Zambia Forestry College

Background. Tree bark is a chemically and anatomically heterogeneous component of woody biomass that is often treated as a low-value by-product despite containing structural polymers, suberin, tannins, phenolics, terpenoids and other extractives with potential applications in materials, chemicals, adhesives, pharmaceuticals and energy. Bark structure determines protection, storage, transport and defence, while anatomical organization can influence the distribution, accessibility and recovery of chemical fractions. Objective. This systematic review synthesizes evidence on bark anatomy, chemical composition, extractive variation, functional properties, processing approaches and value-added applications, with particular emphasis on linking bark structure and chemistry to practical valorisation pathways within a circular forest bioeconomy. Methods. The review follows the PRISMA 2020 reporting framework and examines literature published from 1980 to 2026 using multidisciplinary bibliographic databases and supplementary sources. Eligible evidence covers bark anatomy, chemistry, extractives, medicinal properties, industrial applications and sustainability. The review retains the detailed evidence synthesis and quantitative analyses developed in the source manuscript, while organizing their interpretation around a structure–chemistry–function–process–product framework. Results. The reviewed evidence demonstrates substantial interspecific and environmental variation in bark thickness, periderm and rhytidome development, phloem organization, fibres, sclereids and secretory structures. Major chemical groups include phenolics, tannins, flavonoids, terpenoids, alkaloids, lignans, suberin, waxes and other extractives. These characteristics are associated with medicinal, adhesive, material, chemical and energy applications. The synthesis further identifies extraction, fractionation, tannin-based adhesives, composites, structural materials, thermochemical conversion and integrated biorefinery systems as important valorisation pathways, while emphasizing the need to valorise post-extraction residues. Conclusions. Bark should be considered a heterogeneous forest-product feedstock rather than a uniform residue. Its anatomy, chemistry and functional properties provide the basis for selecting appropriate extraction, processing and product pathways. Future research should integrate standardized bark characterization with process mass balances, product performance testing, life-cycle assessment and techno-economic analysis to support commercially viable circular forest biorefineries.

Tree bark is a structurally complex and chemically diverse component of woody plants that performs essential protective, physiological, and defensive functions while serving as an important reservoir of bioactive compounds with considerable medicinal and industrial value. Despite growing interest in bark as a renewable forest resource, information on its anatomical characteristics, chemical composition, extractive diversity, and utilization remains fragmented across forestry, wood science, plant anatomy, phytochemistry, pharmacology, and industrial processing literature. Consequently, a comprehensive synthesis of the available evidence is required to improve understanding of bark diversity and support sustainable resource utilization. This study systematically reviewed and quantitatively synthesized published literature on bark anatomy, chemical composition, extractive variation, medicinal properties, industrial applications, and implications for sustainable forest management among forest tree species. The review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA 2020) guidelines. Literature published between January 1980 and June 2026 was retrieved from major bibliographic databases, institutional repositories, and selected grey literature sources. Following systematic screening and eligibility assessment, 574 studies were included in the qualitative synthesis, while 311 studies provided sufficient quantitative data for random-effects meta-analysis. Standardized mean differences (Hedges' g) were calculated, and heterogeneity among studies was evaluated using Cochran's Q statistic and the I² statistic. The findings revealed substantial interspecific variation in bark anatomical characteristics, including bark thickness, periderm development, secondary phloem organization, secretory structures, and rhytidome formation. Phenolic compounds, flavonoids, tannins, terpenoids, alkaloids, lignans, and suberin were the most frequently reported chemical groups, demonstrating significant variation among species and ecological regions. Meta-analysis showed consistently large and statistically significant pooled effect sizes for bark anatomical characteristics (g = 0.72–0.89), chemical constituents (g = 0.68–0.91), medicinal activities (g = 0.76–0.89), and industrial applications (g = 0.72–0.91) (all p < 0.001). Bark-derived compounds exhibited considerable antioxidant, antimicrobial, anti-inflammatory, anticancer, and antidiabetic potential, while industrial applications extended to pharmaceuticals, nutraceuticals, leather tanning, wood adhesives, cosmetics, biopolymers, environmental remediation, and renewable bioenergy production. The review demonstrates that tree bark represents an underutilized but strategically important forest resource capable of supporting sustainable forest-based bioeconomies through the recovery of high-value phytochemicals and efficient biomass utilization. Integrating knowledge of bark anatomy, chemistry, and extractive diversity into forest management and industrial processing can enhance resource-use efficiency, promote value addition, reduce processing waste, and strengthen the transition toward circular bioeconomy systems. Future research should prioritize standardized analytical methodologies, greater representation of under-investigated indigenous tree species, long-term sustainability assessments, and the commercialization of bark-derived products to maximize the ecological and socio-economic benefits of forest resources.

Forest plantations play a critical role in meeting demand for timber, poles, pulpwood, fuelwood and other forest products while reducing pressure on natural forests. In Zambia, plantation forestry is dominated by exotic species, particularly Pinus and Eucalyptus, but timber quality is influenced by silvicultural practices, site conditions, climate variability, pests, diseases and management interventions. This systematic review synthesizes evidence on silvicultural management, timber quality improvement and dendrochronological applications in Zambian forest plantations. Following the PRISMA 2020 framework, literature published between 1980 and 2026 was identified from Scopus, Web of Science, ScienceDirect, SpringerLink, Wiley Online Library, CAB Abstracts, Google Scholar and additional forestry and institutional sources. The review evaluates species–site matching, spacing, thinning, pruning, weed control, fertilization, fire management, pest and disease control, and the use of tree-ring analysis to understand growth dynamics, climate responses, wood formation and rotation-age decisions. A total of 1,624 records were identified, 1,310 were screened after duplicate removal, 382 full texts were assessed, and 142 studies met the inclusion criteria. Because of substantial heterogeneity among studies, thematic synthesis was used rather than quantitative meta-analysis. The evidence indicates that management interventions can influence stem form, diameter growth, knot development, wood density and timber value, while dendrochronology provides long-term information on growth patterns, climatic responses, disturbances and management effects. Integrating silvicultural management with tree-ring monitoring offers a practical framework for improving timber quality, growth modelling and climate-adaptive plantation management in Zambia.

This paper examines the methodological and ethical challenges of conducting remote research on child‐animal relationships across thirty communities in 17 countries during the COVID‐19 pandemic. It critically assesses remote research as a mode of collaboration informed by decolonial aspirations, highlighting the complexities of navigating temporal and geographical distances, mitigating global inequalities, and addressing political and methodological tensions at the intersection of psychological anthropology and cross‐cultural developmental psychology. By engaging with these challenges, the paper fosters critical dialogue on research ethics and methodologies between anthropology and psychology, advancing a broader intellectual engagement toward translocal equity.

In this study, Odontolabis taynguyensis Xin, Zhong & Qi, sp. nov., is described from central Vietnam based on morphological and mitochondrial COI gene evidence. The new species could be distinguished from related species by external characters. Phylogenetic analysis supports designating O. platynota coomani (Didier, 1927) as a junior synonym of O. p. platynota (Hope, 1845), as both genetic distance and tree topology demonstrate that O. p. coomani is nested within the O. p. platynota clade and lacks an independent lineage.