Objective Evidence suggests that depleted gut microbialα-diversity is associated with hypertension;however,whether metabolic markers affect this relationship remains unknown.We aimed to determine the potential metabo...Objective Evidence suggests that depleted gut microbialα-diversity is associated with hypertension;however,whether metabolic markers affect this relationship remains unknown.We aimed to determine the potential metabolites mediating the associations ofα-diversity with blood pressure(BP)and BP variability(BPV).Methods Metagenomics and plasma targeted metabolomics were conducted on 523 Chinese participants from the MetaSalt study.The 24-hour,daytime,and nighttime BP and BPV were calculated based on ambulatory BP measurements.Linear mixed models were used to characterize the relationships betweenα-diversity(Shannon and Chao1 index)and BP indices.Mediation analyses were performed to assess the contribution of metabolites to the observed associations.The influence of key metabolites on hypertension was further evaluated in a prospective cohort of 2,169 participants.Results Gut microbial richness(Chao1)was negatively associated with 24-hour systolic BP,daytime systolic BP,daytime diastolic BP,24-hour systolic BPV,and nighttime systolic BPV(P<0.05).Moreover,26 metabolites were strongly associated with richness(Bonferroni P<0.05).Among them,four key metabolites(imidazole propionate,2-hydroxy-3-methylbutyric acid,homovanillic acid,and hydrocinnamic acid)mediated the associations between richness and BP indices(proportions of mediating effects:14.1%–67.4%).These key metabolites were also associated with hypertension in the prospective cohort.For example,each 1-standard deviation unit increase in hydrocinnamic acid significantly reduced the risk of prevalent(OR[95%CI]=0.90[0.82,0.99];P=0.03)and incident hypertension(HR[95%CI]=0.83[0.71,0.96];P=0.01).Conclusion Our results suggest that gut microbial richness correlates with lower BP and BPV,and that certain metabolites mediate these associations.These findings provide novel insights into the pathogenesis and prevention of hypertension.展开更多
The latitudinal diversity gradient(LDG)is one of the most notable biodiversity patterns in biogeography.The metabolic theory of ecology(MTE)explains ecological patterns,including the LDG.However,little is known about ...The latitudinal diversity gradient(LDG)is one of the most notable biodiversity patterns in biogeography.The metabolic theory of ecology(MTE)explains ecological patterns,including the LDG.However,little is known about whether the LDG remains stable over time as climate warming progresses and whether MTE remains applicable to clarify this pattern.In this study,forest data spanning temperate,subtropical,and tropical zones across China were used to analyze long-term changes in the LDG of tree species over 2005-2020.Based on the MTE framework,spatial scales were considered to assess temperature dependence of typical forest trees species.Our results show that species richness decreased with increasing latitude,and that temperature was the primary driver of this change.Although temperature in China has significantly increased over the past two decades,the LDG of tree species has remained stable.However,there was a decrease in species richness in tropical regions over time.With predictions of the MTE,the logarithm of typical forest tree species richness exhibited negative linear relationships with the inverse of ambient temperature,indicating temperature dependence of species richness.However,the relationship remained stable and was strongly influenced by spatial scale,intensifying as spatial scale increased.The findings emphasize the important role of temperature in shaping the LDG.The effects of spatial scale,in particular,should be considered when biodiversity management plans are developed for future climate change.展开更多
Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmen...Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmental gradients.Particularly,the relative importance(RIV)of different plant life forms in a community and how they vary with environmental variables are still unclear.To fill these gaps,we determined plant diversity of ephemeral plants,annual herbs,perennial herbs,and woody plants from 187 sites across drylands in China.The SR patterns of herbaceous plants,especially perennial herbs,and their RIV in plant communities increased with increasing precipitation and soil nutrient content;however,the RIV of annual herbs was not altered along these gradients.The SR and RIV of ephemeral plants were affected mainly by precipitation seasonality.The SR of woody plants had a unimodal relationship with air temperature and exhibited the highest RIV and SR percentage in plant communities under the harshest environments.An obvious shift emerged in plant community composition,SR and their critical impact factors at 238.5 mm of mean annual precipitation(MAP).In mesic regions(>238.5 mm),herbs were the dominant species,and the SR displayed a relatively slow decreasing rate with increasing aridity,which was mediated mainly by MAP and soil nutrients.In arid regions(<238.5 mm),woody plants were the dominant species,and the SR displayed a relatively fast decreasing rate with increasing aridity,which was mediated mainly by climate variables,especially precipitation.Our findings highlight the importance of comparative life form studies in community structure and biodiversity,as their responses to gradients differed substantially on a large scale.展开更多
The entomofauna in the Republic of Congo is very little known. Studies carried out in natural forests are few. It is in this context that this inventory of entomofauna was carried out from April to July 2022 in the Sc...The entomofauna in the Republic of Congo is very little known. Studies carried out in natural forests are few. It is in this context that this inventory of entomofauna was carried out from April to July 2022 in the Scientific City Forest. The general objective is to contribute to the knowledge of the trapping, mowing and sight hunting;the three types of traps used are: Barber pots, colored plates and aerial traps. This study made it possible to invent 1523 specimens belonging to 106 species, 99 genera, 59 families and 12 orders. The order Diptera is the most abundant and richest in species (47% and 26%). This order is followed by Hymenoptera (23% and 23%). Formicidae (14%) and Calliphoridae (13%) are the most abundant families. The Formicidae family presents the greatest species richness (7%), Calliphora sp and Polyrhachis cyaniventris present the highest specific relative abundance of the entire collection. These preliminary results of the entomofauna of Scientific City constitute a database. However, this study must be continued and extended to other areas of Brazzaville, using other capture techniques and taking into account the seasons.展开更多
