土壤填埋对四种树木的成活率和生长的影响

因房屋建筑、隧道、地铁等施工而产生的大量土方用于填埋林地而对树木产生的影响研究尚未见报道。本文对建筑土方填埋后的4种树木的成活率和生长情况进行了调查分析，初步了解了不同树种的响应差异，其中，杂交马褂木（Liriodendron chinense×L. tulipifera）最敏感，当填埋土壤的高度达数十厘米时就会出现死亡现象；填埋高度达2 m以上时，杂交马褂木的死亡率就会达到80%以上。但是，池杉（Taxodium ascendens）和东方杉（Taxodium mucronatum × Cryptomeria fortunei）即使在3 m以上的填埋高度下，1年后也没有出现死亡现象。喜树（Camptotheca acuminata）的表现介于中等状态。树木的胸径生长趋势与成活率相似。与未填埋土方的林地相比，填埋土方后的林地土壤呼吸速率会明显下降。综上所述，可以认为池杉和东方杉对土壤填埋处理的抵抗力较强，其次是喜树，而杂交马褂木的抵抗力较弱。

Effects of soil dumping on survival rates and growth of four species of trees

Constructions of housing, tunnel and subway in cities produce the large amount of soil. The soil is often dumped into the forest, but the effects of the soil dumping to the trees were unclear. In this paper, survival rates and growth of four species of trees were investigated when the trees were dumped by construction soil. The main results showed that Liriodendron chinense× L. tulipifera was the most sensitive to the soil dumping. When the depth of dumping soil was about tens of centimeter, Liriodendron chinense× L. tulipifera had phenomenon of death. When the depth of dumping soil was above to two meters, the death rates were more than 80%. However, Taxodium ascendens and Taxodium mucronatum× Cryptomeria fortunei had no phenomenon of death although the depth of dumping soil was above to three meters. Meanwhile Camptotheca acuminata had medium status. Growth tendency of diameter at breast height of four trees species was similar to survival rates. Respiratory rates of soil were obviously decreased when the forest were dumped by construction soil. It was suggested that the resistances of Taxodium ascendens and Taxodium mucronatum× Cryptomeria fortunei to the soil dumping were strong, Camptotheca acuminata was medium, Liriodendron chinense× L. tulipifera was weak.