Woody Plant Species Diversity Research Articles

Spatial variation and determinants of woody plant species diversity in a semi-humid evergreen broad-leaved forest in the Jizu Mountains, Yunnan

Spatial variation and determinants of woody plant species diversity in a semi-humid evergreen broad-leaved forest in the Jizu Mountains, Yunnan

Floristic composition and community analysis of woody species in Hereje Natural Forest, southwest Ethiopia

The floristic composition, diversity, and conservation status of woody plant species in Ethiopia are determined in this study. Data on vegetation are collected using a systematic random sampling method from 45 20 m × 20 m (400m2) plots laid every 100 m along four parallel transect lines running from south to north. The Flora of Ethiopia and Eritrea identification key (Volume I–VIII) is used to identify the scientific names of all woody plant species. The Shannon–Wiener diversity index is used to calculate species diversity, whereas Sorensen's similarity coefficient is used to assess similarities and differences among plant communities. The studied forest contains 44 plant species from 29 families and 40 genera. The Fabaceae is the most dominant family, followed by the Rubiaceae and Combretaceae. In terms of habit, the collected woody species consisted of 30 (68.2%) trees and 14 (31.8%) shrubs. The two most frequent species are Syzygium guineense (51.11%) and Maytenus gracilipes (46.66%). Three plant community types are identified using Agglomerative Hierarchical Cluster Analysis. Most species (Calpurnia aurea-Combretum molle) are observed in community type two. The study is generally limited to the floristic and diversity of woody plant species. Therefore, a thorough investigation of all species' floristic composition, population structure, regeneration status, and ecological aspects is recommended.

Species Composition, Structure, and Regeneration Status of Woody Plants and Anthropogenic Disturbances in Zijje Maryam Church Forest, Ethiopia.

Our current study was conducted in Zijje Maryam Church Forest, Ethiopia, to explore woody species composition, structure, regeneration status, and anthropogenic disturbances inside the sacred groves. The aforementioned information for adequate conservation and management of the church forest is not well documented. Fifteen main quadrats each having an area of 625 m2 (25 m × 25 m) were used for vegetation and disturbance data collection. Determination of the sampled quadrats was based on the principle that minimum quadrats give the smallest possible area in which all species occurring in the church forest are present. All woody species with a diameter at breast height (DBH) ≥ 2.5 cm within the quadrat were identified, counted, and their height and DBH data were recorded. The criterion to start at DBH ≥ 2.5 cm was to exclude seedlings having DBH < 2.5 cm and height ≤0.6 m. Sapling and seedling data were collected using 45 saplings and 45 seedling quadrat that measured 4 m2 and 1 m2, respectively. Vegetation data analysis and ANOVA were used for statistical comparison. A total of 48 woody plant species belonging to 46 genera and 36 families were identified. Fabaceae was the dominant family containing 5 species followed by Rosaceae with 3 species. Total basal area of the church forest was 83.03 m2 ha-1. The density of seedlings, saplings, and matured woody species stem ha-1 were 15555, 3833, and 865, respectively. Talking these densities, the regeneration status of the forest was good. The Shannon diversity and evenness of woody plant species in the forest was high, 3.29 and 0.85, respectively. Juniperus procera 27.67 (9.22%) and Olea europaea were species with the highest IVI. Nearly, 22% of areas of the forest get disturbed and higher anthropogenic disturbances occurred near the edge of the forest. Gathering, clearing, and grazing are the major human disturbances that stakeholders need to tackle for conservation. Zijje Maryam Church Forest has heterogeneous species composition with varied seedlings and saplings. Therefore, local conservation policies recommended not only protect large forests, but also the small and valuable forests service to the needs of local people.

