准噶尔盆地古尔班通古特沙漠生物结皮蓝藻研究

通过对古尔班通古特沙漠中9个样地73份生物土壤结皮蓝藻的研究，分析该沙漠生物结皮中蓝藻的区系组成、生态分布特点和蓝藻在生物结皮中的作用机制。研究表明，该沙漠中有蓝藻门植物6科25属77种，其中以丝状种类占优势；蓝藻在不同地貌部位分布略有差异，在丘间低地种类最为丰富；不同种类的蓝藻对地貌部位的选择性不同，大部分对地貌部位具有选择性；蓝藻种类和数量在结皮层较多，在结皮下层明显减少。生物结皮的显微观察揭示了丝状蓝藻和胞外多糖形成错综复杂的网状结构，起着捆绑、黏结沙粒和固定沙粒的作用。

Study on Cyanobacteria of Biological Soil Crusts in Guerbantunggut Desert,Zhungar Basin,Sinkiang

Cyanobacteria collected from biological soil crusts of Guerbantunggut Desert of Sinkiang is cultured,observed and identified. The flora composition,ecological distribution and the action mechanism of cyanobacteria in biological crusts in the desert are preliminarily analyzed in this paper. The results show that there are 77 species belonging to 25 genera and 6 families, in which filamentous cyanobacteria are dominant in the desert. There are some differences in the distribution of varied physiographical places. Taxa in inner dune are more abundant than those in windward,top and leeward of sand dune. Most species have choice to the varied physiographical places and some species have no choice. Taxa and numbers of cyanobacteria in inner crust are abundant and decrease obviously under the crust. Microscopic examination of micro- biotic crusts in this study revealed an intricate network of filamentous cyanobacteria and exopolysaccharides, which binds sand grit and oonglutinates fine particles, and is propitious to keep sand particles stabilization and reduce water and wind erosion.