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

Deadline for manuscript submissions: closed (10 October 2021) | Viewed by 29054

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Dr. Ovidiu Badea

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Guest Editor

1. Biometrics and Forest monitoring, National Institute for Research and Development in Forestry “Marin Dracea”, Voluntari, Romania
2. Romanian Academy, Bucharest, Romania
Interests: forestry and environmental research; forest ecology; forest resources and monitoring; forest conservation and biodiversity; LUCC in the forestry sector and impacts on carbon cycling and greenhouse gas emissions; GIS and remote sensing for sustainable forest monitoring and management
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Dr. Alessandra De Marco

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Co-Guest Editor

Department of Sustainability, Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), Via Anguillarese 301, 00123 Rome, Italy
Interests: atmospheric pollution; impacts on ecosystems
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Dr. Pierre Sicard

E-Mail Website1 Website2
Co-Guest Editor

ARGANS 260 route du Pin Montard, 06904 Sophia-Antipolis, CEDEX, France
Interests: ground-level ozone; epidemiological study; impacts on forests
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Dr. Mihai A. Tanase

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Co-Guest Editor

Department of Geology, Geography and Environment, University of Alcalá, Alcala de Henares, Spain
Interests: forest management; vegetation; remote sensing; mapping; spatial analysis; satellite image processing; satellite image analysis; geomatics; geospatial science; environment
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Special Issue Information

Dear Colleagues,

As Guest Editor of the journal Forests (EISSN 1999-4907), IF: 2.221), I would like to invite you to submit an original research paper or a review article to this Special Issue, “Climate Change and Air Pollution Effects on Forest Ecosystems”.

Both climate change and air pollution have large negative impacts on physiological processes and functions at the individual tree level and on whole forest ecosystems. The objective of climate change and air quality monitoring is to make decisions, based on scientific knowledge, on how to best manage and improve the current state of the environment. Our ability to take urgent measures to combat climate change and its impact on forest ecosystems and conserve forest biodiversity depends upon knowing the latest scientific results on the status of forest ecosystems. At present, climate and air quality monitoring in forests around the globe is performed in different networks by different organizations. Unfortunately, there are a lot of gaps in our knowledge of the detection and monitoring of their effects on forest ecosystems. There is a need for a better understanding of interactions and fluxes at the ecosystem level and how different pollutants and climate effects are reflected or transferred in quantifiable ecosystem variables in both the short and long term. For the detection and monitoring of air pollution actions in the climate change context to be relevant, there is a need for better science–policy interaction. Use of Earth Observation data for processing, validation, and analysis and new technical developments may provide us with new results in climate change and air pollution investigations.

Dr. Ovidiu Badea
Dr. Alessandra De Marco
Dr. Pierre Sicard
Dr. Mihai A. Tanase
Guest Editors

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 submissions that pass pre-check are 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 2600 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
Air pollution
Forest ecosystems
Monitoring
Detection
Conservation of forest resources
Adaptation

Published Papers (11 papers)

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Editorial

Jump to: Research, Review

3 pages, 627 KiB

Open AccessEditorial

Climate Change and Air Pollution Effect on Forest Ecosystems

by Ovidiu Badea

Forests 2021, 12(12), 1642; https://doi.org/10.3390/f12121642 - 26 Nov 2021

Cited by 1 | Viewed by 2142

Abstract

Climate change, air pollution, urbanization, globalization, demographic changes and changing consumption patterns affect forests and their social, cultural, ecological and economic functions, resulting in consequences for the social value of forests and for people’s livelihoods, health and quality of life [...] Full article

(This article belongs to the Special Issue Climate Change and Air Pollution Effects on Forest Ecosystems)

Research

Jump to: Editorial, Review

18 pages, 4881 KiB

Open AccessArticle

Shifts in Forest Species Composition and Abundance under Climate Change Scenarios in Southern Carpathian Romanian Temperate Forests

by Juan García-Duro, Albert Ciceu, Serban Chivulescu, Ovidiu Badea, Mihai A. Tanase and Cristina Aponte

