engineering research institute, chinese Academy of Sciences, lanzhou, Gansu 73.000, china. 2. School of Chemical engineering, Gansu Lian He University, lanzhou, Gansu 73.000, china. 3. Yantai institute of Coastal Zone research for Sustainable Development,chinese Academy of Sciences, Yantai, Shandong 264003. china. Heihe Key Laboratory of Ecohydrology and River Basin Science Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences School of Chemical engineering Gansu Lian He University

This paper presents the development of a new remediation technology for contaminated sandy soil using humic acid (HA). Distribution of amount of Cr (VI) in the aqueous or solid system containing humic acid and sandy soil, was studied using batch experiments, es-pecially for effects of reaction time, pH, concentrations, temperature and irradiation on the reduction of Cr (VI), and the optimum reaction conditions. The results indicated a significant increase of the adsorption of Cr (VI) because of the complexion reaction between HA and Cr (VI) that occurred under acidic condition. The reaction mechanisms of HA with chromium on sand surfaces were certified. Thus it came to a conclusion that HA could be used effectively on remediation of Cr (VI)–contaminated soil and groundwater in a wide range of pH, with or without sunlight. These results suggest that the organic-inorganic complex—such as sandy soils coated with humic substances—is important as a metal reservoir in the environment.

关键词： remediation humic acid hexavalent chromium complexion sandy soil

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渤海和北极海冰组构及晶体结构特征分析

海洋学报 2003年第6期25卷 48-53页

作者：李志军康建成蒲毅彬大连理工大学海岸和近海工程国家重点实验室辽宁大连116024 中国极地研究所上海200129 中国科学院寒区旱区环境工程研究所冻土工程国家重点实验室甘肃兰州730000

渤海一年冰的组构和晶体结构表现出的冰的非连续生长速率使得冰层底部具有气泡含量不同的许多分层;静水生长的灰冰具有典型的粒状冰和柱状冰;融化-重冻结冰和重叠冰具有特定的晶体结构.位于北冰洋72°24 03.′N,153.3..994′W,长2 2m... 详细信息

渤海一年冰的组构和晶体结构表现出的冰的非连续生长速率使得冰层底部具有气泡含量不同的许多分层;静水生长的灰冰具有典型的粒状冰和柱状冰;融化-重冻结冰和重叠冰具有特定的晶体结构.位于北冰洋72°24 03.′N,153.3..994′W,长2 2m的冰心样为三年冰,并且发现其内有一种新的晶体类型,定义为碎屑凝聚冰.由位于北冰洋74°58 614′N,160°3. 83.′W,长4 86m的冰心样的晶体结构分析发现它过去为冰脊,后经融化-冻结改造形成冰丘的证据.

关键词：海冰组构晶体渤海北极