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China released the Action Plan on Prevention and Control of Soil Pollution

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Frontiers of Environmental Science & Engineering 2016年第4期10卷 1-2页

作者： Fang Zhang guanghe li School of Environment and State Key Joint Laboratory of Environment Simulation and Pollution Control Tsinghua University Beijing10084 China

China released the Action Plan on Prevention and Control of Soil Pollution （i.e. ＂Soil Ten Chapters＂） on May 31st 2016. The plan aims to arrest the worsening situation by 2020, improve the soil quality with a comprehensively controlled risk by 2030, and form a virtuous ecosystem cycle by 2050. According to the plan,

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The effect of texture and irrigation on the soil moisture vertical-temporal variability in an urban artificial landscape： a case study of Olympic Forest Park in Beijing

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Frontiers of Environmental Science & Engineering 2015年第2期9卷 269-278页

作者： Xiaofeng ZHANG Xu ZHANG guanghe li School of Environment Tsinghua University Beijing 100084 China

Soil moisture variability in natural landscapes has been widely studied; however, less attention has been paid to its variability in the urban landscapes with respect to the possible influence of texture stratification and irrigation management. Therefore, a case study was carried out in the Beijing Olympic Forest Park to continuously monitor the soil in three typical profiles from 26 April to 11 November 2010. The texture stratification significantly affected the vertical distribution of moisture in the non- irrigated profile where moisture was mostly below field capacity. In the profile where irrigation was sufficient to maintain moisture above field capacity, gravity flow led to increased moisture with depth and thus eliminated the influence of texture. In the non-irrigated sites, the upper layer （above 80 cm） exhibited long-term moisture persis- tence with the time scale approximating the average rainfall interval. However, a coarse-textured layer wea- kened the influence of rainfall, and a fine-textured layer weakened the influence of evapotranspiration, both of which resulted in random noise-like moisture series in the deeper layers. At the irrigated site, frequent irrigation neutralized the influence of evapotranspiration in the upper layer （above 60 em） and overshadowed the influence of rainfall in the deeper layer. As a result, the moisture level in the upper layer also behaved as a random noise-like series; whereas due to deep transpiration, the moisture of the deep layer had a persistence time-scale longer than a month, consistent with characteristic time-scales found for deep transpiration.

关键词： moisture vertical distribution moisture tem-poral variation texture stratification irrigation meteorolo-gical forcing urban landscape

Impact of solids on biphasic biodegradation of phenanthrene in the presence of hydroxypropyl-β-cyclodextrin(HPCD)

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Frontiers of Environmental Science & Engineering 2010年第3期4卷 329-333页

作者： Zhenyi ZHANG Chihiro INOUE guanghe li Department of Environmental Sciences&Engineering Tsinghua UniversityBeijing 100084China Graduate School of Environmental Studies Tohoku UniversitySendai 980-8579Japan

The consequence of polycyclic aromatic hydrocarbons(PAHs)in the environment is of great *** hydrophobic properties of PAHs significantly impact phase distribution causing limited *** biodegradation has been extensively carried out by surfactants and the redeployment effect was ***,the quantitative relationship concerning the impact of solids was rarely reported.A batch of biphasic tests were carried out by introducing Mycobacterium vanbaalenii PYR-1 and hydroxypropyl-β-cyclodextrin(HPCD)into a mixture of phenanthrene solution and various glass beads(GB37-63,GB105-125,and GB350-500).The comparative results demonstrated that HPCD had little effect on microbial growth and was not degradable by bacterium.A model was proposed to describe the biodegradation *** regression results indicated that the partition coefficient kd(1.234,0.726 and 0.448 L·g–1)and the degradation rate k(0 mmol·L^(–1):0.055,0.094,and 0.112;20 mmol·L^(–1):0.126,0.141,and 0.156;40 mmol·L^(–1):0.141,0.156 and 0.184 d^(–1))were positively and negatively correlated with the calculated total surface area(TSA)of solids,*** enhanced in the presence of HPCD,and the enhancing factor f was calculated(20 mmol·L^(–1):15.16,40.01,and 145.5;40 mmol·L^(–1):13.29,37.97,and 138.4),indicating that the impact of solids was significant for the enhancement of biodegradation.

