珠江三角洲陶瓷工业污染区植被受害证据与启示

以长期暴露在大气污染胁迫下的村边林为对象,进行植物群落结构调查、植物受害分析,探讨了陶瓷工业污染排放对植被的影响。调查样地位于广东南海区五星村边坡地的半自然次生林内,乔木层和灌木、草本幼苗层的调查分别在10个10m×10m和4个5m×5m的样方内进行。该森林群落以隆缘桉和尾叶桉数量占优势,其次是乡土树种鸭脚木、泥竹,重要值依次为26.75、17.08、16.27和11.50。隆缘桉和马尾松冠层枝叶完全枯死、脱落,受害程度达100%;其次是泥竹和南岭黄檀受害程度分别为85.1%和68.3%。尾叶桉、朴树、越南山龙眼、阴香、黄荆受害程度中等,在45%—57.5%之间;其它伴生本土种类如鸭脚木、珊瑚树、酒饼叶、等的重要值较低且表现出受害程度较严重。和上层乔木比较,林下植被受污染的伤害大大降低。桉树类树种因其速生、快速郁闭等特点被认为是华南荒山、退化丘陵地区植被恢复的重要种类,但在重度污染地区已面临严重威胁,而某些乡土树种在污染地区则显示出较强的抵御大气污染的能力。本文结果为污染地区森林资源管理,退化生态系统植被恢复之树种选择以及进一步开展乡土树种抵御大气污染胁迫的过程机制与功能特征的研究提供科学基础。

Evidences and implications of vegetation damage from ceramic industrial emission on a rural site in the Pearl River Delta of China

Community structure characteristics and vegetation damage degree were investigated and analyzed in a forest around village, which had been long term exposed to ambient atmospheric pollution stress, to study the influence of airborne pollutant emissions from the concentrated ceramic industries on vegetation. Field survey was carried out in a semi-natural secondary forest on hilly land, Nanhai District of Guangdong Province, for the tree layer in ten quadrates with the total area of 10×(10 m×10 m), and for shrub and herb layers in eight subquadrates with the total area of 4×(5 m×5 m). Results showed that exotic Eucalyptus exserta and Eucalyptus urophylla were dominated over the community, followed by native tree species, Schefflera octophylla and Bambusa gibba, with the importance value (Iv) of 26.75, 17.08, 16.27 and 11.50, respectively. Among all tree species, Eucalyptus exserta and Pinus massoniana were most severely damaged with nearly 100% damaged rate. Bambusa gibba and Dalbergia balansae were injured with damaged rate of 85.1%–68.3%, however, Eucalyptus urophylla, Celtis sinensis, Helicia cochinchinensis, Cinnamomum burmanni and Vitex negundo revealed moderate injuries (45%–57.5%). Most of other indigenous species including Schefflera octophylla, Viburnum odoratissimum, Desmos chinensis, etc. showed less injured symptoms under the pollution stress. Compared with species in tree layer, damages of undergrowths were largely less. These results suggested that attention and concern should be paid on those introduced Eucalyptus species which had ever been widely used for forest restoration in degraded hilly lands of south China since 1970–1980s, due to their fast growing aspect. The results also demonstrated the potentials and perspectives by developing native species as target plants for restoration of degraded area at similar polluted location, which may provide scientific base for scientists to study and understand the functional aspects of native species and process-based interactions with pollution stress. Biography: WEN Da-Zhi (1966–), male, Ph.D., in Institute of Ecology, South China Botanical Garden, the Chinese Academy of Sciences, Guangzhou 510650, P.R. China.