Arbuscular mycorrhizal fungi(AMF)play a vital role in plant productivity and ecosystem functions.However,their responses to abiotic factors(i.e.,climate,physiography,and soil properties)are unknown,especially across c...Arbuscular mycorrhizal fungi(AMF)play a vital role in plant productivity and ecosystem functions.However,their responses to abiotic factors(i.e.,climate,physiography,and soil properties)are unknown,especially across climatic gradients and slope aspects in arid and semi-arid ecosys-tems.In this study,using 60 composite soil samples,direct and indirect effects of climate factors and slope aspects on AMF diversity,composition and spore density were studied.The findings indicate that climate has a more direct influ-ence on soil properties(P<0.001)in comparison to slope aspect(P=0.449).In contrast,climate significantly affected AMF diversity and composition,with the highest diversity in dryer areas.Soil pH had the highest correlation with different facets of AMF diversity.Structural equation modeling(SEM)indicated that only a small part of the variation in AMF diversity and spore density could be explained by climate characteristics,slope aspect and soil properties.Based on SEM results,climate was the most important determinant of AMF diversity and spore density;slope aspect had a less critical role.The outputs suggest that variations in AMF diversity are derived by the direct effects of climate and the indirect effect of soil chemical properties.In addition,with increasing dryness,sporulation and AMF diversity increased.展开更多
Arbuscular mycorrhizal fungi(AMF)form a near-ubiquitous mutualistic association with roots to help plants withstand harsh environments,and play a key role in the establishment of coastal beach plant communities.Yet li...Arbuscular mycorrhizal fungi(AMF)form a near-ubiquitous mutualistic association with roots to help plants withstand harsh environments,and play a key role in the establishment of coastal beach plant communities.Yet little is known about the structure and composition of AMF communities on coastal beaches of eastern China.In this study,we investigated the occurrence,community composition and diversity of AMF associated with common wild plants on a coastal beach of North Jiangsu,China.Almost all of the local wild species were colonized by AMF except for Chenopodium album L.Thirty-seven AMF species were isolated from the rhizosphere belonging to 12 genera in seven families.Glomus was the dominant genus and Funneliformis mosseae the dominant species.The colonization,spore composition and diversity of AMF were strongly related to edaphic factors.Sodium(Na^(+))ions in the soil significantly and negatively affected the colonization rate by AMF and both soil Na^(+)levels and pH had a significant negative effect on AMF spore density and evenness.However,there was a significant positive correlation between species richness and total organic carbon.The results provide insights into soil factors affecting native AMF communities in coastal beach habitats which could benefit vegetation recovery and soil reclamation efforts.展开更多
In conversion of the integrated slant column amount of atmospheric ozone(O_3)measured by the ground-based spectrometer technique during twilight to the vertical quantity,the air-mass factor(AMF)is an important paramet...In conversion of the integrated slant column amount of atmospheric ozone(O_3)measured by the ground-based spectrometer technique during twilight to the vertical quantity,the air-mass factor(AMF)is an important parameter.In this work,calculations of AMF for ozone were performed for different atmospheres.It is shown that the O_3 AMF has seasonal variations with the minimum at the beginning of spring and the maximum in summer due to the seasonal change in the vertical distributions of O_3.A parameterization relation is obtained between O_3 AMF and optical thickness of stratospheric volcanic aerosols based on the Monte-Carlo radiative transfer simulations.展开更多
Olive(Olea europaea L.)is one of the most important and widely cultivated fruit trees,with high economic,ecological,cultural and scientific value.China began introducing and cultivating olive in the 1960s,and Yunnan P...Olive(Olea europaea L.)is one of the most important and widely cultivated fruit trees,with high economic,ecological,cultural and scientific value.China began introducing and cultivating olive in the 1960s,and Yunnan Province is one of the main growing areas.Improving the cultivation and productivity of this tree crop species is an important challenge.Olive is a typical mycotrophic species and the potential of arbuscular mycorrhizal fungi(AMF)for this plant is well recognized;nevertheless,studies of olive AMF in China are still very limited.Roots and rhizosphere soils of olive were sampled from five representative growing sites in the Yunnan Province of China to investigate the AMF colonization status in the root systems,the AMF community in the olive orchards and the edaphic factors influencing the arbuscular mycorrhizal(AM)parameters.Root samples of olive trees from different growing sites generally showed AMF