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Harvard Forest Data Archive

HF119

Ant Diversity and Vegetation Composition in Hemlock Removal Experiment at Harvard Forest 2006

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Data

Overview

  • Lead: Aaron Ellison, Sydne Record
  • Investigators: Alexander Arguello
  • Contact: Aaron Ellison
  • Start date: 2006
  • End date: 2006
  • Status: completed
  • Location: Simes Tract (Harvard Forest)
  • Latitude: +42.47 to +42.48
  • Longitude: -72.22 to -72.21
  • Elevation: 200 to 240 meter
  • Taxa: Hymenoptera, Tsuga canadensis
  • Release date: 2019
  • Revisions:
  • EML file: knb-lter-hfr.119.17
  • DOI: digital object identifier
  • Related links:
  • Study type: long-term measurement
  • Research topic: large experiments and permanent plot studies; physiological ecology, population dynamics and species interactions
  • LTER core area: populations, disturbance
  • Keywords: abundance, ants, habitats, hemlock, hemlock woolly adelgid, species composition
  • Abstract:

    Ants comprise a considerable amount of animal biomass in terrestrial ecosystems and play major roles in ecological processes ranging from seed dispersal to soil turnover. Invasion by the hemlock woolly adelgid will transform late-successional hemlock forests into earlier successional mixed hardwood-white pine forests or red-maple wetlands. Understanding how ant assemblages vary in different habitat types allows for predictions of how hemlock decline could alter the composition of ant assemblages, with implications for a wide range of ecosystem processes. An ongoing study at the Simes Tract of Harvard Forest is documenting the effects of invasion and land-use history on ant biodiversity. Surveys from 2003 to 2005 focused on ant structure in hemlock and hardwood microhabitats in the Harvard Forest Hemlock Removal Experiment, in which hemlock forest response to deforestation by the hemlock woolly adelgid (Adelges tsugae) and to selective logging is being examined (Ellison et al. 2005). In the summer of 2006, we surveyed a greater range of microhabitat types with two objectives. First, to collect rare or elusive species in hemlock and hardwood stands that may have gone uncollected in previous years. Second, to sample forest communities not included in previous years - white pine, swamp, and rocky slope - for ant species unique to these microhabitats. We found fourteen newly documented species of ants in the Simes Tract - nine of which were in an open, swamp. Aphaenogaster rudis and Camponotus pennsylvanicus were the only ant species found in all microhabitat types. In a canonical correspondence analysis, A. rudis and C. pennsylvanicus were associated most strongly with hemlock stands and low species richness of understory plants.

  • Methods:

    Overview

    Within the Simes tract, we sampled 100-m transects at eight sites with the following microhabitats: two sites each of hemlock, white pine, and hardwood overstories; a swamp site; and a rocky-slope. At the swamp site, the transect length was only 50 m due to geographical constraints. At each transect we sampled ants and vegetation. Ants were sampled twice at each site between June and August 2006 from pitfall traps, baits, sieved litter, and hand-collections. Pitfall traps were 95mm-diameter plastic cups buried even with the substrate surface. Traps were filled with 20-mL soapy water and left to accumulate ants for 48 hours during dry weather. Trap contents were collected and fixed in the field in 95% EtOH. Following collection of the pitfall traps, bait stations (50 mg Pecan Sandies cookies) were set up at each sample point. Baits were set out on white index cards during the middle of the day for one hour after which ants were collected with a suction aspirator. Litter-dwelling ants were extracted from three 1-L leaf litter samples per transect. We also searched for and hand-collected ants for 1 person-hour throughout each site, looking under rocks, on low-growing vegetation, and in the leaf litter. All vegetation sampling was performed in mid-July during the height of the growing season. At 5-m intervals along the transect, the number of stems of all herbs and shrubs was recorded within 50 x 50-cm quadrats centered on each pitfall location. In the first week of September 2006, we took hemispherical canopy photos along the transects at 0m, 50m and 100m using a Nikon 8mm fisheye lens and F-3 camera. At the swamp site, we took hemiphotos at 0m, 25m, and 50m since that transect was only 50 m long. We measured the basal area of all trees greater than 5-cm diameter at breast height (DBH) within 5-m of each 100-m transect.

