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Background: This study presented a non-linear model to biologically describe the decomposition pattern, mass loss and nutrient release of four leaf litter species: Khaya senegalensis (African mahogany), Mangifera indica (Mango), Gmelina arborea (Beechwood), Eucalyptus camaldulensis (River red gum) and a mixture of the leaf litters using the standard litter bag technique. Objective: To explore different mathematical decomposition decay models in evaluating the decomposition rate and the relationship between mass loss and chemical parameters of some selected trees in Nigeria's northern Guinea savannah. Methodology: The experiment was a Completely Randomized Design with three replications. Fifteen litter bags were randomly placed in the field and retrieved at intervals of 0, 14, 28, 42, 56, 84, and 112 days (16 weeks). Three non-linear models were used to estimate the decomposition rate of the litter. Pearson correlation analysis was used to determine the relationship between mass loss and chemical composition. Results: Decomposition pattern gradually increased from 7 % up to 78.5 % by week 0 to 16 weeks. The leaf litter of Mangifera indica had the highest mass loss (62.9 %), followed by the litter mixture (44.0 %), Eucalyptus camaldulensis (43.6 %), Gmelina arborea (40.5 %) and Khaya senegalensis (39.3 %). Single exponential model (Adj R2=93.25-98.59%), double exponential model (Adj R2=87.93-98.98%), and three parameters asymptotic negative exponential model (Adj R2=93.82-98.84%), described the decomposition process efficiently. Correlation analysis of mass loss and chemical composition was highly significant (p ≤ 0.05), among all the leaf litter chemical properties, organic carbon, phosphorus, and nitrogen were the restraining factors. Implication: The mass loss was closely linked to the chemical properties of all the litter types. Among these properties, organic carbon and phosphorus were the limiting factors. Conclusion: We conclude that the single-leaf litter of Mangifera indica and Khaya senegalensis were superior in chemical composition, and decomposition than the mixed-leaf litter therefore they have the potential to enhancing soil fertility in the study area.

After forest suppression in mining areas, deterioration of stocked tropical hardwoods occurs at different rates and levels. Prioritizing logs to avoid wastage is challenging because the wide interspecific variability of wood traits makes natural resistance unpredictable. This work aimed to compare the biodeterioration of four Amazonian hardwoods from a mining stockyard to arboreal termite attacks over six weeks under laboratory conditions. The woods' chemical composition, anatomy, basic density, and crystallinity were determined. Mass loss and visual diagnosis of the specimens supported the biodegradability analyses. The species showed a wide range of mass loss after six weeks: Jacaranda copaia (pará-pará) - 15,2 %; Pseudopiptadenia suaveolens (timborana) - 0,8 %; Aegiphila integrifolia (tamanqueira) - 5,2 %; and Euxylophora paraensis (pau amarelo) - 0,5 %. Biodegradation did not stabilize over time for the lowest-density species. The crystallinity indicated the initial degradation of amorphous wood components, followed by a non-selective feeding mechanism. Gathering all species, increased extractive and lignin levels, fiber wall thickness, and basic density favored the natural wood resistance, oppositely to large vessel elements. The much lower basic density of J. copaia explains its lowest natural resistance. Wall thickness, pore diameter, and density overcame chemical composition on wood biodegradability. Low-density hardwoods stocked in mining yards are a priority for proper destinations.

In recent years, Colombia has seen an increase in the demand for peach fruits, but despite having adequate areas for peach production, neither production nor quality has increased because these fruits have a short post-harvest life and low firmness, which makes them susceptible to manipulation. The nutritional element Silicon affects the quality of these fruits when applied in fertilization, increasing firmness values, improving color, and favoring the concentration of metabolites. Therefore, the objective was to evaluate the edaphic application of different doses of silicon in the postharvest behavior of 'Dorado' peach fruits to maintain quality during storage for a longer time. A completely randomized block design with two blocks (stratum 1 and stratum 2) and five treatments (0, 300, 600, 900, or 120 kg ha-1 of silicon) was evaluated. The fruits from plants fertilized with 1200 kg ha-1 of Si showed more firmness and total soluble solids (TSS); however, the application of Si did not affect the other parameters. Fruits from stratum 1 had higher firmness and TSS than those from stratum 2, while the total carotenoids were not affected by stratum. The total titratable acidity and luminosity of the fruits decreased during postharvest, while the TSS only showed a slight increase. The respiratory rate presented the highest value ​​at 11 days of storage.