Past and present effects of habitat amount and fragmentation per se on plant species richness, composition and traits in a deforestation hotspot

Worldwide, human activities are rapidly changing land cover and its spatial configuration. While it is widely acknowledged that habitat loss is a major cause of biodiversity loss, there is less agreement on how biodiversity responds to changes in habitat configuration. We assessed the effects of forest amount and forest fragmentation per se (the number of patches for a given forest amount, an aspect of configuration) on woody species richness, composition, and traits in the Dry Chaco forest, a global deforestation hotspot. We sampled woody plants in 24 forest sites varying in forest amount and fragmentation per se in the surrounding landscapes. Using Generalized Linear Modeling we tested whether a model with just forest amount was at least as able to predict species richness as a model with either patch size or isolation or the combination of both. We also tested whether forest amount and fragmentation per se influenced species richness, composition, and the density of four species traits. Finally, we compared these responses to forest amount and fragmentation per se measured in the past (2009) vs. in the present (2017) to look for time-lagged responses. We found that: 1) in support of the habitat amount hypothesis, species richness was more strongly related to forest amount than to the size and/or isolation of the forest patch containing the sample plot; 2) the positive effect of forest amount on species richness was more important than the effect of fragmentation per se (also positive); 3) fragmentation per se changed species composition such that plots in landscapes with more fragmented forest had species with smaller leaves and seeds, and higher wood density; and 4) species richness showed a time-lagged response to forest amount but not to forest fragmentation per se. Our results suggest that preservation of native Dry Chaco forest should be prioritized regardless of its fragmentation level, for conserving woody plant species diversity.

Size-dependent associations of woody plant structural diversity with soil C:N:P stoichiometry in a subtropical forest

Woody plant structural diversity and soil C:N:P stoichiometry have widely been examined for their spatial patterns and changes across environmental gradients, but the interactions and relationship of these biotic and abiotic variables have not been well understood. Here, we investigated the associations of woody plant structural diversity variables with soil total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP), and their stoichiometry. We found only weak associations between soil C:N:P stoichiometry and species diversity variables, however, stronger significant associations were detected between C:N:P stoichiometry and species diversity variables for the adult trees and saplings when analyses were carried out with appropriate size stratification of woody plants. Most size diversity variables were significantly correlated with TOC, TN, TP, and their stoichiometric ratios, and the size diversity variables were greater in strength than species diversity in their associations with TOC, TN, TP, and C:N:P stoichiometric ratios. In most cases, C:N:P stoichiometric ratios were more sensitive than TOC, TN, or TP in predicting species diversity and size diversity. Our findings demonstrate that the associations of woody plant species diversity with TOC, TN, TP, C:N:P stoichiometry are size-dependent, and the size diversity is much more sensitive than species diversity in predicting the change of soil TOC, TN, TP, and C:N:P stoichiometric ratios. These findings also suggest that an appropriate size stratification will help demonstrate the linear relations between woody plant structural diversity and C:N:P stoichiometry and amplify the environmental signals from soil factors in predicting the biotic variables.

Ecological Assessment of Woody Plant Diversity and the Associated Threats in Afromontane Forest of Ambericho, Southern Ethiopia

Abstract Mountainous ecosystems provide social, economic, and environmental services at different scales. Nonetheless, currently, they have been exposed to environmental degradation risks. This study was conducted to investigate woody plant species diversity and threats to the study forest. Systematic sampling was employed to collect vegetation data from fifty 400 m2 sample plots along five transect lines. Vegetation and the environmental variables were recorded from each plot. Eighty randomly sampled households were selected for socioeconomic data. Descriptive statistics and ranking exercises were employed. The vegetation classification was performed using the R program version 2.15.2. The species diversity, richness, and evenness were computed. The result showed that five plant communities were recognized. A total of 99 woody plants belonging to 87 genera and 50 families were identified, of which 13 % were endemic. The total basal area of the study forest was 3.40 m2ha-1, and the forest was characterized by a bell-shaped population structure identified by poor regeneration and recruitment. With increasing altitude, there was a significant decrease in human impacts, grazing, and the number of plant species. About 90 % of the informants disclosed deforestation as the major threat to forest cover change, whereas 84 % of them recommended forest restoration as a tangible measure. There was a high deforestation rate of the selected woody species (e.g., Arundinaria alpina) and high expansion of agriculture at the fringes of the forest. This requires promoting forest land rehabilitation activities, nature tourism, establishing partnerships with communities on the forest management, consolidating village-level institutions and developing livelihood alternatives for communities at the local governments and the community level to restore the degraded forest.

