Forests

26 pages, 1327 KB

Open AccessArticle

Forest Tourism and the Use of AI Technologies Towards Clean and Safe Environments: The Cases of Turkey, Lithuania, and Morocco

by Dalia Perkumienė, Ahmet Atalay and Larbi Safaa

Forests 2025, 16(10), 1615; https://doi.org/10.3390/f16101615 - 21 Oct 2025

Viewed by 482

Abstract

The rapidly expanding use of artificial intelligence (AI) technologies in recent years presents significant opportunities for achieving sustainable, clean, and safe environmental objectives. This study aims to comprehensively examine the potential use of AI technologies for clean and safe environmental goals in forest [...] Read more.

The rapidly expanding use of artificial intelligence (AI) technologies in recent years presents significant opportunities for achieving sustainable, clean, and safe environmental objectives. This study aims to comprehensively examine the potential use of AI technologies for clean and safe environmental goals in forest tourism areas in Turkey, Lithuania, and Morocco, and to conduct comparative analyses specific to each target country. The research was conducted using a qualitative methodology within a case study design. In line with purposive sampling principles, the sample was limited to a total of 72 participants from the three countries (24 from Turkey, 24 from Lithuania, and 24 from Morocco). To identify expert opinions relevant to the study objectives, semi-structured interviews were conducted across the three country samples, and the collected data were processed and analyzed using NVivo 14 software. The data were transformed into findings through descriptive analysis and content analysis. The results indicate that AI technologies are employed in forest tourism areas for diverse purposes and objectives related to clean and safe environmental management. In Turkey, AI applications are primarily directed toward proactive measures addressing pressing environmental issues, such as forest fires. In Lithuania, as an EU member state, AI technologies are utilized in a more strategic, institutional, and comprehensive manner across multiple areas and objectives. In contrast, Morocco appears to lag in AI adoption, focusing on international collaborations to enhance digital infrastructure and facilitate technology transfer. Full article

(This article belongs to the Special Issue Forest Recreation and Tourism)

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22 pages, 6012 KB

Open AccessArticle

Assessment of Individual Tree Crown Detection Based on Dual-Seasonal RGB Images Captured from an Unmanned Aerial Vehicle

by Shichao Yu, Kunpeng Cui, Kai Xia, Yixiang Wang, Haolin Liu and Susu Deng

Forests 2025, 16(10), 1614; https://doi.org/10.3390/f16101614 - 21 Oct 2025

Viewed by 423

Abstract

Unmanned aerial vehicle (UAV)-captured RGB imagery, with high spatial resolution and ease of acquisition, is increasingly applied to individual tree crown detection (ITCD). However, ITCD in dense subtropical forests remains challenging due to overlapping crowns, variable crown size, and similar spectral responses between [...] Read more.

Unmanned aerial vehicle (UAV)-captured RGB imagery, with high spatial resolution and ease of acquisition, is increasingly applied to individual tree crown detection (ITCD). However, ITCD in dense subtropical forests remains challenging due to overlapping crowns, variable crown size, and similar spectral responses between neighbouring crowns. This paper investigates to what extent the ITCD accuracy can be improved by using dual-seasonal UAV-captured RGB imagery in different subtropical forest types: urban broadleaved, planted coniferous, and mixed coniferous–broadleaved forests. A modified YOLOv8 model was employed to fuse the features extracted from dual-seasonal images and perform the ITCD task. Results show that dual-seasonal imagery consistently outperformed single-seasonal datasets, with the greatest improvement in mixed forests, where the F1 score range increased from 56.3%–60.7% (single-seasonal datasets) to 69.1%–74.5% (dual-seasonal datasets) and the AP value range increased from 57.2%–61.5% to 70.1%–72.8%. Furthermore, performance fluctuations were smaller for dual-seasonal datasets than for single-seasonal datasets. Finally, our experiments demonstrate that the modified YOLOv8 model, which fuses features extracted from dual-seasonal images within a dual-branch module, outperformed both the original YOLOv8 model with channel-wise stacked dual-seasonal inputs and the Faster R-CNN model with a dual-branch module. The experimental results confirm the advantages of using dual-seasonal imagery for ITCD, as well as the critical role of model feature extraction and fusion strategies in enhancing ITCD accuracy. Full article

(This article belongs to the Section Forest Inventory, Modeling and Remote Sensing)

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20 pages, 2817 KB

Open AccessArticle

Wildfire Detection from a Drone Perspective Based on Dynamic Frequency Domain Enhancement

by Xiaohui Ma, Yueshun He, Ping Du, Wei Lv and Yuankun Yang

Forests 2025, 16(10), 1613; https://doi.org/10.3390/f16101613 - 21 Oct 2025

Viewed by 496

Abstract

In recent years, drone-based wildfire detection technology has advanced rapidly, yet existing methods still encounter numerous challenges. For instance, high background complexity leads to frequent false positives and false negatives in models, which struggle to accurately identify both small-scale fire points and large-scale [...] Read more.

In recent years, drone-based wildfire detection technology has advanced rapidly, yet existing methods still encounter numerous challenges. For instance, high background complexity leads to frequent false positives and false negatives in models, which struggle to accurately identify both small-scale fire points and large-scale wildfires simultaneously. Furthermore, the complex model architecture and substantial parameter count hinder lightweight deployment requirements for drone platforms. To this end, this paper presents a lightweight drone-based wildfire detection model, DFE-YOLO. This model utilizes dynamic frequency domain enhancement technology to resolve the aforementioned challenges. Specifically, this study enhances small object detection capabilities through a four-tier detection mechanism; improves feature representation and robustness against interference by incorporating a Dynamic Frequency Domain Enhancement Module (DFDEM) and a Target Feature Enhancement Module (C2f_CBAM); and significantly reduces parameter count via a multi-scale sparse sampling module (MS3) to address resource constraints on drones. Experimental results demonstrate that DFE-YOLO achieves mAP50 scores of 88.4% and 88.0% on the Multiple lighting levels and Multiple wildfire objects Synthetic Forest Wildfire Dataset (M4SFWD) and Fire-detection datasets, respectively, whilst reducing parameters by 23.1%. Concurrently, mAP50-95 reaches 50.6% and 63.7%. Comprehensive results demonstrate that DFE-YOLO surpasses existing mainstream detection models in both accuracy and efficiency, providing a reliable solution for wildfire monitoring via unmanned aerial vehicles. Full article

(This article belongs to the Section Natural Hazards and Risk Management)

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20 pages, 5059 KB

Open AccessArticle

Integrating Remote Sensing and Field Data to Quantify Mangrove Biomass Carbon Hotspots and Protection Gaps in Guangdong, China

by Di Dong, Huamei Huang, Qing Gao, Kang Li, Shengpeng Zhang and Ran Yan

Forests 2025, 16(10), 1612; https://doi.org/10.3390/f16101612 - 21 Oct 2025

Viewed by 578

Abstract

Mangroves are important blue carbon coastal ecosystems and play a crucial role in mitigating global climate change. However, fine spatial patterns of mangrove biomass carbon hotspots and protection gaps in Guangdong have not been quantified. In this study, we mapped mangrove biomass carbon [...] Read more.

Mangroves are important blue carbon coastal ecosystems and play a crucial role in mitigating global climate change. However, fine spatial patterns of mangrove biomass carbon hotspots and protection gaps in Guangdong have not been quantified. In this study, we mapped mangrove biomass carbon by integrating Sentinel-2 satellite imagery and field survey data from Guangdong’s coastlines acquired in 2023 for the first time. Using the Getis-Ord Gi* spatial statistic method, we identified the mangrove biomass carbon hotspots and highlighted protection gaps in mangrove conservation. The total mangrove biomass carbon of Guangdong was estimated to be 1,209,305.68 Mg C (with a mean density of 80.56 Mg C/ha), with Zhanjiang containing the highest carbon stock, accounting for over half of the total. Nature reserves supported higher mean biomass carbon (83.03 Mg C/ha), compared with areas outside nature reserves (77.99 Mg C/ha), underscoring their important role in enhancing mangrove carbon storage. The overlapping area between the mangrove biomass carbon stock hotspot areas and the nature reserves is 71.62 km², accounting for 51.13% of the total hotspot area. In terms of mangrove biomass carbon stocks, the main protection gaps in Guangdong are distributed in Anpu Gang, the region south of Zhanjiang, Shuidong Harbor, Pearl River Estuary, Kaozhou Yang, and Yifengxi Port. Our findings reveal the spatial heterogeneity of mangrove carbon stocks in Guangdong and provide novel insights for optimizing mangrove management and spatial planning of nature reserves for conservation and restoration. Full article

(This article belongs to the Section Forest Inventory, Modeling and Remote Sensing)

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29 pages, 28659 KB

Open AccessArticle

Assessing Anthropogenic Impacts on the Carbon Sink Dynamics in Tropical Lowland Rainforest Using Multiple Remote Sensing Data: A Case Study of Jianfengling, China

by Shijie Mao, Mingjiang Mao, Wenfeng Gong, Yuxin Chen, Yixi Ma, Renhao Chen, Miao Wang, Xiaoxiao Zhang, Jinming Xu, Junting Jia and Lingbing Wu

Forests 2025, 16(10), 1611; https://doi.org/10.3390/f16101611 - 20 Oct 2025

Viewed by 549

Abstract

Aboveground biomass (AGB) is a key indicator of forest structure and carbon sequestration, yet its dynamics under concurrent anthropogenic disturbances remain poorly understood. This study investigates the spatiotemporal dynamics and driving mechanisms of AGB in the Jianfengling tropical lowland rainforest (JFLTLR) within Hainan [...] Read more.