Fungi are the main decomposers of lignocellulose in temperate forests, and are classified as either white- or brown-rot, based on the ability to degrade lignin along with cellulose and hemicellulose. In this work, decomposition of Nothofagus pumilio wood by different wood-inhabiting fungal species was investigated through in vitro assays. Sapwood and heartwood blocks were individually exposed to 11 fungal species; mass loss was determined after 75, 135, and 195 days of exposure, comparatively analyzing the fungal ability to colonize and degrade this lignocellulosic substrate corresponding to both parts of the wood. Transverse section slices of the blocks were cut and separately stained with two types of dyes, Congo red and phloroglucinol, that are specifically associated with cellulose and lignin, respectively. Most of the species showed a different performance in sapwood and heartwood. Rhizochaete brunnea, Aurantiporus albidus and Phanerochaete velutina produced the greatest mass losses in sapwood. The latter two and Laetiporus portentosus produced the highest mass losses in heartwood, whereas Rh. brunnea was among the worst decomposers of this substrate. White rotters generally showed a higher ability to degrade the sapwood and brown rotters the heartwood. The fungal species that produced greater mass losses in heartwood than in sapwood grow on heartwood of living trees. Among white-rot fungi, two modes of action were identified: a) localized degradation, with zones of advanced decay in a less deteriorated matrix, and b) homogeneous degradation, with an even decay. Our results showed that many species have different performances in different substrates, reinforcing the importance of analyzing sapwood and heartwood decomposition separately, usually not done in this kind of studies.

This study aimed to investigate the effect of thermal modification and nano-zinc oxide (nano-ZnO) particle impregnation on the deterioration of Caribbean pine wood under field conditions. Samples were thermally-modified at various temperature levels (control, 180 °C, 200 °C, and 220 °C). Nano-ZnO impregnation was done with an aqueous solution at 1,5 % in an autoclave under two-steps of pressure and vacuum. Unmodified and thermally-modified, non-impregnated and nano-ZnO-impregnated samples were exposed to deterioration for five months in field tests. A deterioration index was used to evaluate the health condition of the samples. The mass loss and occurrence of termite tunnels in percentage were also determined. The nano-ZnO impregnation improved the resistance of unmodified wood to field-deterioration. The thermal modification at 180oC and 200ºC increased the wood deterioration and nano-ZnO impregnation did not improve their resistance. Unmodified and 220 ºC-modified samples had lower mass loss by xylophages than other thermal treatments regardless of the nanoparticle impregnation. The nano-ZnO impregnation decreases the occurrence of termite tunnels in unmodified, 200 ºC and 220 ºC-modified samples.

Thermal treatments have the effect of reducing the hygroscopicity and improving the resistance to microbiological attack of wood by the degradation of its chemical constituents. During the treatments, the mass of the wood is reduced, a factor that can affect the quality of the materials according to their use. The objective was to verify the effect of the thermal treatment variables on the thermogravimetric properties and the chemical composition of Eucalyptus grandis. The treatments were carried out in a vacuum oven with three atmosphere conditions - vacuum; N2; vacuum+N2 at temperatures of 140, 180 and 220 °C for 6 hours. It was observed that the mass loss during treatments differed only according to the temperatures used. The extractive content, total lignin and holocellulose presented significant changes only at 220°C in all three atmospheres. In the thermogravimetric analysis, the greatest value of residual mass was found in the treatment that used nitrogen and 220 °C, thus demonstrating that this treatment was more invasive, leading to the conclusion that the vacuum application can help to reduce the degradation of the constituents of the eucalypti wood. wood, which can lead to the production of thermally treated wood without great losses in the mechanical properties.

