Litter decomposition is key to ecosystem carbon(C)and nutrient cycling,but this process is anticipated to weaken due to projected more extensive and prolonged drought.Yet how litter quality and decomposer community co...Litter decomposition is key to ecosystem carbon(C)and nutrient cycling,but this process is anticipated to weaken due to projected more extensive and prolonged drought.Yet how litter quality and decomposer community complexity regulate decomposition in response to drought is less understood.Here,in a five-year manipulative drought experiment in a Masson pine forest,leaf litter from four subtropical tree species(Quercus griffthii Hook.f.&Thomson ex Miq.,Acacia mangium Willd.,Pinus massoniana Lamb.,Castanopsis hystrix Miq.)representing different qualities was decomposed for 350 d in litterbags of three different mesh sizes(i.e.,0.05,1,and 5 mm),respectively,under natural conditions and a 50%throughfall rain exclusion treatment.Litterbags of increasing mesh sizes discriminate decomposer communities(i.e.,microorganisms,microorganisms and mesofauna,microorganisms and meso-and macrofauna)that access the litter and represent an increasing complexity.The amount of litter C and nitrogen(N)loss,and changes in their ratio(C/N_(loss)),as well as small and medium-sized decomposers including microorganisms,nematodes,and arthropods,were investigated.We found that drought did not affect C and N loss but decreased C/N_(loss)(i.e.,decomposer N use efficiency)of leaf litter irrespective of litter quality and decomposer complexity.However,changes in the C/N_(loss)and the drought effect on C loss were both dependent on litter quality,while drought and decomposer complexity interactively affected litter C and N loss.Increasing decomposer community complexity enhanced litter decomposition and allowing additional access of meso-and macro-fauna to litterbags mitigated the negative drought effect on the microbial-driven decomposition.Furthermore,both the increased diversity and altered trophic structure of nematode due to drought contributed to the mitigation effects via cascading interactions.Our results show that litter quality and soil decomposer community complexity co-drive the effect of drought on litter decomposition.This experimental finding provides a new insight into the mechanisms controlling forest floor C and nutrient cycling under future global change scenarios.展开更多
[Objective]This research aimed to compare arthropod communities in different cruciferous vegetable fields at high mountainous area and provide guidance for pest control. [Method] The main arthropod species in 3 kinds ...[Objective]This research aimed to compare arthropod communities in different cruciferous vegetable fields at high mountainous area and provide guidance for pest control. [Method] The main arthropod species in 3 kinds of erueiferous vegetable fields at high mountainous area were investigated, the composition of arthropod community in different vegetable fields were analyzed. [Result] The main arthropod species in erueiferous vegetables fields at high mountainous area were similar, but had different quantity compositions. The richness was the highest in radish field. [Conclusion] Crop species had great influence on biological community; we should focus on the main pests in the process of pest control.展开更多
Soil fauna have been receiving more and more attention because they play an important role in nutrient cycling.However,there is a lack of information on soil arthropods in the forest-steppe ecotone in the mountainous ...Soil fauna have been receiving more and more attention because they play an important role in nutrient cycling.However,there is a lack of information on soil arthropods in the forest-steppe ecotone in the mountainous region of northern Hebei,which makes it difficult to meet the need of protecting biodiversity in this area.Soil arthropod communities were investigated in the forest-steppe ecotone in northern Hebei province to provide basic information on changes in mountain soil fertility,which could promote the development of soil arthropod communities in mountain ecotones.From the preliminary identification,a total of 7994 individual soil arthropods were collected,which belonged to 25 groups,6 classes and 24 orders.Acarina,Hymenoptera and Collembola were the dominant groups in the ecotone.The number of Acarina was higher than Collembola,and this phenomenon was obviously different from other areas in the same climate zone.The increased abundance of rare groups in the Forest zone with the richer vegetation,higher arthropod abundance and more substantial litter depth,could be interpreted as a reaction to the suitable soil environment and food supply.And these rare groups were sensitive to environmental changes,which could be regarded as biotic indicators for evaluating soil quality.The analysis of community diversity showed that the abundance index (d),the Shannon-Wiener index (H'),the evenness index (J) and the density-group index (DG) were significantly higher in the forest zone,lower in the forest-steppe zone,and lowest in the meadow-steppe zone.Seasonal variations in community composition correlated with changes in average air temperature and precipitation in this ecotone.Groups and individuals of soil arthropod communities in the three zones were present in greater numbers in the middle of the rainy season than in the early or late periods of the rainy season as a whole.At the same time,seasonal changes in soil arthropod communities from different plots were also influenced by habitat condition.展开更多
We report two new three-dimensionally phosphatized microfossils, Cambrolongispina reticulata gen. et sp. nov. and Cambrolongispina glabra gen. et sp. nov., from the middle Cambrian （Series 3, Drumian Stage） at Wangc...We report two new three-dimensionally phosphatized microfossils, Cambrolongispina reticulata gen. et sp. nov. and Cambrolongispina glabra gen. et sp. nov., from the middle Cambrian （Series 3, Drumian Stage） at Wangcun, Yongshun County, western Hunan, South China. They are bivalved arthropods, with thin, pliable, originally chitinous or chitin-calcareous shields （c. 350-517 I1 m long）. The shields are equipped with a pair of antero-dorsal spines. The spines are internally hollow, varying in length from 1/2 of to as long as the shield length in C. reticulata, and uniformly longer than the shield length in C. glabra. The spines of C. reticulata are ornamented with a longitudinal row of conical or blade-shaped denticles along the posterior edge. Cambrolongispina lacks marginal rims, valve lobation and sulci which are diagnostic of the Bradoriida sensu stricto. It also lacks a donblure/duplicature characteristic of phosphatocopids and some bradoriids. It could be related to the Monasteriidae （which may belong to Bradoriida sensu lato）, both characterized by a pair of antero-dorsal spines. Cambrolongispina may have been meiofaunai detritus feeders that lived on or within sediments. The antero-dorsal spines may have been sensory organs to detect nearby predators. The posterior denticles on these spines might have facilitated the sensory function of the spines.展开更多
The Guanshan Fauna is a soft-bodied fauna dominated by arthropods （including trilobites, trilobitoides, Tuzoia, Isoxys, and bradorids） in association with priapulids, brachiopods, anomalocaridids, vetulicoliids, spo...The Guanshan Fauna is a soft-bodied fauna dominated by arthropods （including trilobites, trilobitoides, Tuzoia, Isoxys, and bradorids） in association with priapulids, brachiopods, anomalocaridids, vetulicoliids, sponges, chancellorids, and echinoderms. This paper reports and describes a new arthropod from the yellowish green mudstone at the lower part of the Wulongqing Formation, Canglangpuan Stage, Lower Cambrian in Kunming, Yunnan, China. The stratigraphic and geographic distribution, classification, fossil preservation, life style of this new arthropod and comparisons with other fossil arthropods are also discussed in details. The discovery and research of the non-mineralized arthropod, Guangweicaris Luo, Fu et Hu gen. nov. from the Guanshan Fauna adds new members to the taxonomic list and provides new information to the evolution of early arthropods. Furthermore, this study would shed new light into the ＂Cambrian Explosion＂ and the evolution of early life.展开更多
To study horseshoe crab Limulus polyphemus spawning behavior and migration over a large-spatial extent （〉100 km）, we arrayed fixed station radio receivers throughout Delaware Bay and deployed radio transmitters and...To study horseshoe crab Limulus polyphemus spawning behavior and migration over a large-spatial extent （〉100 km）, we arrayed fixed station radio receivers throughout Delaware Bay and deployed radio transmitters and archival tags on adult horseshoe crabs prior to their spawning season. We tagged and released 160 females and 60 males in 2004 and 217 females in 2005. The array covered approximately 140 km of shoreline. Recapture rates were 〉70% with multi-year recaptures. We categorized adult age by carapace wear. Older females tended to spawn earlier in the season and more frequently than young females, but those tendencies were more apparent in 2004 when spawning overall occurred earlier than in 2005 when spawning was delayed possibly due to decreased water temperatures. Timing of initial spawning within a year was correlated with water temperature. After adjusting for day of first spring tide, the day of In＇st spawning was 4 days earlier for every 1 degree （℃） rise in mean daily water temperature in May. Seventy nine % of spawning occurred during nighttime high tides. Fifty five % of spawning occurred within 3 d of a spring tide, which was slightly higher than the 47% expected if spawning was uniformly distributed regardless of tidal cycle. Within the same spawning season, males and females were observed spawning or intertidally resting at more than one beach separated by 〉5 kin. Between years, most （77%） did not return to spawn at the same beach. Probability of stranding was strongly age dependent for males and females with older adults experiencing higher stranding rates. Horseshoe crabs staging in the shallow waters east of the channel spawned exclusively along the eastern （N J） shoreline, but those staging west of the channel spawned throughout the bay. Overall, several insights emerged from the use of radio telemetry, which advances our understanding of horseshoe crab ecology and will be useful in conserving the Delaware Bay horseshoe crab population and habitats展开更多
