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Quantifying Arborescent Flora Diversity in a Secondary Forest Ecosystem: A Comprehensive Assessment in Nambalan, Mayantoc, Tarlac, Philippines
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作者 Baby Jean L. Herbulario Raffy L. Tano Mileatte P. Omaney 《Open Journal of Ecology》 2023年第6期387-408,共22页
Forest plays a crucial role in providing essential ecosystem services, including water supply, climate regulation, and biodiversity conservation. This study aimed to assess the current state of the forest in Barangay ... Forest plays a crucial role in providing essential ecosystem services, including water supply, climate regulation, and biodiversity conservation. This study aimed to assess the current state of the forest in Barangay Nambalan, Mayantoc, Tarlac. The specific objectives were to identify tree species in the area and determine the tree diversity index, with a focus on endemism and conservation status. Two transect lines, each spanning one kilometer, were established and a total of 10 sampling quadrats were surveyed. Ecological parameters (relative frequency, relative density, relative dominance, and importance value index) and diversity indices (Shannon-Weiner index, Simpson’s index) were computed using the Paleontological Statistic Software Package for Educational Analysis (PAST 4.03). A comprehensive inventory revealed a total of 756 individuals representing 52 species, 46 genera, and 25 families. Among the recorded species, 10 (17.2%) were endemic and 11 (21.6%) were classified as threatened. The Fabaceae (20.8%), Moraceae (14.6%), and Euphorbiaceae (8.3%) were identified as the most abundant families. The computed diversity indices indicated that Barangay Nambalan retains a diverse forest cover;however, species composition was found to be relatively low. Based on the finding, this study recommends the strict enforcement of protective measures and legislation to mitigate further degradation of the remaining forest in Barangay Nambalan. 展开更多
关键词 Forest diversity Tree Species ENDEMISM Conservation Status Transect Survey diversity Indices
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Phylogeny Constructed by Using Diversity Increment 被引量:1
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作者 Shi Feng, Li Na-na, Li Yuan-xiang, Zhou Huai-beiSchool of Mathematics and Statistics, Wuhan University, Wuhan 430072,Hubei,ChinaAdvanced Research Center for Science and Technology, Wuhan University, Wuhan 430072, Hubei,ChinaState Key Laboratory of Software Engineering, Wuhan University, Wuhan 430072,Hubei,China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第S1期303-306,共4页
A new approach based on the concept of the diversity increment is applied to reconstruct a phylogeny. The phylogeny of the Eutherian orders use concatenated H-stran-ded amino acid sequences, and the result is consiste... A new approach based on the concept of the diversity increment is applied to reconstruct a phylogeny. The phylogeny of the Eutherian orders use concatenated H-stran-ded amino acid sequences, and the result is consistent with the commonly accepted one for the Eutherians. 展开更多
关键词 diversity indicator PHYLOGENY DISTANCE
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Relationship of species diversity between overstory trees and understory herbs along the environmental gradients in the Tianshan Wild Fruit Forests, Northwest China 被引量:1
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作者 CHENG Junhui SHI Xiaojun +3 位作者 FAN Pengrui ZHOU Xiaobing SHENG Jiandong ZHANG Yuanming 《Journal of Arid Land》 SCIE CSCD 2020年第4期618-629,共12页
In forest ecosystems, interactions between overstory trees and understory herbs play an important role in driving plant species diversity. However, reported links between overstory tree and understory herb species div... In forest ecosystems, interactions between overstory trees and understory herbs play an important role in driving plant species diversity. However, reported links between overstory tree and understory herb species diversity have been inconsistent, due to variations in forest types and environmental conditions. Here, we measured species richness(SR) and diversity(Shannon-Wiener(H') and Simpson's(D) indices) of overstory trees and understory herbs in the protected Tianshan Wild Fruit Forest(TWFF), Northwest China, to explore their relationships along the latitudinal, longitudinal, elevational, and climatic(current climate and