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Spiecker H, Kahle HP. Climate-driven tree growth and mortality in the Black Forest, Germany-Long-term observations. GLOBAL CHANGE BIOLOGY 2023; 29:5908-5923. [PMID: 37551846 DOI: 10.1111/gcb.16897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Accepted: 07/07/2023] [Indexed: 08/09/2023]
Abstract
Episodic tree mortality can be caused by various reasons. This study describes climate-driven tree mortality and tree growth in the Black Forest mountain range in Germany. It is based on a 68-year consistent data series describing the annual mortality of all trees growing in a forest area of almost 250 thousand ha. The study excludes mortality caused by storm, snow and ice, and fire. The sequence of the remaining mortality, the so-called "desiccated trees," is analyzed and compared with the sequence of the climatic water balance during the growing season and the annual radial growth of Norway spruce in the Black Forest. The annual radial growth series covers 121 years and the climatic water balance series 140 years. These unique time series enable a quantitative assessment of multidecadal drought and heat impacts on growth and mortality of forest trees on a regional spatial scale. Data compiled here suggest that the mortality of desiccated trees in the Black Forest during the last 68 years is driven by the climatic water balance. Decreasing climatic water balance coincided with an increase in tree mortality and growth decline. Consecutive hot and dry summers enhance mortality and growth decline as a consequence of drought legacies lasting several years. The sensitivity of tree growth and mortality to changes in the climatic water balance increases with the decreasing trend of the climatic water balance. The findings identify the climatic water balance as the main driver of mortality and growth variation during the 68-year observation period on a landscape-scale including a variety of different sites. They suggest that bark beetle population dynamics modify mortality rates. They as well provide evidence that the mortality during the last 140 years never was as high as in the most recent years.
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Affiliation(s)
- Heinrich Spiecker
- Faculty of Environment and Natural Resources, Chair of Forest Growth and Dendroecology, University of Freiburg, Freiburg, Germany
| | - Hans-Peter Kahle
- Faculty of Environment and Natural Resources, Chair of Forest Growth and Dendroecology, University of Freiburg, Freiburg, Germany
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2
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Doshi A, Shaw M, Tonea R, Moon S, Minyety R, Doshi A, Laine A, Guo J, Danino T. Engineered bacterial swarm patterns as spatial records of environmental inputs. Nat Chem Biol 2023; 19:878-886. [PMID: 37142806 DOI: 10.1038/s41589-023-01325-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 04/06/2023] [Indexed: 05/06/2023]
Abstract
A diverse array of bacteria species naturally self-organize into durable macroscale patterns on solid surfaces via swarming motility-a highly coordinated and rapid movement of bacteria powered by flagella. Engineering swarming is an untapped opportunity to increase the scale and robustness of coordinated synthetic microbial systems. Here we engineer Proteus mirabilis, which natively forms centimeter-scale bullseye swarm patterns, to 'write' external inputs into visible spatial records. Specifically, we engineer tunable expression of swarming-related genes that modify pattern features, and we develop quantitative approaches to decoding. Next, we develop a dual-input system that modulates two swarming-related genes simultaneously, and we separately show that growing colonies can record dynamic environmental changes. We decode the resulting multicondition patterns with deep classification and segmentation models. Finally, we engineer a strain that records the presence of aqueous copper. This work creates an approach for building macroscale bacterial recorders, expanding the framework for engineering emergent microbial behaviors.
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Affiliation(s)
- Anjali Doshi
- Department of Biomedical Engineering, Columbia University, New York City, NY, USA
| | - Marian Shaw
- Department of Biomedical Engineering, Columbia University, New York City, NY, USA
| | - Ruxandra Tonea
- Department of Biomedical Engineering, Columbia University, New York City, NY, USA
| | - Soonhee Moon
- Department of Biomedical Engineering, Columbia University, New York City, NY, USA
| | - Rosalía Minyety
- Department of Biomedical Engineering, Columbia University, New York City, NY, USA
| | - Anish Doshi
- Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, CA, USA
| | - Andrew Laine
- Department of Biomedical Engineering, Columbia University, New York City, NY, USA
| | - Jia Guo
- Department of Psychiatry, Columbia University, New York City, NY, USA
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University, New York City, NY, USA
| | - Tal Danino
- Department of Biomedical Engineering, Columbia University, New York City, NY, USA.
