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Teak (Tectona grandis L.f.) plantations have increased recently in India; however, morphological descriptors for teak are still lacking. Thus, the goal of this work was to develop descriptors based on morphological characteristics. Among 30 seed sources collected from different states of India, 24 morphological descriptors, including leaf length, leaf width, presence of petiole, petiole length, leaf shape, shape of leaf apex, shape of leaf base, leaf texture, phyllotaxy, leaf attitude, leaf margin, leaf margin undulation, leaf brightness, leaf venation, leaf main vein, leaf veins, leaf vein color, leaf color, leaf pubescence, young leaf color, number of internodes, internodal length, trunk spots, and trunk color, were developed based on leaf and stem characteristics. These seed sources exhibited a difference in all traits except leaf shape, shape of leaf apex, leaf phyllotaxy, leaf margin, leaf venation, leaf main vein, and presence of trunk spots. The Jaccard similarity index was used to calculate the genetic similarity between the sources, and the Unweighted Pair Group Method with Arithmetic Mean (UPGMA) method was used to perform a cluster analysis (four groups at a similarity of 0.5 were obtained). According to the observations made, most of the sources exhibited high similarity, which indicates that only a few characteristics can be used to distinguish the sources.

High-value timber species play an important economic role in forest management. The individual tree information for such species is necessary for practical forest management and for conservation purposes. Digital aerial photogrammetry derived from an unmanned aerial vehicle (UAV-DAP) can provide fine spatial and spectral information, as well as information on the three-dimensional (3D) structure of a forest canopy. Light detection and ranging (LiDAR) data enable area-wide 3D tree mapping and provide accurate forest floor terrain information. In this study, we evaluated the potential use of UAV-DAP and LiDAR data for the estimation of individual tree location and diameter at breast height (DBH) values of large-size high-value timber species in northern Japanese mixed-wood forests. We performed multiresolution segmentation of UAV-DAP orthophotographs to derive individual tree crown. We used object-based image analysis and random forest algorithm to classify the forest canopy into five categories: three high-value timber species, other broadleaf species, and conifer species. The UAV-DAP technique produced overall accuracy values of 73% and 63% for classification of the forest canopy in two forest management sub-compartments. In addition, we estimated individual tree DBH Values of high-value timber species through field survey, LiDAR, and UAV-DAP data. The results indicated that UAV-DAP can predict individual tree DBH Values, with comparable accuracy to DBH prediction using field and LiDAR data. The results of this study are useful for forest managers when searching for high-value timber trees and estimating tree size in large mixed-wood forests and can be applied in single-tree management systems for high-value timber species.

IntroductionShorea macrophylla is a commercially important tropical tree species grown for timber and oil. It is amenable to plantation forestry due to its fast initial growth. Genomic selection (GS) has been used in tree breeding studies to shorten long breeding cycles but has not previously been applied to S. macrophylla .MethodsTo build genomic prediction models for GS, leaves and growth trait data were collected from a half-sib progeny population of S. macrophylla in Sari Bumi Kusuma forest concession, central Kalimantan, Indonesia. 18037 SNP markers were identified in two ddRAD-seq libraries. Genomic prediction models based on these SNPs were then generated for diameter at breast height and total height in the 7th year from planting (D7 and H7).Results and discussionThese traits were chosen because of their relatively high narrow-sense genomic heritability and because seven years was considered long enough to assess initial growth. Genomic prediction models were built using 6 methods and their derivatives with the full set of identified SNPs and subsets of 48, 96, and 192 SNPs selected based on the results of a genome-wide association study (GWAS). The GBLUP and RKHS methods gave the highest predictive ability for D7 and H7 with the sets of selected SNPs and showed that D7 has an additive genetic architecture while H7 has an epistatic genetic architecture. LightGBM and CNN1D also achieved high predictive abilities for D7 with 48 and 96 selected SNPs, and for H7 with 96 and 192 selected SNPs, showing that gradient boosting decision trees and deep learning can be useful in genomic prediction. Predictive abilities were higher in H7 when smaller number of SNP subsets selected by GWAS p -value was used, However, D7 showed the contrary tendency, which might have originated from the difference in genetic architecture between primary and secondary growth of the species. This study suggests that GS with GWAS-based SNP selection can be used in breeding for non-cultivated tree species to improve initial growth and reduce genotyping costs for next-generation seedlings.

