International Journal of Forestry Research

The availability of high-resolution satellite imagery has boosted the modelling of tropical forest attributes based on texture metrics derived from grey-level co-occurrence matrices (GLCMs). This procedure has shown that GLCM metrics are good predictors of vegetation attributes. Nonetheless, the procedure is also sensitive to the scale of analysis (image resolution and plot size). This study aimed to analyse the effect of spatial scale on the modelling of forest attributes, and to provide some ecological insight into such effect. Nineteen 32 × 32 m sampling plots were used to quantify forest structure (basal area: BA; mean height: H; standard deviation of height, HSD; density, D; and aboveground biomass, AGB). The 19 plots were subdivided into four 16 × 16 m, one of which was subdivided into four 8 × 8 m plots. To match this design, 12 GLCM metrics were calculated from a GeoEye-1 image (pixel size ≤ 2 m) using a 5-, 9-, and 21-pixel window from the R, NIR, NDVI, and EVI bands. For each of the windows, we modelled the five structural variables as linear combinations of the 12 metrics through linear models. The modelling potential ranged from high ( = 0.70) to low (0.11). H was the best-predicted attribute; this occurred at the smallest scale, with increasing scales producing lower values. The second best-predicted attribute was HSD, which peaked at the intermediate scale. D and AGB displayed a similar pattern. BA was the only attribute best predicted at the largest scale. Thus, in predicting tropical forest attributes from GLCM-derived texture metrics, the spatial scale to be used should reflect the spatial scale at which ecological processes occur. Therefore, understanding how ecological processes express themselves in a remotely sensed image becomes a critical task.

This study sought to assess the density and anatomical features of young and old Bambusa vulgaris Schrad. ex JC Wendl. culm heights and, therefore, evaluate their influence on the utilization potential of the culm as a sustainable structural material. Bambusa vulgaris culm of 2-year and 4-year-old were harvested and prepared to the required length of 6 meters for the study. Basic density and anatomical features were carried out. The results showed that the basic density of old bamboo ranges from 652.91 kg/m³ to 729.06 kg/m³, while the young bamboo ranges from 342.33 kg/m³ to 509.52 kg/m³. The vascular bundle arrangement was found to be in Type III and Type IV for the culm heights of both young and old bamboo. The average vascular bundle radial diameter ranged from 761.13 μm to 890.78 μm for the old culm and 727.16 μm to 844.83 μm for the young culm. The average vascular bundle tangential diameter ranged from 499.44 μm to 533.49 μm for the old culm and 425.56 μm to 483.56 μm for the young culm. The radial diameter of the metaxylem vessel of the old culm ranged from 216.81 μm to 54.74 μm, while 214.23 μm to 73.86 μm were for the young culm. Parenchyma tissues ranged from 35%– to 70% for the old bamboo culm and 45% to 75% for the young bamboo culm. Vessel proportion ranged from 6%–12% for the old culm while the young culm ranged from 5%–11%. Fiber proportion ranged from 22% to 54% for the old culm and 19% to 44% for the young culm. Old bamboo had better vascular bundle properties than that of young bamboo. The density is significantly correlated positively to the anatomical properties. Old bamboo is more suitable to be used as the engineered composite material due to its better anatomical features across the culm wall thickness.

Amburana cearensis (Fabaceae) is a native tree of the Brazilian northeastern semiarid region, which has considerable economic, medicinal, and social importance, especially in the Caatinga biome. This study aims to identify the scientific knowledge generated about the pharmacological applicability of the species. We analyzed scientific works on the widespread pharmacological use of A. cearensis, adopting the scientometric research method. The medicinal properties were classified according to the uses mentioned in the manuscripts, considering body systems and treated symptoms. They were associated with the International Classification of Diseases and Related Health. We identified a total of 86 articles addressing the medicinal potential of the species, distributed in 57 journals published between 2005 and 2023. There was a significant increase in publications during the period evaluated. Also, the species has been widely used in traditional medicine, which has attracted new studies, especially experimental ones focusing on unraveling its pharmacological potential. One trend observed was a significant geographic bias, since most of the studies investigated were carried out by researchers linked to Brazilian institutions located mainly in the northeast. This region includes the largest number of species occurrence points, explaining the interest of these institutions in recognizing the biological potential of their local or regional flora. In-depth investigations into the medicinal properties and secondary metabolites produced by A. cearensis should continue so that its therapeutic benefits are fully understood. However, it is necessary to link research into chemical and pharmacological properties with consideration of the importance of sustainable management of the species, since it faces risks of extinction. We acknowledge that an earlier version of this manuscript was presented as a dissertation by Ayane Emília Dantas dos Santos to fulfil the academic requirements for the degree of Forest Science at the Federal University of Rio Grande do Norte. The dissertation is available for reference at the following link: https://repositorio.ufrn.br/jspui/bitstream/123456789/46918/1/Cienciometriaetnobotanicamodelagem_Santos_2022.pdf.

