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Harvard Forest Data Archive

HF199

Effects of Warming on Tree Species Recruitment at Harvard Forest and Duke Forest since 2009

Related Publications

Data

Overview

  • Lead: Jerry Melillo, James Clark, Jacqueline Mohan
  • Investigators: Frank Bowles, Sarah Butler, Carl Salk, Lindsay Scott, Chelsea Baldino, William Werner
  • Contact: Jerry Melillo
  • Start date: 2009
  • End date: 2011
  • Status: ongoing
  • Location: Prospect Hill Tract (Harvard Forest), Duke Forest (NC)
  • Latitude: +35.87 to +42.53
  • Longitude: -79.98 to -72.19
  • Elevation: 130 to 340 meter
  • Taxa: Acer barbatum (southern sugar maple), Acer rubrum (red maple), Acer saccharum (sugar maple), Betula alleghaniensis (yellow birch), Betula lenta (black birch), Betula populifolia (grey birch), Carya glabra (pignut hickory), Carya ovata (shagbark hickory), Fagus grandifolia (beech), Fraxinus americana (white ash), Ilix vomitoria (yaupon holly), Liquidambar styraciflua (sweet gum), Liriodendron tulipifera (tulip poplar), Magnolia grandiflora (southern magnolia), Magnolia virginiana (sweetbay magnolia), Nyssa sylvatica (black gum), Pinus palustris (longleaf pine), Pinus resinosa (red pine), Pinus strobus (white pine), Pinus taeda (loblolly pine), Quercus alba (white oak), Quercus falcata (southern red oak), Quercus nigra (water oak), Quercus phellos (willow oak), Quercus rubra (red oak), Quercus velutina (black oak), Ulmus americana (american elm)
  • Release date: 2014
  • Revisions:
  • EML file: knb-lter-hfr.199.13
  • 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; regional studies
  • LTER core area: disturbance
  • Keywords: climate change, phenology, recruitment, seedlings, soil warming
  • Abstract:

    Climate change is restructuring forests of the United States, although the details of this restructuring are currently uncertain. Rising temperatures of 2 to 8 deg C and associated changes in soil moisture will shift the competitive balance between species that compete for light and water, changing their abilities to produce seed, germinate, grow, and survive. We are using large scale experiments to determine the effects of warming on the most sensitive stage of species distributions, i.e., recruitment, in mixed deciduous forests in southern New England and in the Piedmont region of North Carolina.

    Two questions organize our proposed research: (1) Might temperate tree species near the "warm" end of their range in the eastern United States decline in abundance during the coming century due to projected warming? and (2) Might trees near the "cool" end of their range in the eastern United States increase in abundance, or extend their range, during the coming 100 years because of projected warming? To explore these questions, we are exposing seedlings to air and soil warming experiments in two eastern deciduous forest sites; one at the Harvard Forest (HF) in central Massachusetts, and the other at the Duke Forest (DF) in the Piedmont region of North Carolina. We focus on tree species common to both Harvard and Duke Forests (such as red, black, and white oaks), those near northern range limits (black oak, tulip poplar), and those near southern range limits (yellow birch, sugar maple). At each site, we plant seeds in common gardens established in temperature-controlled, open-top chambers. The experimental design is replicated and fully factorial and involves three temperature regimes (ambient, +3 deg C and +5 deg C) and two light regimes (closed forest canopy (low light) and gap conditions (high light)). Measured variables include Fall/Spring responses to temperature and mid-Summer responses to low soil moisture.

    This research will advance our understanding of how the abundances and geographic distributions of several important eastern tree species near the cool and warm ends of their ranges will change during the century because of projected warming. Warming-induced changes in eastern tree abundances and distributions have the potential to affect both the quality and quantity of goods and services provided by eastern forests, and will therefore be of importance to society.

