Special Issue "Impacts of Climate Change on Tree Physiology and Responses of Forest Ecosystems"

A special issue of Forests (ISSN 1999-4907). This special issue belongs to the section "Forest Ecophysiology and Biology".

Deadline for manuscript submissions: closed (15 April 2021).

Special Issue Editor

Dr. Mariangela Fotelli
E-Mail Website
Guest Editor
Hellenic Agricultural Organization-Demeter, Forest Research Institute, Vasilika 570 06, Thessaloniki, Greece
Interests: forest ecophysiology; tree physiology; climate change adaptation and mitigation; carbon and nitrogen balance; water fluxes

Special Issue Information

Dear Colleagues,

Climate change-induced extreme events, such as heat waves, prolonged droughts, and floodings, are increasingly evident. The intensity, frequency, and spatial distribution of such adverse climate phenomena are noticeable. However, forest trees may develop remarkable physiological mechanisms to cope with constantly changing and challenging environmental regimes caused by global warming, rising atmospheric carbon dioxide, largely fluctuating water availability, elevated nitrogen depositions, and others. Whether physiological resilience and resistance on the tree level result in ecophysiological responses that ensure plasticity of forest ecosystems to the concurrent climate change or if, on the contrary, forests may be severely damaged by climate change are core questions of contemporary forest research.

This Special Issue of Forests aims at exploring the state of knowledge and progress on key aspects of tree physiology and forest ecophysiology in light of climate change. We welcome original research papers from the leaf to the ecosystem level, based on experimental, theoretical, or modeling approaches, as well as review articles.

Dr. Mariangela Fotelli
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Forests is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1800 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Climate change
  • Forest ecophysiology
  • Tree physiology
  • Physiological acclimation
  • Water relations and fluxes
  • Nutrient metabolism
  • Nitrogen and carbon balance
  • Secondary metabolites

Published Papers (8 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Jump to: Review

Open AccessArticle
Climate Change Effects in a Mediterranean Forest Following 21 Consecutive Years of Experimental Drought
Forests 2021, 12(3), 306; https://doi.org/10.3390/f12030306 - 06 Mar 2021
Viewed by 493
Abstract
Research Highlights: A small, long-term decrease in the water availability in a Mediterranean holm oak forest elicited strong effects on tree stem growth, mortality, and species composition, which led to changes in the ecosystem function and service provision. Background and Objectives: Many forest [...] Read more.
Research Highlights: A small, long-term decrease in the water availability in a Mediterranean holm oak forest elicited strong effects on tree stem growth, mortality, and species composition, which led to changes in the ecosystem function and service provision. Background and Objectives: Many forest ecosystems are increasingly challenged by stress conditions under climate change. These new environmental constraints may drive changes in species distribution and ecosystem function. Materials and Methods: An evergreen Mediterranean holm oak (Quercus ilex L.) forest was subjected to 21 consecutive years of experimental drought (performing 30% of rainfall exclusion resulted in a 15% decrease in soil moisture). The effects of the annual climatic conditions and the experimental drought on a tree and shrub basal area increment were studied, with a focus on the two most dominant species (Q. ilex and the tall shrub Phillyrea latifolia L.). Results: Stem growth decreased and tree mortality increased under the experimental drought conditions and in hot and dry years. These effects differed between the two dominant species: the basal area of Q. ilex (the current, supradominant species) was dependent on water availability and climatic conditions, whereas P. latifolia was more tolerant to drought and experienced increased growth rates in plots where Q. ilex decay rates were high. Conclusions: Our findings reveal that small changes in water availability drive changes in species growth, composition, and distribution, as demonstrated by the continuous and ongoing replacement of the current supradominant Q. ilex by the subdominant P. latifolia, which is better adapted to tolerate hot and dry environments. The consequences of these ecological transformations for ecosystem function and service provision to human society are discussed. Full article
Show Figures

