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Species Richness, Diversity and Density of Understory Vegetation along Disturbance Gradients in the Himalayan Conifer Forest 被引量:2
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作者 Kesang WANGCHUK András DARABANT +3 位作者 Prem Bahadur RAI Maria WURZINGER Werner ZOLLITSCH Georg GRATZER 《Journal of Mountain Science》 SCIE CSCD 2014年第5期1182-1191,共10页
We investigated whether species richness, diversity and density of understory herbaceous plants differed along logging(gap) and grazing(primarily by cattle) disturbance gradients, and sought to identify drivers of ric... We investigated whether species richness, diversity and density of understory herbaceous plants differed along logging(gap) and grazing(primarily by cattle) disturbance gradients, and sought to identify drivers of richness, diversity and density of understory vegetation of logged sites. A factorial experiment was conducted in the mixed conifer forest of Gidakom in Western Bhutan. Levels of the logging treatment included small(0.15 – 0.24 ha), medium(0.25 – 0.35 ha) and large(0.36 – 1.31 ha) gaps. The grazing treatment included grazed(primarily by cattle) and ungrazed(where herbivores were excluded by a fence) plots nested within each gap. Data were collected from 12 gaps(4 replicates at each level of logging) using the point intercept method. Shannon Weaver Diversity and Margalef's indices were used to estimate species diversity and describe species richness, respectively. Soil samples were analyzed for pH and nutrients. The interaction effect of logging and grazing was significant(p≤0.001) only on species diversity. Relative to ungrazed areas, species diversity was significantly higher(0.01≤p≤0.05) in medium grazed gaps. Under grazed conditions, soil P was negatively correlated with gap size and species diversity. While species diversity was positivelycorrelated(0.01≤p≤0.05) with soil N in grazed plots species richness was positively correlated(0.001≤p≤0.01) with soil N in ungrazed plots. Relative density of Yushania microphylla and Carex nubigena were higher under ungrazed conditions. Our study suggests that the combined effect of cattle grazing and logging results in higher species diversity of understory vegetation in medium and grazed gaps in mixed conifer forests of Bhutan,whereas increase or decrease in relative density of major species is determined primarily by the independent effects of grazing and logging. From management perspective, forest managers must refrain from creating large gaps to avoid loss of nutrients(mainly P and N), which may eventually affect tree regeneration. Managers intending to maintain understory vegetation diversity must consider the combined effects of grazing and logging, ensuring low to moderate grazing pressure. 展开更多
关键词 物种多样性 相对密度 林下植被 干扰梯度 针叶林 喜马拉雅 品种 物种丰富度
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Neighborhood diversity structure and neighborhood species richness effects differ across life stages in a subtropical natural secondary forest 被引量:1
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作者 Haonan Zhang Shuifei Chen +5 位作者 Xiao Zheng Xiaomin Ge Yao Li Yanming Fang Peng Cui Hui Ding 《Forest Ecosystems》 SCIE CSCD 2022年第6期790-801,共12页
Natural secondary forest has a strong capacity to regrow naturally and recover biodiversity rapidly on abandoned lands.However,at the neighborhood scale,which can truly reflect the facilitative or competitive interact... Natural secondary forest has a strong capacity to regrow naturally and recover biodiversity rapidly on abandoned lands.However,at the neighborhood scale,which can truly reflect the facilitative or competitive interactions among individual plants,the local diversity spatial structure in secondary forest and the feedback effects of neighborhood diversity on natural regeneration remain unclear,and this may be the key to properly understand the mechanisms of natural secondary forest species diversity recovery.To this end,this study established a dynamic plot in a rehabilitated secondary forest after disturbance and conducted a comprehensive survey of 68,336 individual plants with repeated measurements at 5-year interval to assess the characteristics of neighborhood diversity structure across life history stages and link the neighborhood species richness(NSR)effect translated by species interactions at species diversity structure with individual trees recruitment/mortality in secondary forest regeneration.The results showed that,compared with tropical and temperate natural forests,a higher proportion of diversity accumulators and a lower proportion of repellers in subtropical secondary forests resulted in neighborhood diversity structures characterized by heterospecific or high-diversity patches,which are beneficial to the maintenance or restoration of biodiversity.As an important supplement to the research on the relationship between diversity and productivity,our findings show a positive diversity-survival relationship in subtropical secondary forests.Importantly,we observed that the neighborhood diversity structure exhibited a trend of accumulator-dominated to neutral-dominant changes with life stage from sapling to adult,which,in turn,determined the direction and strength of NSR effects on recruitment/mortality.Specifically,diverse local neighborhoods at a later successional stage characterized with‘neutral’species-species interactions can act as a‘welfare net’by offering favorable microhabitats for the most vulnerable recruitments or saplings,i.e.,the NSR effects that promoted individual recruitment/survival in our study.These results not only enrich our understanding of the biodiversity-productivity-survival relationship but also highlight the importance of retaining latesuccessional species of native trees in intensive forest production or in situ conservation policies. 展开更多
