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生物土壤结皮广泛分布于干旱和半干旱区,它的形成和发育对荒漠生态系统生态修复过程产生重要的影响。采用野外调查、测定和室内分析相结合的方法,对毛乌素沙地南缘沙丘生物土壤结皮发育特征进行研究。结果表明:不同地貌部位生物土壤结皮的厚度、各类型结皮盖度、机械组成和结皮及其下层剖面土壤容重均发生不同程度的变化。生物土壤结皮的发育对不同地貌部位具有一定的选择性,丘顶微生物结皮少量分布,迎风坡以浅灰色的藻类结皮为主,背风坡以黑褐色的藻类结皮为主,丘间地以苔藓结皮为主。不同地貌部位结皮层微生物总数存在较大差异。不同发育阶段生物土壤结皮的优势成分不同,表现出明显的阶段性特点,其形成和发育是生物过程和非生物过程的统一。
Biological soil crusts are widely distributed in arid and semi-arid regions, and their formation and development have an important impact on the ecological restoration of desert ecosystems. Using the method of field investigation, determination and laboratory analysis, the characteristics of biological soil crusts development in the dunes of the southern Mu Us Sandy Land were studied. The results showed that the thickness of biological soil crusts, the crust cover of all kinds, the mechanical composition and crusts, and the bulk density of soil below the soil profiles varied with different degrees. The development of biological soil crusts showed a certain selectivity to different topographic parts. The microbial crusts at the top of the hill were slightly distributed. The light gray algal crusts on the windward slope were dominated. The leeward slope was dominated by dark brown algal crusts. Moss crust-based. There are big differences in the total number of microorganisms in the cortex of different landforms. The dominant components of biological soil crusts at different developmental stages are different, showing obvious stage characteristics. Their formation and development are the unification of biological and non-biological processes.