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Root system mechanical reinforcement through root-soil cohesion on slope stability is important. However, the root cohesion of Tectona grandis, Maesopsis eminii, and shrubs (Chromolaena odorata) on slope stability is rarely studied and modelled. This study aimed to model the mechanical effect of vegetation through root cohesion, namely teak (Tectona grandis), Maesopsis eminii, and shrubs (Chromolaena odorata). The study was conducted in a simultaneous landslide on January 1, 2020, that dominantly occurred on vegetated slopes of Sukajaya District, Bogor Regency, West Java. The Wu model's root cohesion (CR) was modelled on slope stability using a modified Bishop model. The modelling used the data from field and laboratory-measured. The study found that the presence of a root system increases slope stability's factor of safety (FOS). The root system of young Maesopsiss eminii produces the largest effect of FOS compared to the root system of shrubs, teak, and old Maesopsis eminii. The slope stability of vegetated slopes is a function of the CR and the effective root zone depth. The highest total CR of vegetation was teak with 0.398 kPa, followed by shrubs, young Maesopsis eminii, and old Maesopsis eminii with 0.202 kPa, 0.191 kPa, and 0.087 kPa, respectively. The effective root zone of teak, young Maesopsis eminii, and shrub were 500, 230, 140, and 66 cm, respectively.

Boundary between core and outer wood should be clarified for tropical fast-growing tree species to utilize its wood resources under sustainable forestry. This study aimed to determine the boundary between core and outer wood based on the mixed-effects models for radial variations of anatomical characteristics and wood properties in three fast-growing tree species grown in community forests in Indonesia – Acacia mangium Willd., Maesopsis eminii Engl., and Melia azedarach L.. On the basis of the results of the radial variation modeling, almost all anatomical characteristics and wood properties were shown to increase or decrease from pith to bark and then become almost stable. The boundary values between core and outer wood based on exponential function with plateau for absolute changing ratios of estimated properties were 6.1, 6.8, and 5.5 cm for A. mangium, M. eminii, and M. azedarach, respectively. In conclusion, boundary between core and outer wood in respect to multiple characteristics and properties in tropical fast-growing tree species can be determined by combination of mixed-effects modeling and exponential function with convergence. [ABSTRACT FROM AUTHOR]

Plantations of tropical species are becoming an increasingly important source of wood. However, it is important that research trials focus not only on tree growth performance, but also on wood quality. The aims of this study were to assess the growth performance of six commercially and ecologically important tree species from separate plantation trials in Indonesia and to determine the relationships between tree growth and wood quality in terms of the dynamic modulus of elasticity (MOE) and wood density. Forty-eight 7-year Maesopsis eminii Engl. and thirty-five 9-year specimens (7 each of 5 Shorea spp.) were selected from two trials. The MOE, based on acoustic velocity, was indirectly measured to evaluate wood stiffness. Tree-growth performance was evaluated, and correlations between growth traits and acoustic velocity as well as density and wood stiffness properties were estimated. The growth performance of M. eminii in terms of tree volume was significantly different in three different categories of growth (i.e. fast, medium, slow). Of the five Shorea spp. studied, Shorea leprosula Miq. had the highest growth rate, as expected since it is known to be a fast-growing Shorea species. Indirect measurement of wood quality by means of non-destructive ultrasonic methods showed a weak negative correlation between tree volume and acoustic velocity and dynamic MOE. Although each fast-growing tree could reach a merchantable size faster than other varieties or species, wood traits of various species tested were not significantly different based on tree growth rate performance. The findings from this study could be used to improve selection criteria in future breeding trials; indirect measurements of the dynamic modulus of elasticity can be used in mass pre-selection of genetic materials, to choose the most-promising material for in-depth evaluation. [ABSTRACT FROM AUTHOR]