paleoclimate) gradients in 2018. We found that SR, and H' and D diversity indices of overstory trees and understory herbs exhibited a unimodal pattern with increasing latitude and elevation(P<0.05) and negative associations with longitude(P<0.01). Along the climatic gradients, there were U-shaped patterns in SR, and H' and D diversity indices between trees and herbs(P<0.05). SR, and H' and D diversity indices for overstory tree species were positively associated with those for understory herbs(P<0.01). These findings indicate that overstory trees and understory herbs should be protected concurrently in the TWFF to increase effectiveness of species diversity conservation programs. 展开更多
关键词 diversity indices overstory trees understory herbs PALEOCLIMATE current climate elevation
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Impact of Removal of Copper Leaf (<i>Acalypha fruticosa</i>Forssk.) on Plant Species Diversity and Abundance at Chemeron, Baringo County, Kenya 被引量:1
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作者 George Morara Ogendi Rhoda N. Ondieki Tabitha W. Njoroge 《Open Journal of Ecology》 2020年第6期341-355,共15页
Invasive plant species may significantly alter plant species community composition and structure thereby negatively impacting on ecosystem services. Their impacts on plant communities may be both direct and indirect. ... Invasive plant species may significantly alter plant species community composition and structure thereby negatively impacting on ecosystem services. Their impacts on plant communities may be both direct and indirect. The direct effects may include a reduction in the abundance and diversity of palatable plant species that constitute important forage for livestock, wildlife, and medicines for the local communities. Declines in ecosystem resilience are of the notable indirect effects of invasive species. The aim of this study was to assess the impacts of a plant species, copper leaf (<em>Acalypha fruticosa</em>) on floral diversity and abundance at Chemeron, Baringo County in Kenya. The study was guided by three questions: What is the plant composition in terms of grasses, herbs, shrubs, and trees in the study area? Are there any variations in plant abundance between the two sites (sites with and without <em>Acalypha fruticosa</em>)? Are there variations in plant species diversity between the two study sites? Two sites (one with <em>A. fruticosa</em> and another two without this invasive species) were selected within the Chemeron Research Centre. Two belt transects measuring 100 m × 20 m on each site were laid parallel to each other. Plant samples were collected from five 1 m × 1 m quadrats that were laid at intervals of 20 m. The plant species or specimens were identified to the species level using available taxonomic keys. Various indices including Shannon-Wiener (<em>H</em>’), Evenness Index, Richness Index and Simpson’s Index of Diversity Index (SDI) were calculated. All the diversity, richness and evenness indices were considerably higher in the site without <em>A. fruticosa</em> compared to that where this invasive species was present. Higher <em>H’</em> (3.14 to 3.21) and SDI (0.93 to 0.94) values were noted in sites without the invasive species compared to <em>H</em>’ (2.11 to 2.20) and SDI (0.77 to 0.85) in sites with <em>A. fruticosa</em> present. Out of the 47 plant species identified, 39 and 20 of them occurred in the site without and with <em>A. fruticosa</em>, respectively. Further, there were more grasses (<em>Aristida keniensis</em>, <em>Cynodon dactylon</em>, <em>Brachiaria lucrantha</em>, <em>Eragrostis racemosa</em>, and <em>Enteropogon macrostachyus</em>) in the site without <em>A. fruticosa</em> compared to that with the invasive plant. The plants were also more evenly distributed in the site without <em>A. fruticosa</em> compared to that where the invasive plant was present. We conclude that <em>A. fruticosa</em> has a significant effect on plant species abundance and diversity as well as distribution. Its removal created a favourable environment for the growth of a variety of grasses. We therefore recommend to the agro-pastoralists and rangeland managers that <em>A. fruticosa</em> be mechanically removed by uprooting from grazing lands so as to increase forage availability and quality in the rangelands of South-Baringo. 展开更多
关键词 Baringo Copper Leaf diversity Indices Invasive Species Plant diversity
