Objective To investigate the diversity and the distribution of host animal species of hantavirus and the effect on human health in Jiuhua Mountain area,China.Methods The host animal species of hantavirus was surveyed ...Objective To investigate the diversity and the distribution of host animal species of hantavirus and the effect on human health in Jiuhua Mountain area,China.Methods The host animal species of hantavirus was surveyed by using the trap method and the species diversity was evaluated by using the Simpson,Shannon-Weaner,and Pielou indices.Hantavirus antigens or antibodies in lung and blood samples of all the captured host animals were detected by direct or indirect immunofluorescence.Results Nine animal species of hantavirus were distributed in the forest ecosystem of Jiuhua Mountain.Of these,Niviventer confucianus and Apodemus agrarius were predominant,and N.confucianus,Rattus norvegicus,and Mus musculus had relatively large niche breadth index values.The host animals in the eastern and western mountain regions shared similar biodiversity index characteristics,predominant species,and species structures.Hantavirus was detected in 5 host animal species in Jiuhua Mountain area,the carriage rate of hantavirus was 6.03%.The average density of host animals in forest areas of the mountainous area was only 2.20%,and the virus infection rate in the healthy population was 2.33%.Conclusion The circulation of hantavirus was low in the forest areas of Jiuhua Mountain and did not pose a threat to human health.展开更多
The prefrontal cortex of a human full termnewborn infant just after accidental death was studies by mcans of immunocytochemical technique with antibody directedagainst GABA(Immunonuclear Corp.)and ABC kit(Vector)。GAB...The prefrontal cortex of a human full termnewborn infant just after accidental death was studies by mcans of immunocytochemical technique with antibody directedagainst GABA(Immunonuclear Corp.)and ABC kit(Vector)。GABA-containing neurons were found over all layers and all were nonpyramidal cells.The laminar distribution of GABA-containing ne-urons was not even between different layers,density in laye Ⅱ was prominently higher than any other layers,density in layer Ⅲ and layer Ⅳ was higher than that in layer V and Ⅵ.展开更多
Background:Assessing functional diversity to identify its spatial patterns and drivers is an important step towards understanding the adaptive capacity of ecosystems to environmental change. However, until now, these ...Background:Assessing functional diversity to identify its spatial patterns and drivers is an important step towards understanding the adaptive capacity of ecosystems to environmental change. However, until now, these mechanisms were poorly understood in the temperate forests of northeastern China, which prevented the development of new management methods aimed at increasing functional trait diversity and thus ecological resilience.Methods:In this study, we mapped functional diversity distributions using a Kriging Interpolation Method. A specific random forest model approach was adopted to test the importance ranking of 18 variables in explaining the spatial variation of functional diversity. Three piecewise structural equation models (pSEMs) with forest types as random effects were constructed for testing the direct effects of climate, and the indirect effects of stand structure on functional diversity across the large study region. Specific causal relationships in each forest type were also examined using 15 linear structural equation models.Results:Although environmental filtering by climate is important, stand structure explains most of the functional variation of the forest ecosystems in northeastern China. Our study thus only partially supports the stressdominance hypothesis. Several abundant species determine most of the functional diversity, which supports the mass ratio hypothesis.Conclusions:Our results suggest that forest management aimed at increasing structural complexity can contribute to increased functional diversity, especially regarding the mixing of coniferous and broad-leaved tree species.展开更多
Yunnan's biodiversity is under considerable pressure and subtropical evergreen broad-leaved forests in this area have become increasingly fragmented through agriculture,logging,planting of economic plants,mining a...Yunnan's biodiversity is under considerable pressure and subtropical evergreen broad-leaved forests in this area have become increasingly fragmented through agriculture,logging,planting of economic plants,mining activities and changing environment.The aims of the study are to investigate climate changeinduced changes of subtropical evergreen broad-leaved forests in Yunnan and identify areas of current species richness centers for conservation preparation.Stacked species distribution models were created to generate ensemble forecasting of species distributions,alpha diversity and beta diversity for Yunnan's subtropical evergreen broad-leaved forests in both current and future climate scenarios.Under stacked species distribution models in rapid climate changes scenarios,changes of water-energy dynamics may possibly reduce beta diversity and increase alpha diversity.This point provides insight for future conservation of evergreen broad-leaved forest in Yunnan,highlighting the need to fully consider the problem of vegetation homogenization caused by transformation of water-energy dynamics.展开更多
