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Journal of Environmental Sciences 2019年第7期31卷 214-224页

作者： Fangmin Chen Xiang Li Yan Yuan Yong Huang School of Environmental Science and Engineering Suzhou University of Science and Technology National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology

In order to reduce the amount of NO_3^-–N generated by the Anammox process, and alleviate the competition between denitrification and Anammox for NO_2^-–N in a single reactor, the preference of S^0 for reacting with coexisting NO_2^-–N and NO_3^-–N in the sulfur autotrophic denitrifying(SADN) process and the coupling effect of short-cut SADN and the Anammox process were studied. The results showed that S^0 preferentially reacted with NO_3^-to produce NO_2^-–N, and then reacted with NO_2^-–N when NO_3^-–N was insufficient, which could effectively alleviate the competition between SADN bacteria(SADNB) and Anammox bacteria(An AOB) for NO_2^-–N. After 170 days of operation, coupling between short-cut S^0-SADN and the Anammox process was first successfully achieved. SADNB converted the NO_3^-–N generated by the Anammox process into NO_2^-–N, which was once again available to An AOB. The total nitrogen removal efficiency eventually stabilized at over 95%, and the effluent NO_3^-–N was controlled within 10 mg/L, when high NH_4^+–N wastewater was treated by the Anammox process. Microbial community analysis further showed that Candidatus Brocadia and Thiobacillus were the functional microorganisms for An AOB and SADNB.

关键词： Anammox Sulfur autotrophic denitrification with S0 as electron donor (S0-SADN) Coupling Enhanced nitrogen removal

Distribution, residence time, autotrophic production, and heterotrophic removal of DOP in the Mirs Bay, northern South China Sea

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Acta Oceanologica Sinica 2019年第8期38卷 17-26页

作者： Huaming Shi Yu Ma Xulu Li Xiaoyong Shi Junxiao Zhang College of Environmental Science and Engineering Ocean University of China Qingdao 266100 China South China Sea Marine Survey and Technology Center Ministry of Natural Resources Guangzhou 510300 China National Marine Hazard Mitigation Service Ministry of Natural Resources Beijing 100194 China

The importance of dissolved organic phosphorus(DOP) as a potential nutrient source for primary producers in marine systems has been recognized for up to eight decades, but currently, the understanding of the biogeochemistry of DOP is in its infancy. In the present study, monthly data between 2000 and 2014 were used to analyze the temporal and spatial distributions of DOP in the Mir Bay, the northern South China Sea. The DOP residence time(TDOP) was also investigated using a simple regression analysis in combination with chlorophyll a(Chl a) measurements while excess DOP(ΔDOP), produced by the biogeochemical processes of autotrophic production and heterotrophic removal, was determined using a two-component mixing mass-balance model in combination with salinity measurements. The results showed that the DOP concentration was(0.017±0.010) mg/L higher in the surface-water compared with the bottom-water and higher in the inner Tolo Harbour and waters adjacent to Shatoujiao compared with the main zone of the bay. Although seasonal changes and annual variability in the DOP were small, the surface DOP concentration was higher in the wet season(April–September)than in the dry season(October–March) due to the impacts of seaward discharges and atmospheric deposition into the bay. Measurement and regression results showed that the DOP release rate from phytoplankton production was about 1.83(gP)/(gChl a) and the TDOP was about 7 d, which implied that the DOP cycle in the bay was rapid. The ΔDOP was calculated from the model to be about 0.000 mg/L in the main zone of the bay and about 0.002 mg/L in the inner Tolo Harbour and waters adjacent to Shaotoujiao, suggesting that the autotrophic production of DOP was almost balanced by the heterotrophic removal in the main zone of the bay and dominated in the inner Tolo Harbour and waters adjacent to Shaotoujiao. In conclusion, the Mirs Bay is very productive and fairly heterotrophic.

关键词： dissolved organic phosphorus temporal and spatial distributions residence time autotrophic production heterotrophic removal Mirs Bay northern South China Sea

Rapid Acclimation of Methanogenic Granular Sludge into autotrophic Partial Denitrification Granules

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China Petroleum Processing & Petrochemical Technology 2019年第3期21卷 68-73页

作者： Liu Chunshuang Li Xuechen Zhang Xiaofei Bai Xue Guo Yadong Wang Yongxing Zhao Chaocheng College of Chemical Engineering China University of PetroleumQingdao 266580China CNPC Research Institute of Safety and Environmental Technology Beijing 102206

Rapid formation of autotrophic partial denitrification(APD)granules is of practical interest to start up an expanded granular sludge bed reactor for wastewater *** study demonstrates that methanogenic granules can be easily acclimated into autotrophic partial denitrification granules in one day,with the ability to remove 82%of 2.7 kg-S/(m^3·d)sulfide into S^0 and to convert 97%of 0.9 kg-N/(m^3·d)nitrate into nitrite,which can provide a promising feedstock for anaerobic ammonia oxidation *** *** essential for S^0 *** high loadings,the abundance of Arcobacter ***,while on the contrary the abundance of unclassified_p_Firmicutes increased,leading to the deterioration of autotrophic partial denitrification *** granules performance could be recovered by adopting the strategies of properly reducing the influent loadings.

