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Woody Diversity in Cult Places (Cemeteries, Mosques, and Parishes) in Ziguinchor City (Senegal)
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作者 Aly Diallo Antoine Sambou +4 位作者 Landing Ndiaye Jean Bassene Thierno Sarr Serigne Saliou Mbacke Ngom Elhadji Nfally Yoro Diedhiou 《American Journal of Plant Sciences》 2025年第1期114-132,共19页
Urban and peri-urban forests and trees play an important role by providing ecosystem services. Vegetation in sacred and cult places is among the useful forests and trees, but their characteristics are not well-documen... Urban and peri-urban forests and trees play an important role by providing ecosystem services. Vegetation in sacred and cult places is among the useful forests and trees, but their characteristics are not well-documented. It’s necessary to assess the potential of biodiversity conservation in sacred and cult places. This research aimed to enhance knowledge of the woody diversity in cult places in Ziguinchor. To achieve this, woody vegetation surveys were conducted to determine floristic composition and, diversity and structural parameters of woody vegetation. A total of 89 species belonging to 71 genera and 33 families were recorded, Fabaceae and Moraceae dominated in cemeteries and parishes, while Arecaceae and Euphorbiaceae were prevalent in mosques. Tree diversity varied according to cult places. Parishes recorded significatively higher diversity (2.2 ± 0.18) than cemeteries (1.59 ± 0.13) and mosques (1.07 ± 0.36). Cult places inflenced significatly the structural parameters. Tree density was higher in cemeteries (482.26 ± 302.71 indiv/ha) compared to parishes (197.61 ± 67.14 indiv/ha) and mosques (32.34 ± 4.89 indiv/ha). Mosques were characterized by higher canopy cover (25.43 ± 11.65 m2/ha), larger (83.72 ± 20.09 cm) and taller (16.28 ± 1.28 m) trees. Natural regeneration was also strongest in cemeteries (91.69% ± 3.715%), followed by parishes (62.22% ± 8.56%) and mosques (38.82% ± 14.5%). The cult places play an important ecological role in biodiversity conservation in urban and peri-urban areas. 展开更多
关键词 Tree diversity Biodiversity Conservation Cult Places
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Biodiversity metrics on ecological networks: Demonstrated with animal gastrointestinal microbiomes 被引量:1
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作者 Zhanshan(Sam)Ma Lianwei Li 《Zoological Research(Diversity and Conservation)》 2024年第1期51-65,共15页
Biodiversity has become a terminology familiar to virtually every citizen in modern societies.It is said that ecology studies the economy of nature,and economy studies the ecology of humans;then measuring biodiversity... Biodiversity has become a terminology familiar to virtually every citizen in modern societies.It is said that ecology studies the economy of nature,and economy studies the ecology of humans;then measuring biodiversity should be similar with measuring national wealth.Indeed,there have been many parallels between ecology and economics,actually beyond analogies.For example,arguably the second most widely used biodiversity metric,Simpson(1949)’s diversity index,is a function of familiar Gini-index in economics.One of the biggest challenges has been the high“diversity”of diversity indexes due to their excessive“speciation”-there are so many indexes,similar to each country’s sovereign currency-leaving confused diversity practitioners in dilemma.In 1973,Hill introduced the concept of“numbers equivalent”,which is based on Renyi entropy and originated in economics,but possibly due to his abstruse interpretation of the concept,his message was not widely received by ecologists until nearly four decades later.What Hill suggested was similar to link the US dollar to gold at the rate of$35 per ounce under the Bretton Woods system.The Hill numbers now are considered most appropriate biodiversity metrics system,unifying Shannon,Simpson and other diversity indexes.Here,we approach to another paradigmatic shift-measuring biodiversity on ecological networks-demonstrated with animal gastrointestinal microbiomes representing four major invertebrate classes and all six vertebrate classes.The network diversity can reveal the diversity of species interactions,which is a necessary step for understanding the spatial and temporal structures and dynamics of biodiversity across environmental gradients. 展开更多
关键词 Biodiversity on network Hill numbers Animal gut microbiome Network link diversity Network species diversity Network abundance-weighted link diversity
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Assessment of Floristic Diversity at Two Protected Sites on the Outskirts of Sena Oura National Park, Chad
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作者 Robert Tchingonta Maxime Banoin +1 位作者 Koussou Mian-Oudanang Sougnabe Pabame 《Agricultural Sciences》 2025年第1期178-192,共15页
Two protected sites located on the outskirts of the Sena Oura National Park (PNSO) in West Mayo-Kebbi cover an area of 1800 m2 is pattern choose in pastoral enclave in both village. This study was undertaken to highli... Two protected sites located on the outskirts of the Sena Oura National Park (PNSO) in West Mayo-Kebbi cover an area of 1800 m2 is pattern choose in pastoral enclave in both village. This study was undertaken to highlight the floristic diversity of the herbaceous and woody vegetation on these sites in the offing to know the ability of charge into UBT that most support the park peripheral. It took place on two experimental sites on a natural course in two villages: Wazetelan and Massang. The approach used for the study was a survey using the systematic sampling method and a 30 m × 30 m plot. The survey consisted in listing all the taxa in a floristically homogeneous plot, each assigned the Braun-Blanquet dominance abundance coefficient. These surveys revealed a floristic richness of 73 species, 58 genera, including 46 herbaceous and 26 woody species. The Shannon result gives H1' = 0.12 bit for herbaceous species and H2' = 0.44 bit for woody