  • Methods:

    Design Description

    The experiment has nine chambers in each of two areas: 'shade', in forest understory and in a 'gap' created by clearing a section of the forest. In each area there are three replicates of each temperature treatment (+3 deg C, +5 deg C, ambient) with three additional non-chamber control plots used to control the temperature settings of the heated chambers. The chambers are approximately 5 m long and contain two 1.1 m wide planted strips on either side of a central path. Shade chambers have a wall height of 1.5 m and gap chambers have a wall height of 2.4 m.

    Each experimental chamber has its own ventilating fan and power source, a dedicated data cable for its sensors and, if heated, a control valve, heating coil, and piping loop which connects to the main heated water distribution loops of the heating system. The chamber's sensor suite consists of air and soil thermistors, a soil moisture sensor, a quantum sensor to measure photosynthetically active radiation and a relative humidity sensor. The sensors are monitored and the system is controlled by Campbell Scientific (CSI) data loggers and their associated peripherals.

    Spring Phenology

    The opening of buds and development of leaves in the spring are scored on a scale of 1 (no bud activity) to 6 (fully expanded leaves). These categories are best understood by reference to the pictures in Norby et al. (2003). Spring phenology measurements are taken on a biweekly basis starting prior to budbreak and lasting until 90% of seedlings are at a stage 6.

    Fall Phenology

    Starting in late September, seedlings are monitored using three categories of fall phenology. Start of senescence (S) is the date on which 1/3 of leaves are no longer green. These leaves may have changed color, died, or fallen off, but the key point is that they are visibly incapable of photosynthesis. Leaf drop (LD) is the date on which 2/3 of leaves have died. A plant is listed as mature (M) if it has not reached the S category.

    Monthly census

    Chambers are monitored on a monthly basis from early May till late September for seed germination, survival, and growth.

  • 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:

    Melillo J, Clark J, Mohan J. 2014. Effects of Warming on Tree Species Recruitment at Harvard Forest and Duke Forest since 2009. Harvard Forest Data Archive: HF199.

Detailed Metadata

hf199-01: hf environment

  1. year: year
  2. month: month
  3. day: day of month
  4. time: hour of day
  5. chamber: chamber number (1-12)
  6. treatment: light treatment
    • G: chamber in open gap
    • S: chamber under closed canopy
  7. warming: warming treatment
    • 3: 3 degrees C
    • 5: 5 degrees C
    • A: ambient
    • C: control
  8. AT: air temperature (unit: celsius / missing value: NA)
  9. Q: photosynthetically active radiation (unit: micromolePerMeterSquaredPerSecond / missing value: NA)
  10. Rh: relative humidity (%) (unit: dimensionless / missing value: NA)
  11. SM: volumetric water content (fractional) (unit: dimensionless / missing value: NA)
  12. ST: soil temperature at 5cm depth (unit: celsius / missing value: NA)