Impacts of Parthenium hysterophorus L. on Plant Species Diversity in Ginir District, Southeastern Ethiopia

Invasive alien species are considered the second greatest global threat to biodiversity. This study is aimed at determining the impacts of Parthenium hysterophorus on herbaceous and woody plant species diversity in the Ginir district, southeast Ethiopia. Data on vegetation were collected from the three study sites’ four land use types, with each land use type having invaded and non-invaded land units. A systematic random sampling method was used for establishing sampling plots. To examine the impacts of the invasive on native plant diversity, a total of 160 plots (120 plots of 1 m2 on grazing lands, roadsides, and abandoned agricultural lands and 40 plots of 20 m2 for sampling herbaceous and tree (shrub) species, respectively) were established. The number of plots was equally distributed in both invaded and adjacent non-invaded areas. Plant species from each plot were recorded and identified. In each plot, all the individuals of P. hysterophorus were counted, the heights of the five tallest individuals were measured, and the mean height was calculated. The percentage cover of P. hysterophorus was visually estimated. The data were analyzed using both descriptive and inferential statistics. A total of 105 plant species (45 trees/shrubs and 60 herbaceous) belonging to 84 genera and 42 families were documented in the study area. The result showed a strong negative relationship between the density of P. hysterophorus and other plant species richness (r = −0.82, p = 0.013) and species abundance (r = −0.917, p = 0.001) per study site of the invaded community. Species richness in the non-invaded site was higher (105 species) than in the invaded area (63 species), demonstrating the negative impact of P. hysterophorus on local biodiversity. Furthermore, the number of plant families was 42 in the non-invaded area, in contrast to only 32 in the invaded areas, a 23.8% decline. Of the plant communities, similarity indices between non-invaded and invaded sites among different land use types were &gt;50%. It was concluded that P. hysterophorus was one of the most dominant invasive alien species in the study area that reduced the species diversity of various plant species. Putting in place a strategy and effective planning for the control and management of this invasive alien species is strongly recommended.

Indigenous people’s approach to woody plant species conservation in selected spots in Abia State, Southeastern Nigeria

The 15th of United Nations’ Sustainable Development Goals (SDGs) aims to protect, restore, and promote sustainable use of terrestrial ecosystems, sustainably manage forests, combat desertification, and halt and reverse land degradation and halt biodiversity loss. This paper investigates the approach adopted by indigenous peoples for conservation of woody plant species diversity in some selected spots in Abia State, Southeastern Nigeria. Relying on mixed method approach to research, data collection comprising field observation, ground truthing, plant species inventory, and key-informant interviews and analysis of data, two spots were purposively sampled, one from each of the two LGAs; Mbom in Bende LGA and Amangwu in Ohafia Local Government Area (LGA). A 50 × 20 m quadrat was sampled from each site, from where plant species inventory was undertaken. Shannon– Wiener diversity index (H’) was used to analyse the data. The result of Shannon–Wiener diversity index, shows that the diversity indices of the plant species for the two sites were 3.20 (Mbom) and 3.95 (Amangwu) respectively. The people of Bende and Ohafia LGAs employ some traditional laws to ensure conservation of woody plant species so as to achieve goal 15th of the SDGs. This paper advocates sustenance of those traditional laws that encourage conservation of woody plant species in the study area with enforceable sanctions to deter defaulters.