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Plant diversity at Chilapatta Reserve Forest of Terai Duars in subhumid tropical foothills of Indian Eastern Himalayas
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作者 Gopal Shukla Rajib Biswas +1 位作者 A. P. Das Sumit Chakravarty 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第3期591-596,共6页
From March 2007 to March 2009 we quantified plant diversity at Chilapatta Reserve Forest in Terai Duars in the Indian eastern Himala-yas. We sampled stratified random nested quadrats. Species richness was 311, represe... From March 2007 to March 2009 we quantified plant diversity at Chilapatta Reserve Forest in Terai Duars in the Indian eastern Himala-yas. We sampled stratified random nested quadrats. Species richness was 311, representing 167 genera and 81 families. The species diversity index and concentration of dominance of the forest were 2.20 and 0.0072, respectively. Shannon-Wiener index and evenness indices were 4.77 and 1.44, respectively. The Importance Value Index (IVI) of species ranged from 0.13 to 37.94. The estimated diversity indices indicated heterogene-ity of the forest in its composition, structure, function and dynamics. Rich forest plant diversity supports the need for continued conservation of tropical forests. 展开更多
关键词 Terai Duars phyto-sociology plant diversity diversity indices
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Mycoendophytic diversity and their antimicrobial potential from two epiphytic orchids of the Western Ghats forests of India
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作者 Nuthan BR Rakshith D +4 位作者 Marulasiddaswamy KM Ramesha KP Chandra Mohana N Sampath Kumara KK Satish S 《Studies in Fungi》 2020年第1期113-124,共12页
The epiphytic plants belong to a group that harmlessly grows on other plants by utilizing the nutrition from the host plants with their unique adaptation features along with symbiotic associations with fungi or bacter... The epiphytic plants belong to a group that harmlessly grows on other plants by utilizing the nutrition from the host plants with their unique adaptation features along with symbiotic associations with fungi or bacteria.The various biological activities exhibited by the mycoendophytes inhabiting medicinally-important epiphytic orchids serve as the primary source of novel drug leads,industrially-essential enzymes,and plant growth-promoting metabolites.In the present study,a total of 956 culturable mycoendophytes out of 1600 segments belonging to 17 genera were isolated from different tissue parts of Trias stocksii and Dendrobium herbaceum.The Xylariaceae taxa were the predominant mycoendophytes present in both plants,followed by Pestalotiopsis sp.,Colletotrichum sp.,and Fusarium sp.An estimation of the Shannon-Wiener and Simpson diversity indices showed that the bulbs of T.stocksii have the highest species diversity index and the stems of D.herbaceum the lowest.The highest species richness was observed in the leaves of T.stocksii and the lowest in the leaves of D.herbaceum.Overall,T.stocksii harbored more mycoendophytes along with the highest diversity indices compared to D.herbaceum.The antimicrobial evaluation revealed that Xylaria sp.has a higher potential of producing anti-infectives and opens a new arena for industrial exploration. 展开更多
关键词 Antimicrobial activity Dendrobium herbaceum diversity indices Mycoendophytes Trias stocksii Xylaria sp
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Butterfly Diversity in Relation to Human-Impact Gradient in Out-skirts of Kolkata,West Bengal,India
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作者 Kaiyum Baskh Mollah Sudipta Mandal 《Research in Ecology》 2022年第4期1-12,共12页
Anthropogenic activities may affect species diversity and community structure.Butterfly species diversity in relation to human-impact gradient was evaluated in the Baruipur subdivision,outskirts of Kolkata metropolis,... Anthropogenic activities may affect species diversity and community structure.Butterfly species diversity in relation to human-impact gradient was evaluated in the Baruipur subdivision,outskirts of Kolkata metropolis,West Bengal,India as a model geographic area.Four study sites situated in bird sanctuaries,rural,suburban and urban areas with different levels of anthropogenic disturbances were selected to assess the human impact on butterfly diversity.A total of 80 butterfly species were recorded during the entire study period with the sanctuary(with minimal anthropogenic disturbance)showing the highest species richness(73)followed by rural(62),suburban(54)and urban(36)study sites indicating a strong negative impact of anthropogenic disturbance on butterfly species diversity.Butterfly species diversity varied significantly among different habitats(p˂0.001).The relative abundance of butterflies also varied seasonally.It is apparent that the area under the present study is able to sustain diverse butterfly species provided natural habitats are protected from anthropogenic disturbances and steps are taken to increase urban greenery to support butterfly diversity and consequent ecosystem services. 展开更多
