DNA sequence diversities of soil microbial communities in rhizosphere and non-rhizosphere of 1 - 6 years Panax ginseng were evaluated by random amplified polymorphic DNA (RAPD). Total genomic DNA of soil samples were ...DNA sequence diversities of soil microbial communities in rhizosphere and non-rhizosphere of 1 - 6 years Panax ginseng were evaluated by random amplified polymorphic DNA (RAPD). Total genomic DNA of soil samples were amplified by twenty-four out of two hundred random primers. The products were separated in agarose gel, and 359 and 181 reliable fragments were generated, of which, 324 and 123 were polymorphic. The gene diversity index, Shannon’s information index, and similarity coefficient were calculated, and results showed that, diversity of soil microbial community at DNA level was present. Furthermore, with the increasing of P. ginseng growing at one site, deference on soil microbial community DNA sequence between rhizosphere and non-rhizosphere tend to be more and more significant. In addition, RAPD technique was proved to be an effective tool to assess the diversity of soil microbial communities. From results we deduced that, the ecological function that performed by soil microbes may changed following the change of microbial community in rhizospheric and non-rhizospheric soils, and finally broke the balance of soil nutrition and energy cycle, soil spatial structure, microbial ecology etc.展开更多
The Paramesotriton caudopunctatus species group is mainly distributed in the karst mountain ecosystems of Guizhou, China. Although some species have been included in previous phylogenetic studies, the evolutionary rel...The Paramesotriton caudopunctatus species group is mainly distributed in the karst mountain ecosystems of Guizhou, China. Although some species have been included in previous phylogenetic studies, the evolutionary relationships and divergence-time of members of this species group as a whole remain unexplored. In this study, we report the sequencing of one protein coding mitochondrial gene fragment(ND2) and one nuclear gene(POMC), and use a combination of phylogenetic analyses and coalescent simulations to explore the cryptic diversity and evolutionary history of the P. caudopunctatus species group. Phylogenetic relationships revealed that the P. caudopunctatus species group is composed of two major groups, i. e., East Clade and Western-South Clade. The divergence-time and ancestral area estimation suggested that the P. caudopunctatus species group likely originated in the Doupeng Mountains in Guizhou, China at 12.34 Ma(95% HPD: 8.30–14.73), and intraspecific divergence began at about 2.17 Ma(95% HPD: 1.39–2.97). This timing coincides with the orogenesis of the Miaoling Mountains during the Late Miocene to early Pleistocene. The delimitation of species in the P. caudopunctatus species group supports the existence of the currently identified species, and consensus was confirmed across methods for the existence of least to two cryptic species within what has been traditionally considered to be P. caudopunctatus species group. This study is of significance for understanding the species formation, dispersal, and diversity of the tailed amphibians in the karst mountains ecosystem of Guizhou and the role of the Miaoling Mountains as a geographical barrier to species dispersal.展开更多
Vegetation restoration can alter carbon(C),nitrogen(N),and phosphorus(P)cycles in coastal wetlands affecting C:N:P stoichiometry.However,the effects of restoration age on soil C:N:P stoichiometry are unclear.In this s...Vegetation restoration can alter carbon(C),nitrogen(N),and phosphorus(P)cycles in coastal wetlands affecting C:N:P stoichiometry.However,the effects of restoration age on soil C:N:P stoichiometry are unclear.In this study,we examined the re-sponses of soil C,N,and P contents and their stoichiometric ratios to vegetation restoration age,focusing on below-ground processes and their relationships to aboveground vegetation community characteristics.We conducted an analysis of temporal gradients based on the'space for time'method to synthesize the effects of restoration age on soil C:N:P stoichiometry in the Yellow River Delta wetland of China.The findings suggest that the combined effects of restoration age and soil depth create complex patterns of shifting soil C:N:P stoichiometry.Specifically,restoration age significantly increased all topsoil C:N:P stoichiometries,except for soil total phosphorus(TP)and the C:N ratio,and slightly affected subsoil C:N:P stoichiometry.The effects of restoration age on the soil C:N ratio was well constrained owing to the coupled relationship between soil organic carbon(SOC)and total nitrogen(TN)contents,while soil TP con-tent was closely related to changes in plant species diversity.Importantly,we found that the topsoil C:N:P stoichiometry was signific-antly affected by plant species diversity,whereas the subsoil C:N:P stoichiometry was more easily regulated by pH and electric con-ductivity(EC).Overall,this study shows that vegetation restoration age elevated SOC and N contents and alleviated N limitation,which is useful for further assessing soil C:N:P stoichiometry in coastal restoration wetlands.展开更多
