Composition,Dynamics And Its Influencing Factors Of Evergreen Broad-leaved Forest On Jinyun Mountain

Litterfall is an important component of forest ecosystem,which reflects the primary productivity of forest ecosystem.It connections plant communities and soil,and plays an important role in the process of nutrient circulation and energy flow of forest ecosystem.Natural forest is the mainstay of forest resources in China,and it is an important barrier to the sustainable development of ecology and environment.At present,there are few researches focus on the distribution pattern of litterfall and its influencing factors in different scales.Therefore,litter traps were used to monitor the pattern,dynamics and the driven factors of the litterfall in evergreen broad-leaved forest of Jinyun Mountain at the community scale.We also collected 373 litterfall literatures of natural forest published form 1970 to 2017.Litterfall production,seasonal dynamics and its driven factors(mean annual temperature,mean annual precipitation,altitude,latitude)was analyzed at the national scale.The main conclusions are as follows:(1)The average annual litterfall production of broad-leaved forest in Jinyun Mountain was 6.13±0.57 t/hm~2 from 2014 to 2017,mainly influenced by dominant tree species.The litterfall prodction was at a moderate level in subtropical region and national scale of natural forests.(2)The litterfall compositions of evergreen broad-leaved forest in Jinyun Mountain were leaf(70.27±7.63%),branch(12.62±1.73%),reproduction(12.46±9.12%),other(4.64±1.79%).The litter composition pattern was similar in local,regional and national scale of natural forests.(3)The seasonal dynamic pattern of the litterfall production of evergreen broad-leaved forest in Jinyun Mountain was mainly influenced by evergreen tree species and deciduous tree species,which showed near bimodal mode.The litterfall peaks appeared in spring and autumn respectively.There were similar seasonal patterns with subtropical evergreen broad-leaved forests and national natural forests.(4)There were significant positive correlations between litterfall production and climatic factors(mean annual temperature and mean annual precipitation)in national scale.The geographical factors(latitude and altitude)were indirect factors that influence litterfall production by redistribution of water and heat conditions.