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Soil microbial activity and community structure as affected by exposure to chloride and chloride-sulfate salts

Journal of Arid Land 2018年第5期10卷 737-749页

作者： ZHANG Qianqian Steven A WAKELIN liang yongchao CHU Guixin College of Life Science Shaoxing University Department of Resources and Environmental Science College of Agriculture/the Key Laboratory of Oasis Eco-agriculture of the Xinjiang Production and Construction Corps Shihezi University College of Resources and Environmental Sciences Nanjing Agricultural University Department of Forest Systems Scion Research Ministry of Education Key Laboratory of Environment Remediation and Ecological Health College of Environmental & Resource Sciences Zhejiang University

Mixed or chloride salty ions dominate in saline soils, and exert wide-ranging adversely affect on soil biological processes and soil functions. The objectives of this study were to（1） explore the impacts of mixed（0, 3, 6, 10, 20 and 40 g Cl–/SO42–salt/kg dry soil） and chloride（0, 1.5, 3, 5, 8 and 15 g Cl– salt/kg dry soil） salts on soil enzyme activities, soil physiological functional（Biolog） profiles and microbial community structure by using soil enzymatic, Biolog-Eco microplates as well as denaturing gradient gel electrophoresis（DEEG） methods, and（2） determine the threshold concentration of soil electronic conductivity（EC1：5） on maintaining the functional and structural diversity of soil microbial community. The addition of either Cl– or mixed Cl–/SO42–salt obviously increased soil EC, but adversely affected soil biological activities including soil invertase activity, soil microbial biomass carbon（MBC） and substrate-induced respiration（SIR）. Cl– salt showed a greater deleterious influence than mixed Cl–/SO42–salt on soil enzymes and MBC, e.g., the higher soil MBC consistently appeared with Cl–/SO42–instead of Cl– treated soil. Meanwhile, we found that SIR was more reliable than soil basal respiration（SBR） on explaining the changes of soil biological activity responsive to salt disturbance. In addition, microbial community structures of the soil bacteria, fungi, and Bacillus were obviously affected by both salt types and soil EC levels, and its diversity increased with increasing of mixed Cl–/SO42–salt rates, and then sharply declined down after it reached critical point. Moreover, the diversity of fungal community was more sensitive to the mixed salt addition than other groups. The response of soil physiological profiles（Biolog） followed a dose-response pattern with Cl–（R2=0.83） or mixed Cl–/SO42–（R2=0.89） salt. The critical threshold concentrations of salts for soil physiological function were 0.45 d S/m for Cl– and 1.26 d S/m for Cl–/SO42–, and those for soil

关键词： soil biological activity microbial diversit3T chloride salt mixed salt threshold concentration

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Impacts of soil organic matter, pH and exogenous copper on sorption behavior of norfloxacin in three soils

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Journal of Environmental Sciences 2009年第5期21卷 632-640页

作者： ZHANG Jie LI Zhaojun GE Gaofei SUN Wanchun liang yongchao WU Laosheng College of Natural Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 China Ministry of Agriculture Key Laboratory of Crop Nutrition and Fertilization Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences Beijing 100081 China Key Laboratory of Oasis Eco-Agriculture and College of Agriculture Shihezi University Shihezi 832003 China Department of Environmental Sciences University of California Riverside Riverside CA 92521 USA