- Herbert Irving Comprehensive Cancer Center, Columbia University, New York City, NY, USA.
- Data Science Institute, Columbia University, New York City, NY, USA.
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3
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Asbjornsen H, McIntire CD, Vadeboncoeur MA, Jennings KA, Coble AP, Berry ZC. Sensitivity and threshold dynamics of Pinus strobus and Quercus spp. in response to experimental and naturally occurring severe droughts. TREE PHYSIOLOGY 2021; 41:1819-1835. [PMID: 33904579 DOI: 10.1093/treephys/tpab056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 03/30/2021] [Indexed: 06/12/2023]
Abstract
Increased drought frequency and severity are a pervasive global threat, yet the capacity of mesic temperate forests to maintain resilience in response to drought remains poorly understood. We deployed a throughfall removal experiment to simulate a once in a century drought in New Hampshire, USA, which coupled with the region-wide 2016 drought, intensified moisture stress beyond that experienced in the lifetimes of our study trees. To assess the sensitivity and threshold dynamics of two dominant northeastern tree genera (Quercus and Pinus), we monitored sap flux density (Js), leaf water potential and gas exchange, growth and intrinsic water-use efficiency (iWUE) for one pretreatment year (2015) and two treatment years (2016-17). Results showed that Js in pine (Pinus strobus L.) declined abruptly at a soil moisture threshold of 0.15 m3 m-3, whereas oak's (Quercus rubra L. and Quercus velutina Lam.) threshold was 0.11 m3 m-3-a finding consistent with pine's more isohydric strategy. Nevertheless, once oaks' moisture threshold was surpassed, Js declined abruptly, suggesting that while oaks are well adapted to moderate drought, they are highly susceptible to extreme drought. The radial growth reduction in response to the 2016 drought was more than twice as great for pine as for oaks (50 vs 18%, respectively). Despite relatively high precipitation in 2017, the oaks' growth continued to decline (low recovery), whereas pine showed neutral (treatment) or improved (control) growth. The iWUE increased in 2016 for both treatment and control pines, but only in treatment oaks. Notably, pines exhibited a significant linear relationship between iWUE and precipitation across years, whereas the oaks only showed a response during the driest conditions, further underscoring the different sensitivity thresholds for these species. Our results provide new insights into how interactions between temperate forest tree species' contrasting physiologies and soil moisture thresholds influence their responses and resilience to extreme drought.
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Affiliation(s)
- Heidi Asbjornsen
- Department of Natural Resources and the Environment, University of New Hampshire, 56 College Rd, Durham, NH 03824, USA
- Earth Systems Research Center, University of New Hampshire, 8 College Rd, Durham, NH 03824, USA
| | - Cameron D McIntire
- Department of Natural Resources and the Environment, University of New Hampshire, 56 College Rd, Durham, NH 03824, USA
- State and Private Forestry, USDA Forest Service, 271 Mast Road, Durham, NH 03824, USA
| | - Matthew A Vadeboncoeur
- Earth Systems Research Center, University of New Hampshire, 8 College Rd, Durham, NH 03824, USA
| | - Katie A Jennings
- Department of Natural Resources and the Environment, University of New Hampshire, 56 College Rd, Durham, NH 03824, USA
- Earth Systems Research Center, University of New Hampshire, 8 College Rd, Durham, NH 03824, USA
| | - Adam P Coble
- Department of Natural Resources and the Environment, University of New Hampshire, 56 College Rd, Durham, NH 03824, USA
- Private Forests Division, Oregon Department of Forestry, 2600 State St, Salem, OR 97310, USA
| | - Z Carter Berry
- Department of Natural Resources and the Environment, University of New Hampshire, 56 College Rd, Durham, NH 03824, USA
- Schmid College of Science and Technology, Chapman University, Orange, CA 92866, USA
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4
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Wilmking M, van der Maaten-Theunissen M, van der Maaten E, Scharnweber T, Buras A, Biermann C, Gurskaya M, Hallinger M, Lange J, Shetti R, Smiljanic M, Trouillier M. Global assessment of relationships between climate and tree growth. GLOBAL CHANGE BIOLOGY 2020; 26:3212-3220. [PMID: 32124523 DOI: 10.1111/gcb.15057] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 02/20/2020] [Indexed: 06/10/2023]
Abstract
