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Modeling effects of abiotic factors on the abundances of eight woody species in the Harana forest using artificial networks,random forest, and generalized linear models

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Ecological Processes 2023年第1期12卷 153-166页

作者： Girma Ayele Bedane Gudina Legese Feyisa Feyera Senbeta Wakjira Center for Environmental Science College of Computational and Natural Science Addis Ababa University Centre for Environment and Development College of Development Studies Addis Ababa University

Background Abiotic factors exert different impacts on the abundance of individual tree species in the forest but little has been known about the impact of abiotic factors on the individual plant, particularly, in a tropical forest. This study identified the impact of abiotic factors on the abundances of Podocarpus falcatus, Croton macrostachyus, Celtis africana, Syzygium guineense, Olea capensis, Diospyros abyssinica, Feliucium decipenses, and Coffea arabica. A systematic sample design was used in the Harana forest, where 1122 plots were established to collect the abundance of *** forest（RF）, artificial neural network（ANN）, and generalized linear model（GLM） models were used to examine the impacts of topographic, climatic, and edaphic factors on the log abundances of woody species. The RF model was used to predict the spatial distribution maps of the log abundances of each *** The RF model achieved a better prediction accuracy with R2= 71% and a mean squared error（MSE） of 0.28for Feliucium decipenses. The RF model differentiated elevation, temperature, precipitation, clay, and potassium were the top variables that influenced the abundance of species. The ANN model showed that elevation induced a negative impact on the log abundances of all woody species. The GLM model reaffirmed the negative impact of elevation on all woody species except the log abundances of Syzygium guineense and Olea capensis. The ANN model indicated that soil organic matter（SOM） could positively affect the log abundances of all woody species. The GLM showed a similar positive impact of SOM, except for a negative impact on the log abundance of Celtis africana at p woody species may vary wit

关键词： species distribution model Random forest Artificial neural network Generalized linear model species abundance woody species Environmental variable

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species diversity,population structure and regeneration of woody species in fallows and mature stands of tropical woodlands of southeast Angola

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Journal of Forestry Research 2018年第6期29卷 1569-1579页

作者： Francisco M.P.Goncalves Rasmus Revermann Manuel J.Cachissapa Amandio L.Gomes Marcos P.M.Aidar Herbarium of Lubango ISCED HuilaSarmento Rodrigues Str.230 LubangoAngola Biocentre Klein Flottbek University of HamburgOhnhorststr.1822609 HamburgGermany Department of Biology Faculty of SciencesAgostinho Neto UniversityAv.4 de Fevereiro 714th FloorLuandaAngola Plant Physiology and Biochemistry Institute of BotanyCP 3005Sao PauloSP CEP:01061-970Brazil

This study in the dry tropical woodlands of SE Angola in Cuando-Cubango Province assessed the diversity and composition of woody species in fallows compared to those in mature woodlands. We assessed the population structure of the most harvested woody species by calculating size class distribution and evaluated their regeneration potential based on the density of saplings. The vegetation was surveyed in 20 plots of 20 × 50 m(1000 m2). In each plot, we measured the diameter at breast height(DBH) of all woody species with DBH ≥ 5 cm. The saplings were counted, identified and recorded; 718 individuals, corresponding to 34 species in 32 genera and 15 families were recorded. The size class distribution of target woody species showed three different patterns in fallows and mature woodlands. In general,most of the smaller diameter classes had more individuals than the larger ones did, showing that the regeneration may take place. However, in some diameter classes, the absence of larger stems indicated selective logging of larger trees. Few saplings were recorded in the fallows or mature woodlands; fire frequency and intensity is probably the main obstacle for seed germination and seedling survival rates in the studied area.

关键词： Baikiaea woodlands Fallows Mature woodlands Regeneration woody species

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Regeneration Potential of woody species at the Side of Secondary Roads Post-Logging of Loundoungou-Toukoulaka Forest Management Unit, Republic of the Congo

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Natural Resources 2023年第7期14卷 102-120页

作者： Chauvelin Douh Larisa Mbouchi Malonga Donatien N’zala Belvina Chardène Mabengo Christian Moussoumbou Saint Fédriche Ndzaï Félix Koubouana Marien N’Gouabi University Superior National School of Agronomy and Forestry (ENSAF) Laboratory of Geomatics and Applied Tropical Ecology (LGETA) Brazzaville Republic of the Congo National Forestry Research Institute (IRF) Department of Forest Ecology Scientific City of Brazzaville Brazzaville Republic of the Congo

