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Review of regional carbon counting methods for the Chinese major ecological engineering programs

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Journal of Forestry Research 2016年第4期27卷 727-738页

作者： Ji Zheng Xiaohua Wei Yuanqiu liu Guohua liu Weifeng Wang wenfei liu College of Forestry Jiangxi Agricultural UniversityNanchang 330045 China University of British Columbia (Okanagan Campus) Kelowna BC V1V1VT Canada State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesBeijing 100085 China Inner Mongolia Academy of Forestry Science Hohhot 010010 China Research Institute of Ecology & Environmental Sciences Nanchang Institute of Technology Nanchang 330099 China

In order to improve environment and relieve poverty, China has launched a series of major ecological engineering programs since the 1980 s. These include the Natural Forest Conservation Program, the Sloping Cropland Conversion Program, the Desertification Combating Program, and the Protection Forest System Construction Program. There is a growing need to quantify the contributions of these programs to regional carbon ***, the lack of widely accepted, robust methods is one of the key obstacles to quantification. The objective of this study was to review existing methods for quantifying regional carbon stocks and then recommend suitable ones for the Chinese ecological engineering programs. We expect that the recommended methods can be applied to elsewhere in the world where there are similar characteristics and objectives.

关键词： programs elsewhere vegetation contributions stocks Conversion forests obstacles biomass expect

A Two-Layer Fuzzy Control Strategy for the Participation of Energy Storage Battery Systems in Grid Frequency Regulation

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Energy Engineering 2023年第6期120卷 1445-1464页

作者： Wei Chen Na Sun Zhicheng Ma wenfei liu Haiying Dong School of New Energy and Power Engineering Lanzhou Jiaotong UniversityLanzhou730000China Electric Power Research Institute of State Grid Gansu Electric Power Company Lanzhou730070China

To address the frequency fluctuation problem caused by the power dynamic imbalance between the power system and the loadwhen a large number of newenergy sources are connected to the grid,a two-layer fuzzy control strategy is proposed for the participation of the energy storage battery system in ***,considering the coordination of FM units responding to automatic power generation control commands,a comprehensive allocation strategy of two signals under automatic power generation control commands is proposed to give full play to the advantages of two FM signals while enabling better coordination of two FM units responding to FM commands;secondly,based on the grid FM demand and battery FM capability,a double-layer fuzzy control strategy is proposed for FM units responding to automatic power generation control commands in a coordinated manner under dual-signal allocation mode to precisely allocate the power output depth of FM units,which can control the fluctuation of frequency deviation within a smaller range at a faster speed while maintaining the battery charge state;finally,the proposed Finally,the proposed control strategy is simulated and verified inMatlab/*** results show that the proposed control strategy can control the frequency deviation within a smaller range in a shorter time,better stabilize the fluctuation of the battery charge level,and improve the utilization of the FM unit.

关键词： Battery energy storage secondary FM signal distribution mode charge state two-layer fuzzy control

Responses of intra-annual runoff to forest recovery patterns in subtropical China

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Journal of Forestry Research 2021年第4期32卷 1479-1488页

作者： Zhipeng Xu wenfei liu Qiang Li Jianping Wu Honglang Duan Guomin Huang Yizao Ge Jiangxi Province Key Laboratory for Restoration of Degraded Ecosystems&Watershed Ecohydrology Nanchang Institute of TechnologyNanchang 330099People’s Republic of China Department of Civil Engineering University of Victoria3800 Finnerty RoadVictoriaBC V8P 5C2Canada Yunnan Key Laboratory of Plant Reproductive Adaption and Evolutionary Ecology Yunnan UniversityKunming 650500People’s Republic of China