Norfloxacin sorption and the factors （soil organic matter （SOM）, pH, and exogenous copper （Cu） influencing the sorption were investigated in a black soil （soil B）, a fluvo-aquic soil （soil F）, and a red soil （soil R）. With increasing norfloxacin concentrations, sorption amount of norfloxacin increased in both the bulk soils and their SOM-removed soils, but the sorption capacity of SOM-removed soils was higher than that of their corresponding bulk soils, indicating that the process of norfloxacin sorption in soil was influenced by the soil properties including SOM. The sorption data in all bulk soils and SOM-removed soils were fitted to Freundlich and Langmuir models. The correlation coefficients suggested that the experimental data fitted better to Freundlich equation than to Langmuir equation. Furthermore, the data from soil F and SOM-removed F could not be described by Langmuir equation. The norfloxacin sorption amount decreased in soil B and soil F, whereas it increased in soil R as solution pH increased. The maximum KD and Koc were achieved in soil R when the equilibrium solution pH was 6. The norfloxacin sorption was also influenced by the exogenous Cu^2＋, which depended on the soil types and Cu^2＋ concentrations. With increasing Cu^2＋ concentrations in solution, generally, sorption amount, KD and Koc for norfloxacin in soils increased and were up to a peak at 100 mg/L Cu^2＋, and then the sorption amount decreased regardless of norfloxacin levels.

关键词： copper norfloxacin pH soil organic matter sorption

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Elevated carbon dioxide stimulates nitrous oxide emission in agricultural soils: A global meta-analysis

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Pedosphere 2022年第1期32卷 3-14页

作者： Yilin DU Xinyu GUO Jinxing LI Yuankun LIU Jipeng LUO yongchao liang Tingqiang LI Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health College of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment Hangzhou 310058China National Demonstration Center for Experimental Environment and Resources Education Zhejiang UniversityHangzhou 310058China

Elevated carbon dioxide (CO_(2))(e CO_(2)) has been shown to affect the nitrous oxide (N_(2)O) emission from terrestrial ecosystems by altering the interaction of plants,soils,and ***,the impact of e CO_(2) on the N_(2)O emission from agricultural soils remains poorly *** meta-analysis summarizes the effect of e CO_(2) on N_(2)O emission in agricultural ecosystems and soil physiochemical and biological characteristics using 50 publications *** e CO_(2) effect values,which equal to the percentage changes of N_(2)O emission under e CO_(2),were calculated based on the natural logarithm of the response ratio to e CO_(2).We found that e CO_(2) significantly increased N_(2)O emission (by 44%),which varied depending on experimental conditions,agricultural practices,and soil *** addition,e CO_(2) significantly increased soil water-filled pore space (by 6%),dissolved organic carbon content (by11%),and nitrate nitrogen content (by 13%),but significantly reduced soil p H (by 1%).Moreover,e CO_(2) significantly increased soil microbial biomass carbon(by 28%) and soil microbial biomass nitrogen (by 7%) ***,e CO_(2) significantly increased the abundances of ammonia-oxidizing bacteria(AOB) amo A (by 21%),nir K (by 15%),and nir S (by 15%),but did not affect the abundances of ammonia-oxidizing archaea (AOA) amo A and nos *** findings indicate that e CO_(2) substantially stimulates N_(2)O emission in agroecosystems and highlight that optimization of nitrogen management and agronomic options might suppress this stimulation and aid in reducing greenhouse effect.

关键词： agricultural practices agroecosystems climate change experimental conditions greenhouse gas soil properties

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Inhibition of ammonia-oxidizing bacteria promotes the growth of ammonia-oxidizing archaea in ammonium-rich alkaline soils

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Pedosphere 2022年第4期32卷 532-542页

作者： Chang YIN Xiaoping FAN Hao CHEN Mujun YE Guochao YAN Tingqiang LI Hongyun PENG Shengzhe E Zongxian CHE Steven AWAKELIN yongchao liang Key Laboratory of Environment Remediation and Ecological Health Ministry of EducationCollege of Environmental&Resource SciencesZhejiang UniversityHangzhou 310058China Institute of Soil and Fertilizer and Water-Saving Agriculture Gansu Academy of Agricultural SciencesLanzhou 730070China Scion Research P.O.Box 29237Christchurch 8011New Zealand

