中国南部天然常绿阔叶林的凋落物养分归还

NUTRIENTS RETURN OF LITTERFALL OF A NATURAL EVERGREEN BROAD-LEAVED FOREST IN SOUTHERN CHINA

自1989年至1992年对江西省九连山自然保护区的天然常绿阔叶林通过凋落物归还到枯枝落叶层的养分量进行了测定。凋落物的干重约为6.4t/hm^2·a～8.8t/hm^2·a,其中叶凋落物约为4.3t/hm^2·a～4.7t/hm^2·a。养分归还量氮、磷、钾、钠、钙和镁各为68kg/hm^2·a～85kg/hm^2·a,3.1kg/hm^2·a～3.8kg/hm^2·a,21kg/hm^2·a～67kg/hm^2·a,4.4kg/hm^2·a～6.8kg/hm^2·a,113kg/hm^2·a～160kg/hm^2·a 和19kg/hm^2·a～28kg/hm^2·a。氮和磷的归还量小于而钙的归还量大于热带雨林。

Amounts of nutrients returned to forest floor through litterfall were measured from 1989 to 1992 in a natural evergreen broad-leaved forest in the Jiulianshan Natural Reserve,Jiangxi Province.The dry weights of Litterfall were about 6.4t/ha·y～8.8t/ha·y with about 4.3t/ha·y～4.7t/ha·y of leaf litter.Amounts of nutrient return were 68～85 for nitrogen,3.1～3.8 for phosphorus,21～67 for potas- sium,4.4～6.8 for sodium,113～160 for calcium and 19kg/ha·y～28kg/ha·y for magnesium,respec- tively.Amounts of nitrogen and phosphorus were less and amount of calcium larger than for tropical rain forests.