关键词： methanogenic granules nitrite accumulation autotrophic partial denitri fication sul fide

Heterotrophic and autotrophic Soil Respiration under Simulated Dormancy Conditions

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Open Journal of Forestry 2015年第3期5卷 274-286页

作者： Daniel Beverly Scott Franklin School of Biological Sciences University of Northern Colorado Greeley CO USA Botany Department University of Wyoming Laramie WY USA

Carbon cycling research has increased over the past 20 years, but less is known about the primary contributors to soil respiration (i.e. heterotrophic and autotrophic) under dormant conditions. It is understood that soil CO2 effluxes are significantly lower during the winter of temperate ecosystems and assumed microorganisms dominate efflux origination. We hypothesized that heterotrophic contributions would be greater than autotrophic under simulated dormancy conditions. To test this hypothesis, we designed an experiment with the following treatments: combined autotrophic heterotrophic respiration, heterotrophic respiration, autotrophic respiration, no respiration, autotrophic respiration in vermiculite, and no respiration in vermiculite. Engelmann spruce seedlings and soil substrates were placed in specially designed respiration chambers and soil CO2 efflux measurements were taken four times over the course of a month. Soil microbial densities and root volumes were measured for each chamber after day thirty-three. Seedling presence resulted in significantly higher soil CO2 efflux rates for all soil substrates. autotrophic respiration treatments were not representative of solely autotrophic soil CO2 efflux due to soil microbial contamination of autoclaved soil substrates;however, the mean autotrophic contributions averaged less than 25% of the total soil CO2 efflux. Soil microorganism communities were likely the primary contributor to soil CO2 efflux in simulated dormant conditions, as treatments with the greatest proportions of microbial densities had the highest soil CO2 efflux rates. Although this study is not directly comparable to field dormant season soil CO2 effluxes of Engelmann spruce forest, as snowpack is not maintained throughout this experiment, relationships, and metrics from such small-scale ecosystem component processes may yield more accurate carbon budget models.

关键词： Dormant autotrophic Respiration Heterotrophic Respiration Dormant Soil CO2 Efflux Soil Respiration Engelmann Spruce

Oxidation behavior of ammonium in a 3-dimensional biofilm-electrode reactor

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Journal of Environmental Sciences 2013年第12期25卷 2403-2409页

作者： Jinjing Tang Jinsong Guo Fang Fang Youpeng Chen Lijing Lei Lin Yang Key Laboratory of Three Gorges Reservoir Region’s Eco-Environment (Ministry of Education) Chongqing University School of Chemistry and Chemical Engineering Chongqing University

Excess nitrogenous compounds are detrimental to natural water systems and to human health. To completely realize autohy- drogenotrophic nitrogen removal, a novel 3-dimensional biofilm-electrode reactor was designed. Titanium was electroplated with ruthenium and used as the anode. Activated carbon fiber felt was used as the cathode. The reactor was separated into two chambers by a permeable membrane. The cathode chamber was filled with granular graphite and glass beads. The cathode and cathode chamber were inhabited with domesticated biofilm. In the absence of organic substances, a nitrogen removal efficiency of up to 91% was achieved at DO levels of 3.42 ± 0.37 mg/L when the applied current density was only 0.02 mA/cm^2. The oxidation of ammonium in biofilmelectrode reactors was also investigated. It was found that ammonium could be oxidized not only on the anode but also on particle electrodes in the cathode chamber of the biofilm-electrode reactor. Oxidation rates of ammonium and nitrogen removal efficiency were found to be affected by the electric current loading on the biofilm-electrode reactor. The kinetic model of ammonium at different electric currents was analyzed by a first-order reaction kinetics equation. The regression analysis implied that when the current density was less than 0.02 mA/cm^2, ammonium removal was positively correlated to the current density. However, when the current density was more than 0.02 mA/cm^2, the electric current became a limiting factor for the oxidation rate of ammonium and nitrogen removal efficiency.

关键词： autotrophic biofilm-electrode nitrogen removal ammonium oxidation behavior

Biological conversion pathways of sulfate reduction ammonium oxidation in anammox consortia

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Frontiers of Environmental Science & Engineering 2020年第3期14卷 15-25页

作者： Zhen Bi Deqing Wanyan Xiang Li Yong Huang National and Local Joint Engineering Laboratory for Municipal Sewage Resource Utilization Technology Suzhou 215002China School of Environment Science and Engineering Suzhou University of Science and TechnologySuzhou 215002China

