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Effects of global change and human disturbance on soil carbon cycling in boreal forest: A review

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Pedosphere 2023年第1期33卷 194-211页

作者： Pengshuai SHAO Hongyan HAN Jingkuan SUN Hongtu XIE Shandong Key Laboratory of Eco-environmental Science for the Yellow River Delta Binzhou UniversityBinzhou 256603China Institute of Applied Ecology Chinese Academy of SciencesShenyang 110016China

Increasing human demands for Earth’s resources are hastening many environmental changes and creating a need to incorporate the routine monitoring of ecosystem functions into forest *** global change and anthropogenic disturbances,soil carbon(C)cycling in terrestrial ecosystems is undergoing substantial changes that result in the transformation between soil C sources and ***,the forest C budget requires an understanding of the underlying soil C dynamic under environmental *** present review focuses on the response and feedback of soil C cycling to global change(climate warming and nitrogen(N)deposition)and human disturbances(fire and logging)and detects the association of soil C cycling with soil C and N efflux and inflow in boreal *** effects of climate warming and N deposition on soil C cycling are complex,especially at short-term temporal *** warming can decay soil organic matter(SOM)to emit substantial amounts of CO2,and differing warming durations result in different effects on soil C loss,ranging from ca.1 to 15 Mg C ha−***-term soil warming mainly reduces the labile soil C pool and increases the decomposition of recalcitrant soil C compounds(e.g.,lignin),whereas longer-term warming may limit soil C loss due to impoverished soil C substrate and microbial *** N addition is conducive to enhancing soil C storage(ca.2–22 Mg C ha−1),by increasing plant productivity including above-and belowground biomass;however,chronic N deposition or excess N addition can result in soil acidity,reducing N use efficiency and plant growth and further resulting in no changes or declines in soil C *** and logging lead to a large quantity of soil C loss via impaired plant productivity and increased organic matter degradation,exacerbating global *** particular,severe fire can cause a large amount of soil C loss,ca.16–34 Mg C ha−1 in the data we ***,the black C input induced by fire

关键词： climate warming forest C budget forest management N deposition soil microorganism terrestrial ecosystem

THE QUEUE-LENGTH DISTRIBUTION FOR M^x/G/1 QUEUE WITH SINGLE SERVER VACATION

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Acta Mathematica Scientia 2000年第3期20卷 397-408页

作者：唐应辉唐小我 Department of Applied Mathematics Management College Univerisity of Electronic Science & Technology of China Chengdu 610054 China

This paper studies the bulk-arrival M-x/G/1 queue with single server vacation. By introducing the server busy period and using the Laplace transform, the recursion expression of the Laplace transform of the transient queue-length distribution is derived. Furthermore, the distribution and stochastic decomposition result of the queue length at a random point in equilibrium are obtained. Especially some results for the single-arrival M/G/1 queue with single server vacation and bulk-arrival M-x/G/1 queue but with no server vacation can be derived directly by the results obtained in this paper.

关键词： server vacation queue length transient distribution equilibrium distribution stochastic decomposition

Development of the Self-doping Porous Carbon and Its Application in Supercapacitor Electrode

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Chemical Research in Chinese Universities 2022年第4期38卷 1065-1072页

作者： YANG Zhichen KANG Xiaoting ZOU Bo YUAN Xuna LI Yajie WU Qin GUO Yupeng college of Chemistry Jilin UniversityChangchun130012P.R.China

The massive discharge of biomass wastes not only causes waste of resources,but also pollutes the ***,converting biomass wastes into carbon materials is an effective way to solve the above ***,using biomass waste pig nails as raw materials and K_(2)CO_(3) as chemical activators,the N-doped porous carbon(KPNC)is prepared by direct *** an electrode for supercapacitors,the electrochemical tests of KPNCs showed that they exhibited good electrochemical performance and excellent cycling *** the current density is 0.2 A/g,the specific capacitance is up to 344.6 F/***,it still maintains 97.6%initial capacitance retention after 2000 cycles at a high current density of 5 A/*** exceptional electrochemical performances may be ascribed to an appropriate porous structure(Smicro/Stotal=80.31%,Vmicro/Vtotal=76.19%),high nitrogen contents(4.44%,atomic fraction),oxygen contents(9.13%,atomic fraction)as well as small internal *** above experimental results show that the conversion of pig nails to porous carbon can reduce the waste of resources and alleviate environmental pollution.