Aboveground biomass (AGB) is a key indicator of forest structure and carbon sequestration, yet its dynamics under concurrent anthropogenic disturbances remain poorly understood. This study investigates the spatiotemporal dynamics and driving mechanisms of AGB in the Jianfengling tropical lowland rainforest (JFLTLR) within Hainan Tropical Rainforest National Park (NRHTR) from 2015 to 2023. Six machine learning models—Extreme Gradient Boosting (XGBoost), Gradient Boosting Machine (GBM), Support Vector Machine (SVM), k-Nearest Neighbors (KNN), Decision Tree (DT), and Random Forest (RF)—were evaluated, with RF achieving the highest accuracy (R² = 0.83). Therefore, RF was employed to generate high-resolution annual AGB maps based on Sentinel-1/2 data fusion, field surveys, socio-economic indicators, and topographic variables. Human pressure was quantified using the Human Influence Index (HII). Threshold analysis revealed a critical breakpoint at ΔHII ≈ 0.1712: below this level, AGB remained relatively stable, whereas beyond it, biomass declined sharply (≈−2.65 mg·ha⁻¹ per 0.01 ΔHII). Partial least squares structural equation modeling (PLS-SEM) identified plantation forests as the dominant negative driver, while GDP (−0.91) and road (−1.04) exerted strong indirect effects through HII, peaking in 2019 before weakening under ecological restoration policies. Spatially, biomass remained resilient within central core zones but declined in peripheral regions associated with road expansion. Temporally, AGB exhibited a trajectory of decline, partial recovery, and renewed loss, resulting in a net reduction of ≈ 0.0393 × 10⁶ mg. These findings underscore the urgent need for a “core stabilization–peripheral containment” strategy integrating disturbance early-warning systems, transportation planning that minimizes impacts on high-AGB corridors, and the strengthening of ecological corridors to maintain carbon-sink capacity and guide differentiated rainforest conservation. Full article

(This article belongs to the Special Issue Modelling and Estimation of Forest Biomass)

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17 pages, 3183 KB

Open AccessArticle

Modeling Carbon Sequestration and Economic Returns Using 3-PG in the FSC-Certified Simcoe County Forest

by Fanxuan Sun and Rasoul Yousefpour

Forests 2025, 16(10), 1610; https://doi.org/10.3390/f16101610 - 20 Oct 2025

Viewed by 502

Abstract

In this study, we developed three forest management scenarios for Simcoe County Forest in Southern Ontario, Canada, using the Physiological Principles Predicting Growth (3-PG) model to simulate future forest growth and carbon dynamics. The focus was on four main species: Red pine ( [...] Read more.

In this study, we developed three forest management scenarios for Simcoe County Forest in Southern Ontario, Canada, using the Physiological Principles Predicting Growth (3-PG) model to simulate future forest growth and carbon dynamics. The focus was on four main species: Red pine (Pinus resinosa), White pine (Pinus strobus), Sugar maple (Acer saccharum), and Red oak (Quercus rubra). We parameterized, calibrated, and validated parameters of the 3-PG model for these four species and applied the model to evaluate the performance of management scenarios incorporating timber and carbon values in Simcoe County Forest. The first scenario, “business as usual,” maintained the existing management plan for the forest, ensuring stable timber income (531.2 CAD/hectare) and moderate carbon sequestration. The second scenario aimed to optimize management for the highest timber Net Present Value (NPV), with half of the trees harvested before 2030, followed by gradual thinning over 15 years. This approach yielded the highest financial returns (1634.1 CAD/hectare) but the lowest carbon sequestration potential. The third scenario integrated carbon certification, emphasizing the retention of sugar maple stands over the next 20 years. This scenario produced financial returns (580.2 CAD/hectare) higher than the “business as usual” scenario, while saving 49.33 tons of biomass per hectare. Overall, this study provides a reference for the implementation of carbon sequestration projects. Full article

(This article belongs to the Special Issue Economic Research on Forest Ecosystem Services)

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28 pages, 11071 KB

Open AccessArticle

Forest Cover in the Congo Basin: Consistency Evaluation of Seven Datasets

by Solène Renaudineau, Frédéric Frappart, Marc Peaucelle, Valentine Sollier, Jean-Pierre Wigneron, Philippe Ciais and Bertrand Ygorra

Forests 2025, 16(10), 1609; https://doi.org/10.3390/f16101609 - 20 Oct 2025

Viewed by 580

Abstract

Tropical forests play an essential role in the carbon and water cycles of terrestrial ecosystems, but they are increasingly threatened by human activities and climate change. For places where ground observations are scarce, like in Equatorial Africa, remote sensing is a key source [...] Read more.

Tropical forests play an essential role in the carbon and water cycles of terrestrial ecosystems, but they are increasingly threatened by human activities and climate change. For places where ground observations are scarce, like in Equatorial Africa, remote sensing is a key source of information for monitoring the temporal and spatial dynamics of forests over large areas. Several Earth Observation-based global maps were developed in recent decades using different definitions of the land-use/land-cover (LULC) classes. While such products are widely used for monitoring land use and planning land management, the consistency of these LULC maps for the Congo Basin has never been analyzed and quantified at the ecosystem level. Here, we selected seven of the most-used global maps and analyzed their consistency over the Congo Basin. After reclassification into forest/non-forest masks and spatial resampling, we assessed the agreement and disagreement percentage across the different tropical ecoregions of Africa, from moist forest to miombo, including savanna. The datasets showed differences in forest area as a function of spatial resolution, with higher forest area levels at coarser resolutions (e.g., from 74.1% to 88.5% forest cover when upscaling the GLCLU from 30 m to 1 km over the Congo Basin). A higher agreement between the datasets was found for forest area over moist forest (between 88.18% and 99.38%) in comparison to savanna (32.82%–99.84%) and miombo (53.83%–99.7%). These discrepancies led to large differences in forest cover, varying from a net loss of 205,704 km² to a net gain of 50,726 km² over 2001–2019 depending on the dataset used. This study draws attention to the uncertainty associated with these products with regard to forests, particularly in regions of biological importance, such as the miombo and savanna regions, which remain poorly understood. Indeed, the two major uncertainties affecting the quality of LULC products are related to the different spatial resolutions and biological definition of “forest” adopted by each product. Full article

(This article belongs to the Section Forest Inventory, Modeling and Remote Sensing)

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19 pages, 1222 KB

Open AccessArticle

Soil Respiration Variability Due to Litter and Micro-Environment During the Cold-Temperature Season in a Temperate Monsoon Deciduous Forest

by Jaeseok Lee

Forests 2025, 16(10), 1608; https://doi.org/10.3390/f16101608 - 20 Oct 2025

Viewed by 369

Abstract

In cool temperate regions, soil respiration (Rs) data collected during the cold season is limited due to freezing and snow. This leads to a lack of understanding of Rs characteristics during the cold season and for ecosystems with long winters, it can significantly [...] Read more.

