Seasonal shifts play an important role in soil microbial community composition. This study examined the hypothesis that soil microbial community structure would vary with seasonal shifts in the Wuyi Mountains in South...Seasonal shifts play an important role in soil microbial community composition. This study examined the hypothesis that soil microbial community structure would vary with seasonal shifts in the Wuyi Mountains in Southeast China, and that two representative tree species （Castanopisi carlesii and Cunninghamia lanceolata） may have different soil microbial community composition. Phospholipids fatty acid analysis （PLFA） of seasonal shifts and was used to assess the effect vegetation types on soil microbial community structure. A total of 22 different PLFAs were identified from all the soil samples. The bacterial PLFAs accounted for 62.37% of the total PLFAs, followed by fungi （28.94%）, and the minimum was actinomycetes （6.41%）. Overall, the level of PLFAs in C. carlesii soil was greater than those in C. lanceolata soil, and significant differences were observed in some seasons. The amounts of total, bacteria, actinomycic and fungal PLFAs significantly changed with the seasons and followed a sequence order （summer 〉 autumn 〉 spring 〉 winter）. The bacteria/fungi PLFAs and G （＋）/G （-） PLFAs of two vegetation types also changed with the seasons and the ratios in summer and autumn were higher than those in spring and winter. The correlation analysis of microbial PLFAs and soil physicochemical properties showed that the total, bacteria, fungal, actinomycic, G （＋） and G （-） PLFAs were significantly positive correlation with TOC, TN, TP, TK and moisture content. We concluded that the seasonal shifts and vegetation types affect soil microbial community composition by changing the soil physicochemical properties.展开更多
Diet composition and its ecological drivers are rarely investigated in coexisting closely related species.We used a molecular approach to characterize the seasonal variation in diet composition in four spiny lizard sp...Diet composition and its ecological drivers are rarely investigated in coexisting closely related species.We used a molecular approach to characterize the seasonal variation in diet composition in four spiny lizard species inhabiting a mountainous ecosystem.DNA metabarcoding revealed that the lizards Sceloporus aeneus,S.bicanthalis,S.grammicus,and S.spinosus mostly consumed arthropods of the orders Hemiptera,Araneae,Hymenoptera,and Coleoptera.The terrestrial lizards S.aeneus and S.bicanthalis mostly predated ants and spiders,whereas the arboreal–saxicolous S.grammicus and saxicolous S.spinosus largely consumed grasshoppers and leafhoppers.The taxonomic and phylogenetic diversity of the prey was higher during the dry season than the rainy season,likely because reduced prey availability in the dry season forced lizards to diversify their diets to meet their nutritional demands.Dietary and phylogenetic composition varied seasonally depending on the species,but only dietary composition varied with altitude.Seasonal dietary turnover was greater in S.spinosus than in S.bicanthalis,suggesting site-specific seasonal variability in prey availability;no other differences among species were observed.S.bicanthalis,which lives at the highest altitude in our study site,displayed interseasonal variation in diet breadth.Dietary differences were correlated with the species’feeding strategies and elevational distribution,which likely contributed to the coexistence of these lizard species in the studied geographic area and beyond.展开更多
Soil microbial communities and enzyme activities play key roles in soil ecosystems.Both are sensitive to changes in environmental factors,including seasonal temperature,precipitation variations and soil properties.To ...Soil microbial communities and enzyme activities play key roles in soil ecosystems.Both are sensitive to changes in environmental factors,including seasonal temperature,precipitation variations and soil properties.To understand the interactive mechanisms of seasonal changes that affect soil microbial communities and enzyme activities in a subtropical masson pine(Pinus massoniana)forest,we investigated the soil microbial community structure and enzyme activities to identify the effect of seasonal changes on the soil microbial community for two years in Jinyun Mountain National Nature Reserve,Chongqing,China.The soil microbial community structure was investigated using phospholipid fatty acids(PLFAs).The results indicated that a total of 36 different PLFAs were identified,and 16:0 was found in the highest