Departmental Seminar at CES on 22 May 2024 at 3:30 pm titled " Effect of grazing in an arid grassland plant community" by Sonali from IISc, Bangalore

Share this story on

Facebook icon Twitter icon
Effect of grazing in an arid grassland plant community
Sonali, IISc, Bangalore
Date & Time: 
22 May 2024 - 3:30pm
Event Type: 
Departmental Seminar
CES Seminar Hall, 3rd Floor, Biological Sciences Building
Before the talk

Arid grasslands are open natural ecosystems covering 19% of Earth’s terrestrial surface. They are grazed by both wild animals and livestock. Grazing based livestock farming is the basis of rural Economy in India, especially in arid regions where agriculture is not economical. However, increasing livestock poses pressure on continuously declining grasslands decreasing native flora and fauna. Hence, my study is focused on the difference in plant community composition, plant diversity, plant traits, and soil nutrients in grazed and long-term ungrazed sites in Chitradurga, Karnataka. I hypothesize that plant diversity and soil C:N ratio will be lower in grazed sites. Plant community composition will differ between the two sites with different plant traits (taller, higher leaf area, higher leaf dry weight in ungrazed). Preliminary results show that plant richness is higher in grazed sites with no significant difference in diversity between the two conditions. Plant species composition in grazed sites were more similar than in the two ungrazed sites. I also found that some plant species differed morphologically between grazed and ungrazed sites. To unravel whether this difference was plasticity or due to evolution, and if it is adaptive, I will carry out common garden experiments followed by reciprocal transplantations. In unfavorable conditions some plants might exist only as seeds. To get a picture of the potential vegetation of the grazed and ungrazed sites, I will compare the plant composition in the soil seed banks, between the long term ungrazed and grazed sites. Because grazers are eating away plants before the reproductive period, I hypothesize that soil seed bank diversity will be lower in grazed than ungrazed sites. Finally, I will conduct a manipulative study, on the short-term effects of grazing on plant communities using grazing exclosures, or a controlled study of plant decomposition rate. Overall, this study will increase our understanding of grassland and grazing ecology in an arid system, while providing a primary database of herbaceous communities in these landscapes. It will provide knowledge about the recovery timing of degraded grazed lands under arid conditions, which is useful to policy makers and conservation biologists planning restoration and conservation programs.