Improved understanding of relationships among plant traits, stand characteristics, and soil properties can provide insights into the regenerating tree communities of commercial teak plantations. We investigated whether plant traits could be used to predict the natural regeneration of woody species in teak plantations with different soil and stand conditions. Data were collected in fifty 20 m × 20 m plots that were established in teak plantations of varying ages in northern Thailand. We analyzed differences in stand characteristics, soil properties, and community-level functional traits among sites. The RLQ analysis was performed to explore the associations among species abundances, plant traits, and a combined set of soil variables and stand characteristics. Our results showed that tree species with high leaf dry matter contents and high wood density dominated communities in an older teak plantation and were associated with high OM and N concentrations. Trees with larger leaves are increased in plantations that had experienced their first teak thinning, and were rich in organic matter. Species with high specific leaf areas increased in sites with high teak basal areas and which had experienced more intense thinning on fertile soils. Thick-leaved species had high importance values on sites with high densities of teak and infertile soils. Our results indicated that tree communities with similar conspecific traits were associated with specific soil and stand conditions in teak plantations. A knowledge of these regeneration dynamics may allow forest managers to encourage increased natural regeneration and enhanced diversity in commercial teak plantations.

The cashew tree relies heavily on the presence of pollinators during the peak receptivity of its flower to facilitate the transfer of pollen from the stamen to the stigma and ensure successful fruit production. Apis mellifera bees play a crucial role as intermediaries in the pollination process of the fruit, simultaneously extracting nectar and pollen from the flowers. The pollination service (PS) is susceptible to various risk factors that, if realized, could impact both the beekeeping industry and cashew production. This article aims to assess the operational risks associated with pollination service for Anacardium occidentale production in Vichada, Colombia, as a strategic measure to safeguard the business’s value. Drawing on expert opinions and relevant literature, nineteen risks were identified, encompassing threats such as fires, thefts, attacks by wild animals, unexpected rains, etc. Following the application of Failure Mode and Effects Analysis (FMEA), four risks were prioritized based on their severity and occurrence. Subsequently, Value at Risk (VaR) was employed for risk evaluation. The anticipated loss for the pollination service, resulting from these prioritized risks: 1, 9, 12 and 13, was quantified at $226674 ± $19096 per year for an 8000-hectare margin with a confidence level of 95%. The economic loss for 16000 hectares was $453348 ± $38192. This substantial value is of great significance to the beekeeping sector, translating to a loss of $27.3 per hectare per year and directly impacting the estimated $437824 loss in the cashew sector. Such losses have far-reaching consequences, affecting the livelihoods of peasant beekeepers in the region and potentially discouraging the maintenance of bee colonies and forests.

Empirical evidence on the patterns of the multipurpose trees distribution and regeneration status, which are under threats pressure is necessary for the proper management and conservation of the species. Prunus africana is listed as vulnerable while Albizia gummifera is listed as least concern amongst the multipurpose trees. This study was aimed to investigate the distribution, abundance, density, and regeneration status of Prunus africana and Albizia gummifera along agroecology and farmers’ wealth status in agroforestry. Stratification sampling and equal sampling techniques were employed. A total of 162 quadrats were laid within the randomly selected 54 households’ farms. A nested quadrat size was 20 m × 20 m for enset tree-based homegarden and parklands. For live fencing, a quadrat size was 4 m × 10 m. Abundance, diameter (cm), height (m), and growth habits of both trees were recorded. Density (stems per ha), diameter class (cm), height (m) class of both trees, and mean of growth habit were analyzed and considered. One-way ANOVA analysis and independent t-test were employed for means comparison by using SPSS V. 23.0. A total of 132 individual A. gummifera was recorded along agroecology while a total of 55 individual P. africana was recorded along agroecology. Mean density (stem/ha) of A. gummifera and P. africana showed significant difference between agroecology and farmers’ wealth groups (). A. gummifera and P. africana were sparsely distributed in the enset tree-based homegarden, parklands, and live fencing along agroecology. The overall diameter (cm) class and height (m) class distribution pattern of these tree species were observed as a J-shaped curve. The regeneration status of A. gummifera and P. africana was poor. In conclusion, distribution, abundance, and regeneration status of A. gummifera and P. africana were influenced by agroecology and farmers’ wealth status needing appropriate conservation measures.