Contrasted effects of climate change on low-altitude relict Pinus uncinata stands in the Northern French Alps

AbstractThis paper reports on climate-induced growth changes in relict, low-altitude mountain pines (Pinus uncinata Mill. ex. Mirb.) from two refugia with cold microclimates located in the Northern French Alps. The P. uncinata stands analyzed grow at the lower bound of their ecological limit and are thus thought to be sensitive indicators of ongoing climate change. Using dendroecological approaches, we compare tree-ring growth at two closely spaced low-altitude stands in the Chartreuse massif (French Alps): La Plagne and Cirque de Bresson. La Plagne is a N-NW-exposed, ventilated slope with cold air circulating in the scree during summer, and the presence of sporadic permafrost as well as ground overcooling, whereas Cirque de Bresson is located on a small, S-exposed fan with sporadic avalanche activity. At both sites, growth responses of P. uncinata to changes in twentieth and twenty-first centuries temperature and precipitation conditions were investigated by means of moving correlation analyses. At Cirque de Bresson, a significant and rapid decline in tree-ring widths has been observed since the early 1990s. We attribute this decline to (i) increasing air temperatures at the beginning of the growing season (May–June) as well as to (ii) a decrease in soil water potential. At La Plagne, we do not detect any significant trend between the higher summer temperatures and tree growth, presumably as a result of the circulation of cold air in the scree slope, which is thought to maintain fresh and humid soil conditions and therefore favor tree growth. These forest stands provide prime examples on how dendroecology can contribute to the study of the dynamics and local variability of tree growth and climate change in relict forest populations with high ecological and conservation values.

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Directional Variability in Response of Pinus koraiensis Radial Growth to Climate Change

Forests ◽

10.3390/f12121684 ◽

2021 ◽

Vol 12 (12) ◽

pp. 1684

Author(s):

Yingjie Sun ◽

Mark Henderson ◽

Binhui Liu ◽

Hong Yan

Keyword(s):

Climate Change ◽

Tree Ring ◽

Tree Growth ◽

Radial Growth ◽

Maximum Temperature ◽

Pinus Koraiensis ◽

Climate Trends ◽

The Difference ◽

Individual Scale ◽

Individual Trees

Climate change affects forest ecosystems at a variety of scales, from the composition of landscapes to the growth of individual trees. Research across regions and tree species has produced contradictory findings on the effects of climate variables on radial growth. Here, we examine tree ring samples taken from four directions of a tree to determine whether there is directional variability in tree growth in relation to climate trends. The results showed directional differences in the temporal growth processes of Pinus koraiensis, with more commonalities between the west and north directions and between the east and south directions. The contemporaneous June maximum temperature was the main climate factor associated with the difference between the growth of tree rings toward the east or west. Annual tree ring growth toward the east was more affected by the year’s temperature while growth toward the south was more sensitive to the year’s precipitation. Our research demonstrates that diverse response of tree growth to climate may exist at intra-individual scale. This contributes to understanding the sensitivity of tree growth to climate change at differ scales.

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Intra-Annual Wood Formation of Cryptomeria fortunei and Cunninghamia lanceolata in Humid Subtropical China

Frontiers in Ecology and Evolution ◽

10.3389/fevo.2021.733974 ◽

2021 ◽

Vol 9 ◽

Author(s):

Zhuangpeng Zheng ◽

Feifei Zhou ◽

Patrick Fonti ◽

Ping Ren ◽

Xiaoxia Li ◽

...

Keyword(s):

Climate Change ◽

Tree Growth ◽

Boreal Forests ◽

Cambial Activity ◽

Cunninghamia Lanceolata ◽

Growth Monitoring ◽

Specific Information ◽

Summer Drought ◽

Growth Responses ◽

Xylem Growth

Monitoring cambial activity is important for a better understanding of the mechanisms governing xylem growth responses to climate change, providing a scientific basis for tree-ring-based climate reconstructions and projections about tree growth under future climate scenarios. It plays an even more important role in investigating evergreen tree growth in regions with less distinct seasonal cycles. Subtropical evergreen forests have been studied in recent years for their sensitivity to climate change, but it remains unclear how xylem growth is driven by subtropical climates. To further understand the climate-growth response strategies of subtropical conifers, we micro-cored Cryptomeria fortunei and Cunninghamia lanceolata weekly in 2016 and 2017 at the humid subtropical Gushan Mountain in southeastern China. Our weekly growth monitoring showed that the vegetation periods of these two species were both approximately 2–3 months longer than trees in temperate and boreal forests. The growth of C. fortunei in 2016 and 2017 and C. lanceolata in 2017 showed a bimodal pattern of xylogenesis, which was induced by summer drought. The results also indicated that the earlier end of the xylem formation was related to the yearly drought stress. These findings provide more specific information about tree growth and evidence of how climate influences wood production at the cellular level in subtropical regions.