species, meaning that the herbaceous and woody populations of all the surveys have a very low species diversity, as H' < 3 according to the Shannon index assessment threshold. Herbaceous species are divided into 13 families and 33 genera. The most represented families are Fabaceae (27.3%) and Poaceae (21.9%). Most of the other families (1.3%) have only one species, if any. Herbaceous species are divided into 33 genera grouped into 13 families. The most represented families are Fabaces (16 species), 34%, and Poaceae (12 species), 26%. The 26 woody species, most of which come from itinerant surveys, are distributed across 24 genera and 12 families, the most important of which is Fabaceae with 09 species (34.6%). This floristic assessment, in terms of quantity and quality, has enabled us to estimate the carrying capacity of the two pastoral enclaves in Dari and Goumadji cantons, and to guide the government’s actions with regard to rangeland management. 展开更多
关键词 Floristic diversity Protected Sites PERIPHERY Area Producty CHAD
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Diversity and Morphometrics of Palm Weevils of the Genus Rhynchophorus in Maniema Province, Democratic Republic of Congo
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作者 Angundji Yumbi Chérif Muhigwa Bahananga Jean-Berckmans +2 位作者 Manga Tshomba Joseph Dieudonné Cikwanine Murhabale Cisirika Bertin 《Advances in Entomology》 2025年第1期152-173,共22页
An inventory of Rhynchophorus species was carried out to determine their diversity, biogeographical variability and morphometrics. A shotgun trapping method was used at nine sites in three districts over a four-month ... An inventory of Rhynchophorus species was carried out to determine their diversity, biogeographical variability and morphometrics. A shotgun trapping method was used at nine sites in three districts over a four-month period, identifying three species: R. quadrangulus, R. phoenicis, R. ferrugineus and a probable variant of R. phoenicis. Of these species, R. phoenicis stands out as the most widespread palm weevil, while the probable variant of R. phoenicis is considered the rarest subspecies in the Maniema region. The color of the head and elytra is a criterion for distinguishing the different species of Rhynchophorus spp. Morphological criteria indicate that the probable subspecies of R. phoenicis is the largest palm weevil in the Maniema region and even globally. It is followed by R. quadrangulus and, by far, by R. phoenicis. The smallest palm weevil in Maniema is R. ferrugineus. Moreover, these criteria reveal that, for all three species identified, the female is generally larger than the male. This study has the merit of extending the distribution of R. ferrugineus from the Maghreb to the central East of the DRC, and highlighting a subspecies of R. phoenicis. Recognition of the sexes on the basis of the shape of the tip of the abdomen (oval in the male and flat in the female) is an additional contribution. 展开更多
关键词 INVENTORY diversity MORPHOMETRICS Palm Weevils
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Associations between food insecurity with gestational diabetes mellitus and maternal outcomes mediated by dietary diversity:A cross-sectional study
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作者 Hong-Li Hou Gui-Xia Sun 《World Journal of Diabetes》 2025年第2期92-102,共11页
BACKGROUND Food insecurity(FI)during pregnancy negatively impacts maternal health and raises the risk of gestational diabetes mellitus(GDM)and pregnancy-induced hypertension(PIH),resulting in adverse outcomes for both... BACKGROUND Food insecurity(FI)during pregnancy negatively impacts maternal health and raises the risk of gestational diabetes mellitus(GDM)and pregnancy-induced hypertension(PIH),resulting in adverse outcomes for both mother and baby.AIM To investigate the relationships between FI and pregnancy outcomes,particularly GDM and PIH,while also examining the mediating role of the dietary diversity score(DDS).METHODS A cross-sectional study was undertaken to examine this relationship,involving 600 pregnant women.Participants were women aged 18 years or older who provided complete data on FI and pregnancy outcomes.The FI was measured via the Household Food Security Survey Module,with GDM defined as fasting plasma glucose levels of≥5.1 mmol/L or a 2-hour oral glucose tolerance test value of≥8.5 mmol/L.The DDS is determined by evaluating one's food consumption based on nine distinct food groups.A logistic regression model was used to explore the relationship between FI and PIH,and GDM.RESULTS Seventeen percent of participants reported experiencing FI during pregnancy.The study found a significant association between FI and an elevated risk of GDM[odds ratio(OR)=3.32,95%CI:1.2-5.4].Once more,food-insecure pregnant women had higher rates of PIH(OR=0.10,95%CI:0.02-0.45)and they also faced a higher likelihood of neonatal complications,such as neonatal intensive care unit’s admissions and the birth of infants with extremely low birth weight.The FI wasfurther linked to metabolic disruptions,such as elevated fasting blood sugar(FBS),low-density lipoprotein cholesterol,and triglyceride levels.Our results indicate that the DDS acts as a significant mediator in the relationship between FI and the incidence of GDM.In particular,the mediation analysis showed that approximately 65%of the effect was mediated through DDS(P=0.002).CONCLUSION These findings underscore the serious challenges that FI presents during pregnancy and its effects on maternal and infant health.Additionally,the study explored how DDS mediates the relationship between FI and the incidence of GDM. 展开更多
关键词 Food insecurity Gestational diabetes mellitus Gestational hypertension PREGNANCY Maternal health Infant health Dietary diversity score
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Assessing the effect of plot size on species diversity in a mixed oriental beech forest
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作者 Narges Kardgar Ramin Rahmani +1 位作者 Habib Zare Somayeh Ghorbani 《Journal of Forestry Research》 2025年第1期209-222,共14页
