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nitrogen transformation processes in soil along a High Arctic tundra transect

Advances in Polar Science 2023年第2期34卷 105-124页

作者： GUO Mengjie WANG Qing ZHANG Wanying JIAO Yi SUN Bowen HOU Lijun ZHU Renbin Institute of Polar Environment&Anhui Province Key Laboratory of Polar Environment and Global Change School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China State Key Laboratory of NBC Protection for Civilian Beijing 102205China Terrestrial Ecology Section Department of BiologyCopenhagen UniversityCopenhagenØDK-2100Denmark State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200241China

Soil nitrogen(N)transformation processes in the High Arctic tundra are poorly understood even though nitrogen is one of the main limiting *** analyzed soil samples collected along a High Arctic tundra transect to investigate spatial variability in key nitrogen transformation processes,functional gene abundances,ammonia-oxidizing archaea(AOA)community structures,and key nitrogen transformation *** potential denitrification rates were higher than the nitrification rates in the soil samples,although nitrification may still regulate N2O emissions from tundra *** nutrient(total carbon,total organic carbon,total nitrogen,and NH_(4)^(+)-N)contents were important determinants of spatial variability in the potential denitrification rates of soil along the tundra *** total sulfurcontent was the main variable controlling potential nitrification processes,probably in association with sulfate-reducing *** nitrate content was the main variable affecting potential dissimilatory nitrate reduction to *** and ammonia-oxidizing bacteria amoA,nirS,and anammox 16S rRNA genes were found in all of the soil *** play more important roles than ammonia-oxidizing bacteria in *** bacteria may utilize NO_(2)^(-)produced through *** analysis indicated that the AOA amoA sequences could be grouped into eight unique operational taxonomic units(OTUs)with a 97%sequence similarity and were affiliated with three group 1.1b *** results indicated that heterogeneous environmental factors(e.g.,the carbon and nitrogen contents of soil)along the High Arctic tundra transect strongly affected the nitrogen transformation rate and relevant functional gene abundances in soil.

关键词： Arctic tundra soil nitrogen transformation nitrification denitrification functional gene abundance ammonia-oxidizing archaea

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Effects of muddy water irrigation with different sediment gradations on nitrogen transformation in agricultural soil of Yellow River Basin

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Water Science and Engineering 2022年第3期15卷 228-236页

作者： Li-na Chen Zi-long Zhao Guo-mian Guo Jiang Li Wen-bo Wu Fang-xiu Zhang Xiang Zhang College of Agricultural Science and Engineering Hohai UniversityNanjing 211100China Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education Hohai UniversityNanjing 210098China College of Environment Hohai UniversityNanjing 210098China Key Laboratory of Lower Yellow River Channel and Estuary Regulation of Ministry of Water Resources Zhengzhou 450003China Yellow River Institute of Hydraulic Research Zhengzhou 450003China

Muddy water irrigation has been widely practiced in the Yellow River Basin for agricultural production and is an important method of economical and intensive utilization of water *** this study,the effects of sediment gradation,sand content,and soil moisture content on nitrogen(N)transformation were studied through a series of experimental *** results indicated that muddy water irrigation significantly affected agricultural soil physical and biological properties as well as N *** bulk density,total porosity,pH,and microbial enzyme activities significantly correlated with N transformation as affected by the interaction between sediment and soil *** addition generally increased the soil bulk density and reduced the soil porosity and pH significantly,and the optimum moisture for promotion of the N transformation rate was 80%of the water-filled pore ***,muddy water irrigation has a potentially long-term influence on agricultural N cycles in semi-arid regions of northwestern *** could provide a theoretical basis for scientific and rational use of muddy water for irrigation.