关键词： Supercapacitor Porous carbon Biomass waste Heteroatom doping Electrochemical performance

Seed nutrient is more stable than leaf in response to changing multiple resources in an alpine meadow

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Ecological Processes 2023年第3期12卷 153-161页

作者： Jiapu Li Dashuan Tian Kailiang Yu Hongbo Guo Ruiyang Zhang Jinsong Wang Qingping Zhou Shuli Niu Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences college of Resources and environmental Sciences Nanjing Agricultural University college of Resources and Environment University of Chinese Academy of Sciences High Meadows environmental Institute Princeton University Institute of Qinghai-Tibetan Plateau Southwest Minzu University

Background It has been long thought that nitrogen(N), phosphorus(P) concentrations and their ratios(N:P) in metabolically active or functional organs(i.e., leaves) are less responsive to environmental changes. Little attention, however, has been paid to the reproductive organs—seeds, while seeds may maintain their nutrients more stable for the evolutionary fitness of next *** Here, we conducted a field experiment of N, P addition and drought in an alpine meadow, aiming to compare the difference of leaf and seed nutrients and stoichiometric ratios in response to these resource treatments and their interactions. Four dominant species were selected among grass and forb functional groups, including Elymus nutans, Deschampsia caespitosa, Artemisia roxburghiana and Polygonum *** Under natural conditions, leaf N and P concentrations were consistently lower than seed among species. However, leaf nutrients were much more sensitive than seed nutrients to N and P addition. Specifically, N or P addition accordingly increased leaf N or P concentration by 22.20–44.24% and 85.54–93.61%, while only enhanced seed N or P concentration by 5.15–17.20% and 15.17–32.72%, respectively. Leaf N or P concentration was significantly reduced by P or N addition, but seed nutrients remained unchanged. In contrast, drought did not change both organ nutrients. Similarly, nutrient addition and drought had synergistic interactions on leaf nutrients, but not on seed *** This study highlights that seed nutrient concentrations could be more stable than metabolically active leaf organ when facing multidimensional resource changes. This complements the traditional view on the 'Stable Leaf Nutrient Hypothesis' with the involvement of reproductive organs. The less responsiveness of seed nutrients suggests the adaptive strategy to ensure the success of next generations and long-term plant demographic stability.

关键词： Alpine meadow Leaf Multiple resource change Nitrogen concentration N:P ratio Phosphorus concentrations Seed

Influence of Oxygen-Containing Functional Groups on Asphaltene Self-Diffusion Coefficient in Asphaltene-Xylene Systems

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china Petroleum Processing & Petrochemical Technology 2022年第2期24卷 118-125页

作者： Yang Haiyang Wang Chunlu Ren Qiang Wang Lixin Yan Xuemin college of Chemistry&environmental Engineering Yangtze UniversityJingzhou 434023 SINOPEC Research Institute of Petroleum Processing Beijing 100083

Molecular simulations were carried out to investigate the self-diffusion coefficient of asphaltene in asphaltene-xylene systems,used as heavy oil *** self-diffusion behavior of asphaltene in the asphaltene-xylene equilibrium system was mainly affected by the interaction between asphaltene molecules,with stronger interactions corresponding to a slower diffusion of *** interactions between asphaltene molecules mainly includedπ-πinteractions between aromatic rings and hydrogen bonds between strongly electronegative *** results are expected to provide theoretical guidance for reducing the viscosity of heavy oil.

关键词： heavy oil asphaltenes viscous mechanism molecular simulation molecular dynamics

AGRICULTURAL GREEN DEVELOPMENT TO ACHIEVE FOOD SECURITY AND CARBON REDUCTION IN THE CONTEXT OF china'S DUAL CARBON GOALS

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Frontiers of Agricultural Science and Engineering 2023年第2期10卷 262-267页

作者： Yulong YIN Kai HE Zhong CHEN Yangyang LI Fengling REN Zihan WANG Yingcheng WANG Haiqing GONG Qichao ZHU Jianbo SHEN Xuejun LIU Zhenling CUI college of Resources and environmental Sciences National Academy of Agriculture Green DevelopmentKey Laboratory of Plant-Soil Interactions(Ministry of Education)Key Laboratory of Low-carbon Green Agriculture(Ministry of Agriculture and Rural Affairs)China Agricultural UniversityBeijing 100193China

The agricultural sector,a major source of greenhouse gas emissions,and emissions from agriculture must be reduced substantially to achieve carbon(C)*** on a literature analysis and other research results,this study investigated the effects and prospects of C reduction in agricultural systems under different scenarios(i.e.,methods and approaches)in the context of china's dual C goals,as those working in the agricultural sector have yet to reach a consensus on how to move *** views,standards,and countermeasures were analyzed to provide a reference for agricultural action supporting china's C neutrality goal.