Plant species diversity is one of the most widely used indicators in ecosystem management.The relation of species diversity with the size of the sample plot has not been fully determined for Oriental beech forests(Fag... Plant species diversity is one of the most widely used indicators in ecosystem management.The relation of species diversity with the size of the sample plot has not been fully determined for Oriental beech forests(Fagus orientalis Lipsky),a widespread species in the Hyrcanian region.Assessing the impacts of plot size on species diversity is fundamental for an ecosystem-based approach to forest management.This study determined the relation of species diversity and plot size by investigating species richness and abundance of both canopy and forest floor.Two hundred and fifty-six sample plots of 625 m^(2) each were layout in a grid pattern across 16 ha.Base plots(25 m×25 m)were integrated in different scales to investigate the effect of plot size on species diversity.The total included nine plots of 0.063,0.125,0.188,0.250,0.375,0.500,0.563,0.750 and 1 ha.Ten biodiversity indices were calculated.The results show that species richness in the different plot sizes was less than the actual value.The estimated value of the Simpson species diversity index was not significantly different from actual values for both canopy and forest floor diversity.The coefficient of variation of this index for the 1-ha sample plot showed the lowest amount across different plot sizes.Inverse Hill species diversity was insignificant difference across different plot sizes with an area greater than 0.500 ha.The modified Hill evenness index for the 1-ha sample size was a correct estimation of the 16-ha for both canopy and forest floor;however,the precision estimation was higher for the canopy layer.All plots greater than 0.250-ha provided an accurate estimation of the Camargo evenness index for forest floor species,but was inaccurate across different plot sizes for the canopy layer.The results indicate that the same plot size did not have the same effect across species diversity measurements.Our results show that correct estimation of species diversity measurements is related to the selection of appropriate indicators and plot size to increase the accuracy of the estimate so that the cost and time of biodiversity management may be reduced. 展开更多
关键词 Species diversity Oriental beech forest Sample plot size Richness EVENNESS
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Construction of the porcine genome mobile element variations and investigation of its role in population diversity and gene expression
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作者 Jianchao Hu Lu Gui +1 位作者 Zhongzi Wu Lusheng Huang 《Journal of Animal Science and Biotechnology》 2025年第1期59-75,共17页
Background Mobile element variants(MEVs)have a significant and complex impact on genomic diversity and phe-notypic traits.However,the quantity,distribution,and relationship with gene expression and complex traits of M... Background Mobile element variants(MEVs)have a significant and complex impact on genomic diversity and phe-notypic traits.However,the quantity,distribution,and relationship with gene expression and complex traits of MEVs in the pig genome remain poorly understood.Results We constructed the most comprehensive porcine MEV library based on high-depth whole genome sequencing(WGS)data from 747 pigs across 59 breeds worldwide.This database identified a total of 147,993 poly-morphic MEVs,including 121,099 short interspersed nuclear elements(SINEs),26,053 long interspersed nuclear elements(LINEs),802 long terminal repeats(LTRs),and 39 other transposons,among which 54%are newly discovered.We found that MEVs are unevenly distributed across the genome and are strongly influenced by negative selec-tion effects.Importantly,we identified 514,530,and 584 candidate MEVs associated with population differentiation,domestication,and breed formation,respectively.For example,a significantly differentiated MEV is located in the ATRX intron between Asian and European pigs,whereas ATRX is also differentially expressed between Asian and European pigs in muscle tissue.In addition,we identified 4,169 expressed MEVs(eMEVs)significantly associated with gene expression and 6,914 splicing MEVs(sMEVs)associated with gene splicing based on RNA-seq data from 266 porcine liver tissues.These eMEVs and sMEVs explain 6.24%and 9.47%,respectively,of the observed cis-heritability and high-light the important role of MEVs in the regulation of gene expression.Finally,we provide a high-quality SNP–MEV reference haplotype panel to impute MEV genotypes from genome-wide SNPs.Notably,we identified a candidate MEV significantly associated with total teat number,demonstrating the functionality of this reference panel.Conclusions The present investigation demonstrated the importance of MEVs in pigs in terms of population diversity,gene expression and phenotypic traits,which may provide useful resources and theoretical support for pig genetics and breeding. 展开更多
关键词 Gene expression Genetic diversity Mobile element variants PIG SNP–MEV reference panel
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Genetic diversity and population genetic structure of Paeonia suffruticosa by chloroplast DNA simple sequence repeats(cpSSRs)
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作者 Qi Guo Xian Xue +5 位作者 Duoduo Wang Lixia Zhang Wei Liu Erqiang Wang Xiaoqiang Cui Xiaogai Hou 《Horticultural Plant Journal》 2025年第1期367-376,共10页
