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Heavy metal accumulation characteristics and physiological response of Sabina chinensis and Platycladus orientalis to atmospheric pollution

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Journal of Environmental Sciences 2022年第2期34卷 192-201页

作者： Ning Cui laiye qu Gang Wu State Key Laboratory of Urban and Regional Ecology Research Center for Eco-environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Heavy metal(Cu,Mn,Zn,Pb,and Cd)concentrations were measured in the leaves of Sabina chinensis and Platycladus orientalis collected from urban,suburban,and rural sites in Tianjin,China.Photosynthetic pigment contents,reactive oxygen species content,malondialdehyde(MDA)content and antioxidant enzyme activity were investigated,providing physiological response parameters.Our comparison of the sites revealed that urbanization significantly influenced the heavy metal concentrations in both plant leaves.At the rural site,both plant leaves exhibited the lowest heavy metal accumulation.The highest Cu,Mn,and Zn concentrations were found in S.chinensis leaves from the urban site;the highest Pb and Cd concentrations were found in P.orientalis leaves from the urban site.These results indicate that the urban site contained larger heavy metal concentrations in the plant leaves that may reflect the anthropogenic emission gradient.It is also found that S.chinensis may be used to monitor airborne heavy metal pollution because it is highly quick response to heavy metals,while P.orientalis may be used for mitigation due to its high resistance.The results of this study can contribute to the development of monitoring and environmental management plans by providing information on sensitive and resistant tree species for city greening in North China.

关键词： Atmospheric heavy metal pollutions Sabina chinensis Platycladus orientalis Physiological responses

Effects of road dust on the growth characteristics of Sophora japonica L.seedlings

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Journal of Environmental Sciences 2016年第8期28卷 147-155页

作者： Le Bao laiye qu Keming Ma Lin Lin State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences University of Chinese Academy of Science

Road dust is one of the most common pollutants and causes a series of negative effects on plant physiology. Dust＇s impacts on plants can be regarded as a combination of load,composition and grain size impacts on plants; however, there is a lack of integrated dust effect studies involving these three aspects. In our study, Sophora japonica seedlings were artificially dusted with road dust collected from the road surface of Beijing so that we could study the impacts of this dust on nitrogen/carbon allocation, biomass allocation and photosynthetic pigments from the three aspects of composition, load and grain size. The results showed that the growth characteristics of S. japonica seedlings were mostly influenced by dust composition and load. Leaf N, root–shoot ratio and chlorophyll a/b were significantly affected by dust composition and load; leaf C/N, shoot biomass, total chlorophyll and carotenoid were significantly affected by dust load; stem N and stem C/N were significantly affected by dust composition; while the dust grain size alone did not affect any of the growth characteristics. Road dust did influence the growth characteristics more extensively than loam. Therefore, a higher dust load could increase the differences between road dust and loam treatments. The elements in dust are well correlated to the shoot N, shoot C/N, and root–shoot ratio of S. japonica seedlings. This knowledge could benefit the management of urban green spaces.

关键词： Dust composition Dust load Dust grain size Nitrogen Biomass

Impacts of regional land-use patterns on ecosystem services in the typical agro-pastoral ecotone of northern China

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Ecosystem Health and Sustainability 2022年第1期8卷 534-553页

作者： Huimin Chen Yu Zhao Xiao Fu Mingfang Tang Mingjie Guo Shiqi Zhang Yu Zhu laiye qu Gang Wu State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina China IPPR International Engineering Co. LtdBeijingChina

A comprehensive understanding of the spatial-temporal evolution and driving forces on ecosystem services(ES)is essential for the agro-pastoral ecotone’s ecological security in northern China.However,the land-use pattern(LULC)agglomeration with spatial differentiation in the pastoral and agricultural areas has been rarely concerned.Taking distinct LULC(1980-2018)in Chifeng as an example,we compared four crucial categories of ESs with InVEST.Using SEM,we further contrasted the effects of several variables on regional ES variations in pastoral-dominated(North)and agriculture-dominated(South)regions,respectively.Results revealed the conversion between forest and grassland oriented the LULC transformation in the North.In contrast,human-activitiy-oriented land tended to occupy environmentally sensitive places in the South.Similar ES variations were supplied with the North outperforming the South when soil conservation was omitted.As for the impacts of regional ES variations,the natural and LULC policies both showed positive effects,whereas the anthropogenic factors showed positive in the North,which was negative in the South.Therefore,the ecologicallymaintained-dominant and ecologically-restored-dominant strategies should be separately adopted in the North and South.Our study provided appropriate regional ecological management suggestions for balancing the LULC-driven conflicts between ecological protection and regional development.

