关 键 字(英文)：Air pollution Woody species Gross caloric value Ash-free caloric value C/N ratio
摘 要(英文)：Seedlings of nine tree species grown in pots were exposed to contamination environment of sulphur and fluoride at Nanzhuang town, a ceramic industry area in Fushan city, Guangdong, and another part of the same plants were potted at South China Botanical Garden as control. The dry matter of seedling leaves was used to measure the gross caloric value by oxygen-bomb calorimeter. The ash content, ash-free caloric value and the ratio of N and C were also determined. The results showed that the caloric values in Ilex rotunda, Machilus chinensis and Lysidice rhodostegia were relatively high (above 19.00 kJ g-1), and the values in Koelreuteria bipinnata, Ficus annulata, Michelia chapensis, Ficus microcarpa and Camellia semiserrata were lower (between 18.00-19.00 kJ g-1) than the above three species, but higher than the value of Spathodea campanulata, which is lower than 18.00 kJ g-1. The air pollution stress caused the increase of gross caloric values in Koelreuteria bipinnata, Machilus chinensis and Ilex rotunda,but decrease of those in Lysidice rhodostegia, Michelia chinensis, Ficus microcarpa, Spathodea campanulat and Camellia semiserrata. However, the caloric values of Ficus annulata had only little change between polluted and less polluted environments. The analysis of Pearson correlation coefficients showed that the ash-free caloric value in leaves of the seedlings of 9 species did not significantly correlate with the C/N ratio and the ash content for corresponding species. However, the fluctuations of leaf caloric values in the same species under different environments were related to the pollution tolerance of the species, suggesting that the caloric value in leaves can be considered as an index of species sensitivity to air pollution.
大气污染胁迫下9种植物幼苗叶片热值、C/N和灰分含量比较