Paeonia suffruticosa Andr.is an endemic shrub flower in China with 2n=10.This study used 228 cultivars from four populations,i.e.,Jiangnan,Japan,Northwest,and Zhongyuan,as materials to explore the genetic diversity le... Paeonia suffruticosa Andr.is an endemic shrub flower in China with 2n=10.This study used 228 cultivars from four populations,i.e.,Jiangnan,Japan,Northwest,and Zhongyuan,as materials to explore the genetic diversity levels among different populations of tree peony varieties.The results showed that 34 bands were amplified using five pairs of cp SSR primers,with an average of 6.8 bands per primer pair.The average number of different alleles(N_(a)),effective alleles(N_(e)),Shannon's information index(I),diversity(H),and polymorphic information content(PIC)were 3.600,2.053,0.708,0.433,and 0.388,respectively.The PIC value was between 0.250 and 0.500,indicating a moderate level of polymorphism for the five cp SSR primer pairs.The genetic diversity levels of peony cultivars varied among different populations,with the Northwest population showing relatively lower levels(I=0.590,H=0.289,and PIC=0.263).A total of 52 haplotypes were identified in the four examined populations,and the number of haplotypes per population ranged from 11 to 22.Forty-four private haplotypes were detected across populations,and the Northwest population exhibiting the highest count of private haplotypes with 17.The mean number of effective number of haplotypes(N_(eh)),haplotypic richness(R_(h)),and diversity(H)were 8.351,6.824,and 0.893,respectively.Analysis of molecular variance indicated that genetic variation within tree peony germplasm was greater than that between germplasm resources,and the main variation was found within individuals of peony germplasm.Cluster analysis,principal coordinate analysis,and genetic structure analysis classified tree peonies from different origins into two groups,indicating a certain degree of genetic differentiation among these four tree peony cultivation groups.This study provides a theoretical basis for the exploration,utilization,and conservation of peony germplasm resources,as well as for research on the breeding of excellent varieties. 展开更多
关键词 Paeonia suffruticosa Chloroplast microsatellites(cp SSR) Genetic diversity Haplotypes Germplasm resources
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Effect of Collaborative Forest Management on Carbon Stocks, Species Diversity and Stem Density in Mabira Central Forest Reserve, Uganda*
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作者 Mugumya Phillipson Isabirye Moses Masaba Sowedi 《Open Journal of Forestry》 2025年第1期53-68,共16页
Collaborative forest management (CFM) is a form of forest governance in which local communities are involved in the management and decision-making processes related to forest resources. It is believed that forests und... Collaborative forest management (CFM) is a form of forest governance in which local communities are involved in the management and decision-making processes related to forest resources. It is believed that forests under such management are better in tree diversity and conservation status and thus hold more carbon stocks. The study assessed the impact of CFM on carbon stocks, tree species diversity & tree species density in Mabira Central Forest Reserve. Data were collected from plots that were systematically laid in the different purposively selected forest areas. The study findings show that there is no difference in stem density and carbon stocks between CFM and non-CFM areas. CFM areas had lower species richness compared to non-CFM areas. CFM areas, however, exhibited more species diversity than non-CFM areas. Climax colonization may favor a few dominant species over others, hence lowering species diversity despite the number of species being many in the understory, hence at the same time increasing species richness. Likewise, disturbance in CFM area may affect natural colonization and favor the emergency of many species either naturally or through assisted regeneration by reforestation, hence increasing diversity, whereas artificial selection of preferred species through harvesting may lower species richness, as observed. Recommendations for improving collaborative forest management (CFM) areas include implementing targeted interventions to enhance carbon sequestration, such as promoting reforestation and afforestation with high-carbon-storing species and strengthening monitoring and evaluation frameworks to assess carbon stock changes over time. Additionally, efforts should focus on enhancing biodiversity conservation by implementing more stringent protection measures and reducing human disturbance while encouraging community participation in biodiversity monitoring and conservation education. 展开更多
关键词 Collaborative Forest Management (CFM) Carbon Stocks Tree Species diversity Tree Stem-Densities Mabira Central Forest Reserve
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Board Diversity and Firm Performance: An Analysis Based on ROA and ROE of Singapore Exchange Listed Firms
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作者 Yilin Cheng Junshu Shen Huiping Zhang 《Proceedings of Business and Economic Studies》 2025年第1期127-138,共12页
This study explores the impact of board diversity on firm performance,with a focus on companies listed on the Singapore Stock Exchange(SGX).Board diversity is examined across various dimensions,including gender,age,et... This study explores the impact of board diversity on firm performance,with a focus on companies listed on the Singapore Stock Exchange(SGX).Board diversity is examined across various dimensions,including gender,age,ethnicity,and professional background,to understand its relationship with key performance indicators such as Return on Assets(ROA)and Return on Equity(ROE).Using a quantitative research approach,the study analyzes data from 90 publicly listed firms,employing descriptive statistics,correlation analysis,and multiple regression techniques.The findings reveal that the direct correlation between board diversity and financial performance,particularly in terms of ROA and ROE,is not statistically significant in the studied sample.Despite the lack of direct significance,the research underscores the nuanced and multifaceted role of diversity in corporate governance,suggesting that its impact may be more complex and influenced by various contextual factors.The study concludes by recommending that companies continue to enhance gender diversity,balance age structures,tailor professional backgrounds to industry needs,and manage board tenure effectively to optimize corporate governance and support sustainable growth. 展开更多