In cool temperate regions, soil respiration (Rs) data collected during the cold season is limited due to freezing and snow. This leads to a lack of understanding of Rs characteristics during the cold season and for ecosystems with long winters, it can significantly impact the annual carbon flux estimation. In this study, Rs data were collected from temperate deciduous forests to understand the characteristics of Rs values in the cold temperature season. To reflect spatial variation in Rs, five points were selected with different levels of litter layer development, ranging from Chamber 1 (almost no litter) to Chamber 5 (thick litter). Rs, air temperature (Ta) and rainfall, soil temperature (Ts) and soil moisture content (SMC) were collected every 30 min at each measurement point. As the litter layer developed, Ts tended to increase, but SMC tended to decrease, revealing that the degree of litter layer development had a clear effect on Ts and SMC. Rs showed a relatively high exponential correlation with Ts. However, the Rs−SMC functional relationship exhibited no correlation. Therefore, while the Ts-Rs functional equation can be used in the Rs calculator during the cold season, the SMC-Rs function would be suitable for use. Also, these deferent litter layers, TS, and SMC affected the Rs. The total Rs during the measurement period was various from 0.60 t C ha⁻¹ for a thin litter layer to 1.88 t C ha⁻¹ for a thick layer. This range of values may be appropriate for estimating Rs during the cold season in temperate regions. Also, the average across all plots was 6.05, ranging from 4.93 in no litter to 8.23 in thick litter layer. Full article

(This article belongs to the Special Issue Belowground Carbon Flux in Forests: Carbon Emission, Storage and Beyond)

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19 pages, 5496 KB

Open AccessArticle

Screening and Validation of Stable Reference Genes for Real-Time Quantitative PCR in Indocalamus tessellatus (Munro) P. C. Keng Under Multiple Tissues and Abiotic Stresses

by Xiaoqing Hu, Chenjie Zhou, Junhao Pan, Wangqing Wu, Shuang Wu, Xiaofang Yan, Chenxin Wang and Qianggen Zhu

Forests 2025, 16(10), 1607; https://doi.org/10.3390/f16101607 - 20 Oct 2025

Cited by 1 | Viewed by 480

Abstract

Indocalamus tessellatus (Munro) P. C. Keng is a bamboo species with significant economic and ecological value, and exhibits considerable resistance to abiotic stresses. However, systematic evaluation of reference genes for gene expression analysis in this species is lacking. Analysis of multi-tissue transcriptomes yielded [...] Read more.

Indocalamus tessellatus (Munro) P. C. Keng is a bamboo species with significant economic and ecological value, and exhibits considerable resistance to abiotic stresses. However, systematic evaluation of reference genes for gene expression analysis in this species is lacking. Analysis of multi-tissue transcriptomes yielded 3801 relatively stable genes; from these, we selected eleven new candidates along with nine widely adopted reference genes. We then evaluated these candidates under four conditions: drought (15% PEG-6000), salt (200 mM NaCl), waterlogging (root submergence in water), and a multi-tissue panel (leaf, leaf sheath, culm, shoot, and root). Under stress, early and sustained time points were sampled to capture dynamic transcriptional responses. Expression stability was assessed using geNorm, NormFinder, BestKeeper, and ΔCt, and results were integrated with RefFinder to generate comprehensive stability rankings for each condition. The most stable reference genes were condition-dependent: MD10B and PP2A under drought, eIF1A and Ite23725 under salt stress, PP2A and eIF4A under waterlogging, and 60S and UBP1 across different tissues. Notably, commonly used genes such as UBI and Actin7 were less stable. Peroxidase (POD) was used as a validation marker because it is a known stress-responsive gene, providing a sensitive readout of normalization accuracy. Validation confirmed that selecting suitable reference genes is essential for dependable expression quantification. These findings provide a robust set of reference genes for qRT-PCR studies in I. tessellatus, supporting future molecular and functional research in bamboo. Full article

(This article belongs to the Special Issue Forest Tree Genetics and Breeding in Response to Different Threats: 2nd Edition)

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19 pages, 18673 KB

Open AccessArticle

Unexpected Long-Term Forest Experiments: A Case on the Island of Porto Santo, Madeira

by Leónia Nunes, Natália Nunes, Sara Freitas and Francisco Castro Rego

Forests 2025, 16(10), 1605; https://doi.org/10.3390/f16101605 - 20 Oct 2025

Viewed by 459

Abstract

The aim of this study was to assess the long-term adaptation and growth performance of 50 species introduced in 1991 on the island of Porto Santo, Madeira Archipelago, in order to guide afforestation and soil restoration under the island’s arid conditions, especially in [...] Read more.

The aim of this study was to assess the long-term adaptation and growth performance of 50 species introduced in 1991 on the island of Porto Santo, Madeira Archipelago, in order to guide afforestation and soil restoration under the island’s arid conditions, especially in biosphere reserves. The experiment was conducted in Alentejo, Pico Juliana and Matinho, three sites with different types of elevation, soil and exposure. A total of 502 experimental units (five plants each) were established with a completely randomized design in the three sites in 1991 to test the adaptation of 50 species from Mediterranean, African, Australian and American dry climates. Plants were grown in local nursery conditions and planted in rows with 1 × 4 m spacing. Soil properties were analyzed, and survival and growth (height and stem diameter) were monitored in 1991, 1992 and 2025. An analysis of variance was performed for the whole experiment, with the three sites showing significant differences in survival and height among species and sites thirty-four years after the planting. Some species showed high survival and growth, such as Pinus halepensis, Eucalyptus sideroxylon and Casuarina cunninghamiana. Others, like Schinus terebinthifolius and Thevetia neriifolia, showed good adaptation, and invasive behavior at the best sites, but their performance was strongly dependent on site conditions, with Alentejo being the most limiting site. This study demonstrates the long-term value of forest experiments and of long-term monitoring, providing rare data on species adaptation under semi-arid insular conditions. The findings support future afforestation strategies focusing on ecological suitability and invasiveness risk. Full article

(This article belongs to the Special Issue Growth and Stand Dynamics of Unmanaged and Managed Forests Under Global Change)

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15 pages, 2059 KB

Open AccessArticle

Stand Density Effects on Stem Diseases and Mortality in Spruce and Pine Forests

by Lina Beniušienė, Gintautas Mozgeris, Donatas Jonikavičius, Girmantė Jurkšienė, Benas Šilinskas and Ričardas Beniušis

Forests 2025, 16(10), 1606; https://doi.org/10.3390/f16101606 - 19 Oct 2025

Viewed by 416

Abstract

Norway spruce (Picea abies (L.) H. Karst.) and Scots pine (Pinus sylvestris L.) are among the most valuable tree species in the Lithuanian forests. Pure stands, which comprise approximately one-quarter of Lithuania’s forest area, provide an important framework for studying tree [...] Read more.

Norway spruce (Picea abies (L.) H. Karst.) and Scots pine (Pinus sylvestris L.) are among the most valuable tree species in the Lithuanian forests. Pure stands, which comprise approximately one-quarter of Lithuania’s forest area, provide an important framework for studying tree responses to thinning and susceptibility to species-specific diseases and damage. This study investigated stem health and quality in two experimental Scots pine stands (32 and 39 years old) and four experimental Norway spruce stands (36–43 years old) to assess the influence of the initial stand density and thinning intensity. Each stand consisted of five plots with different initial densities and was subjected to varying thinning regimes from stand establishment. Tree locations were mapped using the pseudolite-based positioning system TerraHärp, and local tree density was calculated. Stem health and damage were assessed using ICP-Forests methodology. Our results showed that across initial densities of 1000–4400 trees ha⁻¹, tree dimensions (diameter and height) were similar, regardless of thinning intensity. The highest levels of stem damage and competition-induced mortality occurred in the densest, unthinned stands, with deer browsing and scraping from fallen trees being the most common damage agents. In contrast, thinned stands exhibited a higher incidence of stem rot (Heterobasidion annosum (Fr.) Bref.), particularly for Norway spruce. Finally, stand density alone did not consistently explain the patterns of tree mortality in either the pine or spruce stands. These findings suggest that cultivating Scots pine and Norway spruce at lower initial densities with minimal thinning may reduce the damage and losses caused by fungal infection. Finally, novel techniques, such as the pseudolite-based positioning system for geolocating trees and drone imaging for assessing tree health, have proven valuable in facilitating field surveys. Full article

(This article belongs to the Section Forest Health)

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23 pages, 5798 KB

Open AccessArticle

Fungal and Bacterial Communities of the Red Turpentine Beetle (Dendroctonus valens LeConte) in the Great Lakes Region, USA

by Andrew J. Mann, Rin M. Barnum, Benjamin W. Held, Kathryn E. Bushley, Brian H. Aukema and Robert A. Blanchette

Forests 2025, 16(10), 1604; https://doi.org/10.3390/f16101604 - 19 Oct 2025

Viewed by 489

Abstract

Fungi and bacteria associated with bark beetles can facilitate successful tree colonization, and, in some cases, these fungi act as pathogens of trees. The red turpentine beetle (RTB, Dendroctonus valens) is a bark beetle native to North America that colonizes stressed pines, [...] Read more.

