Cerne Journal: Top 10 Most Accessed Articles in February 2026
Posted on 2026-02-271- HIGH DIVERSITY OF ARBUSCULAR MYCORRHIZAL FUNGI IN TWO FORESTRY ECOSYSTEMS FROM CENTRAL AND NORTHERN COSTA RICA
Dawa Méndez-Álvarez, María Rodríguez-Solís, Martin Hassan Polo-Marcial, Luis Alberto Lara-Pérez, William Watson-Guido, Sofía Jiménez-Poveda, Dagoberto Arias-Aguilar, William Rivera-Méndez
Abstract
Background: Arbuscular mycorrhizal fungi (AMF) generate a symbiotic relationship with most terrestrial plants, influencing the dynamics and functioning of ecosystems. There are few studies on the diversity of these fungi associated with forest species and in different types of ecosystems. The objective of this study was to characterize the diversity and structure of AMF communities associated with Cordia alliodora and Swietenia macrophylla in two forestry ecosystems with different types of management in Costa Rica. For this purpose, rhizosphere and soil samples were collected from 10 trees at random, spores and sporocarps were isolated and characterized, AMF abundance, richness and diversity were determined, and a physicochemical analysis of the soil was carried out.
Results: Fifty-seven AMF morphospecies belonging to five orders, 10 families and 15 genera were identified, with a predominance of Diversisporales and Glomerales; we report 15 new geographic records of AMF increasing the richness to 76 species and by 24% the Glomeromycota’s richness in Costa Rica. There were no significant differences in total spore abundance between the two forest species, however, there were significant differences in the modes of formation and species composition. Conclusions: The alpha diversity analysis showed that rare species largely explain the differences between the sites, and the AMF community structure was influenced by edaphic factors such as pH and available phosphorus content. These types of studies highlight the importance of considering the identity and diversity of AMF associated with forest species of commercial interest and ecological importance in different types of ecosystems.
Keywords:
Agroforestry system, Santa Rosa National Park, Glomeromycota, Laurel, Mahogany
2- FOUR-DECADE ANALYSIS OF FIRE BEHAVIOR IN THE BRAZILIAN CAATINGA BIOME 1985-2023
Mauricio Alejandro Perea-ArdilaAbstract
Background: The Caatinga, unique in northeastern Brazil, has species adapted to the semi-arid climate. Recurrent fires put its biodiversity at risk, highlighting the need for urgent measures to protect this fragile ecosystem. This study analyzed four decades of fire behavior in the Caatinga biome (1985-2023) using data from the MapBiomas Fire project and spatial analysis, revealing an alarming increase in fire activity, which affected approximately 10.9 million hectares (≈12.74% of the biome). Results: Showed an increasing trend in the frequency and intensity of fires, with critical peaks between August and November, particularly in October where historical maximums were reached in the period 2015-2023 (48.1%). Spatial distribution showed significant concentrations in the western and southern regions of the biome, especially in the states of Bahia and Piauí, mainly linked to human activities. The temporal analysis revealed a progressive accumulation of burned areas, with a notable increase towards the end of the period studied. The recurrence of fires presented a heterogeneous distribution, with up to 39 events at the same point in critical areas, affecting mainly forest formations and herbaceous-bush vegetation.
Conclusion: The research underlines the vulnerability of the Caatinga ecosystem to these recurrent events, highlighting the urgent need to implement land management and fire management measures, including continuous monitoring programs and regional adaptive strategies that combine agricultural productivity with ecosystem conservation. This study contributes to the understanding of fire dynamics in tropical semiarid biomes, providing crucial information for decision-making in conservation and sustainable management policies.
Keywords: Burned area; Fires; Vegetation cover; Semiarid; MapBiomas.
3- DETERMINATION OF FOREST ROAD CUT SLOPE SURFACE MATERIAL TYPES USING MACHINE LEARNING METHODS IN UAV DATA
Tunahan Çınar, Yılmaz Türk, Abdurrahim Aydın, Remzi Eker
Abstract
Background: The cost of forest roads is practically estimated by determining the Surface Material Types (SMT). Experts determine SMT by classifying soil, loose soil, and rocky surface material classes (%) through in-situ measurements, which are both costly and time-intensive. This study aims to reduce cost and time loss by evaluating the effectiveness of high-resolution remote sensing (RS) data in determining SMT. Conducted on a forest road in Konuralp region of Düzce district in Türkiye, the study involved experts classifying the road’s Soil, Loose Soil and Rocky surface material classes (%) and collecting high-resolution RS data using UAV. The RS data was processed through Random Forest (RF) and Support Vector Machine (SVM) algorithms to classify the surface material types, and their accuracy was assessed using the Kappa Coefficient, Overall Accuracy (%) and Conditional Kappa. The images were clipped at 20-meter intervals for detailed analysis. The RS data classifications were then compared with in-situ measurements using statistical analyses Index-of-Agreement (IA).