关键词： biphasic biodegradation hydroxypropyl-β-cyclodextrin(HPCD) polycyclic aromatic hydrocarbons(PAHs)

Microbial community and functional genes in the rhizosphere of alfalfa in crude oil-contaminated soil

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Frontiers of Environmental Science & Engineering 2012年第6期6卷 797-805页

作者： YiZHONG Jian WANG Yizhi SONG Yuting liANG guanghe li School of Environment Tsinghua UniversityBeijing 100084China State Key Joint Laboratory of Environmental Simulation and Pollution Control Tsinghua UniversityBeijing 100084China

A rhizobox system constructed with crude oil- contaminated soil was vegetated with alfalfa （Medicago sativa L.） to evaluate the rhizosphere effects on the soil microbial population and functional structure, and to explore the potential mechanisms by which plants enhance the removal of crude oil in soil. During the 80-day experiment, 31.6% of oil was removed from the adjacent rhizosphere （AR）; this value was 27% and 53% higher than the percentage of oil removed from the far rhizosphere （FR） and from the non-rhizosphere （NR）, respectively. The populations of heterotrophic bacteria and hydrocarbon- degrading bacteria were higher in the AR and FR than in the NR. However, the removal rate of crude oil was positively correlated with the proportion of hydrocarbon- degrading bacteria in the rhizosphere. In total, 796, 731, and 379 functional genes were detected by microarray in the AR, FR, and NR, respectively. Higher proportions of functional genes related to carbon degradation and organic remediation, were found in rhizosphere soil compared with NR soil, suggesting that the rhizosphere selectively increased the abundance of these specific functional genes. The increase in water-holding capacity and decrease in pH as well as salinity of the soil all followed the order of AR 〉 FR 〉 NR. Canonical component analysis showed that salinity was the most important environmental factor influencing the microbial functional structure in the rhizosphere and that salinity was negatively correlated with the abundance of carbon and organic degradation genes.

关键词： crude oil-contaminated soil phytoremedia-tion rhizosphere effects rhizobox functional genes

Effect of current density on groundwater arsenite removal performance using air cathode electrocoagulation

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Frontiers of Environmental Science & Engineering 2021年第6期15卷 211-219页

作者： Yanxiao Si Fang Zhang Chen Hong guanghe li Haichuan Zhang Dun liu School of Environment and State Key Joint Laboratory of Environment Simulation and Pollution Control Tsinghua UniversityBeijing 100084China Surface Engineering Division Sinopec Petroleum Exploration and Production Research InstituteBeijing 100083China School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China

Naturally occurring arsenic enrichment in groundwater poses a huge threat to human *** cathode electrocoagulation(ACEC)has recently been proposed to enhance As(Ⅲ)oxidation and lower energy *** this study,ACEC,EC/O_(2) and EC/N_(2) were evaluated with different current densities from 1 to 8 mA/cm^(2) to investigate the effect on As(Ⅲ)removal in different redox *** density had no appreciable effect on arsenic removal efficiency given the same charge in ACEC because the concentration ratio of Fe/H2O_(2) under different current densities remained ***,in EC/O_(2) and EC/N_(2),As(Ⅲ)removal was inhibited at higher current densities(4–8 mA/cm^(2)),likely because more Fe(Ⅱ)competed with As(Ⅲ)for the oxidant,leading to less effective oxidation of As(Ⅲ).In all EC systems,the$OH units generated per power consumption reached the highest value at the lowest current *** with other EC systems,the ACEC system showed lower energy consumption at all current densities due to the low energy consumption of the electrode reaction and more free radical generation.A lower current density saved more energy at the expense of time,showing the trade-off relationship between energy consumption and removal *** operation costs for As(Ⅲ)removal under optimal conditions were calculated as 0.028$/m^(3) for ACEC,0.030$/m^(3) for EC/O_(2),and 0.085$/m^(3) for EC/N_(2)

