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Journal of Mountain Science 2020年第12期17卷 2929-2941页

作者： ZHANG Ting-yu MAO Zhong-an WANG Tao shaanxi provincial land engineering construction group land Survey Planning and Design Institute co. Ltd.Xi'an710075China

landslide susceptibility mapping is significant for landslide *** approaches have been used for landslide susceptibility prediction,however,their performances are *** study co.structed a hybrid model,namely box co.nting dimension-based kernel logistic regression model,which uses fractal dimension calculated by box co.nting method as input data based on grid cells mapping unit and terrain mapping *** performance of this model was evaluated in the application in Zhidan co.nty,shaanxi Province,***,a total of 221 landslides were identified and mapped,and 11 landslide predisposing factors were ***,the landslide susceptibility maps(LSMs) of the study area were obtained by co.structing the model on two different mapping ***,the results were evaluated with five statistical indexes,sensitivity,specificity,positive predictive value(PPV),negative predictive value(NPV) and *** statistical indexes of the model obtained on the terrain mapping unit were larger than those based on grid cells mapping *** training and validation datasets,the area under the receiver operating characteristic curve(AUC) of the model based on terrain mapping unit were 0.9374 and 0.9527,respectively,indicating that establishing this model on the terrain mapping unit was advantageous in the study *** results show that the fractal dimension improves the prediction ability of the kernel logistic *** addition,the terrain mapping unit is a more promising mapping unit in Loess areas.

关键词： Kernel logistic regression model landslide susceptibility GIS Fractal dimension

High-Density Block Transformation to Increase Natural Ventilation Based on CFD Simulation

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Fluid Dynamics & Materials Processing 2021年第1期17卷 141-157页

作者： Siqi Liu Guanqi Huang shaanxi provincial land engineering construction group co. Ltd.Xi’an710075China Institute of land engineering and Technology Shaanxi Provincial Land Engineering Construction Group Co.Ltd.Xi’an710075China Center for Housing Innovations Chinese University of Hong KongHong Kong Guangzhou Urban Planning&Design Survey Research Institute Guangzhou510060China

Many co.ntries in the world have experienced extremely rapid urbanization during recent decades. The rapiddevelopment of densely populated areas has produced many urban environmental problems. This researchexplores the relationship between urban morphology and ventilation co.ditions. Through 3D modeling andco.putational Fluid Dynamics (CFD) simulation, we focus on the large scale ventilation of an extended area withseveral buildings. As a testbed, in particular, the co.e part of Kwun Tong industrial park in Hong Kong is examined, and in order to validate the approach, 10 measurement points are used to get experimental values to be usedfor co.parison (such points are located in different positions involving traffic road, pedestrian path and openspace). The error range (±0.7 m/s) indicates that the agreement between field measurement and CFD calculationis good. On the basis of design guidelines and earlier studies, the effective co.figuration (in terms of building) ofthis area is partially transformed (virtually, i.e., in the numerical simulations) in order to assess the ensuingchanges in terms of wind speed in different locations. This results in a general design and analysis methodologypotentially applicable to other areas.

关键词： CFD thermal co.fort ventilation open space

Natural vegetation restoration of Liaodong oak(Quercus liaotungensis Koidz.) forests rapidly increased the co.tent and ratio of inert carbon in soil macroaggregates

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Journal of Arid land 2019年第6期11卷 928-938页

作者： SUN Lipeng HE Lirong WANG Guoliang JING Hang LIU Guobin Institute of Soil and Water co.servation Northwest A&F UniversityYangling 712100China shaanxi provincial land engineering construction group co. Ltd.Xi'an 710075China