Tropical alpine ecosystems exhibit outstanding plant diversity and endemism while being particularly sensitive to the impacts of climate change.Although understanding spatiotemporal changes in plant species compositio...Tropical alpine ecosystems exhibit outstanding plant diversity and endemism while being particularly sensitive to the impacts of climate change.Although understanding spatiotemporal changes in plant species composition,richness and community structure along tropical alpine altitudinal gradients is of primary importance,both the functional and historical/biogeographic dimensions of vegetation diversity remain largely unexplored.We used Generalized Linear Models and multivariate analyses to assess changes in species,growth forms,and biogeographic groups richness and abundance,in response to habitat variables along an elevation gradient in seven summits(3800 to 4600 m asl)in the Venezuelan Andes,studied using the standardized approach of the GLORIA-Andes monitoring network.The habitat variables assessed were soil temperature(-10 cm),soil organic matter,slope inclination,and substrate cover.We found 113 species,representing72 genera,32 families,13 growth forms,and seven biogeographic origins,that included 25%of endemic elements.We observed richer vegetation,both in terms of species and growth forms,in summits with higher soil temperatures and higher SOM content,as well as higher biogeographic origin richness with increasing soil temperatures.The presence of holarctic elements increased toward higher elevations,while the occurrence of austral antarctic elements increased toward lower elevations.Our results indicate that biogeographic and functional approaches to vegetation diversity capture well the effect of abiotic filtering on community structuring in these tropical alpine environments.These findings constitute an important baseline for monitoring vegetation dynamics linked to climate change in the Venezuelan Andes by highlighting the functional and historical perspective on vegetation analyses,in contrast with more traditional approaches,based only on taxonomic species diversity.展开更多
Livestock ranching is one of the main productive activities in arid regions of the world.Grazing produces changes in animal as well as plant communities(e.g.richness,abundance and species dominance relationships).Ants...Livestock ranching is one of the main productive activities in arid regions of the world.Grazing produces changes in animal as well as plant communities(e.g.richness,abundance and species dominance relationships).Ants are good biological indicators due to the environmental fidelity of some of their community parameters.We described the functional structure of the ant community in the central Monte of Mendoza,Argentina,and examined the effect of grazing using richness,diversity and the functional group scheme.We used pitfall traps to sample ants at a reserve with 30-year cattle exclusion and at an adjacent ranch.Eleven of the 27 recorded species showed significant differences in their abundance and two species were absent at the ranch.While richness and diversity did not reflect these differences,functional groups did.Hot Climate Specialists were more abundant at the ranch while Cryptic Species and Generalized Myrmicinae increased at the reserve.This study supports the utility of the functional group scheme to study the effects of grazing disturbance in ant communities of arid regions.展开更多
This study was conducted in the Korhogo region in an age gradient of mango orchards. The goal was to assess diversity and determine the influence of the environment on the composition of these organisms. Sampling was ...This study was conducted in the Korhogo region in an age gradient of mango orchards. The goal was to assess diversity and determine the influence of the environment on the composition of these organisms. Sampling was done using pitfall traps, threshing and manual collection. A total of 82 ant species were sampled on all plots. The cultivated plots are richer in ant species than the natural environment. Of the three (3) sampling methods, the Manual Collection proved to be more efficient (eff = 79.52%), followed by threshing (eff = 75.15%) and finally the least effective trap pit (eff = 73.39%). The number of individuals of the species varies according to the environment. The highest value was obtained in the young plot (485 individuals), followed by the intermediate plot (478 individuals), then the older plot (426 individuals) and finally the control plot (320 individuals). The species Camponotus acvapimensis was harvested mainly with 159 individuals. On the other hand, the species Lepisiota sp.1;Camponotus rufigenis, Camponotus sericeus and Oecophylla longinoda were specifically harvested in the control, young, intermediate and aged plots, respectively.展开更多