关键词 Secondary forest restoration Individual species area relationship diversity accumulator species Neighborhood species richness effect Life history stages Heterospecific crowding
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Diversity and structural composition of species in dipterocarp forests:a study from Fasiakhali Wildlife Sanctuary, Bangladesh 被引量:3
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作者 S.C.Das M.S.Alam M.A.Hossain 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第5期1241-1249,共9页
Fasiakhali Wildlife Sanctuary is a protected area composed of tropical remnant rainforest that harbor substantial number of large,old Garjan(Dipterocarpus spp.)trees.The present study assessed composition,structure ... Fasiakhali Wildlife Sanctuary is a protected area composed of tropical remnant rainforest that harbor substantial number of large,old Garjan(Dipterocarpus spp.)trees.The present study assessed composition,structure and diversity of the species in this protected area.A total of 32 trees species were recorded with DBH ≥ 11 cm belonging to 24 genera and 19 families.The forest is low in plant diversity as represented by Shannon–Wiener diversity and Simpson Dominance indices.Dipterocarpus turbinatus was the most dominant species with maximum relative density,frequency,dominance,and importance value index.Syzygium firmum and Tectona grandis followed in terms of dominance.The structural composition indicated higher number of individuals in the medium growth classes(41 to 〈 511 cm DBH and 16–20 m height ranges),whereas D.turbinatus was the only species that dominated most of the growth classes.Poor stem density in lower growth classes indicated meager recruitment of regeneration which may be due to lower annual precipitation,increased grazing and encroachments.This study will help to understand the patterns of tree species composition and diversity in the remnant dipterocarp forests of Bangladesh.It will also contribute to identifying threatened plants to undertake D.turbinatus based conservation and sustainable management of the Fasiakhali Wildlife Sanctuary. 展开更多
关键词 species diversity Structural composition Protected area Importance value index Cluster analysis
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Relationship between diversity of forest plant species and environmental gradient in eastern mountainous area of Heilongjiang Province, China 被引量:2
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作者 WANG Qing-gui XING Ya-juan +1 位作者 ZHOU Xiao-feng HAN Shi-jie 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第3期252-254,共3页
Twenty-three secondary forest communities with different structure were selected in Mao'er Mountain National Park of Heilongjiang Province, China to study the relationship between diversity of forest plant species an... Twenty-three secondary forest communities with different structure were selected in Mao'er Mountain National Park of Heilongjiang Province, China to study the relationship between diversity of forest plant species and environmental gradient. The forest plant species diversity was analyzed by the diversity index, and the environmental factors was quantified by the method of Whittaker's quantification of environmental gradient. Meanwhile, β-diversity indexes of communities were calculated with similar measurements. The results showed that the Shannon-wiener diversity index of forest plant species increased with the increase of the environmental gradient, and the β-diversity indexes of communities showed a liner increase along with the change of environmental gradient. 展开更多
关键词 species diversity forest plant species Heilongjiang Province Shannon-wiener diversity β-diversity index Environmental gradient
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Species Diversity Based on Vertical Structure as Indicators of Artificial Restoration for Coniferous Forests in Southwest China 被引量:1
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作者 ZHANG Qiaoying ZHANG Yunchun +3 位作者 Eshetu Yirdaw LUO Peng YI Shaoliang Wu Ning 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期1003-1008,共6页
Five indices of species richness, species diversity and species evenness were used to assess a diversity of four types of coniferous forests undergone different artificial regeneration time. The study was based on the... Five indices of species richness, species diversity and species evenness were used to assess a diversity of four types of coniferous forests undergone different artificial regeneration time. The study was based on the vertical structure of forests, involving growth-forms of total plants as well as vertical layers of woody plants. The results showed that, except for the fourth layer of woody plants, the vertical structure of the four forests exhibited significant difference in terms of their species richness, species diversity and species evenness, suggesting that a species diversity index provided more detailed information and was a better index reflecting the regeneration processes in this region. It was recommended that silvicultural management of artificially regenerated forests should be strengthened to conserve the biodiversity of the forests, optimize forest structure and, in the long run, promote sustainable development of forest ecosystems. 展开更多