The lack of clarity of how natural vegetation restoration influences soil organic carbon(SOC) co.tent and SOC co.ponents in soil aggregate fractions limits the understanding of SOC sequestration and turnover in forest *** aim of this study was to explore how natural vegetation restoration affects the SOC co.tent and ratio of SOC co.ponents in soil macroaggregates(>250 μm), microaggregates(53–250 μm), and silt and clay(shaanxi, China in *** the associated effects of biomasses of leaf litter and different sizes of roots(0–0.5, 0.5–1.0, 1.0–2.0 and >2.0 mm diameter) on SOC co.ponents were studied *** showed that the co.tents of high activated carbon(HAC), activated carbon(AC) and inert carbon(IC) in the macroaggregates, microaggregates and silt and clay fractions increased with restoration ***, IC co.tent in the microaggregates in topsoil(0–20 cm) rapidly increased;peaking in the 90-year-old restored forest, and was 5.74 times higher than AC *** deep soil(20–80 cm), IC co.tent was 3.58 times that of AC *** of 0.5–1.0 mm diameter roots and leaf litter affected the co.tent of aggregate fractions in topsoil, while the biomass of >2.0 mm diameter roots affected the co.tent of aggregate fractions in deep *** the soil profiles, macroaggregates had the highest capacity for HAC *** effects of restoration ages on soil aggregate fractions and SOC co.tent were less in deep soil than in *** co.clusion, natural vegetation restoration of Liaodong oak forests improved the co.tents of SOC, especially IC within topsoil and deep *** influence of IC on aggregate stability was greater than the other SOC co.ponents, and the aggregate stability was significantly affected by the biomasses of litter, 0.5–1.0 mm diameter roots in topsoil and >2.0 mm diameter roots in deep *** vegetation restorati

关键词： activated carbon leaf litter soil organic carbon soil aggregates silt and clay shaanxi

Dynamic Modeling Framework of Sediment Trapped by Check-Dam Networks:A Case Study of a Typical Watershed on the Chinese Loess Plateau

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engineering 2023年第8期27卷 209-221页

作者： Pengcheng Sun Yiping Wu Key Laboratory of Degraded and Unused land co.solidation engineering the Ministry of Natural ResourcesShaanxi Provincial Land Engineering Construction Group Co.Ltd.Xi’an 710075China Key Laboratory of Soil and Water co.servation on the Loess Plateau of Ministry of Water Resources Yellow River Institute of Hydraulic ResearchZhengzhou 450003China Technology Innovation Center for land engineering and Human Settlement Shaanxi Provincial Land Engineering Construction Group Co.Ltd.&Xi’an Jiaotong UniversityXi’an 710115China

Check-dam construction is an effective and widely used method for sediment trapping in the Yellow River Basin and other places over the world that are prone to severe soil *** estimations of the dynamic sediment trapped by check dams are necessary for evaluating the effects of check dams and planning the construction of new *** this study,we propose a new framework,named soil and water assessment tool(SWAT)–dynamic check dam(DCDam),for modeling the sediment trapped by check dams dynamically,by integrating the widely utilized SWAT model and a newly developed module called *** then applied this framework to a typical loess watershed,the Yan River Basin,to assess the time-varying effects of check-dam networks over the past 60 years(1957–2016).The DCDam module generated a specific check-dam network to co.ceptualize the co.plex co.nections at each time step(monthly).In addition,the streamflow and sediment load simulated by using the SWAT model were employed to force the sediment routing in the check-dam *** evaluation results revealed that the SWAT-DCDam framework performed satisfactorily,with an overestimation of 11.50%,in simulating sediment trapped by check dams,when co.pared with a field survey of the accumulated sediment *** the Yan River Basin,our results indicated that the designed structural parameters of check dams have evolved over the past 60 years,with higher dams(37.14%and 9.22%increase for large dams and medium dams,respectively)but smaller co.trolled areas(46.03%and 10.56%decrease for large dams and medium dams,respectively)in recent *** retained by check dams co.tributed to approximately 15.00%of the total sediment load reduction in the Yan River during 1970–***,our developed framework can be a promising tool for evaluating check-dam effects,and this study can provide valuable information and support to decision-making for soil and water co.servation and check-dam planning and management.

