粤东五华县亚热带季风常绿阔叶林退化生态系统恢复的初步研究

PRELIMINARY STUDY ON THE RESTORATION OF SUBTROPICAL MONSOON EVERGREEN BROAD-LEAVED FOREST IN WUHUA COUNTY, GUANGDONG PROVINCE

研究了粤东五华县亚热带季风常绿阔叶林退化生态系统恢复过程不同演替阶段的植物群落种群和生境的变化，揭示退化生态系统的植被恢复过程及其效应。1.人为破坏较轻、尚保存有一定原生植被繁殖体的次生林地，通过封山育林，可较快地促进其恢复成较为稳定的森林生态系统。历时2年，在400m2样方内，常绿阔叶林乔木层树种增加了5种，幼苗数量增加了186株，并已有一些中生性种类入侵。生境亦有所改善，气温、地表温、土温以及相对湿度的变幅趋于平缓，相对湿度更处在一个相对较高且较为稳定的水平；土壤变为强酸性减弱，全氮和速效磷含量升高，植被正向演替进程相对较快。2.在生态系统退化较严重的散生马尾松灌丛草坡，因受附近阔叶林的影响，新的物种较易入侵，在100m2样方内植物种类共增加了2种56株。3.在严重水土流失的散生马尾松草坡，生态系统极度退化，仅靠植被的自然恢复极其困难，需要一个相当漫长的过程，而人为的持续干扰和破坏是植被恢复的极大障碍。

Changes of species diversity and eco-environment at different successional stages in degraded ecosystem of subtropical monsoon evergreen broad-leaved forest were studied from January 1994 to October 1995, in Wuhua county, Guangdong Province, where the sites surveyed were low hills at 160 -180 m altitude. The forest coverage here was only 2.2%. and soil erosion accounted for 61.1% of the total sites studied. Three fixed plots were set up in different communities, namely secondary forest (400 m2) that had been disturbed slightly, scrub-herbosa (100 m2) that had been severely disturbed, and herbosa (25 m2) with serious soil erosion. The results indicated that the restoration of the secondary forest was quite rapid under strict protection of the whole hill. The number of tree species and individuals with height less than 1.5 m increased in the plot by 5 and 186, respectively, meanwhile, the eco-environment of the community was improved. The restoration of the scrub-herbosa was also fast by taking the same measure as above, and the number of broad-leaved tree species and individuals increased by 2 and 56 in the plot, respectively. But the restoration of the herbosa was rather slow. Few broad-leaved trees could live in this type of community, and it increased only by 1 species of broad-leaved trees in the plot within two years.