Fungi and bacteria associated with bark beetles can facilitate successful tree colonization, and, in some cases, these fungi act as pathogens of trees. The red turpentine beetle (RTB, Dendroctonus valens) is a bark beetle native to North America that colonizes stressed pines, rarely killing healthy trees. The fungal communities associated with RTB adults, larval galleries, and control tree phloem from red pine (Pinus resinosa) and white pine (P. strobus) forests in the Great Lakes region of the United States were characterized using both culture-independent and culture-dependent methods. Similarly, the bacterial communities associated with RTB adults in the same region were characterized using a culture-independent method. There were significant differences between the adult beetle fungal communities and the tree-based fungal communities. Culture-independent sequencing of RTB adults showed high abundances of the fungal order Filobasidiales (red pine: 28.71% relative abundance, white pine: 6.91% relative abundance), as well as the bacterial orders Enterobacterales (red pine: 53.72%, white pine: 22.15%) and Pseudomonadales (red pine: 15.86%, white pine: 12.91%). In contrast, we isolated high amounts of fungi in the orders Pleosporales (red pine: 21.79%, white pine: 15.90%) and Eurotiales (red pine: 15.38%, white pine: 16.51%) from the adult beetles by culturing. Culture-independent sequencing of beetle galleries yielded high abundances of fungi in the orders Helotiales (red pine: 22.23%, white pine: 23.21%), whereas culture-based isolation from the same galleries yielded high amounts of Eurotiales (red pine: 17.91%, white pine: 17.91%), Hypocreales (red pine: 16.42%, white pine: 16.42%), and Ophiostomatales (red pine: 23.39%, white pine: 23.39%). This contrasts with the culture-independent method, where, likely due to limitations in the sequencing method, the Ophiostomatales accounted for only around 2% of the fungi from RTB galleries in both pine species. We observed a high species-level diversity of Ophiostomatales associated with RTB, isolating 14 species from the Great Lakes region. Leptographium terebrantis, a species that has been described in association with RTB throughout the United States, was the most common species (e.g., >35% of the Ophiostomatales relative abundance in red pine environments and >14% of the Ophiostomatales relative abundance in the white pine environment). This study enhances our understanding of RTB-associated fungi and bacteria in the beetle’s native range at both the community and species levels. Full article

(This article belongs to the Special Issue Diagnosing and Managing Forest and Tree Diseases: Advances, Challenges and Strategies)

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21 pages, 3380 KB

Open AccessArticle

Refining Carbon Balance Estimates of Harvested Wood Products: A Generalizable Tier-3 Production Approach for China

by Xiaobiao Zhang

Forests 2025, 16(10), 1603; https://doi.org/10.3390/f16101603 - 19 Oct 2025

Viewed by 525

Abstract

The carbon pool of harvested wood products (HWPs) is an essential part of the national greenhouse gas inventory. Developing a Tier-3 method for the Intergovernmental Panel on Climate Change (IPCC) Production Approach (PA) enhances the accuracy of HWP carbon balance assessments and removal [...] Read more.

The carbon pool of harvested wood products (HWPs) is an essential part of the national greenhouse gas inventory. Developing a Tier-3 method for the Intergovernmental Panel on Climate Change (IPCC) Production Approach (PA) enhances the accuracy of HWP carbon balance assessments and removal estimates. This is crucial as the PA is a mandatory IPCC approach. A major challenge for developing a Tier-3 PA is the absence of an effective way to allocate HWP production to domestic and overseas end uses, precluding the application of Tier-3 PA in most countries in the world. Here, we integrated the Eora multi-regional input–output (MRIO) model, which effectively allocates HWPs to these end uses into the PA to create a generalizable Tier-3 PA. Using China-produced HWPs from 1990 to 2020 as a case study, we report that these HWPs accumulated a carbon stock of 3376 MtCO₂e by 2020 and provided a carbon sink of 221 MtCO₂e yr⁻¹ from 2016 to 2020. Construction, furniture, other solid HWPs, sanitary and household paper, and other paper products accumulated 1244, 226, 1032, 0, and 189 MtCO₂e, respectively. China’s trade partners consumed 14% of China-produced HWPs and contributed to 13% of the total carbon stock and 15% of the total carbon sink. The generalizable Tier-3 PA is applicable for countries with limited end-use data, and thus enhances their HWP carbon removal estimates. Our first-ever comprehensive PA-based assessment of overseas HWP consumption and carbon removal supports IPCC methodological improvement and future HWP-related international negotiations and mitigation actions. Full article

(This article belongs to the Section Forest Ecology and Management)

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20 pages, 3412 KB

Open AccessArticle

Influence of Eucalyptus Plantation on Soil Microbial Characteristics in Severely Degraded Land of Leizhou Peninsula

by Jundi Zhong, Hanyuan Xu, Zina Chen, Kaiyan Yang, Shenghong Xiao and Xunzhi Ouyang

Forests 2025, 16(10), 1602; https://doi.org/10.3390/f16101602 - 18 Oct 2025

Viewed by 394

Abstract

Soil microorganisms are important decomposers in soil, and they play important roles in litter degradation, nutrient cycle and balance, soil physicochemical property improvement, and soil fertility maintenance. To understand the influence of Eucalyptus plantations on the growth, reproduction, and activity of soil microorganisms [...] Read more.

Soil microorganisms are important decomposers in soil, and they play important roles in litter degradation, nutrient cycle and balance, soil physicochemical property improvement, and soil fertility maintenance. To understand the influence of Eucalyptus plantations on the growth, reproduction, and activity of soil microorganisms in severely degraded land, the Leizhou Peninsula in tropical China was selected as the research area. The vegetation restoration types of Eucalyptus urophylla × grandis planted in its severely degraded red soil areas (ES: Eucalyptus–shrub, EG: Eucalyptus–grass, and ED: Eucalyptus–Dicranopteris pedata (Houtt.) Nakaike) were studied, and the nearby natural vegetation types (S: shrub, G: grass, and D: Dicranopteris pedata) served as control groups. The microbial characteristics of different vegetation restoration types were compared, and the influence of Eucalyptus plantations on the growth, reproduction, and activity of soil microorganisms in severely degraded red soil areas was discussed by setting up sample plots for investigation, sample determination, and statistical analysis. The structure of soil microorganisms differed significantly between Eucalyptus vegetation restoration (ER) and natural vegetation restoration without Eucalyptus (NER). Key organic decomposers, including bacterial genera such as Candidatus Solibacter (ER: 1.2 ± 0.4% vs. NER: 0.9 ± 0.1%), Candidatus Koribacter (ER: 1.0 ± 0.4% vs. NER: 0.7 ± 0.1%), and Edaphobacter (ER: 0.9 ± 0.1% vs. NER: 0.4 ± 0.1%), as well as fungal genera such as Rhizophagus (ER: 0.1 ± 0.0% vs. NER: 0.0 ± 0.0%), Paxillus (ER: 0.1 ± 0.0% vs. NER: 0.0 ± 0.0%), and Pisolithus (ER: 0.1 ± 0.0% vs. NER: 0.0 ± 0.0%), exhibited a significantly higher relative richness and a broader distribution in ER compared to NER (p < 0.05). Soil microbial biomass carbon, nitrogen and phosphorus (MBC, MBN, MBP), community structure (keystone taxa and symbiosis network complexity), and functional genes (for growth, reproduction, and decomposition) in ER, especially in ES, were significantly higher than in NER. This study illustrated that Eucalyptus plantations, especially ES types, can promote the growth and reproduction of soil organic decomposers, improve microbial metabolic and biological activities, and increase functional diversity and interactions among microorganisms, thus accelerating the cycle of soil carbon, nitrogen, and phosphorus nutrients, improving soil quality and fertility, and accelerating the recovery of degraded soil fertility. In areas with serious soil degradation and where natural vegetation restoration is difficult, planting Eucalyptus, especially while guiding the understory vegetation to develop into the shrub vegetation type, is an effective vegetation restoration model. Full article

(This article belongs to the Section Forest Soil)

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23 pages, 4122 KB

Open AccessArticle

Enhancing Cold Tolerance Evaluation in Camellia sinensis and Camellia japonica Through Multimethod Analysis and Predictive Modeling

by Woo-Hyeong Yang, Seong-Hyeon Yong, Do-Hyun Kim, Kwan-Been Park, Seung-A Cha, Ji-Hyeon Lee, Seon-A Kim, Jenna Jung and Myung-Suk Choi

Forests 2025, 16(10), 1601; https://doi.org/10.3390/f16101601 - 18 Oct 2025

Viewed by 422

Abstract

Cold stress is a critical factor restricting the cultivation of subtropical evergreen species such as Camellia sinensis and C. japonica in temperate climates. This study aimed to develop an integrated framework for evaluating cold tolerance by combining visual assessment, electrolyte leakage (EL), Evans [...] Read more.