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Competition alters tree growth responses to climate at individual and stand scales

Canadian Journal of Forest Research ◽

10.1139/cjfr-2016-0188 ◽

2017 ◽

Vol 47 (1) ◽

pp. 53-62 ◽

Cited By ~ 31

Author(s):

Kevin R. Ford ◽

Ian K. Breckheimer ◽

Jerry F. Franklin ◽

James A. Freund ◽

Steve J. Kroiss ◽

...

Keyword(s):

Climate Change ◽

Tree Growth ◽

Climate Change Impacts ◽

Tsuga Heterophylla ◽

Individual Growth ◽

Thuja Plicata ◽

Growth Responses ◽

Scale Growth ◽

Important Variation ◽

Hierarchical Bayesian Methods

Understanding how climate affects tree growth is essential for assessing climate change impacts on forests but can be confounded by effects of competition, which strongly influences tree responses to climate. We characterized the joint influences of tree size, competition, and climate on diameter growth using hierarchical Bayesian methods applied to permanent sample plot data from the montane forests of Mount Rainier National Park, Washington State, USA, which are mostly comprised of Abies amabilis Douglas ex Forbes, Tsuga heterophylla (Raf.) Sarg., Pseudotsuga menziesii (Mirb.) Franco, and Thuja plicata Donn ex D. Don. Individual growth was sensitive to climate under low but not high competition, likely because tree ability to increase growth under more favorable climates (generally greater energy availability) was constrained by competition, with important variation among species. Thus, climate change will likely increase individual growth most in uncrowded stands with lower competition. However, crowded stands have more and (or) larger trees, conferring greater capacity for aggregate absolute growth increases. Due to these contrasting effects, our models predicted that climate change will lead to greater stand-scale growth increases in stands with medium compared with low crowding but similar increases in stands with medium and high crowding. Thus, competition will mediate the impacts of climate change on individual- and stand-scale growth in important but complex ways.

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Divergent Growth Responses to Warming between Stand-Grown and Open-Grown Trees in a Dryland Montane Forest in Northwestern China

Forests ◽

10.3390/f10121133 ◽

2019 ◽

Vol 10 (12) ◽

pp. 1133 ◽

Cited By ~ 1

Author(s):

Lei Zhang ◽

Hao Shi ◽

Pengtao Yu ◽

Yanhui Wang ◽

Shufen Pan ◽

...

Keyword(s):

Climate Change ◽

Tree Growth ◽

Elevation Gradient ◽

Montane Forest ◽

Growth Patterns ◽

Forest Growth ◽

Northwestern China ◽

Growth Responses ◽

Internal Factors ◽

High Elevations

Dryland montane forests conserve water for people living in the fluvial plains. The fate of these forests under climate warming is strongly affected by local environmental factors. The question remains of how internal factors contribute to climate change impacts on forest growth in these regions. Here, we investigated tree ring records for similar-aged stand-grown trees and their neighboring open-grown trees at elevation in a dryland montane forest (Picea crassifolia Kom.) in northwestern China. The growth rate of open-grown trees is much higher than their neighboring stand-grown trees across the entire elevation gradient, and the lower the altitude, the greater the difference. Open-grown trees at different elevations showed similar growth patterns, as tree growth at all sites was accelerated over time. In contrast, growth patterns of stand-grown trees were divergent at different altitudes, as growth at high elevations (3100–3300 m a.s.l.) was accelerated, whereas growth at low elevations (2700–2900 m a.s.l.) became stable after the year 1990. Analysis of growth–climate relationships indicated that warming promoted open-grown tree growth across the entire altitude gradient, and also stand-grown tree growth at high elevations, but negatively affected the growth of stand-grown trees at low elevations. Water scarcity can be exacerbated by competition within forests, inhibiting the warming-induced benefits on tree growth. Moving window correlation analysis suggested the negative effect of warming on tree growth at low elevations was diminished after the late 1990s, as the drought stress was alleviated. Our research shows the divergent growth responses to warming of stand-grown and open-grown trees along elevation. It reveals effects of internal factors in determining tree growth response to warming and holds the potential to aid forest management and ecosystem models in responding to climate change.

