Ecological and environmental explanation of microbiotic crusts on sand dune scales in the Gurbantonggut Desert, Xinjiang
Results obtained from the field investigation and the analysis in laboratory show that many species of microbiotic crusts of lichens, mosses and algae develop extensively in the Gurbantonggut Desert, Xinjiang. The formation, species and distribution are closely related to the environmental conditions at the different positions of sand dunes. The animalcule crusts develop mainly on the mobile or semi-mobile sand surface of dune tops, the alga crusts develop mainly at the upper to middle parts of dune slopes, the lichen crusts develop at middle and lower parts of dune slopes, and the moss crusts are mainly distributed at the lower part of dune slopes and the interdune lowlands. The species, thickness and developing degree of microbiotic crusts increase from the upper part to the middle and lower parts of dune slopes and the interdune lowlands, and an obvious contrast between the microbiotic crusts and the different species of plant communities forms. The development and differentiation of microbiotic crusts at the different positions of dunes are the ecological appearance and the natural selection of synthetic adaptability of the different microbiotic crust species to the local environmental conditions, and are closely related to the ecological conditions, such as the physiochemical properties of soils and stability of topsoil texture.
作 者： CHEN Yaning LI Weihong ZHOU Zhibing LIU Jiazhen 作者单位： Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China 刊 名： 自然科学进展（英文版） SCI 英文刊名： PROGRESS IN NATURAL SCIENCE 年，卷(期)： 2005 15(12) 分类号： P5 关键词： microbiotic crust sand dune scales environmental explanation the Gurbantonggut Desert