Cerne Journal: Top 10 Most Accessed Articles in September 2026

1- HOW DOES PYROLYSIS TEMPERATURE INFLUENCE THE PHYSICOCHEMICAL PROPERTIES OF BIOCHAR FROM Coffea canephora HUSK?

Louise Menezes Pimentel, Fabíola Martins Delatorre, Gabriela Fontes Mayrinck Cupertino, Merlindo Jacinto Manjate, Álison Moreira da Silva, Tayná Rebonato Oliveira, Bruna da Silva Cruz, Thiago de Paula Protásio, Ananias Francisco Dias Júnior.

Abstract

Background: Coffee cultivation is one of the most important agricultural activities in Brazil and generates large amounts of waste during fruit processing. Approximately 93% of the coffee fruit volume is discarded, with the husk being one of the main by-products. Inadequate disposal may cause environmental impacts, whereas its valorization through pyrolysis can provide a sustainable and value-added alternative. This study evaluated the effect of pyrolysis temperature (400, 600, and 800 °C) on the physicochemical properties of biochar produced from coffee husk, aiming at its use as a soil conditioner.

Results: The biomass was subjected to controlled pyrolysis in a muffle furnace at a heating rate of 5 °C.min⁻¹ and a residence time of one hour after reaching the final temperature. The resulting biochar was characterized for co-product yield, bulk density, chemical composition (ash, volatiles, and fixed carbon), and pH. Increasing the pyrolysis temperature reduced biochar yield and density, while increasing fixed carbon content. Fixed carbon increased from 67% at 400 °C to 77% at 800 °C, whereas volatile content decreased from 25% to 10%. The pH decreased up to 600 °C and increased at 800 °C.

Conclusions: Pyrolysis temperature strongly influences biochar properties, requiring a balance between yield and quality according to the intended application. Although all evaluated temperatures were technically feasible, biochar produced at 800 °C showed the greatest potential for long-term application in tropical acidic soils.

Keywords: Agro-industrial waste; Biomass; Sustainability; Coffee husks.

 

2- THINNING INTENSITY EFFECTS ON DIAMETER GROWTH DYNAMICS OF AFRICAN MAHOGANY STANDS

Andressa Ribeiro, Rafaella Carvalho Mayrinck, Ximena Mendes de Oliveira, Carolina Souza Jarochinski Dellú, Lara Reis Gualberto, Aimeé Jordania de Aquino Rocha, Maurício Martins Araújo, Antonio Carlos Ferraz Filho

Abstract

Background: African mahogany (Khaya spp.) is a valuable timber species that has gained increasing attention in Brazil due to its silvicultural advantages over Swietenia macrophylla, particularly its superior growth performance and resistance to native pests. Thinning is a key silvicultural practice, yet optimal timing and intensity remain unclear for African mahogany, as most commercial timber has historically been sourced from native forests. This study evaluated the effects of different thinning intensities on diameter growth over four years in two African mahogany stands in Brazil (established in 2013 and 2014) with an initial density of 333 trees ha⁻¹.

Results: In 2020, a randomized complete block design with three replications was implemented, applying light (308 trees ha⁻¹), moderate (258 trees ha⁻¹), and heavy (206 trees ha⁻¹) thinning treatments. The statistical analysis was restructured using a factorial arrangement. Results indicated a significant effect of stand age (p < 0.05), whereas thinning intensity and the interaction between factors were not significant (p > 0.05). Complementary analyses using aligned rank transform (ANOVA -ART) were conducted to assess temporal variation within each stand, indicating increased diameter growth over time. Linear regressions showed DBH growth across treatments, and diameter distributions, modeled using the Weibull 3P function, shifted toward larger classes, particularly under moderate and heavy thinning.

Conclusions: Stand age was the main factor influencing diameter growth, while thinning intensity showed no significant overall effect under the factorial approach. However, temporal analyses suggest that density reduction contributes to shifts toward larger diameter classes, supporting thinning as a relevant management practice in African mahogany plantations.