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Using Tree Rings to Predict the Response of Tree Growth to Climate Change in the Continental United States during the Twenty-First Century

Earth Interactions ◽

10.1175/2010ei362.1 ◽

2010 ◽

Vol 14 (19) ◽

pp. 1-20 ◽

Cited By ~ 23

Author(s):

A. Park Williams ◽

Joel Michaelsen ◽

Steven W. Leavitt ◽

Christopher J. Still

Keyword(s):

Climate Change ◽

United States ◽

Tree Ring ◽

Tree Growth ◽

Ring Width ◽

First Century ◽

Annual Growth ◽

Climate Variations ◽

Tree Ring Data ◽

Twenty First Century

Abstract In the early 1900s, tree-ring scientists began analyzing the relative widths of annual growth rings preserved in the cross sections of trees to infer past climate variations. Now, many ring-width index (RWI) chronologies, each representing a specific site and species, are archived online within the International Tree-Ring Data Bank (ITRDB). Comparing annual tree-ring-width data from 1097 sites in the continental United States to climate data, the authors quantitatively evaluated how trees at each site have historically responded to interannual climate variations. For each site, they developed a climate-driven statistical growth equation that uses regional climate variables to model RWI values. The authors applied these growth models to predict how tree growth will respond to twenty-first-century climate change, considering four climate projections. Although caution should be taken when extrapolating past relationships with climate into the future, the authors observed several clear and interesting patterns in the growth projections that seem likely if warming continues. Most notably, the models project that productivity of dominant tree species in the southwestern United States will decrease substantially during this century, especially in warmer and drier areas. In the northwest, nonlinear growth relationships with temperature may lead to warming-induced declines in growth for many trees that historically responded positively to warmer temperatures. This work takes advantage of the unmatched temporal length and spatial breath of annual growth data available within the ITRDB and exemplifies the potential of this ever-growing archive of tree-ring data to serve in meta-analyses of large-scale forest ecology.

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What evidence exists on the effects of competition on trees’ responses to climate change? A systematic map protocol

Environmental Evidence ◽

10.1186/s13750-021-00249-5 ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

Juliana G. de S. Magalhães ◽

Mariano M. Amoroso ◽

Bruce C. Larson

Keyword(s):

Climate Change ◽

Tree Growth ◽

Full Text ◽

Species Interactions ◽

Forest Type ◽

Climate Change Impacts ◽

Species Selection ◽

Growth Responses ◽

Systematic Map ◽

Individual Tree

Abstract Background Projections of climate change impacts upon forests are likely inaccurate if based on the premise that only climate controls tree growth. Species interactions control growth, but most research has ignored these effects on how trees respond to climate change. Climate change is inducing natural species selection. However, this selection does not occur at the community level. Species selection starts with competition amongst individual trees. Competition is an individual-to-individual antagonistic interaction that, if severe, can constrain the presence of trees within a particular environment. Thus, climate change impacts individual tree selection within forests. Projecting climate change impacts on forests should account for the effects of climate on tree growth and the effects of competition. The inclusion of competition can increase the predictive power of simulations. Methods We propose a protocol to systematically map the available literature on climate change impacts on forests and produce a comprehensive list of methods applied to measure competition and model the competition effects on tree growth responses to climate change. This systematic map is not limited to any country or continent or specific tree species or forest type. The scope of the search focuses on time (when the evidence was published), location (geographic location of the evidence) and research design (competition indices and modelling methods). We will evaluate articles at three levels: title, abstract and full text. We will conduct a full-text assessment on all articles that pass a screening at the title and abstract stages. We will report the extracted evidence in a narrative synthesis to summarize the evidence’s trends and report knowledge gaps.

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Tree-growth response to climatic variability in two climatically contrasting treeline ecotone areas, central Himalaya, Nepal

Canadian Journal of Forest Research ◽

10.1139/cjfr-2015-0089 ◽

2015 ◽

Vol 45 (11) ◽

pp. 1643-1653 ◽

Cited By ~ 15

Author(s):

Krishna B. Shrestha ◽

Annika Hofgaard ◽

Vigdis Vandvik

Keyword(s):

Climate Change ◽

Tree Growth ◽

Growth Response ◽

Summer Temperature ◽

Seasonal Temperature ◽

Central Himalaya ◽

Growth Responses ◽

Drought Effect ◽

Treeline Ecotone ◽

Positive Growth

Tree growth at the treeline ecotone is known to be sensitive to climate variability and is thus considered to be a worldwide biomonitor of climate change. However, our understanding of within-region variation in growth responses through space and time is limited. A dry south-facing slope dominated by Pinus wallichiana A.B. Jacks. and a wet north-facing slope dominated by Abies spectabilis (D. Don) Spach in Nepal, central Himalaya, were used to analyze the intersite (i.e., dry vs. wet sites) and intrasite (i.e., treeline vs. forest line elevations) tree-growth relationships, as well as response to monthly and seasonal temperature and precipitation at annual and bidecadal time scales. At both study sites and at two elevations within each site, growth can be strongly affected by growing-season and nongrowing-season factors; however, there are inconsistencies in terms of the climate–growth relationship across space and over time. At the dry site, only a weak positive growth response to summer temperature is observed. At both sites, there is a negative growth response to winter precipitation at both high and low elevations, and this response is markedly independent of the summer and winter temperature trends of the respective site. At the wet site, growth at the higher elevation is negatively correlated to the early summer temperature, whereas a positive growth response to spring precipitation is observed at the lower elevation, indicating a possible drought effect. The results illustrate how different climatic drivers may govern tree-growth responses both between sites with contrasting climates within a region and along elevational gradients within the treeline ecotone. This underlines the need for multiscale studies and a focus on multiple climate variables when analyzing treeline ecotone responses to climate change.

