Temporal changes in biomass production across different plant communities in alpine meadows of Tungnath, Garhwal Himalaya

Abstract

We studied temporal changes in biomass and net primary productivity of alpine grasslands at Tungnath in Garhwal Himalaya. Five different communities with similar elevations were taken for investigation. The above-ground biomass samples were harvested as close to the ground as possible. Similarly, below-ground biomass samples were collected from harvesting monoliths (25 x 25 x 30 cm). Aboveground net primary production was determined as the sum of positive changes in biomass and belowground net primary production was calculated as the difference between peak belowground biomass and preceding minimum biomass. The live shoot biomass increased from May till September in all communities except Trachydium roylei and Polygonum, which peaked in August. The dead shoot and litter biomass first decreased and peaked in all communities in October. Belowground biomass first decreased and then increased towards the end of the growing season. The belowground to aboveground biomass ratio ranged between 0.61-3.08. The aboveground net productivity ranged between 454.8-294.3 g m-2, and the belowground net productivity ranged between 346.3-102.4 g m-2.