关键词 species richness species diversity species evenness forest management sub-alpine coniferous forests
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Effect of environmental factors on species diversity of the Yenice Hot Spot Forests in Turkey 被引量:1
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作者 Sevda Turkis Emire Elmas 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第6期1719-1730,共12页
We quantified the diversity of vascular plant species and described soil properties and topographical and climatic conditions of the Citdere and Kavakli Nature Reserves in the Yenice Forest of Turkey. We used the Shan... We quantified the diversity of vascular plant species and described soil properties and topographical and climatic conditions of the Citdere and Kavakli Nature Reserves in the Yenice Forest of Turkey. We used the Shannon-Weiner and Simpson's indices of diversity,Margalef's index of species richness and Pielou's evenness index to quantify the structure of vascular plant assemblages. We measured soil parameters(NO_3^-, NH_4^+,available P, Mg^(++), K^+, Na^+, Ca^(++), organic matter, pH,soil moisture), elevation, slope gradient and aspect and their correlations with plant community parameters. In total, we recorded and identified 207 species and subspecies in the study area. Species cover, richness and diversity indices varied significantly by vegetation type(P < 0.01). Available NO_3^- and Ca++ in the soil were important factors for the area and species representation in the species-environment correlations estimated for the Kavakli area. Available NO_3^-,pH, organic matter, Ca^(++) and K^+ in the soil were important factors for the area and species representation in the species-environment correlations analysed for the Citdere area. 展开更多
关键词 diversity forest ecosystems Yenice hotspot species richness
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Composition, diversity and distribution of tree species in response to changing soil properties with increasing distance from water source – a case study of Gobind Sagar Reservoir in India 被引量:3
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作者 Somanath SARVADE Bhupender GUPTA Matber SINGH 《Journal of Mountain Science》 SCIE CSCD 2016年第3期522-533,共12页
Construction of big dams on rivers develops artificial lakes or water reservoirs which conceive alterations in soil properties of the upstream catchment area. An undulating topography and freckly soil properties cause... Construction of big dams on rivers develops artificial lakes or water reservoirs which conceive alterations in soil properties of the upstream catchment area. An undulating topography and freckly soil properties cause ups and downs in tree diversity, composition and distribution. The study aimed to evaluate the effect of Gobind Sagar reservoir on soil properties relative to the distance from it and assess its effect on tree diversity, evenness and their distribution in tropical and subtropical forests. Based on data analysis it was found that the soil moisture and organic carbon decreased along with increasing distance from the reservoir. It played a significant role in varying tree diversity. The sites distributed within0-2 km showed significantly higher α and β-diversity indices. Tree species richness and diversity indices showed a strong correlation(p < 0.05) with soil moisture and organic carbon content. Simpson's and Mc Intosh evenness indices showed a strong negative correlation with soil bulk density. Indirect Detrended Correspondence Analysis(DCA) identified soil moisture and soil organic carbon as two major environmental gradients that influenced tree diversity and their distribution in five tropical and four subtropical forests in an upstream catchment of the reservoir. Mixed forests inhabited moist sites andAcacia-Pinus forests showed an inclination to dry areas. Canonical Correspondence Analysis(CCA)revealed that the tree species in tropical forests were mainly affected by driving forces such as soil moisture,organic carbon and bulk density whereas, in subtropical forest tree species were influenced by elevation, soil p H, EC and clay content. 展开更多
关键词 物种多样性 土壤性质 水库 距离 组成 亚热带森林 除趋势对应分析 树种多样性
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Isolation and species diversity of arbuscular mycorrhizal fungi in the rhizosphere of Puccinellia tenuiflora of Songnen saline-alkaline grassland,China
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作者 YUNHUI ZHOU YAJIE LIU +3 位作者 WENNA ZHAO FEI CHEN YUDAN WANG CHUNXUE YANG 《BIOCELL》 SCIE 2022年第11期2465-2474,共10页