Cold stress is a critical factor restricting the cultivation of subtropical evergreen species such as Camellia sinensis and C. japonica in temperate climates. This study aimed to develop an integrated framework for evaluating cold tolerance by combining visual assessment, electrolyte leakage (EL), Evans blue staining, and nonlinear regression modeling. All experiments were conducted with n = 3 samples per treatment, and statistical analyses were performed at a significance level of α = 0.05. Under freezing treatment at −6 °C, C. japonica exhibited faster and more severe damage, including leaf curling and vein darkening, compared to C. sinensis. Electrolyte leakage and cell death increased rapidly in C. japonica, and a sharp rise in cell death occurred in both species when EL exceeded 55%. Logistic regression of EL data estimated LT₅₀ values of −10.96 °C for C. sinensis and −9.38 °C for C. japonica, while EL Temp₅₀ values were −9.59 °C and −8.97 °C, respectively, indicating higher membrane stability in C. sinensis. The difference in LT₅₀ between the two species was statistically significant (p < 0.05). Biochemical and heatmap analyses from 25 °C to −12 °C showed that C. sinensis maintained higher chlorophyll, antioxidant activity, and sugar levels, reflecting stronger cold tolerance. In contrast, C. japonica accumulated more proline and MDA, indicating higher stress sensitivity and membrane damage. This study presents a reproducible, quantitative framework for evaluating cold tolerance in Camellia species, offering valuable insights for breeding and expanding cultivation under climate change. Full article

(This article belongs to the Special Issue Abiotic and Biotic Stress Responses in Trees Species)

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20 pages, 3225 KB

Open AccessArticle

Forecasting the Impact of Climate Change on Tetraclinis articulata Distribution in the Mediterranean Using MaxEnt and GIS-Based Analysis

by Kaouther Mechergui, Umer Hayat, Muhammad Hammad Ahmad, Somayah Moshrif Alamri, Eman Rafi Alamery, Khadeijah Yahya Faqeih, Maha Abdullah Aldubehi and Wahbi Jaouadi

Forests 2025, 16(10), 1600; https://doi.org/10.3390/f16101600 - 18 Oct 2025

Viewed by 459

Abstract

Climate change threatens Tetraclinis articulata, a Mediterranean plant endangered by habitat loss, logging, and aridification. This study used the MaxEnt model to analyze factors affecting its distribution under current and future climate scenarios (SSP1-2.6 to SSP5-8.5) for 2040–2100, highlighting its vulnerability to [...] Read more.

Climate change threatens Tetraclinis articulata, a Mediterranean plant endangered by habitat loss, logging, and aridification. This study used the MaxEnt model to analyze factors affecting its distribution under current and future climate scenarios (SSP1-2.6 to SSP5-8.5) for 2040–2100, highlighting its vulnerability to drought and urgent conservation needs. Results showed that: (a) the model demonstrated excellent predictive power with an AUC of 0.92; (b) the highly suitable habitat for T. articulata is projected to expand by 6.5%–6.7% (5.24–5.38 million km²) by 2100 under SSPs 2-4.5, 3-7.0, and 5-8.5, compared to current conditions (6.1%, 4.92 million km²); (c) the centroid of suitable habitats shifts from northwest Algeria (1.394° N, 33.538° E) to various locations under future climate scenarios: west Morocco (SSP1-2.6, −3.429° S, 33.588° E), east Tunisia (SSP2-4.5, 11.091° N, 32.501° E), northwest Morocco (SSP3-7.0, −1.947° S, 34.098° E), and southwest Morocco (SSP5-8.5, −2.985° S, 34.707° E); (d) key environmental variables influencing T. articulata distribution include annual precipitation (bio12, 41.7%), mean annual temperature (bio1, 27.9%), and precipitation during the driest month (bio14, 16.1%). This study concluded that climate change significantly influenced the distribution of T. articulata in the Mediterranean, highlighting the urgent need for conservation strategies to mitigate the risk of local extinction driven by both anthropogenic activities and climate impacts. Full article

(This article belongs to the Special Issue Climate Change Impacts on Forest Dynamics: Use of Modern Technology)

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15 pages, 4896 KB

Open AccessArticle

Typhoon-Driven Shifts in Dissolved Organic Carbon Across Mangrove Ecosystems of Varying Restoration Age

by Youwei Lin, Shengjie Han, Ruina Liu, Yunfeng Shi, Xiaoya Zhang, Zongbo Peng, Zhen Ni and Mingzhong Liu

Forests 2025, 16(10), 1599; https://doi.org/10.3390/f16101599 - 17 Oct 2025

Viewed by 301

Abstract

Mangrove ecosystems are vital to coastal carbon cycling, yet their response to extreme climatic events remains underexplored. This study assesses dissolved organic carbon (DOC) dynamics across four ecosystem types—primary mangrove, restored (5-year and 8-year), and bare land—during three typhoons (Maliksi, Yagi, and Trami) [...] Read more.

Mangrove ecosystems are vital to coastal carbon cycling, yet their response to extreme climatic events remains underexplored. This study assesses dissolved organic carbon (DOC) dynamics across four ecosystem types—primary mangrove, restored (5-year and 8-year), and bare land—during three typhoons (Maliksi, Yagi, and Trami) that occurred in 2024. DOC concentrations (mol m⁻² s⁻¹) were measured across pre-, during-, and post-event phases and analyzed using boxplots, heatmaps, and ANOVA. Results show that primary mangroves maintained stable DOC levels, indicating strong biogeochemical resilience. Restored plots exhibited phase-dependent DOC variability, with older restoration age linked to improved carbon retention. Bare land showed consistently high DOC release, especially post-event, reflecting vulnerability to hydrological stress. DOC peaks occurred after typhoons, suggesting delayed carbon mobilization via microbial turnover and detrital input. These findings highlight the role of restoration age and vegetation cover in stabilizing coastal carbon under intensifying climatic extremes. Full article

(This article belongs to the Section Forest Ecology and Management)

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18 pages, 4385 KB

Open AccessArticle

Transcriptomic Analysis of Anthocyanin Degradation in Salix alba Bark: Insights into Seasonal Adaptation and Forestry Applications

by Hong-Yong Wang, Xing-Ju Liu, Meng-Zhen Yin, Sheng-Jia Cui, Hai-Yong Liang and Zhen-Hua Xu

Forests 2025, 16(10), 1598; https://doi.org/10.3390/f16101598 - 17 Oct 2025

Viewed by 341

Abstract

Anthocyanins, key flavonoid-derived secondary metabolites, not only confer diverse pigmentation but also function in photoprotection, antioxidative defense, and cold acclimation. In woody species, bark anthocyanin turnover is tightly linked to environmental adaptation, stress resilience, and ornamental traits, yet its molecular regulation remains largely [...] Read more.

