中国栽培的香根草是外来入侵种并会蔓延成为杂草吗?

Is vetiver grass planted in China an invasive alien species and becoming a weed?

1988年国际香根草网络主席里查德·格雷姆肖先生引入到中国的香根草技术是一种利用香根草进行水土保持、环境保护、生境恢复、防灾减灾、污染治理的生态工程与植物修复技术。在过去20多年,该技术应用到中国南方10多个省区,取得了显著的生态效益与社会效益。然而,当年引入香根草技术时,海南、广东、福建等地早已有"野生"的香根草存在,甚至可以追溯到1936年。而最初的香根草种源究竟是中国本土生长还是从国外引入?至今未见确凿的证据或资料。目前,世界上栽种的香根草是通过分蘖等无性繁殖的,在中国未发现香根草的无序蔓延及其"排他"现象。与此相反,由于香根草的种植可改善恶劣的生境条件,使其他乡土植物得以很快定居并生长,从而导致香根草自身萎缩甚至消失。此外,香根草对除草剂非常敏感,常因除草剂的喷洒而消失。因此,把香根草当作外来入侵种并认为会成为杂草的说法是缺少科学依据的。

The Vetiver Grass Technique （VGT） was introduced into China in 1988 via Mr. Richard Grimshaw, the Chairman of International Vetiver Network. It is an excellent coo-engi- neering and phytoremediation technology that has been used for the purposes of soil and water conservation, environmental protection, habitat restoration, disaster and pollution control and so on. In the last two decades, VGT has been applied to over a dozen of provinces in southern Chi- na, and has made significant ecological and social benefits. As a matter of fact, before it was in- troduced into China, ＂wild＂ vetiver had already existed in Hainan, Guangdong, Fujian for long time, which can be traced back to 1936. However, there has not been conclusive evidence or in- formation so far whether the vetiver is native to China or imported from abroad. At present, the only reproduction method of the cultivated vetiver around the globe is through asexual means （e.g., tillering） , and vetiver sprawl and ＂repellent＂ phenomena haven＇t been found in China. In contrast, vetiver can improve harsh habitat conditions and therefore benefits the growth of other native species, which subsequently leads to the shrinking or even disappearance of vetiver due to its poor tolerance to shade. In addition, vetiver is particularly sensitive to herbicides, and there- fore, often can be completely annihilated by the spraying of herbicides. In conclusion, there is no scientific basis to conclude that vetiver is an alien invasive species and has potential to become a weed.