Himalayan Hotspot with Alien Weeds: A Case Study of Biological Spectrum, Phenology, and Diversity of Weedy Plants of High Altitude Mountains in District Kupwara of J&K Himalaya, India

Abstract

Authentic certification, documentation, and ecological characterization of weed flora are of paramount importance for future studies that would help to formulate strategies for their management and conservation. Alien plants used to pose severe threats to ecosystems, and qualitative studies on weed flora in many interior regions of the Himalaya are still scarce. Patterns of species diversity, biological spectrum, and phenology of weeds growing in the Himalayas with invasive nature were investigated from 2017 to 2019 in thirty-eight localities of interior Kupwara district of Kashmir Himalaya from different agroecological zones. A hierarchical cluster analysis using the presence or absence data of flowering among plant species was performed and a complex Heatmap package was used. Data collected revealed a total of 158 plant species belonging to 115 genera and 35 families identified from a high altitude district Kupwara in India. The species distribution pattern across the families was unequal, with three families share more than half of the species documented, while fifteen families were monotypic. The family Asteraceae, Poaceae, and Brassicaceae were the most important weeds in terms of species abundance and species richness. Asteraceae represented by 35 species, as the dominant family followed by Poaceae with 19 species, and Brassicaceae by 14 species. In terms of functional trait diversity, the annual growth form was dominant over other forms such perennial or biannual. The phytogeographical analysis revealed that the maximum 91 species collected were native, while a minimum of 67 species reported as alien. Of the alien species, 25 were invasive, 35 naturalized, and 7 casual. The biological spectrum revealed the dominance of therophyte life form indicating the disturbed vegetation. The phenological spectrum revealed the maximum flowering period of weeds is between April and September where about 73% of species were observed in full bloom. This research adds an important way to the basic information of biodiversity patterns in the Himalayas and constitutes baseline data for the planned implementation of conservation. The outcomes also provide the baseline information on alien weeds, their invasive nature as well as in for better prediction of phenological shifts associated with these species due to contemporary climate change. It also would help to design conservation and management plans for threatened or otherwise important species for future implementation.