关键词 Butterfly diversity Human-impact gradient Baruipur subdivision KOLKATA diversity indices
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Endophytic fungal diversity of endemic carnivorous plant Nepenthes khasiana in Meghalaya,India
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作者 Naseem F Kayang H 《Studies in Fungi》 2021年第1期138-150,共13页
The present investigation deals with the isolation of endophytic fungi from leaf,stem,root and pitcher cup tissue segments of the endemic carnivorous plant Nepenthes khaisana collected from its natural habitat for a p... The present investigation deals with the isolation of endophytic fungi from leaf,stem,root and pitcher cup tissue segments of the endemic carnivorous plant Nepenthes khaisana collected from its natural habitat for a period of one year at monthly intervals.Out of 576 tissue segments inoculated,a total of 39 fungal endophytes along with mycelia sterilia were isolated from the host plant.To assess the diversity of fungal endophytes,the colonization frequency(%CF)was first recorded using past software and MS excel.The fungal isolates were mainly composed of the phylum Ascomycota,followed by Zygomycota and Oomycota.The highest percentage colonization frequency on an average of three replicates were recorded in pitcher cup tissues followed by root,stem and least was recorded in leaf of the host plant.Among the isolates,Globisporangium irregulare(83.33%)showed high%CF in leaf,Juxtiphoma eupyrena(83.33%)reported to have maximum%CF in the stem,Talaromyces ruber(66.66%)was recorded high%CF in root and mycelia sterilia(white)were showed the highest%CF in the segments of leaf.The diversity index analyses of Shannon-Weiner,Simpson’s index,species richness and species evenness of diversity showed that leaf of N.Khasiana has the highest diversity than the other parts of the plant.So,with the help of the present finding,we conclude that the distribution of fungal endophytes and their%colonization frequencies vary within different tissues of the host plant and thus,this confirms tissue specificity nature of endophytic fungi. 展开更多
关键词 Colonization frequency diversity indices Natural habitat Pitcher plant Tissue specificity
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Evaluation of Plant Diversity for Sustainable and Inclusive Management in Rural Areas:A Case Study from Daressalam,Niger
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作者 Inoussa Maman Maarouhi Ibrahim Fataw 《Research in Ecology》 2022年第1期37-43,共7页
Plant biodiversity plays a major role for sustaining livelihood of rural population.However,unsustainable exploitation of woody plants for firewood in Niger is creating ecological challenges.This study aims to evaluat... Plant biodiversity plays a major role for sustaining livelihood of rural population.However,unsustainable exploitation of woody plants for firewood in Niger is creating ecological challenges.This study aims to evaluate plant species composition,richness and equitability for sustainable and inclusive management in rural areas.Plot vegetation inventory method was employed.Forty-eight plots each measuring 2500 m^(2)were laid down systematically on a transect with the village at the centre.On each plot,plant species were identified and the number of each species counted.A total of twenty-five(25)plant species belonging to thirteen(13)families were identified among which Guiera senegalensis J.F.Gmel.accounted for 61%.The Shannon index was low(H’=0.45)as well as species equitability(E=0.14).Species richness differed significantly(p<0.000)with land use type with agroforestry parklands recording significantly higher species compared to plateaus.For effective plant biodiversity restoration and management,irrigated agroforestry is recommended to restore ecological balance and to assure and improve the quality of plant biodiversity in the study area. 展开更多