关键词： Distinct land use/land cover(LULC)patterns Spatialtemporal evolution of ecosystem services(ESs) Agro-pastoral ecotone of northern China InVEST models Structural equation modeling(SEM)

Effects of plant coverage on shrub fertile islands in the Upper Minjiang River Valley

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Science China(Life Sciences) 2018年第3期61卷 340-347页

作者： laiye qu Zhongbin Wang Yuanyuan Huang Yuxin Zhang Chengjun Song Keming Ma State Key Laboratory of Urban and Regional Ecology Research Center for Eco-environmental Science Chinese Academy of SciencesBeijing 100085 China University of Chinese Academy of Sciences Beijing 100049 China Department of Microbiology and Plant Biology University of Oklahoma Norman 73019 USA Institute of Energy and Environmental Protection Chinese Academy of Agriculture Engineering Beijing 100125 China

The patchy distribution of vegetation in dry land results in well-documented "fertile islands". However, the response of shrub fertile islands to plant recovery and the underlying mechanisms, such as the linkage plant and soil properties, remain unknown.We sampled soils from areas with three different plant coverages(25%, 45%, and 75%) and three of their adjacent inter-plants to investigate soil physicochemical and microbial properties in the upper Minjiang River arid valley. The results showed that these factors were influenced by the persistence of plants that contrasted with the inter-plant interspaces. We found fertile islands in under-plant soil that were enhanced with increasing plant coverage, from 25% to 45% and 75%; however, there were no significant differences between 45% and 75% plant coverage apart from the soil clay content and the fungi to bacteria ratio. The soil microbial communities in under-plant soil were strongly influenced by the total soil carbon(TC), soil organic carbon(SOC),and available nitrogen(AN), whereas the microbial communities in inter-plant soil were primarily constrained by the AN and available phosphorous(AP). Moreover, the inter-plant soil properties, including gravimetric soil water content, pH, electrical conductivity(EC), and soil C:N ratio, were also strongly influenced by adjacent vegetation, which suggested that fertile islands may be beneficial for plant recovery in this region.

关键词：植物恢复灌木山谷土壤性质微生物物理化学土壤碳土壤水

Time-Periodic Solutions to quasilinear Hyperbolic Systems on General Networks

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Chinese Annals of Mathematics,Series B 2024年第1期45卷 41-72页

作者： Peng qu School of Mathematical Sciences Fudan UniversityShanghai 200433China

For quasilinear hyperbolic systems on general networks with time-periodic boundary-interface conditions with a dissipative structure,the existence and stability of the time-periodic classical solutions are discussed.

关键词： Time-periodic solution quasilinear hyperbolic system General net-work Classical solution Asymptotic stability

Flat jet electrochemical milling of TC4 alloy with tailoring backward parallel flow

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Chinese Journal of Aeronautics 2024年第4期37卷 574-592页

作者： Huanghai KONG Ningsong qu College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

In flat jet electrochemical milling, the electrolyte forms a backward parallel flow after impacting the workpiece, resulting in a weak current density distribution on the workpiece. Poor surface quality usually occurs on the machined titanium alloy surface because it inevitably suffers from the weak current density. In this study, a method of flat jet electrochemical milling with tailoring the backward parallel flow was proposed to eliminate the negative effects caused by the weak current density. Multiphysics simulations are carried out to comprehend the mechanism of flat jetEC milling with tailoring backward parallel flow and better construct the novel tool electrode.Experiments on flat jet electrochemical milling of TC4 alloy with and without tailoring backward parallel flow are conducted. The results reveal that, compared with flat jet electrochemical milling without tailoring backward parallel flow, the recommended tool reduces the surface roughness by86% to 93%, and improves the material removal rate by 93% to 163% with different feed rates.Additionally, the recommended tool is more conducive to maintaining the inherent hardness of the material. Finally, a surface with low Sa of 0.37 μm is obtained.