Photoassimilate distribution inside leaves is less studied than photosynthesis, and yet the topic is important as it gives insights into the vital roles played by leaves in plant survival. We combined greenhouse measurements of light response curves with 11C-labelling using leaves of 3-year-old potted Maesopsis eminii Engl. trees to improve our understanding of its leaf carbon physiology. This fast-growing pioneer tree species showed low photosynthetic rates for a common tropical pioneer during well-watered reference conditions (5.0 ± 0.7 µmol m-2 s-1), which further decreased in response to drought. 11C-autoradiography indicated active phloem loading and/or rapid phloem transport rates. Active loading is uncommon in tree species, but might be related to deciduousness traits and continuous investment in growth, like in herbaceous active loaders. Active loading involves higher carbon allocation to growth, which might explain why low photosynthetic rates were observed in this fast-growing species. These findings suggest that examining photoassimilate distribution and transport may be critical for understanding the role tree physiology plays in terrestrial carbon cycling. [ABSTRACT FROM AUTHOR]

Maesopsis eminii is referred to as one of the most widely distributed African tree species. However, its occurrence in Africa has never been mapped and little is known as to how this species can sustain in different environments. To gain insight into Maesopsis' ecology, we (i) made a synthesis of its functional trait data from the literature, (ii) investigated phenological patterns using data on four M. eminii trees from Yangambi, DR Congo, (iii) assessed an empirical provenance trial from Uganda on 600 Maesopsis trees and (iv) synthesized geo-referenced point location maps of Maesopsis entailing WorldClim precipitation and temperature and FAO soils, rainfall and ecological zones for Africa. We found M. eminii to straddle the equator equidistantly in terms of latitude (10.97°N and 10.98°S) covering five forest types where twenty soil types and variable rainfall regimes support complex plant biodiversity. Maesopsis eminii was, however, largely concentrated in the tropical rainforest ecosystem which contains fertile Orthic Ferralsol soils. More than 97% of the point locations were found where annual precipitation was >1000 mm, and 82% occurred where average annual temperature was 22-28°C. Its functional traits, phenology and provenance trial findings explained its occurrence in Africa. [ABSTRACT FROM AUTHOR]

The impact of drought on the hydraulic functioning of important African tree species, like Maesopsis eminii Engl., is poorly understood. To map the hydraulic response to drought-induced cavitation, sole reliance on the water potential at which 50% loss of xylem hydraulic conductivity (Ψ50) occurs might be limiting and at times misleading as the value alone does not give a comprehensive overview of strategies evoked by M. eminii to cope with drought. This article therefore uses a methodological framework to study the different aspects of drought-induced cavitation and water relations in M. eminii. Hydraulic functioning of wholebranch segments was investigated during bench-top dehydration. Cumulative acoustic emissions and continuous weight measurements were used to quantify M. eminii's vulnerability to drought-induced cavitation and hydraulic capacitance. Wood structural traits, including wood density, vessel area, diameter and wall thickness, vessel grouping index, solitary vessel index and vessel wall reinforcement, were used to underpin observed physiological responses. On average, M. eminii's Ψ50 (±SE) was -1.9 ± 0.1 MPa, portraying its xylem as drought vulnerable, just as one would expect for a common tropical pioneer. However, M. eminii additionally employed an interesting desiccation delay strategy, fuelled by internal relocation of leaf water, hydraulic capacitance and the presence of parenchyma around the xylem vessels. Our findings suggest that exclusive dependence on Ψ50 would have misdirected our assessments of M. eminii's drought stress vulnerability. Hydraulic capacitance linked to anatomy and leaf-water relocation behaviour was equally important to better understand M. eminii's drought survival strategies. Because our study was conducted on branches of 3-year-old greenhouse-grown M. eminii seedlings, the findings cannot be simply extrapolated to adult M. eminii trees or their mature wood, because structural and physiological plant properties change with age. The techniques and methodological framework used in this study are, however, transferable to other species regardless of age. [ABSTRACT FROM AUTHOR]

