Background:Soil fungi play crucial roles in ecosystem functions.However,how snow cover change associated with winter warming affects soil fungal communities remains unclear in the Tibetan forest.Methods:We conducted a...Background:Soil fungi play crucial roles in ecosystem functions.However,how snow cover change associated with winter warming affects soil fungal communities remains unclear in the Tibetan forest.Methods:We conducted a snow manipulation experiment to explore immediate and legacy effects of snow exclusion on soil fungal community diversity and composition in a spruce forest on the eastern Tibetan Plateau.Soil fungal communities were performed by the high throughput sequencing of gene-fragments.Results:Ascomycota and Basidiomycota were the two dominant fungal phyla and Archaeorhizomyces,Aspergillus and Amanita were the three most common genera across seasons and snow manipulations.Snow exclusion did not affect the diversity and structure of soil fungal community in both snow-covered and snow-free seasons.However,the relative abundance of some fungal communities was different among seasons.Soil fungal groups were correlated with environmental factors(i.e.,temperature and moisture)and soil biochemical variables(i.e.,ammonium and enzyme).Conclusions:These results suggest that the season-driven variations had stronger impacts on soil fungal community than short-term snow cover change.Such findings may have important implications for soil microbial processes in Tibetan forests experiencing significant decreases in snowfall.展开更多
Climate warming has been more pronounced in the Arctic than elsewhere, resulting in a recent rapid glacial retreat. Over 85% of the Almajallojekna glacier has disappeared over the last 115 years and it is one of the f...Climate warming has been more pronounced in the Arctic than elsewhere, resulting in a recent rapid glacial retreat. Over 85% of the Almajallojekna glacier has disappeared over the last 115 years and it is one of the fastest retreating glaciers in Sweden. In 2011 and 2012, at 18 sites in the vicinity of the remaining glacier network, we sampled arthropods and related the species richness, abundance and proportion of herbivores to altitude （ranging from 824 to 1,524 m.a.s.1.） and the age of the site （ranging from 0 to 〉 115 years）. Temperature was measured at six sites and the average annual air temperature ranged from -3.7℃ to 1.1℃. In total, we recorded 3,705 arthropods from 117 species in nine different taxonomic groups. The most abundant and species-rich group was Coleoptera （1,381 individuals, 41 species） followed by Araneae （1,050 individuals, 15 species） and Macrolepidoptera （732 individuals, 17 species）. Only at lower altitudes did the abundance and species richness of arthropods increase with increasing age of the site. The results were consistent among the studied taxonomic groups and when controlling for sam- piing intensity using two different approaches. The proportion of herbivores decreased with increasing age of the site and with increasing altitude. Clearly, altitude appears more important than the age of the site and, at higher altitudes, abundance, species richness and herbivory are low [Current Zoology 60 （2）： 203-220, 2014].展开更多
Increasing temperatures and variability of precipitation events due to climate change will lead in the future to higher irrigation demands in agroecosystems.However,the use of secondary treated wasterwater(TWW)could h...Increasing temperatures and variability of precipitation events due to climate change will lead in the future to higher irrigation demands in agroecosystems.However,the use of secondary treated wasterwater(TWW)could have consequences for the receiving soil environment and its resident microbial communities.The objective of this study was to characterize the importance of soil properties and habitats to the response of soil bacteria and archaea to irrigation with TWW.Two agricultural soils with contrasting textures(loamy sand or silt loam)and,for each,three variants differing in soil organic carbon and nitrogen,as generated by long-term fertilization,were analyzed.For each of these six soils,prokaryotic communities from two habitats,i.e.,root-free bulk soil and the rhizosphere of developing cucumber plants in the greenhouse,were characterized.Communities were analyzed by the quantity and diversity of their polymerase chain reaction(PCR)-amplified 16S rRNA genes.To account for TWW-associated nutrient effects,potable water(PW)served as a control.Amplicon sequence analysis showed that prokaryotic communities mainly consisted of bacteria(99.8%).Upon irrigation,regardless of the water quality,prokaryotic diversity declined,p H increased,and no bacterial growth was detected in bulk soil.In contrast,the growth of cucumbers was stimulated by TWW,indicating that plants were the main beneficiaries.Moreover,strong responses were seen in the rhizosphere,suggesting an indirect effect of TWW by altered rhizodepositions.The main bacterial responders to TWW were Proteobacteria,Bacteroidetes,Actinobacteria,and Planctomycetes.Changes in bacterial communities due to TWW were less pronounced in all variants of the silt loam,indicating the importance of clay and soil organic carbon for buffering effects of TWW on soil bacterial communities.Hence,soil organic carbon and soil texture are important parameters that need to be considered when applying TWW in agriculture.展开更多
Background:Forests perform various important ecosystem functions that contribute to ecosystem services.In many parts of the world,forest management has shifted from a focus on timber production to multi-purpose forest...Background:Forests perform various important ecosystem functions that contribute to ecosystem services.In many parts of the world,forest management has shifted from a focus on timber production to multi-purpose forestry,combining timber production with the supply of other forest ecosystem services.However,it is unclear which forest types provide which ecosystem services and to what extent forests primarily managed for timber already supply multiple ecosystem services.Based on a comprehensive dataset collected across 150 forest plots in three regions differing in management intensity and species composition,we develop models to predict the potential supply of 13 ecosystem services.We use those models to assess the level of multifunctionality of managed forests at the national level using national forest inventory data.Results:Looking at the potential supply of ecosystem services,we found trade-offs(e.g.between both bark beetle control or dung decomposition and both productivity or soil carbon stocks)as well as synergies(e.g.for temperature regulation,carbon storage and culturally interesting plants)across the 53 most dominant forest types in Germany.No single forest type provided all ecosystem services equally.Some ecosystem services showed comparable levels across forest types(e.g.decomposition or richness of saprotrophs),while others varied strongly,depending on forest structural attributes(e.g.phosphorous availability or cover of edible plants)or tree species composition(e.g.potential nitrification activity).Variability in potential supply of ecosystem services was only to a lesser extent driven by environmental conditions.However,the geographic variation in ecosystem function supply across Germany was closely linked with the distribution of main tree species.Conclusions:Our results show that forest multifunctionality is limited to subsets of ecosystem services.The importance of tree species composition highlights that a lack of multifunctionality at the stand level can be compensated by managing forests at the landscape level,when stands of complementary forest types are combined.These results imply that multi-purpose forestry should be based on a variety of forest types requiring coordinated planning across larger spatial scales.展开更多
