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Dynamic Identification and Evolution of Urban-suburban-rural Transition Zones Based on the Blender of Natural and Humanistic Factors: A Case Study of Chengdu, China

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Chinese Geographical Science 2024年第5期34卷 791-809页

作者： DENG Wei JIANG Zhenyuan ZHANG Shaoyao REN Ping ZHANG Hao WANG Zhanyun The Faculty Geography resources Science Sichuan Normal UniversityChengdu 610101China Sustainable Development Research Center of resources and environment in Western Sichuan Sichuan Normal UniversityChengdu 610101China Institute of Mountain Hazards and environment Chinese Academy of SciencesChengdu 610041China

Urban-suburban-rural(U-S-R)zones exhibit distinctive transitional characteristics in interaction between human and nature.U-S-R transition zones(U-S-RTZ)are also highlighting the function diversity and landscape heterogeneity across territorial *** a super megacity in western China,Chengdu’s rapid urbanization has driven the evolution of U-S-R spaces,resulting in a sequential *** promote the high-quality spatial development of urban-rural region in a structured and efficient manner,it is essential to con-duct a scientific examination of the multidimensional interconnection within the U-S-RTZ *** proposing a novel identifica-tion method of U-S-RTZ and taking Chengdu,China as a case study,grounded in a blender of natural and humanistic factors,this study quantitatively delineated and explored the spatial evolutions of U-S-RTZ and stated the optimization orientation and sustainable devel-opment strategies of the production-living-ecological spaces along the U-S-R *** results show that:1)it is suitable for the quantitative analysis of U-S-RTZ by established three-dimensional identification system in this study.2.In 1990-2.2.,the urban-sub-urban transition zones(U-STZ)in Chengdu have continuously undergone a substantial increase,and the scale of the suburban-rural transition zones(S-RTZ)has continued to expand slightly,while the space of rural-ecological transition zones(R-ETZ)has noticeably compressed.3)The landuse dynamics within U-S-RTZ has gradually increased in *** main direction of landuse transition was from farmland to construction land or woodlands,with the expansion of construction land being the most significant.4)R-ETZ primarily focus on ecological functions,and there is a trade-off relationship between the production-ecological function within the S-RTZ,and in the U-STZ,production-living composite functions are *** study emphasizes the importance of elastic planning and precise governance within the U-

关键词： transition zone urban-suburban-rural zones spatial identification evolution mechanism Chengdu,China

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Evaluation of arsenic pollution in field-contaminated soil at the soil’s actual pH

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Journal of environmental Sciences 2024年第10期144卷 137-147页

作者： Tiancong Gao Haixia Tian Huimin Niu Mallavarapu Megharaj Wenxiang He College of Natural resources and environment Northwest A&F UniversityKey Laboratory of Plant Nutrition and Agro-environment in Northwest ChinaMinistry of AgricultureYanglingShaanxi 712100China Global Centre for environmental Remediation College of EngineeringScience and EnvironmentUniversity of NewcastleCallaghanNSW 2308Australia

The pollution and ecological risks posed by arsenic(As)entering the soil are the major environmental challenges faced by human *** phosphatase can serve as a useful indicator for assessing As contamination under specific soil pH ***,the study of phosphatase kinetics in long-term field As-contaminated soil remains unclear,presenting a significant obstacle to the monitoring and evaluation of As pollution and *** purpose of this study was to determine phosphatase activity and explore enzyme kinetics in soils subjected to long-term field As *** revealed that the soil phosphatase activity varied among the tested soil samples,depending on the concentrations of *** relationship between total As,As fractions and phosphatase activity was found to be significant through negative exponential function *** parameters,including maximum reaction velocity(Vmax),Michaelis constant(Km)and catalytic efficiency(V_(max)/K_(m)),ranged from 3.14×10^(−2.–53.88×10^(−2. mmol/(L·hr),0.61–7.92.mmol/L,and 0.46×10^(−2.–11.2.×10^(−2. hr−1,*** and Vmax/Km of phosphatase decreased with increasing As pollution,while Km was less ***,Vmax/Km showed a significant negative correlationwith all As fractions and total *** ecological doses(ED10)for the complete inhibition and partial inhibition models ranged from0.2.–70.33 mg/kg and 0.001–55.2. mg/kg,respectively,indicating that V_(max)/K_(m) can be used as an index for assessing As pollution in field-contaminated *** study demonstrated that the phosphatase kinetics parameters in the soil’s pH system were better indicators than the optimal pH for evaluating the field ecotoxicity of As.

