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Annual growth of Fagus orientalis is limited by spring drought conditions in Iran’s Golestan Province

Journal of Forestry Research 2024年第1期35卷 128-142页

作者： Khalil Ghorbani Jahangir Mohammadi Laleh Rezaei Ghaleh department of water engineering Faculty of Water and Soil EngineeringGorgan University of Agricultural Sciences and Natural ResourcesGorganIran department of Forestry Gorgan University of Agricultural Sciences and Natural ResourcesGorganIran department of water engineering Faculty of AgricultureUrmia UniversityUrmiaIran

Due to the lack of a uniform and accurate defi-nition of‘drought’,several indicators have been introduced based on different variables and methods,and the efficiency of each of these is determined according to their relationship with *** relationship between two drought indices,SPI(standardized precipitation index)and SPEI(standard-ized precipitation-evapotranspiration index)in different sea-sons was investigated using annual rings of 15 tree samples to determine the effect of drought on the growth of oriental beech(Fagus orientalis Lipsky)in the Hyrcanian forests of northern *** different evapotranspiration calcula-tion methods were evaluated on SPEI efficiency based on Hargreaves-Samani,Thornthwaite,and Penman-Monteith methods using the step-by-step M5 decision tree regression *** results show that SPEI based on the Penman-Monteith in a three-month time scale(spring)had similar temporal changes and a better relationship with annual tree rings(R^(2)=0.81)at a 0.05 significant *** change and a decreasing trend in the time series of annual tree rings are similar to the variation in the SPEI based on the Penman-Monteith *** affecting evapotranspiration,temperature,wind speed,and sunshine hours(used in the Penman-Monteith method),increased but precipitation *** non-linear modeling methods,SPEI based on Penman-Monteith best illustrated climate changes affecting tree growth.

关键词： Climate change Drought index Hyrcanian forests SPEI'Annual growth rings Fagus orientalis

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Sacrificial piles as a countermeasure against local scour around underwater pipelines

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water Science and engineering 2024年第2期17卷 187-196页

作者： Forough Raeisi Seyed Mohammad Ali Zomorodiann Masih Zolghadr Hazi Mohammad Azamathulla department of water engineering Shiraz UniversityShiraz ***Iran department of water Sciences engineering Jahrom UniversityJahrom ***Iran department of Civil and Environmental engineering The University of the West IndiesSt.Augustine CampusTrinidad 331310Republic of Trinidad and Tobago

Local scour around pipelines crossing rivers or in marine environments is a significant *** can lead to failure of the pipelines resulting in environmental side effects and economic *** study developed an experimental method to reduce local scour around pipelines with a steady flow of clear water by installing cylindrical and cubical sacrificial *** sizes of sacrificial piles were examined in a linear *** piles were installed on the upstream side of the pipeline at three *** scour depth reduction rates below the pipeline were *** results showed that sacrificial piles could protect a pipeline from local scour.A portion of scoured sediment around the sacrificial piles was deposited beneath the *** sediment accumulation reduced the scour depth beneath the *** of the experimental results demonstrated that the size of piles(d),the spacing between piles,and the distance between the pipe and piles(Xp)were the variables that reduced the maximum scour beneath the pipeline with a diameter of *** the piles with d=0.40D and 0.64D,X_(p)=4OD was the optimal distance to install a group of piles,and cubical piles could mitigate scour more effectively than cylindrical piles under similar *** the piles with d=D,the greatest reduction in scour depth was achieved at X_(p)=50D with any desired spacings between piles,and cylindrical piles in this dimension could protect the pipeline against scour more effectively than cubical piles.

关键词： Clear water River crossing pipeline Local scour Self-burial process Sediment transport

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Fundamentals and progress of the manifold method based on independent covers

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Science China(Technological Sciences) 2024年第4期67卷 966-991页

作者： SU HaiDong LIN ShaoZhong XIE ZhiQiang GONG YaQi QI YongFeng Material and engineering Structure department Yangtze River Scientific Research InstituteWuhan 430010China Research Center of water engineering Safety and Disaster Prevention of Ministry of water Resources Wuhan 430010China

Aiming to solve mesh generation,computational stability,accuracy control,and other problems encountered with existing numerical methods,such as the finite element method and the finite volume method,a new numerical computational method for continuum mechanics,namely the manifold method based on independent covers(MMIC),is proposed based on the concept of mathematical manifolds,to form partitioned series solutions of partial differential *** partitions,the cover meshes have the characteristics of arbitrary shape,arbitrary connection,and arbitrary *** are expected to fundamentally solve the mesh generation problem and can also simulate the precise geometric boundaries of the CAD model and strictly impose boundary *** the selection of series solutions,local analytical solutions(such as series solutions at crack tips and series solutions in infinite domains)or proper forms of complete series can be used to reflect the local or global characteristics of the physical field to accelerate *** applications are presented.A new method of beam,plate,and shell analysis is *** deformation characteristics of beams,plates,and shells are simulated with polynomial series of suitable forms,and the analysis of curved beams and shells with accurate geometric representation is *** the static elastic analysis of two-dimensional structures,a mesh splitting algorithm is proposed,and h-p version adaptive analysis is carried out with error ***,automatic computation integrated with CAD is *** analysis is also attempted for the solution of differential equations of *** the one-dimensional convection-diffusion equation and Burgers equation,calculation results with high precision are obtained in strong convection and shock wave simulations,avoiding nonphysical *** solving the two-dimensional incompressible Navier-Stokes equation is also *** series solution formula is used to o

