8种灌木滞尘能力及叶表面结构研究

Dust-retaining capability and micro morphology structure of leaves of eight shrubs

为研究不同植物的滞尘规律,以青岛市城阳区道路绿地中的8种灌木(大叶黄杨、火棘、红叶石楠、金叶女贞、连翘、珍珠梅、红瑞木、小蜡)为研究对象,测定各植物的滞尘量,探究植物叶表面结构与其最大滞尘量的相互关系.结果表明,8种灌木中常绿灌木的滞尘量普遍比落叶灌木高,大叶黄杨、火棘在春季雨后30 d的平均单位叶面积滞尘量较高,可达到1.4 g·m-2,连翘的滞尘量较低,仅为0.9 g·m^(-2);各灌木达到单位叶面积内最大滞尘量的时间在21 d到27 d不等,平均在第24天左右,单位叶面积最大滞尘量最高的火棘(2.02 g·m^(-2))达到最低的连翘滞尘量(1.07 g·m^(-2))的近2倍;8种灌木各季节的平均滞尘量总体上表现为秋季>春季>夏季.叶表面结构观测表明,叶表面平整但蜡质层较厚、气孔密集且开口较大的植物滞尘能力较高,同时得到8种灌木最大滞尘量与叶表面结构的拟合曲线,结果表明,滞尘量与气孔大小呈正相关关系,与沟槽比例呈负相关关系,与叶毛数量、气孔密度关系不显著.

In order to study the dust-detaining capability and its rules of different plant, eight shrubs （ Euonymus japonicas, Pyracantha fortuneana, Photinia x frasery, Ligustrum x vicaryi, Forsythia suspense, Sorbaria sorbifolia, Comus alba, Ligustrum sinense ） in road greenbelt in Chengyang district of Qingdao city were chosen to measure and compare its content of dust retention, and the interrelations between surface structure of the leaves and its largest content of dust retention were explored. The results showed that in eight shrubs, the content of dust retention of evergreen shrubs was generally higher than deciduous shrubs. The average content of dust retention per unite leaf area of Euonymus japonicus and Pyracantha fortuneana within 30 days after the rain in spring was high （up to 1.4 g· m-2）, while Forsythia suspensa was low （only 0.9 g·m-2）. The duration of shrubs getting to the largest content of dust detention per unite leaf area was 21 days to 27 days with an average of 24 days. The highest cumulative content of dust detention per unite leaf area of Pyracantha fortuneana （ 2.02 g·m-2） was nearly twice of the lowest cumulative content of Forsythia suspensa （1.07 g·m-2）. The changed trend of content per unite leaf area of eight shrubs in each season generally was autumn〉spring〉summer. Higher dust-retaining capability of plant was found in smooth but thick waxy leaves, or leaves with denser and big stomata, by observing the surface structure of the leaves. The fitting curves for the largest content of dust retention of eight shrubs to the surface structure of the leaves was plotted, which showed that the largest content of dust retention of eight shrubs had positive correlation with stomata size on the leaf surface and had negative correlation with groove proportion, but the relationships between the content of dust retention and the number of leaf hairs, stomata density were not significant.