Disparities in the substrate affinity and tolerance threshold for ammonia have been believed to play a key role in driving niche differentiation between ammonia-oxidizing archaea (AOA) and bacteria (AOB);however, recent surveys argue that direct competition between AOA and AOB is also important in this phenomenon. Accordingly, it is reasonable to predict that diverse AOA lineages would grow in ammonium (NH_(4)^(+))-rich alkaline arable soils if AOB growth is suppressed. To test this hypothesis, a microcosm study was established using three different types of alkaline arable soils, in which a high NH_(4)^(+) concentration (200 μg N g^(-1) dry soil) was maintained by routinely replenishing urea and the activities of AOB were selectively inhibited by 1-octyne or 3,4-dimethylpyrazole phosphate (DMPP). Compared with amendment with urea alone, 1-octyne partially retarded AOB growth, while DMPP completely inhibited AOB. Both inhibitors accelerated the growth of AOA, with significantly higher ratios of abundance of AOA to AOB observed with DMPP amendment across soils. Nonmetric multidimensional scaling analysis (NMDS) indicated that different treatments significantly altered the community structures of both AOA and AOB and AOA OTUs enriched by high-NH_(4)^(+) amendment were taxonomically constrained across the soils tested and closely related to Nitrososphaera viennensis EN76 and N. garnensis. Given that these representative strains have been demonstrated to be sensitive to high ammonia concentrations, our results suggest that it is the competitiveness for ammonia, rather than disparities in substrate affinity and tolerance threshold for ammonia, that drives niche differentiation between these phylotypes and AOB in NH_(4)^(+)-rich alkaline soils.

关键词： community structure 3,4-dimethylpyrazole phosphate niche differentiation 1-octyne substrate affinity tolerance threshold

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Effects of vacancy and external electric field on the electronic properties of the MoSi_(2)N_(4)/graphene heterostructure

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Chinese Physics B 2024年第3期33卷 542-550页

作者：梁前罗祥燕钱国林王远帆梁永超谢泉 College of Big Data and Information Engineering Institute of New Optoelectronic Materials and TechnologyGuizhou UniversityGuiyang 550025China

Recently,the newly synthesized septuple-atomic layer two-dimensional(2D)material MoSi_(2)N_(4)(MSN)has attracted attention *** work delves into the effect of vacancies and external electric fields on the electronic properties of the MSN/graphene(Gr)heterostructure using first-principles *** find that four types of defective structures,N-in,N-out,Si and Mo vacancy defects of monolayer MSN and MSN/Gr heterostructure are stable in ***,vacancy defects can effectively modulate the charge transfer at the interface of the MSN/Gr heterostructure as well as the work function of the pristine monolayer MSN and MSN/Gr ***,the application of an external electric field enables the dynamic switching between n-type and p-type Schottky *** work may offer the possibility of exceeding the capabilities of conventional Schottky diodes based on MSN/Gr heterostructures.

关键词： MoSi_(2)N_(4) vacancy defects external electric field Schottky contacts

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Evolution of defects and deformation mechanisms in different tensile directions of solidified lamellar Ti-Al alloy

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Chinese Physics B 2022年第4期31卷 518-524页

作者： Yutao Liu Tinghong Gao Yue Gao Lianxin Li Min Tan Quan Xie Qian Chen Zean Tian yongchao liang Bei Wang Institute of New Optoelectronic Materials and Technology College of Big Data and Information EngineeringGuizhou UniversityGuiyang 550025China College of Computer Science and Electronic Engineering Hunan UniversityChangsha 410082China

Two-phaseγ-TiAl/α_(2)-Ti_(3)Al lamellar intermetallics have attracted considerable attention because of their excellent strength and ***,the exact deformation mechanisms remain to be *** this paper,a solidified lamellar Ti-Al alloy with lamellar orientation at 0°,17°,and 73°with respect to the loading direction was stretched by utilizing molecular dynamics(MD)*** results show that the mechanical properties of the sample are considerably influenced by solidified defects and tensile *** structure deformation and fracture were primarily attributed to an intrinsic stacking fault(ISF)accompanied by the nucleated Shockley dislocation,and the adjacent extrinsic stacking fault(ESF)and ISF formed by solidification tend to form large HCP structures during the tensile process loading at 73°.Moreover,cleavage cracking easily occurs on theγ/α_(2)interface under tensile *** fracture loading mechanism at 17°is grain boundary slide whereas,at 73°and 0°,the dislocation piles up to form a dislocation junction.