Anthocyanins, key flavonoid-derived secondary metabolites, not only confer diverse pigmentation but also function in photoprotection, antioxidative defense, and cold acclimation. In woody species, bark anthocyanin turnover is tightly linked to environmental adaptation, stress resilience, and ornamental traits, yet its molecular regulation remains largely unresolved. Here, we investigated Salix alba L. bark by integrating anthocyanin quantification, transcriptome profiling, and weighted gene co-expression network analysis (WGCNA) to dissect the temporal dynamics and regulatory architecture of anthocyanin degradation. Anthocyanin content peaked at D2 (late December 2024), declined through D3 (mid-January 2025) and D4 (mid-February 2025), and partially rebounded at D5 (early March 2025), coinciding with peak expression of structural genes LAC1/2, POD1/2, and BGLU10. These enzymes co-expressed with multiple transcription factors, including MYB, bHLH, and WRKY families, forming putative core modules. Functional enrichment indicated that differentially expressed genes were enriched in redox processes, glycoside hydrolysis, flavonoid metabolism, and hormone signaling, suggesting a degradation mechanism mediated by reactive oxygen species, glycosidic cleavage, and hormone–transcription factor interplay. This study provides the first comprehensive framework of bark anthocyanin degradation in white willow, advancing the understanding of pigment dynamics, gene–environment crosstalk, and breeding strategies for ornamental woody plants. Full article

(This article belongs to the Special Issue Adaptive Physiology of Forest Plants: Mechanisms, Strategies, and Responses to Environmental Challenges)

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29 pages, 8130 KB

Open AccessArticle

Cross-Linked Gelatine as a Binder in Wood Fibre Composites for Topsoil Protection

by Janine Bösing, Alessandro Sorze and Sebastian Hirschmüller

Forests 2025, 16(10), 1597; https://doi.org/10.3390/f16101597 - 17 Oct 2025

Viewed by 277

Abstract

This study aimed to develop novel sustainable composites based on cross-linked gelatine and wood fibres for use as a topsoil cover in forestry and agricultural applications. Different compositions were prepared by varying the proportions of gelatine, wood fibres, and tannic acid (the cross-linking [...] Read more.

This study aimed to develop novel sustainable composites based on cross-linked gelatine and wood fibres for use as a topsoil cover in forestry and agricultural applications. Different compositions were prepared by varying the proportions of gelatine, wood fibres, and tannic acid (the cross-linking agent). Water absorption analysis revealed that compositions containing 12% wood fibres exhibited the highest absorption values (300% after 24 h). Including wood fibres was crucial in limiting the cross-sectional shrinkage of the samples. Additionally, the wood fibres did not negatively impact the water vapour permeability values, which ranged from 0.5 to 3.5 × 10⁻⁸ kg/(Pa · h · m). Tensile tests revealed that the samples’ tensile strength ranged from 4 to 17 MPa, whereas Young’s modulus depended more on climatic conditions, with values reaching 2700 MPa in dry conditions and 300 MPa in wet conditions (samples conditioned at 20 °C and 95% relative humidity). Furthermore, after 46 weeks of outdoor exposure, the produced composites demonstrated good dimensional stability and reduced mass loss, particularly in the composition with the highest wood fibre and tannic acid content. Full article

(This article belongs to the Special Issue Advances in Testing the Biological Durability and Quality Assurance of Wood-Based Materials and Products)

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16 pages, 5792 KB

Open AccessArticle

Effects of Humac and Alginite Fertilization on Mite Communities (Acari, Mesostigmata) Under Post-Agricultural Land Conditions

by Jacek Malica, Cezary Krzysztof Urbanowski, Jacek Kamczyc, Abubakar Yahaya Tama, Maciej Skorupski and Vilém Podrázský

Forests 2025, 16(10), 1596; https://doi.org/10.3390/f16101596 - 17 Oct 2025

Viewed by 392

Abstract

Afforestation of post-agricultural land is one of the most important challenges of modern forestry, posed by economic demand and climate protection. Unfortunately, stands introduced on such degraded soils are not sustainable and their productive value is limited. The present study tested the effects [...] Read more.

Afforestation of post-agricultural land is one of the most important challenges of modern forestry, posed by economic demand and climate protection. Unfortunately, stands introduced on such degraded soils are not sustainable and their productive value is limited. The present study tested the effects of two substances—Humac and Alginite—on the community structure of mesostigmatid mites colonizing plots overgrown by Platanus × acerifolia (Aiton) Willd, also comparing them with the mite communities of arable field and 64-year-old stands of Pinus sylvestris L. and Quercus robur L. growing on post-agricultural land. A total of 306 mite individuals were recorded, belonging to 45 taxa and 14 families. The results indicate a moderately positive effect of Humac fertilization on the mite communities studied. A similar impact has not been demonstrated for Alginite. In contrast, all parameters studied (density, species richness and diversity of mite communities) reached the highest values in the P. sylvestris stand. Humac application harmonizes Mesostigmata mite community structures between young and older stands and may be considered a beneficial practice for the afforestation of former agricultural land. Full article

(This article belongs to the Section Forest Biodiversity)

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17 pages, 5543 KB

Open AccessArticle

TASNet-YOLO: An Identification and Classification Model for Surface Defects of Rough Planed Bamboo Strips

by Yitong Zhang, Rui Gao, Min Ji, Wei Zhang, Wenquan Yu and Xiangfeng Wang

Forests 2025, 16(10), 1595; https://doi.org/10.3390/f16101595 - 17 Oct 2025

Viewed by 453

Abstract

After rough planing, defects such as wormholes and small patches of green bark residue and decay are often overlooked and misclassified. Strip-like defects, including splinters and chipped edges, are easily confused with the natural bamboo grain, and a single elongated defect is frequently [...] Read more.

After rough planing, defects such as wormholes and small patches of green bark residue and decay are often overlooked and misclassified. Strip-like defects, including splinters and chipped edges, are easily confused with the natural bamboo grain, and a single elongated defect is frequently fragmented into multiple detection boxes. This study proposes a modified TASNet-YOLO model, an improved detector built on YOLO11n. Unlike prior YOLO-based bamboo defect detectors, TASNet-YOLO is a mechanism-guided redesign that jointly targets two persistent failure modes—limited visibility of small, low-contrast defects and fragmentation of elongated defects—while remaining feasible for real-time production settings. In the backbone, a newly designed TriMAD_Conv module is introduced as the core unit, enhancing the detection of wormholes as well as small-area defects such as green bark residue and decay. The additive-gated C3k2_AddCGLU is further integrated at selected C3k2 stages. The combination of additive interaction and CGLU improves channel selection and detail retention, highlighting differences between splinters and chipped edges and bamboo grain strips, thereby reducing false positives and improving precision. In the neck, the neck replaces nearest-neighbor upsampling and CBS with SNI-GSNeck to improve cross-scale alignment and fusion. Under an acceptable real-time budget, predictions for splinters and chipped edges become more contiguous and better aligned to edges, while wormholes predictions are more circular and less noisy. Experiments on our in-house dataset (8445 bamboo-strip defect images) show that, compared with YOLO11n, the proposed model improves detection accuracy by 5.1%, achieves 106.4 FPS, and reduces computational costs by 0.4 GFLOPs per forward pass. These properties meet the throughput demand of 2 m/s conveyor lines, and the compact model size and compute footprint make edge deployment straightforward for fast online screening and preliminary quality grading in industrial production. Full article

(This article belongs to the Special Issue Transforming Wood into Smart Materials: Innovations in Processing and Application)

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14 pages, 1770 KB

Open AccessArticle

Differences in the Amount of Litterfall and Mercury Concentration in Litterfall Leaves of Typical Forest Ecosystems in China

by Shuyu Han, Jingwei Zhang, Ran He, Donghuan Liu, Xiang Niu, Bing Wang and Zhangwei Wang

Forests 2025, 16(10), 1594; https://doi.org/10.3390/f16101594 - 17 Oct 2025

Viewed by 324

Abstract

Mercury, a global pollutant with both persistence and high toxicity, has remained a focal point in environmental science research over the past half-century. As a key pathway in the terrestrial mercury cycle, plants actively assimilate gaseous elemental mercury (Hg⁰) through leaf [...] Read more.

Mercury, a global pollutant with both persistence and high toxicity, has remained a focal point in environmental science research over the past half-century. As a key pathway in the terrestrial mercury cycle, plants actively assimilate gaseous elemental mercury (Hg⁰) through leaf stomata, constituting a critical pathway for terrestrial mercury cycling. The litterfall mercury concentration serves as a biological indicator to quantify vegetation’s mercury interception capacity, providing essential data for global mercury cycle modelling. To investigate this, 15 sampling sites throughout the country were selected, and litterfall was collected monthly for 12 consecutive months to determine the litterfall amount, composition, and leaf mercury dynamics. The results revealed that annual litterfall production ranged from 1.10–8.56 t·hm⁻², with leaf components dominating (45.58%–89.11%). Furthermore, three seasonal litterfall patterns emerged: unimodal, bimodal, and irregular. Regarding mercury, the mercury concentration in leaf litter exhibited a certain seasonal variation trend, with the mercury content in leaves in most areas being higher in autumn and winter. Specifically, the mercury concentration in litterfall showed a significant negative correlation with latitude and a significant positive correlation with air temperature, precipitation, and litterfall amount (p < 0.05). Additionally, the concentration of Hg in dying leaves exhibited some geographical variations. Full article

(This article belongs to the Section Forest Ecophysiology and Biology)

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18 pages, 2181 KB

Open AccessArticle

Assessment of Genetic Variation in Natural Populations of Hippophae rhamnoides L. from Kazakhstan Using Retrotransposon-Based Markers

by Asem Tumenbayeva, Ainur Turzhanova, Saule Magzumova, Tatiana Vdovina, Aidar Sumbembayev, Yeskendir Satekov, Vladislav Shevtsov, Olesya Raiser, Damelya Tagimanova and Oxana Khapilina

Forests 2025, 16(10), 1593; https://doi.org/10.3390/f16101593 - 17 Oct 2025

Viewed by 543

Abstract

Analysis of the genetic diversity of natural populations of economically valuable plants is important for conservation and selection strategies. In this study, the genetic diversity of 11 natural populations of Hippophae rhamnoides L.—sea buckthorn from different regions of Kazakhstan—was studied using Inter-Primer Binding [...] Read more.

