Corrosion driving effects of three epilithic mosses in the Pudding karst area, Guizhou Province

ZHANG Kaiyan; LI Tongjian; ZHANG Xianqiang; SUN Min

doi:10.11932/karst20170403

Abstract：Bryophytes play an important role in forest ecosystems,which are irreplaceable to soil and water conservation and the improvement of the ecological environment.Due to the ecological environment deterioration of rocky desertification in Guizhou province,serious soil erosion problem have been caused,which seriously affect the production and living of the masses.So,it is necessary to strengthen the restoration and management of the ecological environment in the region.This work took three epilithic mosses,the H.microphyllum,B.argenteurn,E.leptothollum,as research materials.Using the device of simulated soil column experiment,we collected leachate and measured the carbonic anhydrase (CA) activity,electrical conductivity,pH,the content of calcium and magnesium elements and estimated the effect to limestone specimens.The results show that there are some differences about carbonic anhydrase activity of these epilithic mosses.The E.leptothollum is highest which reaches to 272.99 U · g-1.FW,whereas the minimum is 38.31 U · g-1.FW in H.m icrophyllum.All leachate was detected the existence of CA activity,and the leachate of B.argenteum 6d enzyme solution has the highest activity.In all,the CA activity in the 3 kinds of plants shows a tendency to decrease slightly fisrt,then increases,and finally tends to be stable.Their pH values exhibit a rising trend while electrical conductivity has downturn.The concentrations of Ca2+ and Mg2+ gradually drop with the extension of leaching time,and then tend to dynamic equilibrium after a certain time,which shows that the lithophyte has a significant enzymatic driving effect on limestone and there is a positive correlation between the dissolution rate and CA activity.This work is of great academic significance to further understanding the dynamics of CA activity produced by the metabolism of stone bryophytes in karst areas and their erosion to limestone.