This paper describes a routing algorithm for risk scanning agents using ant colony algorithm in P2P(peerto peer) network. Every peer in the P2P network is capable of updating its routing table in a real-time way, wh...This paper describes a routing algorithm for risk scanning agents using ant colony algorithm in P2P(peerto peer) network. Every peer in the P2P network is capable of updating its routing table in a real-time way, which enables agents to dynamically and automatically select, according to current traffic condition of the network, the global optimal traversal path. An adjusting mechanism is given to adjust the routing table when peers join or leave. By means of exchanging pheromone intensity of part of paths, the algorithm provides agents with more choices as to which one to move and avoids prematurely reaching local optimal path. And parameters of the algorithm are determined by lots of simulation testing. And we also compare with other routing algorithms in unstructured P2P network in the end.展开更多
The ants are one of the mega diverse insets found in all terrestrial environments, and occur in great diversity, richness and abundance, acting at all trophic levels. The present study was conducted to verify the know...The ants are one of the mega diverse insets found in all terrestrial environments, and occur in great diversity, richness and abundance, acting at all trophic levels. The present study was conducted to verify the knowledge of ant fauna at Caxiuanã National forest. All available ant literature and some collection in Caxiuanã were compiled and analyzed in EXCEL program. Caxiuanã is one Brazilian Amazonia forest that has good biological conservation. A total of 197 species belonging to 52 genera of the nine subfamilies are present in Caxiuanã. Many studies need to be done in this place to understand the ant community pattern to give base for other studies and proposal for use, management and conservation of this interesting Amazonia place.展开更多
The ants are one of the mega diverse insets found in all terrestrial environments, and occur in great diversity, richness and abundance, acting at all trophic levels. The present study was conducted to verify the know...The ants are one of the mega diverse insets found in all terrestrial environments, and occur in great diversity, richness and abundance, acting at all trophic levels. The present study was conducted to verify the knowledge of ant fauna at Caxiuanã National forest. All available ant literature and some collection in Caxiuanã were compiled and analyzed in EXCEL program. Caxiuanã is one Brazilian Amazonia forest that has good biological conservation. A total of 197 species belonging to 52 genera of the nine subfamilies are present in Caxiuanã. Many studies need to be done in this place to understand the ant community pattern to give base for other studies and proposal for use, management and conservation of this interesting Amazonia place.展开更多
Distribution characteristics of soil phosphorus availability and its correlations with plant species diversity in the forest ecosystem of Mt.Jinyun are studied in this paper.The results are as follows:①Available P of...Distribution characteristics of soil phosphorus availability and its correlations with plant species diversity in the forest ecosystem of Mt.Jinyun are studied in this paper.The results are as follows:①Available P of soil profile in different communities has an evident gradient,i.e.,A(humus layer)>B(deposition layer)>C(parent material layer).②Except for shrub-grassland,soil available P content orderly increases along the successional directions,i.e.,Pinus massoniana forest<P.massonia-Symplocos setchuensis mixed forest<evergreen broadleaved forest.③Different degree’s of correlations exist between soil available P and plant species diversity.The correlation between tree diversity and available P content of A and B layers is very significant.展开更多
文摘DNA sequence diversities of soil microbial communities in rhizosphere and non-rhizosphere of 1 - 6 years Panax ginseng were evaluated by random amplified polymorphic DNA (RAPD). Total genomic DNA of soil samples were amplified by twenty-four out of two hundred random primers. The products were separated in agarose gel, and 359 and 181 reliable fragments were generated, of which, 324 and 123 were polymorphic. The gene diversity index, Shannon’s information index, and similarity coefficient were calculated, and results showed that, diversity of soil microbial community at DNA level was present. Furthermore, with the increasing of P. ginseng growing at one site, deference on soil microbial community DNA sequence between rhizosphere and non-rhizosphere tend to be more and more significant. In addition, RAPD technique was proved to be an effective tool to assess the diversity of soil microbial communities. From results we deduced that, the ecological function that performed by soil microbes may changed following the change of microbial community in rhizospheric and non-rhizospheric soils, and finally broke the balance of soil nutrition and energy cycle, soil spatial structure, microbial ecology etc.