Forests 2021, 12(11), 1434; https://doi.org/10.3390/f12111434 - 21 Oct 2021

Cited by 16 | Viewed by 2232

Abstract

The structure and functioning of temperate forests are shifting due to changes in climate. Foreseeing the trajectory of such changes is critical to implementing adequate management practices and defining long-term strategies. This study investigated future shifts in temperate forest species composition and abundance expected to occur due to climate change. It also identified the ecological mechanisms underpinning such changes. Using an altitudinal gradient in the Romanian Carpathian temperate forests encompassing several vegetation types, we explored forest change using the Landis-II landscape model coupled with the PnET ecophysiological process model. We specifically assessed the change in biomass, forest production, species composition and natural disturbance impacts under three climate change scenarios, namely, RCP 2.6, 4.5 and 8.5. The results show that, over the short term (15 years), biomass across all forest types in the altitudinal gradient will increase, and species composition will remain unaltered. In contrast, over the medium and long terms (after 2040), changes in species composition will accelerate, with some species spreading (e.g., Abies alba Mill.) and others declining (e.g., Fagus sylvatica L.), particularly under the most extreme climate change scenario. Some forest types (e.g., Picea abies (L.) karst forests) in the Southern Carpathians will notably increase their standing biomass due to climate change, compared to other types, such as Quercus forests. Our findings suggest that climate change will alter the forest composition and species abundance, with some forests being particularly vulnerable to climate change, e.g., F. sylvatica forests. As far as productivity and forest composition changes are concerned, management practices should accommodate the new conditions in order to mitigate climate change impacts. Full article

(This article belongs to the Special Issue Climate Change and Air Pollution Effects on Forest Ecosystems)

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24 pages, 9637 KiB

Open AccessFeature PaperArticle

Applications of TLS and ALS in Evaluating Forest Ecosystem Services: A Southern Carpathians Case Study

by Alexandru Claudiu Dobre, Ionuț-Silviu Pascu, Ștefan Leca, Juan Garcia-Duro, Carmen-Elena Dobrota, Gheorghe Marian Tudoran and Ovidiu Badea

Forests 2021, 12(9), 1269; https://doi.org/10.3390/f12091269 - 17 Sep 2021

Cited by 6 | Viewed by 2758

Abstract

Forests play an important role in biodiversity conservation, being one of the main providers of ecosystem services, according to the Economics of Ecosystems and Biodiversity. The functions and ecosystem services provided by forests are various concerning the natural capital and the socio-economic systems. Past decades of remote-sensing advances make it possible to address a large set of variables, including both biophysical parameters and ecological indicators, that characterize forest ecosystems and their capacity to supply services. This research aims to identify and implement existing methods that can be used for evaluating ecosystem services by employing airborne and terrestrial stationary laser scanning on plots from the Southern Carpathian mountains. Moreover, this paper discusses the adaptation of field-based approaches for evaluating ecological indicators to automated processing techniques based on airborne and terrestrial stationary laser scanning (ALS and TLS). Forest ecosystem functions, such as provisioning, regulation, and support, and the overall forest condition were assessed through the measurement and analysis of stand-based biomass characteristics (e.g., trees’ heights, wood volume), horizontal structure indices (e.g., canopy cover), and recruitment-mortality processes as well as overall health status assessment (e.g., dead trees identification, deadwood volume). The paper, through the implementation of the above-mentioned analyses, facilitates the development of a complex multi-source monitoring approach as a potential solution for assessing ecosystem services provided by the forest, as well as a basis for further monetization approaches. Full article

(This article belongs to the Special Issue Climate Change and Air Pollution Effects on Forest Ecosystems)

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17 pages, 3962 KiB

Open AccessArticle

Past and Future of Temperate Forests State under Climate Change Effects in the Romanian Southern Carpathians

by Serban Chivulescu, Juan García-Duro, Diana Pitar, Ștefan Leca and Ovidiu Badea

Forests 2021, 12(7), 885; https://doi.org/10.3390/f12070885 - 07 Jul 2021

Cited by 6 | Viewed by 2427

Abstract

Research Highlights: Carpathian forests hold high ecological and economic value while generating conservation concerns, with some of these forests being among the few remaining temperate virgin forests in Europe. Carpathian forests partially lost their original integrity due to their management. Climate change has also gradually contributed to forest changes due to its modification of the environmental conditions. Background and Objectives: Understanding trees’ responses to past climates and forms of management is critical in foreseeing the responses of forests to future conditions. This study aims (1) to determine the sensitivity of Carpathian forests to past climates using dendrochronological records and (2) to describe the effects that climate change and management will have on the attributes of Carpathian forests, with a particular focus on the different response of pure and mixed forests. Materials and Methods: To this end, we first analysed the past climate-induced growth change in a dendrochronological reference series generated for virgin forests in the Romanian Curvature Carpathians and then used the obtained information to calibrate spatially explicit forest Landis-II models for the same region. The model was used to project forest change under four climate change scenarios, from mild to extreme. Results: The dendrochronological analysis revealed a climate-driven increase in forest growth over time. Landis-II model simulations also indicate that the amount of aboveground forest biomass will tend to increase with climate change. Conclusions: There are differences in the response of pure and mixed forests. Therefore, suitable forest management is required when forests change with the climate. Full article

