古尔班通古特沙漠公路扰动带植被恢复研究

Study on the Vegetation Restoration of the Disturbance Belt along the Highways in the Gurbantunggut Desert.

古尔班通古特沙漠区域伴随多条沙漠公路的修筑 ,公路沿线形成了生态扰动带 (包括施工扰动带和运营扰动带 )。它使地表空气流场改变、地表覆被剥离、风沙源出现、地表径流过程受阻、地表水分重新分配以及生境隔离。野外考察和样品分析表明 ,扰动带的植被恢复取决于沙面稳定性、降水的地表分配、时间、地下水位、种源和风场等因素 ,并初步总结出如下规律 :①草方格内部表面沙层的有机质随时间逐渐增多 ;②草方格固沙措施加速了植被恢复的速度 ;③迎风坡自然覆沙 ,种子易于着床和萌发 ;④路肩上形成长营养期的中生植物 ,边坡形成旱生植物 ,路边扰动带内的植被恢复情况因水分条件而变化 ;⑤植被恢复与时间成正比 ,演替过程为 :短命植物、三芒草蒿类梭梭或白梭梭。最后提出改进草方格沙障的材料、增加土壤的有机质含量、使用干水、适时播种等恢复措施。

With the instruction of several highways in the Gurbantunggut desert,there emerged ecological desturbance belt along them including instruction belt and function belt.It changed the atmospheric field near the ground,peeled off the ground cover,brought out sand source,reallocated surface water and isolated the primitive habitat.Field observation and sampling analysis show that the vegetation restoration of the disturbance belt depends on some factors,such as the stability of sand surface,the precipitation distribution on the ground?time?the underground table?seed sources and wind field.At the same time,we primarily conclude the laws of vegetation restoration:①the content of organic matter of surface sand in the checkerboard fence increases by time;②checkerboard fence accelerates the vegetation restoration;③sand covers naturally on the windward slope,seeds tend to germinate and grow;④longitrophic mesophyte vegetation emerges on the road-shoulder,xeromorphic vegetation on both slopes of the roadbed,the restorative condition in the disturbances adjacent to the highway relys on the water condition;⑤the degree of the vegetation restoration increases by time,the process of vegetation succession is:ephemeral plant?Aristida pinnate TrinKobresiaHaloxylon ammodendron or Haloxylon pericum.Finally we put forward a series of restorative measures,such as improving the checkerboard fence material,increasing the content of organic matter of sandy soil,using dry water(water highly absorbing material),seeding timely etc.