The Study On Litterfall Dynamics In Maolan Karst Forest

The litterfall of forest ecosystems are important components and are an important forest surface coverage. Litterfall can be a buffer precipitation potential energy,and the absorption of surface water,so that surface runoff into the slow flow between layers and layer flow downstream,which play an important role in improving structure of soil, increase soil infiltration and soil fertility,reduce surface runoff,and reduce soil erosion.This article was written from July 2007 to December 2008 in Maolan karst broad-leaved evergreen and deciduous broadleaved forest the production of each component of litterfall dynamics and spatial dynamics of time studied.The results show that:1.Amount of litterfall production:the annual litter fall production was estimated to be 3844.58kg per hectare,lower than the tropical rain forest or monsoon forest and subtropical forest annual litter fall production.2.Monthly dynamics of litterfall production:Monthly litterfall production showed obvious seasonal dynamics of evergreen and deciduous broad-leaved Maolan karst forest. Litterfall in May(635.01kg/hm~2) peak appears,representing the amount of litterfall production was 16%,followed by October (531.50kg/hm~2) accounted for the amount of litter fall production was 13.81%;trough appears in June(211.44kg/hm~2) and July(209.86kg/hm~2),respectively,accounting for the amount of litterfall production was 5.5%.3.Monthly dynamics of each component of litterfall production: at each component,the leaf-litter production dominated the total amount of litter fall production 62%.Throughout the year, leaf-litter production showed obvious seasonal dynamics changes in May and October peaks,accounting for the amount of leaf-litter production was 28.8%;trough appears in June and July,accounting for only the amount of leaf litter production was 9.21%.Twig-litter production at January and February for peak value,falling mainly concentrated in the flower and fruit-litter in May and October.4.Monthly dynamics of the leaf-litter production of evergreen and deciduous species:the annual leaf-litter production of evergreen tree species was estimated to be 1518.72kg per hectare,the annual leaf-litter production of deciduous tree species was estimated to be 904.18 kg per hectare.The leaf-litter production of evergreen and deciduous species show obvious seasonal dynamics.leaf-litter production of evergreen species in the March,April,May month peak appears,trough appears in November.Deciduous tree species in the production of litterfall appear peak in October,a trough appears in March and April5.Monthly dynamics of different in location of slope the litter fall production:just over a hill(4080.23kg/hm2) in the production of litter fall,greater than the slope in (4033.18kg/hm2),foot(3043.17kg/hm2) in the volume of litter. Apart from January and February,just over a hill,slope,the foot of the slope change model is similar,in May and in October reach the peak.At different slope position of each component, all components of a larger dynamic changes between month.6.Monthly dynamics of litter fall production and spatial dynamics:From July 2007 to December 2008,litter fall production and temperature,relative humidity,rainfall on the monthly dynamic changes in different,temperature and relative humidity have no obvious effect on the amount of litter dynamics.However,the rainfall has an obvious effect on the month of litter fall production and the amount of leaves on the monthly dynamic,namely:the production of their litter and rainfall were negatively related to each other.