中国森林凋落量的影响因素

Controlling Factors of Litterfall in China′s Forests

通过收集国内不同森林的凋落量、林分特征及年平均气温、多年平均降水量、经纬度、海拔等立地条件数据,分析了中国森林凋落物的影响因素.结果表明:中国森林凋落量与海拔和纬度呈极显著负相关(r=-0.245,P=0.002;r=-0.214,P=0.002),与年平均气温呈极显著正相关(r=0.303,P=0.000),与郁闭度呈极显著正相关(r=0.350,P=0.001),与经度、多年平均降水量、林分密度、平均树高、平均胸径等无显著相关性;森林类型对凋落量有显著影响(P=0.000),表现为热带林>常绿阔叶林>温带针阔混交林>暖温带落叶阔叶林>暖性针叶林>寒温带针叶林;树种组成对凋落量有显著影响(P=0.000),表现为:阔叶树>针阔混交>针叶树.

The data of the forest litterfall, stand characteristics, annual mean air temperature, annual mean precipitation, latitude, longitude and altitude in different forest sites in China were collected and analyzed for identifying controlling factors of litterfall in China＇s forests. Litterfall in China＇s forests were highly significantly correlated with altitude （ r = - 0. 245, P = 0. 002）, latitude （r = - 0. 214, P = 0. 002）, annual mean air temperature （ r = 0. 303, P = 0. 000 ） and canopy density （ r = 0. 350, P = 0. 001 ）, but were insignificant correlated with longitude, annual mean precipitation and other stand characteristics. Forest types had a significant impact on litterfall （P = 0. 000）, which was in the order of tropical forests 〉 evergreen broad-leaved forest 〉 temperate mixed forest 〉 temperate deciduous broad- leaved forest 〉 warm coniferous forest 〉 boreal forest. Species composition was also a very significant impact factor on litterfall （ P = 0. 000） which was in the order of conifers 〈 mixed conifers and broad- leaved 〈 hardwood.