关键词 Board diversity Firm performance Singapore Stock Exchange(SGX) Return on Assets(ROA) Return on Equity(ROE) Corporate governance Sustainable growth
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Environment and management jointly shape the spatial patterns of plant species diversity of moist grasslands in the mountains of northeastern Yunnan
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作者 Jianghua Duan Liu Yang +5 位作者 Ting Tang Jiesheng Rao Wencong Liu Xi Chen Rong Li Zehao Shen 《Plant Diversity》 SCIE CAS CSCD 2024年第6期744-754,共11页
Grasslands account for about a quarter of the Earth's land area and are one of the major terrestrial ecosystems,with significant ecological and economic values.The influence of environmental factors and management... Grasslands account for about a quarter of the Earth's land area and are one of the major terrestrial ecosystems,with significant ecological and economic values.The influence of environmental factors and management types on grassland biodiversity has garnered considerable attention.This study investigated how patterns of species richness are influenced by geographical distance,environmental gradients,and management type in the moist mountain grasslands of northeastern Yunnan,China.We used structural equation modeling to disentangle the impacts of environment and management on phylogenetic community structure,and using partial Mantel tests estimated the roles of dispersal limitation and environmental filtering on taxonomic and phylogenetic beta diversity of three types of grasslands.Our results show that taxonomic alpha diversity increased in grazed grasslands and decreased in mowed grasslands,compared with protected grasslands.However,the phylogenetic structure of both grazed and mowed grassland communities was clustered,whereas that of protected communities was random.Moreover,both grazing and mowing significantly reduced the taxonomic and phylogenetic beta diversity of grasslands,with the lowest values observed in mowed grasslands.Both taxonomic and phylogenetic beta diversity were dominated by species turnover under different management types.The taxonomic and phylogenetic beta diversities of protected and grazed grasslands were simultaneously affected by environmental filtering and dispersal limitation,with the later playing a stronger role.In addition,mowing and following management measures had a stronger filtering effect on grassland community structure,as reflected by changes in community composition. 展开更多
关键词 Southern grasslands Alpha diversity Beta diversity Management type Environmental distance Spatial distance
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Strong evidence for latitudinal diversity gradient in mosses across the world
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作者 Hong Qian Zun Dai Jian Wang 《Plant Diversity》 SCIE CAS CSCD 2024年第4期537-541,共5页
Species richness generally decreases with increasing latitude,a biodiversity gradient that has long been considered as one of the few laws in ecology.This latitudinal diversity gradient has been observed in many major... Species richness generally decreases with increasing latitude,a biodiversity gradient that has long been considered as one of the few laws in ecology.This latitudinal diversity gradient has been observed in many major groups of organisms.In plants,the latitudinal diversity gradient has been observed in vascular plants,angiosperms,ferns,and liverworts.However,a conspicuous latitudinal diversity gradient in mosses at a global or continental scale has not been observed until now.Here,we analyze a comprehensive data set including moss species in each band of 20° in latitude worldwide.Our results show that moss species richness decreases strongly with increasing latitude,regardless of whether the globe is considered as a whole or different longitudinal segments(e.g.,Old World versus New World) are considered separately.This result holds when variation in area size among latitudinal bands is taken into account.Pearson's correlation coefficient between latitude and species richness is-0.99 for both the Northern and Southern Hemispheres.Because bryophytes are an extant lineage of early land plants and because mosses not only include most of extant species of bryophytes but also are important constituents of most terrestrial ecosystems,understanding geographic patterns of mosses is particularly important The finding of our study fills a critical knowledge gap. 展开更多
关键词 BRYOPHYTE Latitudinal diversity gradient MOSS Species density Species diversity
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No generality in biodiversity-productivity relationships along elevation in temperate and subtropical forest landscapes
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作者 Jiayun Zou Yahuang Luo +12 位作者 Rupert Seidl Dominik Thom Jie Liu Lisa Geres Tobias Richter Linjiang Ye Wei Zheng Liangliang Ma Jie Song Kun Xu Dezhu Li Lianming Gao Sebastian Seibold 《Forest Ecosystems》 SCIE CSCD 2024年第3期255-265,共11页
An improved understanding of biodiversity-productivity relationships(BPRs)along environmental gradients is crucial for effective ecosystem management and biodiversity conservation.The stress-gradient hypothesis sugges... An improved understanding of biodiversity-productivity relationships(BPRs)along environmental gradients is crucial for effective ecosystem management and biodiversity conservation.The stress-gradient hypothesis suggests that BPRs are stronger in stressful environments compared to more favorable conditions.However,there is limited knowledge regarding the variation of BPRs along elevational gradients and their generality across different landscapes.To study how BPRs change with elevation,we harnessed inventory data on 6,431 trees from152 plots surveyed twice in eight to ten year intervals in mountain forests of temperate Europe and subtropical Asia.We quantified the relationship between aboveground productivity and different biodiversity measures,including