hf199-02: hf plant ID

  1. Site: site
    • HF: Harvard Forest
  2. Tag: unique number assigned to each plant that germinates in the chambers. In cases where the same tag number was assigned to multiple individuals, one individual was retroactively given a fractional tag number (ie. if two individuals had tag number 2032, one was changed to 2032.5)
  3. Species: species code. Most ambiguous individuals died before they grew large enough for positive identification.
    • acba: Acer barbatum, southern sugar maple
    • acru: Acer rubrum, red maple
    • acsa: Acer saccharum, sugar maple
    • acun: Acer spp, ambiguous maple
    • beal: Betula alleghaniensis, yellow birch
    • bele: Betula lenta, black birch
    • bepo: Betula populifolia, gray birch
    • bepa: Betula papyrifera, paper birch
    • beun: Betula spp, ambiguous birch
    • cagl: Carya glabra, pignut hickory
    • caov: Carya ovata, shagbark hickory
    • fagr: Fagus grandifolia, beech
    • fram: Fraxinus americana, white ash
    • ilvo: Ilix vomitoria, yaupon holly
    • list: Liquidambar styraciflua, sweetgum
    • litu: Liriodendron tulipifera, tulip tree; tulip poplar
    • magr: Magnolia grandiflora, southern magnolia
    • mavi: Magnolia virginiana, sweetbay magnolia
    • nysy: Nyssa sylvatica, black gum; sour gum
    • pipa: Pinus palustris, longleaf pine
    • pire: Pinus resinosa, red pine
    • pist: Pinus strobus, white pine
    • pita: Pinus taeda, loblolly pine
    • piun: Pinus spp, ambiguous pine
    • prse: Prunus serotina, black cherry
    • prpe: Prunus pensylvanica, pin cherry
    • qual: Quercus alba, white oak
    • qufa: Quercus falcata, southern red oak; Spanish oak
    • quni: Quercus nigra, water oak
    • quph: Quercus phellos, willow oak
    • quru: Quercus rubra, red oak
    • quve: Quercus velutina, black oak
    • quun: Quercus spp, ambiguous oak
    • ulam: Ulmus americana, American elm
    • unkn: Unidentified tree
  4. SeedOrigin: seed origins are nested within species. The use of the same seed origin code for multiple species does not imply the same collection site. Seed origin codes have four parts separated by underscores “_”, indicating the US state of origin, the county of origin, whether it was planted or naturally recruited, and a tracking variable to designate separate seed origins from the same state and county (tracking variables were not assigned for naturally recruited individuals). See the file Seed Origin Data for a full list and additional details. “unkn” indicates that the individual could not be unambiguously assigned a seed origin.
  5. Chamber: chamber number and treatment. G=Gap, S=Closed canopy,.chamber number = 01 to 12, temperature delta (celcius) = 3 degrees, 5 degrees, A (ambient) or C (control).
  6. GermDate: date plant germinated
  7. SpringSeeder: only used for red maple (acru). A value of -1 indicates a germination date occurring before the spring seed crop. All other cases have a value of NA.
  8. CensInDate: only used for individuals observed for the first time well after germination. This is the first date the individual was observed.
  9. DatePlanted: date seed planted
  10. DeathDate: date plant was found dead
  11. CensorDate: date plant was censored - plants censored if they overtop a chamber or significantly shade out other plants
  12. MIA: for plants that disappeared (ie. we never observed them again, but did not find the dead plant either), this is the first date we failed to observe them.

hf199-03: hf growth

  1. Date: date measurement was taken
  2. Species: tree species code (see hf199-02-plant-ID.csv for species definitions)
  3. Tag: unique number assigned to each plant that germinates in the chambers
  4. Chamber: chamber number and treatment. G=Gap, S=Closed canopy,.chamber number = 01 to 12, temperature delta (celcius) = 3 degrees, 5 degrees, A (ambient) or C (control).
  5. SpringPhen: spring phenology, using categories described in Norby et al. 2003 (Global Change Biology 9: 1792-1801)
    • 1: no activity
    • 2: bud swelling
    • 3: buds just opening
    • 4: leaves unfolding
    • 5: leaves unfolded and curled/wrinkled/soft
    • 6: leaves flat and fully developed
    • NA: missing value
  6. FallPhen: fall leaf senescence
    • 0: no senescence
    • 1: one third of leaves have either dropped or are no longer green
    • 2: two thirds of leaves have either dropped or are no longer green
    • 10: no senescence, and the tree is still developing new leaves
    • 11: one third of leaves have either dropped or are no longer green, but other leaves on the tree are still developing
    • 12: two thirds of leaves have either dropped or are no longer green, but other leaves on the tee are still developing
    • NA: missing value
  7. PctHerb: herbivory, visually estimated percent of total leaf area (unit: dimensionless / missing value: NA)
  8. PctLTD: leaf tissue damage, defined as leaf area no longer green for reasons other than fall senescence, visually estimated percent of total leaf area (unit: dimensionless / missing value: NA)
  9. WaterStress: water stress
    • 0: no observable water stress
    • 1: slight wilting observed along edges of leaves
    • 2: significant wilting of leaf tissue, leaf stems are still held near normal angles
    • 3: severe wilting of leaf tissues and significant drooping of leaf stems
    • NA: missing value
  10. Height: height of tree (unit: centimeter / missing value: NA)
  11. Diameter: diameter of tree (unit: centimeter / missing value: NA)