Shrub is an important factor on structuring ground arthropod communities in desert ecosystems. In this study, in order to determine how shrubs and their species influence ground arthropod distribution patterns in a sa...Shrub is an important factor on structuring ground arthropod communities in desert ecosystems. In this study, in order to determine how shrubs and their species influence ground arthropod distribution patterns in a sandy desert scrubland dominated by two different shrub species, Calligonum mongolicum and Nitraria sphaerocarpa, the ground arthropods were sampled with pitfall traps during spring, summer and autumn. At the community level, total arthropod abundance was shown to be significantly higher under shrubs than in intershrub bare areas in spring; similar patterns occurred in terms of the richness of arthropod groups in the spring and over three seasons, suggesting season-specific shrub presence effects on arthropod activity. In addition, more arthropods were found under N. sphaerocarpa shrubs than under C. rnongolicum shrubs in autumn, suggesting season-specific effects of shrub species of arthropod activity, whereas more arthropods taxa were captured under C. mongoIicum than N. sphaerocarpa. At the trophic group level, the abundances of predator and herbivore arthropods were significantly greater under shrubs than in intershrub bare habitats, whereas herbivore arthropods were more abundant under N. sphaerocarpa than C. rnongolicum, and an opposite rule was detected for predator arthropods At the family level, the mean abundances of Carabidae, Curculionidae, Gnaphosidae and Lycosidae were significantly higher in the shrub microhabitats than in the intershrub bare habitat, there was no significant difference between habitats on the mean abundances of Formicidae and Tenebrionidae. The study results suggested that shrub presence and shrub species variation are important determinants of ground arthropod assemblages in this desert ecosystem, but the responses of ar- thropods differed among trophic and taxonomic groups.展开更多
Current global warming is particularly pronounced in the Arctic and arthropods are expected to respond rapidly to these changes. Long-term studies of individual arthropod species from the Arctic are, however, virtuall...Current global warming is particularly pronounced in the Arctic and arthropods are expected to respond rapidly to these changes. Long-term studies of individual arthropod species from the Arctic are, however, virtually absent. We examined butterfly specimens collected from yellow pitfall traps over 14 years （1996-2009） at Zackenberg in high-arctic, north-east Greenland. Specimens were previously sorted to the family level. We identified them to the species level and examined long-term species-specific phenological responses to recent summer wanning. Two species were rare in the samples （Polaris fritillary Boloria polaris and Arctic blue Plebejus glandon） and statistical analyses of phenological responses were therefore restricted to the two most abundant species （Arctic fritillary, B. chariclea and Northern clouded yellow Colias hecla）. Our analyses demonstrated a trend towards earlier flight seasons in B. chariclea, but not in C. hecla. The timing of onset, peak and end of the flight season in B. chariclea were closely related to snowmelt, July temperature and their interaction, whereas onset, peak and end of the flight season in C. hecla were only related to timing of snowmelt. The duration of the butterfly flight season was significantly positively related to the temporal overlap with floral resources in both butterfly species. We further demonstrate that yellow pitfall traps are a useful alternative to transect walks for butterfly recording in tundra habitats. More phenological studies of Arctic arthropods should be carded out at the species level and ideally be analysed in context with interacting species to assess how ongoing climate change will affect Arctic biodiversity in the near future [Current Zoology 60 （2）： 243-251, 2014].展开更多
Mountains imply enormous environmental variation, with alpine habitats entailing harsh environ- ments, especially for ectotherms such as lizards. This environmental variability also may imply variation in prey availab...Mountains imply enormous environmental variation, with alpine habitats entailing harsh environ- ments, especially for ectotherms such as lizards. This environmental variability also may imply variation in prey availability. However, little is known about how lizard trophic ecology varies with elevation. In this study, we analyze diet, prey availability, prey selection, and trophic niche width in the lacertid lizard Psammodromus algirus along a 2,200-m elevational gradient in the Sierra Nevada （SE Spain）. The analysis of fecal samples has shown that Orthoptera, Formicidae, Hemiptera, Coleoptera, and Araneae are the main prey, although, according to their abundance in pitfall traps, Formicidae and Coleoptera are rejected by the lizard whereas Orthoptera, Hemiptera, and Araneae are preferred. Prey abundance and diversity increase with elevation and diet subtly varies along with the elevational gradient. The consumption of Coleoptera increases with elevation probably as a consequence of the lizard foraging more in open areas while basking. The electivity for Araneae increases with elevation. Araneae are rejected in the lowlands--where they are rela- tively abundant--whereas, at high elevation, this lizard positively selects them, despite they being less abundant. The lizard trophic niche width expands with elevation due to concomitant greater prey diversity and hence this lizard feeds on more prey types in highlands. Although no sex difference in diet has been found, the trophic niche is broader in females than males. As a whole, alpine lizards show a trophic niche simitar to that found at lower elevat（ons, suggesting that P. algirus is well adapted to the harsh environment found in alpine areas.展开更多
Different microhabitats along dune slope were found to affect the distribution of plant performances and soil properties in desertified ecosystems. However, the ground-active arthropod responses to rainfall-induced du...Different microhabitats along dune slope were found to affect the distribution of plant performances and soil properties in desertified ecosystems. However, the ground-active arthropod responses to rainfall-induced dune microhabitats were largely unknown in desertified regions. At dune top, midslope and bottom, ground-active arthropods were sampled by the method of pitfall traps in addition to the herbaceous and soil measurements during spring, summer and autumn from 2012 to 2013. Ground-active arthropod had a strong dynamics in time, seasonally and yearly in responses to rainfall-induced dune microhabitats and the variations were significant higher than those of soil and herbaceous properties. The abundance distribution of dominant taxa （i.e. Melolonthidae, Carabidae, Glaphyridae, Tenebrionidae and Formicidae families） among dune microhabitats was similar between seasons within the same year, whereas they differed markedly between two sampling years with varying rainfall patterns. A significant （P〈0.05） difference in total abundance, taxa richness and Shannon index among dune microhabitats was found only in certain season time, particularly in 2013; however, no significant （P〉0.05） differences were found among dune microhabitats when averaged on three sampling seasons within the year of either 2012 or 2013. In all, the taxonomical structure differed considerably from the community structure in ground-active arthropod response to rainfall-induced dune microhabitats. The spatial distribution of taxonomical groups among dune microhabitats was significantly affected by inter-annual rainfall changes, whereas that of community structure was affected by both intra- and inter-annual rainfall changes in desertified ecosystems.展开更多
