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新疆古尔班通古特沙漠是我国最大的固定和半固定沙漠,其间广泛发育的生物土壤结皮是除种子植物以外固定沙面的重要生物因子.地表生物土壤结皮移除后,经过1年的恢复,已形成沙粒相互黏结的状态.沙粒通过黏性菌体及其分泌物的黏结作用而相互连接,从而形成具有一定的抗外力干扰能力的结皮,但其抗压强度仅为13.42±1.38Pa.组成胞外多糖的各单糖组成中以葡萄糖、甘露糖和一种葡萄糖的同分异构体为主,其次为半乳糖、阿拉伯糖,其摩尔比依次为19︰14︰14︰6︰1.经过4年的恢复,藻类结皮逐渐形成,抗压强度增加至32.53±3.08Pa.藻结皮以陆生蓝藻具鞘微鞘藻(Microcoleusvaginatus)为优势种.此时,沙粒间依靠细菌分泌物所产生的黏结作用开始逐步减弱,取而代之的是丝状藻体更紧密和高强度的机械束缚作用以及藻体胞外分泌物对沙粒的黏结作用,对维持藻结皮的结构起着至关重要的作用,是藻结皮强度提高的主要贡献者.随着丝状藻类的生长,脱落的胶质鞘仍能够将更加细小的颗粒黏结在周围,起到一定的固定沙粒的作用.这为人工合成胶质鞘类似化合物用以固定沙面提供一定的参考依据.
Gurbantunggut Desert in Xinjiang is the largest fixed and semi-fixed desert in China, during which extensive development of biological soil crust is an important biological factor for the fixation of sand surface except for seed plants. After removal of the surface biological soil crust, The recovery of the year has formed the state of mutual cohesion of the sand grains, which are connected to each other by the cohesive action of the viscous bacteria and their secretions, thereby forming the crust with certain anti-interference ability, but the compressive strength Was 13.42 ± 1.38Pa. The composition of the exopolysaccharides in the composition of glucose, mannose and a glucose isomers, followed by galactose, arabinose, the molar ratio of 19:14 : 14︰6︰1.After 4 years of recovery, the algal crust gradually formed and the compressive strength increased to 32.53 ± 3.08Pa. The algal crust was dominated by Microcystis microtuberculosis (Microcoleus vaginatus) , Sand between rely on bacterial secretions produced by the bond began to gradually weaken, replaced by filamentous algal body more closely and high-intensity mechanical binding and algae extracellular secretions on the sand adhesion, the maintenance of algae The structure of the skin plays The crucial contribution is the main contributor to the increased strength of algal crusts. With the growth of filamentous algae, the exfoliated glial sheaths are able to bond the finer particles around, playing a role of anchoring the sand This provides a certain reference for the synthetic glial sheath compound to fix the sand surface.