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The Response of Erica arborea L. Tree Growth to Climate Variability at the Afro-alpine Tropical Highlands of North Ethiopia

Forests ◽

10.3390/f11030310 ◽

2020 ◽

Vol 11 (3) ◽

pp. 310

Author(s):

Miro Jacob ◽

Maaike De Ridder ◽

Marlies Vandenabeele ◽

Tesfaalem Asfaha ◽

Jan Nyssen ◽

...

Keyword(s):

Climate Change ◽

Climate Variability ◽

Tree Ring ◽

Tree Growth ◽

Minimum Temperature ◽

Density Fluctuations ◽

Ethiopian Highlands ◽

Tropical Highlands ◽

Annual Growth Rings ◽

Erica Arborea

The important ecosystem services of the high altitude tropical afro-alpine Erica arborea L. forests are under increasing environmental and human pressure. The Erica treeline ecotone in the Ethiopian highlands forms a temperature-responsive vegetation boundary that is potentially affected by climate change. The cambium of 10 Erica arborea trees in Lib Amba Mountain and Ferrah Amba Mountain in the North Ethiopian highlands was marked in 2012, and corresponding tree disks were sampled after 498 days. Microphotographs of these cambial marks confirmed the formation of annual growth rings (0.76 ± 0.24 mm) with higher vessel density in earlywood and radially flattened fibers in the last layers of the latewood. In-continuum measurements of vessel size and density on microphotographs indicated the formation of inter-annual density fluctuations (IADFs) related to early rainfall in March-May. The same stem disks and 40 increment cores were used for detailed tree-ring analyses—a tree-ring chronology with 18 trees spanning from 1966 to 2014 could be derived. A significant (p < 0.1) positive correlation with minimum temperature in the growing season (August) and a negative correlation with minimum temperature in the spring season (March) were indicated as the most important climate factors regulating tree growth of Erica trees in the afro-alpine forest. The existence of annual tree rings and the proven potential for chronology building encourages further tree-ring analyses of Erica arborea in the afro-alpine tropical highlands in order to link it with climate variability and climate change.

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Retrospective Analysis of Tree Decline Based on Intrinsic Water-Use Efficiency in Semi-Arid Areas of North China

Atmosphere ◽

10.3390/atmos11060577 ◽

2020 ◽

Vol 11 (6) ◽

pp. 577

Author(s):

Weiwei Lu ◽

Xinxiao Yu ◽

Guodong Jia

Keyword(s):

Climate Change ◽

Tree Ring ◽

Tree Growth ◽

North China ◽

Isotope Composition ◽

Ring Width ◽

Carbon Isotope Composition ◽

Tree Decline ◽

Tree Ring Width

Long-term tree growth is significantly affected by climate change, which have become a global concern. Tree-ring width and isotopic information can show how trees respond to climate change on a long-term scale and reveal some phenomena of tree decline or death. In this study, we used isotopic techniques and investigated annual changes in carbon isotope composition and tree-ring width of Populus simonii Carr. in Zhangbei, as well as trends in tree-ring carbon discrimination (Δ13C) and iWUE in normal, mildly declining and severely declining trees, in order to make a retrospective analysis and further understand the process of tree decline. We found that there were significant differences (p < 0.01 **) in δ13C, Δ13C, ci and iWUE at different decline stages, meaning that the δ13C and iWUE could be new indicators of tree health. The iWUE of all groups increased significantly, while the growth rate of declined P. simonii was much higher than that of normal growth P. simonii. According to the analysis, there may be a threshold of iWUE for healthy trees, which once the threshold value is exceeded, it indicates that trees are resistant to adversity and their growth is under stress. Similarly, the changing trend of BAI supports our conclusion with its changes showed that tree growth became slower and slower as degradation progressed. iWUE inferred from tree-ring stable carbon isotope composition is a strong modulator of adaptation capacity in response to environmental stressors under climate change. Elevated annual temperatures and increased groundwater depth are all contributing to the decline of P. simonii in north China.

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Impacts of more frequent droughts on a relict low-altitude Pinus uncinata stand in the French Alps

Frontiers in Ecology and Evolution ◽

10.3389/fevo.2014.00082 ◽

2015 ◽

Vol 2 ◽

Cited By ~ 2

Author(s):

Christophe Corona ◽

Markus Stoffel ◽

Jean-Louis Edouard ◽

...

Keyword(s):

French Alps ◽

Pinus Uncinata ◽

Low Altitude

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