关键词： series solutions mesh generation adaptive analysis fixed meshes numerical manifold method

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Synergistic effect of adsorption and photocatalytic degradation of oilfield-produced water by electrospun photocatalytic fibers of Polystyrene/Nanorod-Graphitic carbon nitride

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Journal of Environmental Sciences 2024年第7期141卷 287-303页

作者： Parisa Azmoon Mehrdad Farhadian Alireza Pendashteh Amir H.Navarchian department of Chemical engineering Faculty of EngineeringUniversity of IsfahanIsfahanIran department of Chemical engineering Faculty of EngineeringUniversity of GuilanRashtIran department of water and Environmental engineering Caspian Sea Basin Research CenterUniversity of GuilanRashtIran

Graphitic carbon nitride with nanorod structure(Nr-GCN)was synthesized using melamine as a precursor without any other reagents by hydrothermal pretreatment ***,FTIR,SEM,N_(2)adsorption-desorption from BET,UV-Vis DRS spectroscopy,and photoluminescence were used to characterize the prepared ***,the photoelectrochemical behavior of nanoparticles was studied by photocurrent transient response and cyclic voltammetry ***(PS)fibrous mat was fabricated by electrospinning technique and used as a support for the stabilization of the *** performance of the synthesized nanoparticles and photocatalytic fibers(PS/Nr-GCN)was evaluated in oilfield-produced water treatment under visible light *** this process,oil contaminants were adsorbed by hydrophobic polystyrene fibers and simultaneously degraded by *** removal efficiency of chemical oxygen demand(COD)has been obtained 96.6%and 98.4%by Nr-GCN and PS/Nr-GCN,respectively,at the optimum conditions of pH4,photocatalyst dosage 0.5 g/L,COD initial concentration 550 mg/L,and illumination time 150 *** gas chromatography-mass spectroscopy analysis results showed 99.3%removal of total petroleum hydrocarbons using photocatalytic fibers of PS/*** results demonstrated that the GCN has outstanding features like controllable morphology,visible-light-driven,and showing high potential in oily wastewater ***,the synergistic effect of adsorption and photocatalytic degradation is an effective technique in oilfield-produced water treatment.

关键词： Graphitic carbon nitride(GCN) Nanorod structure Polystyrene fibrous mat Photocatalytic fibers Oilfield-produced water(OPW)

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Stability behavior of the Lanxi ancient flood control levee after reinforcement with upside-down hanging wells and grouting curtain

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Journal of Mountain Science 2024年第1期21卷 84-99页

作者： QIN Zipeng TIAN Yan GAO Siyuan ZHOU Jianfen HE Xiaohui HE Weizhong GAO Jingquan School of water Conservancy and Environment engineering Zhejiang University of Water Resources and Electric PowerHangzhou 310018China department of Civil engineering Imperial College LondonLondonSW71BFEngland Lanxi water Affairs Bureau Lanxi 321102China Zhejiang water Conservancy engineering Consulting Co. LtdHangzhou 310051China

The stability of the ancient flood control levees is mainly influenced by water level fluctuations, groundwater concentration and rainfalls. This paper takes the Lanxi ancient levee as a research object to study the evolution laws of its seepage, displacement and stability before and after reinforcement with the upside-down hanging wells and grouting curtain through numerical simulation methods combined with experiments and observations. The study results indicate that the filled soil is less affected by water level fluctuations and groundwater concentration after reinforcement. A high groundwater level is detrimental to the levee's long-term stability, and the drainage issues need to be fully considered. The deformation of the reinforced levee is effectively controlled since the fill deformation is mainly borne by the upside-down hanging wells. The safety factors of the levee before reinforcement vary significantly with the water level. The minimum value of the safety factors is 0.886 during the water level decreasing period, indicating a very high risk of the instability. While it reached 1.478 after reinforcement, the stability of the ancient levee is improved by a large margin.

