2021, VOLUME 8 ISSUE 1Pages: 50-62
A preponderance of alien species in Delhi NCR of western Uttar Pradesh: possible impacts on ecosystem
Amit K. Tripathi*, Jyoti K. Sharma and Mohd Ahmad
*Center for Environmental Sciences & Engineering, School of Natural Sciences, Shiv Nadar University, Greater Noida, Uttar Pradesh, India
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The present study catalogued the alien species of parts of Delhi NCR, western Uttar Pradesh, India concerning their possible impacts on biodiversity and ecosystem. Altogether 93 alien plant species belonging to 69 genera and 28 families were identified including two new species record to this region. Of the 93 alien species, about 94% (87 species) have been enlisted as invasive species in Uttar Pradesh and Delhi NCR by different authors. Surprisingly, the study enlisted more than 50% aliens invasive of entire Uttar Pradesh and 90% of the total alien flora of Delhi. Among the alien species, dicots comprised of 83 species and 10 species to monocots. Asteraceae was the most dominant family with 14 alien species followed by Amaranthaceae and Fabaceae (10 species each), Malvaceae (8 species), Convolvulaceae and Euphorbiaceae (7 species each), Solanaceae (6 species) and Poaceae (5 species). Genera such as Alternanthera, Euphorbia, and Ipomoea had the highest number of alien species (4 species each) followed by Corchorus and Indigofera (3 species each). The largest number of species (72%) were of American origin, followed by African (14%), European (5%), Mediterranean (4%) and Asian (2%). The herbaceous plants dominated with 78 alien species whereas trees were least dominant with only two alien species. Being herbaceous, numerous plant species showed seasonality in their occurrence and were recorded in a specific season. Besides their harmful impacts on local biodiversity and ecosystem in general, several alien species were found to have potent medicinal properties and used in folk medicines. A high degree of disturbances due to several developmental activities including land use/land cover changes in the recent past could be one of the reasons for the preponderance of alien species in the study area. A discrepancy in reporting the nativity of some alien species are also highlighted.