El Soplao outcrop, an Early Cretaceous amber deposit recently discovered in northern Spain （Cantabria）, has been shown to be the largest site of amber with arthropod inclusions that has been found in Spain so far. R...El Soplao outcrop, an Early Cretaceous amber deposit recently discovered in northern Spain （Cantabria）, has been shown to be the largest site of amber with arthropod inclusions that has been found in Spain so far. Relevant data provided herein for biogeochemistry of the amber, palynology, taphonomy and arthropod bioinclusions complement those previously published. This set of data suggests at least two botanical sources for the amber of El Soplao deposit. The first （type A amber） strongly supports a source related to Cheirolepidiaceae, and the second （type B amber） shows non-specific conifer biomarkers. Comparison of molecular composition of type A amber with Frenelopsis leaves （Cheirolepidiaceae） strongly suggests a biochemical affinity and a common botanical origin. A preliminary palynological study indicates a regional high taxonomical diversity, mainly of pteridophyte spores and gymnosperm pollen grains. According to the preliminary palynological data, the region was inhabited by conifer forests adapted to a dry season under a subtropical climate. The abundant charcoalified wood associated with the amber in the same beds is evidence of paleofires that most likely promoted both the resin production and an intensive erosion of the litter, and subsequent great accumulation of amber plus plant cuticles. In addition, for the first time in the fossil record, charcoalified plant fibers as bioinclnsions in amber are reported. Other relevant taphonomic data are the exceptional presence of serpulids and bryozoans on the surfaces of some amber pieces indicating both a long exposure on marine or brackish-water and a mixed assemblage of amber. Lastly, new findings of insect bioiuclusions, some of them uncommon in the fossil record or showing remarkable adaptations, are reported. In conclusion, a documented scenario for the origin of the El Soplao amber outcrop is provided.展开更多
Objective:To determine distribution of arthropods in rice grains obtained from different sources.Methods: Rice samples were randomly collected from public in urban areas,farmers in rice field areas,aborigines in undev...Objective:To determine distribution of arthropods in rice grains obtained from different sources.Methods: Rice samples were randomly collected from public in urban areas,farmers in rice field areas,aborigines in undeveloped areas and retailers in commercial premises.Random samples of rice were taken out from each sample for isolation of arthropods using a modified Berlese Tullgren Funnel Method.Mites were mounted prior to identification; weevils were directly identified.Results:Samples of rice from retailers in commercial premises had the highest infestation by arthropods followed by samples from urbanites,aborigines and rice farmers.Two species of weevils,Sitophilus oryzae(S.oryzae) and Sitophilus granarius(S.granarius),were found.Samples from commercial premises had the least percentage of weevils compared to those collected from domestic premises. Depending on the source of samples,densities of S.granarius and S.oryzae ranges from 11-103 weevils/ kg and 7- 80 weevils/kg,respectively.Important species of mites in stored rice identified were mainly members of the families Cheyletidae,Echimyopodidae,Pyroglyphidae,Saproglyphidae and Tenuipalpidae.Among the species of mites identified were Austroglycyphagus malaysiensis,Cheyletus fortis,Cheyletus malaccensis,Dermatophagoides pteronyssinus,Grammolichus malukuensis and Suidasia pontifica.Average density of most of the mites was less than 40 mites/kg of rice grains.In this study,the highest number of mites in rice samples was recovered from commercial premises,followed by samples from urbanites.Samples from farmers and aborigines contained lesser mites.Conclusion:This study demonstrated the presence of 3 allergenic mite species in rice, i.e A.malaysiensis,D.pteronyssinus and S.pontifica.Weevils,S.oryzae and S.granarius that are known to be allergenic,were also found.展开更多
Tropical forests provide several ecosystem services and functions and support approximately two-thirds of the world’s biodiversity but are seriously threatened by deforestation.Approaches to counteract this menace ha...Tropical forests provide several ecosystem services and functions and support approximately two-thirds of the world’s biodiversity but are seriously threatened by deforestation.Approaches to counteract this menace have revolved around aff orestation with several or a single tree species.We thus investigated how plantation forests with either a single or several tree species infl uenced arthropod taxonomic and community composition using pitfall traps to sample selected groups of epigeal arthropods(Araneae,Coleoptera,Orthoptera and Hymenoptera)and with environmental variables assessed simultaneously.Our results revealed 54 taxonomic groups with signifi cantly higher taxonomic richness,activity density,and diversity in the mixed stands than in the monoculture stands.The significant differences in community composition were mainly driven by families including Lycosidae,Formicidae,Staphylinidae,Scotylidae,Hydrophilidae,Gryllidae and Scarabaeidae and were explained by distinct habitat characteristics(canopy openness,litter depth,deadwood volume,and tree height).While the diverse tree communities and heterogeneous vegetation structure off ered food and habitat resources for diverse arthropod groups,the allelopathic nature coupled with homogenous stand characteristics of the Tectona grandis stands in the monoculture suppressed the growth of understorey vegetation that could otherwise serve as food and habitat resources for arthropods,which might have led to limited activities and diversity of arthropods in the monoculture plantation stands.The fi ndings thus highlight the need to promote mixed tree plantations in degraded tropical areas,especially when restoring biodiversity is the prime management focus.展开更多
Arthropod community structure and diversity were investigated in transgenic insect-resistant hybrid poplar 741 field trial plots, which had five isogenic clones with two genes （Bt. toxin [Cry IAc] and arrowhead prote...Arthropod community structure and diversity were investigated in transgenic insect-resistant hybrid poplar 741 field trial plots, which had five isogenic clones with two genes （Bt. toxin [Cry IAc] and arrowhead proteinase inhibitor [API]） in comparison to control plots. Transgenic poplar clones were investigated according to their insect resistance （high and medium resistant clones）, being systematically probed into varying levels with feeding tests before. Investigations were carded out during three years （2002, 2003 and 2005）. The results indicated that among the basal species, transgenic plants in general had lower amounts of phytophagous insects, and an increased quantity of neutral arthropods such as saprophytic and strolling species. Among the top and intermediate species in transgenic variants, the quantity of predatory natural enemies was increased, while the amount of parasitoid ones was slightly reduced. The arthropod community characteristic indices were analyzed from different aspects in the three variants. It was discovered that, not only the characteristic indices of the whole arthropod community, but also the characteristic indices of the sub-communities （such as natural enemy, pest and neutral arthropods） and the functional groups categorized by their feeding patterns, showed a higher diversity and evenness and a lower dominancy concentration indices in the high-resistant and medium-resistant plots compared with the control. Transgenic poplar 741 showed improved ecological effects both in partial and total aspects. It could be concluded that composition and structure of the arthropod community in plots with transgenic insect-resistant poplar were turned to be more reasonable and itsdiversity and stability was enhanced.展开更多
Objective:To determine distribution of arthropods in processed rice products such as rice flour and rice cereal-based infant food.Methods:Random samples of rice flour and rice cereal-based infant food purchased from c...Objective:To determine distribution of arthropods in processed rice products such as rice flour and rice cereal-based infant food.Methods:Random samples of rice flour and rice cereal-based infant food purchased from commercial outlets were examined for the presence of arthropods using a modified Berlese Tullgren Funnel Method.Mites were mounted prior to identification and weevils were directly identified.Results:For non-expired products, infestation was found in 6.7%of rice flour and none was found in rice cereal-based infant food samples.The arthropods found in the flour samples were Cheyletus spp.,Suidasia pontifica(S. pontifica),Tarsonemus spp.,Tyrophagus putrescentiae(T.putrescentiae),Sitophilus granarius(S. granarius) and Sitophilus oryzae(S.oryzae).Others which cannot be identified were Oribatid and Prostigmatid mites.The most common mites in rice flour were Tarsonemus spp.(69.1%),followed by S.pontifica(18.2%).For expired products,only one sample of rice cereal-based infant food was infested and the infestation was by mites of the family Tydeidae.Conclusions:This study demonstrates the presence of 4 allergenic species of S.pontifica,T.putrescentiae,S.granarius and S.oryzae in rice flour.These arthropods can contribute to the incidence of anaphylaxis upon consumption by atopic individuals.There was no infestation of arthropods in rice cereal-based infant food surveyed except for an expired product in a moderate rusty tin container.展开更多