For over two decades,sulfate reduction with ammonium oxidation(SRAO)had been reported from laboratory *** was considered an autotrophic process mediated by anammox bacteria,in which ammonium as electron donor was oxidized by the electron acceptor *** process had been attributed to observed transformations of nitrogenous and sulfiirous compounds in natural *** obtained differed largely for the conversion mole ratios(ammonium/sulfate),and even the intermediate and final products of sulfate ***,the hypothesis of biological conversion pathways of ammonium and sulfate in anammox consortia is *** this study,continuous reactor experiments(with working volume of 3.8L)and batch tests were conducted under normal anaerobic(0.2

关键词： Anammox bacteria autotrophic Biological conversion Sulfate reducing am m onium oxidation (SRAO)

Short-term effects of nitrogen deposition on soil respiration components in two alpine coniferous forests, southeastern Tibetan Plateau

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Journal of Forestry Research 2019年第3期30卷 1029-1041页

作者： Jian Wang Genxu Wang Yu Fu Xiaopeng Chen Xiaoyan Song Land and Resource College China West Normal University Nanchong 637002SichuanPeople’s Republic of China Key Laboratory of Mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences#9Block 4 Renminnanlu RoadWuhou DistrictChengdu 610041 People’s Republic of China Department of Politics and Administration China West Normal UniversityNanchong 637002SichuanPeople’s Republic of China Graduate University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

Nitrogen (N) deposition to alpine forest ecosystems is increasing gradually, yet previous studies have seldom reported the effects of N inputs on soil CO2 flux in these ecosystems. Evaluating the effects of soil respiration on N addition is of great significance for understanding soil carbon (C) budgets along N gradients in forest ecosystems. In this study, four levels of N (0, 50, 100, 150 kg N ha^-1 a^-1) were added to soil in a Picea baifouriana and an Abies georgei natural forest on the Tibetan Plateau to investigate the effect of the N inputs on soil respiration. N addition stimulated total soil respiration (Rt) and its components including heterotrophic respiration (Rh) and autotrophic respiration (Ra);however, the promoted effects declined with an increase in N application in two coniferous forests. Soil respiration rate was a little greater in the spruce forest (1.05 μmol CO2 m^-2 s^-1) than that in the fir forest (0.97 μmol CO2 m^-2 s^-1). A repeated measures ANOVA indicated that N fertilization had significant effects on Rt and its components in the spruce forest and Rt in the fir forest, but had no obvious effect on Rh or Ra in the fir forest. Rt and its components had significant exponential relationships with soil temperature in both forests. N addition also increased temperature sensitivity (Q10) of Rt and its components in the two coniferous forests, but the promotion declined as N in put increased. Important, soil moisture had great effects on Rt and its components in the spruce forest (P0.05). Following N fertilization, Ra was significantly and positively related to fine root biomass, while Rh was related to soil enzymatic activities in both forests. The mechanisms underlying the effect of simulated N deposition on soil respiration and its components in this study may help in forecasting C cycling in alpine forests under future levels of reactive N deposition.

关键词： N addition Heterotrophic soil respiration autotrophic soil respiration Q10 Alpine forest ecosystem

Acclimatization of in Vitro-derived Dendrobium

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Horticultural Plant Journal 2017年第3期3卷 110-124页

作者： Jaime A.Teixeira da Silva Mohammad Musharof Hossain Madhu Sharma Judit Dobránszki Jean Carlos Cardoso ZENG Songjun Miki-cho post office Department of Botany University of Chittagong Division of Biotechnology CSIR-Institute of Himalayan Bioresource Technology Research Institute of Nyíregyháza University of Debrecen Centro de Ciências Agrárias UFSCar Guangdong Provincial Key Laboratory of Applied Botany South China Botanical GardenChinese Academy of Sciences

The successful ex vitro establishment of Dendrobium plantlets raised in vitro determines the quality of the end product(cut flowers or potted plants) in commercial production for economic gain. When in vitro Dendrobium plantlets are transplanted from the culture room to greenhouse conditions, they may desiccate or wilt rapidly and can die as a result of changes in the environment, unless substantial precautions are taken to adapt plantlets to a new environment. The acclimatization of in vitro-grown Dendrobium plantlets to an ex vitro environment by gradually weaning them towards ambient relative humidity and light levels facilitates better survival of young and physiologically sensitive *** plantlets raised in vitro must thus undergo a period of acclimatization or transitional development to correct anatomical abnormalities and to enhance their physiological performance to ensure survival under ex vitro conditions. The most common approach to improve the survival of Dendrobium plantlets upon transfer to an ex vitro environment is their gradual adaptation to that environment. Under such conditions, plants convert rapidly from a heterotrophic or photomixotrophic state to an autotrophic growth, develop a fully functional root system,and better control their stomatal and cuticular transpiration. Gradual adaptation is carried out in a greenhouse by decreasing relative humidity using fog or mist chambers and by increasing light intensity using shading techniques. This review details the acclimatization and ex vitro survival of Dendrobium plants produced in vitro. This advice is also useful for other orchids.

关键词： Orchidaceae acclimation hardening autotrophic light intensity medicinal orchid relative humidity