Bioreclamation of sodic waste land—a case study

The study reports a case of bioreclamation of a once barren sodic landscape in the middle part of Gangetic alluvial plain at Banthra Research Station (National Botanical Research Institute, Lucknow, India) (80° 45′ – 53′E and 26° 40′ – 45′N) which began about four decades ago. The investigations were carried out to ascertain the changes in soil characteristics caused by different land‐use systems adopted consistently over three decades. The results showed that the anthropogenic effect on alteration of surface texture through addition of sand in soils of Typic Natrustalfs is still distinct but persistent sodicity is retained. The soils of Inceptic Haplustalfs are markedly improved showing pH value around 8 and ESP > 4 with negligible CaCO₃. The soils of Aeric Endoaquepts supporting stands of forest trees are now devoid of sodicity to about 0\5 m depth, whereas the soils of Aeric Halaquepts though under cultivation have mild sodicity. Soils of Typic Halaquepts occurring on a low physiographic position with aquic soil moisture regime have high sodicity. Summarizing the results of changes in the surface (0 – 15 cm) soil characteristics caused by continuous cultivation irrespective of any crop grown on any soil type reveals that there is perceptible reduction in soil pH and ESP after three decades of reclamation using organic amendments coupled with regular cultivation and afforestation in different locations. Copyright © 2000 John Wiley & Sons, Ltd.     

盐碱地的生态修复研究

随着人口不断增长和社会经济的发展,耕地面积逐步减少,土地质量也在降低,世界范围内土地盐碱化问题越来越严重。为了科学、合理地治理盐碱地,应当以系统论的观点,从盐渍土资源、植物资源、水资源等诸方面综合考虑,把盐碱地作为一种可利用的资源,根据生态恢复学原理,对盐碱地进行生态修复,统筹开发利用与水土保持、经济效益与景观效果之间的关系,努力拓展盐碱地开发利用新途径,积极推进盐碱地资源的生态利用与产业化开发。     

南方水土保持林引种选择

水土保持林能有效的控制水土流失,在福建漳州通过林木引种选择适合该地区立地条件的树种,在此介绍了8种引种比较成功的树种,利用它们的特性,探讨治理水土流失、生态重建的途径。     

冀北山区生态恢复下生态输水现状分析——基于东北沟流域的实证

冀北山区作为京津的水源区对于保障下游的水资源安全发挥着重要作用。以京津水源区东北沟流域为例,基于土地利用调查数据、降雨数据和参与式农户调查获得流域生态环境变化和生态输水的现状,对近年来冀北山区生态环境变化以及这种变化对下游输水的影响进行了研究。结果表明:东北沟流域生态建设已取得了一定的成就,经过二十余年的自然封禁,林地占了流域面积的一半以上,近年来发生土壤侵蚀的频率和强度都明显减少了,这方面的变化是有利于为下游生态输水;但降雨量减少,可利用的水资源减少,森林面积增加,植被对降雨和径流的拦截,下游输水能力下降。加之,水源区的居民生态保护意识不强,没有认识到所处区域的重要地位。大量的化肥投入诱发的面源污染不利于该区域为下游的生态输水,而为上游提供生态补偿可协调上下游的利益冲突。     

滇中高原不同植被恢复条件下土壤肥力和水分特征研究

在干湿不同季节分析滇中高原不同恢复措施下群落的土壤肥力条件和土壤水分条件,结果表明,无论干湿季节,土壤养分含量在不同类型的植被中由优到劣依次为次生常绿阔叶林、针阔混交林、云南松林、桉树林、荒坡灌草丛;各种植被对0～30cm的剖面层次的土壤肥力影响最大,自然恢复更新的植物群落对0～30cm土层的肥力影响显著优于人工林,其变化幅度也高于人工林;自然恢复更新的植物群落在30～60cm、60～90cm土层中,营养物质含量较低,尤其在雨季这些深层土壤营养物质的含量更小。次生常绿阔叶林的持水能力最强,桉树林的持水保水能力最低。次生常绿阔叶林和针阔混交林土壤养分和水分在干湿季节间变化幅度较小,而桉树林和云南松林变化幅度较大。讨论认为雨季补充营养可以显著提高植被恢复的速度,生态建设中尽可能以自然演替恢复更新为主。     