Aims Functional traits are supposed to play an important role in deter-mining the colonization success of new species into established communities.short-term experimental studies have documented higher resistance of m...Aims Functional traits are supposed to play an important role in deter-mining the colonization success of new species into established communities.short-term experimental studies have documented higher resistance of more diverse grasslands against coloni-zation by new species.However,little is known about which traits colonizers should have to successfully invade diverse plant communities in the longer term and how community his-tory may modify the resistance of diverse communities against colonization.Methods In a grassland biodiversity experiment(Jena Experiment)established with different species richness(s;1,2,4,8 and 16)and functional group(Fg)number and composition(1 to 4;legumes,grasses,small herbs,tall herbs),we studied colonization of naturally dispersed species in split-plots(i)with different duration of weeding(never weeded,weeded for 3 or 6 years and then un-weeded for 1 year)and(ii)with different duration of colonization(7 years,4 years and 1 year after cessation of weeding).Important Findingsresistance against colonization by new species declined with increased duration of weeding(on average 13,17 and 22 col-onizer species in 1-,4-and 7-year-old communities,respec-tively).Communities established at low diversity accumulated more colonizer species with a longer duration of weeding than more diverse communities.Duration of colonization had only small effects on the number of colonizer species.Colonizers with early successional traits,i.e.annual life cycle,reproduction by seeds,small seeds,long-lived seeds and an earlier start of a longer flowering period,were favoured in species-poor newly established experimental plant communities(short duration of weeding)and early after cessation of weeding(short duration of colonization).a change from early-to mid-successional traits,i.e.taller growth,perennial life cycle,vegetative reproduction,characterized colonization at increased plant diversity and in communities with legumes or without grasses.legume absence/grass presence and increased duration of weeding led to a shift in colonizer strategies from rapid nutrient uptake and cycling(higher specific leaf area)to nutrient retention and symbiotic N2 fixation.our study shows that non-random trait spectra of naturally dispersed colonizers encompass trade-offs between different functions(reproduction,persistence,growth)reflected in a change from early-to mid-successional traits at increasing plant diversity,with a longer duration of weeding and a longer time of colonization.展开更多
Interspecific plant-soil feedback(PSF)-the influence of soil conditioned by one plant species on another-is key to ecosystem processes but remains challenging to predict due to complex factors like species origin and ...Interspecific plant-soil feedback(PSF)-the influence of soil conditioned by one plant species on another-is key to ecosystem processes but remains challenging to predict due to complex factors like species origin and phylogenetic relatedness.These aspects are underexplored,limiting our understanding of the mechanisms driving PSFs and their broader implications for ecosystem functioning and species coexistence.To shed light on the role of plant species origin and phylogenetic distance in interspecific PSFs,we conducted a greenhouse experiment with 10 native responding species and soils conditioned by 10 native and 10 exotic species resulting in 20 species pairs.These pairs represented a range of phylogenetic distances between both species,spanning up to 270 million years of evolutionary history since their last common ancestor.Conditioning by both native and exotic species reduced biomass production,with stronger inhibition observed for native-conditioned soils.Native-conditioned soils also exhibited lower phosphorus levels,higher basal and specific respiration,and greater cation exchange capacity,base saturation,and magnesium content compared to exotic-conditioned soils.Contrary to expectations,phylogenetic distance did not influence PSFs,regardless of conditioning species origin.Our findings suggest that co-evolution drives native plants to foster microbial communities with low carbon-use efficiency,highlighting soil biota’s critical role in PSFs.This advances our understanding of interactions between plant species origin and microbial communities and underlines the importance of microbial management for promoting native species and controlling invasives.The lack of phylogenetic distance effects aligns with prior studies,indicating evolutionary relatedness alone does not reliably predict PSF outcomes.展开更多
Aims Changing biodiversity can affect ecosystem functioning.However,the role of genetic diversity within species,relative to the one of species diversity,has hardly been addressed.Methods To address the effects of bot...Aims Changing biodiversity can affect ecosystem functioning.However,the role of genetic diversity within species,relative to the one of species diversity,has hardly been addressed.Methods To address the effects of both genetic diversity and species diversity during the important stage of early tree life,we used eight seed families(SF)taken from each of 12 evergreen and deciduous tree species of subtropical forest to perform a factorial experiment.We established 264 communities of 16 trees each.Each community had a species diversity of either one or four species and a genetic diversity of either one,two or four SF per species.We measured plant survival,growth rate,final biomass and herbivory 20 months after sowing.Important Findings Species differed from each other in biomass,growth rate,herbivory and survival(P<0.001).Deciduous species tended to have much higher biomass(P<0.1)and experienced higher herbivory(P<0.05)than evergreen species.Species diversity affected the performance of different species differently(species diversity by species interaction,P<0.001 for all variables but survival).Biomass differed between SF and increasing genetic diversity from one to two,and from two to four,SF per species increased biomass for some species and decreased it for others(P<0.001).Our study showed pronounced species-specific responses of early tree performance to species diversity and less pronounced responses to genetic diversity.These species-specific responses suggest feedbacks of species diversity and genetic diversity on future species composition.展开更多
Aims Species diversity and genetic diversity may be affected in parallel by similar environmental drivers.However,genetic diversity may also be affected independently by habitat characteristics.We aim at disentangling...Aims Species diversity and genetic diversity may be affected in parallel by similar environmental drivers.However,genetic diversity may also be affected independently by habitat characteristics.We aim at disentangling relationships between genetic diversity,species diversity and habitat characteristics of woody species in subtropical forest.Methods We studied 11 dominant tree and shrub species in 27 plots in Gutianshan,China,and assessed their genetic diversity(A_(r))and population differentiation(F′_(ST))with microsatellite markers.We tested if Ar and population specific F′_(ST) were correlated to local species diversity and plot characteristics.Multi-model inference and model averaging were used to determine the relative importance of each predictor.Additionally,we tested for isolation-by-distance(IBD)and isolation-by-elevation by regressing pairwise F′_(ST) against pairwise spatial and elevational distances.Important Findings Genetic diversity was not related to species diversity for any of the study species.Thus,our results do not support joint effects of habitat characteristics on these two levels of biodiversity.Instead,genetic diversity in two understory shrubs,Rhododendron simsii and Vaccinium carlesii,was affected by plot age with decreasing genetic diversity in successionally older plots.Population differentiation increased with plot age in R.simsii and Lithocarpus glaber.This shows that succession can reduce genetic diversity within,and increase genetic diversity between populations.Furthermore,we found four cases of IBD and two cases of isolation-by-elevation.The former indicates inefficient pollen and seed dispersal by animals whereas the latter might be due to phenological asynchronies.These patterns indicate that succession can affect genetic diversity without parallel effects on species diversity and that gene flow in a continuous subtropical forest can be restricted even at a local scale.展开更多