Tree-ring records provide global high-resolution information on tree-species responses to global change, forest carbon and water dynamics, and past climate variability and extremes. The underlying assumption is a stationary (time-stable), quasi-linear relationship between tree growth and environment, which however conflicts with basic ecological and evolutionary theory. Indeed, our global assessment of the relevant tree-ring literature demonstrates non-stationarity in the majority of tested cases, not limited to specific proxies, environmental parameters, regions or species. Non-stationarity likely represents the general nature of the relationship between tree-growth proxies and environment. Studies assuming stationarity however score two times more citations influencing other fields of science and the science-policy interface. To reconcile ecological reality with the application of tree-ring proxies for climate or environmental estimates, we provide a clarification of the stationarity concept, propose a simple confidence framework for the re-evaluation of existing studies and recommend the use of a new statistical tool to detect non-stationarity in tree-ring proxies. Our contribution is meant to stimulate and facilitate discussion in light of our results to help increase confidence in tree-ring-based climate and environmental estimates for science, the public and policymakers.
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Affiliation(s)
- Martin Wilmking
- Institute of Botany and Landscape Ecology, University Greifswald, Greifswald, Germany
| | | | - Ernst van der Maaten
- Institute of Botany and Landscape Ecology, University Greifswald, Greifswald, Germany
| | - Tobias Scharnweber
- Institute of Botany and Landscape Ecology, University Greifswald, Greifswald, Germany
| | - Allan Buras
- Institute of Botany and Landscape Ecology, University Greifswald, Greifswald, Germany
| | - Christine Biermann
- Department of Geography and Environmental Studies, University of Colorado, Colorado Springs, CO, USA
| | - Marina Gurskaya
- Institute of Plant and Animal Ecology, Ural Branch, Russian Academy of Sciences, Ekaterinburg, Russia
| | - Martin Hallinger
- Institute of Botany and Landscape Ecology, University Greifswald, Greifswald, Germany
| | - Jelena Lange
- Institute of Botany and Landscape Ecology, University Greifswald, Greifswald, Germany
| | - Rohan Shetti
- Institute of Botany and Landscape Ecology, University Greifswald, Greifswald, Germany
| | - Marko Smiljanic
- Institute of Botany and Landscape Ecology, University Greifswald, Greifswald, Germany
| | - Mario Trouillier
- Institute of Botany and Landscape Ecology, University Greifswald, Greifswald, Germany
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Buttò V, Shishov V, Tychkov I, Popkova M, He M, Rossi S, Deslauriers A, Morin H. Comparing the Cell Dynamics of Tree-Ring Formation Observed in Microcores and as Predicted by the Vaganov-Shashkin Model. FRONTIERS IN PLANT SCIENCE 2020; 11:1268. [PMID: 32922430 PMCID: PMC7457011 DOI: 10.3389/fpls.2020.01268] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 08/03/2020] [Indexed: 05/17/2023]
Abstract
New insights into the intra-annual dynamics of tree-ring formation can improve our understanding of tree-growth response to environmental conditions at high-resolution time scales. Obtaining this information requires, however, a weekly monitoring of wood formation, sampling that is extremely time-intensive and scarcely feasible over vast areas. Estimating the timing of cambial and xylem differentiation by modeling thus represents an interesting alternative for obtaining this important information by other means. Temporal dynamics of cambial divisions can be extracted from the daily tree-ring growth rate computed by the Vaganov-Shashkin (VS) simulation model, assuming that cell production is tightly linked to tree-ring growth. Nonetheless, these predictions have yet to be compared with direct observations of wood development, i.e., via microcoring, over a long time span. We tested the performance of the VS model by comparing the observed and predicted timing of wood formation in black spruce [Picea mariana (Mill.)]. We obtained microcores over 15 years at 5 sites along a latitudinal gradient in Quebec (Canada). The measured variables included cell size and the timing of cell production and differentiation. We calibrated the VS model using daily temperature and precipitation recorded by weather stations located on each site. The predicted and observed timing of cambial and enlarging cells were highly correlated (R 2 = 0.8); nonetheless, we detected a systematic overestimation in the predicted timing of cambial cells, with predictions delayed by 1-20 days compared with observations. The growth rate of cell diameter was correlated with the predicted growth rate assigned to each cambial cell, confirming that cell diameter developmental dynamics have the potential to be inferred by the tree-ring growth curve of the VS model. Model performances decrease substantially in estimating the end of wood formation. The systematic errors suggest that the actual relationships implemented in the model are unable to explain the phenological events in autumn. The mismatch between the observed and predicted timing of wood formation in black spruce within our study area can be reduced by better adapting the VS model to wet sites, a context for which this model has been rarely used.
