Research On The Hydrological Effects Of Main Forest Types In Zhushatu Small Watershed Of Three Gorges Reservoir Area

Studied on the interception and water holding function of six main forest types from four ecological layers in Zhushatu small watershed of Three Gorges Reservoir Area, then the comprehensive estimating has been made on the hydrological effect of the six forest types. The results are as follows:The relationship between the precipitation and the stemflow is a linear regression. The stemflow of six forest types is Broadleaf forest, Conifer and broadleaf forest, Cupressus funebris forest, Mixed conifer forest, Pinus massoniana forest and Shrubbery and grass land in order. And there are obvious difference of stemflow among different species, the main factors that affect the stemflow are crown structure, diameter breast-high and crown width.The relationship between the precipitation and the throughfall is also a linear regression. The throughfall of six forest types is Shrubbery and grass land, Pinus massoniana forest, Cupressus funebris forest, Conifer and broadleaf forest, Broadleaf forest and Mixed conifer forest in order.The relationship between precipitation and the canopy interception is a power regression. The canopy interception will increase with the precipitation during at the beginning of rain, but it will keep stable later. The canopy interception quantity of six forest types is Mixed conifer forest, Pinus massoniana forest, Cupressus funebris forest, Conifer and broadleaf forest, Broadleaf forest and Shrubbery and grass land in order.There is much difference among the different species of the shrub and herbage. Among the species we measured, the maximum water holding specie is Abelia chinensis, and the minimum is Cudrania tricuspidata, and the water holding capacity of Abelia chinensis is three times as Cudrania tricuspidata. The shrub and herbage amount of six forest types is Shrubbery and grass land, Pinus massoniana forest, Mixed conifer forest, Conifer and broadleaf forest, Broadleaf forest and Cupressus funebris forest in order. And the water holding amount of shrub and herbage have positive relative with their amounts. The litter form amount of six forest types is Cupressus funebris forest, Conifer and broadleaf forest, Broadleaf forest, Mixed conifer forest, Shrubbery and grass land and Pinus massoniana forest in order. The half-decomposed litter form every forest type is more than that of the decomposed litter form, and the main composition of litter form is leaf, then is the branch, apart from some fruitages, barks, bud and squamule and so on. The water holding capacity of the litter form is Broadleaf forest, Cupressus funebris forest, Conifer and broadleaf forest, Mixed conifer forest, Shrubbery and grass land and Pinus...