Adaptive evolution along geographic gradients of climatic conditions is suggested to facilitate the spread of invasive plant species,leading to clinal variation among populations in the introduced range.We investigate...Adaptive evolution along geographic gradients of climatic conditions is suggested to facilitate the spread of invasive plant species,leading to clinal variation among populations in the introduced range.We investigated whether adaptation to climate is also involved in the invasive spread of an ornamental shrub,Buddleja davidii,across western and central Europe.Methods We combined a common garden experiment,replicated in three climatically different central European regions,with reciprocal transplantation to quantify genetic differentiation in growth and reproductive traits of 20 invasive B.davidii populations.Additionally,we compared compensatory regrowth among populations after clipping of stems to simulate mechanical damage.Important Findings Our results do not provide evidence for clinal variation among invasive B.davidii populations:populations responded similarly to the different environments,and trait values were not correlated to climatic conditions or geographic coordinates of their home sites.Moreover,we did not detect differences in the compensatory ability of populations.We suppose that the invasive spread of B.davidii has been facilitated by phenotypic plasticity rather than by adaptation to climate and that continent-wide shuffling of cultivars due to horticultural trade may have limited local adaptation so far.展开更多
Aims Genetic variation in plant traits represents the raw material for future adaptive evolution.Its extent can be estimated as heritability based on the performance of experimental plants of known relatedness,such as...Aims Genetic variation in plant traits represents the raw material for future adaptive evolution.Its extent can be estimated as heritability based on the performance of experimental plants of known relatedness,such as maternal half-sib seed families.While there is considerable heritability information for herbaceous plants and commercially important trees,little is known for woody species of natural subtropical forest.Moreover,it is open whether heritability is higher for species with r-or K-strategies,for more common species with larger distribution ranges than for rarer ones,or for populations closer to the centres of distributional ranges.Methods For 14 woody species in Chinese subtropical forest,we collected 13-38 maternal seed families,assessed seed size,grew replicates of each seed family in one more and one less benign nursery environment and measured stem diameter and plant height after 7 months.Important findings For the different species,plants grew 1.8-8.1 times taller in the more benign environment.For all 14 species,variation between seed families(and thus heritability)was significant(with very few exceptions at the P<0.001 level)for seed size and for stem diameter and plant height in both nurseries.Moreover,significant seed family by nursery interactions for stem diameter and plant height for all species(P<0.001)indicated significant heritability for plasticity in these traits.Multiple regression analysis suggests that heritabilities were higher for species with higher age at reproduction and higher wood density(traits indicating a K strategy)but also for species with higher specific leaf area(a trait rather indicating an r strategy).Furthermore,heritabilities were higher for species with larger range sizes,while there was no significant relationship between heritabilities and the distance of the study area to the range margins of our study species.In conclusion,the detected large heritability estimates suggest considerable potential for the evolution of plant performance and its plasticity for trees of subtropical forest.Moreover,our study shows that the simple method of comparing plants of different maternal seed families is valuable to address evolutionary ecological questions for so far understudied species.展开更多
Aims The dispersal of pollen and seeds is spatially restricted and may vary among plant populations because of varying biotic interactions,population histories or abiotic conditions.Because gene dispersal is spatially...Aims The dispersal of pollen and seeds is spatially restricted and may vary among plant populations because of varying biotic interactions,population histories or abiotic conditions.Because gene dispersal is spatially restricted,it will eventually result in the development of spatial genetic structure(SGS),which in turn can allow insights into gene dispersal processes.Here,we assessed the effect of habitat characteristics like population density and community structure on small-scale SGS and estimate historical gene dispersal at different spatial scales.Methods In a set of 12 populations of the subtropical understory shrub Ardisia crenata,we assessed genetic variation at 7 microsatellite loci within and among populations.We investigated small-scale genetic structure with spatial genetic autocorrelation statistics and heterogeneity tests and estimated gene dispersal distances based on population differentiation and on within-population SGS.SGS was related to habitat characteristics by multiple regression.Important Findings The populations showed high genetic diversity(He=0.64)within populations and rather strong genetic differentiation(F#ST=0.208)among populations,following an isolation-by-distance pattern,which suggests that populations are in gene flow–drift equilibrium.Significant SGS was present within populations(mean Sp=0.027).Population density and species diversity had a joint effect on SGS with low population density and high species diversity leading to stronger small-scale SGS.Estimates of historical gene dispersal from between-population differentiation and from within-population SGS resulted in similar values between 4.8 and 22.9 m.The results indicate that local-ranged pollen dispersal and inefficient long-distance seed dispersal,both affected by population density and species diversity,contributed to the genetic population structure of the species.We suggest that SGS in shrubs is more similar to that of herbs than to trees and that in communities with high species diversity gene flow is more restricted than at low species diversity.This may represent a process that retards the development of a positive species diversity–genetic diversity relationship.展开更多
Aims Positive plant diversity-ecosystem function relations are ultimately driven by variation in functional traits among individuals that form a community.To date,research has largely focused on the role of species di...Aims Positive plant diversity-ecosystem function relations are ultimately driven by variation in functional traits among individuals that form a community.To date,research has largely focused on the role of species diversity for ecosystem functioning.However,substantial intraspecific trait variation is common and a significant part of this variation caused by genetic differences among individuals.Here,we studied the relative importance of species diversity and seed family(SF)diversity within species for growth and herbivory in experimental subtropical tree assemblages.Methods In 2010,we set up a field experiment in subtropical China,using four species from the local species pool.Trees were raised from seeds,with seeds from the same mother tree forming an SF.We established 23 plots containing one or four species(species diversity treatment)and one or four SFs per species(SF diversity treatment).Tree growth(stem diameter,plant height and crown expansion)and herbivory(percentage leaf loss due to leaf chewers)were monitored annually from 2011 to 2013.Important findings Tree species richness promoted growth but had no effect on herbivory.In contrast,SF diversity reduced growth and increased herbivory but only so in species mixtures.Most of the observed effects were time dependent,with the largest effect found in 2013.Our results suggest that biodiversity can affect plant performance directly via tree species-species interactions,or context dependent,via potential effects on inter-trophic interactions.Two important conclusions should be drawn from our findings.Firstly,in future studies regarding biodiversity and ecosystem functioning(BEF)relationships,intraspecific genetic diversity should be given similar weight as species diversity as it has often been neglected and its effects are not well understood.Secondly,we demonstrate opposite effects of biodiversity among and within species,stressing the importance to consider the effects of multiple levels of biodiversity simultaneously.展开更多
