Summary

How to Extract Climate Variability from Tree-Rings

Published: March 09, 2022
doi:

Summary

Tree-ring climate reconstructions can be helpful to better understand past climate variability beyond instrumental records. This protocol shows how to reconstruct past climate using tree rings and meteorological instrumental records.

Abstract

Tree rings have been used to reconstruct climatological variables in many locations around the world. Moreover, tree-rings can provide valuable insights into climatic variability of the last few centuries and, in some areas, several millennia. Despite the important development, that dendrochronology has had in recent decades to study the dendroclimatic potential of a large number of species present in different ecosystems, much remains to be done and explored. In addition to this, in the last few years more people (students, teachers and researchers) around the world are interested in implementing this science to extend the timeline of climate information backwards and understand how climate has changed on scales of decades, centuries or millennia. Therefore, the objective of this work is to describe the general aspects and basic steps needed to conduct a tree-ring climate reconstruction, from site selection and field sampling to laboratory methods and data analysis. In this method’s video and manuscript, the general basis in tree-ring climatic reconstructions is explained so newcomers and students can use it as an available guide into this field of research.

Introduction

Tree rings are fundamental to our understanding of how trees respond to their environment. In addition, because climate affects tree growth, trees serve as environmental gauges recording the temporal variations during their lifespan. Thus, tree rings have been valuable to reconstruct past climates far beyond any instrumental climate record.

Growth processes in roots, stems, branches, leaves, and reproductive strategies in trees are regulated by environmental factors such as water, light, temperature, and soil nutrients1. For example, stems grow radially and the vascular cambium controls radial growth2. The vascular cambium is a meristematic tissue that will actively produce new functional cells such as xylem and bark located at the outer boundary of the stem. Additionally, the vascular cambium is primarily active during seasonal cycles. However, this growth activity can be interrupted during dormancy periods and during particular seasons of the year. This dormancy period usually happens when environmental variables are not optimal (e.g., shorter diurnal cycles, extended drought periods, cold winters, or floods). Furthermore, the growth and dormancy cycles translate in changes in the cambium activity resulting in anatomically distinct concentric boundaries in the stem called tree rings3.

Trees generally produce one tree ring every year since climatic seasonality occurs annually. Thus, tree rings are the visual manifestation of the ecophysiological response of the vascular cambium to the intra-annual climatic conditions during tree growth3. The early cluster of xylem cells formed on a tree ring during the wet season will be characterized by larger cells called earlywood4. In contrast, during the dry season and in response to water scarcity, vascular cambium produces smaller xylem cells (tracheids or vessels) with thicker cell walls called latewood. This variation in anatomical structures is more noticeable in conifers, where the earlywood shows a lighter color than latewood, showing a darker color5. The space between the beginning of the earlywood and the end of the latewood is defined as one tree ring (Figure 8F).

Trees growing on locations with a well-defined rainy and dry season could expect years with a higher or lower amount of precipitation. This variability will lead trees to produce wider rings during wet years and narrower rings during dry years. These temporal patterns of wide and narrow rings can be seen as a barcode. This tree-ring width temporal variation is the basis for applying the process of cross-dating, one of the most critical principles in tree-ring research6. The process of cross-dating is satisfactory when the patterns of wide and narrow rings in all samples are successfully synchronized in time to assign the corresponding year of formation.

In many regions of the world where seasonal climate occurs, the most dominant signal recorded in tree rings is likely related to climate variability7. However, tree rings also contain additional information related to age (young trees grow faster than older ones), competition for resources with surrounding trees, and internal and external disturbances (e.g., mortality events, pest outbreaks, or fire)8. Thus, before attempting to reconstruct past climates using tree ring widths, non-climatic signals need to be removed through several statistical procedures explained in this manuscript.

The main goal of this protocol is to show how to develop a climatic reconstruction based on tree-ring data to understand past climatic variability. Thus, this manuscript will showcase the essential field and laboratory methods such as sampling, sample preparation, cross-dating, and measuring tree-ring widths required to develop a climatic reconstruction. In addition, this protocol will also explain the fundamental statistical analyses used to extract the common variability from tree-ring widths and construct a tree-ring chronology that will be correlated with climatic data. Finally, using a simple linear regression model the protocol will show how to reconstruct past climate using the tree-ring chronology as the predictor variable and the climate data as the predictand.