Quercus rugosa and Q.laurina are species that presents a wide geographical distribution range in temperate forests of Mexico. Oak canopies contain a considerable portion of arthropod diversity and the arthropods fauna...Quercus rugosa and Q.laurina are species that presents a wide geographical distribution range in temperate forests of Mexico. Oak canopies contain a considerable portion of arthropod diversity and the arthropods fauna fulfill a wide variety of ecological roles. We examined the effect of oak species and seasonal changes on some community structure parameters (diversity,composition,similarity,biomass,rare species,and density of arthropod fauna) of canopy arthropods. In total,40 oak canopies were fogged during rainy and dry season. A total of 614 identified arthropod morphospecies were recognized belonging to 22 orders associated with tree canopies. A separation of host tree species during both seasons,suggesting a different community structure on host plants species was demonstrated by the principal component analyses (PCA),therefore,differences between oak species results in phenotypes that structure the composition of the arthropod community. Q.laurina registered the highest densities,diversity index and number of rare species in comparison with Q.rugosa. While arthropod biomass showed an inverse pattern. Trees more close to one another (spatial distance) register a more similar canopy arthropod fauna. This study suggests that the trees of Q.laurina could act as a center of biodiversity by the accumulation of arthropod fauna with a considerable number of rare species,which presents wide ecological roles or is involved in critical processes that maintain forest ecosystems.展开更多
Arthropod communities and epiphytic plants associated with tree canopies have been widely studied and have revealed a great diversity of organisms; however,the community hosted by parasitic plants,such as dwarf mistle...Arthropod communities and epiphytic plants associated with tree canopies have been widely studied and have revealed a great diversity of organisms; however,the community hosted by parasitic plants,such as dwarf mistletoes,remains poorly known.In the coniferous forests of North America,dwarf mistletoe infection（Arceuthobium spp.） significantly damages the health of the forest,causing large financial losses for the forest industry,but it also positively affects diversity,especially of mammals and birds.This study examined the attributes of the arthropod communities associated with two species of dwarf mistletoe [Arceuthobium globosum Hawksw.＆ Wiens and A.vaginatum（Humb.＆ Bonpl.ex Willd.） J.Presl] and their host Pinus hartwegii Lindl.In 2010,in five sites located in Zoquiapan（Central Mexico）,we collected plant tissue from the three species bimonthly.Arthropods were separated from the plant tissue and identified to the finest level possible.We collected 32,059 individuals,for which51 morphospecies were identified,belonging to 15 taxonomic orders; the most abundant orders for the three plants were Prostigmata,Thysanoptera and Homoptera.The community associated with P.hartwegii had the highest value of diversity（H＇= 1.47; A.globosum,H＇= 0.64; A.vaginatum,H＇= 0.68） and species richness（S = 40; A.globosum,S = 30; A.vaginatum,S = 35）; while abundance was significantly higher for the mistletoes（A.globosum,n = 407 individuals/sample; A.vaginatum,n = 536 individuals/sample; P.hartwegii,n = 134 individuals/sample）.Species richness,abundance and diversity were significantly different for the three studied plants,as well for sampling month and the interaction of these two factors（except for diversity）.The results suggest that the canopy of P.hartwegii is an important element in the ecosystem,providing a mosaic of resources and conditions to the associated fauna.We also propose that mistletoes are key species within the forest canopy,as they greatly influence the establishment of diverse organisms,particularly arthropods.展开更多
Biting midges of the genus Culicoides(order Diptera,family Ceratopogonidae)are potential biological vectors for the transmission of certain arboviruses among humans,livestock,and wild animals.This study collected a to...Biting midges of the genus Culicoides(order Diptera,family Ceratopogonidae)are potential biological vectors for the transmission of certain arboviruses among humans,livestock,and wild animals.This study collected a total of 405 Culicoides individuals from seven animal farms located in five counties in the border areas of Yunnan Province,China,and examined the Culicoides species composition and the major arboviruses carried by the Culicoides species.The collected Culicoides were classified into seven species with variable abundances:Culicoides arakawae(5.43%,22/405),Culicoides homotomus(1.23%,5/405),Culicoides obsoletus(19.75%,80/405),Culicoides orientalis(17.28%,70/405),Culicoides oxystoma(29.38%,119/405),Culicoides peregrinus(5.68%,23/405),and Culicoides nipponensis(21.23%,86/405).Among the seven species,C.oxystoma and C.nipponensis were distributed in all the five counties with abundances of 13.33–44.87%and 10.00–46.83%,respectively,suggesting that these were the dominant species of Culicoides widespread on animal farms in the border areas.PCR was used to detect major arboviruses in the collected Culicoides specimens,including bluetongue virus(BTV),Japanese encephalitis virus,Dengue virus,Zika virus,African swine fever virus,and African horse sickness virus.Among the tested viruses,only BTV serotype 1 was tested positive in C.oxystoma specimens collected from a buffalo farm.Culicoides oxystoma was the dominant species on animal farms in the sampled areas,but it has not previously been documented as positive for BTV in China.The current results thus suggest that C.oxystoma could be an important vector for BTV transmission in these border areas,which,however,needs to be confirmed by further comprehensive experiments.Overall,the present study provides the first profile of Culicoides species on animal farms in the China,Vietnam,and Myanmar border areas,establishes the prevalence of arboviruses carried by these Culicoides species,and suggests the vector potential of C.oxystoma species for the transmission of BTV.展开更多
Background: Grit is used by birds mainly for grinding hard food items but can also serve a nutritional role as a source of minerals. Ingestion of grit by birds has been documented primarily in species that feed on see...Background: Grit is used by birds mainly for grinding hard food items but can also serve a nutritional role as a source of minerals. Ingestion of grit by birds has been documented primarily in species that feed on seeds and invertebrates.Although feeding mainly on nectar and small arthropods, hummingbirds also ingest grit, but why they do so is unclear. We quantified the number of grit particles in the stomachs of six species of hummingbirds during an annual cycle in a seasonal ecosystem of West Mexico.Methods: We compared the number of grit particles in the stomachs of different hummingbird species(Mexican Violetear Colibri thalassinus, Amethyst-throated Mountaingem Lampornis amethystinus, White-eared Hummingbird Basilinna leucotis, Rivoli's Hummingbird Eugenes fulgens, Broad-tailed Hummingbird Selasphorus platycercus, and Rufous Hummingbird S. rufus), and between sex and age categories during the different seasons of a year. To deter-mine if grit was used to grind ingested arthropods, we examined the relationships between the number of grit parti-cles, the biomass of arthropods ingested, and their chitin content.Results: Although species did not differ in the number of grit particles in their stomachs, we found that grit was mostly ingested by female individuals, with only one male of one species(Mexican Violetear) presenting grit in its stomach. We also found that female hummingbirds had grit in their stomachs during the rainy and the cold-dry season(June-February) but not during the warm-dry season(March-May). Our analyses revealed no relationship between the number of grit particles and the amount of ingested arthropods and arthropod chitin content. However,high grit consumption was related to wasp ingestion on Mexican Violetears.Conclusions: Our results indicate that grit is used mainly by female hummingbirds. The seasonal variation in the ingestion of grit by female individuals suggests that it can be used to meet mineral requirements related to breed-ing;however, this topic needs further exploration. Additionally, the use of grit was proportionally higher in juvenile individuals, suggesting it is used for grinding arthropods during a period of fast development.展开更多
We applied a multi-taxa approach integrating the co-occurrence of plants,ground beetles,spiders and springtails with soil parameters(temperatures and chemical characteristics)in order to describe the primary successio...We applied a multi-taxa approach integrating the co-occurrence of plants,ground beetles,spiders and springtails with soil parameters(temperatures and chemical characteristics)in order to describe the primary succession along two glacier forelands in the Maritime Alps(Italy),a hotspot of Mediterranean biodiversity.We compared these successions to those from Central Alps:Maritime glacier forelands markedly differ for their higher values of species richness and species turnover.Contrary to our expectation,Maritime glacier forelands follow a‘replacement change model’,like continental succession of Inner Alps and differently from other peripheral successions.We propose that the temperatures along these Mediterranean glacier forelands are warmer than those along other Alpine glacier forelands,which promote the faster species turnover.Furthermore,we found that early and mid successional stages of the investigated glaciers are richer in cold-adapted and endemic species than the later ones:we confirmed that the‘replacement change’model disadvantages pioneer,cold-adapted species.Given the overall correspondence among coldadapted and endemic species,the most threatened in this climate phase,our results raise new concerns about the extinction risk of these species.We also describe supraglacial habitat of Maritime glaciers demonstrating that supraglacial debris represents an environment decoupled from the regional climate and may have an important role as refugium for coldadapted and hygrophilous plant and animal species,whose survival can be threatened by climate change and by a rapid ecological succession in the adjacent forelands.展开更多