Keywords: forest management; Khaya grandifoliola; planted forest; silvicultural treatment; solid wood production.

 

3- A NEW CONTRIBUTION TO MULTICRITERIA ANALYSIS OF RURAL PROPERTY ELIGIBILITY FOR PAYMENTS FOR ECOSYSTEM SERVICES

Guilherme Ribeiro Aguiar, Luciano Cavalcante de Jesus França, Jussiara Dias dos Santos, Marcelino Santos de Morais, Reynaldo Campos Santana, Carolina Souza Jarochinski Dellú, Leomar Moreira Rodrigues, Huezer Viganô Sperandio, Carlos Vinicius Gonçalves Ribeiro, Danielle Piuzana Mucida

Abstract

Background: Payment for Ecosystem Services (PES) is a key instrument for conserving Ecosystem Services on rural properties. Implementing PES programs across large jurisdictions requires rigorous and transparent methods for selecting eligible areas. Multi-Criteria Decision Analysis (MCDA) integrated with Geographic Information Systems (GIS) is widely used for this purpose. However, MCDA faces challenges such as subjectivity in weight assignment, limited replicability, and underutilization of public geospatial data, such as the Rural Environmental Registry (CAR). Consequently, the literature lacks a robust framework combining MCDA transparency with optimized GIS procedures to generate objective eligibility indices. This study presents a methodological proposal to determine PES eligibility within sub-watersheds using MCDA.

Results: The highest eligibility levels were observed in properties with well-preserved areas, especially conserved Permanent Preservation Areas (PPA), high spring densities, and proximity to priority conservation zones, accounting for 4.83% of the total area. In contrast, the lowest eligibility occurred in regions dominated by intensive land use, pastures, and agriculture, with 26.7% and 17.19% classified as “Very Low” and “Low,” respectively. In total, 134 properties were analyzed, demonstrating diverse land-use patterns and distinct conservation contributions.

Conclusions: This research applied an MCDA-based methodology to CAR data to support property selection in PES programs. The model quantifies landowners’ role in protecting native vegetation to reduce deforestation pressure, while also identifying low-eligibility areas as targets for future ecological restoration. Although the study meets its core objective, the approach faces limitations related to the scale of geospatial data and the complexity of mapping cultural ES.

Keywords: Ecosystem services; environmental zoning; geographic information systems; rural environmental registry.

 

4-  HOW EDAPHIC AND HYDROLOGICAL CHARACTERISTICS DRIVE PLANT DISTRIBUTION PATTERNS: A STUDY OF FUNCTIONAL TRAITS IN SOUTHEASTERN BRAZIL FLOODPLAINS

Roberta Esteves Junqueira Bernardes, Tatiane Almeida Souza, Felipe de Carvalho Araújo, Fernanda Moreira Gianasi, Agatha Lopes Bazilio Ferreira, Ana Beatriz de Faria do Nascimento, Rafaella Tavares Pereira, Leony Aparecido Silva Ferreira, Miguel Gama Reis, Ana Lívia de Carvalho Rodrigues, André Maciel Silva-Sene, Fernanda de Oliveira, Lucélia Rodrigues Santos, Camila Laís Farrapo, Rubens Manoel dos Santos

Abstract

Background: Floodplains provide fertile soils and essential ecosystem services, including water purification and nutrient cycling, yet they are increasingly threatened by intense human pressure. This study investigated the diversity, structure, and functional traits of a tropical floodplain across five eco-units: Marginal Levee, Lower Terrace, Higher Terrace, Lower Plain, and Higher Plain.

Results: NMDS analysis demonstrated that species composition is strongly influenced by the flooding regime, with Inga vera dominant in most eco-units and Machaerium villosum prevailing in the Higher Plain. The Higher Plain exhibited the highest aboveground biomass (AGB) and structural heterogeneity. Diameter class distributions differed significantly among eco-units, while terraces showed a greater proportion of sprouting individuals, indicating adaptive responses to water stress. GLMM models revealed that species adopt conservative strategies under stressful conditions, producing thicker and more durable leaves, whereas stem density and specific stem density were associated with soil fertility.