proportions in the four seasons,moreover,the total PLFAs abundance were highest in spring and lowest in winter.Bacteria and actinomycetes were the dominant types in the study area.Seasonal changes also had a significant(P<0.05)influence on the soil enzyme activity.The maximum and minimum values of the invertase and catalase activities were observed in autumn and winter,respectively.However,the maximum and minimum values of the urease and phosphatase acid enzymatic activities were found in spring and winter,respectively.Canonical correspondence analysis(CCA)analysis revealed that the seasonal shifts in soil community composition and enzyme activities were relatively more sensitive to soil moisture and temperature,but the microbial community structure and enzyme activity were not correlated with soil pH in the study region.This study highlights how the seasonal variations affect the microbial community and function(enzyme activity)to better understand and predict microbial responses to future climate regimes in subtropical area.展开更多
Compositional changes of the bacterioplankton assemblages in four high altitude middle Atlas lakes were monitored over a complete seasonal cycle using combinations of culture-dependent and molecular approaches. Viable...Compositional changes of the bacterioplankton assemblages in four high altitude middle Atlas lakes were monitored over a complete seasonal cycle using combinations of culture-dependent and molecular approaches. Viable bacterial numbers varied between seasons, with the lowest numbers recorded in the winter and the highest in the summer in all four lakes. Also, bacterial occurrences were found to be strongly correlated with water temperature in all the four sites, i.e., Lake Aoua (0.88), Ifreh (0.59), Hechlef (0.77) and Affourgagh (0.79) during the study period. Standard microbiological characterization of bacteria isolates from the lakes revealed majority (68%) to be Gram positive. Seasonal variations in the microbial assemblages among the lakes were also validated by restriction fragment length polymorphism (RFLP). Shifts in microbial assemblages, especially of the fecal indicator bacteria appeared to also be influenced by differences in the morphometric and watershed characteristics among the lakes. This study further reveals the need to employ combinations of methodological approaches, including taxonomic, physiological and molecular methods to adequately delineate and fully understand the ecology of microbial assemblages in extreme environments.展开更多
基金supported by the National Natural Science Foundation of China (Grant No.31500443)Fujian Province Department of Education Foundation (Grant No.JA15178)
文摘Seasonal shifts play an important role in soil microbial community composition. This study examined the hypothesis that soil microbial community structure would vary with seasonal shifts in the Wuyi Mountains in Southeast China, and that two representative tree species （Castanopisi carlesii and Cunninghamia lanceolata） may have different soil microbial community composition. Phospholipids fatty acid analysis （PLFA） of seasonal shifts and was used to assess the effect vegetation types on soil microbial community structure. A total of 22 different PLFAs were identified from all the soil samples. The bacterial PLFAs accounted for 62.37% of the total PLFAs, followed by fungi （28.94%）, and the minimum was actinomycetes （6.41%）. Overall, the level of PLFAs in C. carlesii soil was greater than those in C. lanceolata soil, and significant differences were observed in some seasons. The amounts of total, bacteria, actinomycic and fungal PLFAs significantly changed with the seasons and followed a sequence order （summer 〉 autumn 〉 spring 〉 winter）. The bacteria/fungi PLFAs and G （＋）/G （-） PLFAs of two vegetation types also changed with the seasons and the ratios in summer and autumn were higher than those in spring and winter. The correlation analysis of microbial PLFAs and soil physicochemical properties showed that the total, bacteria, fungal, actinomycic, G （＋） and G （-） PLFAs were significantly positive correlation with TOC, TN, TP, TK and moisture content. We concluded that the seasonal shifts and vegetation types affect soil microbial community composition by changing the soil physicochemical properties.
基金Funding was provided by the Consejo Nacional de Ciencia y Tecnología(CONACyT)through the Infraestructura project(205945)the Ciencia de Frontera project(137748)+2 种基金the Cátedras CONACyT project(883)by the Universidad Nacional Autónoma de México(UNAM).M.H.received PhD scholarship(967648)S.H.-P.,postdoctoral grant(929602)from CONACyT.
