Effect Of Culture Medium On The Growth Of Drought Tolerant Mosses Species

As the major type and advanced successional stage of biological soil crusts, moss crustplay a vital role in fields of ecological, economical, gardens and so on. Especially in arid andsemi-arid areas, moss crust play several important ecological roles, such as improving soilresistance to wind and water erosion and enhancing soil fertility, which created suitableconditions for the invasion and settlement of herbs, which will resulted in flux sand fixation.recently, many researches have been concentrated on artificial culture of moss crusts and onits application in soil desertification controlling. In the study, drought tolerant moss species,Bryum argenteum, Barbula tectorum, Barbula unguiculata and Funaria hygrometrica whichwidely distributed in arid and semi-arid area were taken as the propagative materials todevelop artificial moss crusts on different mediums, Iso as to determine the suitable culturemedium for artificial culture of moss crusts. Nutrition conditions (different concentrations ofhumic acid, soil extract, cow dung extract solution, molasses solution and glucose), pH, thethickness of medium were studied in growth chamber as well as under field conditions. Theresults showed that, moss crust can be cultured on soils; the coverage and density of mossesreached a high level in particular temperature, moisture, light and other conditions. Theresults are as follows:1）Effect of different nutrient on formation and development of moss crustThe formation and development of B. argenteum crusts and B. tectorum crusts could beincreased by adding30mg/l、40mg/l humic acid and soil extract, which soil-water ratio was1:8. Humic acid in favor of F. hygrometrica crusts in later stage. Below the10mg/lconcentration, molasses solution was benefit to the growth of B. argenteum crusts, the higherconcentration of30g/l inhibited.30g/l glucose inhibited the growth of B. argenteum crusts.The soil medium were contaminated by massive bacterial pathogens from cow dung extractsolution, inhibited obviously the growth of moss crusts.2）Effect of nutrient on formation and development of different moss speciesAdding soil solution and40mg/l humic acid separately into soil medium, B. argenteum,B. tectorum were taken as the propagation materials, moss crust can be cultured with asignificantly higher cover and density than F. hygrometrica. The result suggested, in the field condition, B. argenteum and B. tectorum were more suitable to be used as the propagationmaterials than F. hygrometrica when cultured moss crusts.3）Effect of pH on formation and development of moss crustB. tectorum crusts and B. unguiculata crusts didn’t show significantly different in the pHrange of7.0-8.0. Cultured for60days under laboratory conditions, the cover degree of B.tectorum crusts and B. unguiculata crusts was about90%. It did not need to adjust pH whenthe water pH was7.0-8.0.4）Effect of medium thickness on formation and development of moss crustIt took a shorter period for2cm soil to get the same moss coverage compared with1cm.About35days, the moss crust cover and density of2cm layer reached approximately77%,while1cm thickness of the medium achieved the maximum at the end of cultivation56days,which was about78%.