沙质海岸防护林入侵植物垂序商陆的防治

垂序商陆的入侵给我国沿海防护林造成了严重危害.本研究在入侵程度相对一致的刺槐林下设置样地,采用物理(刈割、切根)、化学(喷洒无公害除草剂)方法进行控制试验,并以林下紫穗槐发育良好、未进行处理的地段作为对照,探索控制垂序商陆生长的有效方法.结果表明:刈割能快速降低垂序商陆各项生长指标,但次年即恢复至对照水平.1/3切根仅减少了当年地上部分生长量,第3年又恢复至处理前水平,而2/3切根和完全切根处理一次即可有效地清除垂序商陆.精喹禾灵和百草枯仅能杀死其地上部分,次年即恢复至处理前水平,而45g·L-1草甘膦处理的垂序商陆死亡率达到100％,第3年新萌发垂序商陆生长与结实量已明显恢复.紫穗槐发育良好地段的垂序商陆各生长指标始终处于较低的平衡状态.采用紫穗槐替代法是长期控制垂序商陆的有效防治方法.

Prevention and control of invaded plant phytolacca americana in sandy coastal shelter forests

The invasion of Phytolacca americana has produced serious damage to the coastal shelter forests in China. In order to search for the effective measures for controlling the growth of P. americana, several plots in the Robinia pseudoacacia forest invaded by P. Americana to the relatively same extent were installed, and the measures of physical control (mowing and root cutting) and chemical control (spraying herbicides) were adopted to control the invasion of P. Americana, taking the site with good growth of Amorpha fruticosa in the forest and without any control measures as the comparison. The results showed that mowing could rapidly decrease the growth of P. americana in the same year, but the growth recovered in the next year. 1/3 root cutting only reduced the aboveground growth of P. americana in the same year, and the growth was recovered in the third year; while 2/3 root cutting and whole cutting could effectively cleanup the P. americana plants all the time. Spraying quizalofop-p-ethyl and paraquat only killed the aboveground part of P. americana in the same year, but this part of P. americana recovered to the normal level in the next year; while spraying 45 g x L(-1) of glyphosate could completely kill the whole P. americana plants till the third year. The growth of P. americana at the site with good growth of A. fruticosa and without any control measures maintained at a low level all the time, suggesting that planting A. fruticosa in R. pseudoacacia forest would be an effective approach to prevent and control the P. americana invasion.