关键词： Check dams Dynamic check dam(DCDam) Loess Plateau Sediment trapping SWAT

Influence of phosphate on deposition and detachment of TiO2 nanoparticles in soil

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Frontiers of Environmental Science & engineering 2019年第5期13卷 163-173页

作者： Zhan Wang Chongyang Shen Yichun Du Yulong Zhang Baoguo Li Department of Soil and Water Sciences China Agricultural UniversityBeijing 100193China co.lege of land and Environment Shenyang Agricultural UniversityShenyang 110866China Key Laboratory of Degraded and Unused land co.solidation engineering Ministry of Land and ResourcesShaanxi Provincial Land Engineering Construction Group Co.Ltd.Xi’an 710075China

The widespread use of TiO2 nanoparticles (NPs) makes inevitable their release into the soil. Phosphate is also widespread within soil, and is likely co.resent with TiO2 NPs. However, the influence of phosphate on deposition/release— and thereby on transport— of TiO2 NPs in soil is yet to be elucidated. In this study we co.ducted saturated co.umn experiments to systematically examine the transport of TiO2 NPs in soil amended with phosphate at different ionic strengths (ISs) (1, 10, 100 mmol/L NaCl) and pHs (4 and 9). Results show that the deposition of TiO2 NPs decreased with decreasing IS, increasing pH, and when soil absorbed phosphate. These observations are qualitatively in agreement with Derjaguin-landau-Verwey-Overbeek (DLVO) interaction energy calculations, because the repulsive energy barrier is larger and seco.dary minimum depth is smaller at a lower IS, higher pH, and in the presence of phosphate. Acco.dingly, both primary- and seco.dary-minimum deposition were inhibited. Interestingly, although the deposition was less at higher pH and in the presence of phosphate, the subsequent spontaneous detachment and detachment by reduction of solution IS in these cases were greater. In addition, the presence of phosphate in the solution can cause a small quantity of attached TiO2 NPs to detach, even without perturbations of physical and chemical co.ditions. Our study was the first to investigate the influence of phosphate on detachment of TiO2 NPs and the results have important implication for accurate prediction of fate and transport of TiO2 NPs in subsurface environments.

关键词： Phosphate TiO2 nanoparticles Transport Soil Deposition Detachment

Spatiotemporal variations in eco.ystem services and their trade-offs and synergies against the background of the gully co.trol and land co.solidation project on the Loess Plateau,China

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Journal of Arid land 2024年第1期16卷 131-145页

作者： WANG Jing WEI Yulu PENG Biao LIU Siqi LI Jianfeng Key Laboratory of Degraded and Unused land co.solidation engineering Ministry of Natural and ResourcesXi'an 710075China Institute of land engineering and Technology Shaanxi Provincial Land Engineering Construction Group Co.Ltd.Xi'an 710021China School of Human Settlements and Civil engineering Xi'an Jiaotong UniversityXi'an 710049China shaanxi Key Laboratory of land co.solidation Xi'an 710064China

Studying the spatiotemporal variations in eco.ystem services and their interrelationships on the Loess Plateau against the background of the gully co.trol and land co.solidation(GCLC)project has significant implications for eco.ogical protection and quality development of the Yellow River ***,in this study,we took Yan'an City,shaanxi Province of China,as the study area,selected four typical eco.ystem services,including soil co.servation service,water yield service,carbon storage service,and habitat quality service,and quantitatively evaluated the spatiotemporal variation characteristics and trade-offs and synergies of eco.ystem services from 2010 to 2018 using the Integrated Valuation of Eco.ystem Services and Trade-offs(InVEST)*** also analysed the relationship between the GCLC project and regional eco.ystem service changes in various regions(including 1 city,2 districts,and 10 co.nties)of Yan'an City and proposed a co.rdinated development strategy between the GCLC project and the eco.ogical *** results showed that,from 2010 to 2018,soil co.servation service decreased by 7.76%,while the other three eco.ystem services changed relatively little,with water yield service increasing by 0.56% and carbon storage service and habitat quality service decreasing by 0.16% and 0.14%,*** eco.ogical environment of Yan'an City developed in a balanced way between 2010 and 2018,and the four eco.ystem services showed synergistic relationships,among which the synergistic relationships between soil co.servation service and water yield service and between carbon storage service and habitat quality service were *** GCLC project had a negative impact on the eco.ystem services of Yan'an City,and the impact on carbon storage service was more *** study provides a theoretical basis for the scientific evaluation of the eco.ogical benefits of the GCLC project and the realization of a win-win situation between food security and e

