uid=HFR,o=lter,dc=ecoinformatics,dc=org all public read doi:10.6073/pasta/3c30eab2f00a2bc4ae0f920e98c47abd Tad Zebryk David Foster https://orcid.org/0000-0003-1171-3762 2023 English

The post-glacial history of two adjacent sites in the Harvard Forest, a 10-ha swamp (Black Gum Swamp) and a 0.006-ha hollow (Hemlock Hollow) in a Tsuga canadensis forest were investigated using pollen analysis. The sites were selected in order to contrast the regional vegetation history revealed from the swamp sediments with the local history of the Tsuga forest reconstructed from the Hollow sediments. Specific objectives were (1) to document the natural and anthropogenic disturbance history, (2) to examine the long-term vegetation dynamics of the two sites resulting from environmental change, species migration, and disturbance, especially with respect to Tsuga, and (3) to contrast the pre-and post-settlement vegetation and environments. The Swamp and Hollow cores contain continuous sediment records covering the past 12,300 and 9500 yr, respectively. Regional vegetation changes are delimited in six pollen zones: I, Herb zone, (12500 – 11800 yr BP); II, Picea zone (11800 –9350 yr BP) III, Pinus-Quercus zone (9350-8350 yr BP); IV, Tsuga-northern hardwoods zone (8350-1750 yr BP); V, Tsuga-Castanea-hardwoods zone (1750-200 yr BP); and VI, Post-settlement zone (200 yr BP-present). No disturbances are detected in the periods of tundra or boreal vegetation from 12500 to 8350 yr BP. Since 8350 yr BP three distinct disturbance processes are detectable: (1) fires recorded in discrete charcoal horizons, (2) the apparent pathogenic decline of Tsuga (4700-3500 yr BP) and the blight of Castanea (~1915 A.D.), and (3) post-settlement forest cutting, burning, land clearance an cultivation (1750 A.D. to present).

fires paleoecology pollen vegetation dynamics wetlands LTER controlled vocabulary disturbance human-environment LTER core area Harvard Forest HFR LTER USA HFR default

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.

Creative Commons Zero v1.0 Universal https://spdx.org/licenses/CC0-1.0.html CC0-1.0 https://harvardforest.fas.harvard.edu/exist/apps/datasets/showData.html?id=hf100 Prospect Hill Tract (Harvard Forest). Coordinates based on WGS84 datum. -72.179720 -72.179720 +42.539330 +42.539330 355 355 meter -10500 2000 genus Acer species rubrum red maple species saccharum sugar maple genus Betula birch genus Castanea chestnut genus Fraxinus ash genus Nyssa black gum genus Picea spruce genus Pinus pine genus Populus aspen genus Quercus oak genus Tsuga species canadensis hemlock complete Information Manager Harvard Forest

324 North Main Street Petersham MA 01366 USA

(978) 724-3302 hf-im@lists.fas.harvard.edu Harvard Forest

324 North Main Street Petersham MA 01366 USA

(978) 724-3302 (978) 724-3595 https://harvardforest.fas.harvard.edu

Morphometric maps of the sites were constructed by probing with thin steel rods across a 25-m grid at Black Gum Swamp (BGS) and 1-m grid at Hemlock Hollow (HH). A total of 500 cm of sediment core length was obtained with a 5 cm diameter Russian corer from the deepest part of the BGS basin, and 72 cm of sediment was recovered at HH with a piston corer. Cores were sub-sampled volumetrically for pollen and charcoal analysis at measured stratigraphic intervals, spiked with eucalyptus-glycerin solution and processed using the method of Faegri and Iverson (1975). A minimum of 300 arboreal grains was identified at each level. Charcoal (greater than 15 μm longest dimension) was tallied for the entire core at BGS and the last 3000 yr at HH using the point-intercept method (Clark 1982). Organic carbon content was determined by loss-on-ignition at 550° C at 10-cm intervals at BGS and 1-cm intervals at HH (Dean 1974). The chronostratigraphy at HH is based on an accelerator 14C date of the basal sediments and pollen-stratigraphic correlation with the dated BGS core. Pollen data from each site were ordinated separately using detrended correspondence analysis (DECORANA; Hill and Gauch 1980) to analyze relationships among species and samples.

Harvard Forest

324 North Main Street Petersham MA 01366 USA

(978) 724-3302 (978) 724-3595 https://harvardforest.fas.harvard.edu https://ror.org/059cpzx98 pointOfContact The Harvard Forest Long-Term Ecological Research (LTER) program examines ecological dynamics in the New England region resulting from natural disturbances, environmental change, and human impacts. National Science Foundation LTER grants: DEB-8811764, DEB-9411975, DEB-0080592, DEB-0620443, DEB-1237491, DEB-1832210. hf100-01-age.csv age model hf100-01-age.csv 254 51d3636cb3148a252cc93cd0cb92009d 1 \r\n column , https://harvardforest.fas.harvard.edu/data/p10/hf100/hf100-01-age.csv site site name BGS Black Gum Swamp HH Hemlock Hollow depth depth in the sediment column centimeter 0.1 real NA missing value thickness thickness of the measured sample centimeter 1 whole NA missing value age age before present (years) number 1 whole NA missing value 15 hf100-02-pollen.csv pollen hf100-02-pollen.csv 187068 76a11e7eaa954b1d3c74ebcdc689588e 1 \r\n column , https://harvardforest.fas.harvard.edu/data/p10/hf100/hf100-02-pollen.csv site site name BGS Black Gum Swamp HH Hemlock Hollow taxa pollen taxa pollen taxa depth depth in the sediment column centimeter 0.1 real NA missing value count number of pollen grains number 1 whole NA missing value 8800 historical community paleological