Prosopis juliflora is one among the dominant invasive plant species widely distributed in arid and semi-arid regions of the world. The invasion inflicts varying degrees of ecological implications, albeit certain socio-economic benefits are being derived by the local community. In Southern India, the vast semi-arid plains lying east of the Western Ghats mountain range, has ideally favored extensive invasion of P.juliflora. In last three decades, the invasion had spread to the pasture and arable lands that are lying disconnected from the mainstream irrigation system. Therefore, in the context of worsening food security, ecological imbalance, increasing soil degradation and the climate change, the prospects of converting the P.juliflora invaded lands to silivicultural/agricultural activity has been envisaged as a viable alternative. In this scenario, present study is an imperative attempt to understand the coexisting vegetation, soil nutrient profile and heavy metal concentrations in the P.juliflora invaded lands at Tiruchirappalli and Pudukkottai regions of Southern India. Composite soil samples were collected from 60 sites (spread across 4800 km2 including urban–rural gradient) at the depths 0 – 10, 10 – 20, and 20–30 cm. The influence of P.juliflora stand density, litter fall, species diversity, soil texture on the soil physico-chemical properties including soil pH, electrical conductivity (EC), available macro nutrients (N, P and K), organic carbon and heavy metals [Fe, Cu, Cd, Cr, Ni, and Pb] were investigated. The results revealed considerable enrichment of macronutrients in the invaded lands, in contrast to non-invaded lands (p < 0.001***). Of the observed attributes, step wise regression indicated stand density and litter fall as prominent factors (R = 0.7903 and 0.6479 respectively) augmenting soil macro nutrients. In the case of heavy metals, observations along the urban–rural gradient indicated comparatively lower concentrations of heavy metals in the P.juliflora invaded lands of urban areas, hinting the possible of bio-sorption capacity of P.juliflora. Overall, the results infer an optimistic note for potential conversion of the P.juliflora invaded lands to silivicultural maneuvers, prioritizing the native flora.
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