刈割与水位调节集成技术控制互花米草(Spartina alterniflora)

A demonstration study using the integrated technique of cutting plus waterlogging for the control of Spartina alterniflora

治理和控制外来物种互花米草(Spartina alterniflora)对维护崇明东滩自然保护区生物多样性具有重要的意义和必要性。研究在上海崇明东滩鸟类国家级自然保护区建立的受损滩涂湿地生态修复示范样地中开展"刈割与水位调节集成技术"治理互花米草的物理控制实验,以期寻求有效治理互花米草的控制技术。示范研究结果表明,单一的水位调节方法虽然可以降低互花米草群落的密度和叶面积指数(LAI),但至水淹处理100d后,处理样区内互花米草的生长和生物量已与对照区无显著差异。单一的水位调节方法不能达到有效快速控制互花米草的效果。通过在互花米草生长关键期(7月的扬花期)刈割+水位调节集成技术处理后,互花米草地上部分无再新生现象,至当年10月份(生长季末期),样区内互花米草的地上部分和地下部分已完全死亡并开始腐烂,达到了有效控制互花米草的效果。因此,应用刈割+水位调节集成技术治理互花米草,必须选择关键季节刈割互花米草地上部分,同时配合一定水位的持续淹水(约3个月),才能有效发挥其迅速有效治理互花米草的效果。扬花期刈割+水位调节集成技术可为沿海地区大范围防治互花米草扩散提供有效途径。

The control and eradication of the exotic and invasive plant Spartina. alterniflora at the Chongming Dongtan Nature Reserve, Shanghai is an important and necessary measure for biodiversity conservation management. A demonstration project was established at the Nature Reserve in 2007, and an integrated treatment technique of cutting plus waterlogging was conducted to investigate effective measures for controlling this invasive plant. The results showed that although treatment of waterlogging alone could significantly reduce the density and leaf area index （LAI） of S. alterniflora at the the early stage of growth, there were no significant differences in the biomass between the waterlogging treatment after 100 days, and the control. Thus, waterlogging treatment alone could not effectively and quickly control or eradicate S. alterniflora. It was observed, however, that cutting aboveground part of S. alterniflora at the key stage of growth （ i. e. the blooming period in July ） combined with waterlogging could effectively control and eradicate this plant. There was no regrowth of the emergent part of S. alterniflora after the cutting, and both the aboveground and belowground parts of S. alterniflora were killed, and the plants began to decompose at the end of the growing season （in October）. Therefore, an integrated technique of cutting at the key stage of its growth combined with waterlogging for about 3 months has been shown to be a realistic and effective technique for controlling and managing the invasion of S. alterniflora in the Nature Reserve. The results of the demonstration project could provide a useful and effective approach to controlling and managing the large scale invasion of S. alterniflora in the estuarine and coastal areas of eastern China.