Insects represent an important taxon for the functioning of ecosystems. They also contribute to human and animal nutrition and are vector agents of several diseases. In Congo-Brazzaville the diversity of entomofauna i...Insects represent an important taxon for the functioning of ecosystems. They also contribute to human and animal nutrition and are vector agents of several diseases. In Congo-Brazzaville the diversity of entomofauna is very little known. The present study aimed to investigate ponds. The inventory of insects was conducted in ponds Ngatsouéné and Yo, the first one was located in the center of Djambala and the last one was 2 km from the center of the city. The insects were caught with an entomological net from 23rd to 24th December 2012. The study identifies 37 species belonging to 17 families and 7 orders. This entomofauna study showed a high proportion of the Orthoptera order (27.20%). Family Mantidae has the largest species number (13.51%). Mantis sp is the most abundant species (13.51%). This is a database and therefore, should be extended to different aquatic ecosystems of the Department of Plateaux. The results obtained during this study will contribute to the development of a database for the management of entomofauna in Congo.展开更多
The primary mechanism driving plant species loss after nitrogen(N)addition has been often hypothesized to be asymmetric competition for light,resulting from increased aboveground biomass.However,it is largely unknown ...The primary mechanism driving plant species loss after nitrogen(N)addition has been often hypothesized to be asymmetric competition for light,resulting from increased aboveground biomass.However,it is largely unknown whether plants’access to soil water at different depths would affect their responses,fate,and community composition under nitrogen addition.In a semiarid grassland exposed to 8-years of N addition,we measured plant aboveground biomass and diversity under four nitrogen addition rates(0,4,10,and 16 g m2 year1),and evaluated plant use of water across the soil profile using oxygen isotope.Aboveground biomass increased significantly,but diversity and shallow soil-water content decreased,with increasing rate of nitrogen addition.The water isotopic signature for both plant and soil water at the high N rate indicated that Leymus secalinus(a perennial grass)absorbed 7%more water from the subsurface soil layer(20e100 cm)compared to Elymus dahuricus(a perennial grass)and Artemisia annua(an annual forb).L.secalinus thus had a significantly larger biomass and was more abundant than the other two species at the high N rate but did not differ significantly from the other two species under ambient and the low N rate.Species that could use water from deeper soil layers became dominant when water in the shallow layers was insufficient to meet the demands of increased aboveground plant biomass.Our study highlights the importance of water across soil depths as key driver of plant growth and dominance in grasslands under N addition.展开更多
Species richness in any area results from the interplay of the processes of speciation,extinction,and dispersal.The relationships between species richness and climate should be considered as an outcome of the effects ...Species richness in any area results from the interplay of the processes of speciation,extinction,and dispersal.The relationships between species richness and climate should be considered as an outcome of the effects of climate on speciation,extinction,and dispersal.Diversificationrate represents the balance of speciation and extinction rates over time.Here,I explore diversificationrates in mosses across geographic and climatic gradients worldwide.Specifically,I investigate latitudinal patterns and climatic associations of the mean diversificationrate of mosses at global,hemispheric,and smaller scales.I findthat the mean diversificationrate of mosses is positively correlated with species richness of mosses,increases with decreasing latitude and increasing mean annual temperature and annual precipitation,and is more strongly associated with mean annual temperature than with annual precipitation.These findingsshed light on variation of species richness in mosses across the world.The negative relationship between species richness and latitude and the positive relationship between species richness and mean diversificationrate in mosses suggest that higher moss species richness at lower latitudes might have resulted,at least to some degree,from higher moss diversificationrates at lower latitudes.展开更多
Microplastics (MPs), fluoride (FR), and fungicide mancozeb (MZ) are common contaminants in soil. However, there is no information about the combined impacts of MPs, FR, and MZ on tomato plant growth features in the li...Microplastics (MPs), fluoride (FR), and fungicide mancozeb (MZ) are common contaminants in soil. However, there is no information about the combined impacts of MPs, FR, and MZ on tomato plant growth features in the literature. This study aimed to investigate the effects of combined application of MPs, FR, and MZ (both analytical grade and commercial) on the growth and development of tomato plants and metagenomics of rhizosphere soil. A pot experiment was set up in an artificial greenhouse with two sets of treatments. One set was the combined application of MPs, FR, and analytical grade MZ (B2) and a control without the application of MPs, FR, and MZ (W2), and the other set was the combined application of MPs, FR, and commercial MZ (B3) and a control without the application of MPs, FR, and MZ (W3). No detrimental effects of MPs, FR, and MZ were detected on the growth parameters of tomato plants, including the number of leaves and chlorophyll concentration. However, tomato roots showed knot and nodulation-type structures, and metabolomic profiling revealed that combined exposure to MPs, FR, and MZ profoundly reprogrammed the primary metabolism in tomato roots, with marked alterations in carbohydrate and amino acid pathways. Metagenome whole genome sequencing showed that the B2 and B3 treatments profoundly affected soil microbial community composition, diversity, gene abundances, and functional gene variations compared to W2 and W3. Proteobacteria became the dominating phylum in B2 and B3, causing a significant shift in the microbiome. Its abundance soared to 66.7% in B2 and 75.4% in B3, compared to only 35.9% in W2 and 28.9% in W3. On the other hand, Actinobacteria decreased significantly from 55.6% in W2 and 63.8% in W3 to 18.1% in B2 and 9.6% in B3. This study highlights the microbial shifts due to combined application of MPs, FR, and MZ, providing evidence for understanding their environmental risks.展开更多