Conclusions: Hydrological and edaphic factors play a central role in shaping community structure and functional strategies in tropical floodplain forests. These findings provide important insights for the conservation and management of floodplain ecosystems under increasing anthropogenic and climatic pressures.

Keywords: Community structure; ecological strategies; environmental filtering; hydrological gradients; inundated ecosystems.

 

5-  USE OF BIOCHAR IN WATER AND WASTEWATER TREATMENT: A BIBLIOMETRIC ANALYSIS AND STATE-OF-THE-ART REVIEW

Camila Juliana Sampaio Pereira, João Gilberto Meza Ucella Filho, Ariane Mateus de Souza, Angélica de Cassia Oliveira Carneiro, Emanoele Lima Abreu, Ana Marcia Macedo Ladeira Carvalho, Luis Henrique Cabral Barral, Antonio Machado Netto, Kezia Ellen Souza Bomfim, Renata Pereira Lopes Moreira, João Victor da Costa Santos

Abstract

Background: Biochar has emerged as a sustainable and efficient alternative for water and wastewater treatment due to its high surface area, porosity, chemical stability, and adsorption capacity. Over time, numerous studies have proposed methods for removing contaminants from water and wastewater to enable their reuse in accordance with Sustainable Development Goals (SDGs) 6 and 14. Among the techniques reported as effective in this context is the use of biochar. Therefore, the aim of the present study was to examine the state of the art and current trends regarding the use of biochar in water and wastewater treatment. To achieve this, a bibliometric analysis was conducted using the Scopus scientific database to identify the research landscape involving biochar for water and wastewater treatment.

Results: The use of residual agroforestry biomass for biochar production was predominant, including coffee husks, açaí seeds, bamboo, wood, rice husks, corn cobs, and forest residues. In addition, muffle furnaces were the most commonly used systems in thermal degradation processes. The pharmaceutical and textile industries, followed by water treatment facilities, were identified as the sectors with the greatest research interest involving biochar-based adsorbents.

Conclusions: Biochar demonstrated significant potential and efficiency for water and wastewater treatment due to its performance in removing contaminants such as pharmaceutical compounds, dyes, heavy metals, and emerging micropollutants. The successful removal of pollutants was mainly attributed to the adsorption mechanism associated with biochar, with improved performance observed after chemical activation. Therefore, biochar stands out not only as an adsorbent material, but also as a technology aligned with environmental remediation strategies, waste valorization, and sustainable water resource management.

Keywords: activated biochar; waste management; adsorption processes; wastewater treatment

 

6-  INSIGHTS INTO GROWTH PERFORMANCE AND WOOD QUALITY OF JUVENILE Corymbia SPP. FOR METALLURGICAL CHARCOAL PRODUCTION

Sofia Maria Gonçalves Rocha, Caio Varonill de Almada Oliveira, Thayanne Caroline Castor Neto, Stéffany de Lima Araujo, Graziela Baptista Vidaurre

Abstract

Background: The steel industry demands raw materials capable of improving charcoal quality and production efficiency. The objective of the study was to identify and quantify the potential advantages of Corymbia wood for charcoal production compared with Eucalyptus and to evaluate the influence of dendrometric, wood and charcoal properties on the differentiation of these genetic materials.

Results: The Corymbia hybrids exhibited lower height growth than Eucalyptus, while presenting wood that was, on average, 20% denser and contained 44% less heartwood. The resulting charcoal showed, on average, 2% higher gravimetric yield, 15% higher density, and 8% greater mechanical resistance than Eucalyptus charcoal. Basic density was identified as the variable most strongly associated with the differentiation among the evaluated genera and hybrids of C. torelliana x C. citriodora.