关键词： eco.ystem services trade-offs and synergies gully co.trol and land co.solidation habitat quality Integrated Valuation of Eco.ystem Services and Trade-offs(InVEST)model Loess Plateau

Sand stabilization effect of feldspathic sandstone during the fallow period in Mu Us Sandy land

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Journal of Geographical Sciences 2015年第4期25卷 428-436页

作者： HAN Jichang shaanxi provincial land engineering construction group co. Ltd. Xi'an 710075 China Key Laboratory of Degraded and Unused land co.solidation engineering the Ministry of Land and Re-sources of China Xi'an 710075 China Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China

Depended on the analysis of ground snow situation, soil moisture loss speed and soil structure after planting crops of Mu Us Sandy land remedied with feldspathic sandstone in the fallow period, it is co.cluded that feldspathic sandstone mixed with sand improved the sand stabilization in the governance of Mu Us Sandy land in the fallow period. The sandy land remedied with feldspathic sandstone had big snow co.erage, 25%-75% higher than normal sand; soil moisture losses slowed down, and moisture co.tent rose by over 3 times; soil structure had been improved, and water stable aggregate co.tent increased by 6.52%-18.04%; survival rate of protection forest increased to 85%; and ground flatness is less than 1%. The above co.ditions weakened sand rising co.ditions of Mu Us Sandy land in the fallow period and formed two protective layers of snow co.er and soil frozen layer under co.d weather so as to prevent against wind erosion.

关键词： feldspathic sandstone sand stabilization Mu Us Sandy land desertification land co.solidation

Effects of long-term cultivation practices and nitrogen fertilization rates on carbon stock in a calcareous soil on the Chinese Loess Plateau

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Journal of Arid land 2018年第1期10卷 129-139页

作者： CAI Miao CHEN Zhujun ZHOU Jianbin HAN Jichang SHI Qianyun co.lege of Natural Resources and Environment Northwest A&F UniversityYangling 712100China shaanxi provincial land engineering construction group Xi'an 710075China

Soil organic carbon （SOC） and soil inorganic carbon （SIC） are important C pools in the Loess Plateau of Northwest China, however, variations of SOC and SIC stocks under different cultivation practices and nitrogen （N） fertilization rates are not clear in this area. A long-term field experiment started in June 2003 was co.ducted to investigate the SOC and SIC stocks in a calcareous soil of the Chinese Loess Plateau under four cultivation practices, i.e., fallow （FA）, co.ventional cultivation （CC）, straw mulch （SM）, and plastic film-mulched ridge and straw-mulched furrow （RF）, in co.bination with three N fertilization rates, i.e., 0 （NO）, 120 （N120）, and 240 （N240） kg N/hm2. Results indicate that the crop straw addition treatments （SM and RF） increased the co.tents of soil microbial biomass C （SMBC） and SOC, and the SOC stock increased by 10.1%-13.3% at the upper 20 cm soil depth in co.parison to the 8-year fallow （FA） treatment. Meanwhile, SIC stock significantly increased by 19% at the entire tested soil depth range （0-100 cm） under all crop cultivation practices in co.parison to that of soil exposed to the long-term fallow treatment, particularly at the upper 60 cm soil depth. Furthermore, moderate N fertilizer application （120 kg N/hm2） increased SOC stock at the upper 40 cm soil depth, whereas SIC stock decreased as the N fertilization rate increased. We co.clude that the co.bined application of crop organic residues and moderate N fertilization rate co.ld facilitate the sequestrations of SOC and SIC in the calcareous soil.

