包兰铁路沙坡头地段铁路防沙体系的建立及其效益

沙坡头地段位于腾格里沙漠东南缘,包兰铁路沿线,属草原化荒漠带。在这严酷的条件下不灌溉的人工植物固沙及铁路防护,能否成功成为多年争论的问题。 沙坡头沙漠科学研究站与铁路单位合作30余年;建立了200毫米以下年降水量人工植物固定流沙的典型区;开创了草原化荒漠带治理沙漠的研究站;总结出"以固为主,固阻结合"的铁路防沙体系及措施。为沙区修筑铁路提出了效益显著、易于推广的示范区;成为国际治沙合作和国内外学术交流的基地。

The Establishment and Effect of Protecting System along the Bautou-Lanzhou Railway in Shapotou

Shapotou area,where the Baotou-Lanzhou Railway pass through is situated at the southeast edge of Tengger Desert,belonging to steppe desert zone.Under this harsh condition,whether the establishment of artificial vegetation without irrigation could succeed had been a question,we had studied this problem for many years.In the Shapoton Desert Scientific Research station research work has conducted for more than 30 years and it is proved that the phytoreclamation is entirely possible.The artificial vegetation model has been established,and having been adopted by the Railway Forest Farm,the railway is protected reliably from sand drift. At the first stage of plantation,weused wheat straw to make checkerboard to fix the moving sand dunes.Then planted sand fixator,such as Artemisia ordosica,Hedysarum scoparium,Caragana korshinskii in belts. We plantedSalix gordejevii and Calligonum arborescens on the foot of leeward slopes. After about 10 years the vegetation cover might be reach 30%. Since then if the straw was decayed,repair is no longer needed.After 10 years the water content in sand decreased to 1-2%.On the surface of sand,fine particles were accumulated and a layer of crust was formed.On the sand surface algae and mosses have grown naturally,forming biological crust.After rain,water permeated only within 1 m.The root systems of Hedysarum and Caragana went down deep into more than 4m.So the plants declined and the plant cover decre ased.The natural annual plants and subshrubs regenerated after rain, the natural plant cover may reach 30%,and altogether they formed artificial naturalvegetation complex. We have put forward the design and constructed the model of the railway protecting system,the main point of which is "putting fixation first and combining the fixation with the obstruction" .So that a fixation belt and an obstruction belt were to be constructed. The effect of this System is distinct.It is both feasible and effective. It may be extended as an advanced experience.The effect of obstructing sand drift is markable.In the process of sand-fixation the soil formation is developing and biological species is increased and now the station has become a base of international academic exchanges.