关键词： agriculture carbon neutrality carbon peak food security carbon mitigation strategies

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碳中和愿景下中国可持续农田土壤修复路径

Engineering 2023年第6期25卷 28-31页

作者：李芳柏方利平吴丰昌 National–Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South china Guangdong Key Laboratory of Integrated Agro-Environmental Pollution Control and ManagementInstitute of Eco-Environmental and Soil SciencesGuangdong Academy of SciencesGuangzhou 510650China State Key Laboratory of environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China

*** Agricultural soil pollution is a major threat affecting soil health and the ability of soil to yield safe and sufficient food;thus,it is a barrier to the goal of zero hunger worldwide[1].The food deficiency proble... 详细信息

关键词： soil pollution Agricultural

Response of ammonia-oxidizing archaea to heavy metal contamination in freshwater sediment

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Journal of environmental Sciences 2019年第3期31卷 392-399页

作者： Ningning Li Yao Chen Zhengke Zhang Sha Chang Dawei Huang Sili Chen Qingwei Guo Shuguang Xie Yongxin Bing State Key Joint Laboratory of environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University South china Institute of environmental Sciences (SCIES) Ministry of Environment Protection (MEP)

It has been well-documented that the distribution of ammonia-oxidizing bacteria(AOB) and archaea(AOA) in soils can be affected by heavy metal contamination, whereas information about the impact of heavy metal on these ammonia-oxidizing microorganisms in freshwater sediment is still lacking. The present study explored the change of sediment ammonia-oxidizing microorganisms in a freshwater reservoir after being accidentally contaminated by industrial discharge containing high levels of metals. Bacterial amoA gene was found to be below the quantitative PCR detection and was not successfully amplified by conventional PCR. The number of archaeal amoA gene in reservoir sediments were 9.62 × 10~2–1.35 × 10~7 copies per gram dry sediment. AOA abundance continuously decreased, and AOA richness, diversity and community structure also considerably varied with time. Therefore, heavy metal pollution could have a profound impact on freshwater sediment AOA community. This work could expand our knowledge of the effect of heavy metal contamination on nitrification in natural ecosystems.

关键词： Ammonia-oxidizing archaea Freshwater sediment Heavy metal Nitrosopumilus

The Activity of AQP9 Is Mediated MAPK in Arsenic-Treated Mouse Model of Hepatocellular Carcinoma

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Advances in Bioscience and Biotechnology 2022年第12期13卷 545-553页

作者： Qianqian Wang Ping Wang Xiaozhen Wang Xiaowen Wang Zeyan Zhang Fuzhi Lian Rong Zhen Yifei Cao college of Medicine and Health management Hangzhou Normal University Hangzhou China

Background: Arsenic metabolism is primarily undergoing in hepatocytes, but the underlying mechanisms are to be defined. It is essential to study the response of aquaporin AQP9, protein kinase p38, and JNK with the stimulation of arsenic in mouse models of hepatocellular carcinoma. Methods: Mouse model of hepatocellular carcinoma (HCC) was induced with H22 cells injected subcutaneously on the lateral side of each right axilla in C57BL/6 mice. Then, western blotting and co-immunoprecipitation were used to detect the protein expression and phosphorylation of molecules AQP9, p38 and JNK in mouse models of hepatocellular carcinoma, respectively. The hepatocellular distribution of AQP9 was examined by the immunofluorescent method. Results: In both wild mice and a mouse model of liver tumor, there was no significant difference in the expressions of AQP9, protein kinase p38, and JNK after arsenic treatment, but the phosphorylation expression levels of the three were significantly increased to varying degrees, and the tumor model Compared with the wild-type group, the expression increased. Laser confocal experiments showed that in HepG2 cells, phosphorylated AQP9 was mainly distributed on the cell membrane under the stimulation of arsenic. Conclusion: Arsenic stimulation can increase the phosphorylation of AQP9, p38, and JNK in both wild-type C57 mice and liver tumor mice models. Arsenic stimulation facilitates phosphorylated-AQP9 predominantly distributed on the cell membrane of hepatoma cells HepG2.

关键词： AQP9 Phosphorylation P38 JNK Arsenic