Microbial application is an efficient, economical, and ecofriendly method for remediating black-odorous rivers. In this study, the field treatment effect and microbial community changes were monitored during remediati...Microbial application is an efficient, economical, and ecofriendly method for remediating black-odorous rivers. In this study, the field treatment effect and microbial community changes were monitored during remediation by the acclimated complex microorganisms of a typical black-odorous stream. After the treatment, the total phosphorus and ammonia contents decreased by 74.0% and 76.3% and the concentrations of dissolved oxygen increased from 1.65 to 4.90 mg/L, indicating the effectiveness of the acclimated composite microorganisms. The proportion of Bacteroidetes decreased significantly by 48.1% and that of Firmicutes increased by 2.23% on average, and the microbial diversity index first increased and then tended to be uniform. Redundancy analysis demonstrated that the pH,dissolved oxygen, and oxidation-reduction potential together determined the composition of the microbial communities(p < 0.05). These findings showed that the acclimated composite microorganisms can effectively remediate the black odor.展开更多
Permafrost in Northeast China is highly sensitive to climate warming.Permafrost degradation significantly affects forest and vegetation ecosystems,as well as the safety of engineering projects and other man-made infra...Permafrost in Northeast China is highly sensitive to climate warming.Permafrost degradation significantly affects forest and vegetation ecosystems,as well as the safety of engineering projects and other man-made infrastructures.However,the permafrost change in the region is still unclear.This study uses metrological data from 258 weather stations,alongside reanalysis data,and other environmental data to investigate permafrost degradation and its related environmental impacts in Northeast China from the 1950s to 2010s.Results show that the total permafrost area decreased from 4.8×10^(5)to 3.1×10^(5)km^(2)from the 1950s to the 2010s.The southern limit of permafrost moved 0.1-1.1°northward,and its average elevation rose 160.5 m.During the study period,the degradation of predominantly continuous permafrost,and discontinuous and island permafrost was more pronounced than that of sparsely island permafrost.The south boundary of those three permafrost zones northward by 0-3.4°,0-5.5°and 0.4-1.1°,the average altitude raised by 339.2 m,208.3 m,67.1 m.The permafrost degradation shows the elevation and latitude zonality.Permafrost degradation is mainly caused by the rising of surface temperatures and the impacts of other environmental factors.The snowfall warming the ground of 1.1-10.2℃in cold seasons and rainfall cooling on surface conditions in warm seasons,those may result in temporal and spatial differences in permafrost degradation.However,there are lack of researches in the impact of environment factors on soil temperatures,moisture and permafrost degradation.展开更多
基金supported by the Science and Technology program of Yantai (No. 2017ZH095)。
文摘Microbial application is an efficient, economical, and ecofriendly method for remediating black-odorous rivers. In this study, the field treatment effect and microbial community changes were monitored during remediation by the acclimated complex microorganisms of a typical black-odorous stream. After the treatment, the total phosphorus and ammonia contents decreased by 74.0% and 76.3% and the concentrations of dissolved oxygen increased from 1.65 to 4.90 mg/L, indicating the effectiveness of the acclimated composite microorganisms. The proportion of Bacteroidetes decreased significantly by 48.1% and that of Firmicutes increased by 2.23% on average, and the microbial diversity index first increased and then tended to be uniform. Redundancy analysis demonstrated that the pH,dissolved oxygen, and oxidation-reduction potential together determined the composition of the microbial communities(p < 0.05). These findings showed that the acclimated composite microorganisms can effectively remediate the black odor.
基金supported by the National Natural Science Foundation of China(41771074,41690144)foundation for excellent youth scholars of Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences(FEYS2019002).
文摘Permafrost in Northeast China is highly sensitive to climate warming.Permafrost degradation significantly affects forest and vegetation ecosystems,as well as the safety of engineering projects and other man-made infrastructures.However,the permafrost change in the region is still unclear.This study uses metrological data from 258 weather stations,alongside reanalysis data,and other environmental data to investigate permafrost degradation and its related environmental impacts in Northeast China from the 1950s to 2010s.Results show that the total permafrost area decreased from 4.8×10^(5)to 3.1×10^(5)km^(2)from the 1950s to the 2010s.The southern limit of permafrost moved 0.1-1.1°northward,and its average elevation rose 160.5 m.During the study period,the degradation of predominantly continuous permafrost,and discontinuous and island permafrost was more pronounced than that of sparsely island permafrost.The south boundary of those three permafrost zones northward by 0-3.4°,0-5.5°and 0.4-1.1°,the average altitude raised by 339.2 m,208.3 m,67.1 m.The permafrost degradation shows the elevation and latitude zonality.Permafrost degradation is mainly caused by the rising of surface temperatures and the impacts of other environmental factors.The snowfall warming the ground of 1.1-10.2℃in cold seasons and rainfall cooling on surface conditions in warm seasons,those may result in temporal and spatial differences in permafrost degradation.However,there are lack of researches in the impact of environment factors on soil temperatures,moisture and permafrost degradation.
