Graphene oxide(GO),a carbon nanomaterial that is widely used in the environment and other industries,may pose potential risks to ecosystems,especially the soil ecosystem.Some soils in Northeast China are frequently po...Graphene oxide(GO),a carbon nanomaterial that is widely used in the environment and other industries,may pose potential risks to ecosystems,especially the soil ecosystem.Some soils in Northeast China are frequently polluted with cadmium(Cd) metal.However,there is no study on the influence of GO on the Cd-contaminated soil microbial community and soil chemical properties.In this study,Cd(100 mg kg^(-1))-polluted soils were treated with different concentrations of GO(0,25,50,150,250,and 500 mg L^(-1),expressed as T1,T2,T3,T4,T5,and T6,respectively) for 40 days.The treatment without Cd pollution and GO served as the control(CK).Then,we investigated the influence of the GO concentrations on the bacterial community and chemical properties of Cd-polluted Haplic Cambisols,the zonal soil in Northeast China.After GO addition,the richness and diversity indexes of the bacterial community in Cd-contaminated Haplic Cambisols initially increased by 0.05-33.92% at 25 mg L^(-1),then decreased by0.07-2.37% at 50 mg L^(-1),and then increased by 0.01-24.37%within 500 mg L^(-1) again.The species and abundance of bacteria varied with GO concentration,and GO significantly increased bacterial growth at 25 and 250 mg L^(-1).GO treatments influenced the bacterial community structure,and the order of similarity of the bacterial community structure was as follows:T4=T5> T1=T6> T2> T3> CK.Proteobacteria and Acidobacteria were the dominant bacteria,accounting for 36.0% and 26.2%,respectively,of soil bacteria.Different GO treatments also significantly affected the metabolic function of bacteria and further influenced the diversity of the bacterial community structure by affecting several key soil chemical properties:soil pH,organic matter and available potassium,phosphorus,and cadmium.Our results provide a theoretical basis for scientific and comprehensive evaluation of the environmental impacts of GO on the zonal forest soils of Northeast China.展开更多
Under the new situation, news and propaganda work must hold high the banner around the overall situation, serve the people, make reform and innovation, adhere to the correct guidance of public opinion, to improve the ...Under the new situation, news and propaganda work must hold high the banner around the overall situation, serve the people, make reform and innovation, adhere to the correct guidance of public opinion, to improve the ability to guide public opinion, to create a good public opinion environment, to better play and publicize the party＇ s ideas, to promote social justice, to access to social conditions public opinion, to guide social hot spots, to divert the public mood, to improve the important role of public opinion. We should put the improvement of the ability to guide public opinion in a prominent position, conduct in-depth research, and come up with concrete measures to achieve new results. We must adhere to the Party＇ s principles; firmly grasp the correct guidance of public opinion. Guiding correctly public opinion will benefit the country, party and people; guiding media wrong will make damage to China, party and people. To firmly establish political awareness, the overall sense of responsibility, position sense, we should put adhering to the correct orientation in the first place on the news and propaganda work.展开更多
基金supported financially by the National Natural Science Foundation of China (31370613)the Fundamental Research Funds for the Central Universities(2572019CP15)。
文摘Graphene oxide(GO),a carbon nanomaterial that is widely used in the environment and other industries,may pose potential risks to ecosystems,especially the soil ecosystem.Some soils in Northeast China are frequently polluted with cadmium(Cd) metal.However,there is no study on the influence of GO on the Cd-contaminated soil microbial community and soil chemical properties.In this study,Cd(100 mg kg^(-1))-polluted soils were treated with different concentrations of GO(0,25,50,150,250,and 500 mg L^(-1),expressed as T1,T2,T3,T4,T5,and T6,respectively) for 40 days.The treatment without Cd pollution and GO served as the control(CK).Then,we investigated the influence of the GO concentrations on the bacterial community and chemical properties of Cd-polluted Haplic Cambisols,the zonal soil in Northeast China.After GO addition,the richness and diversity indexes of the bacterial community in Cd-contaminated Haplic Cambisols initially increased by 0.05-33.92% at 25 mg L^(-1),then decreased by0.07-2.37% at 50 mg L^(-1),and then increased by 0.01-24.37%within 500 mg L^(-1) again.The species and abundance of bacteria varied with GO concentration,and GO significantly increased bacterial growth at 25 and 250 mg L^(-1).GO treatments influenced the bacterial community structure,and the order of similarity of the bacterial community structure was as follows:T4=T5> T1=T6> T2> T3> CK.Proteobacteria and Acidobacteria were the dominant bacteria,accounting for 36.0% and 26.2%,respectively,of soil bacteria.Different GO treatments also significantly affected the metabolic function of bacteria and further influenced the diversity of the bacterial community structure by affecting several key soil chemical properties:soil pH,organic matter and available potassium,phosphorus,and cadmium.Our results provide a theoretical basis for scientific and comprehensive evaluation of the environmental impacts of GO on the zonal forest soils of Northeast China.
文摘Under the new situation, news and propaganda work must hold high the banner around the overall situation, serve the people, make reform and innovation, adhere to the correct guidance of public opinion, to improve the ability to guide public opinion, to create a good public opinion environment, to better play and publicize the party＇ s ideas, to promote social justice, to access to social conditions public opinion, to guide social hot spots, to divert the public mood, to improve the important role of public opinion. We should put the improvement of the ability to guide public opinion in a prominent position, conduct in-depth research, and come up with concrete measures to achieve new results. We must adhere to the Party＇ s principles; firmly grasp the correct guidance of public opinion. Guiding correctly public opinion will benefit the country, party and people; guiding media wrong will make damage to China, party and people. To firmly establish political awareness, the overall sense of responsibility, position sense, we should put adhering to the correct orientation in the first place on the news and propaganda work.