An important mechanism promoting species coexistence is conspecific negative density dependence(CNDD),which inhibits conspecific neighbors by accumulating host-specific enemies near adult trees.Natural enemies may be ...An important mechanism promoting species coexistence is conspecific negative density dependence(CNDD),which inhibits conspecific neighbors by accumulating host-specific enemies near adult trees.Natural enemies may be genotype-specific and regulate offspring dynamics more strongly than non-offspring,which is often neglected due to the difficulty in ascertaining genetic relatedness.Here,we investigated whether offspring and non-offspring of a dominant species,Castanopsis eyrei,suffered from different strength of CNDD based on parentage assignment in a subtropical forest.We found decreased recruitment efficiency(proxy of survival probability)of offspring compared with non-offspring near adult trees during the seedling-sapling transition,suggesting genotype-dependent interactions drive tree demographic dynamics.Furthermore,the genetic similarity between individuals of same cohort decreased in late life history stages,indicating genetic-relatedness-dependent tree mortality throughout ontogeny.Our results demonstrate that within-species genetic relatedness significantly affects the strength of CNDD,implying genotype-specific natural enemies may contribute to population dynamics in natural forests.展开更多
This article provides morphological descriptions and illustrations of microfungi associated with the invasive weed,Chro-molaena odorata,which were mainly collected in northern Thailand.Seventy-seven taxa distributed i...This article provides morphological descriptions and illustrations of microfungi associated with the invasive weed,Chro-molaena odorata,which were mainly collected in northern Thailand.Seventy-seven taxa distributed in ten orders,23 families(of which Neomassarinaceae is new),12 new genera(Chromolaenicola,Chromolaenomyces,Longiappendispora,Pseudocapulatispora,Murichromolaenicola,Neoophiobolus,Paraleptospora,Pseudoroussoella,Pseudostaurosphaeria,Pseudothyridariella,Setoarthopyrenia,Xenoroussoella),47 new species(Aplosporella chromolaenae,Arthrinium chromolae-nae,Chromolaenicola chiangraiensis,C.lampangensis,C.nanensis,C.thailandensis,Chromolaenomyces appendiculatus,Diaporthe chromolaenae,Didymella chromolaenae,Dyfrolomyces chromolaenae,Leptospora chromolaenae,L.phraeana,Longiappendispora chromolaenae,Memnoniella chromolaenae,Montagnula chiangraiensis,M.chromolaenae,M.chromo-laenicola,M.thailandica,Murichromolaenicola chiangraiensis,M.chromolaenae,Muyocopron chromolaenae,M.chromo-laenicola,Neomassarina chromolaenae,Neoophiobolus chromolaenae,Neopyrenochaeta chiangraiensis,N.chromolaenae,N.thailandica,N.triseptatispora,Nigrograna chromolaenae,Nothophoma chromolaenae,Paraleptospora chromolaenae,P.chromolaenicola,Patellaria chromolaenae,Pseudocapulatispora longiappendiculata,Pseudoroussoella chromolaenae,Pseudostaurosphaeria chromolaenae,P.chromolaenicola,Pseudothyridariella chromolaenae,Pyrenochaetopsis chromolae-nae,Rhytidhysteron chromolaenae,Setoarthopyrenia chromolaenae,Sphaeropsis chromolaenicola,Tremateia chiangraiensis,T.chromolaenae,T.thailandensis,Xenoroussoella triseptata,Yunnanensis chromolaenae),12 new host records,three new taxonomic combinations(Chromolaenicola siamensis,Pseudoroussoella elaeicola,Pseudothyridariella mahakashae),and two reference specimens(Torula chromolaenae,T.fici)are described and illustrated.Unlike some other hosts,e.g.bamboo(Poaceae)and Pandanaceae,the dominant group of fungi on Siam weed were Dothideomycetes.Only 15 species previously recorded from northern Thailand were found in this study.Most of the taxa are likely to have jumped hosts from surrounding plants and are unlikely to be a specialist to Siam weed.Most fungal families found on Siam weed had divergence estimates with stem ages in the Cretaceous,which coincided with the expected origin of the host family(Asteraceae).This further indicates that the species have jumped hosts,as it is unlikely that the taxa on the alien Siam weed came from the Americas with its host.They may,however,have jumped from other Asteraceae hosts.In a preliminary screening 40(65%)of the 62 species tested showed antimicrobial activity and thus,the fungi associated with C.odorata may be promising sources of novel bioactive compound discovery.We provide a checklist of fungi associated with C.odorata based on the USDA Systematic Mycology and Microbiology Laboratory(SMML)database,relevant literature and our study.In total,130 taxa(116 identified and 14 unidentified species)are distributed in 20 orders,48 families and 85 genera.Pseudocercospora is the most commonly encountered genus on Siam weed.展开更多
Background:Changes in foliar nitrogen(N)and phosphorus(P)stoichiometry play important roles in predicting the efects of global change on ecosystem structure and function.However,there is substantial debate on the efec...Background:Changes in foliar nitrogen(N)and phosphorus(P)stoichiometry play important roles in predicting the efects of global change on ecosystem structure and function.However,there is substantial debate on the efects of P addition on foliar N and P stoichiometry,particularly under diferent levels of N addition.Thus,we conducted a global meta-analysis to investigate how N addition alters the efects of P addition on foliar N and P stoichiometry across different rates and durations of P addition and plant growth types based on more than 1150 observations.Results:We found that P addition without N addition increased foliar N concentrations,whereas P addition with N addition had no efect.The positive efects of P addition on foliar P concentrations were greater without N addition than with N addition.Additionally,the efects of P addition on foliar N,P and N:P ratios varied with the rate and duration of P addition.In particular,short-term or low-dose P addition with and without N addition increased foliar N concentration,and the positive efects of short-term or low-dose P addition on foliar P concentrations were greater without N addition than with N addition.The responses of foliar N and P stoichiometry of evergreen plants to P addition were greater without N addition than with N addition.Moreover,regardless of N addition,soil P availability was more efective than P resorption efciency in predicting the changes in foliar N and P stoichiometry in response to P addition.Conclusions:Our results highlight that increasing N deposition might alter the response of foliar N and P stoichiometry to P addition and demonstrate the important efect of the experimental environment on the results.These results advance our understanding of the response of plant nutrient use efciency to P addition with increasing N deposition.展开更多
基金funded by the National Natural Science Foundation of China(Nos.31700542,32071745,31870602,31800519 and 31901295)Program of Sichuan Excellent Youth Sci-Tech Foundation(No.2020JDJQ0052)the National Key Research and Development Program of China(Nos.2016YFC0502505 and 2017YFC0505003)。
文摘Background:Soil fungi play crucial roles in ecosystem functions.However,how snow cover change associated with winter warming affects soil fungal communities remains unclear in the Tibetan forest.Methods:We conducted a snow manipulation experiment to explore immediate and legacy effects of snow exclusion on soil fungal community diversity and composition in a spruce forest on the eastern Tibetan Plateau.Soil fungal communities were performed by the high throughput sequencing of gene-fragments.Results:Ascomycota and Basidiomycota were the two dominant fungal phyla and Archaeorhizomyces,Aspergillus and Amanita were the three most common genera across seasons and snow manipulations.Snow exclusion did not affect the diversity and structure of soil fungal community in both snow-covered and snow-free seasons.However,the relative abundance of some fungal communities was different among seasons.Soil fungal groups were correlated with environmental factors(i.e.,temperature and moisture)and soil biochemical variables(i.e.,ammonium and enzyme).Conclusions:These results suggest that the season-driven variations had stronger impacts on soil fungal community than short-term snow cover change.Such findings may have important implications for soil microbial processes in Tibetan forests experiencing significant decreases in snowfall.