With increased drought events affecting forests globally, little is known about their future impact on Africa’s forests. In particular, we need to gain a better understanding of how key African forest species will respond to drought stress. In this study, we investigated functional traits and physiological responses to drought of the light-demanding pioneer species Maesopsis eminii Engl. The study involved an experiment on potted M. eminii seedlings with three different drought treatments in which sap flow (SF), stem diameter variation (SDV) and stomatal conductance (g s ) were measured. Whereas low g s rates (39 ± 30 mmol m −2 s −1 ) and pronounced SF-VPD (vapour pressure deficit) and g s -VPD hysteresis loops during well-watered conditions indicated conservative stomatal control on water loss, nocturnal sap flow implied M. eminii is not able to completely block transpiration. At the onset of drought, the pioneer seedlings retained high stem diameter growth despite highly reduced soil moisture (>−0.95 ± 0.03 MPa) and SF rates, indicating that growth was prioritised. Contribution of stored stem water to daily water use was limited both during drought and control conditions, which was confirmed by the absence of time lags between photosynthetic active radiation (PAR)-SDV, PAR-SF and SDV-SF in all treatments. Below a soil water potential of −0.95 ± 0.03 MPa, leaves were gradually shed, but diurnal and nocturnal SF did not turn zero, and absolute stem diameter kept decreasing for the entire experimental period (115 days), portraying that M. eminii seedlings can survive only limited drought periods. In sum, this study demonstrated that species-specific traits, as opposed to species ecological strategy, govern drought performance. For M. eminii , its leaf traits proved pivotal to its drought performance. [ABSTRACT FROM AUTHOR]

Maesopsis eminii is one of alien and invasive plant in Indoensia and planted in Resort Bodogol, Gunung Gede PangrangoNational Park. The results showed M. eminii has dorsiventral and hypostomatic leaf type with anomocytic stomata, drusse type ofCaCO3 crystal, multicellular and uniseriate trichomes in the upper and lower surface. While its stem has variation in its ray initiallayer depend on its trunk circumference.

Few studies have attempted to identify factors that contribute to aboveground carbon offset additionality in forest restoration planting in the tropics. Moreover, those that have compared aboveground carbon offset potential of naturally regenerating secondary forests and plantation forests have yielded conflicting results regarding the ability of the latter to attain carbon offset additionality, thus limiting broad adoption of carbon-driven forest restoration interventions. We assessed woody species diversity, stem density, stem diameter and wood specific gravity of secondary and plantation forests in Kakamega Forest in western Kenya to identify determinants of aboveground carbon offset additionality in plantation forests. Secondary forests comprised old-growth, middle-aged and young vegetation stands. Plantation forests consisted of mixed indigenous, Maesopsis eminii indigenous monoculture and Cupressus lusitanica , Pinus patula and Bischofia javanica exotic monoculture stands. Assessment was carried in 135 sample plots in three forest blocks using stratified systematic sampling in nested plots. Analysis of variance indicated that there was no significant difference in woody species diversity between secondary and plantation forests due to natural forest succession in both forest types. Mixed indigenous plantation had more aboveground carbon stock than secondary forest stands of comparable stand age due to its greater proportion of tree species with high wood specific gravity and large tree diameter. Old-growth secondary forest had more aboveground carbon stock than monoculture forest plantations due to its relatively higher wood specific gravity. Middle-aged secondary forest had relatively lower aboveground carbon stock than plantation forests of comparable stand age because of its smaller tree diameter. The results suggest that stem diameter and wood specific gravity are the most important determinants of aboveground carbon offset additionality. Thus, forest managers and investors in carbon offset projects can achieve aboveground carbon offset additionality in forest restoration interventions by planting tree species with relatively higher wood specific gravity and manipulating them to attain large stem diameter through silvicultural management. [ABSTRACT FROM AUTHOR]

