You are here
Harvard Forest Symposium Abstract 2009
- Title: Post-glacial history of vegetation in the Blue Hills, southeastern New Hampshire
- Primary Author: Matts Lindbladh (Swedish University of Agriculture Sciences)
- Additional Authors: Elaine Doughty (Harvard Forest); David Foster (Harvard University); Barbara Hansen (University of Minnesota - Twin Cities); Wyatt Oswald (Emerson College)
- Abstract:
Analyses of pollen, organic content, and charcoal in a sediment core from Little Willey Pond provide new insights into the long-term history of forest ecosystems in the Blue Hills area of southeastern New Hampshire. Late-glacial vegetation was dominated by Picea species and Pinus banksiana. Relatively high percentages of Ambrosia and Poaceae pollen suggest open forest structure, and elevated charcoal concentrations indicate high fire activity. Warmer conditions at the beginning of the Holocene resulted in a dramatic shift from Picea to Pinus strobus; Abies and Quercus species were also present ~11,500-10,000 years ago. Pinus strobus remained dominant ~10,000-8000 years ago, but Picea and Abies declined while Quercus and Tsuga canadensis increased in abundance. Pinus strobus declined and was replaced by Tsuga and Fagus grandifolia as climate became wetter ~8000 years ago. Further reductions in Picea and Abies pollen percentages indicate that those taxa were eliminated from the flora at that time. Tsuga populations declined dramatically at ~5500 years ago, presumably in response to dry climate. Pinus strobus and Quercus species replaced Tsuga from ~5500-3000 years ago, after which they declined and Tsuga returned to its pre-decline levels. Recent sediments feature a rise in Picea pollen percentages, declines in Tsuga and Fagus, and increases in herbaceous taxa marking European settlement and deforestation.
- Research Category:
- Figures: littlewilley_11mar09.pdf