文摘Climate warming has been more pronounced in the Arctic than elsewhere, resulting in a recent rapid glacial retreat. Over 85% of the Almajallojekna glacier has disappeared over the last 115 years and it is one of the fastest retreating glaciers in Sweden. In 2011 and 2012, at 18 sites in the vicinity of the remaining glacier network, we sampled arthropods and related the species richness, abundance and proportion of herbivores to altitude （ranging from 824 to 1,524 m.a.s.1.） and the age of the site （ranging from 0 to 〉 115 years）. Temperature was measured at six sites and the average annual air temperature ranged from -3.7℃ to 1.1℃. In total, we recorded 3,705 arthropods from 117 species in nine different taxonomic groups. The most abundant and species-rich group was Coleoptera （1,381 individuals, 41 species） followed by Araneae （1,050 individuals, 15 species） and Macrolepidoptera （732 individuals, 17 species）. Only at lower altitudes did the abundance and species richness of arthropods increase with increasing age of the site. The results were consistent among the studied taxonomic groups and when controlling for sam- piing intensity using two different approaches. The proportion of herbivores decreased with increasing age of the site and with increasing altitude. Clearly, altitude appears more important than the age of the site and, at higher altitudes, abundance, species richness and herbivory are low [Current Zoology 60 （2）： 203-220, 2014].
基金financially supported by the German Federal Ministry for Food and Agriculture (BMEL) based on the decision of the Parliament of the Federal Republic of Germany (No. 813IL01).
文摘Increasing temperatures and variability of precipitation events due to climate change will lead in the future to higher irrigation demands in agroecosystems.However,the use of secondary treated wasterwater(TWW)could have consequences for the receiving soil environment and its resident microbial communities.The objective of this study was to characterize the importance of soil properties and habitats to the response of soil bacteria and archaea to irrigation with TWW.Two agricultural soils with contrasting textures(loamy sand or silt loam)and,for each,three variants differing in soil organic carbon and nitrogen,as generated by long-term fertilization,were analyzed.For each of these six soils,prokaryotic communities from two habitats,i.e.,root-free bulk soil and the rhizosphere of developing cucumber plants in the greenhouse,were characterized.Communities were analyzed by the quantity and diversity of their polymerase chain reaction(PCR)-amplified 16S rRNA genes.To account for TWW-associated nutrient effects,potable water(PW)served as a control.Amplicon sequence analysis showed that prokaryotic communities mainly consisted of bacteria(99.8%).Upon irrigation,regardless of the water quality,prokaryotic diversity declined,p H increased,and no bacterial growth was detected in bulk soil.In contrast,the growth of cucumbers was stimulated by TWW,indicating that plants were the main beneficiaries.Moreover,strong responses were seen in the rhizosphere,suggesting an indirect effect of TWW by altered rhizodepositions.The main bacterial responders to TWW were Proteobacteria,Bacteroidetes,Actinobacteria,and Planctomycetes.Changes in bacterial communities due to TWW were less pronounced in all variants of the silt loam,indicating the importance of clay and soil organic carbon for buffering effects of TWW on soil bacterial communities.Hence,soil organic carbon and soil texture are important parameters that need to be considered when applying TWW in agriculture.
基金funded through the project‘Bio Holz’(grant no.01LC1323A)in the funding program‘Research for the Implementation of the National Biodiversity Strategy(F&U NBS)’by the German Federal Ministry for Education and Research(BMBF)and the German Federal Agency for Nature Conservation(Bf N)with funds provided by the German Federal Ministry for the Environment,Nature Conservation,Building and Nuclear Safety(BMUB)supported by the DFG Priority Program 1374‘Infrastructure-Biodiversity-Exploratories’。
文摘Background:Forests perform various important ecosystem functions that contribute to ecosystem services.In many parts of the world,forest management has shifted from a focus on timber production to multi-purpose forestry,combining timber production with the supply of other forest ecosystem services.However,it is unclear which forest types provide which ecosystem services and to what extent forests primarily managed for timber already supply multiple ecosystem services.Based on a comprehensive dataset collected across 150 forest plots in three regions differing in management intensity and species composition,we develop models to predict the potential supply of 13 ecosystem services.We use those models to assess the level of multifunctionality of managed forests at the national level using national forest inventory data.Results:Looking at the potential supply of ecosystem services,we found trade-offs(e.g.between both bark beetle control or dung decomposition and both productivity or soil carbon stocks)as well as synergies(e.g.for temperature regulation,carbon storage and culturally interesting plants)across the 53 most dominant forest types in Germany.No single forest type provided all ecosystem services equally.Some ecosystem services showed comparable levels across forest types(e.g.decomposition or richness of saprotrophs),while others varied strongly,depending on forest structural attributes(e.g.phosphorous availability or cover of edible plants)or tree species composition(e.g.potential nitrification activity).Variability in potential supply of ecosystem services was only to a lesser extent driven by environmental conditions.However,the geographic variation in ecosystem function supply across Germany was closely linked with the distribution of main tree species.Conclusions:Our results show that forest multifunctionality is limited to subsets of ecosystem services.The importance of tree species composition highlights that a lack of multifunctionality at the stand level can be compensated by managing forests at the landscape level,when stands of complementary forest types are combined.These results imply that multi-purpose forestry should be based on a variety of forest types requiring coordinated planning across larger spatial scales.
基金Fund for Jena Experiment:German Science Foundation(FOR 456)additional support:Max Planck SocietyFriedrich Schiller University of Jena and coordinated by W.W.Weisser.