The breeding season diet and nesting characteristics of the Silvery-cheeked HornbillBycanistes brevisare poorly known. To further understand these aspects of the breeding biology of this hornbill species, 14 nests were studied in and around Amani Nature Reserve located in the East Usambara Mountains, Tanzania. Nesting tree species were identified and the diet composition of nesting hornbills was evaluated between July and November 2001. The ejecta from each nest were collected, inventoried, identified (as completely as possible) and enumerated. Food items were categorised as plant, vertebrate or invertebrate. Plants, represented largely by fruits, were the dominant food type (n= 861), followed by invertebrates (n= 306; mainly millipedes and beetles), and vertebrates (n= 15; mainly smaller birds and chameleons). A comparison of results from the current study to other nesting observations made approximately seven decades earlier in the same area suggest that (1) the invasive tree speciesMaesopsis eminii, which was the most common food type consumed (n= 4 539 seeds), has become a favoured new food source in the breeding season, and (2) the breeding season appears to have shifted to an earlier period, potentially due to the fruiting phenology and abundance ofMaesopsis eminii. [ABSTRACT FROM AUTHOR]

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Estimates of above-ground biomass are required for better planning, sustainable management and monitoring of changes in carbon stocks in agroforestry systems. The objective of this study was to develop and compare biomass equations for Markhamia lutea, Casuarina equisetifolia, Maesopsis eminii and Grevillea robusta grown in a linear simultaneous agroforestry system in Uganda. These species were established in single rows in the middle of fields in 1995 from four-month old seedlings. A total of 57 trees were sampled for this study, 13 for M. lutea, 12 for C. equisetifolia, 16 for M. eminii and 16 for G. robusta. Biomass values of the various tree components (stem, branches and foliage) as well as the total above-ground biomass were fitted to linear and non-linear allometric models using total height, diameter-at-breast height (DBH), crown width as predictor variables. Although both DBH and height are typically used as independent variables for predicting above-ground biomass, the addition of height in biomass equations did not significantly improve model performance for M. eminii, M. lutea and G. robusta. However, addition of height significantly increased the proportion of variation explained in above-ground biomass for C. equisetifolia, while DBH did not significantly improve the prediction of biomass. The study confirmed the need for developing species-specific biomass equations. [ABSTRACT FROM AUTHOR]

The objective of this study was to quantify and compare the amount and distribution of soil organic carbon (SOC) under a linear simultaneous agroforestry system with different tree species treatments. Field work was conducted at Kifu National Forestry Resources Research Institute in Mukono District, Central Uganda, in a linear agroforestry system established in 1995 with four different tree species and a crop only control treatment. Soil samples were collected in 2006 at three depths; 0-25, 25-50, and 50-100 cm, before planting and after harvesting a maize crop. The results indicate that an agroforestry system has significant potential to increase SOC as compared to the crop only control. There was no significant difference in the amount of SOC under exotic and indigenous tree species. Among the exotic species, Grevillea robusta had higher SOC than Casuarina equisetifolia across the entire depth sampled. There is significant difference in SOC among the indigenous species, where Maesopsis eminii has more SOC than Markhamia lutea. Distance from the tree row did not significantly influence SOC concentration under any of the tree species. In selecting a tree species to integrate with crops that will sequester reasonable quantities of carbon as well as boost the performance of the crops, a farmer can either plant an exotic species or an indigenous. In this study, the soil under Grevillea robusta and Maesopsis eminii have the highest potential to store organic carbon compared to soil under other tree species. [ABSTRACT FROM AUTHOR]

Comparative studies on plant species richness, endemism, floristic composition, and structure between protected and unprotected forests are few in the Eastern Arc Mountains, one of the most biodiverse ecosystems in Africa. This study from one mountain range, the East Usambaras, examines floristic and structural tree data from 41-0.5 ha plots in four types of Eastern Arc forest: active agroforests, recently abandoned agroforests, mature secondary forest, and natural forest. Active agroforests had significantly lower tree species richness, endemic species richness, and stand density compared to natural and mature secondary forest. Recently abandoned agroforests contained a higher tree species richness, density, and tree height than active agroforests. Active and abandoned agroforests were dominated by an invasive tree, Maesopsis eminii. This tree species makes up a large percentage of the stems in active agroforests (26%), recently abandoned agroforests (32%), and in the canopy of mature secondary forests ∼ 30 years post logging (30%). Through time the increasing dominance of this non-native tree in active agroforests is a concern when considering the role of agroforests in a landscape scale conservation strategy. [ABSTRACT FROM AUTHOR]

