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Fractal Characteristics of Fault Structures and Their Use for Mapping Ore-prospecting Potential in the Qitianling Area, Southern Hunan Province, China

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Acta Geologica Sinica(English Edition) 2015年第1期89卷 121-132页

作者： WANG Nan LIU Yongshun PENG Nian WU Cailai LIU Ningqiang NIE Baofeng YANG Xiaoyu State Key Laboratory of Continental Tectonics and Dynamics Institute of Geology Chinese Academy of Geological Sciences college of resource Environment and Tourism Capital Normal University School of Earth Sciences and resources China University of Geosciences

Quantitative analyses of the spatial distribution of fault structures can provide a theoretical basis for forecasting prospective ore deposits. Characteristics and complexity of fault structure distribution in the Qitianling area, Southern Hunan Province, China, were quantitatively calculated and appraised by fractal and multifractal methods to evaluate the relation between fault structures and ore-prospecting potential. The results show that the lengths of faults can be modeled as multifractals. Multifractal spectra evidently reflect the characteristics of the scaling of fault structures. The box- counting dimension value （D） of fault structures is equal to 1.656, as indicates complexity of the spatial distribution of faults and favorable structural conditions for the formation of ore deposits. Moreover, the D values of sub-regions were calculated and isopleths of their fractal dimension values were plotted accordingly. Overlay analyses of isopleths of fractal dimension values and distributions of known ore deposits show that areas with the larger fractal dimension values of fault structures have more ore deposits. This spatial coupling relationship between D values and ore deposits can be used to forecast and explore other ore deposits. On the basis of complexity theory for ore-forming systems, three exploration targets with high D values were delineated as prospective ore deposits.

关键词： Fault structures Qitianling granite Ore-prospecting potential Fractal Multifractal

Exploring the complex structural evolution of global primary product trade network

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Regional Sustainability 2022年第1期3卷 82-94页

作者： JIANG Xiaorong LIU Qing WANG Shenglan College of Resource Environment and Tourism Hubei University of Arts and ScienceXiangyang441053China School of Geography and Planning Sun Yat-Sen UniversityGuangzhou510006China

The production and trade of primary products had a growing impact on the economic security of all countries and regions,and the strategic position of these products in the global trade network was becoming increasingly prominent.Based on complex network theory,this paper explored the spatial pattern and complex structural evolution of the global primary product trade network(GPPTN)during 1985-2015 by using index methods,such as centrality,Sankey diagram,and structure entropy,focusing on the diversified spatial structure of China’s import and export markets for primary products(with exceptions of Taiwan of China,Hong Kong of China,and Macao of China due to a lack of data)and their geographical implications for China’s energy security.The research offered the following key findings.The GPPTN showed an obvious spatial heterogeneity pattern,and the area of import consumption was more concentrated;however,the overall trend was decentralized.The trade center of gravity shifted eastwards and reflected the rise of emerging markets.The overall flow of the GPPTN was from west to east and from south to north.In terms of the community detection of the GPPTN,North America,Europe,and Asia increasingly presented an unbalanced“tripartite confrontation”.China’s exports of primary products were mainly concentrated in the Association of Southeast Asian Nations(ASEAN)and other peripheral regions of Asia,and its imports undergone a major transformation,gradually expanding from the peripheral regions of Asia to Africa,the Middle East,Latin America,and other parts of the world.Energy fuels also became the largest imported primary products.Based on the changing trend of structural entropy and main market share,the analysis showed that the stable supply of China’s energy diversification was gradually realized.In particular,the cooperation dividend proposed by the Belt and Road initiative became an important turning point and a strong support for the expansion of China’s energy market diversification pattern and guarantee of energy securi

关键词： Primary products Global trade networks Structure entropy Energy security Import and export market

Cosmogenic^(10)Be dating of the oldest moraine in the Hengduan Mountains

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Science China Earth Sciences 2023年第10期66卷 2211-2223页

作者： Zhigang ZHANG Jiahong ZHENG Haitao CUI Zhijun ZHAO Xinggong KONG Chaogang ZHENG Hong ZHANG Fei GUO Zhiyang CHANG Xue YUAN Mingyang YAN Jie ZHANG Jian WANG School of Geography Nanjing Normal UniversityNanjing210023China Key Laboratory of Virtual Geographic environment(Nanjing Normal University) Ministry of EducationNanjing210023China Jiangsu Center for Collaborative Innovation in Geographical Information resource Development and Application Nanjing210023China tourism and Social Administration college NanJing XiaoZhuang UniversityNangjing211171China