关键词： Yellow River Basin Muddy water irrigation Soil properties nitrogen transformation Sediment

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The nitrogen transformation behavior based on the pyrolysis products of wheat straw

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Chinese Journal of Chemical Engineering 2024年第7期71卷 58-65页

作者： Shun Guo Yunfei Li Shengwei Tang Tao Zhang School of Chemical Engineering Sichuan UniversityChengdu 610065China

In order to provide basic design parameters for the industrial pyrolysis process,the transformation behavior of nitrogen was investigated using wheat straw as raw *** distributions of nitrogen in pyrolysis char,oil,and gas were obtained and the nitrogenous components in the products were analyzed systematically by X-ray photoelectron spectroscopy(XPS),pyrolysis-gas chromatography/mass spectrometry(Py-GC/MS)and thermogravimetric-Fourier transform infrared spectrometry(TG-FTIR).The nitrogen distribution ranges of the pyrolysis char,oil,and gas were 37.34%–54.82%,32.87%–40.94%and 10.20%–28.83%,*** nitrogen was retained in char at lower pyrolysis temperature and the nitrogen distribution of oil was from rise to decline with increasing *** most abundant N-containing compounds in three-phase products were pyrrole-N,amines,and HCN,*** addition,the transformation mechanism of nitrogen from wheat straw to pyrolysis products was concluded.

关键词： Pyrolysis nitrogen transformation Wheat straw Py-GC/MS TG-FTIR

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Elevated atmospheric CO_(2) impact on carbon and nitrogen transformations and microbial community in replicated wetland

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Ecological Processes 2020年第1期9卷 677-688页

作者： Dawei Jiang Lifei Chen Nan Xia Eyram Norgbey Desmond Ato Koomson Williams Kweku Darkwah College of Horticulture Jilin Agricultural UniversityChangchun 130118China Jilin Tiandiren Landscape Architecture Design Engineering Co.Ltd. Changchun 130117China Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes Ministry of EducationEnvironmental Engi neering DepartmentCollege of EnvironmentHohai University1 Xikang RoadGulou210098 NanjingChina

Background:Elevated atmospheric CO_(2) has direct and indirect influences on ecosystem *** impact of elevated atmospheric CO_(2) concentration on carbon and nitrogen transformations,together with the microbial community,was evaluated with water hyacinth(Eichhornia crassipes)in an open-top chamber replicated *** responses of nitrogen and carbon pools in water and wetland soil,and microbial community abundance were studied under ambient CO_(2) and elevated CO_(2)(ambient+200μL L^(−1)).Results:Total biomass for the whole plant under elevated CO_(2) increased by an average of 8%(p=0.022).Wetlands,with water hyacinth,showed a significant increase in total carbon and total organic carbon in water by 7%(p=0.001)and 21%(p=0.001),respectively,under elevated CO_(2) compared to that of ambient CO_(2).Increase in dissolved carbon in water correlates with the presence of wetland plants since the water hyacinth can directly exchange CO_(2) from the atmosphere to water by the upper epidermis of ***,the enrichment CO_(2) showed an increase in total carbon and total organic carbon concentration in wetland soil by 3%(p=0.344)and 6%(p=0.008),*** total nitrogen content in water increased by 26%(p=0.0001),while total nitrogen in wetland soil pool under CO_(2) enrichment decreased by 9%(p=0.011)due to increased soil microbial community abundance,extracted by phospholipid fatty acids,which was 25%larger in amount than that of the ambient ***:The study revealed that the elevated CO_(2) would affect the carbon and nitrogen transformations in wetland plant,water,and soil pool and increase soil microbial community abundance.

