关键词: 腾格里沙漠, 固沙植被, 生物多样性, 生态恢复

Abstract: Sand-binding vegetation in Shapotou region at southeastern edge of Tengger Desert began to be planted in 1956. Over the past 46 years it not only ensured the smooth operation of the Baotou-Lanzhou railway in the sand dune section, but also played an important role in the restoration of local eco-environment and therefore it is viewed as a successful model for the desertification control and ecological restoration along the transport line in the arid desert region of China. Long-term monitoring and located research show that 4~5 years after the establishment of sand-binding vegetation, surface physical structure of sand dunes initially became stable, and inorganic soil crusts formed by atmospheric dust gradually turned into microbiotic crusts. Among the organisms comprising the crusts are cryptograms such as desert algae and mosses etc. Over 46 years after establishing sand-binding vegetation, some 24 algal species occurred in the crusts, but only 5 moss species were identified, this is fewer than the species number in the crust of naturally fixed sand dunes. Near-surface wind velocity in 46-year-old vegetation area reduced by 54.2% compared to that in the moving sand area, soil organic matter increased from 0.06% in moving sand dunes to 1.34% of 46-year-old vegetation area, main nutrients N, P, K etc, in the desert ecosystem increased, soil physiochemical properties improved, soil-forming processes occurred in dune surface layer; the variations of soil water cycle in time and space drove the evolution of vegetation and created favorable conditions for the invasion of many herbaceous species. This also produced active effects on the existence of birds, insects, soil animals and desert animals. 46 years later, some 28 birds species, 50 insect species and 23 animal species were identified in the vegetated dune field. The restoration of biodiversity led to the transformation of the relatively single primary sand-binding vegetation into desert ecosystem with complex structure, composition and function. The restoration of eco-environment in Shapotou region under man-made favorable condition provides a scientific basis for the ecological restoration.

Key words: Tengger Desert, sand-binding vegetation, biodiversity restoration