文摘Aims Functional traits are supposed to play an important role in deter-mining the colonization success of new species into established communities.short-term experimental studies have documented higher resistance of more diverse grasslands against coloni-zation by new species.However,little is known about which traits colonizers should have to successfully invade diverse plant communities in the longer term and how community his-tory may modify the resistance of diverse communities against colonization.Methods In a grassland biodiversity experiment(Jena Experiment)established with different species richness(s;1,2,4,8 and 16)and functional group(Fg)number and composition(1 to 4;legumes,grasses,small herbs,tall herbs),we studied colonization of naturally dispersed species in split-plots(i)with different duration of weeding(never weeded,weeded for 3 or 6 years and then un-weeded for 1 year)and(ii)with different duration of colonization(7 years,4 years and 1 year after cessation of weeding).Important Findingsresistance against colonization by new species declined with increased duration of weeding(on average 13,17 and 22 col-onizer species in 1-,4-and 7-year-old communities,respec-tively).Communities established at low diversity accumulated more colonizer species with a longer duration of weeding than more diverse communities.Duration of colonization had only small effects on the number of colonizer species.Colonizers with early successional traits,i.e.annual life cycle,reproduction by seeds,small seeds,long-lived seeds and an earlier start of a longer flowering period,were favoured in species-poor newly established experimental plant communities(short duration of weeding)and early after cessation of weeding(short duration of colonization).a change from early-to mid-successional traits,i.e.taller growth,perennial life cycle,vegetative reproduction,characterized colonization at increased plant diversity and in communities with legumes or without grasses.legume absence/grass presence and increased duration of weeding led to a shift in colonizer strategies from rapid nutrient uptake and cycling(higher specific leaf area)to nutrient retention and symbiotic N2 fixation.our study shows that non-random trait spectra of naturally dispersed colonizers encompass trade-offs between different functions(reproduction,persistence,growth)reflected in a change from early-to mid-successional traits at increasing plant diversity,with a longer duration of weeding and a longer time of colonization.
基金supported by iDiv,funded by the German Research Foundation(DFG-FZT 118,202548816).
文摘Interspecific plant-soil feedback(PSF)-the influence of soil conditioned by one plant species on another-is key to ecosystem processes but remains challenging to predict due to complex factors like species origin and phylogenetic relatedness.These aspects are underexplored,limiting our understanding of the mechanisms driving PSFs and their broader implications for ecosystem functioning and species coexistence.To shed light on the role of plant species origin and phylogenetic distance in interspecific PSFs,we conducted a greenhouse experiment with 10 native responding species and soils conditioned by 10 native and 10 exotic species resulting in 20 species pairs.These pairs represented a range of phylogenetic distances between both species,spanning up to 270 million years of evolutionary history since their last common ancestor.Conditioning by both native and exotic species reduced biomass production,with stronger inhibition observed for native-conditioned soils.Native-conditioned soils also exhibited lower phosphorus levels,higher basal and specific respiration,and greater cation exchange capacity,base saturation,and magnesium content compared to exotic-conditioned soils.Contrary to expectations,phylogenetic distance did not influence PSFs,regardless of conditioning species origin.Our findings suggest that co-evolution drives native plants to foster microbial communities with low carbon-use efficiency,highlighting soil biota’s critical role in PSFs.This advances our understanding of interactions between plant species origin and microbial communities and underlines the importance of microbial management for promoting native species and controlling invasives.The lack of phylogenetic distance effects aligns with prior studies,indicating evolutionary relatedness alone does not reliably predict PSF outcomes.
文摘Aims Changing biodiversity can affect ecosystem functioning.However,the role of genetic diversity within species,relative to the one of species diversity,has hardly been addressed.Methods To address the effects of both genetic diversity and species diversity during the important stage of early tree life,we used eight seed families(SF)taken from each of 12 evergreen and deciduous tree species of subtropical forest to perform a factorial experiment.We established 264 communities of 16 trees each.Each community had a species diversity of either one or four species and a genetic diversity of either one,two or four SF per species.We measured plant survival,growth rate,final biomass and herbivory 20 months after sowing.Important Findings Species differed from each other in biomass,growth rate,herbivory and survival(P<0.001).Deciduous species tended to have much higher biomass(P<0.1)and experienced higher herbivory(P<0.05)than evergreen species.Species diversity affected the performance of different species differently(species diversity by species interaction,P<0.001 for all variables but survival).Biomass differed between SF and increasing genetic diversity from one to two,and from two to four,SF per species increased biomass for some species and decreased it for others(P<0.001).Our study showed pronounced species-specific responses of early tree performance to species diversity and less pronounced responses to genetic diversity.These species-specific responses suggest feedbacks of species diversity and genetic diversity on future species composition.
基金German Science Foundation(DFG FOR 891/2,Du 404/3-2 to W.D.).
文摘Aims Species diversity and genetic diversity may be affected in parallel by similar environmental drivers.However,genetic diversity may also be affected independently by habitat characteristics.We aim at disentangling relationships between genetic diversity,species diversity and habitat characteristics of woody species in subtropical forest.Methods We studied 11 dominant tree and shrub species in 27 plots in Gutianshan,China,and assessed their genetic diversity(A_(r))and population differentiation(F′_(ST))with microsatellite markers.We tested if Ar and population specific F′_(ST) were correlated to local species diversity and plot characteristics.Multi-model inference and model averaging were used to determine the relative importance of each predictor.Additionally,we tested for isolation-by-distance(IBD)and isolation-by-elevation by regressing pairwise F′_(ST) against pairwise spatial and elevational distances.Important Findings Genetic diversity was not related to species diversity for any of the study species.Thus,our results do not support joint effects of habitat characteristics on these two levels of biodiversity.Instead,genetic diversity in two understory shrubs,Rhododendron simsii and Vaccinium carlesii,was affected by plot age with decreasing genetic diversity in successionally older plots.Population differentiation increased with plot age in R.simsii and Lithocarpus glaber.This shows that succession can reduce genetic diversity within,and increase genetic diversity between populations.Furthermore,we found four cases of IBD and two cases of isolation-by-elevation.The former indicates inefficient pollen and seed dispersal by animals whereas the latter might be due to phenological asynchronies.These patterns indicate that succession can affect genetic diversity without parallel effects on species diversity and that gene flow in a continuous subtropical forest can be restricted even at a local scale.
基金Deutsche Bundesstiftung Umwelt(20004/705 to S.K.E.).
