Department of Environment Studies, Panjab University, Chandigarh, 160014, India,
Environ Monit Assess. 2014 Jun;186(6):3379-89. doi: 10.1007/s10661-014-3624-x. Epub 2014 Jan 30.
Lantana camara, an aromatic shrub, native to tropical America, was introduced into India for ornamental hedging, but later escaped and became a serious invasive weed. This study assessed the quantitative and qualitative status of plant community richness and diversity in areas invaded by L. camara in the Siwalik Hills (Himachal Pradesh, India), and explored allelopathy as a possible mechanism of interference. We measured species diversity, richness and evenness of the vegetation in areas invaded and uninvaded by L. camara. Allelopathic effects of L. camara rhizosphere soil and litter were assessed against two native plants-Achyranthes aspera (a herb) and Albizia lebbeck (a tree). Density, biomass and indices of diversity, richness and evenness were reduced by L. camara, indicating a significant alteration in composition and structure of native communities. Seedling growth of the test species was reduced in L. camara rhizosphere- and litter-amended soil. The inhibitory effect was ameliorated by the addition of activated charcoal, indicating the presence of organic inhibitors (quantified as phenolics) in the soil. Lantana invasion greatly reduces the density and diversity of the vegetation in the invaded area, and chemical interference of its litter plays an important role in invasion.
马缨丹，一种芳香的灌木，原产于热带美洲，被引入印度作为观赏树篱，但后来逃逸并成为一种严重的入侵杂草。本研究评估了喜马偕尔邦西瓦利克山脉（印度）被马缨丹入侵地区植物群落丰富度和多样性的定量和定性状况，并探讨了化感作用作为一种可能的干扰机制。我们测量了马缨丹入侵和未入侵地区的植被物种多样性、丰富度和均匀度。评估了马缨丹根际土壤和凋落物对两种本地植物（牛膝和合欢）的化感作用。马缨丹的密度、生物量以及多样性、丰富度和均匀度指数降低，表明本地群落的组成和结构发生了显著变化。在添加马缨丹根际土壤和凋落物的土壤中，测试物种的幼苗生长受到抑制。在添加活性炭后，抑制作用得到缓解，表明土壤中存在有机抑制剂（以酚类物质定量）。马缨丹的入侵大大降低了入侵地区植被的密度和多样性，其凋落物的化学干扰在入侵中起着重要作用。