关键词： calcareous soil cultivation practices N appfication rate soil C stock Loess Plateau

Effects of water and nitrogen co.ditions under surge-root irrigation on growth and yield of apple trees

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排灌机械工程学报 2023年第2期41卷 179-186页

作者： YIN Yongle FEI Liangjun LI Zhe LIU Teng LI Zhongjie HAO Kun PENG Youliang Institute of Water Resources and Hydroelectric engineering Xi′an University of TechnologyXi′anShaanxi 710048China shaanxi provincial land engineering construction group Land Survey Planning and Design InstituteXi′anShaanxi 710064China Rural Revitalization Planning and Development Guidance Center of Yulin YulinShaanxi 719000China

In order to explore the effects of different irrigation and nitrogen application on growth cha-racteristics and yield of apple trees under surge-root irrigation in mountainous areas of northern shaanxi, field experiments were carried out with different apple trees. Three irrigation levels were applied: 85%-100%(H1), 70%-85%(H2) and 55%-70%(H3) of the field water capacity, respectively, and three nitrogen levels were N1(360 g/plant), N2(240 g/plant) and N3(120 g/plant). The results show that irrigation and nitrogen application has significant effects on new shoot length, flowering and fruit setting, fruit diameter, fruit volume and yield of apple. The leaf area index(LAI) shows a single trend during the growth period, and the peak value appears in the middle of July. Under the same irrigation level, co.pared with N3, N1 increases in yield, new shoot length, LAI, transverse diameter, longitudinal diameter, volume, flowering and fruit setting by 17.91%, 28.31%, 18.75%, 11.38%, 10.13%, 36.60%, 20.92% and 5.19%, respectively, while N2 also increases by 12.40%, 15.63%, 4.86%, 5.40%, 5.11%, 17.01%, 26.17% and 13.74%, respectively. The rate of flowering and fruit setting decreases with the increase of nitrogen application. Under the same nitrogen level, co.pared with H3, H1 increases in yield, new shoot length, LAI, transverse diameter, longitudinal diameter, volume, flowering and fruit setting by 34.65%, 15.49%, 30.77%, 3.93%, 4.95%, 12.86%, 33.15% and 28.62%, respectively, while H2 also increases by 33.67%, 16.42%, 67.52%, 3.81%, 2.97%, 11.57%, 43.45% and 27.26%, respectively. The rate of flowering and fruit setting decreases first and then increases with the increase of irrigation amount. co.pared with H3N3, the yield of other treatments increases by 2.69%-52.20%, while H2N1 treatment has the highest yield(26 852.55 kg/ha). co.sidering from the point of view of promoting growth and increasing yield, the best water and nitrogen co.bination mode of mountain apple in northe

关键词： mountain apple surge-root irrigation irrigation nitrogen growth yield

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Feasibility of Isolation Remediation Technology for Heavy Metal co.taminated Soil

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Asian Agricultural Research 2017年第12期9卷 28-29,32页

作者： Pengfeng LI Wei LIU Shuguang WANG shaanxi Province land engineering construction group shaanxi provincial land engineering construction group Mining Development and Environmental Management co. Ltd

This paper discussed current situations of researches about the isolation remediation technology " soil barrier and landfill technology" and " physical isolation remediation technology" for heavy metal co.taminated soil in mining *** view of defects of current technologies,it introduced a new isolation remediation technology,of which the new isolation materials were mixed by slaked lime,soil,find sand,and clay mineral in certain *** new isolation remediation technology is expected to realize isolation remediation of heavy metal co.bined pollution of soil through chemical passivation of slaked lime and physical adsorption function of clay minerals or activated carbons.

关键词： Soil co.bined pollution Heavy metal Isolation remediation