La producción de frutilla en Paraguay es realizada por pequeños productores, usando escasa tecnología y obtención de baja productividad, con la necesidad de ampliar los genotipos y la tecnología utilizada. El objetivo de esta investigación fue evaluar la calidad de frutos de genotipos de frutilla en función a la vernalización. El diseño utilizado fue el de bloques completos al azar con arreglo factorial 14x2. Los factores estuvieron constituidos por los genotipos y la vernalización con 15 plantas por tratamiento y tres repeticiones. Las mudas fueron mantenidas en cámara fría a 5°C, con 8 horas luz artificial y 16 de oscuridad por un periodo de 25 días. Se utilizaron cinco frutos por tratamiento y fueron evaluadas la cantidad de sólidos solubles totales, acidez titulable, relación de sólidos solubles totales con acidez titulable, relación longitud/diámetro, relación: diámetro del cáliz/diámetro del fruto, longitud del pedúnculo y pérdida de masa en postcosecha. Los datos obtenidos fueron sometidos a análisis de varianza en esquema factorial simple y las medias comparadas por el test de Tukey al 5% de probabilidad de error. La vernalización de las mudas no afectó la forma de los frutos de frutilla ni el contenido de sólidos solubles totales, pero aumentó el porcentaje de ácido cítrico. Así mismo, aumentaron la longitud del pedúnculo de la planta y la extensión del cáliz del fruto. Por otro lado, la vernalización disminuyó la pérdida postcosecha de masa fresca, pero no afectó la conservación de frutos a 5ºC. Los genotipos Festival y Florida Eliane pueden ser recomendados para consumo in natura y los genotipos Dover y Oso Grande para industria.

Ground contact speeds up timber decay because of the large number of microorganisms in soil. This study, we assessed the natural durability of seven tropical species using the European standard EN 807 (2001). We embedded samples of Dalbergia granadillo, Cordia elaeagnoides, Swietenia humillis, Tabebuia donell-smithii, Hura polyandra, Enterolobium cyclocarpum and Tabebuia rosea and temperate species Fagus sylvatica (as a control) in sandy, clay-sandy-loam and clay-loam for 8, 16, 24 and 32 weeks. We evaluated durability of the samples by determining the mass loss and modulus of elasticity (MOE) loss. The results varied significantly (p < 0.001) depending on timber species and soil type considered. The D. granadillo and C. elaeagnoides were the most durable, with mass losses of 4.5%, 6.5% and MOE losses of 4.5%, 20.5%, respectively. F. sylvatica, T. rosea and E. cyclocarpum samples were the least durable, with mass losses of 22.3-25% and MOE losses of 35.8-59.8%, respectively. Decay was most aggressive in sandy-clay-loam soil followed by the clay-loam soil and finally the sandy soil.

Knowledge of the respiration rate during the storage is important in the evaluation of the post-harvest tools that preserve fruit quality, and also for the provision of information for the development of new packages. This work aimed to evaluate the respiration rate of 'Golden' Carica papaya stored under refrigeration and controlled atmosphere conditions. The fruit was kept at 13 °C in controlled atmospheres comprising three levels of O2 (20.8 %, 6 %, 3 %) with a minimum level of CO2 (0.1 %); and three levels of CO2 (0.1 %, 6 %, 12 %) with the lowest level of O2 (3 %). Measurements were taken at intervals of 5 days during the 30 days of storage. The mass loss and the peel color of the fruits were identified at the end of the storage period. The fruit maintained under 'normal' atmosphere conditions (20.8 % O2 and 0.1 % CO2) increased its respiration rate after the 10th day, reaching after 30 days 4.3 times the initial value. After 30 days in 3 % O2, the respiration rate was 2.9 times less than in the normal atmosphere. The decrease in respiration rate minimized the mass loss in fruit stored at 3 % O2, but it was unaffected by increasing levels of CO2.