Figure 1

Open AccessArticle
Sap Flow in Aleppo Pine in Greece in Relation to Sapwood Radial Gradient, Temporal and Climatic Variability
Forests 2021, 12(1), 2; https://doi.org/10.3390/f12010002 - 22 Dec 2020
Viewed by 361
Abstract
Research Highlights: The radial gradient of sap flux density (Js) and the effects of climatic factors on sap flow of Aleppo pine were assessed at different time scales in an eastern Mediterranean ecosystem to improve our understanding of the species water balance. Background [...] Read more.
Research Highlights: The radial gradient of sap flux density (Js) and the effects of climatic factors on sap flow of Aleppo pine were assessed at different time scales in an eastern Mediterranean ecosystem to improve our understanding of the species water balance. Background and Objectives: Aleppo pine’s sap flow radial profile and responses to environmental parameters in the eastern Mediterranean were, to our best knowledge, originating to date from more arid planted forests. Information from natural forests in this region was lacking. Our objectives were to (a) determine the species’ radial variability in Js on a diurnal and seasonal basis and under different climatic conditions, (b) scale up to tree sap flow taking into account the radial profile of Js and (c) determine the responses of Aleppo pine’s sap flow over the year to climatic variability. Materials and Methods: Js was monitored in Aleppo pine in a natural forest in northern Greece with Granier’s method using sensors at three sapwood depths (21, 51, and 81 mm) during two periods differing in climatic conditions, particularly in soil water availability. Results: Js was the highest at 21 mm sapwood depth, and it declined with increasing depth. A steeper gradient of Js in deep sapwood was observed under drier conditions. The same patterns of radial variability in Js were maintained throughout the year, but the contribution of inner sapwood to sap flow was the highest in autumn when the lower seasonal Js was recorded in both study periods. Not taking into account the radial gradient of Js in the studied Aleppo pine would result in a c. 20.2–27.7 % overestimation of total sap flow on a sapwood basis (Qs), irrespective of climatic conditions. On a diurnal and seasonal basis, VPD was the strongest determinant of sap flux density, while at a larger temporal scale, the effect of soil water content was evident. At SWC > 20% sap flow responded positively to increasing solar radiation and VPD, indicating the decisive role of water availability in the studied region. Moreover, in drier days with VPD > 0.7 KPa, SWC controlled the variation of sap flow. Conclusions: There is a considerable radial variability in Js of the studied Aleppo pine and a considerable fluctuation of sap flow with environmental dynamics that should be taken into account when addressing the species water balance. Full article
Show Figures

Figure 1

Open AccessArticle
Stomatal and Leaf Morphology Response of European Beech (Fagus sylvatica L.) Provenances Transferred to Contrasting Climatic Conditions
Forests 2020, 11(12), 1359; https://doi.org/10.3390/f11121359 - 18 Dec 2020
Cited by 1 | Viewed by 533
Abstract
Climate change-induced elevated temperatures and drought are considered to be serious threats to forest ecosystems worldwide, negatively affecting tree growth and viability. We studied nine European beech (Fagus sylvatica L.) provenances located in two provenance trial plots with contrasting climates in Central [...] Read more.
Climate change-induced elevated temperatures and drought are considered to be serious threats to forest ecosystems worldwide, negatively affecting tree growth and viability. We studied nine European beech (Fagus sylvatica L.) provenances located in two provenance trial plots with contrasting climates in Central Europe. Stomata play a vital role in the water balance of plants by regulating gaseous exchanges between plants and the atmosphere. Therefore, to explain the possible adaptation and acclimation of provenances to climate conditions, stomatal (stomatal density, the length of guard cells, and the potential conductance index) and leaf morphological traits (leaf size, leaf dry weight and specific leaf area) were assessed. The phenotypic plasticity index was calculated from the variability of provenances’ stomatal and leaf traits between the provenance plots. We assessed the impact of various climatic characteristics and derived indices (e.g., ecodistance) on intraspecific differences in stomatal and leaf traits. Provenances transferred to drier and warmer conditions acclimated through a decrease in stomatal density, the length of guard cells, potential conductance index, leaf size and leaf dry weight. The reduction in stomatal density and the potential conductance index was proportional to the degree of aridity difference between the climate of origin and conditions of the new site. Moreover, we found that the climate heterogeneity and latitude of the original provenance sites influence the phenotypic plasticity of provenances. Provenances from lower latitudes and less heterogeneous climates showed higher values of phenotypic plasticity. Furthermore, we observed a positive correlation between phenotypic plasticity and mortality in the arid plot but not in the more humid plot. Based on these impacts of the climate on stomatal and leaf traits of transferred provenances, we can improve the predictions of provenance reactions for future scenarios of global climate change. Full article
Show Figures