关键词： Elevated CO_(2) Carbon transformation nitrogen transformation Microbial community abundance Phospholipid fatty acids Open-top chamber

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Response of aerobic sludge to AHL-mediated QS:Granulation,simultaneous nitrogen and phosphorus removal performance

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Chinese Chemical Letters 2021年第11期32卷 3402-3409页

作者： Jia Shuai Xiaoling Hu Bin Wang Wanlin Lyu Rongfan Chen Wenbin Guo Hongyu Wang Dao Zhou School of Civil Engineering Wuhan UniversityWuhan 430072China

The effects of different species and concentrations’signal molecules on aerobic activated sludge system were investigated through batch *** showed that the fastest NH^(+)_(4)-N oxidization rate and the most extracellular polymeric substances(EPS)secretion were obtained by adding 5 nmol/L N-hexanoyl-l-homoserine lactone(C_(6)-HSL)into the aerobic activated *** study investigated the correlation among N-acyl-homoserine lactones-mediated quorum sensing(AHLs-mediated QS),nutrient removal performances and microbial communities with the long-term addition of 5 nmol/L C_(6)-*** was found that C_(6)-HSL-manipulation could enhance the stability and optimize the decontamination performance of aerobic granular sludge(AGS)*** compositions considerably shifted with long-term C_(6)-*** C_(6)-HSL-manipulation inhibited quorum quenching-related(QQ-related)activities and enhanced QS-related activities during the stable *** proposed C_(6)-HSL-manipulation might be a potential technology to inhibit the growth of harmful bacteria in AGS,which could provide a theoretical foundation for the realization of more stable biological wastewater treatments.

关键词： Quorum sensing(QS) Aerobic granular sludge(AGS) Simultaneous nitrogen and phosphorus removal(SNDPR) N-acyl-homoserine lactones(AHLs) N-hexanoyl-L-homoserine lactone(C_(6)-HSL) nitrogen transformation

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In-situ nitrogen fate in the vadose zone of different soil types and its implications for groundwater quality in the Huaihe River Basin,China

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Acta Geochimica 2020年第3期39卷 281-290页

作者： Rongfu Li Xiaohong Ruan Tianhai Ma Ying Bai Congqiang Liu MOE Key Laboratory of Surficial Geochemistry Nanjing UniversityNanjing 210023China Department of Water Science School of Earth Sciences and EngineeringNanjing UniversityNanjing 210023China Jinling Institute of Nanjing University Nanjing 210089China Institute of Surface-Earth System Science Tianjin UniversityTianjin 300072China

This paper focused on nitrate fate in the vadose zone(VZ)and its implications for groundwater vulnerability under different soil types in the agricultural area of Huaihe River Basin,*** compositions of nitrate(δ15N andδ18O)along with NO3-and Cl-concentrations were determined in the VZ-shallow groundwater continuum beneath silty-loam and silty-clay-loam,which are distinctive in texture and organic carbon(OC).In the soil zone(1 m in depth),however,the concurrent enrichment ofδ15N-NO3-andδ18O-NO3-indicated the occurrence of denitrification,which showed a dependence on subsoil ***,during wheat and maize land uses,denitrification removed as much as 76%-88%of the total nitrate where the subsoil was dominated by stratified OC-rich *** contrast,only 0%-28%of the nitrate was degraded via denitrification where the subsoil was composed of uniform,OC-depleted ***,inactive denitrification and higher permeability in the silty-loam VZ implied higher groundwater *** observation was consistent with the fact that groundwater NO3--N concentration beneath silty-loam(11.24 mg L-1)was over two times higher than that of the silty-clay-loam(5.32 mg L-1),where stricter fertilization management and conservation strategies should be applied to protect groundwater quality.

关键词： Vadose zone Silty-loam Silty-clay-loam nitrogen transformation Groundwater vulnerability Stable isotopes

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Responses of nitrogen cycling and related microorganisms to brackish wetlands formed by evapotranspiration

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Pedosphere 2024年第1期34卷 252-266页

作者： Jiaohui FANG Tianshu LU Jian LIU Shangbin HE Xiufeng YANG Huashan DOU Honghai ZHANG School of Life Sciences Qufu Normal UniversityQufu 273100China Environment Research Institute Shandong UniversityQingdao 266237China Hulunbuir Academy of Inland Lakes in Northern Cold&Arid Areas Hulunbuir 021000China