关键词： Flat jet electrochemical milling TC4 alloy Surface roughness Micro-hardness Material removal rate

Pathways toward a pollution-free planet and challenges

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Frontiers of Environmental Science & Engineering 2024年第6期18卷 3-8页

作者： Jiuhui qu Jiaping Chen School of Environment Tsinghua UniversityBeijing 100084China College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

The mission of“Establishment of Zero-Pollution Earth”defined by United Nations Environment Programme aims at creation of a clean,safe and prosperous home for all human beings.It is of rational choice from each individual to protect our environment and demonstrates our great ambition to achieve our goals.The key message given in this article is that,zero pollution does not mean no discharge of pollutants and instead it can be achievable through optimizing and controlling a sound balance between pollutants discharge and capacities of decontamination through treatment and natural environmental accumulation,which can be termed as“Principle of Equilibrium”between pollution and decontamination.Based on this principle,we propose and illustrate several key factors and synergistic pathways toward a pollution-free planet:quantitative determination on purification and wastewater;source control through green measures;minimization of negative side-effects;precise management through digitalized systems;and keeping sound balance between pollutants and natural purification.It should be noted that we would face a series of difficulties and challenges in moving forward to“Zero-Pollution Earth”.We should further develop theories,principles and tools to achieve the balance between quantity of pollutants and decontamination capacities.Environmentalists should work together to break through the bottleneck limited by“Principle of equilibrium”to establish new environmental remediation systems leading to“Zero-Pollution Earth”.

关键词： Wastewater treatment Resources Recovery Greenhouse gases Energy Pollution-free

通辽露天煤矿排土场恢复初期土壤碳组分变化及影响因素

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环境工程学报 2023年第10期17卷 3400-3407页

作者：杨漫朱月徐长友刘永杰曾利学曲来叶牡丹江师范学院生命科学与技术学院牡丹江157011 国家电投集团内蒙古能源有限公司通辽028000 中国科学院生态环境研究中心城市与区域生态国家重点实验室北京100085

通过研究露天煤矿排土场植被恢复初期土壤碳的变化规律及相关的影响因素,可为矿区排土场生态恢复提供科学依据和决策支持。为此,以内蒙古通辽高寒露天煤矿排土场土壤为研究对象,分别在2018、2019和2020年植物复垦土壤以及2021年未复垦... 详细信息

通过研究露天煤矿排土场植被恢复初期土壤碳的变化规律及相关的影响因素,可为矿区排土场生态恢复提供科学依据和决策支持。为此,以内蒙古通辽高寒露天煤矿排土场土壤为研究对象,分别在2018、2019和2020年植物复垦土壤以及2021年未复垦土壤进行调查取样,探究了恢复初期土壤全碳、有机质、颗粒有机碳(POC)、矿物结合态有机物(MAOC)和土壤微生物量碳(MBC)变化规律及影响因素。结果表明:植被复垦后土壤碳组分显著高于对照土壤,并随着排土场植被恢复时间的增加,土壤活性有机质中的POC、MAOC组分以及MBC的含量显著增加,但土壤全碳含量的差异不显著。土壤pH显著影响土壤全碳和MAOC含量,而土壤铵态氮与土壤碳累积呈负相关。随着植被恢复时间的增加,土壤pH降低,并与土壤全碳和MAOC的含量显著增加显著相关。因此,植被恢复对于排土场土壤碳累积具有重要的意义,同时在排土场生态恢复的过程中应重视土壤盐碱化治理。

关键词：露天煤矿恢复年限土壤碳组分

Physiological and psychological responses to tended plant communities with varying color characteristics

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Journal of Forestry Research 2024年第1期35卷 183-201页

作者： Siyuan Zheng Yanzhen Zhou Haiyan qu School of Architecture and Urban Planning Shenyang Jianzhu UniversityShenyang 110168People’s Republic of China

Exposure to plants has been reported to promote health and reduce stress,and plant color has direct impacts on physical and mental health.We used images of common types of tended plant communities in Shenyang,China,with combinations of yellow,green,and red foliage,as experimental stimuli.A total of 27 images were used as visual stimuli.We used electroencephalography to measureαwave activity(8-13 Hz)in 40 subjects while they viewed visual stimuli.These data were combined with subjective questionnaire data to analyze the relaxing effect of images of tended plant communities with different color types and proportions on people.The results revealed that,although there were slight differences between the electroencephalography and psychological findings,women were significantly more relaxed than men after viewing the images.Physiological and psychological responses varied with the types and proportions of colors in the tended plant communities:those of foliage with combinations of two or three colors induced stronger responses than images with a single color.Specifically,(1)for one-color plant communities,green or yellow plant communities induced a stronger relaxation effect than red plant communities;(2)for two-color plant communities,the optimal color proportion was 55%+45%,and the green+yellow and green+red color combinations induced a stronger relaxation effect;(3)for three-color plant communities,the relaxation effect was strongest when the color proportion was 55%green+25%yellow+20%red.These data would provide a plant color matching in future plant landscape design,which may be helpful for creating healthy and relaxing environments.

关键词： Plant community Color type Color ratio Electroencephalography Subjective questionnaire