Impacts of artificially planted vegetation on the ecological restoration of movable sand dunes in the Mugetan Desert,northeastern Qinghai-Tibet Plateau

摘要

Controlling desertification is an important ecological target for the Qinghai-Tibet Plateau of China,where studies on impacts of vegetation restoration measures on sandy soil improvement are still lacking.The Mugetan Desert in Guinan County,Qinghai Province,northeastern Qinghai-Tibet Plateau is a representative ecological restoration area.The impacts of artificial vegetation on the ecological restoration and its properties are studied by using field investigation and sample testing including contents of the surface layer and the vegetation composition of movable,semi-fixed,and fixed sand dunes.Results demonstrate that the moss crust has formed on the surface of a sand dune which has become fixed after 30 years under the impact of artificial vegetation(i.e.Cathay poplar).Meanwhile,the clay minerals,organic matter,and other soil available nutrients have markedly increased.A correlation has been found between these materials,i.e.,clay minerals and organic matter content increasing with silt and clay increases with reduction in sand content.In addition,soil nutrient were positively correlated with the increase of plant diversity.Under the current meteorological conditions,the artificial vegetation is helpful for the stabilization of sand dune and the ecological restoration in the Mugetan Desert.