Beech stands are considered part of the ancient forest ecosystems in the northern hemisphere.In mixed stands in beach forest ecosystems,the type of associated tree species can signifi cantly aff ect soil functions,but...Beech stands are considered part of the ancient forest ecosystems in the northern hemisphere.In mixed stands in beach forest ecosystems,the type of associated tree species can signifi cantly aff ect soil functions,but their infl uence on microbial activity,nutrient cycling and belowground properties is unknown.Here,we considered forest patches in northern Iran that are dominated by diff erent tree species:Fagus orientalis Lipsky,Quercus castaneifolia C.A.Mey.,Pterocarya fraxinifolia(Lam.),Tilia begonifolia Stev.,Zelkova carpinifolia Dippe,Acer cappadocicum Gled,Acer velutinum Boiss.,Fraxinus excelsior L.,Carpinus betulus L.,and Alnus subcordata C.A.Mey.For each forest patch–tree species,litter and soil samples(25×25×10 cm,100 of each)were analyzed for determine soil and litter properties and their relationship with tree species.The litter decomposition rate during a 1-year experiment was also determined.A PCA showed a clear diff erence between selected litter and soil characteristics among tree species.F.orientalis,Q.castaneifolia,P.fraxinifolia,T.begonifolia,Z.carpinifolia,A.cappadocicum,and A.velutinum enhanced soil microbial biomass of carbon,whereas patches with F.excelsior,C.betulus and A.subcordata had faster litter decomposition and enhanced biotic activities and C and N dynamics.Thus,soil function indicators were species-specifi c in the mixed beech forest.A.subcordata(a N-fi xing species),C.betulus and F.excelsior were main drivers of microbial activities related to nutrient cycling in the old-growth beech forest.展开更多
基金Tarbiat Modares University for the financial support of the study reported in this paper
文摘Beech stands are considered part of the ancient forest ecosystems in the northern hemisphere.In mixed stands in beach forest ecosystems,the type of associated tree species can signifi cantly aff ect soil functions,but their infl uence on microbial activity,nutrient cycling and belowground properties is unknown.Here,we considered forest patches in northern Iran that are dominated by diff erent tree species:Fagus orientalis Lipsky,Quercus castaneifolia C.A.Mey.,Pterocarya fraxinifolia(Lam.),Tilia begonifolia Stev.,Zelkova carpinifolia Dippe,Acer cappadocicum Gled,Acer velutinum Boiss.,Fraxinus excelsior L.,Carpinus betulus L.,and Alnus subcordata C.A.Mey.For each forest patch–tree species,litter and soil samples(25×25×10 cm,100 of each)were analyzed for determine soil and litter properties and their relationship with tree species.The litter decomposition rate during a 1-year experiment was also determined.A PCA showed a clear diff erence between selected litter and soil characteristics among tree species.F.orientalis,Q.castaneifolia,P.fraxinifolia,T.begonifolia,Z.carpinifolia,A.cappadocicum,and A.velutinum enhanced soil microbial biomass of carbon,whereas patches with F.excelsior,C.betulus and A.subcordata had faster litter decomposition and enhanced biotic activities and C and N dynamics.Thus,soil function indicators were species-specifi c in the mixed beech forest.A.subcordata(a N-fi xing species),C.betulus and F.excelsior were main drivers of microbial activities related to nutrient cycling in the old-growth beech forest.