Conclusions: Although Corymbia hybrids showed lower growth, they produced a charcoal mass per hectare similar to that of E. urophylla x E. grandis. These results indicate the potential of the evaluated Corymbia hybrids as an alternative source of raw material for steelmaking charcoal production.

Keywords: Basic density; bioenergy; carbonization; mechanical resistance; steelmaking charcoal

 

7-  DEPENDENCE BETWEEN LIANAS AND TREE HEALTH IN MINAS GERAIS: RIDGE-PENALIZED LOGISTIC AND MULTINOMIAL COPULA MODELS

Isadora Azevedo Perpétuo, Marcelo Vitor Gualberto Santos Chaves, Elias Manensa Sabe, Rafael Genaro, Marcelo Ângelo Cirillo, Samuel José Silva Soares da Rocha, Luis Marcelo Tavares de Carvalho

Abstract

Background: This study presents an integrated statistical framework for the joint modeling of mixed ecological variables, simultaneously addressing issues of multicollinearity and dependence between response variables. Data from the National Forest Inventory of Minas Gerais were used to model liana presence (LP_bin), a binary variable, and tree health status (TH), an ordinal categorical variable with four levels.

Results: The marginal distribution of LP_bin was fitted using logistic regression with the penalized AURPLCE estimator, which showed satisfactory predictive performance (AUC = 0.771). For the TH variable, multinomial logistic regression was applied, and an additional ordinal regression analysis including LP_bin as a predictor of TH was also performed. Dependence between the responses was modeled using copulas, with the Clayton copula selected based on the Akaike Information Criterion (AIC = −72.0142). Estimates of Kendall’s coefficient (τ = 0.1109) and Spearman’s rank correlation (ρₛ = 0.1707) indicated a positive but weak dependence. The joint structure, represented by a probability table and heat map, revealed co-occurrence patterns, highlighting a higher probability of healthy trees in the absence of lianas (estimated probability of 0.3655).

Conclusions: Overall, the results underscore the potential of combining penalized estimators and copula-based models for the robust analysis of forest data, providing relevant quantitative insights into the relationship between liana presence and tree phytosanitary condition.

Keywords: Joint modeling; multicollinearity; ecological analyses; forest health

 

8-  HYDROLOGICAL IMPACT OF PINE SPECIES AND PLANTATION AGE IN THE SEMI-ARID MIXTECA ALTA, OAXACA

Adán Hernández-Hernández, Martin Enrique Romero-Sánchez, Antonio Gonzalez-Hernandez, Juan Francisco Castellano Bolaños, Feliciana Martínez-Aranda, Nancy Garcia-Asunción, Bertario Sánchez-Rosales

Abstract

Background: Rainfall redistribution by forest canopies is a key hydrological process influencing water availability in semi-arid ecosystems. However, information remains limited on how pine species and stand development affect rainfall partitioning in reforested landscapes of the Mixteca Alta region of Oaxaca, Mexico. This study evaluated throughfall, stemflow, and interception in Pinus pseudostrobus and Pinus greggii plantations ranging from 6 to 56 years old.

Results: Rainfall partitioning was monitored throughout the rainy season using throughfall collectors and stemflow collars installed in seven pine plantations. Throughfall generally decreased with stand age, whereas interception increased as canopy development progressed. Pinus pseudostrobus consistently allowed greater throughfall and exhibited lower interception losses than P. greggii, particularly in younger stands. In contrast, P. greggii showed greater canopy retention of rainfall, reflecting differences in canopy structure and density. Stemflow contributed only a small proportion of total precipitation and declined with increasing stand age in both species. Log-linear models indicated significant relationships between incident precipitation and rainfall redistribution components, while structural attributes such as crown diameter and basal area were associated with observed hydrological responses.