关键词： Electrocoagulation Air cathode Arsenic Current density Energy consumption

Stability of inner dump slope under coal pillar support:case study in an open‑pit coal mine

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International Journal of Coal Science & Technology 2022年第2期9卷 193-210页

作者： guanghe li Xiaoxu Yang Dong Wang Yanting Wang Xiangyu Yu College of Mining Liaoning Technical UniversityFuxin 123000LiaoningChina

The stability of an inner dump slope was investigated under the efect of coal pillar support considering the development position of *** on the instability mechanism and load distribution characteristics of the supporting coal pillar,the three-dimensional mechanical efects of the supporting coal pillar are *** the two-dimensional equivalent principle and the residual thrust method,the stability of the inner dump slope was analyzed under the efect of pillar support at diferent dump development *** quantitative efects of various factors on the inner dump slope stability were revealed,and the coal pillar shape parameters were optimized through numerical *** results indicate that the slope stability coefcient is linearly related to the top width and height of the coal pillar,slope angle,and base inclination angle,and has an exponential relation with the coal pillar strike length and slope height *** are quadratic and absolute value relations with the coal pillar outer and the inner bottom angle,*** top width of the coal pillar in the inner dump of Shengli East No.2 open-pit coal mine should be at a level of+824 m,and the optimal top width and height are 15 and 36.7 m,*** instability mechanism of the supporting and retaining coal pillar obtained by numerical simulations and the stability of the inner dump are in good agreement with the theoretical *** results provide a theoretical basis for the design,treatment,and safe implementation of similar open-pit mine slope engineering.

关键词： Inner dump Supporting coal pillar Slope stability Numerical simulation Morphological parameters

Evolution of soil DOM during thermal remediation below 100℃:concentration,spectral characteristics and complexation ability

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Frontiers of Environmental Science & Engineering 2024年第8期18卷 31-41页

作者： Wan Huang Ziren Wan Di Zheng lifeng Cao guanghe li Fang Zhang State Key Joint Laboratory of Environment Simulation and Pollution Control State Environment Protection Key Laboratory of Microorganism Application and Risk ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China National Engineering Laboratory for Site Remediation Technologies Beijing 100015China

The impact of thermal remediation on soil function has drawn increasing *** far,as the most active fraction of soil organic matter,the evolution of dissolved organic matter(DOM)during the thermal remediation lacks in-depth investigation,especially for the temperatures value below 100℃.In this study,a series of soil thermal treatment experiments was conducted at 30,60,and 90℃ during a 90-d period,where soil DOM concentration increased with heating temperature and *** molecular weight,functional groups content and aromaticity of DOM all decreased during the thermal *** excitation-emission matrices(EEM)results suggested that humic acid-like substances transformed into fulvic acid-like substances(FIII/FV increased from 0.27 to 0.44)during the heating process,and five DOM components were further identified by *** change of DOM structures and components indicated the decline of DOM stability and hydrophilicity,and can potentially change the bioavailability and *** temperature also resulted in the decline of DOM complexation ability,which may be caused by the loss of binding sites due to the decrease of polar function groups,aromatic structures and hydrophilic *** study provides valuable information about the evolution of DOM during thermal remediation,which would potentially change the fate of metal ions and the effectiveness of the post-treatment technologies in the treated region.