基金supported by the programs of the Strategic Priority Research Program B of the Chinese Academy of Sciences (CAS) (No. XDB31000000)the National Natural Science Foundation of China (Grant No. 31460091)+2 种基金the Na tional Animal Collection Resource Center, China (Grant No. 2005DKA21402)the Application of Amphibian Natural Antioxidant Peptides as Cosmetic Raw Material Antioxidants (QKZYD [2020]4002)the National Top Discipline Construction Project of Guizhou Province,Geography in Guizhou Normal University (No. 85 2017 Qianjiao Keyan Fa)。
文摘The Paramesotriton caudopunctatus species group is mainly distributed in the karst mountain ecosystems of Guizhou, China. Although some species have been included in previous phylogenetic studies, the evolutionary relationships and divergence-time of members of this species group as a whole remain unexplored. In this study, we report the sequencing of one protein coding mitochondrial gene fragment(ND2) and one nuclear gene(POMC), and use a combination of phylogenetic analyses and coalescent simulations to explore the cryptic diversity and evolutionary history of the P. caudopunctatus species group. Phylogenetic relationships revealed that the P. caudopunctatus species group is composed of two major groups, i. e., East Clade and Western-South Clade. The divergence-time and ancestral area estimation suggested that the P. caudopunctatus species group likely originated in the Doupeng Mountains in Guizhou, China at 12.34 Ma(95% HPD: 8.30–14.73), and intraspecific divergence began at about 2.17 Ma(95% HPD: 1.39–2.97). This timing coincides with the orogenesis of the Miaoling Mountains during the Late Miocene to early Pleistocene. The delimitation of species in the P. caudopunctatus species group supports the existence of the currently identified species, and consensus was confirmed across methods for the existence of least to two cryptic species within what has been traditionally considered to be P. caudopunctatus species group. This study is of significance for understanding the species formation, dispersal, and diversity of the tailed amphibians in the karst mountains ecosystem of Guizhou and the role of the Miaoling Mountains as a geographical barrier to species dispersal.
基金Under the auspices of Natural Science Foundation of China(No.U2106209,42071126)Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA23050202)International Science Partnership Program of the Chinese Academy of Sciences(No.121311KYSB20190029)。
文摘Vegetation restoration can alter carbon(C),nitrogen(N),and phosphorus(P)cycles in coastal wetlands affecting C:N:P stoichiometry.However,the effects of restoration age on soil C:N:P stoichiometry are unclear.In this study,we examined the re-sponses of soil C,N,and P contents and their stoichiometric ratios to vegetation restoration age,focusing on below-ground processes and their relationships to aboveground vegetation community characteristics.We conducted an analysis of temporal gradients based on the'space for time'method to synthesize the effects of restoration age on soil C:N:P stoichiometry in the Yellow River Delta wetland of China.The findings suggest that the combined effects of restoration age and soil depth create complex patterns of shifting soil C:N:P stoichiometry.Specifically,restoration age significantly increased all topsoil C:N:P stoichiometries,except for soil total phosphorus(TP)and the C:N ratio,and slightly affected subsoil C:N:P stoichiometry.The effects of restoration age on the soil C:N ratio was well constrained owing to the coupled relationship between soil organic carbon(SOC)and total nitrogen(TN)contents,while soil TP con-tent was closely related to changes in plant species diversity.Importantly,we found that the topsoil C:N:P stoichiometry was signific-antly affected by plant species diversity,whereas the subsoil C:N:P stoichiometry was more easily regulated by pH and electric con-ductivity(EC).Overall,this study shows that vegetation restoration age elevated SOC and N contents and alleviated N limitation,which is useful for further assessing soil C:N:P stoichiometry in coastal restoration wetlands.
基金the financial support to the GLORIA-Andes network in Venezuela of CONDESAN and the Swiss Development Agency(SDC)The present synthesis analysis was financed by the Adaptation at Altitude Program(CONDESAN-SDC)。
文摘Tropical alpine ecosystems exhibit outstanding plant diversity and endemism while being particularly sensitive to the impacts of climate change.Although understanding spatiotemporal changes in plant species composition,richness and community structure along tropical alpine altitudinal gradients is of primary importance,both the functional and historical/biogeographic dimensions of vegetation diversity remain largely unexplored.We used Generalized Linear Models and multivariate analyses to assess changes in species,growth forms,and biogeographic groups richness and abundance,in response to habitat variables along an elevation gradient in seven summits(3800 to 4600 m asl)in the Venezuelan Andes,studied using the standardized approach of the GLORIA-Andes monitoring network.The habitat variables assessed were soil temperature(-10 cm),soil organic matter,slope inclination,and substrate cover.We found 113 species,representing72 genera,32 families,13 growth forms,and seven biogeographic origins,that included 25%of endemic elements.We observed richer vegetation,both in terms of species and growth forms,in summits with higher soil temperatures and higher SOM content,as well as higher biogeographic origin richness with increasing soil temperatures.The presence of holarctic elements increased toward higher elevations,while the occurrence of austral antarctic elements increased toward lower elevations.Our results indicate that biogeographic and functional approaches to vegetation diversity capture well the effect of abiotic filtering on community structuring in these tropical alpine environments.These findings constitute an important baseline for monitoring vegetation dynamics linked to climate change in the Venezuelan Andes by highlighting the functional and historical perspective on vegetation analyses,in contrast with more traditional approaches,based only on taxonomic species diversity.
