Reserves and Water Capacity Characteristics of Different Stand Types in Danjiangkou Reservoir Area of Hubei Province

The litter reserve and the water holding capacity and the water absorption rate of Pinus massoniana forest,Cupressus funebris forest,the mixed forest of pine and cypress,the mixed broadleaf-conifer forest and Quercus variabilis forest were studied.The results showed that the litter reserves of different stand type had certain difference,which the litter reserves of the mixed forest of pine and cypress was the largest(29.26 t/hm2),followed by Pinus massoniana forest(24.49 t/hm2),the mixed broadleaf-conifer forest(21.93 t/hm2) and Quercus variabilis forest(16.56 t/hm2),Cupressus funebris forest litter reserve minimum(9.47 t/hm2).The dynamic changes in water holding capacity and water absorption rate and immersion time of forest litter in different lays were basically similar.With the increase of immersion time,litter water absorption rate had difference.During the process,litter water absorption's fastest growing period occurred in 0～1 h,in 1～2 h,the litter water absorption gradually slowed down,and the litter water absorption was basic saturated between 2～10 h.By fitting a regression equation,the relation formula of the water holding capacity and immersion time was Q=aln t+b,the relation formula of the water holding capacity and immersion time was V=ktn.At the same time,the maximum water holding capacity of forest litters was decomposed litter half-decomposed litter undecomposed litter.And the water absorption rate was coniferous forest half-decomposed litter decomposed litter undecomposed litter,but broadleaf forest was decomposed litter half-decomposed litter undecomposed litter.