Analysis of the genetic diversity of natural populations of economically valuable plants is important for conservation and selection strategies. In this study, the genetic diversity of 11 natural populations of Hippophae rhamnoides L.—sea buckthorn from different regions of Kazakhstan—was studied using Inter-Primer Binding Site Polymorphism (iPBS) markers based on conserved sequences of tRNA primer-binding sites (PBSs) that initiate retrotransposon replication. Universal PBS primers yielded reproducible and informative amplicons, forming unique profiles for each sample. Analysis of molecular variance showed that 60% of the total genetic variation was due to intrapopulation differences and 40% was due to interpopulation differentiation. The highest genetic diversity was found in the Shetlasty and Tersayryk sea buckthorn populations, whereas the Karatal and Topkain populations were characterised by minimal values, although unique alleles were observed in the latter population, indicating possible adaptation to local environmental conditions or genetic isolation. Principal coordinate analysis, UPGMA clustering, and Bayesian structure analysis (K = 4) confirmed geographical structuring. This study provides insights into the genetic structure of sea buckthorn populations in Kazakhstan and demonstrates the effectiveness of iPBS markers for assessing intraspecific diversity. The obtained results provide a basis for the conversation of H. rhamnoides gene pool and underscore the need for both in situ conservation of genetically rich populations and ex situ protection of vulnerable groups. Full article

(This article belongs to the Section Genetics and Molecular Biology)

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11 pages, 1175 KB

Open AccessArticle

Comparative Analysis of Glutathione Metabolism in Pb-Tolerant and Pb-Sensitive Salix integra Genotypes Under Lead Stress

by Ruifang Huang, Xudong He, Hongling Wang, Shizheng Shi and Baosong Wang

Forests 2025, 16(10), 1592; https://doi.org/10.3390/f16101592 - 17 Oct 2025

Viewed by 550

Abstract

Lead (Pb) is a widespread environmental pollutant that severely threatens plant growth and development. While the mechanisms of Pb uptake and accumulation have been extensively studied in herbaceous plants, the glutathione (GSH)-mediated biochemical responses in woody species remain largely unexplored. This knowledge gap [...] Read more.

Lead (Pb) is a widespread environmental pollutant that severely threatens plant growth and development. While the mechanisms of Pb uptake and accumulation have been extensively studied in herbaceous plants, the glutathione (GSH)-mediated biochemical responses in woody species remain largely unexplored. This knowledge gap limits our understanding of the detoxification strategies of perennial plants with high phytoremediation potential. In this study, two Salix integra clones (P336 and P646) with contrasting Pb tolerance were used to investigate the temporal regulation of GSH metabolism under Pb stress. P336 displayed both early and sustained increases in cysteine (Cys), GSH, ascorbic acid (AsA), phytochelatins (PCs), and the activities of γ-ECS and APX, conferring stronger antioxidant and detoxification capacity than P646. Notably, glutathione reductase (GR) activity remained unchanged in both clones, indicating that GSH homeostasis was maintained mainly through de novo synthesis rather than GR-mediated recycling. These findings demonstrate that Pb tolerance in P336 is achieved through γ-ECS–driven de novo GSH biosynthesis, which sustains both the AsA–GSH cycle and PC synthesis for efficient ROS detoxification and Pb sequestration. By providing the first detailed evidence of GSH-centered detoxification dynamics in a woody phytoremediant, this study advances our mechanistic understanding of Pb tolerance in S. integra and highlights its application potential in the phytoremediation of Pb-contaminated environments. Full article

(This article belongs to the Section Genetics and Molecular Biology)

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26 pages, 3870 KB

Open AccessArticle

Elevational Patterns of Plant Species Richness: Insights from Western Himalayas

by Abhishek Kumar, Meenu Patil, Pardeep Kumar and Anand Narain Singh

Forests 2025, 16(10), 1591; https://doi.org/10.3390/f16101591 - 16 Oct 2025

Viewed by 1355

Abstract

Understanding the patterns and drivers of species distribution has remained a central theme for biogeographical, conservation, and ecological research. This study aims to investigate the elevational patterns of plant species richness and compare the observed species richness with the predictions of the mid-domain [...] Read more.

Understanding the patterns and drivers of species distribution has remained a central theme for biogeographical, conservation, and ecological research. This study aims to investigate the elevational patterns of plant species richness and compare the observed species richness with the predictions of the mid-domain effect (MDE) null model. By combining information from field observations and the published literature, we compiled a comprehensive database of the elevational distribution of plant species for three protected areas in the Western Himalayas. We used generalised linear model (GLM) and null model simulations to explore the elevational patterns of plant species richness. Our study revealed simple linear to complex non-linear patterns depending on the location and range of the elevational gradient. While non-linear unimodal patterns were common, a linear decreasing pattern was also observed. The observed species richness showed consistent deviations from the predictions of the mid-domain effect null model, suggesting that factors beyond the range constraints shape species richness patterns. These observations indicate that richness patterns are not solely generated by random processes, rather climatic gradients, ecological interactions, and topographic heterogeneity can shape these patterns. Understanding these factors can aid in predicting and managing the impacts of ongoing environmental changes on Himalayan biodiversity. Full article

(This article belongs to the Section Forest Biodiversity)

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23 pages, 14512 KB

Open AccessArticle

Drivers of Bird Diversity in the Pearl River Delta National Forest Urban Agglomeration, Guangdong Province, China

by Nana Bai, Yingchun Fu, Tingting He, Si Zhang, Dongping Zhong, Jia Sun and Zhenghui Yin

Forests 2025, 16(10), 1590; https://doi.org/10.3390/f16101590 - 16 Oct 2025

Viewed by 617

Abstract

To mitigate the threats posed by habitat fragmentation due to rapid urbanization on bird diversity, this study introduces an innovative framework for analyzing the synergistic effects of habitat quality (HQ), ecological network connectivity (ENC), and bird richness (BR) in the Pearl River Delta [...] Read more.

To mitigate the threats posed by habitat fragmentation due to rapid urbanization on bird diversity, this study introduces an innovative framework for analyzing the synergistic effects of habitat quality (HQ), ecological network connectivity (ENC), and bird richness (BR) in the Pearl River Delta National Forest Urban Agglomeration (PRDNFUA). The framework, based on a stratified ecological network perspective that distinguishes between urban agglomeration and urban core areas, incorporates different types of ecological corridors (interactive corridors and self-corridors), providing a novel approach for effectively quantifying and spatially visualizing the temporal and spatial evolution of the “HQ–ENC–BR” synergy. By integrating geographic detectors through ternary plot analysis combined with a zonation model, this study identified the synergetic effects of HQ and ENC on BR observed during 2015–2020 and proposed strategies for optimizing “HQ–ENC–BR” synergy. The results indicate that between 2015 and 2020, (1) the Pearl River Estuary and coastal areas are hotspots for bird distribution and also represent gaps in ecological network protection. (2) The positive synergistic effects between ecological network structure (HQ, ENC) and function (BR) have gradually strengthened and are stronger than the effects of individual factors; this synergy is especially significant in urban agglomerations and interactive corridors and is particularly pronounced in the northern cities. (3) The area overlap between the optimized ecological network and bird richness hotspots will increase by approximately 78.2%. The proposed ecological network optimization strategies are scientifically sound and offer valuable suggestions for improving bird diversity patterns in the PRDNFUA. These findings also provide empirical support for the United Nations Sustainable Development Goals (SDG 11: Sustainable Cities and Communities; SDG 15: Life on Land). Full article

(This article belongs to the Special Issue Biodiversity in Forests: Management and Monitoring for Conservation—2nd Edition)

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18 pages, 3097 KB

Open AccessArticle

Moso Bamboo Invasion Enhances Soil Infiltration and Water Flow Connectivity in Subtropical Forest Root Zones: Mechanisms and Implications

by Tianheng Zhao, Lin Zhang and Shi Qi

Forests 2025, 16(10), 1589; https://doi.org/10.3390/f16101589 - 16 Oct 2025

Viewed by 427

Abstract

Plant roots influence soil infiltration by altering its properties like porosity and bulk density, which are essential for ecohydrological cycles. Moso bamboo (Phyllostachys edulis), using its well-developed underground root system, invades neighbor forest communities, thereby influencing root characteristics and soil properties. [...] Read more.