基金partially funded by a grant from the National Council of Research (Argentina) Number 4678 for the project"Insect Biodiversity of the Monte"
文摘Livestock ranching is one of the main productive activities in arid regions of the world.Grazing produces changes in animal as well as plant communities(e.g.richness,abundance and species dominance relationships).Ants are good biological indicators due to the environmental fidelity of some of their community parameters.We described the functional structure of the ant community in the central Monte of Mendoza,Argentina,and examined the effect of grazing using richness,diversity and the functional group scheme.We used pitfall traps to sample ants at a reserve with 30-year cattle exclusion and at an adjacent ranch.Eleven of the 27 recorded species showed significant differences in their abundance and two species were absent at the ranch.While richness and diversity did not reflect these differences,functional groups did.Hot Climate Specialists were more abundant at the ranch while Cryptic Species and Generalized Myrmicinae increased at the reserve.This study supports the utility of the functional group scheme to study the effects of grazing disturbance in ant communities of arid regions.
文摘This study was conducted in the Korhogo region in an age gradient of mango orchards. The goal was to assess diversity and determine the influence of the environment on the composition of these organisms. Sampling was done using pitfall traps, threshing and manual collection. A total of 82 ant species were sampled on all plots. The cultivated plots are richer in ant species than the natural environment. Of the three (3) sampling methods, the Manual Collection proved to be more efficient (eff = 79.52%), followed by threshing (eff = 75.15%) and finally the least effective trap pit (eff = 73.39%). The number of individuals of the species varies according to the environment. The highest value was obtained in the young plot (485 individuals), followed by the intermediate plot (478 individuals), then the older plot (426 individuals) and finally the control plot (320 individuals). The species Camponotus acvapimensis was harvested mainly with 159 individuals. On the other hand, the species Lepisiota sp.1;Camponotus rufigenis, Camponotus sericeus and Oecophylla longinoda were specifically harvested in the control, young, intermediate and aged plots, respectively.
基金Supported by the National Natural Science Foun-dation of China (60403027) Natural Science Foundation of HubeiProvince (2005ABA258) the Opening Foundation of State KeyLaboratory of Software Engineering (SKLSE05-07)
文摘This paper describes a routing algorithm for risk scanning agents using ant colony algorithm in P2P(peerto peer) network. Every peer in the P2P network is capable of updating its routing table in a real-time way, which enables agents to dynamically and automatically select, according to current traffic condition of the network, the global optimal traversal path. An adjusting mechanism is given to adjust the routing table when peers join or leave. By means of exchanging pheromone intensity of part of paths, the algorithm provides agents with more choices as to which one to move and avoids prematurely reaching local optimal path. And parameters of the algorithm are determined by lots of simulation testing. And we also compare with other routing algorithms in unstructured P2P network in the end.
文摘The ants are one of the mega diverse insets found in all terrestrial environments, and occur in great diversity, richness and abundance, acting at all trophic levels. The present study was conducted to verify the knowledge of ant fauna at Caxiuanã National forest. All available ant literature and some collection in Caxiuanã were compiled and analyzed in EXCEL program. Caxiuanã is one Brazilian Amazonia forest that has good biological conservation. A total of 197 species belonging to 52 genera of the nine subfamilies are present in Caxiuanã. Many studies need to be done in this place to understand the ant community pattern to give base for other studies and proposal for use, management and conservation of this interesting Amazonia place.
文摘The ants are one of the mega diverse insets found in all terrestrial environments, and occur in great diversity, richness and abundance, acting at all trophic levels. The present study was conducted to verify the knowledge of ant fauna at Caxiuanã National forest. All available ant literature and some collection in Caxiuanã were compiled and analyzed in EXCEL program. Caxiuanã is one Brazilian Amazonia forest that has good biological conservation. A total of 197 species belonging to 52 genera of the nine subfamilies are present in Caxiuanã. Many studies need to be done in this place to understand the ant community pattern to give base for other studies and proposal for use, management and conservation of this interesting Amazonia place.
文摘Distribution characteristics of soil phosphorus availability and its correlations with plant species diversity in the forest ecosystem of Mt.Jinyun are studied in this paper.The results are as follows:①Available P of soil profile in different communities has an evident gradient,i.e.,A(humus layer)>B(deposition layer)>C(parent material layer).②Except for shrub-grassland,soil available P content orderly increases along the successional directions,i.e.,Pinus massoniana forest<P.massonia-Symplocos setchuensis mixed forest<evergreen broadleaved forest.③Different degree’s of correlations exist between soil available P and plant species diversity.The correlation between tree diversity and available P content of A and B layers is very significant.