广东地区三种木本植物抗大气污染能力的比较

Comparison of the Resistance of Three Woody Plant Species to Air Pollution in Guangdong Province

摘要:

研究了工业污染区(佛山市小塘镇五星WX)和相对清洁区(广州华南植物园BG)生长的3种木本植物光叶山矾(Symplocoslancifolia)、银柴(Aporosachinensis)和窿缘桉(Eucalyptusexserta)叶片对酸碱缓冲能力的差别。工业污染区3种植物的细胞液pH均比相对清洁区的低,光叶山矾与银柴对酸和碱的缓冲能力强于窿缘桉。用外源NaHSO₃处理,植物叶片的光合放氧、Fv/Fm、Fv/Fo和ΦPSⅡ都有不同程度的下降。其中,窿缘桉下降的幅度最大,说明其抗大气污染的能力不如光叶山矾和银柴,同时也证明了用缓冲能力作为一种评价植物抗污能力的指标具有一定的科学性。

Abstract:

Response of three woody species (native Symplocos lancifolia and Aporosa chinensis, and exotic Eucalyptus exserta) to air pollution grown at two experimental sites, Wuxing with ceramic factories nearby at Foshan city (WX) and control site at South China Botanical Garden (BG), was examined physiologically. Buffering capacity of S. lancifolia and A. chinensis was higher than that of E. exserta. pH in cell sap of leaves of three species was lower in WX than that in BG. After the leaves were treated with 10 mmol L^-1 NaHSO₃ under 20.5μmol m^-2s^-1 light intensity for 10 h, the photosynthetic oxygen evolution, Fv/Fm, Fv/Fo and ΦPSⅡ in all the three species decreased to some extent, most significant decrease in three parameters was found in E. exserta. The results demonstrated that there was less resistance to air pollution in E. exserta than in the other two, and it was consistent with different buffering capacity of cell sap in three species. It is suggested that the buffering capacity of cell sap in plant leaves can be a useful index in evaluating the resistance of plants to SO₂ pollution.