Figure 1

Open AccessArticle
Tree Line Shift in the Olympus Mountain (Greece) and Climate Change
Forests 2020, 11(9), 985; https://doi.org/10.3390/f11090985 - 14 Sep 2020
Viewed by 663
Abstract
One of the effects of climate change is, among others, changes to forest ecosystems. Research Highlights: Temperature increases and upward tree line shifts are linked in many studies. However, the impact of climate change on tree lines has not been studied in Greece. [...] Read more.
One of the effects of climate change is, among others, changes to forest ecosystems. Research Highlights: Temperature increases and upward tree line shifts are linked in many studies. However, the impact of climate change on tree lines has not been studied in Greece. Background and Objectives: The aim of this study is to assess the relation of tree line shifts and climate change in Olympus mountain, and especially in a protected area. Materials and Methods: In the Olympus mountain, which includes a protected area (the Olympus National Park core) since 1938, GIS data regarding forest cover were analyzed, while climate change from a previous study is presented. Results: Forest expansion and an upward tree line shift are proven in the Olympus mountain area. In the National Park core, the tree line shift is the result of climate change and attributed to the significant temperature increase in the growing season. Conclusions: There are strong indications that a temperature increase leads to an upward shift of the tree lines in the National Park core. Full article
Show Figures

Figure 1

Open AccessArticle
High Nitrate or Ammonium Applications Alleviated Photosynthetic Decline of Phoebe bournei Seedlings under Elevated Carbon Dioxide
Forests 2020, 11(3), 293; https://doi.org/10.3390/f11030293 - 06 Mar 2020
Cited by 1 | Viewed by 665
Abstract
Phoebe bournei is a precioustimber species and is listed as a national secondary protection plant in China. However, seedlings show obvious photosynthetic declinewhen grown long-term under an elevated CO2 concentration (eCO2). The global CO2 concentration is predicted to reach [...] Read more.
Phoebe bournei is a precioustimber species and is listed as a national secondary protection plant in China. However, seedlings show obvious photosynthetic declinewhen grown long-term under an elevated CO2 concentration (eCO2). The global CO2 concentration is predicted to reach 700 μmol·mol−1 by the end of this century; however, little is known about what causes the photosynthetic decline of P. bournei seedlings under eCO2 or whether this photosynthetic decline could be controlled by fertilization measures. To explore this problem, one-year-old P. bournei seedlings were grown in an open-top air chamber under either an ambient CO2 (aCO2) concentration (350 ± 70 μmol·mol−1) or an eCO2 concentration (700 ± 10 μmol·mol−1) from June 12th to September 8th and cultivated in soil treated with either moderate (0.8 g per seedling) or high applications (1.2 g per seedling) of nitrate or ammonium. Under eCO2, the net photosynthetic rate (Pn) of P. bournei seedlings treated with a moderate nitrate application was 27.0% lower than that of seedlings grown under an aCO2 concentration (p < 0.05), and photosynthetic declineappeared to be accompanied by a reduction of the electron transport rate (ETR), actual photochemical efficiency, chlorophyll content, ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco), rubisco activase (RCA) content, leaf thickness, and stomatal density. The Pn of seedlings treated with a high application of nitrate under eCO2 was 5.0% lower than that of seedlings grown under aCO2 (p > 0.05), and photosynthetic declineoccurred more slowly, accompanied by a significant increase in rubisco content, RCA content, and stomatal density. The Pn of P. bournei seedlings treated with either a moderate or a high application of ammonium and grown under eCO2 was not significantly differentto that of seedlings grown under aCO2—there was no photosynthetic decline—and the ETR, chlorophyll content, rubisco content, RCA content, and leaf thickness values were all increased. Increasing the application of nitrate or the supply of ammonium could slow down or prevent the photosynthetic declineof P. bournei seedlings under eCO2 by changing the leaf structure and photosynthetic physiological characteristics. Full article
Show Figures

Figure 1

Open AccessArticle
Shifts in Climate–Growth Relationships of Sky Island Pines
Forests 2019, 10(11), 1011; https://doi.org/10.3390/f10111011 - 12 Nov 2019
Cited by 1 | Viewed by 704
Abstract
Rising temperatures and changes in precipitation may affect plant responses, and mountainous regions in particular are sensitive to the impacts of climate change. The Santa Catalina Mountains, near Tucson, Arizona, USA, are among the best known Madrean Sky Islands, which are defined by [...] Read more.
Rising temperatures and changes in precipitation may affect plant responses, and mountainous regions in particular are sensitive to the impacts of climate change. The Santa Catalina Mountains, near Tucson, Arizona, USA, are among the best known Madrean Sky Islands, which are defined by pine-oak forests. We compared the sensitivity and temporal stability of climate–growth relationships to quantify the growth responses of sympatric taxa of ponderosa pine to changing climate. Three taxa (three-needle, mixed-needle, and five-needle types) collected from southern slopes of two contact zones (Mt. Lemmon, Mt. Bigelow) were evaluated. Positive climate–growth correlations in these semiarid high-elevation pine forests indicated a seasonal shift from summer- to spring-dominant precipitation since 1950, which is a critical time for reproduction. Mixed- and five-needle types responded to winter precipitation, and growth was reduced for the five-needle type when spring conditions were dry. Growth trends in response to temperature and specific to site were observed, which indicated the climate signal can be weakened when data are combined into a single chronology. Significant fluctuations in temperature–growth correlations since 1950 occurred for all needle types. These results demonstrated a dramatic shift in sensitivity of annual tree growth to the seasonality of the limiting factor, and a climatic trend that increases local moisture stress may impact the stability of climate–growth relationships. Moreover, output from temperature–growth analyses based on ring-width data (for example from semiarid sites) that does not account for positive and negative growth trends may be adversely affected, potentially impacting climate reconstructions. Full article
Show Figures