Natural regeneration is the basis of a dynamic and demographic balance of plant populations. The objective of this study was to assess the natural regeneration potential of woody species along secondary roads post-logging abandoned since 2008 and 2018. In the two Annual Allowable Cuts (AAC 2008 and AAC 2018), 24 regenerating sub-plots (i.e. 12 sub-plots for AAC 2008 and 12 sub-plots for AAC 2018) with a unit area of 5 m × 5 m were delimited with a total area of 0.06 ha (i.e. 0.03 ha for each AAC). The abundance and diversity of woody species were respectively inventoried and estimated. Two estimators of the specific richness were used to estimate the floristic diversity of each Annual Allowable Cuts (AAC). The results reveal globally 88 woody species in the AAC 2008 and 241 woody species in the AAC 2018, with respective average densities of 2933 stem/ha and 8033 stem/ha. There was a very highly significant difference between the mean densities of the two AAC (Kruskal-Wallis test;H = 2.36, p-value woody species in the 2018 AAC compared to the 2008 AAC. Also, the spatial structuring of the sub-plots on the basis of Principal Component Analysis (PCA) demonstrates that the floristic composition of the two AAC is globally different. The study suggests silvicultural interventions and the long-term assessment of regenerating woody species along abandoned secondary roads in order to guarantee the sustainable management of their population.

关键词： Regeneration Dynamics woody species Abandoned Secondary Roads Forest Management Unit

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Structure and regeneration status of woody species in the Munessa Forest,Southern Ethiopia

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Journal of Forestry Research 2021年第2期32卷 493-501页

作者： Mengistu Gelasso Junqing Li Department of Forest Ecology College of ForestryBeijing Forestry UniversityP.O.Box 100083BeijingPeople’s Republic of China

This study evaluates the structure and regeneration status of woody species in the Munessa Forest,a dry Afromontane forest in southern *** data were collected using a systematic sampling *** and distribution of seedlings,saplings and mature trees were assessed along an altitudinal gradient using quadrats of different *** number of individuals,frequencies,heights and DBH of species>1 m and DBH>2.5 cm were recorded in altitudinal bands of 100 *** of the vegetation structure shows that the density of woody species decreases as DBH and height class *** area of stems with DBH>2.5 cm was 53.4 m^(2)ha^(−1).Population structure and regeneration patterns indicate a significant degradation of the forest due to anthropogenic *** was better for less valuable woody species than for species with economic and ecological *** suggests a discontinuous recruitment of these species due to selective cutting of middle and higher diameter ***,enrichment planting of high value,endangered species is necessary to maintain them as part of this *** is a need to develop and implement an effective forest management plan for sustainable use of these forest resources.

关键词： woody species Altitudinal gradient Regeneration status Structural distribution

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Diversity and Importance of Benin’s Forests and Agroforestry Systems woody species in Mortars and Pestles Manufacture

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Open Journal of Forestry 2023年第1期13卷 45-60页

作者： Menson Richard Somanin Baba Kayodé Eben-Ezer Ewedje Akossibe Ismaël Batcho Ezin Paul Ogan Augustin Orou Matilo Cossi Aristide Adomou Hounnakpon Yedomonhan Université Nationale des Sciences Technologies Ingénierie et Mathématiques (UNSTIM) Abomey Bénin Unité de Recherche Forestière Appliquée Direction Générale des Eaux Forêts et Chasses Ministère du Cadre de Vie et du Développement Durable Cotonou Bénin Laboratoire de Botanique et Ecologie Végétale (LaBEV) Faculté des Sciences et Techniques (FAST) Université d’Abomey-Calavi (UAC) Cotonou Bénin

The disappearance of resources with high genetic potential and great utility for people and the challenge of the conservation and sustainable management of these resources are two opposing facts of which the world is now concerned. In Benin, forests and agroforestry systems complement each other in wood supply for mortar and pestle manufacture. Thus, this study aimed to investigate the diversity of woody species used for mortar and pestle manufacture and to analyze the preferences of manufacturers through an ethnobotanical approach. Based on the snowball sampling method, and interviews with 112 manufacturers from different ethnic groups, we identified 31 tree species. These species belong to 30 genera and 13 plant families. The Fabaceae are more represented with 14 species (i.e. 45% of the total). Ten are frequently used. But there are four species, such as Vitellaria paradoxa C. F. Gaertn., Prosopis africana (Guill. & Perr.) Taub., Terminalia glaucescens Planch. ex Benth. and Pericopsis laxiflora (Benth.) Meeuwen, which are highly preferred by manufacturers respectively. The calculation of the Indexes of Possession of Global Knowledge (IPSG) revealed that the ethnic group Nagot (0.204) possessed more knowledge and is followed by Mahi (0.201) and Fon (0.18) respectively. Forests and agroforestry systems are both supply sites for manufacturers. The non-parametric Wilcoxon test proved that there are no significant differences between the species’ preference for mortars or pestles manufacture (v = 181, p-value = 0.38). Since the trees cutting in agroforestry systems can be destructive to them, provisions such as the promotion of agroforestry in rural areas and the integration of the used species in the reforestations programs must be taken to curb the pressure and contribute to the conservation of the biodiversity.

