四姑娘山国家级自然保护区3种典型植被类型水源涵养功能研究

通过对四姑娘山自然保护区四川红杉林、岷江冷杉林、中国沙棘林3种典型植被类型林下枯落物的实验分析,四姑娘山自然保护区内四川红杉林、岷江冷杉林、中国沙棘林林下枯落物数量、持水能力要高于一般的针叶林和阔叶林,四川红杉林、岷江冷杉林、中国沙棘林林下枯落物最大持水率差异不显著(P=0.080)。LSD多重比较结果可知,中国沙棘林最大持水率显著高于岷江冷杉林、四川红杉林,而岷江冷杉林、四川红杉林间最大持水率差异不显著。     

Effects of the <Emphasis Type="Italic">Astacus astacus</Emphasis> L. Population on Biomass of Macrophytes in a Fresh Water Body

In experiments performed in aquariums, the daily consumption of Chara vulgaris alga by crayfish (Astacus astacus L.) has been determined. These quantitative data have been used to make a prognosis of the effect of the A. astacus population on the biomass of macrophytes in Lake Berezovo (Pskov oblast). The density of the crayfish population and the biomass of higher aquatic vegetation in the lake have been determined in field studies. Extrapolation of the results of laboratory experiments to a natural water body has shown that crayfish are capable of controlling no less than 40% of submersed macrophytes in the area used by their population.__________Translated from Ekologiya, No. 4, 2005, pp. 300–305.Original Russian Text Copyright © 2005 by Kholodkevich, Shumilova, Fedotov, Zhuravlev.     

利用 TM1∶10万卫星图象研究四川富顺——南溪地区土地利用现状及开发途径

土地资源是国家基本资源之一。土地利用状况反映在一个地区土地开垦的指数、土地利用方向、土壤类型、水土流失、植被及覆盖面积、水体类型及覆盖面积等方面,而各种土壤、植被和水体,对日光或不同波长电磁波,有不同的反射、透射和发射特征,在卫片上表现为不同的信息。利用 TM 图象,可区分地表各种土壤、植被和水体的分布,掌握一个地区土地利用现状,制定正确的开发途径。     

城市化对新疆绿洲生态环境的影响与对策

随着西部大开发的不断深入。新疆的城市化进程不断加快，城市化水平不断提高；但是，随着新疆城市化的快速发展，新疆城市所处的绿洲区域的资源、环境、生态也将面临前所未有的巨大压力。城市化正在或即将对绿洲生态环境造成现实的破坏和潜在的威胁。因此正确认识城市化给绿洲生态环境所带来的影响，并在此基础上提出消除不利影响的对策。合理规划和发展绿洲城市是关系到新疆绿洲可持续发展的重要问题。     

Who is in the Lower Reaches, Who Suffers Disasters？ Take Minqin County, a Disappearing Oasis as a Case

Minqin Oasis is located in the lower reaches of the Shiyanghe River Basin, northeast of the Heixi Corridor, at the middle of the Silk Road. Because of the its existence, Badain Jaran Desert and Tengger Desert cannot converge and develop in the south. It has always been an important green barrier to guarantee the eco-security of Hexi Corridor and the Silk Road for thousands of years. But in recent decades, Minqin Oasis is becoming smaller and the desert is becoming larger. Many people, especially the governmental officials in the lower reaches think that the upper and middle reaches have robbed the lower reaches of water resources, and caused insufficient water usage and the deteriorated eco-environment, in the lower reaches, However, the governmental officials in the upper and middle reaches claim that the whole river basin should take the upper and middle reaches as the key regions to develop economy. To address the above argument, we analyze the reasons why Minqin Oasis is disappearing, and find that there are two main factors. One is the quick development of population and economy in the upper and middle reaches; the other is the rapid development of population and economy in the lower reaches. The two factors both have great effect on the water utilization for eco-environment in the lower reaches. So Minqin Oasis is disappearing not only because of the upper and middle reaches but also because of the growth of population and economy itself. The lower reaches should not completely blame the upper and middle reaches. The upper and middle reaches should also pay more attention to the eco-environment in the lower reaches. The whole river basin should develop a harmonious and sustainable relationship among the upper, middle and lower reaches.     

云南省姚安县水土保持生态修复措施的效益研究

姚安县是“长江上中游水土保持生态修复工程”项目县，在该县的洋派河小流域修筑同样面积的4个径流小区，采取不同的生态修复措施，分别为对照地（即撂荒地）、人工补植地（人工种植澳洲金合欢）、封禁措施地、坡耕地（人工耕种的坡耕地）4种，修复中控制人类活动对自然的过度干扰和侵害，充分利用生态自我恢复能力，大面积实施生态自我修复，提高植被覆盖度减少水土流失。从植被重要值，土壤理化性质，土壤的保土保水量以及经济效益等方面进行对比分析计算，研究结果如下：生态修复后人工补植地和封禁地:①植被恢复迅速，植被覆盖度达到60%以上；②土壤的结构得到改善，封禁地全N含量最高，补植地当人工恢复达到一定年限后含N量也会增加；③土壤的保持水土量增加；④生态修复后，经济效益得到明显提高。     

Dynamics of Restoration Processes in the Idle Solonetz Ecosystems in the Southern Transural Region

The initial period of idleness in the solonetz ecosystems of the southern Transural Region is characterized by a significant variability of their soil–plant communities, which is determined by natural periodicity and general direction of the process of ecosystem restoration. Selective consumption of salinizing ions by the plants growing on idle land activates the development of desalinization processes.     

三江源植被保持土壤能力的时空变化

为深入了解三江源区植被保持土壤的能力,以RS和GIS为技术支撑,在对三江源区植被覆盖度动态变化特征分析的基础上,利用SL190—2007《土壤侵蚀分类分级标准》推荐的中国土壤侵蚀模型CSLE(Chinese soil loss equation)估算了2000—2010年三江源区植被的土壤保持能力,并分析其时空动态变化特征. 结果表明:①2000—2010年三江源区年均植被覆盖度为43%~50%;植被平均土壤保持量为849~955 t/km2,并且空间差异很大,总体上呈自西北向东南增加的空间分布格局. ②2000—2010年植被的土壤保持能力呈逐渐增加趋势,其中2000—2005年各流域的土壤保持能力平均增加了约29 t/km2,并以大夏河与洮河流域土壤保持能力的增幅(约700 t/km2)最大,其次为玛曲至龙羊峡(约300 t/km2),羌塘高原区植被的土壤保持能力增幅(仅2.08 t/km2)最小;2005—2010年各流域的土壤保持能力呈现轻微增长,平均增加了约9 t/km2,其中增幅较大的是柴达木盆地东和直门达至石鼓流域(约16 t/km2),增幅最小的是羌塘高原区(仅3.90 t/km2). ③三江源植被土壤保持能力随植被覆盖度的增加呈非线性增长,可通过指数或幂函数形式表达. 研究显示,增加植被覆盖度有助于提高三江源区的土壤保持能力、控制区域土壤侵蚀.