Forest recovery plays a critical role in regulating eco-hydrological processes in forested ***,characteristics of the intra-annual runoff variation associated with different forest recovery patterns remain poorly *** this study,three forest change periods were identified,the baseline period(1961-1985),reforestation period(1986-2000)and fruit tree planting period(2001-2016).We selected the magnitude of seasonal runoff(wet and dry seasons)and distribution characteristics,i.e.,non-uniformity coefficient(C_(v)),complete accommodation coefficient(C_(r)),concentration ratio(C_(n)),concentration period(C_(d)),absolute variation ratio(ΔR)and relative variation ratio(C_(max)).The pair-wise approach evaluated the intra-annual runoff variation characteristics between forest change *** indicate that reforestation decreased wet season runoff and increased dry season *** contrast,fruit tree planting increased wet season runoff and had no significant effect on dry season *** intra-annual runoff distribution characteristics,reforestation significantly reduced the C_(v),C_(r),C_(n)and C_(max).Distribution of the intra-annual runoff in the fruit tree planting period was not significantly different from the *** concluded that reforestation reduced the occurance of extreme water conditions in wet and dry seasons and effectively increased the stability of the intra-annual *** contrast,fruit tree planting increased instability and fluctuation of the intra-annual runoff after *** characteristics of the intra-annual runoff to fruit tree planting was similar to those of the ***,adopting fruit tree planting practices to regulate intra-annual runoff characteristics may not be a practical approach,and impacts of different reforestation practices should be ascertained in our study *** implications of this study should guide regional land-water management,and this study adds to the understanding o

关键词： Intra-annual runoff variation Seasonal runoff Forest recovery Reforestation Fruit tree planting

Linkages among leaf nutrient concentration,resorption efficiency, litter decomposition and their stoichiometry to canopy nitrogen addition and understory removal in subtropical plantation

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Ecological Processes 2024年第2期13卷 90-102页

作者： Jawad Ali Shah wenfei liu Saif Ullah Honglang Duan Fangfang Shen Yingchun Liao Guomin Huang Jianping Wu Ministry of Education Key Laboratory for Transboundary Ecosecurity of Southwest China Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology and Institute of Biodiversity School of Ecology and Environmental Science Yunnan University Laboratory of Soil Ecology and Health in Universities of Yunnan Province Yunnan University Jiangxi Key Laboratory for Restoration of Degraded Ecosystems & Watershed Ecohydrology Nanchang Institute of Technology Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou Province Institute for Forest Resources and Environment of Guizhou College of ForestryGuizhou University

Background The prevalence of understory removal and anthropogenic nitrogen(N) deposition has significantly altered the ecological processes of forest ecosystems at both regional and global scales. However, it remains a pressing challenge to understand how N deposition and understory removal affect leaf nutrient dynamics, nutrient resorption, litter decomposition, and their linkages for better managing forest ecosystems under nutrient imbalances induced by N enrichment. To address this research gap, a field manipulation experiment was carried out in a subtropical Cunninghamia lanceolata plantation with four treatments including: control(CK), canopy N addition(CN), understory removal(UR), and canopy N addition plus understory removal(CN × UR). Green and senesced leaf N and phosphorus(P) concentrations, N and P resorption efficiencies, litter decomposition, and their correlations were *** The results revealed that the average N concentrations of green early and late leaves in UR were increased by 6.61 and 18.89% compared to CK. UR had the highest whereas CN had the lowest P concentrations in green leaves across the two sampling seasons. Following this, UR, leaf type, season, and their interactions significantly affected leaf N, P, and N:P(P < 0.05). The highest leaf N resorption(32.68%) and P resorption efficiencies(63.96%) were recorded in UR. Litter decomposition was significantly retarded in UR(P < 0.01) relative to CN. The regression analysis demonstrated that leaf nutrient status was significantly interconnected with leaf nutrient resorption efficiencies. In addition, leaf nutrient dynamics were strongly correlated with litter nutrients, indicating that both were *** These findings can deepen our knowledge of biogeochemical cycling and reveal contrasting nutrientacquisition strategies on N and P limitation in response to UR and CN. Considering the P limitation, it is important to note that P was resorbed more efficiently, illustrating a

关键词： Nutrient resorption Nitrogen deposition Litter decomposition Stoichiometry Understory removal Subtropical plantation

The decoupling between gas exchange and water potential of Cinnamomum camphora seedlings during drought recovery and its relation to ABA accumulation in leaves