关键词： Thermal remediation below 100℃ Heating temperature Soil DOM concentration DOM spectral characteristics Excitation-emission matrices(EEM) Complexation ability

Three-dimensional stability calculation method for high and large composite slopes formed by mining stope and inner dump in adjacent open pits

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International Journal of Mining Science and Technology 2024年第4期34卷 507-520页

作者： Zuchao liang Dong Wang guanghe li Guangyu Sun Mingyu Yu Dong Xia Chunjian Ding College of Mining Engineering Liaoning Technical UniversityFuxin 123000China Inner Mongolia Pingxi Baiyinhua Coal Industry Co. Ltd.Xilingol League 026000China Guoneng Baorixile Energy Co. Ltd.Hulunbuir 021008China

The 2D limit equilibrium method is widely used for slope stability ***,with the advancement of dump engineering,composite slopes often exhibit significant 3D mechanical ***,it is of significant importance to develop an effective 3D stability calculation method for composite slopes to enhance the design and stability control of open-pit slope *** the composite slope formed by the mining stope and inner dump in Baiyinhua No.1 and No.2 open-pit coal mine as a case study,this research investigates the failure mode of composite slopes and establishes spatial shape equations for the sliding *** integrating the shear resistance and sliding force of each row of microstrip columns onto the bottom surface of the strip corresponding to the main sliding surface,a novel 2D equivalent physical and mechanical parameters analysis method for the strips on the main sliding surface of 3D sliding masses is ***,a comprehensive 3D stability calculation method for composite slopes is developed,and the quantitative relationship between the coordinated development distance and its 3D stability coefficients is *** analysis reveals that the failure mode of the composite slope is characterized by cutting-bedding sliding,with the arc serving as the side interface and the weak layer as the bottom interface,while the destabilization mechanism primarily involves shear *** spatial form equation of the sliding mass comprises an ellipsoid and weak plane *** analysis revealed that when the coordinated development distance is 1500 m,the error rate between the 3D stability calculation result and the 2D stability calculation result of the composite slope is less than 8%,thereby verifying the proposed analytical method of equivalent physical and mechanical parameters and the 3D stability calculation method for composite ***,the3D stability coefficient of the composite slope exhibits an exponential co

关键词： Composite slope Destabilization mechanism 3D mechanical effect Three-dimensional stability Coordinated development distance

Relationships between loading rates and nitrogen removal effectiveness in subsurface flow constructed wetlands

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Frontiers of Environmental Science & Engineering 2008年第1期2卷 89-93页

作者： Rongshe ZHANG guanghe li Qi ZHOU Xu ZHANG Department of Environmental Science and Engineering Tsinghua UniversityBeijing 100084China College of Environmental Science and Engineering Tongji UniversityShanghai 200092China

Nitrogen removal of wetlands under 40 differ-ent inflow loadings were studied in the field during 15months. The removal efficiency of four different sets ofbeds, namely the reed bed, the Zizania caduciflor bed, themixing planting bed, and the control bed were *** outflow loading and total nitrogen (TN) removal rateof these beds under different inflow loadings and pollutionloadings were investigated. The inflow loadings of 4 sub-surface flow systems (SFS) ranged from 400 to 8000 mg·(m^(2) ·d) 21 , while outflow loadings were less than 7000 mg·(m^(2) ·d) 21 . The results showed that the inflow and outflowloading of TN removal rate in SFS presented an obviouslinear relationship. The optical inflow loading to run thesystem was between 2000 to 4000 mg·(m^(2) ·d) 21 . Averageremoval rate was between 1062 and 2007 mg·(m^(2) ·d) 21 .SFS with plant had a better removal rate than the *** removal rates of the reed and Zizania caduciflora bedwere 63% and 27% higher than the control bed,respectively. The results regarding the TN absorption ofplants indicated that the absorption amount was verylimited, less than 5% of the total removal. It proved thatplants clearly increase TN removal rates by improving thewater flow, andincreasingthe biomass, as wellas activitiesof microorganisms around the roots. The researchprovided a perspective for understanding the TN removalmechanism and design for SFS.

关键词： subsurface flow constructed wetland nitro-gen reeds Zizania caduciflora non-point pollution