Large areas of African moist forests are being logged in the context of supposedly sustainable management plans. It remains however controversial whether harvesting a few trees per hectare can be maintained in the long term while preserving other forest services as well. We used a unique 24 year silvicultural experiment, encompassing 10 4 ha plots established in the Central African Republic, to assess the effect of disturbance linked to logging (two to nine trees ha−1 greater than or equal to 80 cm DBH) and thinning (11–41 trees ha−1 greater than or equal to 50 cm DBH) on the structure and dynamics of the forest. Before silvicultural treatments, above-ground biomass (AGB) and timber stock (i.e. the volume of commercial trees greater than or equal to 80 cm DBH) in the plots amounted 374.5 ± 58.2 Mg ha−1 and 79.7 ± 45.9 m3 ha−1, respectively. We found that (i) natural control forest was increasing in AGB (2.58 ± 1.73 Mg dry mass ha−1 yr−1) and decreasing in timber stock (−0.33 ± 1.57 m3 ha−1 yr−1); (ii) the AGB recovered very quickly after logging and thinning, at a rate proportional to the disturbance intensity (mean recovery after 24 years: 144%). Compared with controls, the gain almost doubled in the logged plots (4.82 ± 1.22 Mg ha−1 yr−1) and tripled in the logged + thinned plots (8.03 ± 1.41 Mg ha−1 yr−1); (iii) the timber stock recovered slowly (mean recovery after 24 years: 41%), at a rate of 0.75 ± 0.51 m3 ha−1 yr−1 in the logged plots, and 0.81 ± 0.74 m3 ha−1 yr−1 in the logged + thinned plots. Although thinning significantly increased the gain in biomass, it had no effect on the gain in timber stock. However, thinning did foster the growth and survival of small- and medium-sized timber trees and should have a positive effect over the next felling cycle.

\"The present paper seeks to determine the volume and species of timber consumption in sawmill industries of Valley districts of Manipur State, India. The study finds a high growth rate of prices for all timber species. Species-wise data shows that about 60 percent of total inputs consumed by sawmill units are for furniture use and the rest for housing and construction. The study employs a log-linear multiple regression model to determine input consumption’s determinants. The regression analysis shows that units are not fully utilizing their installed capacity, as shown by the negative relationship between installed capacity and input consumption. Other factors like the area of the unit, capital investment, and perennial operation are factors that have positive impacts on the input consumption of the sawmill units.\"

Brazil is one of the largest producers of tropical wood in the world. Much of this wood is extracted from the Amazon region, especially in the state of Pará. Despite empirical knowledge, there is little information in the literature about the selectivity of trade and how this production has been behaving in recent years. Is there any relationship between this legal timber trade and deforestation? In this work, we compile data reports from control agencies and analyze the dynamics of the legal timber market in the state of Pará between 2009 and 2015 in terms of species, volume, and monetary value. We also correlate changes in volume m−3 and value m−3 with deforestation increase in the same period and region. We find that only ten groups of species represent almost 50% of the total timber volume marketed in the State, mainly from the Massaranduba (Manilkara) group. According to our models, the supply of a species of wood on the market is defined by its monetary value and not by its availability or characteristics, which hinders the insertion of new species and increases selectivity. Since 2011 the volume of legally traded logs has been decreasing sharply. Traditional forest regions in the state already demonstrate depletion in forested areas. While others, such as the lower Amazon region, have been increasing production, showing that new forestry operations areas are being used for harvesting in the function of the lower availability in traditional areas. Our models show that the legal reduced impact logging timber volume has an inverse relationship with the deforestation increase. Otherwise, preference for a small group of timber types still predominates, which may lead local woods to the danger of extinction.