关键词： Stability analysis Multiple factors Antiseepage reinforcement Upside-down hanging well Grouting curtain Ancient levee

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In situ digital testing method for quality assessment of soft soil improvement with polyurethane

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Journal of Rock Mechanics and Geotechnical engineering 2024年第5期16卷 1732-1748页

作者： X.F.Wang C.J.Wang W.V.Yue Z.J.Zhang Z.Q.Yue department of Civil engineering China University of Geosciences (Beijing)BeijingChina department of water Science and engineering Zhengzhou UniversityZhengzhouChina department of Geotechnical engineering Tongji UniversityShanghaiChina department of Civil engineering The University of Hong KongChina

This study purposes an in situ testing method on quality assessment of soil *** drilling data includes the spatial distribution and in situ strength of untreated and treated soil along three different drillholes measured by on-site drilling monitoring *** factual drilling data can characterize the degree of soil improvement by penetration injection with permeable *** from on-site drilling monitoring shows that the linear zones represent constant drilling speeds shown in the plot of drill bit advancement *** drilling time,which indicates the spatial distributions of soil *** soil profile at the study site is composed of four layers,which includes fill,untreated silty clay,treated silty clay,and mucky *** results of soil profile are verified by the parallel site *** constant drilling speeds profile the coring-resistant strength of drilled *** comparing with the untreated silty clay,the constant drilling speeds of the treated silty clay have been decreased by 13.0-62.8%.Two drilling-speed-based indices of 61.2%and 65.6%are proposed to assess the decreased average drilling speed and the increased in situ strength of treated silty *** tests,*** compressive strength(UCS)test,have been performed with core sample to investigate and characterize in situ strength by comparing that with drilling *** show that the average predicted strengths of treated silty clay are 2.4-6.9 times higher than the average measured strength of untreated silty *** UCS-based indices of 374.5%and 344.2%verified the quality assessment(QA)results by this new in situ *** method provides a cost-effective tool for quality assessment of soil improvement by utilizing the digital drilling data.

关键词： Drilling process monitoring system Hydraulic rotary drilling process Constant drilling speed Soil improvement Quality assessment

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Hydrodynamic Assessment of A New Nature-Based Armour Unit on Rubble Mound Breakwater for Coastal Protection

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China Ocean engineering 2024年第3期38卷 439-452页

作者： Ehsan SAFA Alireza MOJTAHEDI Abdolmajid MOHAMMADIAN Mohamad Ali Lotfollahi YAGHIN department of water Resources engineering Faculty of Civil EngineeringUniversity of TabrizTabriz ***Iran Faculty of Civil engineering University of OttawaOttawa K1H 8M5Canada

This research proposes a novel nature-based design of a new concrete armour unit for the cover layer of a rubblemoundbreakwater. Armour units are versatile with respect to shape, orientation, surface condition details, and ***, a detailed analysis is required to investigate the exact state of their hydraulic interactions and structuralresponses. In this regard, the performance results of several traditional armour units, including the Antifer cube,Tetrapod, X-block and natural stone, are considered for the first step of this study. Then, the related observed resultsare compared with those obtained for a newly designed (artificial coral) armour unit. The research methodology utilizesthe common wave flume test procedure. Furthermore, several verified numerical models in OpenFOAM code areused to gain the extra required data. The proposed armour is configured to provide an effective shore protection as anenvironmental-friendly coastal structure. Thus it is designed with a main trunk including deep grooves to imitate thetypical geometry of a coral type configuration, so as to attain desirable performance. The observed results and ananalytic hierarchy process (AHP) concept are used to compare the hydraulic performance of the studied traditionaland newly proposed (artificial coral) armour units. The results indicate that the artificial coral armour unit demonstratesacceptable performance. The widely used traditional armour units might be replaced by newer designs for betterwave energy dissipation, and more importantly, for fewer adverse effects on the marine environment.

关键词： rubble mound breakwater hydraulic interaction armour unit analytic hierarchy process numerical model

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What control the spatial patterns and predictions of runoff response over the contiguous USA?

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Journal of Geographical Sciences 2024年第7期34卷 1297-1322页

作者： JIANG Shanhu DU Shuping REN Liliang GONG Xinglong YAN Denghua YUAN Shanshui LIU Yi YANG Xiaoli XU Chongyu The National Key Laboratory of water Disaster Prevention Hohai UniversityNanjing210098China College of Hydrology and water Resources Hohai UniversityNanjing210098China School of water Conservancy&Civil engineering Northeast Agricultural UniversityHarbin150030China department of water Resources China Institute of Water Resources and Hydropower ResearchBeijing100038China department of Geosciences University of OsloOsloNorway

Understanding the nonlinear relationship between hydrological response and key factors and the cause behind this relationship is vital for water resource management and earth system *** this study,we undertook several steps to explore the ***,we partitioned runoff response change(RRC)into multiple components associated with climate and catchment properties,and examined the spatial patterns and smoothness indicated by the Moran's Index of RRC across the contiguous United States(CONUS).Subsequently,we employed a machine learning model to predict RRC using catchment attribute predictors encompassing climate,topography,hydrology,soil,land use/cover,and ***,we identified the primary factors influencing RRC and quantified how these key factors control RRC by employing the accumulated local effect,which allows for the representation of not only dominant but also secondary ***,we explored the relationship between ecoregion patterns,climate gradients,and the distribution of RRC across *** findings indicate that:(1)RRC demonstrating significant connections between catchments tends to be well predicted by catchment attributes in space;(2)climate,hydrology,and topography emerge as the top three key attributes nonlinearly influencing the RRC patterns,with their second-order effects determining the heterogeneous patterns of RRC;and(3)local Moran's I signifies a collaborative relationship between the patterns of RRC and their spatial smoothness,climate space,and ecoregions.