Salinization has led to the deterioration of the ecological environment,affected the growth of plants,and hindered the development of agriculture and forestry.Arbuscular mycorrhizal(AM)fungi,as important soil microorg... Salinization has led to the deterioration of the ecological environment,affected the growth of plants,and hindered the development of agriculture and forestry.Arbuscular mycorrhizal(AM)fungi,as important soil microorganisms,play significant physiological and ecological roles in promoting plant nutrient absorption and improving soil structure.Puccinellia tenuiflora(Turcz.)Scribn.et Merr.in Songnen saline-alkaline grassland was selected as the research object to observe AM fungal colonization of the roots and explore the species and diversity of AM fungi in symbiotic association with P.tenuiflora.This study showed that AM fungi colonized in P.tenuiflora roots and formed a typical Arum-type mycorrhizal structure.A significant correlation was observed between vesicular abundance and the colonization intensity of mycorrhiza.Isolation and identification revealed 40 species of AM fungi in the rhizosphere of P.tenuiflora,belonging to 14 genera,of which two species could not be identified.The richness of the genus Glomus was the highest,accounting for 30%of the total species.Funneliformis mosseae and Rhizophagus intraradices were isolated from all the samples and were the species with the widest distribution in the rhizosphere of P.tenuiflora.Correlation analysis showed that pH only had a significant impact on the distribution of a few species,such as Glomus pustulatum,Diversispora spurca,Glomus aggregatum,Rhizophagus clarum,and Acaulospora foveata.The present study provides a theoretical basis for further exploring the resources of AM fungi in saline-alkaline soil. 展开更多
关键词 Morphological identification Spore density species richness diversity indexes Colonization intensity
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Elevational changes in vascular plants richness, diversity, and distribution pattern in Abune Yosef mountain range, Northern Ethiopia 被引量:5
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作者 Kflay Gebrehiwot Sebsebe Demissew +3 位作者 Zerihun Woldu Mekbib Fekadu Temesgen Desalegn Ermias Teferi 《Plant Diversity》 SCIE CAS CSCD 2019年第4期220-228,共9页
The aim of this research is to investigate the patterns of vascular plant species richness,diversity,and distribution along an elevation gradient in the Abune Yosef mountain range,Ethiopia.Preferential systematic samp... The aim of this research is to investigate the patterns of vascular plant species richness,diversity,and distribution along an elevation gradient in the Abune Yosef mountain range,Ethiopia.Preferential systematic sampling was employed to collect vegetation and environmental data along the elevation gradient.We found that plant species richness declines monotonically from low to high elevations.Specifically,vascular plant species richness and diversity were lower in the Afroalpine grassland(high elevation)than in the Dry evergreen Afromontane forest and Ericaceous forest(low elevations).In contrast,endemic vascular plant richness was significantly higher in the Afroalpine grassland than in the Dry evergreen Afromontane forest and Ericaceous forest.Elevation showed a significant impact on the richness,diversity,and endemism of vascular plants.According to Sorensen's coefficient,the similarity between Dry evergreen Afromontane forest and Ericaceous forest vegetation types is higher(32%)than the similarity between Ericaceous forest and Afroalpine grassland(18%).Only 5%similarity was recorded between the Dry evergreen Afromontane forest and Afroalpine grassland.Growth forms showed different elevationai richness patterns.Trees and liana increased monotonically up to 3300 m.Shrub and herb richness patterns followed a hump-shaped and inverted hump-shaped pattern along the elevation gradient.The elevation patterns of vascular plant species richness,diversity,and growth form in the present study may be attributed to differences in management intensity,spatial heterogeneity,microclimatic variations,and anthropogenic disturbances. 展开更多
关键词 Afroalpine CHURCH forest diversity ELEVATION GRADIENT Plant community species richness
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Composition, structure and diversity characterization of dry tropical forest of Chhattisgarh using satellite data 被引量:3
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作者 Tarun Thakur S.L. Swamy Ajit Singh Nain 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第4期819-825,共7页
The purpose of this study was to characterize the land use, vegetation structure, and diversity in the Barnowpara Sanctuary, Raipur district, Chhattisgarh, India through the use of satellite remote sensing and GIS. La... The purpose of this study was to characterize the land use, vegetation structure, and diversity in the Barnowpara Sanctuary, Raipur district, Chhattisgarh, India through the use of satellite remote sensing and GIS. Land cover and vegetation were spatially analyzed by digitally classifying IRS 1D LISS III satellite data using a maximum likelihood algorithm. Later, the variations in structure and diversity in different forest types and classes were quantified by adopting quadratic sampling proce- dures. Nine land-cover types were delineated: teak forest, dense mixed forest, degraded mixed forest, Sal mixed forest, open mixed forest, young teak plantation, grasslands, agriculture, habitation, and water bodies. The classification accuracy for different land-use classes ranged from 71.23% to 100%. The highest accuracy was observed in water bodies and grass- land, followed by habitation and agriculture, teak forest, degraded mixed forest, and dense mixed forest. The accuracy was lower in open mixed forest, and sal mixed forest. Results revealed that density of different forest types varied from 324 to 733 trees ha-l, basal area from 8.13 to 28.87 m2.ha-1 and number of species from 20 to 40. Similarly, the diversity ranged from 1.36 to 2.98, concentration of dominance from 0.06 to 0.49, species richness from 3.88 to 6.86, and beta diversity from 1.29 to 2.21. The sal mixed forest type recorded the highest basal area, diversity was highest in the dense mixed forest, and the teak forest recorded maximum density, which was poor in degraded mixed forests. The study also showed that Normalized Difference Vegetation Index (NDVI) was strongly cor- related to with the Shannon Index and species richness. 展开更多