Results: The RF algorithm made the best identification, although the classification of the Loose Soil class was more difficult for both algorithms compared to the other classes. Both algorithms highest accuracy in identifying the Rocky class.
Conclusions: This study proposes methods to reduce time loss in cost calculations and enhance the use of RS images for estimating forest road costs.
Keywords: Random Forest, Support Vector Machine, Remote Sensing, Classification Algorithms
4- QUALITY OF WOOD AND BARK OF EUCALYPTUSCLONES CULTIVATED FOR MEDIUM DENSITY FIBERBOARD PRODUCTION
Stéffany Lima Araujo, Gabriela Goldner Gimenez, Luana Bento Protázio, Thayanne Caroline Castor Neto, Daniela Andrade Neves de Rezende, Daniella Flávia Said Heid Schettini Silva, Maria Naruna Félix de Almeida, João Gabriel Missia da Silva, Graziela Baptista Vidaurre
Abstract
Background: Although bark is often considered undesirable in industrial applications, it is an integral part of the tree and is always present. The objective of this study was to evaluate the quality of wood and bark of Eucalyptus clones cultivated for medium density fiberboard production.Results: Bark proportion ranged from 8.22% to 10.25%, and heartwood from 26.98% to 36.16%. The basic density of wood ranged from 455 to 502 kg·m⁻³, wood with bark from 447 to 483 kg·m⁻³, and bark from 342 to 368 kg·m⁻³. Bark showed higher extractive (8.59% to 13.21%) and holocellulose (67.70% to 71.43%) contents and lower lignin content (18.20% to 19.99%) compared to wood. pH values ranged from 4.40 to 4.75, being higher in bark. Ash content was significantly higher in bark (1.64% to 2.21%) than in wood (0.18% to 0.29%). The inclusion of bark in wood did not significantly affect density, pH, or chemical composition, indicating its technical feasibility for MDF panel production.Conclusion: The inclusion of bark in the wood of Eucalyptus clones did not cause significant changes in basic density, chemical composition, pH, or ash content, confirming its technical feasibility for MDF panel production. The most affected properties due to the presence of bark were extractive and ash contents.
Keywords: lignocellulosic materials, engineered wood panels, residue utilization, biomass quality
5- BIRD COMMUNITY IN A MOUNTAIN ECOTONAL LANDSCAPE: HOW IS THE DISTRIBUTION BETWEEN DIFFERENT PHYTOPHYSIOGNOMIES?
Aloysio Souza de Moura, Ewerton de Carvalho, Felipe Santana Machado,Dalmo Arantes Barros, José Roberto Soares Scolforo, Marco Aurélio Leite Fontes
Abstract
Background: The mountainous ecotonal regions of Brazil have a high diversity of species due to the sharing of faunal and floristic elements with adjacent biomes. These areas are preserved on a mesoscale and play a crucial role in biodiversity conservation. This study aims to analyze bird community distribution within an ecotonal region based on phytophysiognomies, focusing on species richness, composition, and seasonality. Additionally, it seeks to estimate species diversity through richness estimators and identify bioindicator species for each environment using statistical models. Direct observations were carried out in 18 areas representing primary environments/phytophysiognomies during two distinct seasons.
Results: 324 bird species from 60 families were recorded, including six species listed as threatened. The species accumulation curves did not reach asymptote, with a greater number of species for the summer. The distribution of species in the landscape was considered unique for each physiognomy and species composition. The INDVAL analysis found Serpophaga nigricans as an anthropogenic species, suggesting an adaptation of the species to areas with human activities, such as the tourist waterfall regions in this area.
Conclusion: The distribution of birds in the mountainous ecotonal landscape showed the importance of environments as they are unique in each phytophysiognomy, highlighting the importance for hosts of endemic, rare and endangered species.