关键词： hydrological response prediction machine learning accumulated local effect Moran’s Index large-sample study

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Biochar regulates biogeochemical cycling of iron and chromium in a soil-rice system by stimulating Geobacter and Clostridium

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Pedosphere 2024年第5期34卷 929-940页

作者： Min XU Yang LIN Jing MA Lulu LONG Chao CHEN Gang YANG Chun SONG Jun WU Xiaohong ZHANG Peng GAO College of Environmental Science Sichuan Agricultural University Soil Water and Ecosystem Sciences Department University of Florida College of water Conservancy and Hydropower engineering Sichuan Agricultural University department of Environmental and Occupational Health University of Pittsburgh School of Public Health

In soil-rice systems,microbial reduction of iron （Fe） has been recognized as a crucial biogeochemical process that regulates Fe and chromium （Cr）translocation;however,the underlying processes are *** investigate the impacts of biochar on the biochemical cycling of Fe and Cr and their toxicity to rice,maize straw biochar was applied at 1%（weight/weight） to a paddy soil spiked with 300 mg kg-1Cr under two phosphorus （P） levels (0 or 90 mg kg-1) in a pot *** key microbial groups affecting Fe dissimilatory reduction and their environmental drivers were *** inhibited root Cr uptake by 36%,owing to the promoted iron plaque （IP） formation on the rice root *** analysis showed that Fe concentration in pore water was strongly linked to the abundances of Geobacter （r=0.81–0.94,Pwater P concentrations were the key determinants influencing Fe-reducing bacterial abundances,accounting for 42%and 32%of the variation in community composition,***,biochar increased Fe and P concentrations in root cell walls,which retained more ***,Cr stress in rice under biochar treatment was relieved through increasing IP formation and altering subcellular *** mechanistic insights had important implications for reducing Cr uptake by rice.

关键词： chromium translocation iron plaque iron reduction maize straw biochar microbial reduction paddy soil phosphorus fertilization subcellular distribution

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An Improved Golden Jackal Optimization Algorithm Based on Multi-strategy Mixing for Solving engineering Optimization Problems

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Journal of Bionic engineering 2024年第2期21卷 1092-1115页

作者： Jun Wang Wen-chuan Wang Kwok-wing Chau Lin Qiu Xiao-xue Hu Hong-fei Zang Dong-mei Xu College of water Resources North China University of Water Resources and Electric PowerZhengzhou450046People’s Republic of China department of Civil and Environmental engineering The Hong Kong Polytechnic UniversityHong KongPeople’s Republic of China

Nowadays,optimization techniques are required in various engineering domains to find optimal solutions for complex *** a result,there is a growing tendency among scientists to enhance existing nature-inspired algorithms using various evolutionary strategies and to develop new nature-inspired optimization methods that can properly explore the feature *** recently designed nature-inspired meta-heuristic,named the Golden Jackal Optimization(GJO),was inspired by the collaborative hunting actions of the golden jackal in nature to solve various challenging ***,like other approaches,the GJO has the limitations of poor exploitation ability,the ease of getting stuck in a local optimal region,and an improper balancing of exploration and *** overcome these limitations,this paper proposes an improved GJO algorithm based on multi-strategy mixing(LGJO).First,using a chaotic mapping strategy to initialize the population instead of using random parameters,this algorithm can generate initial solutions with good diversity in the search ***,a dynamic inertia weight based on cosine variation is proposed to make the search process more realistic and effectively balance the algorithm's global and local search ***,a position update strategy based on Gaussian mutation was introduced,fully utilizing the guidance role of the optimal individual to improve population diversity,effectively exploring unknown regions,and avoiding the algorithm falling into local *** evaluate the proposed algorithm,23 mathematical benchmark functions,CEC-2019 and CEC2021 tests are *** results are compared to high-quality,well-known optimization *** results of the proposed method are compared from different points of view,including the quality of the results,convergence behavior,and *** superiority and high-quality performance of the proposed method are demonstrated by comparing the ***,to demonstrate

关键词： Golden jackal optimization Chaotic mapping Dynamic inertia weight Dimensional Gaussian variation Muskingum

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