The Hengduan Mountains is in the transitional zone between the Qinghai-Tibet Plateau(QTP)and the YunnanGuizhou Plateau in China,and a key area for elucidating the Quaternary environmental changes in Asia.The paleo-Daocheng ice cap was located on the Shaluli Hilly Plateau in the northeastern Hengduan Mountains,the oldest moraines in the Hengduan Mountains region were found in the ice cap area.Such glacial landforms provide key evidence to study the timing when this area entered the cryosphere with the uplift of the QTP.However,it is difficult to collect suitable glacial boulders from these moraines for traditional terrestrial in-situ cosmogenic nuclide(TCN)exposure dating because of long-term severe moraine degradation.Here,we collected clast samples from the moraine surface and depth profile to constrain the age of the oldest moraine in Kuzhaori(moraine E)using TCN^(10)Be dating technique.The minimum^(10)Be ages of five clast samples from the moraine surface range from 187.4±1.5 to 576.8±4.3 ka,implying that the moraine has been seriously degraded since deposition.Based on the TCN^(10)Be concentrations of the samples from a depth profile and simulations,the exposure-erosion-inheritance history of the profile was obtained.By fitting to the profile^(10)Be concentrations using the chi-square test,the simulations yielded a reliable age of 626.0±52.5 ka for the moraine.Therefore,the oldest moraine(moraine E)in Kuzhaori was most likely formed at about 0.63Ma ago,corresponding to the marine isotope stage(MIS)16.This glaciation represents the maximum Quaternary glaciation after the QTP was elevated into the cryosphere by the Kunlun-Yellow River Tectonic Movement.

关键词： Hengduan Mountains Paleo-Daocheng ice cap Terrestrial in-situ cosmogenic nuclide^(10)Be Depth profile Exposure dating

Soil enzyme activities and their indication for fertility of urban forest soil

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Frontiers of environmental Science & Engineering 2008年第2期2卷 218-223页

作者： Qihua SHAN Yuanchun YU Jian YU Jinchi ZHANG college of Forest resource and environment Nanjing Forestry UniversityNanjing 210037China college of Territorial resources and tourism Anhui Normal UniversityWuhu 241000China

To reveal the biological characteristics of urban forest soil and the effects of soil enzyme on soil fertility as well as the correlation between physicochemical properties and enzyme activities,44 urban forest soil profiles in Nanjing were investigated.Basic soil physicochemical properties and enzyme activities were analyzed in the laboratory.Hydrogen peroxidase,dehydrogenase,alkaline phosphatase,and cellulase were determined by potassium permanganate titration,TTC(C_(19)H_(15)N_(4)·Cl)colorimetry,phenyl phosphate dinatrium colorimetry,and anthrone colorimetry,respectively.The result showed that soil pH,organic carbon(C),and total nitrogen(N)had great effects on hydrogen peroxidase,dehydrogenase,and alkaline phosphatase activities in 0–20 cm thick soil.However,pH only had great effect on hydrogen peroxidase,dehydrogenase,and alkaline phosphatase activities in 20–40 cm thick soil.Hydrogen peroxidase,dehydrogenase,and alkaline phosphatase were important biological indicators for the fertility of urban forest soil.Both in 0–20 cmand 20–40 cmsoil,soil enzyme system(hydrogen peroxidase,dehydrogenase,alkaline phosphatase,and cellulase)had a close relationship with a combination of physicochemical indicators pH,organic C,total N,available K,available P,cation exchange capacity(CEC),and microbial biomass carbon(C_(mic)).The more soil enzyme activities there were,the higher the fertility of urban forest soil.

关键词： urban forest soil enzyme activities soil fertility correlation analysis Nanjing

北京市不同功能区不透水地表时空变化差异分析（英文）

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Journal of Geographical Sciences 2018年第5期28卷 669-684页

作者：乔琨朱文泉胡德勇郝明陈姗姗曹诗颂 State Key Laboratory of Earth Surface Processes and resource Ecology Beijing Normal University Institute of Remote Sensing Science and Engineering Faculty of Geographical Science Beijing Normal University College of Resource Environment and Tourism Capital Normal University Nuclear Industry of China Geotechnical Engineering Co.Ltd Shijiazhuang

Impervious surface(IS) is often recognized as the indicator of urban environmental changes. Numerous research efforts have been devoted to studying its spatio-temporal dynamics and ecological effects, especially for the IS in Beijing metropolitan region. However, most previous studies primarily considered the Beijing metropolitan region as a whole without considering the differences and heterogeneity among the function zones. In this study, the subpixel impervious surface results in Beijing within a time series(1991, 2001, 2005, 2011 and 2015) were extracted by means of the classification and regression tree(CART) model combined with change detection models. Then based on the method of standard deviation ellipse, Lorenz curve, contribution index(CI) and landscape metrics, the spatio-temporal dynamics and variations of IS(1991, 2001, 2011 and 2015) in different function zones and districts were analyzed. It is found that the total area of impervious surface in Beijing increased dramatically during the study period, increasing about 144.18%. The deflection angle of major axis of standard deviation ellipse decreased from 47.15° to 38.82°, indicating the major development axis in Beijing gradually moved from northeast-southwest to north-south. Moreover, the heterogeneity of impervious surface’s distribution among 16 districts weakened gradually, but the CI values and landscape metrics in four function zones differed greatly. The urban function extended zone(UFEZ), the main source of the growth of IS in Beijing, had the highest CI values. Its lowest CI value was 1.79 that is still much higher than the highest CI value in other function zones. The core function zone(CFZ), the traditional aggregation zone of impervious surface, had the highest contagion index(CONTAG) values, but it contributed less than UFEZ due to its small area. The CI value of the new urban developed zone(NUDZ) increased rapidly, and it increased from negative to positive and multiplied, becoming animportant contributor to the rise of urban imperviou