Analysis of Urban Woody Plant Diversity among Different Administrative Districts and the Enhancement Strategy in Changchun City, China

Species diversity plays an important role in urban ecosystem stability and sustainability. Research on woody plant diversity among different administrative districts is vital to effectively improving urban biodiversity. In this study, a stratified random sampling method was used to set the sample plot, a spatial mapping of the diversity indices was conducted, and methods of principal component analysis and similarity analysis were used to analyze the species composition and dissimilarity among different administration districts. Finally, the model based on the relationship between the diversity indices and forest landscape pattern indices was built. The results showed that woody plant species diversity differed significantly among different administrative districts in Changchun. The species diversity levels in the Qikai (QK), Lvyuan (LY), and Kuancheng (KC) districts were higher, and those in the Nanguan (NG) and Erdao (ED) districts were lower. The species composition of every district basically complied with the 10/20/30 “rule of thumb”. The most common species, genera, and families in urban forests should not exceed the proportion of the total abundance of all species. There was a significant correlation between the diversity indices and the forest landscape indices of each district. The Margalef index (dMa) and the Shannon–Wiener index (H′) decreased significantly while CONTIG-MN increased, and increased significantly while LSI increased. Species evenness index J decreased significantly while LPI increased, and increased significantly while DIVISION increased. In future tree species selection, native tree species should be given priority as much as possible, the planting of Salicaceae should be reduced, and the species diversity of each district should be increased. Chaoyang (CY), ED, and LY districts should strengthen the links between forest patches.

Tree diversity and vegetation structure of the tropical evergreen forests of the southern slopes of Meghalaya, North East India

Abstract. Tynsong H, Dkhar M, Tiwari BK. 2022. Tree diversity and vegetation structure of the tropical evergreen forests of the southern slopes of Meghalaya, North East India. Asian J For 6: 22-33. In the tropical evergreen forests of the southern slopes of Meghalaya, North East India, we examined the plant species diversity and community structure of woody plant species. The forests chosen for this study represent the area's primary vegetation. We counted a total number of 6016 individual trees belonging to 146 species, 95 genera, and 56 families from three 1-ha plots. The Shannon-Wiener Index (H') of the tree species in the three forest stands ranged from 3.74 to 3.95, the dominance of Simpson's index from 0.02 to 0.04, the evenness index from 0.68 to 0.83, and Margalef index range from 23.07 to 27.39. The density of woody species ranged from 1944 to 2100 trees ha-1 (mean 2005 ± 48.01). The dominant families based on Importance Value Index (IVI), number of species, genera and individuals were Fagaceae (IVI = 205.29, species= 11, genera= 4 and number of individuals= 1184), Lauraceae (IVI = 139.42, species= 22, genera= 9 and Individual= 882) and Euphorbiaceae (IVI = 68.39, species= 17, genera= 8 and Individual=478). Arecaceae represented by Arenga pinnata (Wurmb) Merr. and Caryota sp. and Pandanaceae, represented by Pandanus odoratissimus Blume, were the only monocot families, and Pinaceae, the sole gymnospermic family, represented by Pinus kesiya Royle ex Gordon. This study offers valuable knowledge about the species diversity and community structure of trees which is a prerequisite for efficient management and protection of the forests conserved by the local village communities primarily for ecosystem services.

Effects of resumption of undercutting by environmental taxes on the species diversity of woody plants on the forest floor of a deciduous coppice forest

Effects of resumption of undercutting by environmental taxes on the species diversity of woody plants on the forest floor of a deciduous coppice forest

Impacts of Climatic Factors on Vegetation Species Diversity, Herbaceous Biomass in Borana, Southern Ethiopia