colonization,suggesting that autochthonous AMF manifest a high efficiency in colonizing the roots of olive plants.The spore density on the five sites ranged from 81.6 to 350 spores per 20 g soil.Twenty-three AMF species from 9 genera were identified in total,and Glomeraceae was the dominant family.The findings of our study suggested a high AMF diversity harbored by olive growing in different areas of the Yunnan Province,Southwestern China.Furthermore,the hyphal colonization in roots positively correlated with soil pH and EC.The arbuscule colonization in olive roots negatively correlated with soil pH,EC,OM,TN,TP and AN.The spore density positively correlated with OM,TN,AN,AP and sand content.Finally,the Shannon index of AMF in the rhizosphere soil positively correlated with the clay content,but negatively correlated with soil pH,TN and silt content.The high diversity of autochthonous AMF in Yunnan is promising for screening AMF isolates for utilization in the efficient cultivation of this crop.展开更多
Reconstruction of ancient atmospheric conditions through the analysis of precipitation patterns is a novel endeavor in the study of paleoclimate. A new approach is now available for a quantitative reconstruction of Pa...Reconstruction of ancient atmospheric conditions through the analysis of precipitation patterns is a novel endeavor in the study of paleoclimate. A new approach is now available for a quantitative reconstruction of Paleogene atmospheric hydrological conditions in High Arctic. It is based on 1） the discovery of exceptionally-preserved Paleogene plant fossils from the Canadian Arctic which yielded in situ labile biomolecules 2） the development of compound-specific hydrogen isotope analysis which can be applied to small amount of plant material and 3） taxon-specific apparent hydrogen isotope fractionation factors obtained from empirical measurement. A new moisture recycling model is established to explain the reconstructed paleohydrologic pattern in the High Arctic during Paleogene.展开更多
文摘Arbuscular mycorrhizal fungi(AMF)play a vital role in plant productivity and ecosystem functions.However,their responses to abiotic factors(i.e.,climate,physiography,and soil properties)are unknown,especially across climatic gradients and slope aspects in arid and semi-arid ecosys-tems.In this study,using 60 composite soil samples,direct and indirect effects of climate factors and slope aspects on AMF diversity,composition and spore density were studied.The findings indicate that climate has a more direct influ-ence on soil properties(P<0.001)in comparison to slope aspect(P=0.449).In contrast,climate significantly affected AMF diversity and composition,with the highest diversity in dryer areas.Soil pH had the highest correlation with different facets of AMF diversity.Structural equation modeling(SEM)indicated that only a small part of the variation in AMF diversity and spore density could be explained by climate characteristics,slope aspect and soil properties.Based on SEM results,climate was the most important determinant of AMF diversity and spore density;slope aspect had a less critical role.The outputs suggest that variations in AMF diversity are derived by the direct effects of climate and the indirect effect of soil chemical properties.In addition,with increasing dryness,sporulation and AMF diversity increased.
基金funded by the Agricultural Science and Technology Independent Innovation Fund of Jiangsu Province of China[Grant No.CX(17)004]the National Special Fund for Forestry Scientific Research in the Public Interest(Grant No.201504406)+2 种基金Major Fund for Natural Science of Jiangsu Higher Education Institutions(Grant No.15KJA220004)Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)the Doctorate Fellowship Foundation of Nanjing Forestry University(2169125)。
文摘Arbuscular mycorrhizal fungi(AMF)form a near-ubiquitous mutualistic association with roots to help plants withstand harsh environments,and play a key role in the establishment of coastal beach plant communities.Yet little is known about the structure and composition of AMF communities on coastal beaches of eastern China.In this study,we investigated the occurrence,community composition and diversity of AMF associated with common wild plants on a coastal beach of North Jiangsu,China.Almost all of the local wild species were colonized by AMF except for Chenopodium album L.Thirty-seven AMF species were isolated from the rhizosphere belonging to 12 genera in seven families.Glomus was the dominant genus and Funneliformis mosseae the dominant species.The colonization,spore composition and diversity of AMF were strongly related to edaphic factors.Sodium(Na^(+))ions in the soil significantly and negatively affected the colonization rate by AMF and both soil Na^(+)levels and pH had a significant negative effect on AMF spore density and evenness.However,there was a significant positive correlation between species richness and total organic carbon.The results provide insights into soil factors affecting native AMF communities in coastal beach habitats which could benefit vegetation recovery and soil reclamation efforts.
