Assessing harmony in distribution patterns of plant invasions: a case study of two invasive alien species in India
Climate change enhances invasive species distribution by altering species composition in native ecosystems. Here we assessed harmony in plant invasions of two perennial exotic species of similar origin and naturalised in India, i.e., Chromolaena odorata and Tridax procumbens. Predictions made for the current condition was subsequently projected for the years 2050 and 2100 for both moderate and extreme climate change scenarios. Maximum Entropy (Maxent) was applied to assess their habitat suitability, risk area identification and shifts in range sizes. The distribution of C. odorata could mostly depend on temperature and moisture availability; and invade the biodiversity-rich regions of India viz., the Eastern Ghats, the Western Ghats, the Eastern Himalaya and the north-eastern regions. The prevalence of T. procumbens in central regions of India could demonstrate its greater dependencies on precipitation seasonality and radiation than that on temperature. These discrepancies in climatic dependencies allowed both for a harmonious distribution, i.e., inhabiting in regions not utilised by other. Both are likely to reduce their potential distribution areas in the future climate, where moisture availability is a key factor for their range expansion. The capacity to tolerate a wide range of temperature and solar radiation allowed T. procumbens to manage climate change impacts more efficiently, compared with C. odorata. The present study reveals harmony in their distributions and suggests distinct conservation protocols for each of them to control their invasion risks.