关键词： Agroforestry Systems Benin Diversity Forest Mortars and Pestles Uses woody species

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Analysis on the daily courses of water potential of nine woody species from Cerrado vegetation during wet season

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Journal of Forestry Research 2000年第1期11卷 7-12页

作者：张文辉马瑞萍西北林学院陕西杨凌 Universidade Federal de Sao Carlos 巴西东北林业大学黑龙江哈尔滨

The water potential (Ψ) daily courses of 9 woody species from Cerrado vegetation in different weather conditions during wet season were observed and analyzed. The adjusting strategies of 9 species could be divided into 3 groups according to Cluster Analysis and based on the data observed on the January 18, March 20 and April 6. The Ψ values of the first group, which included 2 species, were maintained at the higher level consistently. The Ψ values of the second group, which included 5 species, were intermediate level. The Ψ values of the third group, which included 2 species, were kept in the lower level. The Ψ values of all species always kept pace with the weather condition, especially water condition. During the clear day only one Ψ value peak for all species occurred at midday (12∶30–13∶30). When the overcast or raining occurred for a short period, the fluctuation of Ψ values would appear after about 15–30 min responding to the change of weather condition. Even in the same group under the same external circumstance, there was a clear variation of the leaf Ψ values among different species, which showed that the strategy diversity for plant to balance water relation. From January to April, the Ψ values of 9 species reduced in response to the drought condition. The species with the lower values of water saturation deficiency at turgid loss point (W sdtlp) the osmotic potential at saturation (πsat), the osmotic potential at turgid lose point (πtip) or lower predawn water potential (Ψpd) usually had the lower Ψ values at midday. The mechanism of water balance controlled by many systems has been assumed.

关键词： Wet season Water balance strategy Osmotic potential Water potential woody species

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woody species Diversity and Structure of Agroforestry and Adjacent Land Uses in Dallo Mena District, South-East Ethiopia

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Natural Resources 2016年第10期7卷 515-534页

作者： Bikila Mengistu Zebene Asfaw Sinana Agricultural Research Center Bale-Robe Ethiopia Wondo Genet College of Forestry and Natural Resources Hawassa University Shashamane Ethiopia

Sustainable farming practice that utilizes and conserves biodiversity, reducing negative impacts of agriculture on biodiversity and provides wood and energy to local community is a good solution to reduce deforestation and forest degradation. This study was carried out in Dallo Mena district of Bale zone to identify woody species diversity in homegarden agroforestry practices, shade grown coffee agroforestry practices and adjacent natural forest, and to show how land use and management practice determine the plant species diversity. The study site was selected based on spatial analogue approach. In each land use, a plots of 10 m × 10 m size was drown by using systematic sampling method following the transect line. A total of 36 sample plots were sampled along the transect line laid down inside each land uses. In each plot, woody species were counted and the diameter and height of trees and shrubs were measured. Based on this inventory a total of 39 woody plant species which are about 23, 10, 15 woody plant species were recorded from natural forest, shade grown coffee agroforestry and homegarden agroforestry practices respectively. These species were classified belonging to 24 families. The Shannon Wiener diversity index used to estimate species diversity ranged from 0.14 to 2.54 with a mean of 1.47. Also 21% woody species similarities were observed between those three land uses. The result shows that both agroforestry practices (shade grown coffee and home garden agroforestry practices) and adjacent natural forests are conserving several woody species diversity in its system.

关键词： Agroforestry Conservation Diversity Practice woody species

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Global multifaceted biodiversity patterns,centers,and conservation needs in angiosperms

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Science China(Life Sciences) 2024年第4期67卷 817-828页

作者： Ao Luo Yaoqi Li Nawal Shrestha Xiaoting Xu Xiangyan Su Yichao Li Tong Lyu Kilara Waris Zhiyao Tang Xiaojuan Liu Luxiang Lin Yongsheng Chen Kuiling Zu Wenqi Song Shijia Peng Niklaus E.Zimmermann Loïc Pellissier Zhiheng Wang Institute of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of Education College of Urban and Environmental SciencesPeking UniversityBeijing 100871China Department of Health and Environmental Sciences Xi’an Jiaotong-Liverpool UniversitySuzhou 215123China State Key Laboratory of Grassland Agro-Ecosystems College of EcologyLanzhou UniversityLanzhou 730000China Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education College of Life SciencesSichuan UniversityChengdu 610065China Land Consolidation and Rehabilitation Center Ministry of Natural ResourcesBeijing 100035China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesKunming 650201China Swiss Federal Research Institute WSL Birmensdorf 8903Switzerland Department of Environmental Systems Science ETH ZürichZürich 8092Switzerland