Functional traits are characteristics associated with the growth,reproduction,and survival of individuals.Studying them helps us understand how species traits drive ecosystem functioning.Thus,we evaluated the differen...Functional traits are characteristics associated with the growth,reproduction,and survival of individuals.Studying them helps us understand how species traits drive ecosystem functioning.Thus,we evaluated the differences in traits and functional diversity between forest edges and interiors,and how the inclusion of intraspecific trait variation affects the assessment of functional diversity in these habitats.We sampled 10 representative forest patches,and,in each patch,we established five plots on the edge and five inside the forest,collecting leaf functional traits,allometric and wood density for all species.We assessed functional diversity using functional richness(FRic),divergence(FDiv),and dispersion(FDis).To assess the impact of incorporating intraspecific variation when comparing trait values and functional diversity indices,we established two scenarios:one that excludes intraspecific variation and another that includes it.We found that the edge and interior harbor individuals with distinct functional traits that alleviate the inherent stress of each habitat.The edge was also found to be more selective in terms of the range of functional traits,resulting in lower functional diversity.Our findings demonstrated that habitats play an important role in intraspecific trait variation(ITV)and that statistically significant differences between habitats,in relation to traits and functional diversity,were better observed with the inclusion of intraspecific variation.Our study highlights the potential of using natural forest patches to understand the edge effect,regardless of habitat loss.Additionally,we emphasize the importance of incorporating ITV into functional diversity studies,especially those on a smaller scale that incorporate quantitative variables,to better understand and predict ecological patterns.展开更多
Magnesium-lithium hybrid batteries(MLHBs)have gained increasing attention due to their combined advantages of rapid ion insertion/extraction cathode and magnesium metal anode.Herein,Sn S_(2)-SPAN hybrid cathode with s...Magnesium-lithium hybrid batteries(MLHBs)have gained increasing attention due to their combined advantages of rapid ion insertion/extraction cathode and magnesium metal anode.Herein,Sn S_(2)-SPAN hybrid cathode with strong C-Sn bond and rich defects is ingeniously constructed to realize Mg^(2+)/Li^(+)co-intercalation.The physical and chemical double-confinement synergistic engineering of sulfurized polyacrylonitrile can suppress the agglomeration of Sn S_(2)nanoparticles and the volume expansion,simultaneously promote charge transfer and enhance structural stability.The introduced abundant sulfur vacancies provide more active sites for Mg^(2+)/Li^(+)co-intercalation.Meanwhile,the beneficial effects of rich sulfur defects and C-Sn bond on enhanced electrochemical properties are further evidenced by density-functional theory(DFT)calculations.Therefore,compared with pristine SnS_(2),SnS_(2)-SPAN cathode displays high specific capacity(218 m Ah g^(-1)at 0.5A g^(-1)over 700 cycles)and ultra-long cycling life(101 m Ah g^(-1)at 5 A g^(-1)up to 28,000 cycles).And a high energy density of 307 Wh kg^(-1)can be realized by the Sn S_(2)-SPAN//Mg pouch cell.Such elaborate and simple design supplies a reference for the exploitation of advanced cathode materials with excellent electrochemical properties for MLHBs.展开更多
In floristic research,the grid mapping method is a crucial and highly effective tool for investigating the flora of specific regions.This methodology aids in the collection of comprehensive data,thereby promoting a th...In floristic research,the grid mapping method is a crucial and highly effective tool for investigating the flora of specific regions.This methodology aids in the collection of comprehensive data,thereby promoting a thorough understanding of regional plant diversity.This paper presents findings from a grid mapping study conducted in the Surkhan-Sherabad botanical-geographic region(SShBGR),acknowledged as one of the major floristic areas in southwestern Uzbekistan.Using an expansive dataset of 14,317 records comprised of herbarium specimens and field diary entries collected from 1897 to 2023,we evaluated the stages and seasonal dynamics of data accumulation,species richness(SR),and collection density(CD)within 5 km×5 km grid cells.We further examined the taxonomic and life form composition of the region's flora.Our analysis revealed that the grid mapping phase(2021–2023)produced a significantly greater volume of specimens and taxonomic diversity compared with other periods(1897–1940,1941–1993,and 1994–2020).Field research spanned 206 grid cells during 2021–2023,resulting in 11,883 samples,including 6469 herbarium specimens and 5414 field records.Overall,fieldwork covered 251 of the 253 grid cells within the SShBGR.Notably,the highest species diversity was documented in the B198 grid cell,recording 160 species.In terms of collection density,the E198 grid cell produced 475 samples.Overall,we identified 1053 species distributed across 439 genera and 78 families in the SShBGR.The flora of this region aligned significantly with the dominant families commonly found in the Holarctic,highlighting vital ecological connections.Among our findings,the Asteraceae family was the most polymorphic,with 147 species,followed by the continually stable and diverse Poaceae,Fabaceae,Brassicaceae,and Amaranthaceae.Besides,our analysis revealed a predominance of therophyte life forms,which constituted 52%(552 species)of the total flora.The findings underscore the necessity for continual data collection efforts to further enhance our understanding of the biodiversity in the SShBGR.The results of this study demonstrated that the application of grid-based mapping in floristic studies proves to be an effective tool for assessing biodiversity and identifying key taxonomic groups.展开更多