(This article belongs to the Special Issue Climate Change and Air Pollution Effects on Forest Ecosystems)

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18 pages, 6638 KiB

Open AccessArticle

SWAT Model Adaptability to a Small Mountainous Forested Watershed in Central Romania

by Nicu Constantin Tudose, Mirabela Marin, Sorin Cheval, Cezar Ungurean, Serban Octavian Davidescu, Oana Nicoleta Tudose, Alin Lucian Mihalache and Adriana Agafia Davidescu

Forests 2021, 12(7), 860; https://doi.org/10.3390/f12070860 - 29 Jun 2021

Cited by 10 | Viewed by 2799

Abstract

This study aims to build and test the adaptability and reliability of the Soil and Water Assessment Tool hydrological model in a small mountain forested watershed. This ungauged watershed covers 184 km² and supplies 90% of blue water for the Brașov metropolitan area, the second largest metropolitan area of Romania. After building a custom database at the forest management compartment level, the SWAT model was run. Further, using the SWAT-CUP software under the SUFI2 algorithm, we identified the most sensitive parameters required in the calibration and validation stage. Moreover, the sensitivity analysis revealed that the surface runoff is mainly influenced by soil, groundwater and vegetation condition parameters. The calibration was carried out for 2001–2010, while the 1996–1999 period was used for model validation. Both procedures have indicated satisfactory performance and a lower uncertainty of model results in replicating river discharge compared with observed discharge. This research demonstrates that the SWAT model can be applied in small ungauged watersheds after an appropriate parameterisation of its databases. Furthermore, this tool is appropriate to support decision-makers in conceiving sustainable watershed management. It also guides prioritising the most suitable measures to increase the river basin resilience and ensure the water demand under climate change. Full article

(This article belongs to the Special Issue Climate Change and Air Pollution Effects on Forest Ecosystems)

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26 pages, 3771 KiB

Open AccessArticle

Diagnostic Assessment and Restoration Plan for Damaged Forest around the Seokpo Zinc Smelter, Central Eastern Korea

by A Reum Kim, Bong Soon Lim, Jaewon Seol, Chi Hong Lim, Young Han You, Wan Sup Lee and Chang Seok Lee

Forests 2021, 12(6), 663; https://doi.org/10.3390/f12060663 - 24 May 2021

Cited by 8 | Viewed by 2398

Abstract

Research Highlights: This study was carried out to diagnose the forest ecosystem damaged by air pollution and to then develop a restoration plan to be used in the future. The restoration plan was prepared by combining the diagnostic assessment for the damaged forest ecosystem and the reference information obtained from the conservation reserve with an intact forest ecosystem. The restoration plan includes the method for the amelioration of the acidified soil and the plant species to be introduced for restoration of the damaged vegetation depending on the degree of damage. Background and Objectives: The forest ecosystem around the Seokpo smelter was so severely damaged that denuded lands without any vegetation appear, and landslides continue. Therefore, restoration actions are urgently required to prevent more land degradation. This study aims to prepare the restoration plan. Materials and Methods: The diagnostic evaluation was carried out through satellite image analysis and field surveys for vegetation damage and soil acidification. The reference information was obtained from the intact natural forest ecosystem. Results: Vegetation damage was severe near the pollution source and showed a reducing trend as it moved away. The more severe the vegetation damage, the more acidic the soil was, and thereby the exchangeable cation content and vegetation damage were significantly correlated. The restoration plan was prepared by proposing a soil amelioration method and the plants to be introduced. The soil amelioration method focuses on ameliorating acidified soil and supplementing insufficient nutrients. The plants to be introduced for restoring the damaged forest ecosystem were prepared by compiling the reference information, the plants tolerant to the polluted environment, and the early successional species. The restoration plan proposed the Pinus densiflora, Quercus mongolica, and Cornuscontroversa–Juglansmandshurica communities as the reference conditions for the ridge, slope, and valley, respectively, by reflecting the topographic condition. Conclusions: The result of a diagnostic assessment showed that ecological restoration is required urgently as vegetation damage and soil acidification are very severe. The restoration plan was prepared by compiling the results of these diagnostic assessments and reference information collected from intact natural forests. The restoration plan was prepared in the two directions of soil amelioration and vegetation restoration. Full article

(This article belongs to the Special Issue Climate Change and Air Pollution Effects on Forest Ecosystems)