Abstract: There are many impacts during a tree''s life that affect bole development. In Maesopsis eminii, a high-potential timber species in Uganda, studies have shown that the occurrence of strongly bent boles is the overwhelming reason that boles fail quality criteria. This observation is incongruous with the tree architecture model of Roux, which describes M. eminii as a tree with a strong apical dominance, meaning that it has a strong genetically based preference for vertical growth of the terminal sprout relative to side branches. As external causes for bent boles could be excluded, we demonstrate in this study the proof of heliotropic growth, i.e. an active bending towards light, for M. eminii beyond the sapling stage. We develop a model used to describe the effects of competition on bole quality using bole form parameters and basic information about the neighbouring trees, and without having to incorporate crown parameters. By means of calculated bole parameters and a mathematical equation to calculate the intensity and direction of competition, we prove the existence of a heliotropic growth reaction. However, we are not able to predict the intensity of this reaction. Finally, general silvicultural recommendations are discussed for tree species with strong heliotropic growth. [Copyright &y& Elsevier]

Historical fragmentation and a current annual deforestation rate of 1.2% in the Western Ghats biodiversity hotspot have resulted in a human-dominated landscape of plantations, agriculture, and developed areas, with embedded rainforest fragments that form biodiversity refuges and animal corridors. On private lands in the Anamalai hills, India, we established restoration sites within three rainforest fragments (5, 19, and 100 ha) representing varying levels of degradation such as open meadow, highly degraded sites with dense Lantana camara invasion, abandoned exotic tree plantations ( Eucalyptus grandis and Maesopsis eminii), and sites with mixed-native and exotic tree canopy. Between 2000 and 2004, we planted annually during the southwest monsoon 7,538 nursery-raised seedlings of around 127 species in nine sites (0.15–1.0 ha). Seedlings monitored at 6-monthly intervals showed higher mortality over the dry season than the wet season and survival rates over a 2-year period of between 34.4 and 90.3% under different site conditions. Seedling survival was higher in sites with complete weed removal as against partial removal along planting lines and higher in open meadow and under shade than in sites that earlier had dense weed invasion. Of 44 species examined, survival across sites after 24 months for a majority of species (27 species, 61.4%) was higher than 50%. Retaining regenerating native species during weed clearing operations was crucial for rapid reestablishment of a first layer of canopy to shade out weeds and enhance survival of shade-tolerant rainforest seedlings. [ABSTRACT FROM AUTHOR]

Tree root pruning is a potential tool for managing belowground competition when trees and crops are grown together in agroforestry systems. We investigated the effects of tree root pruning on shoot growth and root distribution of Alnus acuminata (H.B. & K.), Casuarina equisetifolia L., Grevillea robusta A. Cunn. ex R. Br., Maesopsis eminii Engl. and Markhamia lutea (Benth.) K. Schum. and on yield of adjacent crops in sub-humid Uganda. The trees were 3 years old at the commencement of the study, and most species were competing strongly with crops. Tree roots were pruned 41 months after planting by cutting and back-filling a trench to a depth of 0.3 m, at a distance of 0.3 m from the trees, on one side of the tree row. The trench was reopened and roots recut at 50 and 62 months after planting. We assessed the effects on tree growth and root distribution over a 3 year period, and crop yield after the third root pruning at 62 months. Overall, root pruning had only a slight effect on aboveground tree growth: height growth was unaffected and diameter growth was reduced by only 4%. A substantial amount of root regrowth was observed by 11 months after pruning. Tree species varied in the number and distribution of roots, and C. equisetifolia and M. lutea had considerably more roots per unit of trunk volume than the other species, especially in the surface soil layers. Casuarina equisetifolia and M. eminii were the tree species most competitive with crops and G. robusta and M. lutea the least competitive. Crop yield data provided strong evidence of the redistribution of root activity following root pruning, with competition increasing on the unpruned side of tree rows. Thus, one-sided root pruning will be useful in only a few circumstances. [ABSTRACT FROM AUTHOR]