Protocol

Before the field trips have the permission of the owners, in case of a conservation area, or the corresponding authorities. It is very important that some personnel representing the authority participate in the field work to avoid any problem. 1. Sampling strategy Determining the study area Select the most appropriate sampling area based on climatic information and forest composition (forests can be highly heterogeneous; Figure 1A</…

Representative Results

Following steps 1.1 and 1.2 of the protocol, Pinus lumholtzii B.L. Rob. & Fernald was selected for this study. Among the most important aspects that were considered, a few are as follows: It is a conifer of the genus Pinus with a wide geographical distribution and very few studies from the dendrochronological point of view; it develops in poor sites with rocky outcrops, with low water storage capacity, and its growth is limited by low water and nutritional availability, which causes slow growth rate…

Discussion

Proxy records are natural systems that depend on the weather, which were present in the past and still exist, such as lake and marine sediments, pollen, coral reefs, ice cores, packrat middens, and tree rings, so information can be derived from them24. However, from most climate-sensitive proxies, tree rings represent the proxy with the highest precision and interannual resolution, allowing the dating of climatic and ecological events to the exact year of occurrence, spanning for centuries, and so…

Declarações

The authors have nothing to disclose.

Acknowledgements

The research project was carried out thanks to the financing through the projects CONAFOR-2014, C01-234547 and UNAM-PAPIIT IA201621.

Materials

ARSTAN Software https://www.ldeo.columbia.edu/tree-ring-laboratory/resources/software
Belt Sander Dewalt Dwp352vs-b3 3×21 PuLG For sanding samples
Chain Saw Chaps Forestry Suppliers PGI 5-Ply Para-Aramid https://www.forestry-suppliers.com/Search.php?stext=Chain%20Saw%20Chaps
Chainsaw Stihl or Husqvarna for example MS 660 Essential equipment for taking cross sections samples (Example: 18-24 inch bar)
Clinometer Forestry Suppliers Suunto PM5/360PC with Percent and Degree Scales https://www.forestry-suppliers.com/Search.php?stext=Clinometer
COFECHA Software https://www.ldeo.columbia.edu/tree-ring-laboratory/resources/software
Compass Forestry Suppliers Suunto MC2 Navigator Mirror Sighting https://www.forestry-suppliers.com/Search.php?stext=compass
Dendroecological fieldwork programs Programs where dating skills can be acquired or honed http://dendrolab.indstate.edu/NADEF.htm
Diameter tape Forestry Suppliers Model 283D/10M Fabric or Steel. https://www.forestry-suppliers.com/Search.php?stext=Diameter%20tape
Digital camera CANON EOS 90D DSLR To take pictures of the site and the samples collected (https://www.canon.com.mx/productos/fotografia/camaras-eos-reflex)
Digital camera for microscope OLYMPUS DP27 https://www.olympus-ims.com/es/microscope/dp27/
Electrical tape or Plastic wrap to protect samples uline.com https://www.uline.com/Product/Detail/S-6140/Mini-Stretch-Wrap-Rolls/
Field format There is no any specific characteristic To collect information from each of the samples
Field notebook To take notes on study site information
Gloves For field protection
Haglöf Increment Borer Bit Starter Forestry Suppliers https://www.forestry-suppliers.com/Search.php?stext=Increment%20borer
Hearing protection Forestry Suppliers There is no any specific characteristic https://www.forestry-suppliers.com/Search.php?stext=Hearing%20protection
Helmet Forestry Suppliers There is no any specific characteristic https://www.forestry-suppliers.com/Search.php?stext=Wildland%20Fire%20Helmet
Increment borer Forestry Suppliers Haglof https://www.forestry-suppliers.com/Search.php?stext=Increment%20borer
Large backpacks There is no any specific characteristic Strong backpack for transporting cross-sections in the field
Safety Glasses Forestry Suppliers There is no any specific characteristic https://www.forestry-suppliers.com/Search.php?stext=Safety%20Glasses
Sandpaper From 40 to 1200 grit
Software Measure J2X Version 4.2 http://www.voortech.dreamhosters.com/projectj2x/tringSubscribeV2.html
STATISTICA Kernel Release 5.5 program (Stat Soft Inc. 2000) Statistical analysis program
Stereomicroscope OLYMPUS SZX10 https://www.olympus-ims.com/en/microscope/szx10/
Topographic map, land cover map Obtained from a public institution or generated in a first phase of research
Tube for drawings There is no any specific characteristic Strong tube for transporting samples in the field
Velmex equipment Velmex, Inc. 0.001 mm precision www.velmex.com