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14 pages, 2041 KiB

Open AccessArticle

Photosynthesis Traits of Pioneer Broadleaves Species from Tailing Dumps in Călimani Mountains (Eastern Carpathians)

by Andrei Popa and Ionel Popa

Forests 2021, 12(6), 658; https://doi.org/10.3390/f12060658 - 22 May 2021

Cited by 2 | Viewed by 1608

Abstract

The reforestation and stable ecological restoration of tailings dumps resulting from surface mining activities in the Călimani Mountains represent an ongoing environmental challenge. To assess the suitability of different tree species for restoration efforts, photosynthetic traits were monitored in four broadleaf pioneer species—green alder (Alnus alnobetula (Ehrh.) K. Koch), aspen (Populus tremula L.), silver birch (Betula pendula Roth.), and goat willow (Salix caprea L.)—that naturally colonized the tailings dumps. Green alder and birch had the highest photosynthetic rate, followed by aspen and goat willow. Water use efficiency parameters (WUE and iWUE) were the highest for green alder and the lowest for birch, with intermediary values for aspen and goat willow. Green alder also exhibited the highest carboxylation efficiency, followed by birch. During the growing season, net assimilation and carboxylation efficiency exhibited a maximum in late July and a minimum in late June. The key limitation parameters of the photosynthetic process derived from the FvCB model (V_cmax and J_max) were the highest for green alder and exhibited a maximum in late July, regardless of the species. Based on photosynthetic traits, the green alder—a woody N₂-fixing shrub—is the most well-adapted and photosynthetically efficient species that naturally colonized the tailings dumps in the Călimani Mountains. Full article

(This article belongs to the Special Issue Climate Change and Air Pollution Effects on Forest Ecosystems)

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11 pages, 2497 KiB

Open AccessArticle

Impact of Industrial Pollution on Radial Growth of Conifers in a Former Mining Area in the Eastern Carpathians (Northern Romania)

by Cristian Gheorghe Sidor, Radu Vlad, Ionel Popa, Anca Semeniuc, Ecaterina Apostol and Ovidiu Badea

Forests 2021, 12(5), 640; https://doi.org/10.3390/f12050640 - 19 May 2021

Cited by 12 | Viewed by 2641

Abstract

The research aims to evaluate the impact of local industrial pollution on radial growth in affected Norway spruce (Picea abies (L.) Karst.) and silver fir (Abies alba Mill.) stands in the Tarnița study area in Suceava. For northeastern Romania, the Tarnița mining operation constituted a hotspot of industrial pollution. The primary processing of non-ferrous ores containing heavy metals in the form of complex sulfides was the main cause of pollution in the Tarnița region from 1968 to 1990. Air pollution of Tarnița induced substantial tree growth reduction from 1978 to 1990, causing a decline in tree health and vitality. Growth decline in stands located over 6 km from the pollution source was weaker or absent. Spruce trees were much less affected by the phenomenon of local pollution than fir trees. We analyzed the dynamics of resilience indices and average radial growth indices and found that the period in which the trees suffered the most from local pollution was between 1978 and 1984. Growth recovery of the intensively polluted stand was observed after the 1990s when the environmental condition improved because of a significant reduction in air pollution. Full article

(This article belongs to the Special Issue Climate Change and Air Pollution Effects on Forest Ecosystems)

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15 pages, 1346 KiB

Open AccessArticle

Growth Relationships in Silver Fir Stands at Their Lower-Altitude Limit in Romania

by Gheorghe-Marian Tudoran, Avram Cicșa, Albert Ciceu and Alexandru-Claudiu Dobre

Forests 2021, 12(4), 439; https://doi.org/10.3390/f12040439 - 05 Apr 2021

Cited by 3 | Viewed by 1764

Abstract

This study presents the biometric relationships among various increments that is useful in both scientific and practical terms for the silvicultural of silver fir. The increments recorded in the biometric characteristics of trees are a faithful indicator of the effect of silvicultural work measures and of environmental conditions. Knowing these increments, and the relationships among them, can contribute to adaptations in silvicultural work on these stands with the purpose of reducing risks generated by environmental factors. We carried an inventory based on tree increment cores. The sample size was determined based on both radial increment and height increment variability of the trees. The sample trees were selected in proportion to their basal area on diameter categories. Current annual height increment (CAI_h) was measured on felled trees from mean tree category. For CAI_h we generated models based on the mean tree height. Percentages of the basal area increment and of form-height increment were used to compute the current annual volume increment percentage (PCAI_v). For the mean tree, the CAI_h estimated through the used models had a root-mean-square error (RMSE) of 0.8749 and for the current annual volume increment (CAI_v) the RMSE value was 0.1295. In even-aged stands, the mean current volume increment tree is a hypothetical tree that may have the mean basal area of all the trees and the form-height of the stand. Conclusions: The diameter, height, and volume increments of trees are influenced by structural conditions and natural factors. The structures comprising several generations of fir mixed with beech and other deciduous trees, which have been obtained by the natural regeneration of local provenances, are stable and must become management targets. Stable structures are a condition for the sustainable management of stands. Full article

