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

Comparison of Caloric Value, C/N Ratio and Ash Content in the Leaves of Seedlings of Nine Species under Air Pollution Stress

摘要:

用氧弹热值仪测定了生长在硫和氟复合污染环境和相对洁净环境下的9种木本植物幼苗叶片热值。结果表明，植物叶片的基础干重热值、灰分含量因种类不同而有差异，其中热值较高的(大于19.00 kJ g^-1)植物有铁冬青(Ilex rotunda)、华润楠(Machilus chinensis)和仪花(Lysidice rhodostegia)，热值中等的(介于18.00-19.00 kJ g^-1)植物有复羽叶栾树(Koelreuteria bipinnata)、环榕(Ficus annulata)、乐昌含笑(Michelia chapensis)、小叶榕(Ficus microcarpa)和红花油茶(Camellia semiserrata)，热值低的(低于18.00 kJ g^-1)种类有火焰木(Spathodea campanulata)。大气污染导致复羽叶栾树、华润楠和铁冬青幼苗叶片基础干重热值增加，仪花、含笑、小叶榕、火焰木和红花油茶幼苗叶片基础干重热值下降，环榕基础干重热值则维持相对稳定。Pearson相关系数分析表明，9种植物幼苗叶片去灰分热值与叶片自身C／N比、叶片灰分含量的相关性均不显著，但污染胁迫下植物幼苗叶片热值相对波动程度与其对污染物的抗性有关，提示叶片热值可以作为植物幼苗对硫和氟复合污染的敏感性指标。

Abstract:

Seedlings ofnine tree species grown in pots were exposed to contamination enviroriment of sulphur and fluoride at Nanzhuang town,a ceramic industry area in Fushan city,Guangdong,and another part ofthe same plan ts were pored at South China Botanical Garden as contro1．The dry matter of seedling leaves was used to measure the gross caloric value by oxygen-bomb calorimeter．The ash content，ash-flee 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 relativelyhigh (above 19.O0 kJ g^-1 )，and the values in Koelreuteria bipinnata, Ficus annulata, Michelia chapensis，Ficus microcarpa and Camellia semiserrata were lower(between 1 8.00-1 9.00 kJ g^-1 )than the above three species，but higher than the value of athodea campanulata，which is lower than 1 8．00 kJ g^-1．The air pollution stress caused the increase of gross caloric values in Koelreuteria bipinnata,Machilus chinensis and Ilex rotunda,but decrease ofthose in Lysidice rhodostegia, Michelia chinensis，Ficus microcarpa, athodea campanulat and Camellia semiserrata． However， the caloric values ofFicus annulata had only litle change between polluted and 1ess polluted environments． The analysis of Pearson correlation coefi cients showed that the ash-flee caloric value in leaves of the seedlings of 9 species did not significantly corelate with the C／N ratio and the ash content for coresponding species．However，the fluctuations of leaf caloric values in the same species under diferent 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．