Referências

  1. Oliver, C., Larson, B. Brief Notice: Forest Stand Dynamics (Update Edition). Forest Science. 42 (3), 397 (1996).
  2. Dickison, W. C. . Integrative Plant Anatomy. Integrative Plant Anatomy. , (2000).
  3. Tree-Ring and Climate. UCAR Center for Science Education Available from: https://scied.ucar.edu/learning-zone/how-climate-works/tree-rings-and-climate (2022)
  4. Creber, G. T., Chaloner, W. G. Environmental influences on cambial activity. The Vascular Cambium. , 159-199 (1990).
  5. Schweingruber, F. H. . Tree Rings: Basics and Applications of Dendrochronology. , (1988).
  6. Stokes, M. A., Smiley, T. L. . An introduction to tree-ring dating. , (1996).
  7. Speer, J. H. . Fundamentals of tree-ring research. , (2010).
  8. Cook, E. R., Kairiukstis, L. A. . Methods of dendrochronology: applications in the environmental sciences. , (1990).
  9. Maeglin, R. R. Increment Core Specific Gravity of Wisconsin Hardwoods and Minor Softwoods. Department of Agriculture, Forest Service, Forest Products Laboratory. , (1973).
  10. Phipps, R. L. Collecting, preparing, crossdating, and measuring tree increment cores. Water-Resources Investigations Report. U.S. Department of the Interior, Geological Survey. , (1985).
  11. Robinson, W. J., Evans, R. A Microcomputer-Based Tree-Ring Measuring System. Tree-Ring Bulletin. , (1980).
  12. Holmes, R. L. Computer-Assisted Quality Control in Tree-Ring Dating and Measurement. Tree-Ring Bulletin. 43, 51-67 (1983).
  13. Bunn, A. G. A dendrochronology program library in R (dplR). Dendrochronologia. 26, 115-124 (2008).
  14. Cook, E. R. The Decomposition of Tree-Ring Series for Environmental Studies. Tree-Ring Bulletin. 47, 37-59 (1987).
  15. Lorimer, C. G. Methodological considerations in the analysis of forest disturbance history. Canadian Journal of Forest Research. 15 (1), 200-213 (1985).
  16. Nowacki, G. J., Abrams, M. D. Radial-growth averaging criteria for reconstructing disturbance histories from presettlement-origin oaks. Ecological Monographs. 67 (2), 225-249 (1997).
  17. Cook, E. R., Peters, K. The Smoothing Spline: A New Approach to Standardizing Forest Interior Tree-Ring Width Series for Dendroclimatic Studies. Tree-Ring Bulletin. 41, 45-53 (1981).
  18. Cook, E. R. A Time Series Analysis Approach to Tree Ring Standardization. School of Renewable Natural Resources. , (1985).
  19. Briffa, K. R. Interpreting High-Resolution Proxy Climate Data – The Example of Dendroclimatology. Analysis of Climate Variability. , 77-94 (1995).
  20. Biondi, F., Waikul, K. DENDROCLIM2002: A C++ program for statistical calibration of climate signals in tree-ring chronologies. Computers and Geosciences. 30, 303-311 (2004).
  21. Ostrom, C. W. Time Series Analysis (Regression Techniques). Journal of the Royal Statistical Society Series D (The Statistician). , (1991).
  22. Chávez-Gándara, M. P., et al. Reconstrucción de la precipitación invierno-primavera con base en anillos de crecimiento de árboles para la región de San Dimas, Durango, México. Bosque. 38 (2), 387-399 (2017).
  23. Cerano-Paredes, J., Villanueva-Díaz, J., Valdez-Cepeda, R. D., Méndez-González, J., Constante-García, V. Reconstructed droughts in the last 600 years for northeastern Mexico. Revista mexicana de ciencias agrícolas. 2, 235-249 (2011).
  24. Bradley, R. S. . Paleoclimatology: Reconstructing Climates of the Quaternary: Third Edition. , (2013).
  25. Bull, W. B. . Tectonic Geomorphology of Mountains: A New Approach to Paleoseismology. , (2007).
  26. Stahle, D. W., et al. Major Mesoamerican droughts of the past millennium. Geophysical Research Letters. 38 (5), (2011).
  27. Black, B. A., Copenheaver, C. A., Frank, D. C., Stuckey, M. J., Kormanyos, R. E. Multi-proxy reconstructions of northeastern Pacific sea surface temperature data from trees and Pacific geoduck. Palaeogeography, Palaeoclimatology, Palaeoecology. 278 (1-4), 40-47 (2009).