关键词： Arsenic pollution Ecological risk Soil phosphatase Enzyme kinetics Catalytic efficiency(V_(max)/K_(m))

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Rapid Energy Exchange between In Situ Formed Bromine Vacancies and CO_(2.Molecules Enhances CO_(2.Photoreduction

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Research 2024年第2期2023卷 763-771页

作者： Qin Ren Ye He Hong Wang Yanjuan Sun Fan Dong Research Center for environmental and Energy Catalysis Institute of Fundamental and Frontier SciencesUniversity of Electronic Science and Technology of ChinaChengdu 611731China school of resources and {2. University of Electronic Science and Technology of ChinaChengdu 611731China

Photocatalytic reduction of CO_(2.into fuels provides a prospective tactic for regulating the global carbon balance utilizing renewable solar ***,CO_(2.molecules are difficult to activate and reduce due to the thermodynamic stability and chemical *** this work,we develop a novel strategy to promote the adsorption and activation of CO_(2.molecules via the rapid energy exchange between the photoinduced Br vacancies and CO_(2.*** in situ continuous wave-electron paramagnetic resonance(cw-EPR)and pulsed EPR technologies,we observe that the spin-spin relaxation time(T_(2.)of BiOBr is decreased by 198 ns during the CO_(2.photoreduction reaction,which is further confirmed by the broadened EPR *** result reveals that there is an energy exchange interaction between in situ formed Br vacancies and CO_(2.molecules,which promotes the formation of high-energy CO_(2.molecules to facilitate the subsequent reduction *** addition,theoretical calculations indicate that the bended CO_(2.adsorption configuration on the surface of BiOBr with Br vacancies caused the decrease of the lowest unoccupied molecular orbital of the CO_(2.molecule,which makes it easier for CO_(2.molecules to acquire electrons and get *** situ diffuse reflectance infrared Fourier transform spectroscopy further shows that the activated CO_(2.molecules are favorably converted to key intermediates of COOH*,resulting in a CO generation rate of 9.1μmol g^(-1)h^(-1)and a selectivity of 100%.This study elucidates the underlying mechanism of CO_(2.activation at active sites and deepens the understanding of CO_(2.photoreduction reaction.

关键词： reaction. adsorption activation

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Application of a concrete thermal pile in cooling the warming permafrost under climate change

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Advances in Climate Change Research 2024年第1期15卷 170-183页

作者： Yun-Hu SHANG Fu-Jun NIU Guo-Yu LI Jian-Hong FANG Ze-Yong GAO State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Da Xing'anling Observation and Research Station of Frozen-Ground Engineering and environment Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesJagdaqi 165000China Qinghai Research Institute of Transportation Xining 810008China

Permafrost degradation caused by climate warming is posing a serious threat to the stability of cast-in-place pile foundations in warm permafrost *** cold energy can be effectively utilized by two-phase closed thermosyphons(TPCTs)to cool the ***,we installed TPCTs in a cast-in-place pile foundation to create a unique structure called a thermal pile,which effectively utilizes the TPCTs to regulate ground *** we conducted a case study and numerical simulation to exhibit the cooling performance,and optimize the structure of the thermal *** purpose of this study is to promote the application of thermal piles in unstable permafrost *** on the findings,the thermal pile operated for approximately 53%of the entire year and effectively reduced the deep ground temperature at a rate of at least-0.1℃per ***,it successfully raised the permafrost table that is 0.35 m shallower than the natural ground *** characteristics prove highly beneficial in mitigating the adverse effects of permafrost degradation and enhancing infrastructure *** the length of the condenser section and the diameter of the TPCT in a suitable manner can effectively enhance the cooling capability of the thermal pile and ensure the long-term mechanical stability of the pile foundation even under climate warming.