taxonomic,functional,and phylogenetic diversity.To elucidate the processes underlying BPRs,we studied the variation of different functional traits along elevation across landscapes.We found no general pattern of BPRs across landscapes and elevations.Relationships were neutral for all biodiversity measures in temperate forests,and negative for taxonomic and functional diversity in subtropical forests.BPRs were largely congruent between taxonomic,functional and phylogenetic diversity.We found only weak support for the stress-gradient hypothesis,with BPRs turning from negative to positive(effect not significant)close to the tree line in subtropical forests.In temperate forests,however,elevation patterns were strongly modulated by species identity effects as influenced by specific traits.The effect of traits such as community-weighted mean of maximum plant height and wood density on productivity was congruent across landscapes.Our study highlights the context-dependence of BPRs across elevation gradients and landscapes.Species traits are key modulating factors of BPRs and should be considered more explicitly in studies of the functional role of biodiversity.Furthermore,our findings highlight that potential trade-offs between conserving biodiversity and fostering ecosystem productivity exist,which require more attention in policy and management. 展开更多
关键词 Biodiversity-ecosystem functioning Climate mitigation Elevation gradients Forest management Forest productivity Functional traits Nature conservation Phylogenetic diversity
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Island biogeography theory and the habitat heterogeneity jointly explain global patterns of Rhododendron diversity
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作者 Yanwei Guan Yongru Wu +4 位作者 Zheng Cao Zhifeng Wu Fangyuan Yu Haibin Yu Tiejun Wang 《Plant Diversity》 SCIE CAS CSCD 2024年第5期565-574,共10页
Mountain biodiversity is of great importance to biogeography and ecology.However,it is unclear what ecological and evolutionary processes best explain the generation and maintenance of its high levels of species diver... Mountain biodiversity is of great importance to biogeography and ecology.However,it is unclear what ecological and evolutionary processes best explain the generation and maintenance of its high levels of species diversity.In this study,we determined which of six common hypotheses(e.g.,climate hypotheses,habitat heterogeneity hypothesis and island biogeography theory)best explain global patterns of species diversity in Rhododendron.We found that Rhododendron diversity patterns were most strongly explained by proxies of island biogeography theory(i.e.,mountain area)and habitat heterogeneity(i.e.,elevation range).When we examined other relationships important to island biogeography theory,we found that the planimetric area and the volume of mountains were positively correlated with the Rhododendron diversity,whereas the‘mountains-to-mainland’distance was negatively correlated with Rhododendron diversity and shared species.Our findings demonstrate that Rhododendron diversity can be explained by island biogeography theory and habitat heterogeneity,and mountains can be regarded as islands which supported island biogeography theory. 展开更多
关键词 Mountain biodiversity RHODODENDRON Island biogeography theory Habitat heterogeneity Biogeographical hypotheses Plant diversity
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Diversity-biomass relationships are shaped by tree mycorrhizal associations and stand structural diversity at different spatial scales
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作者 Rui Zhang Shuaifeng Li +3 位作者 Xiaobo Huang Cong Li Chonghua Xu Jianrong Su 《Forest Ecosystems》 CSCD 2024年第6期781-792,共12页
Diversity-biomass relationships(DBRs)in terrestrial ecosystems tend to vary across spatial scales,but,particularly in hyperdiverse forests,the mechanisms driving these trends remain uncertain.Until now,few have simult... Diversity-biomass relationships(DBRs)in terrestrial ecosystems tend to vary across spatial scales,but,particularly in hyperdiverse forests,the mechanisms driving these trends remain uncertain.Until now,few have simultaneously investigated the connections between tree species diversity,stand structural diversity,mycorrhizal associations,and ecosystem functioning.In addition,DBRs have only been studied at limited spatial scales,with limited focus on the direct and indirect effects of environmental factors.We addressed these research gaps using a 30-ha forest dynamics plot located in Pu'er City,Southwest China.Through piecewise structural equation models,we quantified the direct effects of tree species diversity(α,β,γ),stand structural diversity,mycorrhizal associations(AM,EcM),and the environmental factors(soil fertility and topography),as well as the indirect effects of the environmental factors on aboveground tree biomass across spatial scales ranging from 400 to 230,400 m^(2).We hypothesized that complex interactions among these factors underpin the variation in DBRs in natural ecosystems across spatial scales.Our results showed that environmental conditions indirectly affected the tree biomass via changes in tree species diversity,and these effects became stronger as the spatial scale increased.At small to moderate spatial scales,environmental factors were more predictive of tree biomass than tree species diversity(or its components);the effects of stand structural diversity on biomass also gradually increased with spatial scale.Conversely,from the intermediate to the largest spatial scales,mycorrhizal associations gradually became the best predictors of DBR dynamics.Our research offers novel empirical evidence demonstrating the importance of environmental conditions,structural diversity,and mycorrhizal associations in shaping cross-scale DBRs.Future comprehensive studies should consider these factors to assess the mechanisms shaping scale-dependent DBRs in complex natural ecosystems. 展开更多
关键词 Spatial scales Mycorrhizal dominance Aboveground biomass Environmental factors Stand structural diversity Biodiversity-ecosystem functioning Monsoon evergreen broad-leaved forest