文摘Diet composition and its ecological drivers are rarely investigated in coexisting closely related species.We used a molecular approach to characterize the seasonal variation in diet composition in four spiny lizard species inhabiting a mountainous ecosystem.DNA metabarcoding revealed that the lizards Sceloporus aeneus,S.bicanthalis,S.grammicus,and S.spinosus mostly consumed arthropods of the orders Hemiptera,Araneae,Hymenoptera,and Coleoptera.The terrestrial lizards S.aeneus and S.bicanthalis mostly predated ants and spiders,whereas the arboreal–saxicolous S.grammicus and saxicolous S.spinosus largely consumed grasshoppers and leafhoppers.The taxonomic and phylogenetic diversity of the prey was higher during the dry season than the rainy season,likely because reduced prey availability in the dry season forced lizards to diversify their diets to meet their nutritional demands.Dietary and phylogenetic composition varied seasonally depending on the species,but only dietary composition varied with altitude.Seasonal dietary turnover was greater in S.spinosus than in S.bicanthalis,suggesting site-specific seasonal variability in prey availability;no other differences among species were observed.S.bicanthalis,which lives at the highest altitude in our study site,displayed interseasonal variation in diet breadth.Dietary differences were correlated with the species’feeding strategies and elevational distribution,which likely contributed to the coexistence of these lizard species in the studied geographic area and beyond.
基金supported by the National Key Research and Developmental Program of China(2016YFC0502303)the Special Fund for Department of Water Resources of Guizhou Province,China(KT201617)。
文摘Soil microbial communities and enzyme activities play key roles in soil ecosystems.Both are sensitive to changes in environmental factors,including seasonal temperature,precipitation variations and soil properties.To understand the interactive mechanisms of seasonal changes that affect soil microbial communities and enzyme activities in a subtropical masson pine(Pinus massoniana)forest,we investigated the soil microbial community structure and enzyme activities to identify the effect of seasonal changes on the soil microbial community for two years in Jinyun Mountain National Nature Reserve,Chongqing,China.The soil microbial community structure was investigated using phospholipid fatty acids(PLFAs).The results indicated that a total of 36 different PLFAs were identified,and 16:0 was found in the highest proportions in the four seasons,moreover,the total PLFAs abundance were highest in spring and lowest in winter.Bacteria and actinomycetes were the dominant types in the study area.Seasonal changes also had a significant(P<0.05)influence on the soil enzyme activity.The maximum and minimum values of the invertase and catalase activities were observed in autumn and winter,respectively.However,the maximum and minimum values of the urease and phosphatase acid enzymatic activities were found in spring and winter,respectively.Canonical correspondence analysis(CCA)analysis revealed that the seasonal shifts in soil community composition and enzyme activities were relatively more sensitive to soil moisture and temperature,but the microbial community structure and enzyme activity were not correlated with soil pH in the study region.This study highlights how the seasonal variations affect the microbial community and function(enzyme activity)to better understand and predict microbial responses to future climate regimes in subtropical area.
文摘Compositional changes of the bacterioplankton assemblages in four high altitude middle Atlas lakes were monitored over a complete seasonal cycle using combinations of culture-dependent and molecular approaches. Viable bacterial numbers varied between seasons, with the lowest numbers recorded in the winter and the highest in the summer in all four lakes. Also, bacterial occurrences were found to be strongly correlated with water temperature in all the four sites, i.e., Lake Aoua (0.88), Ifreh (0.59), Hechlef (0.77) and Affourgagh (0.79) during the study period. Standard microbiological characterization of bacteria isolates from the lakes revealed majority (68%) to be Gram positive. Seasonal variations in the microbial assemblages among the lakes were also validated by restriction fragment length polymorphism (RFLP). Shifts in microbial assemblages, especially of the fecal indicator bacteria appeared to also be influenced by differences in the morphometric and watershed characteristics among the lakes. This study further reveals the need to employ combinations of methodological approaches, including taxonomic, physiological and molecular methods to adequately delineate and fully understand the ecology of microbial assemblages in extreme environments.