关键词： Heat transfer Cold energy Warm permafrost Two-phase closed thermosyphons Cast-in-place pile foundation

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Reactive Transport Process of Earthquake-induced Hydrochemical Changes in Guanding Thermal Spring,Western Sichuan,China

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 241-249页

作者： NA Jin JIANG Xue SHI Zheming CHEN Yanmei Hubei Key Laboratory of Petroleum Geochemistry and environment(Yangtze University) Wuhan 430100China school of environmental Studies China University of GeosciencesWuhan 430074China school of Water resources and {2. China University of GeosciencesBeijing 100083China State Key Laboratory of Water Resource Protection and Utilization in Coal Mining Beijing 100000China

Earthquake-related hydrochemical changes in thermal springs have been widely observed;however,quantitative modeling of the reactive transport process is *** the present study,we apply reactive transport simulation to capture the hydrochemical responses in a thermal spring following the Wenchuan Ms 8.0 and Lushan Ms 7.0 *** first constrain deep reservoir geothermal fluid compositions and temperature by multicomponent geothermometry,and then a reactive geochemical transport model is constructed to reproduce the hydrochemical evolution *** results show that the recharge from the shallow aquifer increases gradually until it reaches a peak because of the permeability enhancement caused by the Lushan earthquake,which may be the mechanism to explain the earthquake-related hydrochemical *** contrast to the postseismic effect of the Wenchuan earthquake,the chemical evolution can be considered as hydrochemical anomalies related to the Lushan *** study proves that the efficient simulation of reactive transport processes is useful for investigating earthquake-related signals in hydrochemical time series.

关键词： earthquake hydrochemical changes reactive geochemical transport model Kangding area

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Straw return decreases polycyclic aromatic hydrocarbon (PAH) accumulation in winter wheat and human health risk by enhancing PAH dissipation in rhizosphere soil

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Pedosphere 2024年第4期34卷 699-708页

作者： Jun CAI He ZHANG Xiangyao WU Yifan LIU Yunmei WU Jinfeng WANG Chuangye ZHANG Benhua SUN Fuyong WU College of Natural resources and environment Northwest A&F UniversityYangling 712100China Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China Ministry of AgricultureYangling 712100China

Straw return in situ,a common agronomic measure in China,has been widely used not only to increase crop yields and improve soil nutrients but also to remove polycyclic aromatic hydrocarbons(PAHs)from agricultural ***,the safety risks of food crops(i.e.,human health risk of wheat grains)grown in PAHs-contaminated agricultural soils amended with crop straw remain uncertain.A pot experiment was conducted in a PAHs-contaminated agricultural soil cultivated with winter wheat under different ratios of corn straw addition(0%(control,CK),1%,2.5%,and 5%,weight/weight).Results showed that corn straw addition significantly(P2.–50.01%,11.85%–42.67%,9.78%–2..03%,and 14.16%–31.67%,respectively,compared with CK,whereas the transfer factors of PAHs from roots to straws were significantly(P2..73%–45.05%.Overall,corn straw apparently reduced PAH accumulation in winter wheat,ecological risk,and human health risk via enhancing PAH dissipation in the rhizosphere *** findings provide an important scientific basis and theoretical guidance for agricultural safety production.