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Biodiversity Assessment of Avifauna in the Forest Reservation of Aurora State College of Technology (ASCOT), Philippines
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作者 Afed S. Daiwey Heherson B. Ong +3 位作者 Emerson V. Barcellano Edmundo C. Gumpal Michelle Ann M. Calubaquib Rafael J. Padre 《Open Journal of Ecology》 2024年第4期292-308,共17页
The research study was conducted to assess and quantify the current status of avifauna biodiversity assets of Aurora State College of Technology’s Forest Reservation in Baler, Aurora, Philippines. Assessment of avifa... The research study was conducted to assess and quantify the current status of avifauna biodiversity assets of Aurora State College of Technology’s Forest Reservation in Baler, Aurora, Philippines. Assessment of avifaunal diversity was undertaken by traversing the four established circular plots having a radius of 125 meters or 250 meters diameters each as permanent monitoring stations. Study revealed a total number of 151 Individual species, classified into 23 genera and 21 families. Eighteen of these species are endemic while the remaining five were fully migrated birds. All birds observed were classified as Least Concern (LC) species according to the International Union for Conservation of Nature’s Red List of Threatened Species and the updated list of the Birds of the World online. Its abundance, richness and diversity index were calculated using Shannon Diversity Index (H') while Pielou’s evenness (J') for distribution of species. Forest reservation of ASCOT has more even (0.756 J') and moderate diversity (2.812 H') observation on avifauna in general. However, this avian population evaluation was threatened into a verge of extinction due to natural and anthropological threats that causes forest deforestation. Such deforestation of habitat causes dwindling of wildlife territory leading to the scarcity of bird’s population. Thus, the assessment was conducted to aid ASCOT administration find significant plans to ensure sustainable conservation and protection of the remaining avifauna species in the reservation area. 展开更多
关键词 BIOdiversity AVIFAUNA ABUNDANCE Species Richness Species diversity
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Evaluating the Impacts of Human Activities on Diversity, Abundance, and Distribution of Large Mammals in Nimule National Park, South Sudan
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作者 Abdallah Gordon Shazali Joseph Mayindo Mayele +1 位作者 Joel Emmanuel Saburi Jubara Nadlin 《Open Journal of Ecology》 2024年第5期483-507,共25页
Globally, human activities have a significant impact on the diversity, abundance, and distribution of large mammals in Protected Areas (PAs). These disturbances increase human pressure on biodiversity and species habi... Globally, human activities have a significant impact on the diversity, abundance, and distribution of large mammals in Protected Areas (PAs). These disturbances increase human pressure on biodiversity and species habitats, highlighting the need for conservation. This study aimed to assess the abundance and distribution of large mammals in different habitat types within Nimule National Park (NNP) and understand the impacts of human activities on them. Data on the abundance and distribution of large mammals and their respective habitat types were collected through line transect surveys. Human activity signs were observed and recorded along the transect lines. To estimate the impacts of human activities on the diversity, abundance, and distribution of large mammal species, as well as to identify any significant differences between them and their habitat types, the study utilized the Kruskal Wallis test, Polynomial multiple regressions, and diversity indices. The findings from the Shannon-Weiner and Simpson indices indicated that large mammal species were more diverse inside the park (H’ = 1.136;D = 0.570) compared to the buffer zone (H’ = 0.413;D = 0.171), with 85% (443 out of 510 samples) recorded within Nimule National Park. The species abundance showed a semi-balanced status (0.58). The diversity results among different habitat types revealed that large mammals were more diverse and highly distributed in both open woodlands (244) and dense woodlands (192), while riverine vegetation had the lowest diversity (8). Statistical tests demonstrated a highly significant difference at a 99% confidence interval (p-value = 0.01) between habitat types and identified species of large mammals. Additionally, the results highlighted the high abundance of Uganda kob (274), baboons (141), and warthog (57) across most habitat types, accounting for at least 75% of their distribution. The most prevalent human activities observed were cattle footprints (27%) and cattle dung (14%). Human footprints and tree cutting combined accounted for 9%, indicating the practice of livestock grazing, poaching, encroachment, and fuelwood collection by local communities. However, these activities did not appear to significantly impact the diversity, abundance, and distribution of large mammals in Nimule National Park. Therefore, it is crucial to foster shared responsibilities and engage relevant stakeholders in the management and conservation of large wildlife species. Regular community awareness programs should be implemented to cultivate a sense of ownership. Moreover, it is recommended that a comprehensive survey be conducted on the population status of all mammal species in Nimule National Park, including its surrounding Buffer Zone. Monitoring the impact of human activities on their behavior and habitats using satellite images should also be carried out at least every five to ten years. 展开更多
关键词 diversity of Large Mammals Abundance and Distribution IMPACTS Biodiversity Conservation Human Activities Nimule National Park South Sudan
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Mapping and Floristic Diversity of the Nakpadjouak Community Forest, Tami Canton, Togo (West Africa)