(This article belongs to the Special Issue Climate Change and Air Pollution Effects on Forest Ecosystems)

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23 pages, 9783 KiB

Open AccessArticle

Intraspecific Growth Response to Drought of Abies alba in the Southeastern Carpathians

by Georgeta Mihai, Alin Madalin Alexandru, Emanuel Stoica and Marius Victor Birsan

Forests 2021, 12(4), 387; https://doi.org/10.3390/f12040387 - 24 Mar 2021

Cited by 22 | Viewed by 2515

Abstract

The intensity and frequency of drought have increased considerably during the last decades in southeastern Europe, and projected scenarios suggest that southern and central Europe will be affected by more drought events by the end of the 21st century. In this context, assessing the intraspecific genetic variation of forest tree species and identifying populations expected to be best adapted to future climate conditions is essential for increasing forest productivity and adaptability. Using a tree-ring database from 60 populations of 38-year-old silver fir (Abies alba) in five trial sites established across Romania, we studied the variation of growth and wood characteristics, provenance-specific response to drought, and climate-growth relationships during the period 1997–2018. The drought response of provenances was determined by four drought parameters: resistance, recovery, resilience, and relative resilience. Based on the standardized precipitation index, ten years with extreme and severe drought were identified for all trial sites. Considerable differences in radial growth, wood characteristics, and drought response parameters among silver fir provenances have been found. The provenances’ ranking by resistance, recovery, and resilience revealed that a number of provenances from Bulgaria, Italy, Romania, and Czech Republic placed in the top ranks in almost all sites. Additionally, there are provenances that combine high productivity and drought tolerance. The correlations between drought parameters and wood characters are positive, the most significant correlations being obtained between radial growth and resilience. Correlations between drought parameters and wood density were non-significant, indicating that wood density cannot be used as indicator of drought sensitivity. The negative correlations between radial growth and temperature during the growing season and the positive correlations with precipitation suggest that warming and water deficit could have a negative impact on silver fir growth in climatic marginal sites. Silvicultural practices and adaptive management should rely on selection and planting of forest reproductive material with high drought resilience in current and future reforestation programs. Full article

(This article belongs to the Special Issue Climate Change and Air Pollution Effects on Forest Ecosystems)

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Review

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17 pages, 1817 KiB

Open AccessReview

Valuing Forest Ecosystem Services. Why Is an Integrative Approach Needed?

by Gabriela Elena Baciu, Carmen Elena Dobrotă and Ecaterina Nicoleta Apostol

Forests 2021, 12(6), 677; https://doi.org/10.3390/f12060677 - 25 May 2021

Cited by 18 | Viewed by 4427

Abstract

Among the many types of terrestrial ecosystems, forests have some of the highest levels of biodiversity; they also have many interdependent economic, ecological and social functions and provide ecosystem services. They supply a range of tangible, marketable goods, as well as a variety of nonmarketable and intangible services derived from various forest functions. These translate into social, cultural, health and scientific benefits for people’s quality of life. However, because they cannot be traded on a market, nonmarketable and intangible services are often perceived as free, inexhaustible and, as a result, underestimated. The human–nature interaction has affected both nature (via resource consumption) and society (via development of human welfare and well-being). Decision-makers, both public and private, often manage natural capital for multiple aims. In recent years it has been found that the single, individual approach estimating the value for these goods and services is not able to provide information that generates and supports decisions and policies in complex areas of current relevance such as the constant loss of biodiversity, climate change and global warming in close connection with the need for social development and ensuring an acceptable level of well-being for the greatest part of humanity. An integrated assessment with advanced techniques and methods using a pluralist framework of a heterogeneous set of values is considered a better approach to the valuation of such complex nature of the ecosystem goods and services. This assessment should take into account both costs and benefits trade-off issues among the multiple uses of ecosystem goods and/or services, especially the relationships between them and how they influence or determine the economic, social and cultural development of society. It should also consider the estimation of the complex inverse effect, from society to nature, whose goods and services can be diminished to exhaustion by the extensive and intensive anthropization of natural ecosystems with major impact on the number and quality of goods and services provided by ecosystems. Research has shown that applying an integrative assessment approach that utilizes tools developed by sustainability sciences could be an important component of future environmental policy making. Full article

(This article belongs to the Special Issue Climate Change and Air Pollution Effects on Forest Ecosystems)

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