The Temporal And Spatial Distribution Characteristics Of Litter Production In An Evergreen Broad-leaved Forest In Tiantong, Zhejiang Province, Eastern China

Litterfall is one of the important components of the forest ecosystem, it plays an major role in maintaining soil fertility and nutrient balancing, conserving water and soil for forest ecosystem. Moreover, litterfall can improve the soil physical and chemical properties, influence vegetation regeneration. Evergreen broad-leaved forest widely distributes in China, and is one of the most representative forest vegetation types in the subtropical region in China. Therefore, study on dynamic features of subtropical evergreen broad-leaved forest litter has important significance. To study litterfall production, composition, temporal dynamics, spatial pattern of leaf litter, and the relationship between leaf litter and terrain, soil and community factors of20hm2dynamic plot of evergreen broad-leaved forest in Tiantong, Zhejiang, we set up187litterfall traps, and collected litterfall semimonthly form October2011to October2012. The main conclusions are as follows:1) Total annual litter production in Tiantong20hm2plot was648.25g-m-2, leaves dominated litter, accounted for70.13%of mass. Evergreen leaf litter and deciduous leaf litter accounted for50.76%and40.07%of leaf mass, the annual leaf litter production of Choerospondias axillaris contributed about18.24%of total leaf mass. The temporal dynamics litterfall and leaves followed a trimodal distribution (with peaks in April, August and November).2) The annual leaf litter of nineteen dominant tree species contributed about72.81%of total leaves mass. And it had a clear leaf litter dynamics, and these trees could be classified into three type as follows:the deciduous trees had a peak in autumn and winter, the evergreen trees had a peak in the spring or summer, and the evergreen trees had two peak in spring, autumn and winter.3) Typhoon "HAIKUI" had a certain influence in literfall production of Tiantong20hm2plot, it can cause lots of leaf litter and had different influence in leaf litter of different species. The deciduous trees had a little peak when typhoon attacked, Diospyros glaucifolia is most obvious; to the evergreen trees, Cyclobalanopsis sessilifolia and Distylium myricoides had strongest ability to against typhoon disturbance, Lithocarpus harlandii and Schima superb were weakest.4) Leaf litter in low habitat was more than high habitat, evergreen leaf litter and deciduous leaf litter had different spatial pattern. There were more deciduous leaf litter in valley habitat and more evergreen leaf litter in ridge habitat. Terrain factors had different influence on evergreen leaf litter and deciduous leaf litter. Evergreen leaf litter had positive correlation with slope, convexity, a negative correlation with elevation; The opposite results was find between the Terrain factors and deciduous leaf litter. The total leaf litter had a negative correlation with elevation.5) Soil factors had different influence on evergreen leaf litter and deciduous leaf litter. Evergreen leaf litter had positive correlation with total carbon, negative correlation with total phosphorus and soil pH. Deciduous leaf litter had positive correlation with total phosphorus, a negative correlation with total carbon. The total leaf litter had a negative correlation with total carbon and soil pH.6) Evergreen leaf litter and deciduous leaf litter had a positive correlation with basal area. But the correlation between total leaf litter and basal area, due to differences in species composition. Leaf litter production per units basal area was different in species. Among them, deciduous trees such as Choerospondias axillaris、 Acer pubinerve and Sassafras tzumu were higher, evergreen trees such as Machilus thunbergii、Cleyera japonica and Distylium myricoides were lower.