基金jointly funded by the National Natural Science Foundation of China(No.31930078)the National Key R&D Program of China(No.2021YFD2200405)+3 种基金Science and Technology Cooperation Projects between governments of China and the European Union(No.2023YFE0105100)the Fundamental Research Funds for ICBR(No.1632021023)Sanya Research Base of ICBR(No.1630032023002)the Scientific and Technological Innovation Team for Qinghai-Tibetan Plateau Research in Southwest Minzu University(No.2024CXTD10)。
文摘Litter decomposition is key to ecosystem carbon(C)and nutrient cycling,but this process is anticipated to weaken due to projected more extensive and prolonged drought.Yet how litter quality and decomposer community complexity regulate decomposition in response to drought is less understood.Here,in a five-year manipulative drought experiment in a Masson pine forest,leaf litter from four subtropical tree species(Quercus griffthii Hook.f.&Thomson ex Miq.,Acacia mangium Willd.,Pinus massoniana Lamb.,Castanopsis hystrix Miq.)representing different qualities was decomposed for 350 d in litterbags of three different mesh sizes(i.e.,0.05,1,and 5 mm),respectively,under natural conditions and a 50%throughfall rain exclusion treatment.Litterbags of increasing mesh sizes discriminate decomposer communities(i.e.,microorganisms,microorganisms and mesofauna,microorganisms and meso-and macrofauna)that access the litter and represent an increasing complexity.The amount of litter C and nitrogen(N)loss,and changes in their ratio(C/N_(loss)),as well as small and medium-sized decomposers including microorganisms,nematodes,and arthropods,were investigated.We found that drought did not affect C and N loss but decreased C/N_(loss)(i.e.,decomposer N use efficiency)of leaf litter irrespective of litter quality and decomposer complexity.However,changes in the C/N_(loss)and the drought effect on C loss were both dependent on litter quality,while drought and decomposer complexity interactively affected litter C and N loss.Increasing decomposer community complexity enhanced litter decomposition and allowing additional access of meso-and macro-fauna to litterbags mitigated the negative drought effect on the microbial-driven decomposition.Furthermore,both the increased diversity and altered trophic structure of nematode due to drought contributed to the mitigation effects via cascading interactions.Our results show that litter quality and soil decomposer community complexity co-drive the effect of drought on litter decomposition.This experimental finding provides a new insight into the mechanisms controlling forest floor C and nutrient cycling under future global change scenarios.
基金Supported by Education Department of Hubei Province(D200512006)~~
文摘[Objective]This research aimed to compare arthropod communities in different cruciferous vegetable fields at high mountainous area and provide guidance for pest control. [Method] The main arthropod species in 3 kinds of erueiferous vegetable fields at high mountainous area were investigated, the composition of arthropod community in different vegetable fields were analyzed. [Result] The main arthropod species in erueiferous vegetables fields at high mountainous area were similar, but had different quantity compositions. The richness was the highest in radish field. [Conclusion] Crop species had great influence on biological community; we should focus on the main pests in the process of pest control.
基金supported by funds from the National Natural Science Foundation of China (30070626)Knowledge Innovation Program of CAS (KSCX2-YW-N-46-11)
文摘Soil fauna have been receiving more and more attention because they play an important role in nutrient cycling.However,there is a lack of information on soil arthropods in the forest-steppe ecotone in the mountainous region of northern Hebei,which makes it difficult to meet the need of protecting biodiversity in this area.Soil arthropod communities were investigated in the forest-steppe ecotone in northern Hebei province to provide basic information on changes in mountain soil fertility,which could promote the development of soil arthropod communities in mountain ecotones.From the preliminary identification,a total of 7994 individual soil arthropods were collected,which belonged to 25 groups,6 classes and 24 orders.Acarina,Hymenoptera and Collembola were the dominant groups in the ecotone.The number of Acarina was higher than Collembola,and this phenomenon was obviously different from other areas in the same climate zone.The increased abundance of rare groups in the Forest zone with the richer vegetation,higher arthropod abundance and more substantial litter depth,could be interpreted as a reaction to the suitable soil environment and food supply.And these rare groups were sensitive to environmental changes,which could be regarded as biotic indicators for evaluating soil quality.The analysis of community diversity showed that the abundance index (d),the Shannon-Wiener index (H'),the evenness index (J) and the density-group index (DG) were significantly higher in the forest zone,lower in the forest-steppe zone,and lowest in the meadow-steppe zone.Seasonal variations in community composition correlated with changes in average air temperature and precipitation in this ecotone.Groups and individuals of soil arthropod communities in the three zones were present in greater numbers in the middle of the rainy season than in the early or late periods of the rainy season as a whole.At the same time,seasonal changes in soil arthropod communities from different plots were also influenced by habitat condition.
基金supported by the National Natural Science Foundation of China (41102003 and J1210006 to ZH41272011 to XS+3 种基金41372015 to DXP)State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences (20132107 to ZH103102 to DXP)the Research Fund for Doctoral Program of High Education (20060001059 to DXP)
文摘We report two new three-dimensionally phosphatized microfossils, Cambrolongispina reticulata gen. et sp. nov. and Cambrolongispina glabra gen. et sp. nov., from the middle Cambrian （Series 3, Drumian Stage） at Wangcun, Yongshun County, western Hunan, South China. They are bivalved arthropods, with thin, pliable, originally chitinous or chitin-calcareous shields （c. 350-517 I1 m long）. The shields are equipped with a pair of antero-dorsal spines. The spines are internally hollow, varying in length from 1/2 of to as long as the shield length in C. reticulata, and uniformly longer than the shield length in C. glabra. The spines of C. reticulata are ornamented with a longitudinal row of conical or blade-shaped denticles along the posterior edge. Cambrolongispina lacks marginal rims, valve lobation and sulci which are diagnostic of the Bradoriida sensu stricto. It also lacks a donblure/duplicature characteristic of phosphatocopids and some bradoriids. It could be related to the Monasteriidae （which may belong to Bradoriida sensu lato）, both characterized by a pair of antero-dorsal spines. Cambrolongispina may have been meiofaunai detritus feeders that lived on or within sediments. The antero-dorsal spines may have been sensory organs to detect nearby predators. The posterior denticles on these spines might have facilitated the sensory function of the spines.
基金This study was supported by the Major Basic Research Project of the Ministry of Science and Technology of China （No. 2002CCA03300） the National Natural Science Foundation of China （No. 40672004）+1 种基金 the National ＂973＂ Project （No. 2006CB806401）the jointproject between the Yunnan Institute of Geological Science and the Shenzhen Palaeontological Museum （No. YIGS- 2006-01）.
文摘The Guanshan Fauna is a soft-bodied fauna dominated by arthropods （including trilobites, trilobitoides, Tuzoia, Isoxys, and bradorids） in association with priapulids, brachiopods, anomalocaridids, vetulicoliids, sponges, chancellorids, and echinoderms. This paper reports and describes a new arthropod from the yellowish green mudstone at the lower part of the Wulongqing Formation, Canglangpuan Stage, Lower Cambrian in Kunming, Yunnan, China. The stratigraphic and geographic distribution, classification, fossil preservation, life style of this new arthropod and comparisons with other fossil arthropods are also discussed in details. The discovery and research of the non-mineralized arthropod, Guangweicaris Luo, Fu et Hu gen. nov. from the Guanshan Fauna adds new members to the taxonomic list and provides new information to the evolution of early arthropods. Furthermore, this study would shed new light into the ＂Cambrian Explosion＂ and the evolution of early life.
