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BackgroundThe invasion of non-native species is a major cause of the global biodiversity loss and creates enormous economic costs. What determines alien invasive species dominance over native plant species is still little known, but there is an emerging pattern that many of the world's worst invasive plants are successful invaders due to the signi cant connection between their clonal traits and invasiveness. Freshwater ecosystems are relatively more prone to decline and extinction of species caused by biological invasion than terrestrial and marine ecosystems. In view of the lack of information about whether or not aquatic alien species at different stages of invasion exhibit any signi cant relation with clonality, the speci c question addressed in this study was whether there is any relationship between clonality and invasiveness in aquatic macrophytes and how does it vary along different stages of invasion? ResultsWhile the link between clonality and species invasiveness has recently been recognized, whether and how clonality varies with different invasion-stages remains open questions. Hence, we tested the relationship between clonality and species invasiveness of Kashmir Himalayan aquatic macrophytes vis-à-vis its variability along different stages of invasion. The data on clonality, stage of invasion, and growth form was obtained through an extensive survey of literature and database like CLO-PLA (CLOnal PLAnts, version 3) and PLADIAS (Plant Diversity Analysis and Synthesis, 2014-2018) followed by evaluation of the clonal organs thorough intensive eld surveys undertaken over a period of 3 years (2014)(2015)(2016)(2017) in different aquatic habitats of the Kashmir valley. Our results showed that 84% of the studied species and almost 90% of the most invasive species (stage V sensu Colautti and MacIsaac 2004) are clonal. A strong positive correlation (r=0.94; p<0.05) between clonality and invasiveness was observed, which further substantiates this association at a broad geographical scale representing the whole region. From the scatter matrix and Pearson's correlation matrix, clonality seems to have a strong positive correlation with fragments, rhizomes, runners, turions, tubers, and buds, thereby further a rming the strong nexus of clonality with species invasions. ConclusionsOur results showed strong association of clonal architecture with not only the stages of invasion but also the distribution pattern of alien species in aquatic habitats, thereby indicating the pivotal contribution of clonality to invasiveness. Future studies directed at unraveling the reasons behind clonality need to be undertaken from the genomic perspective, in order to evolve better models for proper management of alien aquatic invasive species.

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Precise assessment of the impacts of invasive alien species (IAS) on ecosystem structure and functions is paramount for implementing appropriate management and restoration strategies. Here we investigated the impacts of Leucanthemum vulgare (ox-eye daisy), an aggressive invader in Kashmir Himalaya, on species diversity and primary productivity. We also evaluated bunch of strategies for the ecological restoration of the habitats invaded by this species. We found that uninvaded plots harbored on an average of 6.11 (±2.92) more species per 1m2 of quadrat than invaded plots. At multivariate scale, the ordination (nMDS) and ANOSIM exhibited significant differences between invaded and uninvaded plots with R = 0.7889 and p < 0.001. The decrease in diversity indices in invaded as compared to uninvaded plots was associated with more productive plant communities due to Leucanthemum invasion. Higher altitude Gulmarg site was more affected by Leucanthemum invasion than lower altitude Drung site. We tested different approaches for restoration and management of invaded habitats that include herbicide treatment at seedling stage, herbicide treatment before and after flowering stage, mowing and herbicide treatment together, joint mowing, digging and herbicide treatment and Leucanthemum uprooting. Among these treatments, uprooting and combined digging, mowing and herbicide treatment proved to be most effective in controlling Leucanthemum invasion. The implications of these results for effective management of ecologically sensitive and socio-culturally important landscapes are discussed.