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Affiliation(s)
- Valentina Buttò
- Département des Sciences fondamentales, Université du Québec à Chicoutimi, Chicoutimi, QC, Canada
- *Correspondence: Valentina Buttò,
| | - Vladimir Shishov
- Laboratory for Integral Studies of Forest Dynamics of Eurasia, Siberian Federal University, Krasnoyarsk, Russia
- Environmental and Research Center, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Ivan Tychkov
- Laboratory for Integral Studies of Forest Dynamics of Eurasia, Siberian Federal University, Krasnoyarsk, Russia
| | - Margarita Popkova
- Laboratory for Integral Studies of Forest Dynamics of Eurasia, Siberian Federal University, Krasnoyarsk, Russia
| | - Minhui He
- College of Forestry, Northwest Agriculture and Forestry University, Yangling, China
| | - Sergio Rossi
- Département des Sciences fondamentales, Université du Québec à Chicoutimi, Chicoutimi, QC, Canada
- Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems, Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Annie Deslauriers
- Département des Sciences fondamentales, Université du Québec à Chicoutimi, Chicoutimi, QC, Canada
| | - Hubert Morin
- Département des Sciences fondamentales, Université du Québec à Chicoutimi, Chicoutimi, QC, Canada
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Au RAD. Tree Rings of Pinus ponderosa and Juniperus virginiana Show Different Responses to Stand Density and Water Availability in the Nebraska Grasslands. AMERICAN MIDLAND NATURALIST 2018. [DOI: 10.1674/0003-0031-180.1.18] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- R. Aus Der Au
- Department of Geography, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
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Mokria M, Gebrekirstos A, Abiyu A, Van Noordwijk M, Bräuning A. Multi-century tree-ring precipitation record reveals increasing frequency of extreme dry events in the upper Blue Nile River catchment. GLOBAL CHANGE BIOLOGY 2017; 23:5436-5454. [PMID: 28712116 DOI: 10.1111/gcb.13809] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 06/23/2017] [Indexed: 06/07/2023]
Abstract
Climate-related environmental and humanitarian crisis are important challenges in the Great Horn of Africa (GHA). In the absence of long-term past climate records in the region, tree-rings are valuable climate proxies, reflecting past climate variations and complementing climate records prior to the instrumental era. We established annually resolved multi-century tree-ring chronology from Juniperus procera trees in northern Ethiopia, the longest series yet for the GHA. The chronology correlates significantly with wet-season (r = .64, p < .01) and annual (r = .68, p < .01) regional rainfall. Reconstructed rainfall since A.D. 1811 revealed significant interannual variations between 2.2 and 3.8 year periodicity, with significant decadal and multidecadal variations during 1855-1900 and 1960-1990. The duration of negative and positive rainfall anomalies varied between 1-7 years and 1-8 years. Approximately 78.4% (95%) of reconstructed dry (extreme dry) and 85.4% (95%) of wet (extreme wet) events lasted for 1 year only and corresponded to historical records of famine and flooding, suggesting that future climate change studies should be both trend and extreme event focused. The average return periods for dry (extreme dry) and wet (extreme wet) events were 4.1 (8.8) years and 4.1 (9.5) years. Extreme-dry conditions during the 19th century were concurrent with drought episodes in equatorial eastern Africa that occurred at the end of the Little Ice Age. El Niño and La Niña events matched with 38.5% and 50% of extreme-dry and extreme-wet events. Equivalent matches for positive and negative Indian Ocean Dipole events were weaker, reaching 23.1 and 25%, respectively. Spatial correlations revealed that reconstructed rainfall represents wet-season rainfall variations over northern Ethiopia and large parts of the Sahel belt. The data presented are useful for backcasting climate and hydrological models and for developing regional strategic plans to manage scarce and contested water resources. Historical perspectives on long-term regional rainfall variability improve the interpretation of recent climate trends.