The study was conducted in three districts of Borana Zone, with the objective to determining the impacts of climatic factors on vegetation species diversity, herbaceous biomass yield of Borana rangelands under commonial grazing rangeland types during end of growing season. The most types rangeland of communial properties are traditional enclosure and continuous grazing rangeland from in where our different data were collected. Within both rangeland types of each districts 20 m x 20 m plots that placed at 200 m distances intervals with three replication was used to collect woody vegetation. The data of herbaceous plant community was collected from seventeen quadrants (1 m x1 m) that layout in the main plot. The collected data was analyzed by linear regression to determine the impact of climate factors. The herbaceous species richness, diversity and biomass study sites had highly significantly difference (P &lt; 0.001) and positive linear with mean annual precipitation. There is significantly difference (P &lt; 0.05) and negative linear in woody species richness and diversity. Both herbaceous and woody plant species richness and diversity of study areas had a negative linear with mean annual temperature. Climate factors specieally rianfall have a great impact on rangeland ecosystems of study areas. Therefore, rangeland user should be considering climatic factors to improve productivity of rangeland. Keywords: Rangeland types, Species diversity and richness, herbaceous biomass and rainfall DOI: 10.7176/JEES/12-5-01 Publication date: May 31 st 2022

Comparing Elevational Patterns of Taxonomic, Phylogenetic, and Functional Diversity of Woody Plants Reveal the Asymmetry of Community Assembly Mechanisms on a Mountain in the Hengduan Mountains Region

The contributions and interaction of biotic and abiotic processes in community assembly are crucial for understanding the elevational patterns of biodiversity. The combined analyses of taxonomic, phylogenetic, and functional diversity are necessary to resolve this issue. By investigating vegetation in 24 transects sampled on Hongla Snow Mountain, in the central Hengduan Mountain Ranges in Southwest China, we delineated the elevational vegetation spectrum on the eastern and western slopes, analyzed the elevational variation in taxonomic, phylogenetic, and functional diversity of woody plant species, and compared the community structure of phylogeny and function in the low-elevational shrublands, mid-elevational forests, and alpine shrubs and meadows. The species richness, phylogenetic diversity, and functional diversity of woody plants showed nonstandard hump-shaped patterns with two peaks along the elevational gradient. The community structure of phylogeny and function (including tree height, leaf area, specific leaf area, leaf thickness, bark thickness, and wood density) clustered in the low-elevation shrub communities, being random and over-dispersed in mid-elevational forests. The phylogenic structure was over-dispersed in alpine communities, whereas the functional structure was clustered. Elevational patterns in taxonomic, phylogenetic, and functional diversity, together with the mean and variation in woody plant functional traits, suggested drought stress and freeze stress as environmental filters dominating the assembly of low and high elevation non-forest communities, and a conspicuous effect of biotic facilitation was also suggested for alpine habitats. By contrast, interspecific competition dominated the community assembly of forests at mid-elevations. The difference in biodiversity indices between the west and east slopes reflected the effects of the Indian Monsoon on the geomorphic patterns of ecosystem structure. These results increased our understanding of biodiversity patterns and underlying mechanisms in the Hengduan Mountains of Southwest China and highlighted the priorities for biodiversity conservation in this region.

Species diversity and state of woody plants of the Lugansk State Agrarian University

The estimation of the modern state of arboreal plants of the dendropark of the Lugansk State Agrarian University was first given. It was set that now 5712 copies of trees, bushes and lianas, related to 104 species from 63 genus and 29 families, sprout on this territory. Dominant position is occupied by trees - 55.6%, bushes - 37.0% and lianas - 7.4%. The conditions of Aesculus hippocastanum L., Betula pendula Roth, Populus alba L. and Populus nigra L. are caused an alarm. The arboreal planting on territory of university can served as basis for organization of a botanical garden.

