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Metals content in sediments of ephemeral streams with small reservoirs(the Negev Desert)

International Journal of Sediment Research 2020年第3期35卷 269-277页

作者： Ma?gorzata Kijowska-Struga?a ?ukasz Wiejaczka Rafa? Koz?owski Judith Lekach Polish Academy of sciences Institute of Geography and Spatial OrganizationResearch Station in Szymbark Polish Academy of sciences Institute of Geography and Spatial OrganizationDepartment Polish Academy of SciencesInstitute of Geography and Spatial OrganizationDepartment of Geoenvironmental Research The Jan Kochanowski University Institute of Geography and Environmental Sciences Bar-Ilan University Department of Geography and Environment

The content of 19 metals(chromium,cobalt,nickel,strontium,arsenic,magnesium,barium,cesium,gallium,rubidium,uranium,vanadium,zinc,lead,copper,cadmium,iron,manganese,and aluminum) in sediment in three ephemeral streams(Nahal Sansana,Nahal Revivim and Nahal Pura) with reservoirs in the Negev Desert is studied *** study was done in September *** samples were collected from the surface layer of sediment(up to 10 cm) in the reservoirs and in the channels upstream and downstream of the ***,which on average,accounted for 72% dominated in the *** the spatial distribution of the particle size,sand and gravel fractions were deposited in the ***,iron,and magnesium accounted for 99% of all analyzed *** Principal Component Analysis(PCA) and Hierarchical Cluster Analysis(HCA) showed that sediment in the Negev Desert channel upstream of the reservoirs had similar concentrations of *** were also found between the analyzed *** bottom sediment in reservoirs had higher concentrations of metals than sediment upstream and downstream of the *** comparison of concentrations in upstream and downstream locations did not show any unambiguous trends because metal concentrations downstream from the reservoirs were not always lower than upstream of the *** analysis of the sediment enrichment factor(EF) showed the highest value in the reservoirs and the lowest downstream of the *** concentrations of most analyzed metals did not indicate the possibility of potential ecological risk(SQG).

关键词： Metal content Sediment Reservoir Arid zone Israel

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Spatiotemporal characteristics and influencing factors of vegetation water use efficiency on the Tibetan Plateau in 2001–2020

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Journal of Geographical sciences 2025年第1期 39-64页

作者： HE Chenyang WANG Yanjiao YAN Feng LU Qi School of Ecological and environmental science East China Normal University institute of Ecological Conservation and Restoration Chinese Academy of Forestry National Climate Center China Meteorological Administration

Water use efficiency （WUE）,as a pivotal indicator of the coupling degree within the carbon–water cycle of ecosystems,holds considerable importance in assessment of the carbon–water balance within terrestrial ***,in the context of global warming,WUE evolution and its primary drivers on the Tibetan Plateau remain *** study employed the ensemble empirical mode decomposition method and the random forest algorithm to decipher the nonlinear trends and drivers of WUE on the Tibetan Plateau in 2001–*** indicated an annual mean WUE of 0.8088 gC/mm·m2across the plateau,with a spatial gradient reflecting decrease from the southeast toward the *** manifesting monotonous trends of increase or decrease in WUE accounted for 23.64%and 9.69%of the total,***,66.67%of the region exhibited trend reversals,i.e.,39.94%of the area of the Tibetan Plateau showed transition from a trend of increase to a trend of decrease,and 26.73%of the area demonstrated a shift from a trend of decrease to a trend of *** factors accounted for 70.79%of the variability in *** leaf area index and temperature served as the major driving forces of WUE variation.

