沙漠铁路周边生态环境恢复演化研究

Study on the Ecological Environment Recovery and Evolution around Desert Railway

十一五期间,国家将重点加强中西部铁路建设,到2010年,西部铁路网总规模即达35 000 km。选择位于腾格里沙漠东南缘的包兰铁路中卫至干塘段为研究对象,通过对该段铁路周边生态环境的回访调查与监测,研究分析沙漠铁路对周边生态环境的影响以及恢复演变过程。认为铁路工程建设在施工期对地表植被、沙结皮等原有覆盖层会造成不同程度的破坏,从而加剧风沙活动,但通过采取卵石覆盖、土工网垫、草方格沙障、植树造林等治理措施,能够得到有效控制。人工干预措施中,灌溉造林对沙漠铁路生态环境起到了良好的改善作用,但投资较大;旱生造林也有改善作用,但作用缓慢;沙化严重地区植被自然恢复能力较差,较人工干预条件下的恢复要慢得多。通过治理,铁路周边生态环境已由铁路修建前沙漠化严重的生态背景逐步演化为绿色防护体系格局。这为修建铁路过程中沙漠地区生态环境保护,尤其是沙漠化严重地区的生态恢复与重建提供了参考依据,并对西部大开发战略实施具有重要的实践意义。

In the eleventh five-year plan, the nation will pay much attention for railway construction. By the end of 2010, the general scale of railway network in that area will be 35 000 kin. Taking Baotou-Lanzbeu railway （ Zhongwei-Gantang section） location on southeastern tengger desert as research objects, by callback investigation and monitoring the surrounding environment, the impact induced from railway construction and progress of ecological environment recovery and evolution was analyzed. The results showed that construction had an impact on surface covered layer such as vegetation and sandy crust, which would aggravate aeolian activities, but be controlled by using some engineering measures such as gravel cover, earthwork mesh cushion, straw-checker sand-barrier and afforestation. Among artificial intervention measures, irrigation afforestation is a useful way to improve ecological environmental around railway, but investment is large. On the other hand, the investment of dry-afforestation is small with a slow speed. By governance, the ecological environment turns from serious desert ecological back-ground to green protection pattern. The research conclusions could provide reference for ecological environment protection around railway and ecological restoration and reconstruction in desert region, and has great significance for western development strategy.