Leguminosae is an economically important family that contains a large number of medicinal plants, many of which are widely used in African traditional medicine. Angola holds a great socio-cultural diversity and is one of the richest floristic regions of the world, with over 900 native Leguminosae species. This study is the first to assess the medicinal uses of the legumes in Angola and provides new data to promote the conservation and the sustainable use of these unique resources. We document the ethnobotanical knowledge on Angola by reviewing the most important herbarium collections and literature, complemented by recent field surveys. Our results revealed that 127 native legume species have medicinal uses and 65% of them have other important uses by local populations. The species with most medicinal applications are Erythrina abyssinica, Bauhinia thonningii and Pterocarpus angolensis . The rich flora found in Angola suggests an enormous potential for discovery of new drugs with therapeutic value. However, the overexploitation and the indiscriminate collection of legumes for multiple uses such as forage, food, timber and medical uses, increases the threats upon the native vegetation. Efforts to assess the conservation status of these species are urgently needed, and future actions should promote the sustainable use of medicinal plants in Angola together with the implementation of conservation strategies.

Temporal and spatial patterns in flowering phenology were assessed for eight tropical African tree species. Specifically, the frequency and seasonality of flowering at seven sites in central Africa were determined using field data, graphical analysis and circular statistics. Additionally, spatial variation in the timing of flowering across species range was investigated using herbarium data, analysing the relative influence of latitude, longitude and timing of the dry season with a Bayesian circular generalized linear model. Annual flowering was found for 20 out of the 25 populations studied. For 21 populations located at the north of the climatic hinge flowering was occurring during the dry season. The analysis of herbarium collections revealed a significant shift in the timing of flowering with latitude for E. suaveolens, and with the timing of the dry season for M. excelsa (and to a lesser extent L. alata), with the coexistence of two flowering peaks near the equator where the distribution of monthly rainfall is bimodal. For the other species, none of latitude, longitude or timing of the dry season had an effect on the timing of flowering. Our study highlights the need to identify the drivers of the flowering phenology of economically important African tree species.

The potential of integrating acid acetic leaching and torrefaction processes was studied to create an enhanced solid biofuel from lignocellulosic biomass. The focus was on evaluating the impact of these combined methods on ash removal efficiency and the melting characteristics of the treated biomass. Two possible strategies were considered: implementing torrefaction first followed by leaching, or conducting leaching first followed by torrefaction. By incorporating both leaching and torrefaction treatments, regardless of order, a solid biofuel with improved properties was attained, especially in terms of higher heating value yield and ash melting temperature compared to individual treatment (either only torrefaction or only leaching). Depending on the sequencing of the leaching treatment, there was a reduction in ash yield from raw biomass ranging between 60% and 86%, while for torrefied biomass it was between 47% and 68%. Leaching treatment before torrefaction treatment was determined to be a more effective combination.

Recombination orchards facilitate superior tree genotypes crossings and improved seed production. In this study we aimed to a) investigate genetic parameters in a progeny test of Cordia trichotoma (Vell.) Arráb. ex Steud.; b) establish a clonal recombination orchard using grafting of the selected trees by genetic values; and c) carry out pollen collection and processing. A provenance and progeny test was conducted and evaluated at nine years of age for growth traits. Quantitative genetic parameters were estimated, and superior genotypes were selected and preserved through grafting. Grafted plants were monitored, and pollen collection techniques were tested. The best 10 ranked individuals reached up to 33 m3 ha-1 year-1 MAI yield, with gains up to 55%. The grafting success rate reached up to 70% and pollen management was effective. Forest breeding programs for timber species like C. trichotoma were optimized by refining grafting and controlled pollination methods, making genetic recombination viable.