关键词： molecular dynamics simulation solidified lamellar Ti-Al alloy tensile directions γ/α_(2)interface

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Effect of Silicon on Leaf Ultrastructure, Chlorophyll Content and Photosynthetic Activity of Barley Under Salt Stress

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Pedosphere 1998年第4期8卷 289-296页

作者： liang yongchao (Department of Plant Nutrition, College of Natural Reaources and Environmental Science, and Ministry of Agriculture Key Laboratory of Crop Growth and Regulation, Nanjing Agricultural University, Nanjing 210095 China) Department of Plant Nutrition College of Natural Resources and Environmental Science Nanjing Agricultural University Nanjing 210095 China

Two contrasting cultivars of barley (Horderm vykgare L.): Kepin No. 7 (salt sensitive), and Jian 4 (salt tolerant) were grown in a hydroponics system with 2 NaCl levels: 60 mmol NaCl L-1 and 120 mmol NaCl L-1, and 3 Si levels: 0 mmol Si L-1, 0.5 mmol Si L-1 and 1.0 mmol Si L-1 (as silicic acid). Compared with the plants treated with 60 mmol NaCl L-1 alone, the leaf chlorophyll contents of plants treated with salt and Si increased significantly for salt-sensitive cultivar at tillering stage, but for salt-tolerant cultivar,the addition of Si resulted in an obvious increase in the leaf chlorophyll content of plants exposed to 120 mmol NaCl L-1. However, this Si-enhancement of leaf chlorophyll content was also observed in the salttolerant plants at jointing stage, but not in the salt-sensitive plants. Moreover, leaf chlorophyll content was consistently higher for the salt-tolerant cultivar than for the salt-sensitive cultivar irrespective of salt and/or Si treatment. Compared with the plants treated with salt alone, net CO2 assimilation rate in plant leaves increased significantly for both cultivars when trested with salt and Si. The addition of Si to the salt treatment was found to improve the cell ultrastructure of leaves. Under salt stress condition, the double membranes of chloroplasts disappeared, but membrane integrity was markedly improved in the salt treatment supplemented with Si. Silicon was also found to ameliorate the damage to the ultrastructure of chloroplast granae which appeared to be disintegrated and vague in salt treatments without added Si. The results support previous work which showed that Si decreases the permeability of plasma membranes of salt-stressed barley, thus mitigating salt damage.

关键词： barley photosynthesis salt silicon ultrastructure

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Soil bacterial communities interact with silicon fraction transformation and promote rice yield after long-term straw return

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Soil Ecology Letters 2021年第4期3卷 395-408页

作者： Alin Song Zimin Li Yulin Liao yongchao liang Enzhao Wang Sai Wang Xu Li Jingjing Bi Zhiyuan Si Yanhong Lu Jun Nie Fenliang Fan Key Laboratory of Plant Nutrition and Fertilizer Ministry of Agriculture and Rural Affairs/Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081China Earth and Life Institute Soil SciencesUniversitécatholique de Louvain(UCLouvain)Croix du Sud 2/L7.05.101348 Louvain‐la‐NeuveBelgium Soil and Fertilizer Institute of Hunan province Hunan Academy of Agricultural SciencesChangsha 410125China Ministry of Education Key Laboratory of Environment Remediation and Ecological Health College of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China

Returning crop straw into the soil is an important practice to balance biogenic and bioavailable silicon(Si)pool in paddy,which is crucial for the healthy growth of ***,owing to little knowledge about soil microbial communities responsible for straw degradation,how straw return affects Si bioavailability,its uptake,and rice yield remains ***,we investigate the change of soil Si fractions and microbial community in a 39-year-old paddy field amended by a long-term straw *** show that rice straw return significantly increased soil bioavailable Si and rice yield from 29.9%to 61.6%and from 14.5%to 23.6%,respectively,when compared to NPK fertilization *** return significantly altered soil microbial community *** was positively and significantly related to amorphous Si,while Rokubacteria at phylum level,Deltaproteobacteria,and Holophagae at class level was negatively and significantly related to organic matter adsorbed and Fe/Mn-oxide-combined Si in *** analysis of their correlations further demonstrated that Si status significantly explained 12%of soil bacterial community *** findings suggest that soil bacteria community and diversity interact with Si mobility by altering its transformation,thus resulting in the balance of various nutrient sources to drive biological Si cycle in agroecosystem.