Keywords: Distribution; Environments; Biogeography; Hotspot areas; Conservation.
6- RESCUE TECHNIQUES AND VEGETATIVE PROPAGATION OF EUCALYPTUS BENTHAMII MAIDEN & CAMBAGE
Hendrick da Costa de Souza, Ezequiel Gasparin, Adriana Maria Griebeler, Osmarino Pires dos Santos, Nathalia Pimentel, Henrique Araujo Barichello, Maristela Machado Araujo
Abstract
Background: The Eucalyptus genus is globally important for wood and non-wood product supply due to its fast growth, high productivity, and resistance to biotic and abiotic stresses. Eucalyptus benthamii is notably cultivated in subtropical regions, such as southern Brazil, due to its frost tolerance. However, the species exhibits low efficiency in adventitious rooting when propagated through clonal techniques. This study aimed to assess vegetative rescue techniques with different stump heights for E. benthamii and evaluate the effect of indolebutyric acid (IBA) 2024 on cutting rooting and seedlings development.
Results: The first trial was conducted in the field using a 2x3 factorial design to compare two stump heights (15 cm and 90 cm) and three collection intervals. The number of shoots and total cuttings were analyzed across three shoot height classes. The stump 15 cm, especially in the second collection (111 days after rescue), produced the highest number of shoots (73.7 shoots stump-1). The second trial, carried out in a nursery, assessed rooting responses to IBA concentrations (0, 1500, 3000, and 4500 mg L-1) in cuttings from both rescue techniques (stump 15 cm and 90 cm).IBA significantly improved cutting survival, rooting rate, and root development.
Conclusion: The stump at 15 cm was the most effective for shoot and cutting production in the field for vegetative rescue. Furthermore, an IBA concentration of 2800 mg L-1 is recommended for improving adventitious rooting and seedling production of E. benthamii.
Keywords: Adventitious rooting. Seedling production. Indolebutyric acid. Cutting propagation. Clonal forestry
7- POMOLOGICAL CHARACTERISTICS OF ARGAN TREE [ARGANIA SPINOSA (L.) SKEELS] GENETIC RESOURCES IN MOROCCO
Sezgin Ayan, Gülbahar Abdaloğlu, Said Laaribya, Esra Nurten Yer Çelik,Batın Mehmet Yer, Halim Ouhaddou, Assmaa Alaoui
Abstract
Background: The argan tree [Argania spinosa (L.) Skeels], native to Morocco, faces significant threats from climate change, leading to a shrinking natural distribution area. This study aimed to assess the diversity within argan tree populations and identify morphological differences and similarities among them by examining their fruits, seeds, and almonds.
Results: Researchers analyzed 32 morphological characteristics from 13 populations (40 samples each, totaling 520 materials) across diverse Moroccan coastal and inland habitats. Analysis of variance and multiple tests revealed significant morphological changes and high diversity among the populations. Notably, Cluster Analysis showed that the Aoulouz population formed a distinct group, highlighting its unique characteristics. Significant differences were also observed in fruit, seed, and almond diversity parameters.
Conclusion: The study confirms the high diversity of argan populations in Morocco’s natural distribution areas. These findings are crucial for developing integrated in situ and ex situ conservation strategies for the argan species. The research outputs will support the economic viability, ecological integrity, and long-term sustainability of this valuable and long-degraded species.Keywords: Fruit seed traits, eco-region, population, variation, endemic tree, morphological characteristics.
8- MULTIVARIATE MODELS BASED ON SPECTRAL DATA FOR THE CLASSIFICATION OF CHARCOALS PRODUCED AT DIFFERENT FINAL CARBONIZATION TEMPERATURES
Michael Douglas Roque Lima, Amanda Ribeiro de Melo, Joabel Raabe, Paulo Fernando Trugilho, Thiago de Paula Protásio, Paulo Ricardo Gherardi Hein
Abstract
Background: The prediction of apparent relative density (ARD) based on spectral data obtained in the near-infrared (NIR) region has not achieved high accuracy in the literature, emphasizing the need for alternatives to enable the use of NIR technology for classifying charcoal by ARD. In this context, the present study aimed to investigate the precision of NIR in estimating ARD classes for charcoal produced at different carbonization temperatures. Wood wastes from six tropical species (Dinizia excelsa, Licania sp., Brosimum gaudichaudii, Caryocar sp., Simaba guianensis, and Parkia sp.) were carbonized at four final temperatures (400, 500, 600, and 700 °C) under laboratory conditions. The spectral data collected from the radial and transverse surfaces of the charcoals were analyzed using Principal Component Analysis (PCA) and Partial Least Squares Discriminant Analysis (PLS-DA).