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作者 Senyo Kossi Ehlui Christian Anthony-Krueger +4 位作者 Edinam Kola Wouyo Atakpama Alagie Bah Henrik von Wehrden Tchaa Boukpessi 《Natural Resources》 2024年第4期83-105,共23页
Since 2015, community forests have been promoted in Togo as an alternative to protect areas from degradation and as a means of contributing to forest landscape restoration. The study focuses on the Nakpadjouak Communi... Since 2015, community forests have been promoted in Togo as an alternative to protect areas from degradation and as a means of contributing to forest landscape restoration. The study focuses on the Nakpadjouak Community Forest (NCF) in Tami (Togo, West Africa) which contributes to community forests sustainable management. It aims in (i) mapping forest ecosystems and analysing their dynamic and (ii) characterizing the floristic diversity of the NCF. The ecosystems were mapped and their dynamic was evaluated based on Google Earth images of 2014 and 2020. Floristic and forestry inventories were carried out using the transect technique in a sample of 20 plots of 50 m × 20 m. The NCF was made up mainly by wooded/shrub savannahs (95.37%) and croplands/fallow (4.63%) in 2014. These two land use types undergone changes over the 6 years prior to 2020. By 2020, the NCF had 3 land use types: wooded/shrub savannahs (77.59%), open forest/wooded savannahs (22.23%), and croplands/fallows (0.18%). A total of 89 plant species belonging to 70 genera and 28 families were recorded within the NCF. The dominant species are: Heteropogon contortus (L.) P.Beauv. and Combretum collinum Fresen. followed by Pteleopsissuberosa Engl. & Diels, Annona senegalensis Pers. The most common species are: Lannea acida A.Rich. s.l., A. senegalensis, Vitellaria paradoxa C.F.Gaertner subsp. paradoxa, C. collinum and Acacia dudgeonii Craib ex Holland. Due to its small area of just 40 hectares and its diverse plant life, this community forest of Savannahs Region is a significant biodiversity hotspot and warrants conservation efforts. 展开更多
关键词 Community Forest Floristic diversity Land Use Change Biodiversity Hotspot Tami Savannah Region TOGO
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The Super-population Bridges the Habitat Diversity and Biodiversity 被引量:3
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作者 李天星 《Agricultural Science & Technology》 CAS 2009年第6期11-14,19,共5页
There is another way for new species to invade former settlers' habitats and successfully settle there; it is demonstrated that the su- per-population, which plays a key role in changing the world-wide environment, c... There is another way for new species to invade former settlers' habitats and successfully settle there; it is demonstrated that the su- per-population, which plays a key role in changing the world-wide environment, can create many new microhabitats in the old habitat, it is these new microhabitats that make new species easily come into the old habitat and settle there without fierce competition with former settlers. In other words, the super-population lead to the differentiation of the worldwide environment, lead to the environmental diversity in the biosphere. Through the differentiation of the environment the super-population produces many new microhabitats for new species, the appearance of many new microhabitats make it possible for new species to coexist with former settlers in the biosphere. The cqexistence of new species with former settlers or with new species' "ancestors" results in the increaseing in the biodiversity of the biosphere. The super-population is the founder of many new environments on the earth, it bridges the habitat diversity and the biodiversity. Now It is easy to explain the phenomenon that new species sometimes coexist with former settlers and even depend on former settlers in the biosphere rather than fierce competition between them. 展开更多
关键词 Super-population MICROHABITAT Habitat diversity Species diversity BIOdiversity
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Community structure and species diversity dynamics of a subtropical evergreen broad-leaved forest in China:2005 to 2020 被引量:2
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作者 Shi-Guang Wei Lin Li +3 位作者 Kun-Dong Bai Zhi-Feng Wen Jing-Gang Zhou Qin Lin 《Plant Diversity》 SCIE CAS CSCD 2024年第1期70-77,共8页
Here,we characterize the temporal and spatial dynamics of forest community structure and species diversity in a subtropical evergreen broad-leaved forest in China.We found that community structure in this forest chang... Here,we characterize the temporal and spatial dynamics of forest community structure and species diversity in a subtropical evergreen broad-leaved forest in China.We found that community structure in this forest changed over a 15-year period.Specifically,renewal and death of common species was large,with the renewal of individuals mainly concentrated within a few populations,especially those of Aidia canthioides and Cryptocarya concinna.The numbers of individual deaths for common species were concentrated in the small and mid-diameter level.The spatial distribution of community species diversity fluctuated in each monitoring period,showing a more dispersed diversity after the 15-year study period,and the coefficient of variation on quadrats increased.In 2010,the death and renewal of the community and the spatial variation of species diversity were different compared to other survey years.Extreme weather may have affected species regeneration and community stability in our subtropical monsoon evergreen broad-leaved forests.Our findings suggest that strengthening the monitoring and management of the forest community will help better understand the long-and short-term causes of dynamic fluctuations of community structure and species diversity,and reveal the factors that drive changes in community structure. 展开更多
关键词 Community structure Death and renewal dynamics Species diversity dynamics South subtropical forest
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