Anthropogenic activities have significantly contributed to the loss and fragmentation of primary forests across the globe,which has accelerated biodiversity decline,particularly among highly specialised species depend...Anthropogenic activities have significantly contributed to the loss and fragmentation of primary forests across the globe,which has accelerated biodiversity decline,particularly among highly specialised species dependent on unique forest structures.Nevertheless,comparative studies between primary and managed forests are scarce,despite their importance for effective monitoring and conservation planning.To address this knowledge gap,we conducted a comparative study using a unique dataset of permanent study plots established across some of the best-preserved,mixed-beech primary forests and their adjacent managed counterparts in the Western Carpathian Mountains.We assessed the effects of forest structure and tree age—determined through extensive dendrochronological reconstructions—on contemporary lichen communities.Lichen species richness and the richness of red-listed species were 26%and 50%higher in primary forests than in managed forests,respectively,highlighting the outstanding conservation importance of primary forests.Generalised least squares(GLS)modelling demonstrated that in managed forests,lichen species richness was strongly associated with structural attributes:It increased with maximum tree age and the diameter of standing deadwood,and decreased with higher basal area(BA)of living trees,likely due to reduced understory light.In contrast,no structural variables significantly explained richness in primary forests,likely due to structural saturation and widespread microhabitat availability.Elevation emerged as the sole variable with significant explanatory strength.These findings underscore the critical role of structural complexity in supporting lichen diversity under different management regimes and provide a robust evidence base for promoting elements such as old trees,deadwood—especially large standing deadwood—and reduced canopy density.At the same time,they reaffirm the irreplaceable value of primary forests as biodiversity refuges and highlight the need for landscape-level conservation strategies that integrate both intact primary and structurally enriched managed forests.展开更多
In this paper,we focus on the channel estimation for multi-user MIMO-OFDM systems in rich scattering environments.We find that channel sparsity in the delay-angle domain is severely compromised in rich scattering envi...In this paper,we focus on the channel estimation for multi-user MIMO-OFDM systems in rich scattering environments.We find that channel sparsity in the delay-angle domain is severely compromised in rich scattering environments,so that most existing compressed sensing(CS)based techniques can harvest a very limited gain(if any)in reducing the channel estimation overhead.To address the problem,we propose the learning-based turbo message passing(LTMP)algorithm.Instead of exploiting the channel sparsity,LTMP is able to efficiently extract the channel feature via deep learning as well as to exploit the channel continuity in the frequency domain via block-wise linear modelling.More specifically,as a component of LTMP,we develop a multi-scale parallel dilated convolutional neural network(MPDCNN),which leverages frequency-space channel correlation in different scales for channel denoising.We evaluate the LTMP’s performance in MIMO-OFDM channels using the 3rd generation partnership project(3GPP)clustered delay line(CDL)channel models.Simulation results show that the proposed channel estimation method has more than 5 dB power gain than the existing algorithms when the normalized mean-square error of the channel estimation is-20 dB.The proposed algorithm also exhibits strong robustness in various environments.展开更多
As the gentle glow of the tropical sunset dripped in through the cabin door,Yogyakarta greeted us with a warming breeze,rustling foliage,and vibrant hum of Indonesian and Javanese.While wrestling with our luggage acro...As the gentle glow of the tropical sunset dripped in through the cabin door,Yogyakarta greeted us with a warming breeze,rustling foliage,and vibrant hum of Indonesian and Javanese.While wrestling with our luggage across the hallways,we scanned the scene excitedly,meeting the curious gazes of locals adorned in colorful batiks and hijabs.That was my first memory of Yogyakarta,one of the richest cities in culture and history in Indonesia.展开更多
Determining the pattern and mechanisms of species richness distribution at large spatial scales has been one of the core objectives in the field of ecology and biogeography.Although climate and soil effects on terrest...Determining the pattern and mechanisms of species richness distribution at large spatial scales has been one of the core objectives in the field of ecology and biogeography.Although climate and soil effects on terrestrial ecosystems are well-documented,largescale patterns in wetlands are poorly understood due to their unique hydrological processes and vegetation types.Here,we explored the pattern of plant species richness of Carex-dominated wetlands and its influencing mechanism in China based on a national field vegetation survey at 120 sites.Results showed that the community type and plant species richness of Carex-dominated wetlands differed significantly among different climate zones in China.The hierarchical partitioning analysis showed that community type and environmental context(spatial location,water regime,climate and soil conditions)together explained 41%of the variations in plant species richness,and community type had the greatest influence on species richness.Partial Least Squares Path Modeling result showed that plant species richness was directly affected by community type,climate factors,soil properties and water regime.Soil properties and water regime also indirectly affected plant species richness by directly affecting community type.These findings help us understand the pattern of plant diversity distribution in wetlands at large spatial scales and design effective conservation strategies for these valuable sedge meadow wetlands in a changing environment.展开更多
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
基金supported by the National Science and Technology Major Program for Noncommunicable Chronic Diseases(2023ZD0503500)the National Natural Science Foundation of China(82030102,12126602,91857118)+1 种基金the Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences(2021-I2M-1-010,2019-I2M-2-003)the National High Level Hospital Clinical Research Funding(2022-GSP-GG-1,2022-GSP-GG-2)。
