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Harvard Forest Data Archive

HF347

Density Anomalies in White Pine at Harvard Forest 2019

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Data

Overview

  • Lead: Elise Miller, Tim Rademacher
  • Investigators: Patrick Fonti, Andrew Richardson, Bijan Seyednasrollah
  • Contact: Information Manager
  • Start date: 2019
  • End date: 2019
  • Status: completed
  • Location: Tom Swamp Tract (Harvard Forest)
  • Latitude: 42.51
  • Longitude: -72.22
  • Elevation: 340 meter
  • Taxa: Pinus strobus
  • Release date: 2020
  • Revisions:
  • EML file: knb-lter-hfr.347.1
  • DOI: digital object identifier
  • EDI: data package
  • DataONE: data package
  • Related links:
  • Study type: short-term measurement
  • Research topic: historical and retrospective studies; physiological ecology, population dynamics and species interactions
  • LTER core area: primary production
  • Keywords: carbon, climate, dendrochronology, pine, tree growth, tree rings, wood
  • Abstract:

    The density of wood is a primary determinant of the amount of carbon sequestered in forests. For boreal and Mediterranean ecosystems, anomalies from the typical intra-annual density increase in radial growth of conifers are predominantly related to drought.

    We took 41 wood samples at breast height, ten additional samples near branches, and seven samples from the top of 41 white pines to determine the spatial distribution of density anomalies throughout the stem. We measured the ring width, density anomaly presence, position within a ring, and arc of density anomalies at multiple heights.

    Even in a mesic forest density anomalies in white pine are predominantly occurring during drier growing seasons. Moreover, we examined the spatial extent of density anomalies within the stems of white pines and discovered density anomalies are more likely to occur near branches, at the top of the tree, and in wider rings. Furthermore, the position of the density anomalies within the rings was remarkably consistent with the anomalies occurring roughly 80% into the fully formed ring at all heights for high-frequency years only as well as all years

    Density anomalies seem to be triggered by exogenous factors but their distribution within the stem varies along endogenous gradients, thus better understanding these systematic anomalies can help us to understand how wood formation has reacted and will respond to the environment and changes therein.

  • Methods:

    Sample site and preparation

    To study the formation of density anomalies, we sampled 41 white pines in Tom Swamp at Harvard Forest in Petersham, Massachusetts.

    We sampled in June and July 2019 and excluded the 2017, 2018, and 2019 growth increments, because while the trees had regenerated naturally after a clear-cut in 1990, some of them were girdled and compressed in 2017, affecting their radial growth thereafter. All trees occupied a codominant canopy position and their surroundings did not show signs of recent disturbance. The trees ranged from 15 to 26 years of cambial age at breast height, had a single straight bole for at least 4 m above the root collar, and had no obvious signs of recent damage. They varied between 8 and 14 meters in height and between 15 and 25 cm in breast height diameter.

    We collected increment cores from all 41 trees at breast height (ca. 1.5m) and for a subset of ten trees near the next branch whorl above breast height using a 5.1mm three-threaded Haglöf standard increment borer (Långsele, Sweden). All of the increment cores went through the entire bole, which gave us two opposing series of radial growth. To study the longitudinal and circumferential distribution of density anomalies, we cut down a subset of seven trees and took cross-sections at breast height and in the stem section that grew in 2010 towards the top of the tree. After mounting the cores, we sanded the cores and cross-sections with incrementally finer sandpaper (e.g., 80 to 8000). We then scanned the cores and cross-sections using an Epson Perfection V600 Photo Scanner (Long Beach, California) at 2400 dpi.

    Identification and measurement of ring widths and density anomaly position

    After crossdating the cores and cross-sections, we visually recorded the presence of density anomalies in each growth ring. Density anomalies were easily identifiable as a relatively dark band that interrupted a growth increment. For measurements of ring width and position of the density anomalies, we used the self-developed and open source Tree Ring Image and Analysis Database (http://phenocam.nau.edu/TRIAD/) platform. We used the open source GNU Image Manipulation Program v2.8 (https://www.gimp.org/) to measure the arc of density anomalies in scans of cross-sections from breast height and the top of the tree.

  • 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:

    Miller E, Rademacher T. 2020. Density Anomalies in White Pine at Harvard Forest 2019. Harvard Forest Data Archive: HF347.