Plant roots influence soil infiltration by altering its properties like porosity and bulk density, which are essential for ecohydrological cycles. Moso bamboo (Phyllostachys edulis), using its well-developed underground root system, invades neighbor forest communities, thereby influencing root characteristics and soil properties. Although Moso bamboo invasion may alter soil hydrology, its specific impact on soil infiltration capacity and water flow connectivity remains unclear. This work took a fir forest (Cunninghamia lanceolata), mixed fir and bamboo forest, and a bamboo forest which represent three different degrees of invasion: uninvaded, partially invaded, and completely invaded, respectively, as study objects, using double-ring dyeing infiltration method to measure soil infiltration capacity and calculating water flow connectivity index for the root zone. To assess the effects of soil properties and root characteristics on soil infiltration capacity and water flow connectivity, we employed random forest and structural equation modeling. The analysis revealed that Moso bamboo invasion significantly enhanced soil infiltration capacity. Specifically, in partially invaded forests, the initial infiltration rate, stable infiltration rate, and average infiltration rate increased by 31.5%, 26.1%, and 28.5%, respectively. In completely invaded forests, the corresponding increases were 6.6%, 35.6%, and 28.5%. Also, Moso bamboo invasion increased water flow connectivity of root zone, compared to the uninvaded forest, the water flow connectivity index increased by 29.4% in the completely invaded forest and by 15.6% in the partially invaded forest. The marked increase in fine root biomass density (RBD1), fine root length density (RLD1), soil organic carbon (SOC), and non-capillary pores (NCP) and the decrease in soil bulk density (SBD) followed by Moso bamboo invasion effectively improved water flow connectivity and soil infiltration capacity. The analysis identified that RBD1, RLD1, NCP, and SBD as the key drivers of soil infiltration capacity, whereas the water flow connectivity index was controlled mainly by SOC, NCP, RLD1, and RBD1. These findings help clarify the mechanistic pathways of Moso bamboo’s effects on soil infiltration. Full article

(This article belongs to the Section Forest Soil)

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17 pages, 3282 KB

Open AccessArticle

Comparing Spatial Analysis Methods for Habitat Selection: GPS Telemetry Reveals Methodological Bias in Raccoon Dog (Nyctereutes procyonoides) Ecology

by Sumin Jeon, Soo Kyeong Hwang, Yeon Woo Lee, Jihye Son, Hyeok Jae Lee, Chae Won Yoon, Ju Yeong Lee, Dong Kyun Yoo, Ok-Sik Chung and Jong Koo Lee

Forests 2025, 16(10), 1588; https://doi.org/10.3390/f16101588 - 16 Oct 2025

Viewed by 577

Abstract

Recent issues that have emerged in regard to raccoon dog (Nyctereutes procyonoides) include interaction with humans and disease transmission. Therefore, understanding their habitat characteristics and preferences is crucial in the effort to limit conflicts with humans. A total of thirteen raccoon [...] Read more.

Recent issues that have emerged in regard to raccoon dog (Nyctereutes procyonoides) include interaction with humans and disease transmission. Therefore, understanding their habitat characteristics and preferences is crucial in the effort to limit conflicts with humans. A total of thirteen raccoon dogs were captured from three regions in South Korea, each with distinct habitat characteristics. GPS trackers were attached for tracking the raccoon dogs’ movements. Utilizing GPS tracking data, Kernel Density Estimation (KDE), Minimum Convex Polygon (MCP), and Jacobs Index were applied to learn more about the habitat preferences of the raccoon dogs. According to the results, the habitat composition ratios for KDE and MCP showed that forests had the largest proportion. However, a habitat composition ratio similar to the land proportion of the area that they inhabit indicated that raccoon dogs had the ability to adapt to various habitats. Jacobs Index analysis revealed different habitat selection patterns compared to KDE and MCP, with forests showing neutral to negative selection despite comprising large proportions of home ranges. Our results highlight important methodological considerations when inferring habitat preferences from spatial data, suggesting that multiple analytical approaches provide complementary insights into animal space use. Full article

(This article belongs to the Section Forest Biodiversity)

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25 pages, 774 KB

Open AccessArticle

Understanding How Generation Z Students in Forest Sciences and Landscape Architecture Perceive Ecosystem Services in Urban Garden Forests

by Hoi-Eun Roh, Jang-Hwan Jo, Yu-Ji Jang and Jung-Won Sung

Forests 2025, 16(10), 1587; https://doi.org/10.3390/f16101587 - 16 Oct 2025

Viewed by 427

Abstract

This study investigates how university students perceive the ecosystem services provided by gardens, utilizing Q methodology to categorize subjective viewpoints and analyze distinct perception types. Thirty-two students majoring in forest and landscape architecture at Wonkwang University (Iksan, Republic of Korea) participated, sorting 30 [...] Read more.

This study investigates how university students perceive the ecosystem services provided by gardens, utilizing Q methodology to categorize subjective viewpoints and analyze distinct perception types. Thirty-two students majoring in forest and landscape architecture at Wonkwang University (Iksan, Republic of Korea) participated, sorting 30 Q-statements each for provisioning, regulating, cultural, and supporting services. Principal component analysis identified three factors for provisioning and regulating services, and two factors for cultural and supporting services. The findings reveal that students’ perceptions are primarily based on generalized, idealized expectations, while their understanding of specific practices, such as food production, distribution, and community economic integration, remains insufficient. This indicates that their perceptions are more conceptual than practical, reflecting themes such as eco-friendly resource sharing, environmental regulation, nature experience, biodiversity enhancement, and sustainability. These results suggest the need for enhanced educational efforts to improve students’ understanding of the role of ecosystem services in urban contexts. The study highlights the importance of bridging the gap between theoretical knowledge and practical recognition to foster more comprehensive perceptions, ultimately informing future garden design, management strategies, and environmental education programs. Full article

(This article belongs to the Special Issue Ecosystem Services of Urban Forests—2nd Edition)

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20 pages, 7756 KB

Open AccessArticle

A Novel System for the Characterization of Bark Macroscopic Morphology for Central European Woody Species

by László Zoltán and Márton Korda

Forests 2025, 16(10), 1586; https://doi.org/10.3390/f16101586 - 15 Oct 2025

Viewed by 978

Abstract

Accurate identification of deciduous woody species in winter is challenging, and the misidentification can lead to ecological and management damage. This study aims to substantiate a diagnostic system for woody species based on macromorphological bark characters. First, we reviewed the literature on bark-based [...] Read more.

Accurate identification of deciduous woody species in winter is challenging, and the misidentification can lead to ecological and management damage. This study aims to substantiate a diagnostic system for woody species based on macromorphological bark characters. First, we reviewed the literature on bark-based species identification to assess existing approaches and their limitations. Building on this, we identified informative macromorphological features of bark through both literature analysis and our experiences. These characters cover all developmental phases, including twigs, young bark, and mature bark, and are supported by new diagnostic terminology. Using this framework, we compiled a character set for 115 Central European woody taxa, providing practical, primarily qualitative traits that can be applied directly in the field. Finally, we developed and tested “Single-access Keys” as an alternative to conventional dichotomous keys, demonstrating their effectiveness in enabling flexible and rapid species recognition, even under atypical conditions or when only partial observations are possible. Our results highlight the value of bark macromorphology as a diagnostic tool and emphasize its potential for advancing thematic identification keys, as well as digital applications in forestry, taxonomy, and ecological monitoring. Full article

(This article belongs to the Section Forest Biodiversity)

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Forests, Volume 16, Issue 10 (October 2025) – 114 articles

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