Maesopsis eminii (family Rhamnaceae) is a light hardwood timber species. The trees have whitish bole that are straight and cylindrical when grown in plantation and tend to lean towards sunlight when found to grow among other tree species. The sapwood is almost white in colour and the heartwood yellowish when freshly cut, darkening to golden brown or dark brown on exposure. The texture of wood is moderately coarse and even, with interlocked grain that produces a clear figure on quarter-sawn surfaces. The timber air-dry density at 15% moisture content of a 42-year-old tree was found to be 640-720 kg m-3 and that of a 6-year-old tree, 575-644 kg m-3. Its density suggests that the timber is useful for general utility and other purposes. [ABSTRACT FROM AUTHOR]

Early successional tree species typically attract numerous generalist frugivores, many of which serve as seed dispersers. This study evaluated whether several such dispersers facilitated the invasion of an exotic, early successional tree species, Maesopsis eminii (Rhamnaceae), in submontane forests of the East Usambara Mountains, Tanzania. The primary seed dispersers and their dispersal effectiveness were determined through focal watches at eight trees. Only 3 of 13 frugivores that consumed Maesopsis fruits functioned as seed dispersers (silvery-cheeked hornbill Ceratogymna brevis, Fischer's turaco Tauraco fischeri and blue monkey Cercopithecus mitis). On average, hornbills dispersed >26 times more seeds than monkeys, and >3 times as many seeds as turacos per visit and were thus considered the most important disperser. Seed germination was not affected by gut passage through hornbills. Germination in four microhabitats was experimentally evaluated to determine whether microhabitat influences germination success. Large gaps and forest edges had significantly higher germination rates compared with understorey locations; the germination rate in small gaps was not significantly different from that in the understorey. Expansive Maesopsis invasion in the East Usambaras was likely enhanced in both rapidity and scale by the presence of an extremely effective dispersal agent, the silvery-cheeked hornbill. [ABSTRACT FROM PUBLISHER]

• M. eminii seeds is promising bio-oil source for biodiesel production. • Bio-oil has desirable fatty acids for biofuel application. • Refining oil from M. eminii seeds via UASE results in high yield. In this study, the central composite design of response surface methodology was employed as a design of an experiment to optimize the extraction of oil from Maesopsis eminii seeds using ultrasonic-assisted solvent extraction (UASE). The most appropriate values of operating variables such as extraction time and n-hexane to biomass ratio and its effects on oil yield were analyzed. The 7:1 n-hexane-to-biomass ratio (140 mL n-hexane/20 g seed powder) and the 20 min extraction time were found as optimum conditions to get an oil yield of 47.86 ± 0.09 %. Oil's chemical characteristics and compositions include yellowish color, 0.90 g/mL density, 5.40 pH, 47.9 mm2/s kinematic viscosity, 39.63 MJ/kg high heating value, >200 °C flashpoint, and 0.36 ± 0.05 % free fatty acid content. The analyses of Fourier Transform Infrared Radiation (FTIR) and Gas Chromatography-Mass Spectrophotometry (GC–MS) revealed that oil from the M. eminii seeds has esters and looked-for fatty acids signifying its potential for biodiesel production. Major fatty acids include oleic (36.7 %), linoleic (24.3 %) and stearic (22.6 %) with minor components shared by palmitic (10.2 %), arachidic (2.6 %), y-linolenic (1.5 %), cis-11-eicosenoic (1.5 %) and behenic (0.5 %). The exploratory oil refining via UASE and transesterification resulted in 84.6 % biodiesel yield indicating its high conversion rate and demonstrating its potential as a feedstock for green diesel production. Hence, the coming of the liquid biofuel from the unexplored non-edible M. eminii seeds would benefit humanity and the environment as this would reduce the use of petroleum-based fuels that are known for producing much air pollution in the atmosphere. [ABSTRACT FROM AUTHOR]