新乡24种园林绿化树木叶片含硫量比较

Comparisons of sulfur contents in leaves of 24 landscape afforestation trees in Xinxiang City

为了探讨新乡市园林绿化树木叶片硫累积量的差异性,于2011年春秋季节选择5个功能区24种绿化树木,对其叶片含硫量进行比较并运用K-均值聚类法进行分类。结果表明:除女贞之外,其它绿化树木叶片含硫量随春秋季节的变异呈现递增趋势,绝大多数绿化树木春秋季节差异显著;与清洁区相比较而言,污染区域所供试的几乎所有的绿化树木叶片含硫量都较高。根据5个功能区绿化树木叶片含硫量均值进行分类,杨树叶片含硫量相对较高,归为第一类;大叶黄杨、银白杨、榆树、垂柳、白蜡、五角枫、枇杷、小叶黄杨和臭椿叶片含硫量居中,归为第二类;第三类包括无花果、构树、悬铃木、椤木石楠、国槐、小叶女贞、合欢、紫叶李、栾树、女贞、紫荆、红叶石楠、凤尾兰和海桐,叶片含硫量相对较低。不同类型的树木叶片含硫量差异性表现为落叶阔叶乔木>阔叶灌木>常绿阔叶乔木。

In order to explore the differences of sulfur accumulation amount in leaves of landscape green trees in Xinxiang city, 24 ornamental and afforestation trees were chosen among five function areas in Spring and Autumn in 2011, and the leaves sulfur contents of different trees were compared and classified by K-means Cluster. The results indicate that the sulfur contents of tree leaves increased according to seasonal variation of Spring and Autunm, the season variation for some trees was significant, except for Ligustrum lucidum Ait. In comparison with cleaning areas, the sulfur contents of all but afforestation trees were relative higher in polluted areas. The tree species were classified on the basis of mean leaves sulfur contents, Populus canadensis was classified to the first category and its sulfur content was relative higher. The second category includes Buxus megistophylla, Populus alba, Ulmus pumila, Salix babylonica, Fraxinus chinensis, Acer elegantulum Fanget, Eriobotrya japonica, Buxus sinica and Ailanthus altissima, theirs sulfur contents were at medium levels. The third category included Ficus carica, Paper mulberry, Platanus hispanica, Photinia davidsoniae, Sophora japonica Lirm., Ligustrum quihoui, Albizia julibrissin Durazz, Prunus cerasifera, Koelreuteria paniculata, Ligustrum lucidum Ait, Cercis chinensis, Photinia serrulata, Yucca gloriosa, Pittosporum tobira and theirs sulfur contents were at relative lower levels. The foliage sulfur contents of different tree types were different, the order ranked as following： deciduous broad-leaved arbor 〉 broad-leaved shrub 〉 evergreen broad-leaved arbor.