hf199-04: df environment

  1. year: year
  2. times: timestamp. Takes the form of Julian date counted from Jan. 1, 2009 (day 0) plus the hour represented as day fraction. (unit: nominalDay )
  3. month: month
  4. day: day of month
  5. JD: Julian date counted from Jan. 1, 2010 (day 0) (unit: nominalDay )
  6. JD2009: Julian date counted from Jan. 1, 2009 (day 0) (unit: nominalDay )
  7. dayFraction: Hour of the day represented as fraction of the day. Day fractions are thus in increments of 0.0417 (1/24) days. (unit: nominalHour )
  8. chamber: chamber number (1-12)
  9. treatment: light treatment
    • G: chamber in open gap
    • S: chamber under closed canopy
  10. AT: air temperature (unit: celsius / missing value: NA)
  11. Q: photosynthetically active radiation (unit: micromolePerMeterSquaredPerSecond / missing value: NA)
  12. RH: relative humidity (%) (unit: dimensionless / missing value: NA)
  13. SM: volumetric water content (fractional) (unit: dimensionless / missing value: NA)
  14. ST: soil temperature at 5cm depth (unit: celsius / missing value: NA)

hf199-05: seed origin data

  1. Year: year
  2. Species: species code
    • acba: Acer barbatum, southern sugar maple
    • acru: Acer rubrum, red maple
    • acsa: Acer saccharum, sugar maple
    • acun: Acer spp, ambiguous maple
    • beal: Betula alleghaniensis, yellow birch
    • bele: Betula lenta, black birch
    • bepo: Betula populifolia, gray birch
    • bepa: Betula papyrifera, paper birch
    • beun: Betula spp, ambiguous birch
    • cagl: Carya glabra, pignut hickory
    • caov: Carya ovata, shagbark hickory
    • fagr: Fagus grandifolia, beech
    • fram: Fraxinus americana, white ash
    • ilvo: Ilix vomitoria, yaupon holly
    • list: Liquidambar styraciflua, sweetgum
    • litu: Lireodendron tulipifera, tulip tree; tulip poplar
    • magr: Magnolia grandiflora, southern magnolia
    • mavi: Magnolia virginiana, sweetbay magnolia
    • nysy: Nyssa sylvatica, black gum; sour gum
    • pipa: Pinus palustris, longleaf pine
    • pire: Pinus resinosa, red pine
    • pist: Pinus strobus, white pine
    • pita: Pinus taeda, loblolly pine
    • piun: Pinus spp, ambiguous pine
    • prse: Prunus serotina, black cherry
    • prpe: Prunus pensylvanica, pin cherry
    • qual: Quercus alba, white oak
    • qufa: Quercus falcata, southern red oak; Spanish oak
    • quni: Quercus nigra, water oak
    • quph: Quercus phellos, willow oak
    • quru: Quercus rubra, red oak
    • quve: Quercus velutina, black oak
    • quun: Quercus spp, ambiguous oak
    • ulam: Ulmus americana, American elm
    • unkn: Unidentified tree
  3. SeedOriginCode: seed origin codes used in hf199-02-hf-plant-ID. Seed origins are nested within species. The use of the same seed origin code for multiple species does not imply the same collection site. Seed origin codes have four parts separated by underscores “_”, indicating the US state of origin, the county of origin, whether it was planted or naturally recruited, and a tracking variable to designate separate seed origins from the same state and county (tracking variables were not assigned for naturally recruited individuals). See the file Seed Origin Data for a full list and additional details. “unkn” indicates that the individual could not be unambiguously assigned a seed origin.
  4. Notes: additional information about the particular collection