Results: While PCA was ineffective in distinguishing the ARD classes, PLS-DA demonstrated relevant accuracy for classification. The quality of the PLS-DA models varied depending on the final carbonization temperature and the surface from which the spectra were collected. Spectral data from the radial and transverse surfaces showed high accuracy in classifying charcoals (>70%) up to 500 °C for ARD. A global model with data from temperatures of 400–500 °C achieved accuracy rates of 74% (transverse) and 80% (radial).
Conclusion: Using NIR technology for ARD classification represents significant progress for the energy sector, especially in the pursuit of bio-reducers with suitable quality for industrial applications.
Keywords: Amazonian wastes; tropical woods; charcoal quality; NIRS; carbonization temperature
9- ASSESSMENT OF THE NEED FOR GROUND CONTROL POINTS IN AERIAL SURVEYS FOR ESTIMATING THE VOLUME OF STACKED TIMBER
Carlos Alberto Araújo Júnior, Rayssa Stéfany Ramos Machado Cordeiro
Abstract
Background: Our study aimed to investigate the feasibility of conducting aerial surveys without ground control points to estimate the volume of wood piles in planted areas. The data used in this study include both manual measurements (conventional method) and aerial imagery of 24 wood piles composed of Eucalyptus sp. The aerial surveys were conducted based on two flight plans: one performed at a flight height of 50 meters above the ground, with frontal and lateral overlaps of 70%, and other one conducted at a flight height of 80 meters above the ground, with frontal and lateral overlaps of 80%. Thirty-five ground control points (GCPs) were considered. Friedman and Nemenyi tests were applied to evaluate whether there were significant differences between the wood stockpile volume estimates obtained by the conventional method and those derived from the different surveys, with and without GCPs.
Results: The processing with the use of GCPs resulted in smaller RMSE values compared to those without GCPs. The volume estimates for each wood stockpile were similar, regardless of the presence or absence of GCPs. The Friedman test yielded a p-value of 0.3796, indicating that there is no evidence to suggest significant differences between the values obtained by different methods.Conclusion: The use of control points did not significantly improve the accuracy of volume estimates for wood piles placed in the field. Under the analyzed conditions, a low-cost drone can be used to estimate the volume of wood piles in the field without the need for ground control points.
Key words: Woodpile measurement; remotely piloted aircraft; remote sensing
10- WOODY SPECIES WITH HIGH WOOD DENSITY ARE MORE VULNERABLE TO GLOBAL CHANGE IN SOUTH CHINA
Guolin C. Li, Stavros D. Veresoglou
Abstract
Background: To cope with global change, plants shift their distributions. Rare species tend to shift their distribution more. Over 30% of the land is covered with woody species, which because of their longevity offer unique opportunities to monitor distribution shifts. The study addresses the following questions (1) how the distribution range of eight rare woody species is changing and how effectively the plants cope with the shift; (2) whether plant traits could predict those parameters. Maxent Distribution Modelling, was carried out for this purpose, on species observation records prior to 1980 under present climatic conditions and four future (CMIP5) scenarios. To assess how effectively plants cope with migration species observations after 1980 were assessed. Relationships with plant trait data on three traits were finally assessed. Results: The distribution ranges for four out of the eight species expanded northwards. Temperature driven (mostly through mean annual temperature which was ranked first for six out of the eight species) rather than precipitation (mean annual precipitation was ranked first only in two cases and in one case precipitation of the driest month was ranked third) driven variables described distribution shifts best. Wood density summarized well the susceptibility of those plants to climate change. There are many woody species in tropical and subtropical areas for which we have very little information available.
Conclusion:Subject to the small pool of species, a plant trait was identified, wood density, that could summarize responses to global change that could potentially be used as a tool in conservation ecology to prioritize conservation efforts.
Keywords: Biodiversity Hotspots; Extinction ecology; Species Distribution Shifts; Wood density; Wood’s Economic Spectrum