基金supported by grants from the‘Twelfth Five-year Plan’from the Ministry of Science and Technology of China(2011BAD12B04-02)
文摘Objective To investigate the diversity and the distribution of host animal species of hantavirus and the effect on human health in Jiuhua Mountain area,China.Methods The host animal species of hantavirus was surveyed by using the trap method and the species diversity was evaluated by using the Simpson,Shannon-Weaner,and Pielou indices.Hantavirus antigens or antibodies in lung and blood samples of all the captured host animals were detected by direct or indirect immunofluorescence.Results Nine animal species of hantavirus were distributed in the forest ecosystem of Jiuhua Mountain.Of these,Niviventer confucianus and Apodemus agrarius were predominant,and N.confucianus,Rattus norvegicus,and Mus musculus had relatively large niche breadth index values.The host animals in the eastern and western mountain regions shared similar biodiversity index characteristics,predominant species,and species structures.Hantavirus was detected in 5 host animal species in Jiuhua Mountain area,the carriage rate of hantavirus was 6.03%.The average density of host animals in forest areas of the mountainous area was only 2.20%,and the virus infection rate in the healthy population was 2.33%.Conclusion The circulation of hantavirus was low in the forest areas of Jiuhua Mountain and did not pose a threat to human health.
文摘The prefrontal cortex of a human full termnewborn infant just after accidental death was studies by mcans of immunocytochemical technique with antibody directedagainst GABA(Immunonuclear Corp.)and ABC kit(Vector)。GABA-containing neurons were found over all layers and all were nonpyramidal cells.The laminar distribution of GABA-containing ne-urons was not even between different layers,density in laye Ⅱ was prominently higher than any other layers,density in layer Ⅲ and layer Ⅳ was higher than that in layer V and Ⅵ.
基金supported by the Program of National Natural Science Foundation of China (No. 31971650)the Key Project of National Key Research and Development Plan (No. 2017YFC0504104)Beijing Forestry University Outstanding Young Talent Cultivation Project(No. 2019JQ03001)
文摘Background:Assessing functional diversity to identify its spatial patterns and drivers is an important step towards understanding the adaptive capacity of ecosystems to environmental change. However, until now, these mechanisms were poorly understood in the temperate forests of northeastern China, which prevented the development of new management methods aimed at increasing functional trait diversity and thus ecological resilience.Methods:In this study, we mapped functional diversity distributions using a Kriging Interpolation Method. A specific random forest model approach was adopted to test the importance ranking of 18 variables in explaining the spatial variation of functional diversity. Three piecewise structural equation models (pSEMs) with forest types as random effects were constructed for testing the direct effects of climate, and the indirect effects of stand structure on functional diversity across the large study region. Specific causal relationships in each forest type were also examined using 15 linear structural equation models.Results:Although environmental filtering by climate is important, stand structure explains most of the functional variation of the forest ecosystems in northeastern China. Our study thus only partially supports the stressdominance hypothesis. Several abundant species determine most of the functional diversity, which supports the mass ratio hypothesis.Conclusions:Our results suggest that forest management aimed at increasing structural complexity can contribute to increased functional diversity, especially regarding the mixing of coniferous and broad-leaved tree species.
基金Acknowledgments The authors thank Ming-Gang Zhang and Katharina Filz for suggestions about problem of multicollinearity and thank Damien Georges for suggestions about modeling.
文摘Yunnan's biodiversity is under considerable pressure and subtropical evergreen broad-leaved forests in this area have become increasingly fragmented through agriculture,logging,planting of economic plants,mining activities and changing environment.The aims of the study are to investigate climate changeinduced changes of subtropical evergreen broad-leaved forests in Yunnan and identify areas of current species richness centers for conservation preparation.Stacked species distribution models were created to generate ensemble forecasting of species distributions,alpha diversity and beta diversity for Yunnan's subtropical evergreen broad-leaved forests in both current and future climate scenarios.Under stacked species distribution models in rapid climate changes scenarios,changes of water-energy dynamics may possibly reduce beta diversity and increase alpha diversity.This point provides insight for future conservation of evergreen broad-leaved forest in Yunnan,highlighting the need to fully consider the problem of vegetation homogenization caused by transformation of water-energy dynamics.