| The natural biological crust and the artifical cultured biological crust can significantly enrich accumulation of nutrition element by 0-5cm in the soil layer. This effect canonly reach 0-5cm in the soil layer, and there is no significant effect of nutrition element in deeper soil layer. At the range of 0-5cm, the content of the available N, the available P, the available K, the available S and the available Mo shows: the content of nutrition element in natural crust is higher than the content in artificial crust and uncrusted soil. However the content of the available Mn is the highest in the artificial crust. The available N and the available P, the available K and the available Mn are highly positively correlated (P<0.01); the available P and the available Mn are highly positively correlated (P <0.01), the available P and the available K are correlated (P<0.05); the available K and the available Mn are highly positively correlated (P<0.01),the available K and the available S are positively related(P<0.05).Biological soil crusts have positive and negative effects on plant absorption of nutrients. Content of Nutrient N of seven plants growing on soil encrusted with mosses is higher than those growing on uncrusted soil. Content of Nutrient P of herbaceous plants growing on soils encrusted with mosses is not lower than those growing on uncrusted soil. Nutrient P content of semi-shrubs growing on soils encrusted with mosses is lower than those growing on uncrusted soil. This phenomenon may caused by different plant physiological activities, or the competition between biological crusts and plant roots. Within a plant life, N and P nutrients are highly positively correlated (P <0.01), P and K are positively correlated (P <0.05); Mg, Mn and S are related (P <0.05).The weighting method is adopted from condensation of water observation. The condensation water for different kinds of samples is observed from July to September. Based on the observation of the changes in amount of water condensation and the vertical changes of the condensation water, which took place every 3hours a day, the results are: the amount of water condensation in moss crust is higher than the amount in algae crust and uncrusted soil. Bryophytes have strong water-retention ability. During measurement period, the average condensation water of crust is about 0.68g, this figure accounts for 50% of water supplies of bryophytes living activities. The study indicates condensation water is an important water source of mosses.The survival rate of Bryum argenteum through indoor cultivation is the highest. The survival rate of Bryum argenteum in the soil extract and Knop nutrient solution is close to 90%. During this process, we found the propagation of Bryum argenteum equpied with diversity. A new plant can grow from the top of original plant and generated from protonema from original plant. Through the outdoor artifical cultivation of Bryum argenteum, Didymodon vinealis and Syntrichia caninervis we found the highest survival rate is Bryum argenteum. A small amount of Didymodon vinealis is alive. However there is no formation of crust. Syntrichia caninervis could not survive. The controlled trials show that the algae in the soil can form crust on thebasis of stability of the soil matrix. The algal crust coverage can reach up to 40% maxium and 25% minium in one year, which averaged 31.67%. In 2008, this coverage reached up to 90%. The total trail area in 2006 is 11.54 m~2. This area incresed to 13.48m~2 in 2008. Mosses crust coverage increased at the same time. In 2006 the coverage is only 6%, in 2007 incresed to 40%, in2008 was up to 100%. The thickness of artificial mosses crust is 1-2mm in 2006, it reached to an average of 3-5mm in 2008. The experiment of promoting formation of crust by artifical cultured mosses is needed to be further studied.
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