文摘Objective Evidence suggests that depleted gut microbialα-diversity is associated with hypertension;however,whether metabolic markers affect this relationship remains unknown.We aimed to determine the potential metabolites mediating the associations ofα-diversity with blood pressure(BP)and BP variability(BPV).Methods Metagenomics and plasma targeted metabolomics were conducted on 523 Chinese participants from the MetaSalt study.The 24-hour,daytime,and nighttime BP and BPV were calculated based on ambulatory BP measurements.Linear mixed models were used to characterize the relationships betweenα-diversity(Shannon and Chao1 index)and BP indices.Mediation analyses were performed to assess the contribution of metabolites to the observed associations.The influence of key metabolites on hypertension was further evaluated in a prospective cohort of 2,169 participants.Results Gut microbial richness(Chao1)was negatively associated with 24-hour systolic BP,daytime systolic BP,daytime diastolic BP,24-hour systolic BPV,and nighttime systolic BPV(P<0.05).Moreover,26 metabolites were strongly associated with richness(Bonferroni P<0.05).Among them,four key metabolites(imidazole propionate,2-hydroxy-3-methylbutyric acid,homovanillic acid,and hydrocinnamic acid)mediated the associations between richness and BP indices(proportions of mediating effects:14.1%–67.4%).These key metabolites were also associated with hypertension in the prospective cohort.For example,each 1-standard deviation unit increase in hydrocinnamic acid significantly reduced the risk of prevalent(OR[95%CI]=0.90[0.82,0.99];P=0.03)and incident hypertension(HR[95%CI]=0.83[0.71,0.96];P=0.01).Conclusion Our results suggest that gut microbial richness correlates with lower BP and BPV,and that certain metabolites mediate these associations.These findings provide novel insights into the pathogenesis and prevention of hypertension.
基金supported by the Key Program of National Science of China(Grant No.:42030509 and 42141005)。
文摘The latitudinal diversity gradient(LDG)is one of the most notable biodiversity patterns in biogeography.The metabolic theory of ecology(MTE)explains ecological patterns,including the LDG.However,little is known about whether the LDG remains stable over time as climate warming progresses and whether MTE remains applicable to clarify this pattern.In this study,forest data spanning temperate,subtropical,and tropical zones across China were used to analyze long-term changes in the LDG of tree species over 2005-2020.Based on the MTE framework,spatial scales were considered to assess temperature dependence of typical forest trees species.Our results show that species richness decreased with increasing latitude,and that temperature was the primary driver of this change.Although temperature in China has significantly increased over the past two decades,the LDG of tree species has remained stable.However,there was a decrease in species richness in tropical regions over time.With predictions of the MTE,the logarithm of typical forest tree species richness exhibited negative linear relationships with the inverse of ambient temperature,indicating temperature dependence of species richness.However,the relationship remained stable and was strongly influenced by spatial scale,intensifying as spatial scale increased.The findings emphasize the important role of temperature in shaping the LDG.The effects of spatial scale,in particular,should be considered when biodiversity management plans are developed for future climate change.
基金supported by the National Key Research and Development Program of China(2023YFF0805602)National Natural Science Foundation of China(32225032,32001192,32271597)+1 种基金the Innovation Base Project of Gansu Province(2021YFF0703904)the Science and Technology Program of Gansu Province(24JRRA515,22JR5RA525,23JRRA1157).
文摘Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmental gradients.Particularly,the relative importance(RIV)of different plant life forms in a community and how they vary with environmental variables are still unclear.To fill these gaps,we determined plant diversity of ephemeral plants,annual herbs,perennial herbs,and woody plants from 187 sites across drylands in China.The SR patterns of herbaceous plants,especially perennial herbs,and their RIV in plant communities increased with increasing precipitation and soil nutrient content;however,the RIV of annual herbs was not altered along these gradients.The SR and RIV of ephemeral plants were affected mainly by precipitation seasonality.The SR of woody plants had a unimodal relationship with air temperature and exhibited the highest RIV and SR percentage in plant communities under the harshest environments.An obvious shift emerged in plant community composition,SR and their critical impact factors at 238.5 mm of mean annual precipitation(MAP).In mesic regions(>238.5 mm),herbs were the dominant species,and the SR displayed a relatively slow decreasing rate with increasing aridity,which was mediated mainly by MAP and soil nutrients.In arid regions(<238.5 mm),woody plants were the dominant species,and the SR displayed a relatively fast decreasing rate with increasing aridity,which was mediated mainly by climate variables,especially precipitation.Our findings highlight the importance of comparative life form studies in community structure and biodiversity,as their responses to gradients differed substantially on a large scale.
文摘The entomofauna in the Republic of Congo is very little known. Studies carried out in natural forests are few. It is in this context that this inventory of entomofauna was carried out from April to July 2022 in the Scientific City Forest. The general objective is to contribute to the knowledge of the trapping, mowing and sight hunting;the three types of traps used are: Barber pots, colored plates and aerial traps. This study made it possible to invent 1523 specimens belonging to 106 species, 99 genera, 59 families and 12 orders. The order Diptera is the most abundant and richest in species (47% and 26%). This order is followed by Hymenoptera (23% and 23%). Formicidae (14%) and Calliphoridae (13%) are the most abundant families. The Formicidae family presents the greatest species richness (7%), Calliphora sp and Polyrhachis cyaniventris present the highest specific relative abundance of the entire collection. These preliminary results of the entomofauna of Scientific City constitute a database. However, this study must be continued and extended to other areas of Brazzaville, using other capture techniques and taking into account the seasons.