文摘Adaptive evolution along geographic gradients of climatic conditions is suggested to facilitate the spread of invasive plant species,leading to clinal variation among populations in the introduced range.We investigated whether adaptation to climate is also involved in the invasive spread of an ornamental shrub,Buddleja davidii,across western and central Europe.Methods We combined a common garden experiment,replicated in three climatically different central European regions,with reciprocal transplantation to quantify genetic differentiation in growth and reproductive traits of 20 invasive B.davidii populations.Additionally,we compared compensatory regrowth among populations after clipping of stems to simulate mechanical damage.Important Findings Our results do not provide evidence for clinal variation among invasive B.davidii populations:populations responded similarly to the different environments,and trait values were not correlated to climatic conditions or geographic coordinates of their home sites.Moreover,we did not detect differences in the compensatory ability of populations.We suppose that the invasive spread of B.davidii has been facilitated by phenotypic plasticity rather than by adaptation to climate and that continent-wide shuffling of cultivars due to horticultural trade may have limited local adaptation so far.
基金the consortium of BEF-China(www.bef-china.de)for the excellent intercultural and scientific team spiritthe German Science Foundation DFG for funding.
文摘Aims Genetic variation in plant traits represents the raw material for future adaptive evolution.Its extent can be estimated as heritability based on the performance of experimental plants of known relatedness,such as maternal half-sib seed families.While there is considerable heritability information for herbaceous plants and commercially important trees,little is known for woody species of natural subtropical forest.Moreover,it is open whether heritability is higher for species with r-or K-strategies,for more common species with larger distribution ranges than for rarer ones,or for populations closer to the centres of distributional ranges.Methods For 14 woody species in Chinese subtropical forest,we collected 13-38 maternal seed families,assessed seed size,grew replicates of each seed family in one more and one less benign nursery environment and measured stem diameter and plant height after 7 months.Important findings For the different species,plants grew 1.8-8.1 times taller in the more benign environment.For all 14 species,variation between seed families(and thus heritability)was significant(with very few exceptions at the P<0.001 level)for seed size and for stem diameter and plant height in both nurseries.Moreover,significant seed family by nursery interactions for stem diameter and plant height for all species(P<0.001)indicated significant heritability for plasticity in these traits.Multiple regression analysis suggests that heritabilities were higher for species with higher age at reproduction and higher wood density(traits indicating a K strategy)but also for species with higher specific leaf area(a trait rather indicating an r strategy).Furthermore,heritabilities were higher for species with larger range sizes,while there was no significant relationship between heritabilities and the distance of the study area to the range margins of our study species.In conclusion,the detected large heritability estimates suggest considerable potential for the evolution of plant performance and its plasticity for trees of subtropical forest.Moreover,our study shows that the simple method of comparing plants of different maternal seed families is valuable to address evolutionary ecological questions for so far understudied species.
基金German Science Foundation(DFG FOR 891/1Du 404/3 to W.D.)is highly acknowledged.
文摘Aims The dispersal of pollen and seeds is spatially restricted and may vary among plant populations because of varying biotic interactions,population histories or abiotic conditions.Because gene dispersal is spatially restricted,it will eventually result in the development of spatial genetic structure(SGS),which in turn can allow insights into gene dispersal processes.Here,we assessed the effect of habitat characteristics like population density and community structure on small-scale SGS and estimate historical gene dispersal at different spatial scales.Methods In a set of 12 populations of the subtropical understory shrub Ardisia crenata,we assessed genetic variation at 7 microsatellite loci within and among populations.We investigated small-scale genetic structure with spatial genetic autocorrelation statistics and heterogeneity tests and estimated gene dispersal distances based on population differentiation and on within-population SGS.SGS was related to habitat characteristics by multiple regression.Important Findings The populations showed high genetic diversity(He=0.64)within populations and rather strong genetic differentiation(F#ST=0.208)among populations,following an isolation-by-distance pattern,which suggests that populations are in gene flow–drift equilibrium.Significant SGS was present within populations(mean Sp=0.027).Population density and species diversity had a joint effect on SGS with low population density and high species diversity leading to stronger small-scale SGS.Estimates of historical gene dispersal from between-population differentiation and from within-population SGS resulted in similar values between 4.8 and 22.9 m.The results indicate that local-ranged pollen dispersal and inefficient long-distance seed dispersal,both affected by population density and species diversity,contributed to the genetic population structure of the species.We suggest that SGS in shrubs is more similar to that of herbs than to trees and that in communities with high species diversity gene flow is more restricted than at low species diversity.This may represent a process that retards the development of a positive species diversity–genetic diversity relationship.
基金German Science Foundation(DFG FOR 891/2,Du 404/3-2 to W.D.)is highly acknowledged.
文摘Aims Positive plant diversity-ecosystem function relations are ultimately driven by variation in functional traits among individuals that form a community.To date,research has largely focused on the role of species diversity for ecosystem functioning.However,substantial intraspecific trait variation is common and a significant part of this variation caused by genetic differences among individuals.Here,we studied the relative importance of species diversity and seed family(SF)diversity within species for growth and herbivory in experimental subtropical tree assemblages.Methods In 2010,we set up a field experiment in subtropical China,using four species from the local species pool.Trees were raised from seeds,with seeds from the same mother tree forming an SF.We established 23 plots containing one or four species(species diversity treatment)and one or four SFs per species(SF diversity treatment).Tree growth(stem diameter,plant height and crown expansion)and herbivory(percentage leaf loss due to leaf chewers)were monitored annually from 2011 to 2013.Important findings Tree species richness promoted growth but had no effect on herbivory.In contrast,SF diversity reduced growth and increased herbivory but only so in species mixtures.Most of the observed effects were time dependent,with the largest effect found in 2013.Our results suggest that biodiversity can affect plant performance directly via tree species-species interactions,or context dependent,via potential effects on inter-trophic interactions.Two important conclusions should be drawn from our findings.Firstly,in future studies regarding biodiversity and ecosystem functioning(BEF)relationships,intraspecific genetic diversity should be given similar weight as species diversity as it has often been neglected and its effects are not well understood.Secondly,we demonstrate opposite effects of biodiversity among and within species,stressing the importance to consider the effects of multiple levels of biodiversity simultaneously.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB31000000)the National Key Research and Development Program of China(2017YFA0605103)funded by the US National Science Foundation(NSF DEB-2029997)。
文摘An important mechanism promoting species coexistence is conspecific negative density dependence(CNDD),which inhibits conspecific neighbors by accumulating host-specific enemies near adult trees.Natural enemies may be genotype-specific and regulate offspring dynamics more strongly than non-offspring,which is often neglected due to the difficulty in ascertaining genetic relatedness.Here,we investigated whether offspring and non-offspring of a dominant species,Castanopsis eyrei,suffered from different strength of CNDD based on parentage assignment in a subtropical forest.We found decreased recruitment efficiency(proxy of survival probability)of offspring compared with non-offspring near adult trees during the seedling-sapling transition,suggesting genotype-dependent interactions drive tree demographic dynamics.Furthermore,the genetic similarity between individuals of same cohort decreased in late life history stages,indicating genetic-relatedness-dependent tree mortality throughout ontogeny.Our results demonstrate that within-species genetic relatedness significantly affects the strength of CNDD,implying genotype-specific natural enemies may contribute to population dynamics in natural forests.