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Journal of Plant Ecology 2020年第6期13卷 683-692页

作者： Honglang Duan Defu Wang Xiaohua Wei Guomin Huang Houbao Fan Shuangxi Zhou Jianping Wu wenfei liu David TTissue Songze Wan Institute for Forest Resources&Environment of Guizhou Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou ProvinceCollege of ForestryGuizhou UniversityGuiyang 550025China Jiangxi Provincial Key Laboratory for Restoration of Degraded Ecosystems&Watershed Ecohydrology Nanchang Institute of TechnologyNanchang 330099China Department of Earth Environmental and Geographic SciencesUniversity of British Columbia OkanaganKelownaBC V1V 1V7Canada The New Zealand Institute for Plant and Food Research Ltd. Hawke’s BayNew Zealand Laboratory of Ecology and Evolutionary Biology Yunnan UniversityKunming 650500China Hawkesbury Institute for the Environment Hawkesbury CampusWestern Sydney UniversityLocked Bag 1797PenrithNSW 2751Australia College of Forestry Jiangxi Agricultural UniversityNanchang 330045China

Aims Drought stress and the degree of drought severity are predicted to rise under highly variable patterns of precipitation due to climate change,while the capacity of trees to cope with drought recovery through physiological and biochemical adjustment remains *** aimed to examine the coupling of physiology and biochemistry in trees during drought and the following *** Potted seedlings of Cinnamomum camphora were grown under well watered conditions prior to the experimental drought stress,which was initiated by withholding *** were rewatered following attainment of two drought severities:mild drought(stomatal closure)and moderate drought(ψxylem=−1.5 MPa).We measured leaf-level water potential,gas exchange(photosynthesis and stomatal conductance),abscisic acid(ABA),proline and non-structural carbohydrates(NSCs)concentrations in seedlings of *** during drought and a 4-day *** Findings We found that drought severity largely determined physiological and biochemical responses and affected the rate of *** closure occurred at the mild drought stress,accompanied with ABA accumulation in leaves and decline in water potential,while leaf proline accumulation and variable NSC were evident at the moderate drought *** severe drought stress led to delayed recovery of gas exchange,but it did not have significant effect on water potential *** relationships of water potential and gas exchange differed during drought stress and post-drought *** was tight coupling between water potential and gas exchange during drought,but not during rewatering due to high ABA accumulation in leaves,thereby delaying recovery of stomatal *** results demonstrate that ABA could be an important factor in delaying the recovery of stomatal conductance following rewatering and after water potential recovery of ***,greater drought severity had significant impacts on the rate of recove

关键词： drought recovery gas exchange ABA NSC proline

Hemagglutinin stem reactive antibody response in individuals immunized with a seasonal influenza trivalent vaccine

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Protein & Cell 2015年第6期6卷 453-457页

作者： Xiaopeng Zhao Kun Qin Jinlei Guo Donghong Wang Zi Li wenfei Zhu Liqi liu Dayan Wang Yuelong Shu Jianfang Zhou National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention Key Laboratory for Medical Virology National Health and Family Planning Commission Beijing 102206 China

Dear Editor, Influenza is a contagious, acute respiratory disease caused by influenza viruses. Type A influenza virus has a broad host range and has caused substantial human morbidity and mortality. There are sixteen subtypes of influenza A virus so far, which are divided into two distinct groups： group 1 （H1, H2, H5, H6, H8, H9, Hll, H12, H13 and H16） and group 2 （H3, H4, H7, H10, H14 and H15）（Corti et al., 2011）. Seasonal H1 and H3 subtype influenza viruses are circulating in the human population.