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Affiliation(s)
- Mulugeta Mokria
- World Agroforestry Centre (ICRAF), United Nations Avenue, Nairobi, Kenya
- Institute of Geography, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Aster Gebrekirstos
- World Agroforestry Centre (ICRAF), United Nations Avenue, Nairobi, Kenya
| | - Abrham Abiyu
- Amhara Agricultural Research Institute (ARARI), Amhara Region, Ethiopia
| | - Meine Van Noordwijk
- World Agroforestry Centre (ICRAF), United Nations Avenue, Nairobi, Kenya
- Plant Production Systems, Wageningen University, Wageningen, the Netherlands
| | - Achim Bräuning
- Institute of Geography, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
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von Arx G, Arzac A, Fonti P, Frank D, Zweifel R, Rigling A, Galiano L, Gessler A, Olano JM. Responses of sapwood ray parenchyma and non‐structural carbohydrates of
Pinus sylvestris
to drought and long‐term irrigation. Funct Ecol 2017. [DOI: 10.1111/1365-2435.12860] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Georg von Arx
- Swiss Federal Institute for Forest Snow and Landscape Research WSL Zuercherstrasse 111 CH‐8903 Birmensdorf Switzerland
- SwissForestLab Zuercherstrasse 111 CH‐8903 Birmensdorf Switzerland
| | - Alberto Arzac
- School of Ecology and Geography Siberian Federal University 79 Svobodny pr 660041 Krasnoyarsk Russia
- Departamento de Biología Vegetal y Ecología Facultad de Ciencia y Tecnología Universidad del País Vasco Barrio Sarriena s/n E–48940 Leioa Spain
| | - Patrick Fonti
- Swiss Federal Institute for Forest Snow and Landscape Research WSL Zuercherstrasse 111 CH‐8903 Birmensdorf Switzerland
- SwissForestLab Zuercherstrasse 111 CH‐8903 Birmensdorf Switzerland
| | - David Frank
- Swiss Federal Institute for Forest Snow and Landscape Research WSL Zuercherstrasse 111 CH‐8903 Birmensdorf Switzerland
- SwissForestLab Zuercherstrasse 111 CH‐8903 Birmensdorf Switzerland
- Laboratory of Tree‐Ring Research University of Arizona Tucson AZ85721 USA
| | - Roman Zweifel
- Swiss Federal Institute for Forest Snow and Landscape Research WSL Zuercherstrasse 111 CH‐8903 Birmensdorf Switzerland
- SwissForestLab Zuercherstrasse 111 CH‐8903 Birmensdorf Switzerland
| | - Andreas Rigling
- Swiss Federal Institute for Forest Snow and Landscape Research WSL Zuercherstrasse 111 CH‐8903 Birmensdorf Switzerland
- SwissForestLab Zuercherstrasse 111 CH‐8903 Birmensdorf Switzerland
| | - Lucia Galiano
- Swiss Federal Institute for Forest Snow and Landscape Research WSL Zuercherstrasse 111 CH‐8903 Birmensdorf Switzerland
| | - Arthur Gessler
- Swiss Federal Institute for Forest Snow and Landscape Research WSL Zuercherstrasse 111 CH‐8903 Birmensdorf Switzerland
- SwissForestLab Zuercherstrasse 111 CH‐8903 Birmensdorf Switzerland
| | - José Miguel Olano
- Departamento de Ciencias Agroforestales EU de Ingenierías Agrarias iuFOR‐Universidad de Valladolid Campus Duques de Soria 42004 Soria Spain
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von Arx G, Arzac A, Olano JM, Fonti P. Assessing Conifer Ray Parenchyma for Ecological Studies: Pitfalls and Guidelines. FRONTIERS IN PLANT SCIENCE 2015; 6:1016. [PMID: 26635842 PMCID: PMC4649045 DOI: 10.3389/fpls.2015.01016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Accepted: 11/03/2015] [Indexed: 05/09/2023]
Abstract
Ray parenchyma is an essential tissue for tree functioning and survival. This living tissue plays a major role for storage and transport of water, nutrients, and non-structural carbohydrates (NSC), thus regulating xylem hydraulics and growth. However, despite the importance of rays for tree carbon and water relations, methodological challenges hamper knowledge about ray intra- and inter-tree variability and its ecological meaning. In this study we provide a methodological toolbox for soundly quantifying spatial and temporal variability of different ray features. Anatomical ray features were surveyed in different cutting planes (cross-sectional, tangential, and radial) using quantitative image analysis on stem-wood micro-sections sampled from 41 mature Scots pines (Pinus sylvestris). The percentage of ray surface (PERPAR), a proxy for ray volume, was compared among cutting planes and between early- and latewood to assess measurement-induced variability. Different tangential ray metrics were correlated to assess their similarities. The accuracy of cross-sectional and tangential measurements for PERPAR estimates as a function of number of samples and the measured wood surface was assessed using bootstrapping statistical technique. Tangential sections offered the best 3D insight of ray integration into the xylem and provided the most accurate estimates of PERPAR, with 10 samples of 4 mm(2) showing an estimate within ±6.0% of the true mean PERPAR (relative 95% confidence interval, CI95), and 20 samples of 4 mm(2) showing a CI95 of ±4.3%. Cross-sections were most efficient for establishment of time series, and facilitated comparisons with other widely used xylem anatomical features. Earlywood had significantly lower PERPAR (5.77 vs. 6.18%) and marginally fewer initiating rays than latewood. In comparison to tangential sections, PERPAR was systematically overestimated (6.50 vs. 4.92%) and required approximately twice the sample area for similar accuracy. Radial cuttings provided the least accurate PERPAR estimates. This evaluation of ray parenchyma in conifers and the presented guidelines regarding data accuracy as a function of measured wood surface and number of samples represent an important methodological reference for ray quantification, which will ultimately improve the understanding of the fundamental role of ray parenchyma tissue for the performance and survival of trees growing in stressed environments.
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Affiliation(s)
- Georg von Arx
- Landscape Dynamics Research Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorf, Switzerland
| | - Alberto Arzac
- Departamento de Biología Vegetal y Ecología, Facultad de Ciencia y Tecnología, Universidad del País VascoLeioa, Spain
| | - José M. Olano
- Departamento de Ciencias Agroforestales, Escuela Universitaria de Ingenierías Agrarias, Instituto Universitario de Investigación en Gestión Forestal Sostenible-Universidad de ValladolidSoria, Spain
| | - Patrick Fonti
- Landscape Dynamics Research Unit, Swiss Federal Institute for Forest, Snow and Landscape Research WSLBirmensdorf, Switzerland
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Filling the Eastern European gap in millennium-long temperature reconstructions. Proc Natl Acad Sci U S A 2013; 110:1773-8. [PMID: 23319641 DOI: 10.1073/pnas.1211485110] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Tree ring-based temperature reconstructions form the scientific backbone of the current global change debate. Although some European records extend into medieval times, high-resolution, long-term, regional-scale paleoclimatic evidence is missing for the eastern part of the continent. Here we compile 545 samples of living trees and historical timbers from the greater Tatra region to reconstruct interannual to centennial-long variations in Eastern European May-June temperature back to 1040 AD. Recent anthropogenic warming exceeds the range of past natural climate variability. Increased plague outbreaks and political conflicts, as well as decreased settlement activities, coincided with temperature depressions. The Black Death in the mid-14th century, the Thirty Years War in the early 17th century, and the French Invasion of Russia in the early 19th century all occurred during the coldest episodes of the last millennium. A comparison with summer temperature reconstructions from Scandinavia, the Alps, and the Pyrenees emphasizes the seasonal and spatial specificity of our results, questioning those large-scale reconstructions that simply average individual sites.
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