文摘Insects represent an important taxon for the functioning of ecosystems. They also contribute to human and animal nutrition and are vector agents of several diseases. In Congo-Brazzaville the diversity of entomofauna is very little known. The present study aimed to investigate ponds. The inventory of insects was conducted in ponds Ngatsouéné and Yo, the first one was located in the center of Djambala and the last one was 2 km from the center of the city. The insects were caught with an entomological net from 23rd to 24th December 2012. The study identifies 37 species belonging to 17 families and 7 orders. This entomofauna study showed a high proportion of the Orthoptera order (27.20%). Family Mantidae has the largest species number (13.51%). Mantis sp is the most abundant species (13.51%). This is a database and therefore, should be extended to different aquatic ecosystems of the Department of Plateaux. The results obtained during this study will contribute to the development of a database for the management of entomofauna in Congo.
基金supported by the Natural Science Foundation of Gansu Province(Grant Number:25JRRA749,24JRRA515,24JRRA527)the Fundamental Research Funds for the Central Universities(Grant Number:lzujbky-2022-ct01)+1 种基金JP and JS were supported by Spanish Government grants PID2020115770RB-I,PID2022-140808NB-I00,and TED2021-132627 BeI00funded by MCIN.SLC was supported by NSF award DEB-2423861.
文摘The primary mechanism driving plant species loss after nitrogen(N)addition has been often hypothesized to be asymmetric competition for light,resulting from increased aboveground biomass.However,it is largely unknown whether plants’access to soil water at different depths would affect their responses,fate,and community composition under nitrogen addition.In a semiarid grassland exposed to 8-years of N addition,we measured plant aboveground biomass and diversity under four nitrogen addition rates(0,4,10,and 16 g m2 year1),and evaluated plant use of water across the soil profile using oxygen isotope.Aboveground biomass increased significantly,but diversity and shallow soil-water content decreased,with increasing rate of nitrogen addition.The water isotopic signature for both plant and soil water at the high N rate indicated that Leymus secalinus(a perennial grass)absorbed 7%more water from the subsurface soil layer(20e100 cm)compared to Elymus dahuricus(a perennial grass)and Artemisia annua(an annual forb).L.secalinus thus had a significantly larger biomass and was more abundant than the other two species at the high N rate but did not differ significantly from the other two species under ambient and the low N rate.Species that could use water from deeper soil layers became dominant when water in the shallow layers was insufficient to meet the demands of increased aboveground plant biomass.Our study highlights the importance of water across soil depths as key driver of plant growth and dominance in grasslands under N addition.
文摘Species richness in any area results from the interplay of the processes of speciation,extinction,and dispersal.The relationships between species richness and climate should be considered as an outcome of the effects of climate on speciation,extinction,and dispersal.Diversificationrate represents the balance of speciation and extinction rates over time.Here,I explore diversificationrates in mosses across geographic and climatic gradients worldwide.Specifically,I investigate latitudinal patterns and climatic associations of the mean diversificationrate of mosses at global,hemispheric,and smaller scales.I findthat the mean diversificationrate of mosses is positively correlated with species richness of mosses,increases with decreasing latitude and increasing mean annual temperature and annual precipitation,and is more strongly associated with mean annual temperature than with annual precipitation.These findingsshed light on variation of species richness in mosses across the world.The negative relationship between species richness and latitude and the positive relationship between species richness and mean diversificationrate in mosses suggest that higher moss species richness at lower latitudes might have resulted,at least to some degree,from higher moss diversificationrates at lower latitudes.
基金the Department of Science and Technology(DST)-India for providing a departmental grant to the Department of Biochemistry,Central University of Punjab,Bathinda,India,in the form of a DST-Fund for Improvement of S&T Infrastructure(FIST)grant。
文摘Microplastics (MPs), fluoride (FR), and fungicide mancozeb (MZ) are common contaminants in soil. However, there is no information about the combined impacts of MPs, FR, and MZ on tomato plant growth features in the literature. This study aimed to investigate the effects of combined application of MPs, FR, and MZ (both analytical grade and commercial) on the growth and development of tomato plants and metagenomics of rhizosphere soil. A pot experiment was set up in an artificial greenhouse with two sets of treatments. One set was the combined application of MPs, FR, and analytical grade MZ (B2) and a control without the application of MPs, FR, and MZ (W2), and the other set was the combined application of MPs, FR, and commercial MZ (B3) and a control without the application of MPs, FR, and MZ (W3). No detrimental effects of MPs, FR, and MZ were detected on the growth parameters of tomato plants, including the number of leaves and chlorophyll concentration. However, tomato roots showed knot and nodulation-type structures, and metabolomic profiling revealed that combined exposure to MPs, FR, and MZ profoundly reprogrammed the primary metabolism in tomato roots, with marked alterations in carbohydrate and amino acid pathways. Metagenome whole genome sequencing showed that the B2 and B3 treatments profoundly affected soil microbial community composition, diversity, gene abundances, and functional gene variations compared to W2 and W3. Proteobacteria became the dominating phylum in B2 and B3, causing a significant shift in the microbiome. Its abundance soared to 66.7% in B2 and 75.4% in B3, compared to only 35.9% in W2 and 28.9% in W3. On the other hand, Actinobacteria decreased significantly from 55.6% in W2 and 63.8% in W3 to 18.1% in B2 and 9.6% in B3. This study highlights the microbial shifts due to combined application of MPs, FR, and MZ, providing evidence for understanding their environmental risks.
