物理措施控制互花米草的长期效果研究

Study on long-term effects of physical control measures on Spartina alterniflora

以上海崇明东滩湿地入侵植物互花米草为研究对象,进行翻耕、碎根、刈割和生物替代控制实验。在控制措施实施后第3 a的2007年生长季,继续监测不同控制措施的长期效果。研究结果显示,(1)2007年生长季初期,不同深度翻耕处理之间以及与对照已无显著性差异,翻耕处理不能长期抑制互花米草;(2)经过3个生长季,碎根处理也与对照无显著性差异;(3)不同月份刈割的处理效果之间差异显著,经过3个生长季后,8月份扬花期刈割对互花米草生长抑制的效果最好,为最佳控制时间;(4)生物替代试验中,在移栽后第3个生长季,深度翻耕处理样方中已无存活芦苇,其它样方中的芦苇存活率、植株密度、结穗率也比前两个生长季显著下降。研究结果表明,互花米草是一种适应性很强的外来物种,利用单一的物理控制措施不能长期有效地根除互花米草,必须采取综合控制措施进行治理。

A field experiment of species Spartina alterniflora physically controlled, including digging tillage, breaking rhizome, cutting, and biological substitute on invasive was conducted in Chongming Dongtan. On the basis of the research during 2005 and 2006, the growth parameters of density, coverage and aboveground biomass were noted continuously for the third growing season to search effective measures for the controlling this invasive plant. The results showed that （ 1 ） The diggging tillage treatment, there were no significant differences among the different depth treatments, and digging treatments only took effect during the first growing season, which couldnt last for a long time. （：2） There were no significant differences among the treatments and the control after three growing seasons, which showed that the interference of breaking rhizome manually wasnt enough for controlling the growth of S. alterniflora. （3） The cutting treatment at AUG remained the optimal time for controlling,while the inhibition of growth could still be found in the treatments of Jul. Aug. and Sep. at the end of third growing season. （4） The density, ear setting percentage and survival rate of the transplanted Phragmites australis decreased significantly at the end of third growing season. The survival P. australis cant be found in the plots which were dug tillage by 20 cm and 60 cm, and P. australis transplanted on the plots of breaking rhizome grew better than that on those of digging treatments. S. alterniflora is an invasive plant with a strong capacity of inter-specific competition and to withstand physical disturbances. A realistic strategy for controlling and managing the invasion of S. alterniflora in the nature reserve needs to be adopted by integrating the control measures,instead of any single control measure.