Elevated evapotranspiration due to warmer air temperature could raise salinity and nutrient levels of some inland wetlands, potentially impacting nitrogen cycling. To characterize the impact of high evapotranspiration on soil microbial nitrogen cycling in inland wetlands, we compared freshwater and brackish marsh(or non-marsh) wetlands in terms of sediment ammonia-oxidizing rate(AOR), denitrifying rate(DR), and related microbial communities in a typical inland basin, the Hulun Lake basin, in China. Results showed that marsh ecosystems(ME) exhibited 31% higher AOR and 65% higher DR than non-marsh ecosystems(NE). For NE, freshwater non-marsh wetland exhibited 12% higher AOR than brackish non-marsh wetland. This was probably due to the inhibitory effects of high NH_4~+ and salinity levels on ammonia-oxidizing archaea in brackish non-marsh wetland. Conversely, DR in brackish non-marsh wetland was 23% higher than that in freshwater non-marsh wetland, with total organic carbon(TOC) significantly influencing this difference,suggesting that the higher DR in brackish non-marsh wetland was mainly due to its higher TOC level. For ME, due to the direct and indirect interference of salinity, brackish marsh wetland displayed 26% lower AOR and 19% lower DR than freshwater marsh wetland. Besides, brackish wetlands harbored distinct ammonia-oxidizing and denitrifying microbial communities compared to freshwater wetlands. The assembly of these communities was dominated by stochastic processes, while brackish wetlands exhibited more prominent deterministic processes than freshwater wetlands. Overall, high evapotranspiration altered activities and community characteristics of ammonia oxidizers and denitrifiers in inland brackish wetlands by enhancing salinity and nutrient levels,while emergent plants occurring in ME could mitigate the adverse effects of salt stress of inland brackish wetlands on nitrogen cycling.

关键词： ammonia-oxidizing archaea ammonia-oxidizing bacteria aquatic plants denitrifying bacteria nitrogen transformation inland wetlands

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Coupling effects of water and nitrogen on photosynthetic characteristics,nitrogen uptake,and yield of sunflower under drip irrigation in an oasis

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International Journal of Agricultural and Biological Engineering 2021年第5期14卷 130-141页

作者： Tianyu Wang Zhenhua Wang Qiang Wu Jinzhu Zhang Lishuang Quan Bihang Fan Li Guo College of Water Resources and Architectural Engineering Shihezi UniversityShihezi 832000XinjiangChina Key Laboratory of Modern Water-saving Irrigation Corp Shihezi UniversityShihezi 832000XinjiangChina State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu 610065China

An experiment was conducted in an oasis area in northwest China to assess the coupling effects of water and nitrogen supply through drip irrigation on photosynthetic characteristics,nitrogen uptake,and yield of sunflower(Helianthus annuus L.),as well as the nitrate distribution in the root-zone *** experiment included three irrigation levels(210[W1],300[W2],and 390[W3]mm),three nitrogen levels(162[N1],232[N2],and 302[N3]kg/hm^(2)),and control treatment(no fertilization during whole growth period and only irrigated at the budding stage).A nitrogen content over-accumulation in the soil was observed under the low irrigation amount with high fertilizer supply,which cannot enhance the sunflowers’absorption of *** irrigation caused leach of the soil nitrogen,reduced nitrogen content in the root-zone soil(0-40 cm)and limited nitrogen uptake by the *** low irrigation amount with high fertilizer supply can increase the nitrogen content in the soil,it cannot enhance the sunflowers’absorption of *** the vegetative stage of sunflower growth,the accumulation of nitrogen in the organs was mainly concentrated in the leaves,while it was transferred to the flower disk at the reproductive growth *** coupling of water and nitrogen improved the transport of nitrogen from leaves and stems to the flower disk and promoted the formation of yield *** regression equations were established with irrigation and fertilization amount as independent variables,and seed rate,seed weight per flowerdisk,1000 grain weight,yield,water use efficiency and nitrogen partial factor productivity as dependent variables,*** regression and spatial analysis suggested that the irrigation amount of 241.62-253.35 mm and the fertilization application of 202.02-209.40 N kg/hm^(2)was a good irrigation strategy,under which all six factors exceed 75%of their maxima,and the yield of sunflower reached 3229.3 kg/hm^(2).