基金Ausana Mapook was financially supported by Research and Researchers for Industry Program(RRI)PHD57I0012,Thailand and the German Academic Exchange Service(DAAD)for a joint TRF-DAAD(PPP 2017–2018)academic exchange grant to Kevin D.Hyde and Marc Stadler.Kevin D.Hyde thanks to the 2019 high-end foreign expert introduction plan to Kunming Institute of Botany(granted by the Ministry of Science and Technology of the People’s Republic of China,Grant Number G20190139006)Thailand Research grants entitled Biodiversity,phylogeny and role of fungal endophytes on above parts of Rhizophora apiculata and Nypa fruticans(Grant No:RSA5980068)+1 种基金the future of specialist fungi in a changing climate:baseline data for generalist and specialist fungi associated with ants,Rhododendron species and Dracaena species(Grant No:DBG6080013)Impact of climate change on fungal diversity and biogeography in the Greater Mekong Subregion(Grant No:RDG6130001).
文摘This article provides morphological descriptions and illustrations of microfungi associated with the invasive weed,Chro-molaena odorata,which were mainly collected in northern Thailand.Seventy-seven taxa distributed in ten orders,23 families(of which Neomassarinaceae is new),12 new genera(Chromolaenicola,Chromolaenomyces,Longiappendispora,Pseudocapulatispora,Murichromolaenicola,Neoophiobolus,Paraleptospora,Pseudoroussoella,Pseudostaurosphaeria,Pseudothyridariella,Setoarthopyrenia,Xenoroussoella),47 new species(Aplosporella chromolaenae,Arthrinium chromolae-nae,Chromolaenicola chiangraiensis,C.lampangensis,C.nanensis,C.thailandensis,Chromolaenomyces appendiculatus,Diaporthe chromolaenae,Didymella chromolaenae,Dyfrolomyces chromolaenae,Leptospora chromolaenae,L.phraeana,Longiappendispora chromolaenae,Memnoniella chromolaenae,Montagnula chiangraiensis,M.chromolaenae,M.chromo-laenicola,M.thailandica,Murichromolaenicola chiangraiensis,M.chromolaenae,Muyocopron chromolaenae,M.chromo-laenicola,Neomassarina chromolaenae,Neoophiobolus chromolaenae,Neopyrenochaeta chiangraiensis,N.chromolaenae,N.thailandica,N.triseptatispora,Nigrograna chromolaenae,Nothophoma chromolaenae,Paraleptospora chromolaenae,P.chromolaenicola,Patellaria chromolaenae,Pseudocapulatispora longiappendiculata,Pseudoroussoella chromolaenae,Pseudostaurosphaeria chromolaenae,P.chromolaenicola,Pseudothyridariella chromolaenae,Pyrenochaetopsis chromolae-nae,Rhytidhysteron chromolaenae,Setoarthopyrenia chromolaenae,Sphaeropsis chromolaenicola,Tremateia chiangraiensis,T.chromolaenae,T.thailandensis,Xenoroussoella triseptata,Yunnanensis chromolaenae),12 new host records,three new taxonomic combinations(Chromolaenicola siamensis,Pseudoroussoella elaeicola,Pseudothyridariella mahakashae),and two reference specimens(Torula chromolaenae,T.fici)are described and illustrated.Unlike some other hosts,e.g.bamboo(Poaceae)and Pandanaceae,the dominant group of fungi on Siam weed were Dothideomycetes.Only 15 species previously recorded from northern Thailand were found in this study.Most of the taxa are likely to have jumped hosts from surrounding plants and are unlikely to be a specialist to Siam weed.Most fungal families found on Siam weed had divergence estimates with stem ages in the Cretaceous,which coincided with the expected origin of the host family(Asteraceae).This further indicates that the species have jumped hosts,as it is unlikely that the taxa on the alien Siam weed came from the Americas with its host.They may,however,have jumped from other Asteraceae hosts.In a preliminary screening 40(65%)of the 62 species tested showed antimicrobial activity and thus,the fungi associated with C.odorata may be promising sources of novel bioactive compound discovery.We provide a checklist of fungi associated with C.odorata based on the USDA Systematic Mycology and Microbiology Laboratory(SMML)database,relevant literature and our study.In total,130 taxa(116 identified and 14 unidentified species)are distributed in 20 orders,48 families and 85 genera.Pseudocercospora is the most commonly encountered genus on Siam weed.
基金supported by the National Natural Science Foundation of China(Grant Nos.31870602,31901295,and 32071745)the Program of Sichuan Excellent Youth Sci-Tech Foundation(20JCQN0145)+2 种基金the Chinese Postdoctoral Science Foundation(2020M673278)the CAS“Light of West China”Program(Y8C2021)Chengming You also acknowledges the China Scholarship Council for supporting a Ph.D.programme Grant(201806910030)。
文摘Background:Changes in foliar nitrogen(N)and phosphorus(P)stoichiometry play important roles in predicting the efects of global change on ecosystem structure and function.However,there is substantial debate on the efects of P addition on foliar N and P stoichiometry,particularly under diferent levels of N addition.Thus,we conducted a global meta-analysis to investigate how N addition alters the efects of P addition on foliar N and P stoichiometry across different rates and durations of P addition and plant growth types based on more than 1150 observations.Results:We found that P addition without N addition increased foliar N concentrations,whereas P addition with N addition had no efect.The positive efects of P addition on foliar P concentrations were greater without N addition than with N addition.Additionally,the efects of P addition on foliar N,P and N:P ratios varied with the rate and duration of P addition.In particular,short-term or low-dose P addition with and without N addition increased foliar N concentration,and the positive efects of short-term or low-dose P addition on foliar P concentrations were greater without N addition than with N addition.The responses of foliar N and P stoichiometry of evergreen plants to P addition were greater without N addition than with N addition.Moreover,regardless of N addition,soil P availability was more efective than P resorption efciency in predicting the changes in foliar N and P stoichiometry in response to P addition.Conclusions:Our results highlight that increasing N deposition might alter the response of foliar N and P stoichiometry to P addition and demonstrate the important efect of the experimental environment on the results.These results advance our understanding of the response of plant nutrient use efciency to P addition with increasing N deposition.