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Mercury transportation in soil via using gypsum from flue gas desulfurization unit in coal-fired power plant

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Journal of environmental sciences 2013年第9期25卷 1858-1864页

作者： Kelin Wang William Orndorff Yan Cao Weiping Pan institute for Combustion science and environmental Technology Western Kentucky University

The mercury flux in soils was investigated, which were amended by gypsums from flue gas desulphurization （FGD） units of coal- fired power plants. Studies have been carried out in confined greenhouses using FGD gypsum treated soils. Major research focus is uptakes of mercury by plants, and emission of mercury into the atmosphere under varying application rates of FGD gypsum, simulating rainfall irrigations, soils, and plants types. Higher FGD gypsum application rates generally led to higher mercury concentrations in the soils, the increased mercury emissions into the atmosphere, and the increased mercury contents in plants （especially in roots and leaves）. Soil properties and plant species can play important roles in mercury transports. Some plants, such as tall fescue, were able to prevent mercury from atmospheric emission and infiltration in the soil. Mercury concentration in the stem of plants was found to be increased and then leveled off upon increasing FGD gypsum application. However, mercury in roots and leaves was generally increased upon increasing FGD gypsum application rates. Some mercury was likely absorbed by leaves of plants from emitted mercury in the atmosphere.

关键词： flue gas desulphurization gypsums soils mercury emissions mercury uptakes mercury infiltration greenhouse tests

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An assessment of the climatic suitability of Afriski Mountain Resort for outdoor tourism using the Tourism Climate Index(TCI)

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Journal of Mountain science 2019年第11期16卷 2453-2469页

作者： Kirsten NOOME Jennifer M.FITCHETT School of geography Archaeology and Environmental Studies University of the Witwatersrand

Tourism Climatic Indices(TCIs)are widely used in the global North to quantify the climatic suitability of a destination for *** one such study has been conducted in southern Africa to *** is in a chronic shortage of research on tourism and climate change in the southern *** study presents the application of the TCI in Lesotho,calculated for the eastern Lesotho *** region has an emerging tourism sector,which primarily comprises outdoor *** include hiking,horse-riding,music festivals,mountain biking,cultural visits,sightseeing,and at the Afriski lodge,skiing and *** activities are reliant on climatic conditions that are conducive to the activity taking place,prolonged periods outdoors,and tourist satisfaction of the *** is a major determinant of both the length of season for these activities and the timing of peak tourist *** temperatures and changes in relative humidity and precipitation pose real threats to hiking,sightseeing and snow tourism at *** reliance of tourism in the region on specific climatic conditions for successful tourism prompted the use of the *** results classify the eastern Lesotho Highlands as having‘good'climatic conditions with an overall TCI score of 64 for the period *** TCI scores for the eastern Lesotho reveal a bimodal-shoulder,meaning the peak climatic conditions are in the regional summer months(December to February).This conflicts with the peak tourist seasons of summer and winter,which align with South African school holidays,and the timing of the most profitable tourism activity(skiing)which occurs during the winter months of June,July and *** is landlocked by South *** analysis for South Africa reveals more suitable climatic conditions for tourism than Lesotho,with significantly higher scores of 80-89.

关键词： Climate Tourism Climatic Index(TCI) Lesotho Highlands Outdoor tourism Snow tourism

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Cross-shore suspended sediment flux in the salt marsh pioneer zone of Chongming eastern beach in the Chang- jiang Estuary in China

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Acta Oceanologica Sinica 2010年第6期29卷 62-72页

作者： WANG Chu YAO Dongjing HE Baogen ZHOU Naisheng XU Shiyuan Department of geography Shanghai Normal University Shanghai 200234 China Department of geography College of Resource and Environmental Science East China Normal University Shanghai 200062 China

Between April 2002 and April 2003,in situ measurements of water depth,current velocity and suspended sediment content were carried out in edge region of East Chongming salt marsh and neighboring bald flat in the Changjiang （Yangtze） Estuary under different weather ***-shore suspended sediment flux was calculated and *** results show that under calm weather conditions,the current velocity process in bald field and salt marsh area varied differently during semidiurnal tidal *** to current velocity asymmetry,mean SSC during flood tide phase was 1.8 times higher than that of ebb tide *** a result,net onshore sediment flux controlled cross-shore suspended sediment transport process and salt marsh pioneer zone was generally *** was significant positive correlation between total sediment flux and quartic power of maximum water *** indicates that tidal ranges dominate suspended sediment transport and sedimentation process in the salt marsh pioneer zone under the calm weather *** sedimentation rate on the adjacent mudflat was higher than the salt marsh,which induced stable accreting of salt marsh towards the *** wind events enhanced SSC and current velocity during the semidiurnal *** the remarkable onshore net sediment flux could occur on the high marsh and mudflat close to the marsh fringe during the short period under the rough weather condition.