基金the Brazilian Coordination for the Improvement of Higher Education Personnel (CAPES) by granting the scholarship (Finance Code 001)supported by the Brazilian National Council for Scientific and Technological Development (CNPq, project number 433828/2018-8,435598/2018-0)+1 种基金the Minas Gerais Research Funding Foundation (FAPEMIG, project number CRA APQ 00929-15)CNPq productivity fellowships
文摘Functional traits are characteristics associated with the growth,reproduction,and survival of individuals.Studying them helps us understand how species traits drive ecosystem functioning.Thus,we evaluated the differences in traits and functional diversity between forest edges and interiors,and how the inclusion of intraspecific trait variation affects the assessment of functional diversity in these habitats.We sampled 10 representative forest patches,and,in each patch,we established five plots on the edge and five inside the forest,collecting leaf functional traits,allometric and wood density for all species.We assessed functional diversity using functional richness(FRic),divergence(FDiv),and dispersion(FDis).To assess the impact of incorporating intraspecific variation when comparing trait values and functional diversity indices,we established two scenarios:one that excludes intraspecific variation and another that includes it.We found that the edge and interior harbor individuals with distinct functional traits that alleviate the inherent stress of each habitat.The edge was also found to be more selective in terms of the range of functional traits,resulting in lower functional diversity.Our findings demonstrated that habitats play an important role in intraspecific trait variation(ITV)and that statistically significant differences between habitats,in relation to traits and functional diversity,were better observed with the inclusion of intraspecific variation.Our study highlights the potential of using natural forest patches to understand the edge effect,regardless of habitat loss.Additionally,we emphasize the importance of incorporating ITV into functional diversity studies,especially those on a smaller scale that incorporate quantitative variables,to better understand and predict ecological patterns.
基金financially supported by the National Key R&D Program of China(No.2023YFB3809500)National Natural Science Foundation of China(Grant No.51931006,52272240 and U22A20118)+2 种基金the Fundamental Research Funds for the Central Universities of China(Xiamen University:No.20720220074)Science and Technology Projects of Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(HRTP-[2022]-22)the“Double-First Class”Foundation of Materials Intelligent Manufacturing Discipline of Xiamen University。
文摘Magnesium-lithium hybrid batteries(MLHBs)have gained increasing attention due to their combined advantages of rapid ion insertion/extraction cathode and magnesium metal anode.Herein,Sn S_(2)-SPAN hybrid cathode with strong C-Sn bond and rich defects is ingeniously constructed to realize Mg^(2+)/Li^(+)co-intercalation.The physical and chemical double-confinement synergistic engineering of sulfurized polyacrylonitrile can suppress the agglomeration of Sn S_(2)nanoparticles and the volume expansion,simultaneously promote charge transfer and enhance structural stability.The introduced abundant sulfur vacancies provide more active sites for Mg^(2+)/Li^(+)co-intercalation.Meanwhile,the beneficial effects of rich sulfur defects and C-Sn bond on enhanced electrochemical properties are further evidenced by density-functional theory(DFT)calculations.Therefore,compared with pristine SnS_(2),SnS_(2)-SPAN cathode displays high specific capacity(218 m Ah g^(-1)at 0.5A g^(-1)over 700 cycles)and ultra-long cycling life(101 m Ah g^(-1)at 5 A g^(-1)up to 28,000 cycles).And a high energy density of 307 Wh kg^(-1)can be realized by the Sn S_(2)-SPAN//Mg pouch cell.Such elaborate and simple design supplies a reference for the exploitation of advanced cathode materials with excellent electrochemical properties for MLHBs.
基金supported by the grant from the State Programs"Grid Mapping of the Flora of Uzbekistan'during 2020–2024"the grant from the State Programs"Creation of the Digital Platform of the Plant World of Central Uzbekistan"during 2025–2029the State Research Project"Taxonomic Revision of Polymorphic Plant Families of the Flora of Uzbekistan"from the Institute of Botany,Academy of Sciences of the Republic of Uzbekistan (A-FA-2021-427)
文摘In floristic research,the grid mapping method is a crucial and highly effective tool for investigating the flora of specific regions.This methodology aids in the collection of comprehensive data,thereby promoting a thorough understanding of regional plant diversity.This paper presents findings from a grid mapping study conducted in the Surkhan-Sherabad botanical-geographic region(SShBGR),acknowledged as one of the major floristic areas in southwestern Uzbekistan.Using an expansive dataset of 14,317 records comprised of herbarium specimens and field diary entries collected from 1897 to 2023,we evaluated the stages and seasonal dynamics of data accumulation,species richness(SR),and collection density(CD)within 5 km×5 km grid cells.We further examined the taxonomic and life form composition of the region's flora.Our analysis revealed that the grid mapping phase(2021–2023)produced a significantly greater volume of specimens and taxonomic diversity compared with other periods(1897–1940,1941–1993,and 1994–2020).Field research spanned 206 grid cells during 2021–2023,resulting in 11,883 samples,including 6469 herbarium specimens and 5414 field records.Overall,fieldwork covered 251 of the 253 grid cells within the SShBGR.Notably,the highest species diversity was documented in the B198 grid cell,recording 160 species.In terms of collection density,the E198 grid cell produced 475 samples.Overall,we identified 1053 species distributed across 439 genera and 78 families in the SShBGR.The flora of this region aligned significantly with the dominant families commonly found in the Holarctic,highlighting vital ecological connections.Among our findings,the Asteraceae family was the most polymorphic,with 147 species,followed by the continually stable and diverse Poaceae,Fabaceae,Brassicaceae,and Amaranthaceae.Besides,our analysis revealed a predominance of therophyte life forms,which constituted 52%(552 species)of the total flora.The findings underscore the necessity for continual data collection efforts to further enhance our understanding of the biodiversity in the SShBGR.The results of this study demonstrated that the application of grid-based mapping in floristic studies proves to be an effective tool for assessing biodiversity and identifying key taxonomic groups.