关键词 forest Shannon index species richness RS and GIS LANDUSE NDVI
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Evaluation of Broadleaf Tree Diversity at the Basin Scale—In Case of Artificial <i>Chamaecyparis obtusa</i>Forests 被引量:1
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作者 Sayumi Kosaka Yozo Yamada 《Open Journal of Forestry》 2013年第2期62-65,共4页
In recent years, the various functions required of forests, especially the conservation of biodiversity, have been attracting increasing attention in Japan and worldwide. In Japan, 67% of national land is covered by f... In recent years, the various functions required of forests, especially the conservation of biodiversity, have been attracting increasing attention in Japan and worldwide. In Japan, 67% of national land is covered by forest, 41% of which is artificial forest (i.e., plantations). Therefore, forest biodiversity conservation efforts should also target artificial forests. In this paper, we seek to promote sustainable forest management that considers biodiversity conservation by examining indices that can be used by forest managers to evaluate the diversity of broadleaf trees. The result was that evaluation of broadleaf tree diversity in artificial forests at a basin scale was possible by combining several types of indicators. 展开更多
关键词 Artificial forest forestRY Management Basin Scale species diversity index Land Use diversity index
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The Rich-Gini-Simpson quadratic index of biodiversity 被引量:2
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作者 Radu Cornel Guiasu Silviu Guiasu 《Natural Science》 2010年第10期1130-1137,共8页
The Gini-Simpson quadratic index is a classic measure of diversity, widely used by ecologists. As shown recently, however, this index is not suitable for the measurement of beta diversity when the number of species is... The Gini-Simpson quadratic index is a classic measure of diversity, widely used by ecologists. As shown recently, however, this index is not suitable for the measurement of beta diversity when the number of species is very large. The objective of this paper is to introduce the Rich- Gini-Simpson quadratic index which preserves all the qualities of the classic Gini-Simpson index but behaves very well even when the number of species is very large. The additive partitioning of species diversity using the Rich-Gini- Simpson quadratic index and an application from island biogeography are analyzed. 展开更多
关键词 Rich-Gini-Simpson index of species diversity Additive Partitioning of diversity Island BIOGEOGRAPHY BIOdiversity
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Assessment of Tree Diversity and Abundance in Rashad Natural Reserved Forest, South Kordofan, Sudan
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作者 Khalid A E Eisawi Hong He +1 位作者 Tayyab Shaheen Emad H. E. Yasin 《Open Journal of Forestry》 2021年第1期37-46,共10页
This study aims to estimate the tree diversity status of Rashad Forest Reserves in the Rashad locality of the South Kordofan State of Sudan. For data collection, eight sample plots (20 × 20</span><b> ... This study aims to estimate the tree diversity status of Rashad Forest Reserves in the Rashad locality of the South Kordofan State of Sudan. For data collection, eight sample plots (20 × 20</span><b> </b><span style="font-family:Verdana;">m) were taken randomly, and parameters were determined: </span><span style="font-family:Verdana;">trees</span><span style="font-family:Verdana;"> species diversity, composition, relative density, dominance, important value index, and species richness in the Rashad forest reserve. The results show that a total of 237 and 56 tree species, including 22 families, have been identified in the study area. Fabaceae family and species numbers have the highest number of 13 species in 8 genera, followed by Combretaceae with 8 species belonging to 3 different genera, Malvaceae with 5 species belonging to 4 different genera, Apocynaceae with 3 species belonging to 3 different genera. The Arecaceae, Burseraceae, Capparaceae, Euphorbiaceae, Meliaceae, and Rubiaceae families each had two species, and all the other 11 families had one species each. Among the 56 different tree species found within the reserve. The results also indicated that </span><i><span style="font-family:Verdana;">Tamarindus indica</span></i><span style="font-family:Verdana;"> L</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">.</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">Ziziphus </span><span style="font-family:Verdana;">spina</span></i><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">christi</span><span style="font-family:Verdana;"> (L.) Desf. had the highest relative density and dominance of 4.64% and 11% respectively. </span><i><span style="font-family:Verdana;">Adansonia digitata</span></i><span style="font-family:Verdana;"> L</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">.</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Grewia </span><span style="font-family:Verdana;">villosa</span></i><span style="font-family:Verdana;"> Willd, </span><i><span style="font-family:Verdana;">Vepris </span><span style="font-family:Verdana;">nobilis</span></i><span style="font-family:Verdana;"> (Delile) Mziray had density and dominance of 4.80% and 9%.