基金Support Program, New Jersey Fish Game & Wildlife, and Delaware Department of Natural Resources and Environmental Control
文摘To study horseshoe crab Limulus polyphemus spawning behavior and migration over a large-spatial extent （〉100 km）, we arrayed fixed station radio receivers throughout Delaware Bay and deployed radio transmitters and archival tags on adult horseshoe crabs prior to their spawning season. We tagged and released 160 females and 60 males in 2004 and 217 females in 2005. The array covered approximately 140 km of shoreline. Recapture rates were 〉70% with multi-year recaptures. We categorized adult age by carapace wear. Older females tended to spawn earlier in the season and more frequently than young females, but those tendencies were more apparent in 2004 when spawning overall occurred earlier than in 2005 when spawning was delayed possibly due to decreased water temperatures. Timing of initial spawning within a year was correlated with water temperature. After adjusting for day of first spring tide, the day of In＇st spawning was 4 days earlier for every 1 degree （℃） rise in mean daily water temperature in May. Seventy nine % of spawning occurred during nighttime high tides. Fifty five % of spawning occurred within 3 d of a spring tide, which was slightly higher than the 47% expected if spawning was uniformly distributed regardless of tidal cycle. Within the same spawning season, males and females were observed spawning or intertidally resting at more than one beach separated by 〉5 kin. Between years, most （77%） did not return to spawn at the same beach. Probability of stranding was strongly age dependent for males and females with older adults experiencing higher stranding rates. Horseshoe crabs staging in the shallow waters east of the channel spawned exclusively along the eastern （N J） shoreline, but those staging west of the channel spawned throughout the bay. Overall, several insights emerged from the use of radio telemetry, which advances our understanding of horseshoe crab ecology and will be useful in conserving the Delaware Bay horseshoe crab population and habitats
基金funded by one of National Basic Research Program of China (No. 2013CB429903)National Natural Science Foundation of China (Grant Nos. 41201248 and 31170496)
文摘Shrub is an important factor on structuring ground arthropod communities in desert ecosystems. In this study, in order to determine how shrubs and their species influence ground arthropod distribution patterns in a sandy desert scrubland dominated by two different shrub species, Calligonum mongolicum and Nitraria sphaerocarpa, the ground arthropods were sampled with pitfall traps during spring, summer and autumn. At the community level, total arthropod abundance was shown to be significantly higher under shrubs than in intershrub bare areas in spring; similar patterns occurred in terms of the richness of arthropod groups in the spring and over three seasons, suggesting season-specific shrub presence effects on arthropod activity. In addition, more arthropods were found under N. sphaerocarpa shrubs than under C. rnongolicum shrubs in autumn, suggesting season-specific effects of shrub species of arthropod activity, whereas more arthropods taxa were captured under C. mongoIicum than N. sphaerocarpa. At the trophic group level, the abundances of predator and herbivore arthropods were significantly greater under shrubs than in intershrub bare habitats, whereas herbivore arthropods were more abundant under N. sphaerocarpa than C. rnongolicum, and an opposite rule was detected for predator arthropods At the family level, the mean abundances of Carabidae, Curculionidae, Gnaphosidae and Lycosidae were significantly higher in the shrub microhabitats than in the intershrub bare habitat, there was no significant difference between habitats on the mean abundances of Formicidae and Tenebrionidae. The study results suggested that shrub presence and shrub species variation are important determinants of ground arthropod assemblages in this desert ecosystem, but the responses of ar- thropods differed among trophic and taxonomic groups.
文摘Current global warming is particularly pronounced in the Arctic and arthropods are expected to respond rapidly to these changes. Long-term studies of individual arthropod species from the Arctic are, however, virtually absent. We examined butterfly specimens collected from yellow pitfall traps over 14 years （1996-2009） at Zackenberg in high-arctic, north-east Greenland. Specimens were previously sorted to the family level. We identified them to the species level and examined long-term species-specific phenological responses to recent summer wanning. Two species were rare in the samples （Polaris fritillary Boloria polaris and Arctic blue Plebejus glandon） and statistical analyses of phenological responses were therefore restricted to the two most abundant species （Arctic fritillary, B. chariclea and Northern clouded yellow Colias hecla）. Our analyses demonstrated a trend towards earlier flight seasons in B. chariclea, but not in C. hecla. The timing of onset, peak and end of the flight season in B. chariclea were closely related to snowmelt, July temperature and their interaction, whereas onset, peak and end of the flight season in C. hecla were only related to timing of snowmelt. The duration of the butterfly flight season was significantly positively related to the temporal overlap with floral resources in both butterfly species. We further demonstrate that yellow pitfall traps are a useful alternative to transect walks for butterfly recording in tundra habitats. More phenological studies of Arctic arthropods should be carded out at the species level and ideally be analysed in context with interacting species to assess how ongoing climate change will affect Arctic biodiversity in the near future [Current Zoology 60 （2）： 243-251, 2014].
文摘Mountains imply enormous environmental variation, with alpine habitats entailing harsh environ- ments, especially for ectotherms such as lizards. This environmental variability also may imply variation in prey availability. However, little is known about how lizard trophic ecology varies with elevation. In this study, we analyze diet, prey availability, prey selection, and trophic niche width in the lacertid lizard Psammodromus algirus along a 2,200-m elevational gradient in the Sierra Nevada （SE Spain）. The analysis of fecal samples has shown that Orthoptera, Formicidae, Hemiptera, Coleoptera, and Araneae are the main prey, although, according to their abundance in pitfall traps, Formicidae and Coleoptera are rejected by the lizard whereas Orthoptera, Hemiptera, and Araneae are preferred. Prey abundance and diversity increase with elevation and diet subtly varies along with the elevational gradient. The consumption of Coleoptera increases with elevation probably as a consequence of the lizard foraging more in open areas while basking. The electivity for Araneae increases with elevation. Araneae are rejected in the lowlands--where they are rela- tively abundant--whereas, at high elevation, this lizard positively selects them, despite they being less abundant. The lizard trophic niche width expands with elevation due to concomitant greater prey diversity and hence this lizard feeds on more prey types in highlands. Although no sex difference in diet has been found, the trophic niche is broader in females than males. As a whole, alpine lizards show a trophic niche simitar to that found at lower elevat（ons, suggesting that P. algirus is well adapted to the harsh environment found in alpine areas.
基金supported by the Science Research Foundation of Ningxia Higher Education(NGY2015053)Ningxia Natural Science Foundation(NZ15025)the National Natural Science Foundation of China(41101050)
文摘Different microhabitats along dune slope were found to affect the distribution of plant performances and soil properties in desertified ecosystems. However, the ground-active arthropod responses to rainfall-induced dune microhabitats were largely unknown in desertified regions. At dune top, midslope and bottom, ground-active arthropods were sampled by the method of pitfall traps in addition to the herbaceous and soil measurements during spring, summer and autumn from 2012 to 2013. Ground-active arthropod had a strong dynamics in time, seasonally and yearly in responses to rainfall-induced dune microhabitats and the variations were significant higher than those of soil and herbaceous properties. The abundance distribution of dominant taxa （i.e. Melolonthidae, Carabidae, Glaphyridae, Tenebrionidae and Formicidae families） among dune microhabitats was similar between seasons within the same year, whereas they differed markedly between two sampling years with varying rainfall patterns. A significant （P〈0.05） difference in total abundance, taxa richness and Shannon index among dune microhabitats was found only in certain season time, particularly in 2013; however, no significant （P〉0.05） differences were found among dune microhabitats when averaged on three sampling seasons within the year of either 2012 or 2013. In all, the taxonomical structure differed considerably from the community structure in ground-active arthropod response to rainfall-induced dune microhabitats. The spatial distribution of taxonomical groups among dune microhabitats was significantly affected by inter-annual rainfall changes, whereas that of community structure was affected by both intra- and inter-annual rainfall changes in desertified ecosystems.