关键词： Bacterial community Long-term Silicon fractions Straw returning Silicon cycle

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Overexpression of proto-oncogene bcl-2 in rheumatoid synovium

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Chinese Science Bulletin 1997年第24期42卷 2087-2090页

作者： liang Haiying, WANG yongchao, CHEN Zhiqiang, CHEN Huanmian and JIANG Ming Division of Rheumatology, Peking Union Medical College Hospital, Beijing 100073, China 2. Key Laboratory of Cell Prolifer ation and Regulation Biology, Beijing Normal University, Beijing 100875, China Division of Rheumatology Peking Union Medical College Hospital Beijing 100073 China

RHEUMATOID arthritis (RA) is an autoimmune disease which progressively and systematicallyinvades the joints of bones. A severe chronic situation may lead to the damage of cartilages,bones and tendons and eventually handicap the patients. One of the main histopathological fea-tures of rheumatoid synovium is a marked increase of the thickness and the number of cells inthe synovial lining layer. It is well known that the synovial lining cells secrete many cell fac-

关键词： rheumatoid synovium synovial lining cells bcI-2 apoptosis.

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施硅对感染白粉病小麦叶片抗病相关酶活性及硅微域分布的影响

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土壤学报 2010年第3期47卷 515-522页

作者：杨艳芳梁永超安徽师范大学环境科学与工程学院安徽芜湖241003 南京农业大学资源环境学院南京210095 中国农业科学院农业资源与农业区划研究所农业部植物营养与养分循环重点实验室北京100081

以抗/感白粉病的南农99-18/苏麦3号为试验材料,研究外源硅对接种白粉病后小麦叶片的几丁质酶、β-1,3葡聚糖酶、苯丙氨酸解氨酶(PAL)、多酚氧化酶(PPO)活性和叶片硅微域分布的影响,以探讨外源硅增强小麦抗白粉病的作用机理。结果表明,... 详细信息

以抗/感白粉病的南农99-18/苏麦3号为试验材料,研究外源硅对接种白粉病后小麦叶片的几丁质酶、β-1,3葡聚糖酶、苯丙氨酸解氨酶(PAL)、多酚氧化酶(PPO)活性和叶片硅微域分布的影响,以探讨外源硅增强小麦抗白粉病的作用机理。结果表明,在不接病原菌时,施硅与否对抗/感病品种的PAL、PPO、β-1,3葡聚糖酶活性和感病品种的几丁质酶活性无显著性影响,但施硅可显著地提高抗病品种的几丁质酶活性;接种病原菌后,抗/感品种小麦叶片的几丁质酶、β-1,3葡聚糖酶、PAL和PPO活性均显著提高,而施硅处理显著地提高了感病品种的这四种酶活性和抗病品种的几丁质酶与β-1,3葡聚糖酶活性,但施硅处理对于抗病品种的PAL和PPO活性影响不显著。同时,施硅处理下,叶片硅元素相对重量都有不同程度提高,并有向刺状体基部和维管束组织富集趋势;接种病原菌后,叶片硅元素明显向病原菌侵染位点聚集,尤其有外源硅供给条件下,这种富集效应尤为显著。这意味着,硅不仅通过调节植株体内与抗病性密切相关的酶活性,而且同时可通过在侵染位点的淀积而构建了防病原菌侵入的"物理或机械屏障",以达到增强小麦的抗病性,从而抑制小麦白粉病病害发展。

关键词：硅小麦抗病相关酶白粉病

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