关键词： corn straw addition ecological risk food crops incremental lifetime cancer risk transfer factor

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The important role of Turbidity Maximum Zone in sedimentary dynamic of estuarine mangrove swamp

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Frontiers of Earth Science 2024年第1期18卷 219-226页

作者： Tao LIU Ying LIU Baoqing HU Key laboratory of environment Change and resources Use in Beibu Gulf(Ministry of Education) Nanning Normal UniversityNanning 530001China school of Civil Engineering and Architecture Guangxi UniversityNanning 530004China

Sedimentation is a key process affecting wetland sustainability and carbon burial *** context of sea level rise,climate change and human activities,further understanding about the sedimentary dynamic in wetland is critical in predicting the landscape evolution or the change in carbon burial *** this study,based on the field hydrological observation in a mangrove system in the Nanliu River estuary,we found the net flux of suspended sediment to mangrove is 39−72.kg/m in tidal cycles with Turbidity Maximum Zone(TMZ)forming in surface layer and only is 9−18 kg/m in tidal cycles without *** higher net flux of suspended sediment to mangrove in tidal cycles with TMZ forming in surface layer is attributed to high SSC in rising tide and intense flocculation in *** significant discrepancy in sedimentation rate in the mangrove patches also can be explained by the probability of TMZ forming in the surface layer of *** future,rapid sea level rising may lead to the change of TMZ pattern in estuary,which will result in non-negligible variation in sedimentation rate in *** to the present data of sedimentation rate in wetlands,the fragility of wetlands in river estuary may be miscalculated.

关键词： mangrove wetland sedimentation Turbidity Maximum Zone Nanliu River

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Diversity and ecological assembly process of aerobic anoxygenic phototrophic bacteria in a low irradiation area,Three Gorges Reservoir

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Journal of environmental Sciences 2024年第9期143卷 116-125页

作者： Lixin Huo Anran Ma Hong Liu Xingzu Wang Cheng Song Chongqing Institute of Green and Intelligent Technology Chinese Academy of SciencesChongqing 400714China Chongqing school University of Chinese Academy of SciencesCollege of Resources and EnvironmentChongqing 400714China Key Laboratory of Reservoir Aquatic environment Chinese Academy of SciencesChongqing 400714China University of Chinese Academy of Sciences Beijing 100049China

Aerobic anoxygenic phototrophic bacteria(AAPB)are significant bacterial groups in aquatic ecosystems,known for their rapid growth and photoheterotrophic ***,the distribution and ecological assembly process of AAPB in low irradiation freshwater basins remain unclear,warranting further *** this study,we present the diversity,abundance,spatial variations,ecological process,and community interaction of AAPB in sediment of Three Gorges Reservoir(TGR)under low *** findings demonstrate the dominant genera of AAPB community that exist in the TGR area also are appeared in different waters,with some regional ***,the concentration of pufM gene,an indicator for AAPB,maintains a consistently high numerical level ranging from(2.2.±0.44)×10^(4)to(9.98±0.30)×10^(7)gene copies/*** solar irradiation is suggested as the major factor affecting AAPB,it remains unclear whether and how AAPB differ between regions due to varying solar irradiation *** results show spatial differences between total bacteria and AAPB communities,with significant differences observed only in *** and environmental factor contributed less than 10%to the spatial difference of community,with sediment type and environmental factors being the key factors influencing microbial community *** stochastic process plays a dominant role in the aggregation and replacement of AAPB communities,among which the most contribution is dispersal *** AAPB network,Yoonia and Gemmobacter are the hubs for *** results valuable insights into the AAPB communities in TGR with low irradiation.

关键词： Three Gorges Reservoir(TGR) Aerobic anoxygenic phototrophic bacteria(AAPB) Bacterial community Null model Community assembly

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Excellent alkali resistance of Fe,Ce and sulfates co-modified V_(2.O_(5)-WO_(3)/TiO_(2. catalyst for selective catalytic reduction of NO_(x) with NH_(3)

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Journal of Rare Earths 2024年第9期42卷 1682-1692,I0002页

作者： Biyi Huang Xianfang Yi Jianyi Zhang Yuqiu Liu Yanting Chen Jinsheng Chen Jinxiu Wang Center for Excellence in Regional Atmospheric environment and Key Lab of Urban Environment and HealthInstitute of Urban EnvironmentChinese Academy of SciencesXiamen361021China College of resources and environment Fujian Agriculture and Forestry UniversityFuzhou350002China Fujian Key Laboratory of Atmospheric Ozone Pollution Prevention Institute of Urban EnvironmentChinese Academy of SciencesXiamen361021China University of Chinese Academy of Sciences Beijing100049China