基金supported by a scholarship from the Instituto Geologico y Minero de Espana(IGME),an APIF grant of the University of Barcelona,and a FPI grant from the Spanish Ministry of Science and Technology,respectivelya contribution of the IGME Project 491-CANOA 35015"Investigacion cientifica y tecnica de la Cueva de E1 Soplao y su entorno geologico"+1 种基金the projects CGL2008-/01237BTE from the MICINN,CGL2008- 00550/BTE:"Amber of the Cretaceous of Spain:A multidisciplinary study"the ANR Project AMBRACE BLAN07-1-184190
文摘El Soplao outcrop, an Early Cretaceous amber deposit recently discovered in northern Spain （Cantabria）, has been shown to be the largest site of amber with arthropod inclusions that has been found in Spain so far. Relevant data provided herein for biogeochemistry of the amber, palynology, taphonomy and arthropod bioinclusions complement those previously published. This set of data suggests at least two botanical sources for the amber of El Soplao deposit. The first （type A amber） strongly supports a source related to Cheirolepidiaceae, and the second （type B amber） shows non-specific conifer biomarkers. Comparison of molecular composition of type A amber with Frenelopsis leaves （Cheirolepidiaceae） strongly suggests a biochemical affinity and a common botanical origin. A preliminary palynological study indicates a regional high taxonomical diversity, mainly of pteridophyte spores and gymnosperm pollen grains. According to the preliminary palynological data, the region was inhabited by conifer forests adapted to a dry season under a subtropical climate. The abundant charcoalified wood associated with the amber in the same beds is evidence of paleofires that most likely promoted both the resin production and an intensive erosion of the litter, and subsequent great accumulation of amber plus plant cuticles. In addition, for the first time in the fossil record, charcoalified plant fibers as bioinclnsions in amber are reported. Other relevant taphonomic data are the exceptional presence of serpulids and bryozoans on the surfaces of some amber pieces indicating both a long exposure on marine or brackish-water and a mixed assemblage of amber. Lastly, new findings of insect bioiuclusions, some of them uncommon in the fossil record or showing remarkable adaptations, are reported. In conclusion, a documented scenario for the origin of the El Soplao amber outcrop is provided.
基金funded by a grant from the Malaysia Toray Science Foundation.
文摘Objective:To determine distribution of arthropods in rice grains obtained from different sources.Methods: Rice samples were randomly collected from public in urban areas,farmers in rice field areas,aborigines in undeveloped areas and retailers in commercial premises.Random samples of rice were taken out from each sample for isolation of arthropods using a modified Berlese Tullgren Funnel Method.Mites were mounted prior to identification; weevils were directly identified.Results:Samples of rice from retailers in commercial premises had the highest infestation by arthropods followed by samples from urbanites,aborigines and rice farmers.Two species of weevils,Sitophilus oryzae(S.oryzae) and Sitophilus granarius(S.granarius),were found.Samples from commercial premises had the least percentage of weevils compared to those collected from domestic premises. Depending on the source of samples,densities of S.granarius and S.oryzae ranges from 11-103 weevils/ kg and 7- 80 weevils/kg,respectively.Important species of mites in stored rice identified were mainly members of the families Cheyletidae,Echimyopodidae,Pyroglyphidae,Saproglyphidae and Tenuipalpidae.Among the species of mites identified were Austroglycyphagus malaysiensis,Cheyletus fortis,Cheyletus malaccensis,Dermatophagoides pteronyssinus,Grammolichus malukuensis and Suidasia pontifica.Average density of most of the mites was less than 40 mites/kg of rice grains.In this study,the highest number of mites in rice samples was recovered from commercial premises,followed by samples from urbanites.Samples from farmers and aborigines contained lesser mites.Conclusion:This study demonstrated the presence of 3 allergenic mite species in rice, i.e A.malaysiensis,D.pteronyssinus and S.pontifica.Weevils,S.oryzae and S.granarius that are known to be allergenic,were also found.
文摘Tropical forests provide several ecosystem services and functions and support approximately two-thirds of the world’s biodiversity but are seriously threatened by deforestation.Approaches to counteract this menace have revolved around aff orestation with several or a single tree species.We thus investigated how plantation forests with either a single or several tree species infl uenced arthropod taxonomic and community composition using pitfall traps to sample selected groups of epigeal arthropods(Araneae,Coleoptera,Orthoptera and Hymenoptera)and with environmental variables assessed simultaneously.Our results revealed 54 taxonomic groups with signifi cantly higher taxonomic richness,activity density,and diversity in the mixed stands than in the monoculture stands.The significant differences in community composition were mainly driven by families including Lycosidae,Formicidae,Staphylinidae,Scotylidae,Hydrophilidae,Gryllidae and Scarabaeidae and were explained by distinct habitat characteristics(canopy openness,litter depth,deadwood volume,and tree height).While the diverse tree communities and heterogeneous vegetation structure off ered food and habitat resources for diverse arthropod groups,the allelopathic nature coupled with homogenous stand characteristics of the Tectona grandis stands in the monoculture suppressed the growth of understorey vegetation that could otherwise serve as food and habitat resources for arthropods,which might have led to limited activities and diversity of arthropods in the monoculture plantation stands.The fi ndings thus highlight the need to promote mixed tree plantations in degraded tropical areas,especially when restoring biodiversity is the prime management focus.
文摘Arthropod community structure and diversity were investigated in transgenic insect-resistant hybrid poplar 741 field trial plots, which had five isogenic clones with two genes （Bt. toxin [Cry IAc] and arrowhead proteinase inhibitor [API]） in comparison to control plots. Transgenic poplar clones were investigated according to their insect resistance （high and medium resistant clones）, being systematically probed into varying levels with feeding tests before. Investigations were carded out during three years （2002, 2003 and 2005）. The results indicated that among the basal species, transgenic plants in general had lower amounts of phytophagous insects, and an increased quantity of neutral arthropods such as saprophytic and strolling species. Among the top and intermediate species in transgenic variants, the quantity of predatory natural enemies was increased, while the amount of parasitoid ones was slightly reduced. The arthropod community characteristic indices were analyzed from different aspects in the three variants. It was discovered that, not only the characteristic indices of the whole arthropod community, but also the characteristic indices of the sub-communities （such as natural enemy, pest and neutral arthropods） and the functional groups categorized by their feeding patterns, showed a higher diversity and evenness and a lower dominancy concentration indices in the high-resistant and medium-resistant plots compared with the control. Transgenic poplar 741 showed improved ecological effects both in partial and total aspects. It could be concluded that composition and structure of the arthropod community in plots with transgenic insect-resistant poplar were turned to be more reasonable and itsdiversity and stability was enhanced.
文摘Objective:To determine distribution of arthropods in processed rice products such as rice flour and rice cereal-based infant food.Methods:Random samples of rice flour and rice cereal-based infant food purchased from commercial outlets were examined for the presence of arthropods using a modified Berlese Tullgren Funnel Method.Mites were mounted prior to identification and weevils were directly identified.Results:For non-expired products, infestation was found in 6.7%of rice flour and none was found in rice cereal-based infant food samples.The arthropods found in the flour samples were Cheyletus spp.,Suidasia pontifica(S. pontifica),Tarsonemus spp.,Tyrophagus putrescentiae(T.putrescentiae),Sitophilus granarius(S. granarius) and Sitophilus oryzae(S.oryzae).Others which cannot be identified were Oribatid and Prostigmatid mites.The most common mites in rice flour were Tarsonemus spp.(69.1%),followed by S.pontifica(18.2%).For expired products,only one sample of rice cereal-based infant food was infested and the infestation was by mites of the family Tydeidae.Conclusions:This study demonstrates the presence of 4 allergenic species of S.pontifica,T.putrescentiae,S.granarius and S.oryzae in rice flour.These arthropods can contribute to the incidence of anaphylaxis upon consumption by atopic individuals.There was no infestation of arthropods in rice cereal-based infant food surveyed except for an expired product in a moderate rusty tin container.
文摘Quercus rugosa and Q.laurina are species that presents a wide geographical distribution range in temperate forests of Mexico. Oak canopies contain a considerable portion of arthropod diversity and the arthropods fauna fulfill a wide variety of ecological roles. We examined the effect of oak species and seasonal changes on some community structure parameters (diversity,composition,similarity,biomass,rare species,and density of arthropod fauna) of canopy arthropods. In total,40 oak canopies were fogged during rainy and dry season. A total of 614 identified arthropod morphospecies were recognized belonging to 22 orders associated with tree canopies. A separation of host tree species during both seasons,suggesting a different community structure on host plants species was demonstrated by the principal component analyses (PCA),therefore,differences between oak species results in phenotypes that structure the composition of the arthropod community. Q.laurina registered the highest densities,diversity index and number of rare species in comparison with Q.rugosa. While arthropod biomass showed an inverse pattern. Trees more close to one another (spatial distance) register a more similar canopy arthropod fauna. This study suggests that the trees of Q.laurina could act as a center of biodiversity by the accumulation of arthropod fauna with a considerable number of rare species,which presents wide ecological roles or is involved in critical processes that maintain forest ecosystems.
