Physiochemical Response of the Lichen genus Everniastrum as Bioindicator of Ambient Air Nitrogen Deposition along with an Elevation Gradient in a Temperate-alpine Habitat of Western Himalaya

Abstract

The high elevation habitats of the Himalayas in the past few decades are experiencing intense land
use changes due to tourism-related anthropogenic activities. These habitats receive moderate to
higher deposition of Nitrogen through vehicular, agricultural practices, and other urban exhausts.
Nitrophobic lichens of the family Parmeliaceae largely populate the high elevation habitats. The
current study explores the capability of the Parmelioid genus Everniastrum as a bioindicator of
nitrogen pollution in a temperate-alpine habitat. The study explored the correlation between the
nitrogen accumulation in the thallus of two common Everniastrum species of the landscape to
the photobiont chlorophyll, carotenoids, and chlorophyll degradation. The study concluded that
one of the species Everniastrum cirrhatum can be an appropriate bioindicator of ambient air N
deposition and can be used in long-term biomonitoring experiments.