云南热区几种人工幼林的土壤养分状况研究

The Study on Soil Nutrients State of Several Man-made Sapling Forests in Yunnan Tropical Area

１９９３～１９９５年，在云南省普文热带树木园内，选择４种人工纯林，５种混交林，３种天然林（对照）进行土壤养分测定，包括有机质、全氮、有效氮、有效磷、有效钾等的含量。结果０～６０ｃｍ土层的人工林土壤养分含量多呈下降趋势，除有效磷外。

From 1993 to 1995,6 kinds of pure plantations, 5 kinds of mixture forests and 3 kinds of natural forests (control) in Puwen Tropical Arboretum of Yunnan Province have been chosen to determine soil nutrients, including the contents of organic matter, complete nitrogen, available nitrogen, available phosphorus and available potassium etc. The results showed that the contents of plantation soil nutrients, Which from 0～60cm showed decline trend, and the difference fo soil nutrients, contents among every stand type is obvious except available Phosphorus.