关键词 Guiera senegalensis diversity indices Sustainable and inclusive management Land use
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Estimation of carbon pools in secondary tropical deciduous forests of Odisha,India
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作者 Subhashree Pattnayak M.Kumar +1 位作者 N.K.Dhal Sudam C.Sahu 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第2期663-673,共11页
Secondary tropical forests sequester atmospheric CO 2 at relatively faster rates in vegetation and in soil than old-growth primary forests.Spatial understanding of biomass and carbon stocks in different plant function... Secondary tropical forests sequester atmospheric CO 2 at relatively faster rates in vegetation and in soil than old-growth primary forests.Spatial understanding of biomass and carbon stocks in different plant functional types of these forests is important.Structure,diversity,composition,soil features and carbon stocks in six distinct plant functional types,namely:Moist Mixed-Deciduous Forest,Peninsular Sal Forest(PSF),Semi-Evergreen Forest(SEF),Planted Teak Forest,Bamboo Brakes(BB),and Degraded Thorny Shrubby Forest were quantified as secondary tropical deciduous forests of the Chandaka Wildlife Sanctuary,Eastern Ghats of Odisha,India.Seventy-one species≥10 cm Girth at breast height(GBH)were recorded,belonging to 38 families and 65 genera.Above-ground biomass carbon and soil organic carbon ranged from 2.1–72.7 Mg C ha^(−1) and 20.6–67.1 Mg C ha^(−1),respectively,among all plant functional types.Soil organic carbon and important value index were positively correlated with above-ground biomass carbon.Maximum carbon allocation was in SOC pool(51–91%),followed by the above-ground biomass pool(9–52%),indicating SOC is one of the major carbon sinks in secondary dry forests.The results highlight the importance of secondary tropical deciduous forests in biodiversity conservation and ecological importance in reducing greenhouse gases. 展开更多
关键词 Chandaka wildlife Sanctuary diversity indices Soil organic carbon Above-ground biomass carbon Correlation study
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Is urban development an urban river killer? A case study of Yongding Diversion Channel in Beijing, China 被引量:8
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作者 Xi Wang Junqi Li +4 位作者 Yingxia Li Zhenyao Shen Xuan Wang Zhifeng Yang Inchio Lou 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第6期1232-1237,共6页
The high population and concrete environment alter urban areas by changing temperature, rainfall runoff, and water resource utilization activities. This study was conducted to investigate the water quality features of... The high population and concrete environment alter urban areas by changing temperature, rainfall runoff, and water resource utilization activities. This study was conducted to investigate the water quality features of the Yongding Diversion Channel in Beijing, China, and its relationship with rainfall and urban development. Monthly water quality data were obtained from April to October of 2004 at monitoring sites of Sanjiadian, Gaojing, Luodaozhuang, and Yuyuangtan. The monthly water quality grades from 2007 to 2011 were also investigated and compared with those of other rivers. Dissolved oxygen and pH showed greater decreases after one or two moderate rainfall events than several light rainfall events. The potassium permanganate index (CODMn), ammonia nitrogen (NH3-N) and total phosphorus (TP) increased more after several light rainfall events than after one or two moderate or heavy rainfall events. Pollutant concentrations (CODMn, NH3-N, TP) in downstream regions showed greater changes than those in upstream areas after heavy rainfall events. Intense human activities around the channel greatly influenced the water quality of the channel in rainy season because of runoff pollution; however, heavy rainfall had a strong dilution effect on the pollutant concentrations in rivers. Overall, urban development has obviously deteriorated the water quality of the Yongding Diversion Channel as indicated by an increase in the water quality index from 3.22 in 2008 to 4.55 in 2010. The Pearson correlation between monthly rainfall and water quality indices from 2007 to 2011 ranged from 0.1286 to 0.6968, generally becoming weaker as rainfall and rainfall runoff became more random and extreme. 展开更多
关键词 rainfallurban development water quality indices Yongding Diversion Channel
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