Detailed Metadata

hf347-01: density anomaly data

  1. year: year of the annual growth increment
  2. tree.id: identifying number of the tree
  3. study: study that the tree was selected for
  4. alternative.id: identifying number for the study that the tree was originally selected for
  5. samplelocation: tree location
  6. ringwidthbh.1: first ring width from an increment core taken at breast height (unit: millimeter / missing value: NA)
  7. ringwidthbh.2: second ring width from an increment core taken at breast height (unit: millimeter / missing value: NA)
  8. ringwidth2010.1: firest ring width measured from the 2010 cookie (unit: millimeter / missing value: NA)
  9. ringwidth2010.2: second ring width measured from the 2010 cookie (unit: millimeter / missing value: NA)
  10. ringwidthnearbranch.1: first ring width measured from an increment core taken near a branch whorl (unit: millimeter / missing value: NA)
  11. ringwidthnearbranch.2: second ring width measured from an increment core taken near a branch whorl (unit: millimeter / missing value: NA)
  12. apicalgrowth: apical growth of the annual growth increment between branch whorls (unit: millimeter / missing value: NA)
  13. apicalgrowth.l: apical growth of the annual growth increment between branch whorls from the smaller leader (unit: millimeter / missing value: NA)
  14. dabh.1: number of density anomalies in first profile of breast height increment core (unit: number / missing value: NA)
  15. dabh.2: number of density anomalies in second profile of breast height increment core (unit: number / missing value: NA)
  16. da2010.1: number of density anomalies in first profile of 2010 cookie (unit: number / missing value: NA)
  17. da2010.2: number of density anomalies in second profile of 2010 cookie (unit: number / missing value: NA)
  18. dabranch.1: number of density anomalies in first profile of branch increment core (unit: number / missing value: NA)
  19. dabranch.2: number of density anomalies in second profile of branch increment core (unit: number / missing value: NA)
  20. positiondabh.1.1: distance of density anomaly in from ring boundary of the previous winter in first profile (unit: millimeter / missing value: NA)
  21. positiondabh.1.2: distance of density anomaly in from ring boundary of the previous winter in first profile if there is a second density anomaly (unit: millimeter / missing value: NA)
  22. positiondabh.2.1: distance of density anomaly in from ring boundary of the previous winter in second profile (unit: millimeter / missing value: NA)
  23. positiondabh.2.2: distance of density anomaly in from ring boundary of the previous winter in second profile if there is a second density anomaly (unit: millimeter / missing value: NA)
  24. percentagedabh.1.1: location of density anomaly as percent of the ring width (unit: dimensionless / missing value: NA)
  25. percentagedabh.1.2: location of density anomaly as percent of the ring width (unit: dimensionless / missing value: NA)
  26. percentagedabh.2.1: location of density anomaly as percent of the ring width (unit: dimensionless / missing value: NA)
  27. percentagedabh.2.2: location of density anomaly as percent of the ring width (unit: dimensionless / missing value: NA)
  28. positiondabranch.1.1: distance of density anomaly in from ring boundary of the previous winter in first profile in the branch core (unit: millimeter / missing value: NA)
  29. positiondabranch.1.2: distance of density anomaly in from ring boundary of the previous winter in first profile if there is a second da (unit: millimeter / missing value: NA)
  30. positiondabranch.2.1: distance of density anomaly in from ring boundary of the previous winter in second profile in the branch core (unit: millimeter / missing value: NA)
  31. positiondabranch.2.2: distance of density anomaly in from ring boundary of the previous winter in second profile if there is a second da in the branch core (unit: millimeter / missing value: NA)
  32. percentagedabranch.1.1: location of density anomaly as percent of the ring width (unit: dimensionless / missing value: NA)
  33. percentagedabranch.1.2: location of density anomaly as percent of the ring width (unit: dimensionless / missing value: NA)
  34. percentagedabranch.2.1: location of density anomaly as percent of the ring width (unit: dimensionless / missing value: NA)
  35. percentagedabranch.2.2: location of density anomaly as percent of the ring width (unit: dimensionless / missing value: NA)
  36. positionda2010.1.1: distance of density anomaly in from ring boundary of the previous winter in first profile (unit: millimeter / missing value: NA)
  37. positionda2010.1.2: distance of density anomaly in from ring boundary of the previous winter in first profile if there is a second da (unit: millimeter / missing value: NA)
  38. positionda2010.2.1: distance of density anomaly in from ring boundary of the previous winter in second profile (unit: millimeter / missing value: NA)
  39. positionda2010.2.2: distance of density anomaly in from ring boundary of the previous winter in second profile if there is a second (unit: millimeter / missing value: NA)
  40. percentageda2010.1.1: location of density anomaly as percent of the ring width (unit: dimensionless / missing value: NA)
  41. percentageda2010.1.2: location of density anomaly as percent of the ring width (unit: dimensionless / missing value: NA)
  42. percentageda2010.2.1: location of density anomaly as percent of the ring width (unit: dimensionless / missing value: NA)
  43. percentageda2010.2.2: location of density anomaly as percent of the ring width (unit: dimensionless / missing value: NA)
  44. bhsection: id number of the bh section
  45. 2010section: id number of the 2010 section
  46. arcbh: arc of the density anomaly in the breast height cookie (unit: degree / missing value: NA)
  47. arc2010: arc of the density anomaly in the 2010 cookie (unit: degree / missing value: NA)
  48. oldestannualincbh: oldest ring in the breast height increment
  49. pithinimagebh: pith in the image
    • TRUE: pith is in the image
    • FALSE: pith is not in the image
  50. cambialagebh: cambial age at breast height (unit: number / missing value: NA)
  51. oldestannualincbranch: oldest ring in the branch increment
  52. pithinimagebranch: pith in the image
    • TRUE: pith is in the image
    • FALSE: pith is not in the image
  53. cambialagebranch: cambial age at branch (years) (unit: number / missing value: NA)
  54. woodagebh: wood age at breast height (latest year minus the earliest year) (years) (unit: number / missing value: NA)
  55. woodagebranch: wood age at branch (years) (unit: number / missing value: NA)
  56. woodage2010: wood age in the 2010 cross section (years) (unit: number / missing value: NA)

hf347-02: R code density anomaly analysis

  • Compression: zip
  • Format: R code
  • Type: R code