  28. Suess, H. E. The Radiocarbon Record in Tree Rings of the Last 8000 Years. Radiocarbon. 22 (2), 200-209 (1980).
  29. Reimer, P. J. IntCal04 terrestrial radiocarbon age calibration, 0-26 Cal Kyr BP. Radiocarbon. 46 (3), 1029-1058 (2004).
  30. Muñoz, A. A., et al. Multidecadal environmental pollution in a mega-industrial area in central Chile registered by tree rings. Science of the Total Environment. 696, 133915 (2019).
  31. Briffa, K. R., Melvin, T. M., Hughes, M., Swetnam, T., Diaz, H. A Closer Look at Regional Curve Standardization of Tree-Ring Records: Justification of the Need, a Warning of Some Pitfalls, and Suggested Improvements in Its Application. Dendroclimatology. Developments in Paleoenvironmental Research. 11, (2011).
  32. Cook, E. R., Peters, K. Calculating unbiased tree-ring indices for the study of climatic and environmental change. The Holocene. 7 (3), 361-370 (1997).
  33. Brienen, R. J. W., Gloor, E., Zuidema, P. A. Detecting evidence for CO2 fertilization from tree ring studies: The potential role of sampling biases. Global Biogeochemical Cycles. 26 (1), 1-13 (2012).
  34. Wright, W. E., Baisan, C., Streck, M., Wright, W. W., Szejner, P. Dendrochronology and middle Miocene petrified oak: Modern counterparts and interpretation. Palaeogeography, Palaeoclimatology, Palaeoecology. 445, 38-49 (2016).
  35. Stahle, D. W., et al. The Mexican Drought Atlas: Tree-ring reconstructions of the soil moisture balance during the late pre-Hispanic, colonial, and modern eras. Quaternary Science Reviews. 149, 34-60 (2016).
  36. Cook, E. R., et al. Old World megadroughts and pluvials during the Common Era. Science Advances. 1 (10), 1500561 (2015).
  37. Morales, M. S., et al. Six hundred years of South American tree rings reveal an increase in severe hydroclimatic events since mid-20th century. Proceedings of the National Academy of Sciences of the United States of America. 117 (29), 16816-16823 (2020).
  38. Wilson, R., et al. Last millennium northern hemisphere summer temperatures from tree rings: Part I: The long term context. Quaternary Science Reviews. 134, 1-18 (2016).
  39. Anchukaitis, K. J., et al. Last millennium Northern Hemisphere summer temperatures from tree rings: Part II, spatially resolved reconstructions. Quaternary Science Reviews. 163, 1-22 (2017).
  40. Villanueva-Diaz, J., et al. Hydroclimatic variability of the upper Nazas basin: Water management implications for the irrigated area of the Comarca Lagunera, Mexico. Dendrochronologia. 22 (3), 215-223 (2005).
  41. Sauchyn, D. J., St-Jacques, J. M., Luckman, B. H. Long-term reliability of the Athabasca River (Alberta, Canada) as the water source for oil sands mining. Proceedings of the National Academy of Sciences of the United States of America. 112 (41), 12621-12626 (2015).
  42. Woodhouse, C. A., Pederson, G. T., Morino, K., McAfee, S. A., McCabe, G. J. Increasing influence of air temperature on upper Colorado River streamflow. Geophysical Research Letters. 43 (5), 2174-2181 (2016).
  43. Muñoz, A. A., et al. Streamflow variability in the Chilean Temperate-Mediterranean climate transition (35°S-42°S) during the last 400 years inferred from tree-ring records. Climate Dynamics. 47, 4051-4066 (2016).
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Cerano-Paredes, J., Szejner, P., Gutiérrez-García, G., Cervantes-Martínez, R., Cambrón-Sandoval, V. H., Villanueva-Díaz, J., Estrada-Arellano, J. R., Franco-Ramos, O., Vázquez-Selem, L., Castruita-Esparza, L. U. How to Extract Climate Variability from Tree-Rings. J. Vis. Exp. (181), e63414, doi:10.3791/63414 (2022).

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