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Harvard Forest Symposium Abstract 2015

  • Title: Patterns and composition across a 35 hectare temperate forest plot
  • Primary Author: David Orwig (Harvard Forest)
  • Additional Authors: Jason Aylward (Harvard Forest)
  • Abstract:

    To investigate the forest dynamics across a larger range of scales in which many processes operate, Harvard Forest (HF) researchers, with assistance from the Center for Tropical Forest Science (CTFS) and the Smithsonian Institute’s Forest Global Earth Observatory (ForestGEO), recently completed an initial census of all woody stems within a 35 ha plot located at the Harvard Forest. The HF MegaPlot is part of a global array of large-scale plots established by CTFS whose goals are to increase sampling efforts into temperate forests to explore ecosystem processes beyond population dynamics and biodiversity. The geography and size of the HF MegaPlot (500 m x 700 m) is designed to include a continuous, expansive, and varied natural forest landscape. The strategic plot location will yield opportunities for the study of forest dynamics and demography while capturing a large amount of existing NSF funded LTER (Long Term Ecological Research) science infrastructure (e.g. eddy flux towers, gauged sections of a small watershed, existing smaller permanent plots) and a century of observations and studies. The HF MegaPlot will enable an integrated study of ecosystem processes (e.g., biogeochemistry, hydrology, carbon dynamics) and forest dynamics by melding the past with current and future forest research.

    The HF MegaPlot has 108,131 live stems ≥ 1cm dbh, representing 77,125 individuals, and an additional 8,095 dead stems ≥ 5 cm dbh. Remarkably, among the 51 woody species, only 1 invasive species (Frangula alnus) was recorded in the plot indicating the current naturalness of our study forest. Mean live stem density was 2204 ha-1, and three species (Tsuga canadensis, Acer rubrum, and Ilex verticillata) comprised 56% of all stems. Overall, 78% of the stems within the plot were < 10 cm dbh, and were dominated by shrubs such as I. verticillata, Vaccinium corymbosum, and Kalmia latifolia. Live tree basal area averaged 42.16 m2ha-1, of which 84% was represented by T. canadensis (14.0 m2ha-1), Quercus rubra ( 9.6 m2ha-1), A. rubrum ( 7.2 m2ha-1) and Pinus strobus (4.4 m2ha-1) . Species distribution patterns broadly followed topographic features and past land use history. The HF ForestGEO is poised for a significant transformation in the next few years due to the invasive insect (Adelges tsugae), which has recently infested the plot and threatens most T. canadensis stems. The plot data will make an excellent comparison with other temperate hardwood plots worldwide and will integrate well with ongoing NSF-funded LTER and NEON (National Ecological Observation Network) studies.

  • Research Category: Large Experiments and Permanent Plot Studies

  • Figures:
  • All stems above 1 cm.pdf