关键词： Hemagglutinin stem antibody response trivalent vaccine

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陀思妥耶夫斯基的虚构和非虚构写作

外国文学 2022年第4期 3-12页

作者：刘文飞首都师范大学外国语学院北京100089

陀思妥耶夫斯基的写作由虚构和非虚构两大板块构成,这两大板块在他的创作中各占半壁江山。陀思妥耶夫斯基的虚构和非虚构写作均服务于同一目的,即阐释作家的俄罗斯理念。陀思妥耶夫斯基同时进行虚构和非虚构写作,既受当时俄国社会和文... 详细信息

陀思妥耶夫斯基的写作由虚构和非虚构两大板块构成,这两大板块在他的创作中各占半壁江山。陀思妥耶夫斯基的虚构和非虚构写作均服务于同一目的,即阐释作家的俄罗斯理念。陀思妥耶夫斯基同时进行虚构和非虚构写作,既受当时俄国社会和文化语境的左右,也是他独特的叙事策略之结果。陀思妥耶夫斯基晚年的几个短篇小说,显示出他在虚构和非虚构之间腾挪转移的独特的小说叙事手法。同时关注陀思妥耶夫斯基的虚构和非虚构写作,能使我们更全面、更完整地认识和理解陀思妥耶夫斯基这位思想家作家及其多元创作。

关键词：陀思妥耶夫斯基虚构非虚构思想小说

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CFRP平-折-平胶接接头应力模型

哈尔滨工业大学学报 2020年第7期52卷 139-146页

作者：许昶刘志明刘文飞北京交通大学机械与电子控制工程学院北京100044 台州学院航空工程学院浙江台州317000

以碳纤维增强双马来酰亚胺树脂基复合材料平-折-平(FJF)胶接连接接头为对象,构造了圆弧段胶接梁单元,建立用于FJF胶接接头胶层应力分析的半解析模型,并与三维有限元模型胶层应力结果进行对比.同时分析了胶层宽度和厚度对胶层应力的影响... 详细信息

以碳纤维增强双马来酰亚胺树脂基复合材料平-折-平(FJF)胶接连接接头为对象,构造了圆弧段胶接梁单元,建立用于FJF胶接接头胶层应力分析的半解析模型,并与三维有限元模型胶层应力结果进行对比.同时分析了胶层宽度和厚度对胶层应力的影响.结果表明,利用半解析模型计算得出的胶层剥离应力和剪切应力分布与三维有限元模型获得的对应应力分布基本一致,搭接区端部胶层剥离应力和剪切应力相较于三维有限元模型计算结果的误差绝对值分别为5.4%和3.7%,有着较好的计算精度.搭接区端部胶层剥离应力和剪切应力值在胶层宽度一定时随胶层厚度的增加而降低,在胶层厚度一定时随胶层宽度的增加而降低.搭接区圆角胶层剥离应力和剪切应力值在胶层厚度一定时随胶层宽度的增加而降低,在胶层宽度一定时随胶层厚度的增加而增加.该模型能够为碳纤维增强复合材料平-折-平胶接连接接头的应力分析提供一定的参考.

关键词：碳纤维增强复合材料 FJF胶接连接接头半解析模型胶层应力分析胶层宽度胶层厚度

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苏联解体后俄国文学的若干悖论走向

文学评论 2021年第4期 95-103页

作者：刘文飞首都师范大学外国语学院

苏联解体至今的俄国文学在近30年间显示出若干充满悖论的新走向,如文学的非意识形态化进程之后东正教思想对文学的渗透,文学中心主义逐渐消解之后生发的新的文学造神运动,后现代主义文学狂欢之后新现实主义、后现实主义和新现代主义的... 详细信息

苏联解体至今的俄国文学在近30年间显示出若干充满悖论的新走向,如文学的非意识形态化进程之后东正教思想对文学的渗透,文学中心主义逐渐消解之后生发的新的文学造神运动,后现代主义文学狂欢之后新现实主义、后现实主义和新现代主义的此起彼伏,以及女性文学崛起后的文学性别的中性化、经典文学的大众化和大众文学的经典化、斯拉夫派和西方派的思想对峙及其此消彼长等。这些悖论走向表明,俄国当代文学经历了复杂甚或艰难的发展过程,俄国当代作家和文艺学家们始终在进行紧张的创作实验和理论探索,与此同时,这些悖论走向也从另一侧面论证了俄国文学自身保有的张力和活力,预示着其未来发展的潜能和动能。

关键词：俄国文学文学中心主义后现代主义新现实主义后现实主义新现代主义