The Convention on Biological Diversity seeks to conserve at least 30%of global land and water areas by 2030,which is a challenge but also an opportunity to better preserve biodiversity,including flowering plants(angiosperms).Herein,we compiled a large database on distributions of over 300,000 angiosperm species and the key functional traits of 67,024 *** this database,we constructed biodiversity-environment models to predict global patterns of taxonomic,phylogenetic,and functional diversity in terrestrial angiosperms and provide a comprehensive mapping of the three diversity *** further evaluated the current protection status of the biodiversity centers of these diversity *** results showed that geographical patterns of the three facets of plant diversity exhibited substantial spatial mismatches and nonoverlapping conservation *** centers of functional diversity,particularly of herbaceous species,were primarily distributed in temperate regions and under weaker protection compared with other biodiversity centers of taxonomic and phylogenetic *** global assessment of multifaceted biodiversity patterns and centers highlights the insufficiency and unbalanced conservation among the three diversity facets and the two growth forms(woody ***),thus providing directions for guiding the future conservation of global plant diversity.

关键词： angiosperms species richness phylogenetic diversity functional diversity plant traits woody species herbaceous species

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Diversity and Structure of the woody Stand in a Sudano-Sahelian Transition Zone in Senegal

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Open Journal of Ecology 2024年第1期14卷 1-16页

作者： Oumar Sarr Moustapha B. Sagna Amy Bakhoum Sékouna Diatta Aliou Guissé UCAD/FST Laboratory of Ecology and Ecohydrology Dakar Senegal Tessekere Human Environment Observatory (Senegal) IRL 3189 “Environment Health Society” Dakar Senegal

The main objective of the study was to investigate the diversity of the woody stratum of the vegetation in intercommunity rangelands in the department of Koungheul based on an ecological inventory using vegetation surveys. The results indicate a rich flora of 70 species divided into 54 genera and 27 families where Ceasalpiniaceae and Rubiaceae are dominant (5 genera each). They are followed by Combretaceae and Euphorbiacea (4 genera each) and by Capparaceae, Fabaceae and Mimosaceae (3 genera for each family). But at the specific level, it is the Combretaceae which dominates with 10 species and Rubiaceae (7 species). It is more representative at the level of the rural community of Lour Esacale. The different values of vegetation parameters from one site to another indicate variability in community rangeland management practices. The woody stand, dominated by small Combretaceae, shows a relatively stable level of organization with an average equitability of about 45% for the two rural communities studied. species such as Cordyla pinnata, Sclerocarya birrea, Adansonia digitata and Sterculia setigera contributed strongly to the basal and aerial cover of the overall stand. The regeneration of the stand is very good (about 85% on average) but it represents very few species, especially of the Combretaceae family. This shows a tendency to a progressive loss of species richness in the woody stratum.

关键词： Flora woody species Vegetation Surveys Regeneration Kaffrine Region

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Qualitative and Quantitative Characterization of Wood Fibers of Shrubs and Tree species of the Tamaulipan Thorn Scrub, Northeastern Mexico and Its Possible Relation to Wood Quality and Utilization

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American Journal of Plant Sciences 2016年第7期7卷 1046-1057页

作者： Ratikanta Maiti Humberto G. Rodriguez Aruna Kumari Departamento de Quimica y Biologia Universidad de las Americas Santa Catarina Martir Mexico Facultad de CienciasForestales Universidad Autonoma de Nuevo Leon Linares Mexico Agricultural College Jaya Shankar Telangana State Agricultural University Jagtial India

The present study was undertaken to determine the variability in fiber cell morphology and its length among wood species of the Tamaulipan Thorn Scrub, Northeastern Mexico, used for various uses such as timber for furniture, fence, post, firewood and sources of forage. The results reveal large variability in fiber cell morphology and fiber cell dimensions. The species are classified on the basis of its fiber cell morphology and fiber cell length and recommended for their possible utilization for different purposes. Wood having fibre cells with broad lumen and thin wall could be suitable for the manufacture of paper documented in the literature viz. Acacia farnesciana, Caesalpinia mexicana, Cordia boisiieri, Diospyros palmeri, Forestieria angustifolia, Morus celtifolia, Prosopis laevigata. This technique can be used in preliminary screening of woody species for its utilization for different purposes. Further studies are needed to confirm.

关键词： Wood Fiber Cells Characterization Variability woody species Wood Quality Tamualipan Thorn Scrub

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