    Transect Information

    Transect Information (8 transects total of 100 m in length unless otherwise noted). Compass declination set at 15 deg. Transect 1. Hemlock overstory. Transect located in the northwest corner of the Simes Tract running west of and adjacent to a small stream. Transect runs at 354.5 deg. Transect 2. Hemlock overstory. Transect located in the northwest corner of the Simes Tract southeast of Transect 1 and south of wetland. Transect runs at 203.5 deg. Transect 3. Hardwood overstory. Transect located between Hemlock Removal Experiment plots 7 and 6. Transect runs at. Transect 4. White pine and Hemlock Swamp. Transect located in northwest corner of the Simes Tract on the western side of the wetland. Transect runs at 176 deg. Transect is 50 m in length. Transect 5. Hardwood overstory on rocky slope. Transect located northeast of Hemlock Removal Experiment Plot 3 running west of and adjacent to a ravine. Transect runs at 171 deg. Transect 6. Hardwood overstory. Transect parallels a stone wall and is located west of skid road leading to Hemlock Removal Experiment Plots 1, 2, and 3. Transect runs at 86.5 deg. Transect 7. White pine overstory. Transect located in south central portion of the Simes Tract west of a stream and the jeep road that runs perpendicular to the main parking area off of Dugway Rd. Transect is located within a stone wall foundation. Transect runs at 332.5 deg. Transect 8. White pine overstory. There are two transects running parallel to one another and 6 m apart. Transects located in south central portion of the Simes Tract running parallel to Dugway Rd. Transects run at 24.5 deg.

  • Use:

    This dataset is released to the public under Creative Commons license CC BY (Attribution). Please keep the designated contact person informed of any plans to use the dataset. Consultation or collaboration with the original investigators is strongly encouraged. Publications and data products that make use of the dataset must include proper acknowledgement.

  • Citation:

    Ellison A, Record S. 2019. Ant Diversity and Vegetation Composition in Hemlock Removal Experiment at Harvard Forest 2006. Harvard Forest Data Archive: HF119.

Detailed Metadata

hf119-01: ants

  1. date: date of collection
  2. transect: transect number
  3. distance: location in meters along transect (unit: meter / missing value: NA)
  4. trap.no: the number of the trap within the transect. Twenty traps total per transect.
  5. trap.type: the method of collection
    • Pitfall: pitfall
    • 1 hour bait: one hour bait
    • Hand: hand
    • 15 min bait: fifteen minute bait
    • Litter: litter samples conducted at 30, 60, and 90 meter marks of the transect. Transect 8 had litter samples conducted at 0, 25, and 50 meter marks.
  6. genus: genus of the ant collected
  7. species: species of the ant collected
  8. spec.code: species code
  9. no.ants: number of ants collected of that particular species within the trap (unit: number / missing value: NA)
  10. ref.no: reference number
  11. caste: the role of the ant collected within the colony

hf119-02: overstory

  1. date: date of collection
  2. transect: transect number (all trees measured within 5m of transect (2.5 m either side of transect))
  3. genus: genus of the tree sampled
  4. species: species of the tree sampled
  5. spec.code: species code
  6. dbh: diameter at breast height of tree sampled (unit: centimeter / missing value: NA)
  7. condition: condition of tree
    • 0: alive
    • 1: dead
  8. coppiced: coppiced
    • 0: tree is not coppiced
    • 1: tree is coppiced
  9. basal.area: basal area (unit: squareCentimeters / missing value: NA)

hf119-03: understory

  1. date: date of collection
  2. transect: transect number
  3. distance: location in meters along transect (unit: meter / missing value: NA)
  4. trap.no: the number of the trap within the transect that the 50 cm x 50 cm sampling quadrat was centered around. Twenty traps total per transect.
  5. genus: genus of the plant sampled
  6. species: species of the plant sampled
  7. spec.code: species code
  8. no.stems: number of stems sampled of that particular species within the 50 cm x 50 cm quadrat (unit: number / missing value: NA)

hf119-04: canopy photos

  1. transect: transect number (1-8)
  2. distance: location along transect in meters (unit: meter / missing value: NA)
  3. gsf: estimated proportion of global radiation (direct plus diffuse) under a plant canopy relative to that in the open (unit: number / missing value: NA)
  4. dsf: estimated proportion of direct solar radiation reaching a given location, relative to that in a location with no sky obstruction (unit: number / missing value: NA)
  5. isf: estimated proportion of diffuse solar radiation reaching a given location, relative to a location with no sky obstruction (unit: number / missing value: NA)
  6. tot.be: estimated total radiation below the canopy (unit: megajoulePerMeterSquaredPerYear / missing value: NA)
  7. dir.be: estimated direct radiation below the canopy, corrected for interception surface orientation (unit: megajoulePerMeterSquaredPerYear / missing value: NA)
  8. lai: estimated leaf area index for the entire canopy (unit: number / missing value: NA)
  9. gnd.cover: estimated overall fraction of ground covered by canopy (unit: number / missing value: NA)
  10. lai.dev: estimated uniformity of the canopy across the image (unit: number / missing value: NA)
  11. threshold: user-specified value used to classify the image into black and white pixels (unit: number / missing value: NA)

hf119-05: transect information

  1. transect: transect number (1-8)
  2. length.m: length of the transect in meters (50 or 100) (unit: meter / missing value: NA)
  3. latitude.start: latitude of the starting point of the transect (unit: degree / missing value: NA)
  4. longitude.start: longitude of the starting point of the transect (unit: degree / missing value: NA)
  5. direction: direction the transect runs (degrees west of north; declination set at 15 degrees) (unit: degree / missing value: NA)
  6. vegetation: dominant canopy vegetation