关键词： current velocity suspended sediment content flux salt marsh eastern beach

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Photoreductive degradation of sulfur hexafluoride in the presence of styrene

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Journal of environmental sciences 2008年第2期20卷 183-188页

作者： HUANG Li GU Dinghong Yang Longyu Xia Lanyan ZHANG Renxi HOU Huiqi institute of environmental science Fudan University Shanghai 200433 China

Sulfur hexafluoride （SF6） is known as one of the most powerful greenhouse gases in the atmosphere. Reductive photodegradation of SF6 by styrene has been studied with the purpose of developing a novel remediation for sulfur hexafluoride pollution. Effects of reaction conditions on the destruction and removal efficiency （DRE） of SF6 are examined in this study. Both initial styrene-to-SF6 ratio and initial oxygen concentration exert a significant influence on DRE. SF6 removal efficiency reaches a maximum value at the initial styrene-to-SF6 ratio of 0.2. It is found that DRE increases with oxygen concentration over the range of 0 to 0.09 mol/m^3 and then decreases with increasing oxygen concentration. When water vapor is fed into the gas mixture, DRE is slightly enhanced over the whole studied time scale. The X-ray Photoelectron Spectroscopy （XPS） analysis, together with gas chromatography-mass spectrometry （GC-MS） and Fourier Transform Infrared spectroscopy （FT-IR） analysis, prove that nearly all the initial fluorine residing in the gas phase is in the form of SiF4, whereas, the initial sulfur is deposited in the form of elemental sulfur, after photodegradation. Free from toxic byproducts, photodegradation in the presence of styrene may serve as a promising technique for SF6 abatement.

关键词： SF6 184.9 nm irradiation styrene reductive radicals photodegradation

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Prospects on mangrove knowledge services in the smart era: From plant atlas to knowledge graphs

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science China Earth sciences 2025年第1期 111-127页

作者： Zhi-Wei HOU Wenlong JING Cheng-Zhi QIN Ji YANG Qing XIA Xiaoling YIN Key Laboratory of Guangdong for Utilization of Remote Sensing and Geographical Information System Guangdong Open Laboratory of Geospatial Information Technology and Application Guangzhou Institute of Geography Guangdong Academy of Sciences Southern Marine science and Engineering Guangdong Laboratory (Guangzhou) State Key Laboratory of Resources and environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences School of Traffic & Transportation Engineering Changsha University of Science and Technology

Mangroves are crucial to the ecological security of the Earth and human well-being. Their management, conservation, and restoration are of great importance and necessitate the support of spatio-temporal information and multidisciplinary knowledge such as biology and ecology. Traditional knowledge services such as plant atlas provide illustrated textual knowledge of mangroves. However, this kind of service is oriented to information retrieval and is incapable of effectively mining and utilizing fragmented knowledge from multi-source heterogeneous data, facing the problem of “massive data, rare knowledge”. Knowledge graphs are capable of extracting, organizing, and fusing the knowledge contained in massive data into semantic networks that can be understood and computed by computers. They provide a solution for the realization of intelligent knowledge services. Focusing on the urgent need for mangrove knowledge acquisition, formal representation, and intelligent services, this paper proposes a research prospect on mangrove knowledge graphs and knowledge services. We first analyze the similarities and differences between various domain-specific concepts of Tupu. On this basis, we define the mangrove knowledge graph as a large-scale knowledge base that integrates multi-disciplinary knowledge and spatio-temporal information with mangrove ecosystems as the core. Then, we propose a research framework for mangrove knowledge services that can realize the transformation from multi-modal data to intelligent knowledge services, including multiple research levels such as ubiquitous data sensing and aggregation, knowledge organization and graph construction, and intelligent mangrove knowledge services. Subsequently, the methods and workflow for constructing mangrove knowledge graphs are introduced. Finally, we discuss the challenges and possible future directions of mangrove knowledge services in the smart era, including the construction of a mangrove knowledge system that integra