Objetivou-se com este trabalho avaliar a qualidade da maçã 'Maxi Gala' submetida a diferentes combinações de níveis de O2 e CO2, temperaturas e perda de massa durante o armazenamento. O experimento foi conduzido em um delineamento inteiramente casualisado em esquema de parcelas subdivididas, com quatro repetições de 25 frutos. Os tratamentos originaram-se da combinação de diferentes condições de atmosfera controlada (AC) em duas temperaturas (0,5 ºC e 1 ºC), que foram: (1) 1,2 kPa O2 + 2,5 kPa CO2 + 3,5% de perda de massa (PM); (2) 1,2 kPa O2 + 2,5 kPa CO2; (3) 1,2 kPa O2 + 2,0 kPa CO2; (4) 1,0 kPa O2 + 2,0 kPa CO2; (5) 0,8 kPa O2 + 2,0 kPa CO2; e (6) 0,8 kPa O2 + 1,5 kPa CO2. As melhores condições para o armazenamento da maçã 'Maxi Gala' foram as pressões parciais 0,8 a 1,0 kPa O2 associada com 2,0 kPa CO2 ou 0,8 kPa O2 com 1,5 kPa CO2 na temperatura de 1 ºC. Nessas condições ocorre maior manutenção da firmeza da polpa, redução na ocorrência de degenerescência senescente e a polpa farinácea. A perda de massa de 3,5% em AC com 1,2 kPa O2 + 2,5 kPa CO2 na temperatura de 1 ºC também é eficiente na manutenção da qualidade desta maçã.The objective of this study was to assess the quality of the 'Maxi Gala' apple under different mixtures of O2 and CO2, temperature and mass loss during storage. The experiment was carried out in a completely randomised design in a system of split-plots, with four replications of 25 fruits. The treatments, derived from the combination of various conditions of controlled atmosphere (CA) at two temperatures (0.5 ºC and 1 ºC), were: (1) 1.2 kPa O2 + 2.5 kPa CO2 + 3.5% mass loss (ML); (2) 1.2 kPa O2 + 2.5 kPa CO2; (3) 1.2 kPa O2 + 2.0 kPa CO2; (4) 1.0 kPa O2 + 2.0 kPa CO2; (5) 0.8 kPa O2 + 2.0 kPa CO2; and (6) 0.8 kPa O2 + 1.5 kPa CO2. The best conditions for the storage of the 'Maxi Gala' apple were those with partial pressures of 0.8 to 1.0 kPa O2 associated with 2.0 kPa CO2 or 0.8 kPa O2 with 1.5 kPa CO2 at a temperature of 1ºC. Under these conditions flesh firmness is maintained for longer, with a greater reduction in flesh breakdown and mealiness. A weight loss of 3.5% in CA with 1.2 kPa O2 to 2.5 kPa CO2 at a temperature of 1ºC is also effective in maintaining the quality of this apple.

The study investigated the effects of short-term thermo-mechanical (STTM) densification temperature and pressure on changes in surface wettability of alder (Alnus glutinosa), beech (Fagus sylvatica), birch (Betula verrucosa) and pine (Pinus sylvestris) wood veneer. Veneer sheets were densified using pressure levels of 4 MPa, 8 MPa and 12 MPa at three temperatures: 100°C, 150°C and 200°C for a short time of 4 min. Wettability was determined by measuring contact angles with distilled water. The results were compared with those of non-densified veneers. The results showed that in a relatively short process time wettability can be changed significantly. The wettability analysis showed that STTM-densified veneer surfaces became more hydrophobic, which indicates poor wettability. However, it was found that even STTM densification of veneers provides stable properties; in particular, contact angle values were stable for 24 hours after densification, which is an important consideration for industrial applications. The effect of temperature on the contact angle was more evident than that of pressure. Linear correlations were found between contact angle and both mass loss and compression ratio for all investigated wood species. These findings may be used to provide initial data for adhesive/ coating application processes in woodworking industry.

Heat treatment of Oriental-beech (Fagus orientalis) wood was carried out by hot air in an oven for 2, 4, and 8 h at 140, 170, and 200°C. After heat treatment, some physical characteristics such as surface roughness, color, glossiness, and mass loss of Oriental-beech wood specimens were measured. Our results showed that heat treatment caused decrease in surface roughness, glossiness, and mass loss values of Oriental-beech (Fagus orientalis) wood specimens. The decrease in lightness at all temperatures indicates that the specimens become darker with the treatment time. While, a* coordinate (red component) decreased as temperature increased, b* coordinate (yellow component) initially increased at 140°C and then decreased at 170°C and 200°C.