基金supported by UNAM-DGAPAPAPIIT IN220912 Grant to ZC-S
文摘Arthropod communities and epiphytic plants associated with tree canopies have been widely studied and have revealed a great diversity of organisms; however,the community hosted by parasitic plants,such as dwarf mistletoes,remains poorly known.In the coniferous forests of North America,dwarf mistletoe infection（Arceuthobium spp.） significantly damages the health of the forest,causing large financial losses for the forest industry,but it also positively affects diversity,especially of mammals and birds.This study examined the attributes of the arthropod communities associated with two species of dwarf mistletoe [Arceuthobium globosum Hawksw.＆ Wiens and A.vaginatum（Humb.＆ Bonpl.ex Willd.） J.Presl] and their host Pinus hartwegii Lindl.In 2010,in five sites located in Zoquiapan（Central Mexico）,we collected plant tissue from the three species bimonthly.Arthropods were separated from the plant tissue and identified to the finest level possible.We collected 32,059 individuals,for which51 morphospecies were identified,belonging to 15 taxonomic orders; the most abundant orders for the three plants were Prostigmata,Thysanoptera and Homoptera.The community associated with P.hartwegii had the highest value of diversity（H＇= 1.47; A.globosum,H＇= 0.64; A.vaginatum,H＇= 0.68） and species richness（S = 40; A.globosum,S = 30; A.vaginatum,S = 35）; while abundance was significantly higher for the mistletoes（A.globosum,n = 407 individuals/sample; A.vaginatum,n = 536 individuals/sample; P.hartwegii,n = 134 individuals/sample）.Species richness,abundance and diversity were significantly different for the three studied plants,as well for sampling month and the interaction of these two factors（except for diversity）.The results suggest that the canopy of P.hartwegii is an important element in the ecosystem,providing a mosaic of resources and conditions to the associated fauna.We also propose that mistletoes are key species within the forest canopy,as they greatly influence the establishment of diverse organisms,particularly arthropods.
基金supported by the National Key Research and Development Program of China(2017YFD0501805)the Natural Science Foundation of Shanghai,China(19ZR1469000)+1 种基金the Shanghai Science and Technology Development Funds(17391901600)the Project of International Science and Technology Cooperation,China(2014DFE30140)。
文摘Biting midges of the genus Culicoides(order Diptera,family Ceratopogonidae)are potential biological vectors for the transmission of certain arboviruses among humans,livestock,and wild animals.This study collected a total of 405 Culicoides individuals from seven animal farms located in five counties in the border areas of Yunnan Province,China,and examined the Culicoides species composition and the major arboviruses carried by the Culicoides species.The collected Culicoides were classified into seven species with variable abundances:Culicoides arakawae(5.43%,22/405),Culicoides homotomus(1.23%,5/405),Culicoides obsoletus(19.75%,80/405),Culicoides orientalis(17.28%,70/405),Culicoides oxystoma(29.38%,119/405),Culicoides peregrinus(5.68%,23/405),and Culicoides nipponensis(21.23%,86/405).Among the seven species,C.oxystoma and C.nipponensis were distributed in all the five counties with abundances of 13.33–44.87%and 10.00–46.83%,respectively,suggesting that these were the dominant species of Culicoides widespread on animal farms in the border areas.PCR was used to detect major arboviruses in the collected Culicoides specimens,including bluetongue virus(BTV),Japanese encephalitis virus,Dengue virus,Zika virus,African swine fever virus,and African horse sickness virus.Among the tested viruses,only BTV serotype 1 was tested positive in C.oxystoma specimens collected from a buffalo farm.Culicoides oxystoma was the dominant species on animal farms in the sampled areas,but it has not previously been documented as positive for BTV in China.The current results thus suggest that C.oxystoma could be an important vector for BTV transmission in these border areas,which,however,needs to be confirmed by further comprehensive experiments.Overall,the present study provides the first profile of Culicoides species on animal farms in the China,Vietnam,and Myanmar border areas,establishes the prevalence of arboviruses carried by these Culicoides species,and suggests the vector potential of C.oxystoma species for the transmission of BTV.
文摘Background: Grit is used by birds mainly for grinding hard food items but can also serve a nutritional role as a source of minerals. Ingestion of grit by birds has been documented primarily in species that feed on seeds and invertebrates.Although feeding mainly on nectar and small arthropods, hummingbirds also ingest grit, but why they do so is unclear. We quantified the number of grit particles in the stomachs of six species of hummingbirds during an annual cycle in a seasonal ecosystem of West Mexico.Methods: We compared the number of grit particles in the stomachs of different hummingbird species(Mexican Violetear Colibri thalassinus, Amethyst-throated Mountaingem Lampornis amethystinus, White-eared Hummingbird Basilinna leucotis, Rivoli's Hummingbird Eugenes fulgens, Broad-tailed Hummingbird Selasphorus platycercus, and Rufous Hummingbird S. rufus), and between sex and age categories during the different seasons of a year. To deter-mine if grit was used to grind ingested arthropods, we examined the relationships between the number of grit parti-cles, the biomass of arthropods ingested, and their chitin content.Results: Although species did not differ in the number of grit particles in their stomachs, we found that grit was mostly ingested by female individuals, with only one male of one species(Mexican Violetear) presenting grit in its stomach. We also found that female hummingbirds had grit in their stomachs during the rainy and the cold-dry season(June-February) but not during the warm-dry season(March-May). Our analyses revealed no relationship between the number of grit particles and the amount of ingested arthropods and arthropod chitin content. However,high grit consumption was related to wasp ingestion on Mexican Violetears.Conclusions: Our results indicate that grit is used mainly by female hummingbirds. The seasonal variation in the ingestion of grit by female individuals suggests that it can be used to meet mineral requirements related to breed-ing;however, this topic needs further exploration. Additionally, the use of grit was proportionally higher in juvenile individuals, suggesting it is used for grinding arthropods during a period of fast development.
基金funded by Ente di Gestione delle Aree protette delle Alpi Marittime(Managing Body of protected areas of Maritime Alps)for the research project“Monitoraggio della vegetazione periglaciale dei ghiacciai Clapier e Peirabroc(Alpi Marittime)”,(Monitoring of proglacial vegetation of Clapier and Peirabrocn glaciers(Maritime Alps))within the project ALCOTRA n.1711 CClima TT。
文摘We applied a multi-taxa approach integrating the co-occurrence of plants,ground beetles,spiders and springtails with soil parameters(temperatures and chemical characteristics)in order to describe the primary succession along two glacier forelands in the Maritime Alps(Italy),a hotspot of Mediterranean biodiversity.We compared these successions to those from Central Alps:Maritime glacier forelands markedly differ for their higher values of species richness and species turnover.Contrary to our expectation,Maritime glacier forelands follow a‘replacement change model’,like continental succession of Inner Alps and differently from other peripheral successions.We propose that the temperatures along these Mediterranean glacier forelands are warmer than those along other Alpine glacier forelands,which promote the faster species turnover.Furthermore,we found that early and mid successional stages of the investigated glaciers are richer in cold-adapted and endemic species than the later ones:we confirmed that the‘replacement change’model disadvantages pioneer,cold-adapted species.Given the overall correspondence among coldadapted and endemic species,the most threatened in this climate phase,our results raise new concerns about the extinction risk of these species.We also describe supraglacial habitat of Maritime glaciers demonstrating that supraglacial debris represents an environment decoupled from the regional climate and may have an important role as refugium for coldadapted and hygrophilous plant and animal species,whose survival can be threatened by climate change and by a rapid ecological succession in the adjacent forelands.