Patterns in plant species diversity along the altitudinal gradient in Dhauladhar mountain range of the North-West Himalaya in India

The objective of the present study was to understand the patterns in plant species diversity along the altitudinal gradient in Dhauladhar mountain range of the Indian Himalayas. Nested plot method was employed for sampling trees, shrubs and herbs along the elevations from sub-tropical forests to sub-alpine forests, and Shannon-Weiner diversity index was used for calculation of plant species diversity. A total of 10 forest communities were identified, of which the highest number of forest communities and woody species diversity were found in the temperate forests. Though, there are multiple ecological factors and their combinations which determine the distribution and diversity of plant species in an ecosystem, the present study reveals that elevation is one of the major abiotic factors in the Himalayan mountains, which determines the establishment and distribution of various forest communities and species diversity. Along an altitudinal gradient there was a hump-shaped curve in the species diversity of woody plant species whereas the species diversity of herbaceous species increased with elevations from sub-tropical to sub-alpine forests. This fact needs to be employed while making policies and planning for the sustainability of forests along the altitudinal gradients in the mountains.

Urbanization strengthens the edge effects on species diversity and composition of woody plants in remnant forests

Urban remnant forests are embedded in urban areas and are threatened directly and indirectly by urbanization. The direct effects (e.g., loss of area) have been well studied. However, knowledge about the indirect influence of urbanization through edge effects on the biodiversity in remnant forests is limited. In this study, we surveyed woody plant species in 72 plots in nine remnant forest patches in Guiyang, China. We examined the influences of urbanization and edge effects on the species diversity and composition of woody plants in remnant forests. We compared alpha diversities and quantified compositional dissimilarities in interior and edge sites at different levels of urbanization. We also measured the niche width of the recorded plant species and assessed whether high levels of urbanization and edge effects increased the number of generalist species. The Shannon index, the Simpson index and the Pielou index of adult trees were lowest in the edge habitat under high levels of urbanization. Significant differences in the Shannon index and the Simpson index of sapling/seedling were detected between interior and edge sites under low urbanization. The edge effects on the species composition of adult trees were intensified by high levels of urbanization. Woody plant species with wide niche widths were more abundant at edge sites under high levels of urbanization. Therefore, we recommend that urban expansion surrounding remnant patches should be strictly controlled to alleviate edge effects on biodiversity. ● Urbanization increased edge effects on the woody plants of remnant forests in Guiyang, China ● Plant species with wide niche widths were more abundant at edge sites under high levels of urbanization ● More attention should be paid to control the further urban expansion surrounding remnant forests to alleviate the edge effects on biodiversity

Assessment of woody plant species composition in secondary deciduous forests of Odisha, India

Plant species composition according to their functional types, distribution pattern are crucial for biodiversity conservation in tropical deciduous forest. The study assessed the woody plant species diversity, stand structure and population density in the secondary deciduous forest of Chandaka wildlife sanctuary, Odisha, India. A total of 70 species belonging to 63 genera and families were documented in this study.The stem density was found to be 1080 stems/ha with reverse J-shaped population structure indicating good regeneration potential of the forests. Shannon diversity Index varied from 0 to 2.31 whereas Simpson's index varied from 0 to 0.85. The correlation study between Importance Value Index and basal area were significant (p=40.63). The present study would be helpful for conservation and management of biodiversity in secondary dry deciduous forests of Chandaka Wildlife Sanctury in particular and tropical dry forests in general.

Wildfire and topography drive woody plant diversity in a Sky Island mountain range in the Southwest USA.

AimDrastic changes in fire regimes are altering plant communities, inspiring ecologists to better understand the relationship between fire and plant species diversity. We examined the impact of a 90,000‐ha wildfire on woody plant species diversity in an arid mountain range in southern Arizona, USA. We tested recent fire‐diversity hypotheses by addressing the impacts on diversity of fire severity, fire variability, historical fire regimes, and topography.LocationChiricahua National Monument, Chiricahua Mountains, Arizona, USA, part of the Sky Islands of the US–Mexico borderlands.TaxonWoody plant species.MethodsWe sampled woody plant diversity in 138 plots before (2002–2003) and after (2017–2018) the 2011 Horseshoe Two Fire in three vegetation types and across fire severity and topographic gradients. We calculated gamma, alpha, and beta diversity and examined changes over time in burned versus unburned plots and the shapes of the relationships of diversity with fire severity and topography.ResultsAlpha species richness declined, and beta and gamma diversity increased in burned but not unburned plots. Fire‐induced enhancement of gamma diversity was confined to low fire severity plots. Alpha diversity did not exhibit a clear continuous relationship with fire severity. Beta diversity was enhanced by variation in fire severity among plots and increased with fire severity up to very high severity, where it declined slightly.Main ConclusionsThe results reject the intermediate disturbance hypothesis for alpha diversity but weakly support it for gamma diversity. Spatial variation in fire severity promoted variation among plant assemblages, supporting the pyrodiversity hypothesis. Long‐term drought probably amplified fire‐driven diversity changes. Despite the apparent benign impact of the fire on diversity, the replacement of two large conifer species with a suite of drought‐tolerant shrubs signals the potential loss of functional diversity, a pattern that may warrant restoration efforts to retain these important compositional elements.