</span><b> </b><span style="font-family:Verdana;">Followed by </span><i><span style="font-family:Verdana;">Anogeissus </span><span style="font-family:Verdana;">leiocarpa</span></i><span style="font-family:Verdana;"> (DC.) Guill. & Perr, </span><i><span style="font-family:Verdana;">Adansonia digitata</span></i><span style="font-family:Verdana;"> L</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">.</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">, </span><i><span style="font-family:Verdana;">Catunaregam </span><span style="font-family:Verdana;">nilotica</span></i><span style="font-family:Verdana;"> (Stapf) Tirveng. (Syn: </span><i><span style="font-family:Verdana;">Xeromphis </span><span style="font-family:Verdana;">nilotica</span></i><span style="font-family:Verdana;"> (Stapf) Keay, </span><i><span style="font-family:Verdana;">Vangueria madagascariensis</span></i><span style="font-family:Verdana;"> J. F. Gmel. with 3.38% and 8%, respectively.</span><b> </b><span style="font-family:Verdana;">Eleven species recorded the least relative dominance of 0.42%.</span><b> </b><span style="font-family:Verdana;">Shannon-Weiner diversity index (H’) value stood at 3.82. And as diversity indices varied with location depending on the species available within an ecological zone, </span><span style="font-family:Verdana;">Rashad</span><span style="font-family:Verdana;"> forest reserve is blessed with a moderate diversity index. 展开更多
关键词 ASSESSMENT Tree species diversity Rashad Natural Reserved forest Relative Density Relative Dominance Importance Value index
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Tree assemblages and diversity patterns in Tropical Juri Forest,Bangladesh
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作者 Swapan Kumar Sarker Muhammad Nur-Un-Nabi +4 位作者 Md.Mohasinul Haque Mahmuda Sharmin Sanjay Saha Sonet Sourav Das Niamjit Das 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第1期159-169,共11页
Juri is a biodiversity-rich primary forest in Bangladesh, which remains ecologically unexplored. We identified tree species and examined the richness, alpha(a)diversity and floristic similarity patterns within the i... Juri is a biodiversity-rich primary forest in Bangladesh, which remains ecologically unexplored. We identified tree species and examined the richness, alpha(a)diversity and floristic similarity patterns within the identified communities. Vegetation and environmental data were sampled in 120(0.04 ha) study plots. Tree communities were delimited by two-way indicator species analysis(TWINSPAN). In total, 78 tree species of 35 families and58 genera were identified. TWINSPAN identified six tree communities: A—Tricalysia singularis; B—Kydia calycina-Castanopsis tribuloides; C—Polyalthia simiarum-Duabanga grandiflora; D—Ficus roxburghii; E—Artocarpus lacucha; F—Artocarpus lacucha. Mean richness, Shannon and Gini-Simpson indices were highest for the Polyalthia simiarum-Duabanga grandiflora community, while Ficus roxburghii showed lowest diversity. Significant differences(p = 0.05) in three diversity indices were recorded between Polyalthia simiarum-Duabanga grandiflora and Ficus roxburghii. Tree compositional similarity was greatest between Kydia calycina-Castanopsis tribuloides and Polyalthia simiarum-Duabanga grandiflora(0.712). 展开更多
关键词 Two-way indicator species analysis(TWINSPAN) richness index Shannon index Gini-Simpson index Tropical forest Conservation
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造林密度对科尔沁沙地奈曼沙区小叶杨防护林林下植被的影响 被引量:1
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作者 郭欣宇 杨光 +3 位作者 陆乃静 李庆原 秦忠 宁岩岩 《水土保持研究》 CSCD 北大核心 2024年第1期199-206,共8页
[目的]探明科尔沁沙地南缘的奈曼旗沙区小叶杨(Populus simonii)防护林造林密度对林下植被的影响,提出适宜植被群落多样性恢复与稳定性发展的造林密度。[方法]以自然恢复状态下,林龄相近的3种典型造林密度类型(867~1022株/hm^(2),1444~1... [目的]探明科尔沁沙地南缘的奈曼旗沙区小叶杨(Populus simonii)防护林造林密度对林下植被的影响,提出适宜植被群落多样性恢复与稳定性发展的造林密度。[方法]以自然恢复状态下,林龄相近的3种典型造林密度类型(867~1022株/hm^(2),1444~1667株/hm^(2),2177~2322株/hm^(2))的小叶杨防护林为研究对象,开展每木检尺、物种组成与多样性、植被群落结构等调查,对野外采集数据进行统计分析。[结果]造林可以显著提高植被恢复与演替速度,造林密度的大小对林下植被多样性与群落稳定有显著影响,随着造林密度的减小,林下草本生物量、物种组成丰富度、物种多样性指数增大,植物恢复程度、群落稳定性上升;造林密度与林下物种多样性指数、物种数量、林下植被盖度、林下草本生物量等植被特征指标均呈现极显著负相关关系(p<0.01)。[结论]当小叶杨防护林造林密度为867~1022株/hm^(2)时,群落与未经开垦的草地样地的群落相似性最高,植被群落演替逐渐向地带性植被发展,与其他造林密度相比更有利于研究区物种多样性与群落恢复发展。 展开更多
关键词 科尔沁沙地 造林密度 人工防护林 林下植被 物种多样性
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大庆市蝶类多样性及其影响因素
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作者 袁改霞 张大川 +4 位作者 张国发 殷亚杰 张奕婷 李玥 徐太海 《草业科学》 CAS CSCD 北大核心 2024年第4期845-855,共11页
为明确大庆市蝶类多样性及其影响因素,2016-2019年利用样线法对大庆市不同生境类型中的蝴蝶开展了调查研究。共观测到蝴蝶5780只,隶属6科29属36种。灰蝶科的个体数最多,蛱蝶科的物种数最多,是当地的优势类群;凤蝶科仅1种,是当地的稀有... 为明确大庆市蝶类多样性及其影响因素,2016-2019年利用样线法对大庆市不同生境类型中的蝴蝶开展了调查研究。共观测到蝴蝶5780只,隶属6科29属36种。灰蝶科的个体数最多,蛱蝶科的物种数最多,是当地的优势类群;凤蝶科仅1种,是当地的稀有类群。优势种7个,常见种5个,少见种4个,稀有种20个。不同的生境蝶类群落种类与数量存在一定的差异,人为干扰小、植物群落结构最为复杂的新华草原蝶类的属数和种数最多,而人为干扰较强、植物群落单一的大庆龙凤湿地自然保护区最少;新华草原的蝶类多样性指数最高,大庆龙凤湿地自然保护区最低;新华草原的丰富度指数最高,乘风湖岸边最低。蝶类物种数、个体数、多样性指数及丰富度指数月度变化基本一致,且与月均温显著正相关(P<0.05),而与月降水量无相关性。综上,蝶类多样性与植被类型、月均温有明显的相关性。而相同气象条件下,植被类型是影响蝶类分布的重要因素。为了保护与丰富蝶类资源,建议植被单一的区域,进行适度的植被异质化建设。 展开更多
关键词 蝴蝶 多样性指数 人为干扰 气象因子 月动态 丰富度指数 数量特征
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Old coppice versus high forest:the impact of beech forest management on plant species diversity in central Apennines(italy) 被引量:2
