You are here

Harvard Forest Data Archive


Lake Sediment Pollen from Blood Pond in Dudley MA from 15000 BP to Present

Related Publications



  • Lead: Wyatt Oswald, David Foster
  • Investigators: Elaine Doughty, Edward Faison, Barbara Hansen
  • Contact: Information Manager
  • Start date: -13000
  • End date: 2010
  • Status: completed
  • Location: Blood Pond (Dudley MA)
  • Latitude: +42.08
  • Longitude: -71.9615
  • Elevation: 214 meter
  • Taxa: Betula spp. (birch), Carya spp. (hickory), Fagus spp. (beech), Picea spp. (spruce), Pinus spp. (pine), Quercus spp. (oak), Tsuga spp. (hemlock)
  • Release date: 2011
  • Revisions:
  • EML file: knb-lter-hfr.185.7
  • DOI: digital object identifier
  • EDI: data package
  • DataONE: data package
  • Related links:
  • Study type: paleological
  • Research topic: historical and retrospective studies
  • LTER core area: disturbance, populations
  • Keywords: lakes, paleoecology, pollen, region, sediments, vegetation dynamics
  • Abstract:


    We analysed lake-sediment pollen records from eight sites in southern New England to address: (1) regional variation in ecological responses to post-glacial climatic changes, (2) landscape-scale vegetational heterogeneity at different times in the past, and (3) environmental and ecological controls on spatial patterns of vegetation.


    The eight study sites are located in southern New England in the states of Massachusetts and Connecticut. The sites span a climatic and vegetational gradient from the lowland areas of eastern Massachusetts and Connecticut to the uplands of north-central and western Massachusetts. Tsuga canadensis and Fagus grandifolia are abundant in the upland area, while Quercus, Carya and Pinus species have higher abundances in the lowlands.


    Our analyses revealed a sequence of vegetational responses to climate changes occurring across southern New England during the past 14,000 calibrated radiocarbon years before present (cal yr BP). Pollen assemblages at all sites were dominated by Picea and Pinus banksiana between 14,000 and 11,500 cal yr BP; by Pinus strobus from 11,500 to 10,500 cal yr BP; and by P. strobus and Tsuga between 10,500 and 9500 cal yr BP. At 9500-8000 cal yr BP, however, vegetation composition began to differentiate between lowland and upland sites. Lowland sites had higher percentages of Quercus pollen, whereas Tsuga abundance was higher at the upland sites. This spatial heterogeneity strengthened between 8000 and 5500 cal yr BP, when Fagus became abundant in the uplands and Quercus pollen percentages increased further in the lowland records. The differentiation of upland and lowland vegetation zones remained strong during the mid-Holocene Tsuga decline (5500-3500 cal yr BP), but the pattern weakened during the late-Holocene (3500-300 cal yr BP) and European-settlement intervals. Within-group similarity declined in response to the uneven late-Holocene expansion of Castanea, while between-group similarity increased due to homogenization of the regional vegetation by forest clearance and ongoing disturbances.

    Main conclusions

    The regional gradient of vegetation composition across southern New England was first established between 9500 and 8000 cal yr BP. The spatial heterogeneity of the vegetation may have arisen at that time in response to the development or strengthening of the regional climatic gradient. Alternatively, the differentiation of upland and lowland vegetation types may have occurred as the climate ameliorated and an increasing number of species arrived in the region, arranging themselves in progressively more complex vegetation patterns across relatively stationary environmental gradients. The emergence of a regional vegetational gradient in southern New England may be a manifestation of the increasing number of species and more finely divided resource gradient.

  • Methods:

    We collected sediment cores from three lakes in eastern and north-central Massachusetts (Berry East, Blood and Little Royalston Ponds). Pollen records from those sites were compared with previously published pollen data from five other sites. Multivariate data analysis (non-metric multi-dimensional scaling) was used to compare the pollen spectra of these sites through time.

  • Use:

    This dataset is released to the public under Creative Commons CC0 1.0 (No Rights Reserved). Please keep the dataset creators informed of any plans to use the dataset. Consultation with the original investigators is strongly encouraged. Publications and data products that make use of the dataset should include proper acknowledgement.

  • Citation:

    Oswald W, Foster D. 2011. Lake Sediment Pollen from Blood Pond in Dudley MA from 15000 BP to Present. Harvard Forest Data Archive: HF185 (v.7). Environmental Data Initiative:

Detailed Metadata

hf185-01: pollen

  1. cal.age.bp: calibrated age before present in years (unit: number / missing value: NA)
  2. depth: depth in sediment column (unit: centimeter / missing value: NA)
  3. taxa: name of taxa
  4. count: number of pollen grains or spores of individual (unit: number / missing value: NA)

hf185-02: age

  1. depth: depth in sediment (unit: centimeter / missing value: NA)
  2. cal.age.bp: calibrated age before present (years; present=1950 AD) (unit: number / missing value: NA)
  3. notes: notes and methods of age determination; 210Pb=lead-210 dating; 14C=radiocarbon dating; Euro settlement=determined by rise in abundance of weedy and agricultural taxa
  4. c14: un-calibrated radiocarbon years (unit: number / missing value: NA)
  5. error: analytical error for 14C dates in years (unit: number / missing value: NA)

hf185-03: macrochar

  1. depth: depth in sediment column (unit: centimeter / missing value: NA)
  2. number of macroscopic (greater than 180 microns) per cc (unit: numberPerCentimeterCubed / missing value: NA)

hf185-04: microchar

  1. depth: depth in sediment column (unit: centimeter / missing value: NA)
  2. char.area: area of charcoal pieces greater than 10 and less than 180 microns in length (unit: squareMillimeters / missing value: NA)
  3. exotic.char: number of exotic marker grains encountered during charcoal analysis (unit: number / missing value: NA)
  4. pollen.sum: number of pollen grains and spores of upland taxa encountered during pollen analysis (unit: number / missing value: NA)
  5. exotic.pollen: number of exotic maker grains encountered during pollen analysis (unit: number / missing value: NA)
  6. exotic.added: total number of exotic marker grains added to sample (unit: numberPerCentimeterCubed / missing value: NA)
  7. sed.vol: volume of the sediment samples (unit: centimeterCubed / missing value: NA)