Woody Plant Species Diversity of Lay Agerit Giorgis Natural Forest, Merabeti District of North Shoa Zone in Amhara Region, Ethiopia

Ethiopia is one of the biodiversity reach areas in the world. This study was conducted in Lay Agerit Giorgis forest is located in Merabeti district of North Shoa zone in Amhara region. This inventory was done with the aimed of woody plant species diversity documentation; determine floristic composition and regeneration status of woody plant species in Lay Agerit Giorgis Natural Forest. Systematic sampling was employed for the purpose of woody plant inventory in this area. The total of 34 quadrates were established with 6 transects in each of them 100meter apart and also 100meter distance in between plots with the sample plot area enumerated as the 10X 50meter. The major forest disturbance factors were recorded 35.16% light and moderate Browsing, 36.26% light and moderate Grazing and 28.57% light and moderate disturbance levels shows by logging /cutting. A total of 48 woody plant species belong to 38 genera and 27 families were recorded. The most frequent genera in the woodland were (Fabaceae), (Capparidaceae), (Celastraceae) and (Tiliaceae), respectively. The species frequency ranges between 2.94 – 76.4% with Dichrostachys cinerea (74.4%), Acacia tortilis (67.6%), each Dodonaea angustifolia and Euclea racemosa (64.7%) are among the top and Gardenia ternifolia, Ficus sur, Commiphora africana, Celtis africana are among the lowest in frequency distribution (2.94%). Setting high priority is needed to conserve these endangered woody plant species following either the ex-situ or field Gene bank or both conservation systems.

Species diversity and stand structural diversity of woody plants predominantly determine aboveground carbon stock of a dry Afromontane forest in Northern Ethiopia

Aboveground carbon (AGC) stock in forests is affected by several biotic and abiotic factors. Understanding those factors is crucial in managing forests for climate change mitigation and other ecosystem services. This study examined effects of diversity attributes (species and stand structural diversity of woody plants) and topographic attributes (altitude and slope) on AGC stock of a dry Afromontane forest. Data from individual woody plants for estimating AGC were collected from 252 plots (20 × 20 m) established in a systematic grid (2 × 2 km) covering the entire forest area. Woody plant diameter diversity and woody plant height diversity were used as proxies for stand structural diversity. Structural equation modelling was applied to test the effects of the selected attributes on AGC stock, and together they explained 71% of the variation. Stand structural diversity was the most important driving factor for the AGC stock. Woody plant species diversity had both direct and indirect effects on AGC stock, but the indirect effect through its influence on stand structural diversity was more pronounced. Altitude and slope were both negatively but weakly associated with AGC stock. Our results provide insight on the effects of diversity and topographic attributes on AGC stock, which can assist future management of the forest. Enhancing stand structural diversity by means of selection cutting systems and woody plant species diversity by means of enrichment planting can be effective treatments. When considering dry Afromontane forests’ widespread distribution, the potential contribution in carbon sequestration and thereby mitigating climate change is substantial. Hence, the results and management suggestions from the present study may have practical interest for the management of dry Afromontane forests not only in Ethiopia but also in Africa at large.