关键词： fertilization Helianthus annuus L. irrigation management nitrogen transformation nutrient uptake Xinjiang

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Effects of Glucose Addition on N transformations in Paddy Soils with a Gradient of Organic C Content in Subtropical China

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Agricultural Sciences in China 2010年第9期9卷 1309-1316页

作者： JIA Jun-xian LI Zhong-pei LIU Ming CHE Yu-ping State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 P.R. China Graduate University Chinese Academy of Sciences Beijing 100049 P.R.China College of Art and Science Shanxi Agricultural University Taigu 030801 P.R. China

To better understand the interaction of N transformation and exogenous C source and manage N fertilization, the effects of glucose addition on N transformation were determined in paddy soils with a gradient of soil organic C content. Changes in N mineralization, nitrification and denitrification, as well as their response to glucose addition were measured by incubation experiments in paddy soils derived from Quaternary red clay in subtropical China. Mineralization and denitrification were changed in order of increasing soil fertilities： high 〉 middle 〉 low. During the first week of incubation, net N mineralization and denitrification rates in paddy soil with high fertility were 1.9 and 1.1 times of those in soil with middle fertility and 5.3 and 2.9 times of those in soil with low fertility, respectively. Addition of glucose decreased net N mineralization by approximately 78.8, 109.2 and 177.4% in soils with high, middle and low fertility, respectively. However, denitrification rates in soils with middle and low fertility were increased by 14.4 and 166.2% respectively. The highest nitrate content among the paddy soils tested was 0.62 mg kg-1 and the highest nitrification ratio was 0.33%. Addition of glucose had no obvious effects on nitrate content and nitrification ratio. It was suggested that the intensity of mineralization and denitrification was quite different in soils with different fertility, and increased with increasing soil organic C content. Addition of glucose decreased mineralization, but increased denitrification, and the shifts were greater in soil with low than in soil with high organic C content. Neither addition of glucose nor inherent soil organic C had obvious effects on nitrification in paddy soils tested.

关键词： paddy soils of subtropical China soil fertility glucose addition nitrogen transformation

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Varying water column stability controls the denitrification process in a subtropical reservoir,Southwest China

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Journal of Environmental Sciences 2022年第1期34卷 208-219页

作者： Gaoyang Cui Xiao-Dong Li Siqi Li Shiyuan Ding Qinkai Li Mengdi Yang Hong Lv Yiyao Wang Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions Ministry of EducationCollege of Environment and PlanningHenan UniversityKaifeng 475004China Institute of Surface-Earth System Science School of Earth System ScienceTianjin UniversityTianjin 300072China Tianjin Key Laboratory of Earth’s Critical Zone Science and Sustainable Development in Bohai Rim Tianjin UniversityTianjin 300072China

Reservoirs are regarded as hotspots of nitrogen transformation and potential sources of nitrous oxide(N_(2)O).However,it remains unclear how the hydrological conditions due to dam construction control the processes of nitrogen transformation in reservoir *** address this issue,we examined the spatial-temporal characteristics of nitrate concentrations,δ^(15)N-NO_(3)^(-),δ^(18)O-NO_(3)^(-),δ^(18)O-H_(2)O,relative water column stability(RWCS),and related environmental factors in a subtropical eutrophic reservoir(Hongfeng Reservoir,HFR),Southwest *** found that denitrification was the most important nitrogen transformation process in the HFR and that higher denitrification intensity was associated with increased RWCS in summer,which suggested hydrological control of the denitrification *** contrast,low RWCS conditions favored the nitrification process in the HFR in ***,dissolved oxygen(DO;pnitrogen transformation processes in reservoirs.

关键词： Thermal stratification RWCS Denitrification nitrogen transformation Reservoir

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