Figure 1

Open AccessArticle
Thermal Time and Cardinal Temperatures for Germination of Cedrela odorata L.
Forests 2019, 10(10), 841; https://doi.org/10.3390/f10100841 - 26 Sep 2019
Cited by 2 | Viewed by 907
Abstract
Thermal time models are useful to determine the thermal and temporal requirements for seed germination. This information may be used as a criterion for species distribution in projected scenarios of climate change, especially in threatened species like red cedar. The objectives of this [...] Read more.
Thermal time models are useful to determine the thermal and temporal requirements for seed germination. This information may be used as a criterion for species distribution in projected scenarios of climate change, especially in threatened species like red cedar. The objectives of this work were to determine the cardinal temperatures and thermal time for seeds of Cedrela odorata and to predict the effect of increasing temperature in two scenarios of climate change. Seeds were placed in germination chambers at constant temperatures ranging from 5 ± 2 to 45 ± 2 °C. Germination rate was analyzed in order to calculate cardinal temperatures and thermal time. The time required for germination of 50% of population was estimated for the current climate, as well as under the A2 and B2 scenarios for the year 2050. The results showed that base, optimal and maximal temperatures were −0.5 ± 0.09, 38 ± 1.6 and 53.3 ± 2.1 °C, respectively. Thermal time (θ1(50)) was 132.74 ± 2.60 °Cd, which in the current climate scenario accumulates after 5.5 days. Under the A2 scenario using the English model, this time is shortened to 4.5 days, while under scenario B2, the time is only 10 hours shorter than the current scenario. Under the German model, the accumulation of thermal time occurs 10 and 6.5 hours sooner than in the current climate under the A2 and B2 models, respectively. The seeds showed a wide range of temperatures for germination, and according to the climate change scenarios, the thermal time accumulates over a shorter period, accelerating the germination of seeds in the understory. This is the first report of a threshold model for C. odorata, one of the most important forest species in tropical environments. Full article
Show Figures

Figure 1

Review

Jump to: Research

Open AccessReview
Adaptation of Forest Trees to Rapidly Changing Climate
Forests 2020, 11(2), 123; https://doi.org/10.3390/f11020123 - 21 Jan 2020
Cited by 4 | Viewed by 2119
Abstract
Climate change leads to global drought-induced stress and increased plant mortality. Tree species living in rapidly changing climate conditions are exposed to danger and must adapt to new climate conditions to survive. Trees respond to changes in the environment in numerous ways. Physiological [...] Read more.
Climate change leads to global drought-induced stress and increased plant mortality. Tree species living in rapidly changing climate conditions are exposed to danger and must adapt to new climate conditions to survive. Trees respond to changes in the environment in numerous ways. Physiological modulation at the seed stage, germination strategy and further development are influenced by many different factors. We review forest abiotic threats (such as drought and heat), including biochemical responses of plants to stress, and biotic threats (pathogens and insects) related to global warming. We then discus the varied adaptations of tree species to changing climate conditions such as seed resistance to environmental stress, improved by an increase in temperature, affinity to specific fungal symbionts, a wide range of tolerance to abiotic environmental conditions in the offspring of populations occurring in continental climate, and germination strategies closely linked to the ecological niche of the species. The existing studies do not clearly indicate whether tree adaptations are shaped by epigenetics or phenology and do not define the role of phenotypic plasticity in tree development. We have created a juxtaposition of literature that is useful in identifying the factors that play key roles in these processes. We compare scientific evidence that species distribution and survival are possible due to phenotypic plasticity and thermal memory with studies that testify that trees’ phenology depends on phylogenesis, but this issue is still open. It is possible that studies in the near future will bring us closer to understanding the mechanisms through which trees adapt to stressful conditions, especially in the context of epigenetic memory in long-lived organisms, and allow us to minimize the harmful effects of climatic events by predicting tree species’ responses or by developing solutions such as assisted migration to mitigate the consequences of these phenomena. Full article
Show Figures

Graphical abstract

Back to TopTop