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作者 Andrea Scolastri Laura Cancellieri +1 位作者 Marco Iocchi Maurizio Cutini 《Journal of Plant Ecology》 SCIE CSCD 2017年第2期271-280,共10页
Aims Silvicultural management plays a major role in shaping understory diversity through its action on stand structure.in many parts of Europe,recent socioeconomic changes have led to the progressive abandonment of co... Aims Silvicultural management plays a major role in shaping understory diversity through its action on stand structure.in many parts of Europe,recent socioeconomic changes have led to the progressive abandonment of coppicing in favor of high forest(HF)management.in order to examine how this change impacts understory species,we compared old coppice-with-standards and HF stands in terms of structural features and understory richness and composition,also taking into account the diagnostic species pool of the habitat.Since the management systems for coppices and HFs differ in cutting regime,we expect that they would cause different changes in floristic composition and richness.Methods The study area was the Montagne della Duchessa massif,in central italy.Structural differences and floristic richness were compared,and the diagnostic species diversity was analyzed using rarefaction curves and Rényi diversity profiles.Differences in understory com-position were analyzed through indicator species analysis.Important Findings Our results showed that,though the old coppices have a slightly higher number of understory species in general,the HF stands have greater mean species richness in both understory and diagnostic species,the latter being more evenly distributed inside the com-munity.These finding were related to the cut regime,which favor a constant canopy cover over time and thus the maintenance of more stable microclimatic conditions,promoting the higher abundance and evenness of shade-tolerant and vernal species.Conversely,the dense canopy of the old coppice appears to affect the understory richness by reducing the presence of light-demanding species,but still without a complete recolonization of the shade-tolerant spe-cies.Overall,our findings provide the first insights supporting that,in a Mediterranean montane context,old coppice conversion to HF could over time improve the species diversity in these habitats and help maintain good conservation status of the typical mature beech forests. 展开更多
关键词 diagnostic species habitat directive 92/43 EEC Mediterranean beech forests rarefaction curves Rényi diversity profiles SILVICULTURE understory diversity understory richness
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Structure changes and succession dynamic of the natural secondary forest after severe fire interference
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作者 LIU Bin-fan1,2, LIU Guang-ju2 , WANG Zhi-cheng3 1College of Forestry, Northeast Forestry University, Harbin 150040, P.R.China 2Heilongjiang Forest Engineering and Environment Research Institute, Harbin 150081, P.R.China 3Heilongjiang Forest Fire Prevention Office, Harbin 150090, P.R.China 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第A2期123-130,共8页
The structure and dynamic succession law of natural secondary forest after severe fire interference in recent 20 years were studied by adopting the method of deducing time series from the spatial sequence of vegetatio... The structure and dynamic succession law of natural secondary forest after severe fire interference in recent 20 years were studied by adopting the method of deducing time series from the spatial sequence of vegetation in Heihe region, Heilongjiang, China.Two typical and widely distributed forest types in the study area, namely forest type A and forest type B, were selected as study subjects.Forest type A is pure broadleaf forest or broadleaf mixed forest mainly composing of superior Betula platyphylla and Populus davidiana in the area with gradient <25°, while forest type B is pure forest or mixed forest composing of superior Quercus mongolica and Betula davurica in the area with gradient >25°.Species richness, vegetation coverage, important value, and similarity index of community in different layers(Herb, shrub, small tree, and arbor layers) were investigated and analyzed for the two typical forests.The results show that after fire interference, the species richness and coverage in each layer in forest type A were higher than that in forest type B.Both for forest type A and B, with elapse of post-fire years, the species richness and coverage of herbs and shrubs showed a decline tendency, while those of arbor layer present a rising tendency.Through comparison of the important values of species in each layer and analysis of community structure changes, the dynamic process of post-fire vegetation succession for forest type A and B was separately determined.Post-fire 80 years' succession tendency of forest type A is B.platyphylla and Larix gmelinii mixed forest.Its shrub layer is mainly composed of Corylus heterophylla and Vaccinium uliginosum, and herb layer is dominated by Carex tristachya, Athyrium multidentatum, and Pyrola incarnate;whereas, the post-fire 80 years' succession of forest type B is Q.mongolica and B.davurica mixed forest.Its shrub layer is mainly composed of lespedeza bicolar and corylus heterophylla and herb layer is dominated by Carex tristachya, Asparagus densiflorus, and Hemerocallis minor. 展开更多
关键词 natural secondary forest VEGETATION SUCCESSION FIRE INTERFERENCE burned areas species richness important value SIMILARITY index SUCCESSION law.