Conclusions: Species identity and stand age significantly influenced rainfall partitioning in semi-arid pine plantations. The greater interception observed in older stands and in P. greggii highlights the importance of canopy structure in regulating water inputs to the forest floor. These findings provide useful guidance for species selection and reforestation planning aimed at sustaining hydrological ecosystem services in water-limited environments

Keywords:JCanopy structure; Rainfall interception; Restoration hydrology; Stemflow; Throughfall.

9-  EVALUATION OF Araucaria angustifolia (BERTOL.) KUNTZE WOOD FOR ACOUSTIC GUITAR PRODUCTION AND MUSICAL ACCEPTANCE OF THE INSTRUMENT

Polliana D’Angelo Rios, Leonardo Seibett Kuhn, Natalia Durigon Melo, Luana Muller Souza, Rafaela Stange, Camila Alves Corrêa, Tarcisio Francisco de Camargo, Alexsandro Bayestorff da Cunha, Martha Andrea Brand, Rodrigo Figueredo Terezo, Paulo Henrique Mareze.

Abstract

Background: The acoustic quality of a guitar is directly influenced by the wood species used in its construction. Brazil has a diverse range of tree species with potential for lutherie, which could reduce production costs and encourage sustainable cultivation. In this context, this study evaluated the suitability of Araucaria angustifolia, a native species from southern Brazil, for use in guitar manufacturing. Acoustic, anatomical, chemical, physical, and mechanical properties of wood samples from three trees were analyzed, followed by the construction and evaluation of a guitar prototype.

Results: The results demonstrated promising acoustic performance, with a sound velocity of 4657 m·s⁻¹, a fundamental frequency of 199.1 Hz, and a logarithmic decay of 0.019 s. The wood showed suitability for use in the soundboard and back of the guitar. Significant correlations were observed between acoustic and mechanical properties and anatomical and chemical characteristics, including bordered pit diameter, solubility in ethanol and water, basic density, and tangential hardness. The wood exhibited a density of 430 kg·m⁻³ and lower shrinkage values compared with conventional tonewoods. Mechanical behavior was consistent with low-density woods, with an elastic modulus of 10,469 MPa. Evaluations conducted by professional musicians classified the instrument’s tonal quality as “Good” or “Very Good”.

Conclusions: The findings indicate that Araucaria angustifolia has significant potential for guitar manufacturing, especially in applications requiring lightweight tonewoods with favorable acoustic performance. The species represents a promising alternative for lutherie, contributing to the diversification of raw materials and the valorization of native Brazilian woods.

Keywords: Araucaria, technological characterization, string instrument.

 

10-  CLONAL SELECTION AND GENOTYPE-BY-ENVIRONMENT INTERACTION IN Eucalyptus FOR SUSTAINABLE FORESTRY IN ALAGOAS

Tulio dos Santos Nunes, Daniele Aparecida Alvarenga Arriel, Flávia Sampaio Alexandre, Rafael Ferreira Alfenas, Lúcio Mauro da Silva Guimarães, Davi Mesquita de Macedo, Acelino Couto Alfenas

Abstract

Background: The expansion of clonal eucalypts forestry into new forest frontiers in Northeastern Brazil requires selecting genotypes adapted to local conditions, thereby reducing pressure on native biomes such as the Caatinga. This study evaluated genotype-by-environment (G×E) interaction across four sites in Alagoas State based on mean annual increment (MAI) and survival (SUR) using 40 clones. The REML/BLUP, HMRPGV, and GGE biplot methodologies were applied, and following the analyses, an empirical index combining MAI and survival rate was employed for clone selection.

Results: A significant G×E interaction was detected, enabling the identification of two breeding zones and two mega-environments. Clones with high productive potential were selected. The HMRPGV method resulted in the highest genetic gain, while adjusting MAI by survival rate reshaped clone ranking and selection outcomes.

Conclusions: These findings provide robust recommendations for Alagoas, fostering efficient land use, reducing pressure on the Caatinga biome, and supporting the sustainable expansion of the regional forest base.

Keywords: Forest improvement; GGE biplot; REML/BLUP; Silviculture