浅谈水土保持生态修复及其在辽东山区的应用

水土保持生态修复是恢复生态学的重要组成部分,是水土流失区退化生态系统恢复的有效途径。它通过利用生态系统自然演替能力,加快生态恢复和水土流失的控制。就水土保持生态修复概念、内涵及需要研究的问题进行讨论,对辽东地区实施水土保持生态修复的适宜性进行分析并提出建议。     

西南岩溶地区的主要生态环境问题及其防治对策

在介绍西南岩溶地区生态环境基本特征的基础上,分析了该地区的主要生态环境问题,并提出了相应的防治对策。认为西南岩溶地区的主要生态环境问题是以石漠化为特征的土地退化,其日益蔓延的主要原因是人类不合理的土地利用,而导致这一结果的根源则是贫困。如何进行植被的恢复重建和实现水土资源的协调利用,是西南岩溶地区环境治理和消除贫困的关键。在部分水土资源短缺、旱涝灾害频繁、环境极度退化的岩溶地区,环境移民是实现生态重建的一条有效途径。     

鼠类危害的环境生态修复探讨

阐述了鼠类危害的环境生态修复的含义和理论发展.应用功能高效、结构和谐、持续控制和经济合理的鼠类危害的环境生态修复原理,从系统论和创新的观点等8个方面论述了害鼠生态调控修复的指导思想.     

Interaction of tree crops with a sodic soil environment: potential for rehabilitation of degraded environments

Tree species of Acacia nilotica, Dalbergia sissoo, Prosopis juliflora and Terminalia arjuna were grown on sodic land for a decade at the Biomass Research Centre, Banthra (of National Botanical Research Institute, Lucknow) India (80°45′–53′E and 26°40′–45′N) with the objective of discovering their relationship with the sodic soil environment to rehabilitate it for maximum fuelwood production. Results showed a marked improvement in biogeochemical characteristics of soil by increasing the water holding capacity (WHC), and by the addition of organic carbon, nutrients and fungal microflora. It was found that D. sissoo and P. juliflora were more efficient than were A. nilotica and T. arjuna in rehabilitating the land. Litter production by the first two was greater than that provided by A. nilotica and T. arjuna, which subsequently caused depletion in soil pH and exchangeable sodium percentage (ESP) values. It was found that there was a greater circulation of Ca, Mg and Fe than the other nutrients by all four tree species, which was a desirable factor. Microbial activity was enhanced due to the accumulation of humus through decomposition of leaf litter and root decay. The potential extent of the biological rejuvenation of the sodic land was related to the distribution of tree roots in the soil profile. To obtain better results a combination of such tree species should be selected in order to provide maximum and constant litter mulch throughout the year. This, in turn, would protect the land from desiccation. Thus, sodic lands could be rehabilitated effectively to restore degraded environments through appropriate mixed tree cropping systems. © 1998 John Wiley & Sons, Ltd.     

黑土区县域生态工程建设对农业景观的调控

近年来, 东北典型黑土区的水土流失问题得到了广泛的关注。该文运用景观生态学的空间分析方法,在地理信息系统GIS支持下,以1989年和2002年陆地资源卫星Landsat TM为主要信息源,结合测绘图件、统计数据及野外调查,分析黑土侵蚀区典型县域(拜泉县)生态恢复与重建的景观结构和水土保持效应。研究结果表明：从1989到2002年,研究区耕地面积下降24731.01 hm²,林草地面积增加了13567.53 hm²,林网进一步完善,水库和塘坝数量由88座增加到1490座。全县55%的水蚀面积得到治理,82.2%的风蚀农田得到林网的防护,43.7%的景观地表超渗径流得到集蓄利用,大于1.5°坡耕地泥沙径流拦截面积增加1420.10 hm²。大规模生态建设下,区域景观类型数量和空间配置发生了较大的变化,景观结构的调整对其水土保持功能起到了很好的调控作用。