文摘In conversion of the integrated slant column amount of atmospheric ozone(O_3)measured by the ground-based spectrometer technique during twilight to the vertical quantity,the air-mass factor(AMF)is an important parameter.In this work,calculations of AMF for ozone were performed for different atmospheres.It is shown that the O_3 AMF has seasonal variations with the minimum at the beginning of spring and the maximum in summer due to the seasonal change in the vertical distributions of O_3.A parameterization relation is obtained between O_3 AMF and optical thickness of stratospheric volcanic aerosols based on the Monte-Carlo radiative transfer simulations.
基金supported by the National Natural Science Foundation of China(31760222)State Forestry Administration of China 948 Project“Introduction of Olive Water and Fertilizer Precise Control Technology”(2014-4-23)the“Plant Nutrition and Mycorrhiza Research”Discipline Team Building Project of Yunnan Academy of Forestry and Grassland(LKYTD-2018-6).
文摘Olive(Olea europaea L.)is one of the most important and widely cultivated fruit trees,with high economic,ecological,cultural and scientific value.China began introducing and cultivating olive in the 1960s,and Yunnan Province is one of the main growing areas.Improving the cultivation and productivity of this tree crop species is an important challenge.Olive is a typical mycotrophic species and the potential of arbuscular mycorrhizal fungi(AMF)for this plant is well recognized;nevertheless,studies of olive AMF in China are still very limited.Roots and rhizosphere soils of olive were sampled from five representative growing sites in the Yunnan Province of China to investigate the AMF colonization status in the root systems,the AMF community in the olive orchards and the edaphic factors influencing the arbuscular mycorrhizal(AM)parameters.Root samples of olive trees from different growing sites generally showed AMF colonization,suggesting that autochthonous AMF manifest a high efficiency in colonizing the roots of olive plants.The spore density on the five sites ranged from 81.6 to 350 spores per 20 g soil.Twenty-three AMF species from 9 genera were identified in total,and Glomeraceae was the dominant family.The findings of our study suggested a high AMF diversity harbored by olive growing in different areas of the Yunnan Province,Southwestern China.Furthermore,the hyphal colonization in roots positively correlated with soil pH and EC.The arbuscule colonization in olive roots negatively correlated with soil pH,EC,OM,TN,TP and AN.The spore density positively correlated with OM,TN,AN,AP and sand content.Finally,the Shannon index of AMF in the rhizosphere soil positively correlated with the clay content,but negatively correlated with soil pH,TN and silt content.The high diversity of autochthonous AMF in Yunnan is promising for screening AMF isolates for utilization in the efficient cultivation of this crop.
基金funded in part by the CAS/SAFEA International Partnership Program for Creatine Research Teams,the Pilot Project of Knowledge Innovation,CAS the Major Basis Research Projects(2006CB806400)+1 种基金the National Science Foundation of China(40402002)the American Chemical Society Petroleum Research Funds,and a NASA RI Space Grant
文摘Reconstruction of ancient atmospheric conditions through the analysis of precipitation patterns is a novel endeavor in the study of paleoclimate. A new approach is now available for a quantitative reconstruction of Paleogene atmospheric hydrological conditions in High Arctic. It is based on 1） the discovery of exceptionally-preserved Paleogene plant fossils from the Canadian Arctic which yielded in situ labile biomolecules 2） the development of compound-specific hydrogen isotope analysis which can be applied to small amount of plant material and 3） taxon-specific apparent hydrogen isotope fractionation factors obtained from empirical measurement. A new moisture recycling model is established to explain the reconstructed paleohydrologic pattern in the High Arctic during Paleogene.