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Can picnic influence floral diversity and vitality of trees in Bhawal National Park of Bangladesh?
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作者 Md. Mizanur RAHMAN Harald VACIK 《Forestry Studies in China》 CAS 2009年第3期148-157,共10页
We examined the impact of picnic activities on forest diversity, structure, regeneration and vitality of tree species in the Bhawal National Park of Bangladesh. The study area was classified as a non-used, occasionall... We examined the impact of picnic activities on forest diversity, structure, regeneration and vitality of tree species in the Bhawal National Park of Bangladesh. The study area was classified as a non-used, occasionally used and frequently used area on the basis of the intensity of the picnic activities. A total of 43 plant species were enumerated in the whole study area. The highest plant species richness (41 species) was observed in the non-used area whereas the lowest species richness (11 species) in the frequently used area. The diversity index decreased with the increase of picnic intensity whereas the concentration of dominance increased. Density of all plant groups except mature trees, and the basal area of the mature trees showed a declining trend from the non-used to frequently used area. The frequently used area exhibited very poor regeneration. Tree vitality decreased with the increase of picnic intensity. The relevance of our study as a basis for further research to determine the impact of tourism on biodiversity in Bangladesh is discussed. 展开更多
关键词 species richness diversity index concentration of dominance REGENERATION INTENSITY
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Glade and Forest-Edge Plant Community Attributes for Three Glade Types in Arusha National Park, Tanzania
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作者 Ladislaus W. Kahana Gerard Malan Teresa J. Sylvina 《American Journal of Plant Sciences》 2022年第4期457-472,共16页
The aim of the study was to compare glade and forest-glade edge plant community attributes for man-made, upper and lower natural glades. Two plots were set up in twelve glades at 2.5, 12.5 m and three plots in thirtee... The aim of the study was to compare glade and forest-glade edge plant community attributes for man-made, upper and lower natural glades. Two plots were set up in twelve glades at 2.5, 12.5 m and three plots in thirteen glades at 2.5, 12.5 and 22.5 m depending on the size of the glade. The results showed that plants total abundance, percentage basal cover, species richness and species diversity for upper and lower natural glades differed significantly p < 0.05 and p < 0.01 respectively and species diversity for man-made glades p < 0.001. Plant species abundance, richness and diversity were highest at the forest-glade edge and decreased towards the glade interior. Plant species composition of the three glades types differed significantly (MRPP: T = -4.51, p < 0.001 and A = 0.17). Grasses’ total abundance and species richness and forbs species diversity differed significantly for man-made glades p < 0.01. For upper natural glades, grasses species richness was highly significant p < 0.001 while for forbs species richness and diversity were significant P < 0.01. Lower natural glades grasses and forbs’ total abundance, species richness and species diversity differed significantly p < 0.01 and p < 0.001 respectively. Growth forms in the lower natural glades were associated with the forest-glade edge or glade interior χ<sup>2</sup> = 15.95, df = 4, p Eleusine jaegeri, Heterogon contortus, Senna mimisoides, Digitaria scalarum, Clutia abyssinica) were habitat indicators for disturbed areas, wet humid grey/black clay soils for upper natural glades and three (Solanum incanum, Senna didymobotrya, and Pennistem mezianum, were indicators of overgrazed areas and black clay soils for man-made glades. In conclusion, plant species abundance, richness and diversity were highest at the forest-glade edge and decreased towards the glade interior, while plant species composition differed significantly between the three-glade types. The plant growth form for lower natural glades was associated with forest-glade edge and glade interior. 展开更多
关键词 forest Glade-Edge Glade Interior Plant Indicator species Plant species diversity Plant species richness
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