Improving the alkali resistance of catalysts for selective catalytic reduction of NO_(x) with NH_(3) is still a *** this work,the co-modification with Fe,Ce and sulfates on V_(2.O_(5)-WO_(3)/TiO_(2. catalysts(denoted as xSFeCeVWTi) significantly enhances its alkali resistance with K element as a representative.A series of xSFeCeVWTi catalysts was synthesized by wet impregnation with designed 0.05Fe/V, 1.5Ce/V and different S/V molar ratios *** NO_(x) conversion and K resistance of xSFeCeVWTi catalysts increase with the increase of loading amounts of sulfates but no longer further increase as the sulfates load is excessive to block the pores of catalysts and hinder the adsorption of *** optimal modified catalyst in about 2.2./V actual loading ratio,corresponding to 10.5SFeCeVWTi sample,shows over 99.0%NO_(x) conversion and N_(2. selectivity at 300-400℃ after *** interaction between Fe,Ce and V improves its redox ability but slightly weakens surface acidity,while the proper amount of sulfate species enriches surface Br?nsted acid sites but attenuates its redox ***,a balance of redox capacity and surface acidity,caused by Fe,Ce and sulfate co-modification,contributes to the excellent K resistance of 10.5SFeCeVWTi ***,the change of physicochemical properties influences the reaction mechanism which follows the Eley-Rideal mechanism on *** *** results show that the co-modification with Fe,Ce and sulfates is a good way to improve the alkali tolerance of V_(2.O_(5)-WO_(3)/TiO_(2. catalyst in industrial applications.

关键词： SCR CeO_(2. Fe_(2.O_(3) SO_(4)^(2.) K resistance K poisoning

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Response of maize growth and soil biological characteristics to planting density under fertigation in a semi-arid region

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 186-192页

作者： Peng Jiang Lei Li Dejia Xu Rui Wang Quan Sun school of Forestry and Prataculture Ningxia UniversityYinchuan 750021China Institute of Agricultural resources and environment Ningxia Academy of Agriculture and Forestry SciencesYinchuan 750002China school of Agriculture Ningxia UniversityYinchuan 750021China

Increasing the planting density can exacerbate crop competition for water,nutrients and space which results in a decline in the crop ***,the effect of increasing planting density on crop growth and soil biological characteristics in barren sandy land in the semi-arid regions are still *** this study,we investigated the effects of six planting densities(5.4×10^(4),6.45×10^(4),7.95×10^(4),9.5×10^(4),9.75×10^(4) and 10.5×10^(4) plants/hm^(2.)on maize growth,photosynthesis characteristics,yield and soil biological characteristics in barren sandy soil in the semi-arid region of Ningxia,*** results indicated that the stem diameter and spike length decreased linearly with increasing planting *** plant height,spike weight,grain weight and 100-grain weight decreased with increasing plating ***,the root length increased with increasing planting *** diameter,volume and activity increased and then decreased with increasing planting *** was no significant difference(p>0.05)in the effect of planting density on transpiration rate intercellular CO_(2. *** well,the soil microbial biomass carbon and microbial biomass nitrogen decreased with increasing planting *** soil catalase activities increased and then decreased with increasing planting *** alkaline phosphatase activity,the amounts of soil bacteria and actinomycetes increased with increasing planting ***,a moderately increasing planting density can improve maize yield when water and nutrients are *** optimal planting density was 8.2.×10^(4) plants/hm^(2. and the highest yield was 15.84 t/hm^(2. in barren sandy soil in semi-arid region of Ningxia,*** study provides a theoretical basis for high yield and high efficiency of maize.

关键词： maize growth planting density yield fertigation soil enzyme activity

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