基金Funding for this research was provided by the TAČR SS06010420the Czech University of Life Sciences Prague(grant no.IGA A_13_23).
文摘Anthropogenic activities have significantly contributed to the loss and fragmentation of primary forests across the globe,which has accelerated biodiversity decline,particularly among highly specialised species dependent on unique forest structures.Nevertheless,comparative studies between primary and managed forests are scarce,despite their importance for effective monitoring and conservation planning.To address this knowledge gap,we conducted a comparative study using a unique dataset of permanent study plots established across some of the best-preserved,mixed-beech primary forests and their adjacent managed counterparts in the Western Carpathian Mountains.We assessed the effects of forest structure and tree age—determined through extensive dendrochronological reconstructions—on contemporary lichen communities.Lichen species richness and the richness of red-listed species were 26%and 50%higher in primary forests than in managed forests,respectively,highlighting the outstanding conservation importance of primary forests.Generalised least squares(GLS)modelling demonstrated that in managed forests,lichen species richness was strongly associated with structural attributes:It increased with maximum tree age and the diameter of standing deadwood,and decreased with higher basal area(BA)of living trees,likely due to reduced understory light.In contrast,no structural variables significantly explained richness in primary forests,likely due to structural saturation and widespread microhabitat availability.Elevation emerged as the sole variable with significant explanatory strength.These findings underscore the critical role of structural complexity in supporting lichen diversity under different management regimes and provide a robust evidence base for promoting elements such as old trees,deadwood—especially large standing deadwood—and reduced canopy density.At the same time,they reaffirm the irreplaceable value of primary forests as biodiversity refuges and highlight the need for landscape-level conservation strategies that integrate both intact primary and structurally enriched managed forests.
基金supported in part by the National Key Research and Development Program of China under Grant 2020YFB1804800.
文摘In this paper,we focus on the channel estimation for multi-user MIMO-OFDM systems in rich scattering environments.We find that channel sparsity in the delay-angle domain is severely compromised in rich scattering environments,so that most existing compressed sensing(CS)based techniques can harvest a very limited gain(if any)in reducing the channel estimation overhead.To address the problem,we propose the learning-based turbo message passing(LTMP)algorithm.Instead of exploiting the channel sparsity,LTMP is able to efficiently extract the channel feature via deep learning as well as to exploit the channel continuity in the frequency domain via block-wise linear modelling.More specifically,as a component of LTMP,we develop a multi-scale parallel dilated convolutional neural network(MPDCNN),which leverages frequency-space channel correlation in different scales for channel denoising.We evaluate the LTMP’s performance in MIMO-OFDM channels using the 3rd generation partnership project(3GPP)clustered delay line(CDL)channel models.Simulation results show that the proposed channel estimation method has more than 5 dB power gain than the existing algorithms when the normalized mean-square error of the channel estimation is-20 dB.The proposed algorithm also exhibits strong robustness in various environments.
文摘As the gentle glow of the tropical sunset dripped in through the cabin door,Yogyakarta greeted us with a warming breeze,rustling foliage,and vibrant hum of Indonesian and Javanese.While wrestling with our luggage across the hallways,we scanned the scene excitedly,meeting the curious gazes of locals adorned in colorful batiks and hijabs.That was my first memory of Yogyakarta,one of the richest cities in culture and history in Indonesia.
基金Under the auspices of National Key Research and Development Program of China(No.2023YFF1305800)National Natural Science Foundation of China(No.42494820,U23A2004,42077070)Youth Innovation Promotion Association Chinese Academy of Sciences(No.2019234,2020237)。
文摘Determining the pattern and mechanisms of species richness distribution at large spatial scales has been one of the core objectives in the field of ecology and biogeography.Although climate and soil effects on terrestrial ecosystems are well-documented,largescale patterns in wetlands are poorly understood due to their unique hydrological processes and vegetation types.Here,we explored the pattern of plant species richness of Carex-dominated wetlands and its influencing mechanism in China based on a national field vegetation survey at 120 sites.Results showed that the community type and plant species richness of Carex-dominated wetlands differed significantly among different climate zones in China.The hierarchical partitioning analysis showed that community type and environmental context(spatial location,water regime,climate and soil conditions)together explained 41%of the variations in plant species richness,and community type had the greatest influence on species richness.Partial Least Squares Path Modeling result showed that plant species richness was directly affected by community type,climate factors,soil properties and water regime.Soil properties and water regime also indirectly affected plant species richness by directly affecting community type.These findings help us understand the pattern of plant diversity distribution in wetlands at large spatial scales and design effective conservation strategies for these valuable sedge meadow wetlands in a changing environment.
基金funded by Gorgan University of Agricultural Sciences and Natural Resources(grant number 9318124503).
文摘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.