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DEVELOPMENT OF ATMOSPHERIC CIRCULATION AND IRREGULARITY OF EARTH

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science in China,Ser.B 1982年第5期25卷 531-546页

作者：彭公炳陆巍 institute of geography Academia Sinica science Press

In this paper, a study has been done on the interaction between the development ofatmospheric circulation and the irregularity of the earth rotation; relevant equations havebeen developed to show the probable variations of the earth’s crust and atmospheric move-ment in the event that the earth rotation changes in velocity; some discussion has beenmade about the probable variations of the direction of atmospheric movement. To verifythe aforesaid considerations and equations, a number of circulation and weather-climate factsin connection with the changes of the earth rotation velocity are presented.

关键词： DEVELOPMENT OF ATMOSPHERIC CIRCULATION AND IRREGULARITY OF EARTH

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Seasonal and spatial distributions of euphotic zone and longterm variations in water transparency in a clear oligotrophic Lake Fuxian, China

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Journal of environmental sciences 2018年第10期30卷 185-197页

作者： Qichao Zhou Yunlin Zhang Kaidi Li Licheng Huang Fengle Yang Yuanyang Zhou Junjun Chang Taihu Laboratory for Lake Ecosystem Research State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Yunnan Key Laboratory of Pollution Process and Management of Plateau Lake-Watershed Yunnan Institute of Environmental Science(Kunming China International Research Center for Plateau Lake) School of Ecology and environmental science Yunnan University

To assess the seasonal and spatial variations and long-term trends in water optical properties in Lake Fuxian, investigations based on field work in four seasons and a long-term analysis of data from 1980 to 2014 were conducted. The results show that there was no significant variation in the euphotic depth（Z（eu）） across the four seasons, and no significant correlations between Z（eu） and potential influencing factors in seasons other than summer, suggesting that the water itself may be a major factor regulating the Z（eu）in general. Nevertheless, significant differences in Z（eu） between the north region（NR） and the south region（SR） were observed in all seasonal tests except spring. This finding relates to a higher abundance of chromophoric dissolved organic matter（CDOM） in the NR due to runoff, especially in the rainy seasons（summer and autumn）.CDOM and its terrigenous component had an important impact on Z（eu）in summer, with the highest precipitation, and impacts from suspended solids and non-algal particles were also found in the NR in summer. The Secchi disk depth in the lake decreased clearly over the years,with significantly negative correlations with the increasing permanganate index and air temperature, implying that organic contaminants（CDOM and/or phytoplankton） are important regulators of water transparency. We estimate that the combined effects of climate warming and changes in land use and land cover are also indirect regulating factors. These findings should be considered in the protection of Lake Fuxian, owing to the importance of light penetration in aquatic ecosystems.

关键词： Photosynthetic active radiation Diffuse attenuation coefficient Euphotic depth Secchi disk depth Chromophoric dissolved organic matter Yunnan-Guizhou Plateau

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Boosting Photocatalytic Performance of Cu-Mn Co-doped CeO2 Nanoparticles for Tetracycline Degradation

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Journal of Wuhan University of Technology(Materials science) 2025年第1期 42-48页

作者：徐荣琪 MI Jianxin 王树林徐慢 ZHU Li BAI Lei TANG Dandan LEI Yu Engineering Research Center of environmental Materials and Membrane Technology of Hubei Province School of Materials Science and Engineering Wuhan Institute of Technology Shaanxi Coal Chemical Industry Technology Research institute Co. Ltd.

Cu-Mn co-doped CeO2photocatalyst was successfully synthesized by the sol-gel method to assess its capability in degrading *** and TEM results showed that Cu and Mn were successfully co-doped into CeO2without forming heterostructure,XPS and photoelectrochemical results revealed that Mn ions doping amplified the generation of photo-induced charge carriers,while Cu ions doping significantly facilitated the interfacial charge transfer ***,the optimized Cu3Mn2CeO2nanoparticles exhibited the highest TC removal efficiency,achieved a rate of 78.18% and maintained a stable cycling performance.

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