关键词： impervious surface landscape metrics classification and regression tree(CART) function zones Lorenz curve contribution index

Influence of Operating Conditions on the Removal Cd Ions from Aqueous Media by Adsorption Using Chlamydomonas Reinhardtii

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Chinese Journal of Population,resources and environment 2010年第2期8卷 93-96页

作者： Jiang Yongbin Zhu Yi Ji Hongbing resource Environmental and GIS Key Laboratory of Beijing City College of Resource Environment and Tourism Capital Normal University Beijing 100048 China college of Food Science and Nutritional Engineering China Agriculture University Beijing 100083 China

Chlamydomonas reinhardtii(C.reinhardtii) was used to study adsorption of cadmium(Cd) from aqueous media within various experimental conditions.Results showed that the adsorption process was very fast,with most of the adsorption occurring within 30 min of contact time and the equilibrium state was reached in about 60 min.The adsorption ability of the algae increases with the increasing adsorptions sites on cells.Maximum adsorption was observed at the initial Cd concentration of 100 mg/L and pH 6.0. The adsorption was markedly inhibited in the presence of calcium and magnesium ions at 10 mM and the Cd removal efficiency was reduced by 16.54%and 14.99%respectively.This study would be a finding of note with regard to practical wastewater treatment.

关键词：吸附过程莱茵衣藻镉离子运行条件水介质镉(Cd) 实验条件平衡状态

Quantitative exploration of the mechanisms behind the urban thermal environment in Beijing

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Progress in Natural Science:Materials International 2009年第12期19卷 1757-1763页

作者： Dan Meng,Xiaojuan Li~*,Wenji Zhao,Huili Gong Key Laboratory of 3D Information Acquisition and Application,Ministry of Education,Key Laboratory of resource,environment and GIS in Beijing,college of resources environment and tourism,Capital Normal University,Beijing 100048,China Key Laboratory of 3D Information Acquisition and Application Ministry of Education Key Laboratory of Resource Environment and GIS in Beijing College of Resources Environment and Tourism Capital Normal University Beijing 100048 China

The driving mechanism behind the formation of urban thermal environments is the result of a combination of factors.Beijing was chosen as the study area,and the technique of principal component analysis(PCA) was used.A spatial regression method was also applied for quantitative explanation of the thermal mechanism.Multiple Landsat thematic mapper images were used to quantify potential causing factors.Considering the eigenvalues of each factor and its relationship with land surface temperature,the first three principal components(PCs) are regarded as the main causative factors explaining the mechanism as independent variables.The first three PCs mainly reflect urban construction,road density and the normalized difference vegetation index(NDVI),respectively.Ordinary least squares,spatial lag and spatial error regression models were established separately for the relationships between the first three PCs and land surface temperature(LST).In the two spatial regression models,z-statistics for both the spatial lag parameter(ρ) and spatial residual parameter(λ) are significant,indicating the necessity of using spatial regression to replace the OLS regression model,as well as indicating that the spatial error regression model is superior to the spatial lag regression model.Overall,the normalized difference built-up index(NDBI) and road density are the most significant positive contributions to LST.

关键词： Urban thermal environment Drive mechanism Spatial regression Beijing

Analyzing land use characteristics of rural settlements on the urban fringe of Liangjiang New Area, Chongqing, China

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Journal of Mountain Science 2016年第10期13卷 1855-1866页

作者： WANG Yi BI Guo-hua YANG Qing-yuan WANG Zhao-lin college of resources and environment Southwest University School of Geographical Sciences Southwest University School of tourism and Land resource Chongqing Technology and Business University

The objective of this paper is to analyze land use characteristics of rural settlements in urban fringe so as to provide references for optimizing the regional distribution of rural settlements, consolidating rural settlements, and coordinating urban-rural integrated development. The methods of spatial statistical analysis, buffer analysis, Ripley's K function, kernel density analysis based on GIS(Geographic Information System) were used to analyze the characteristics of scale, spatial differentiation and spatial patterns of the rural settlements in Liangjiang New Area in Chongqing Municipality of China. The fractal dimension formula was also developed to reflect fractal feature of the rural settlements. The results show that, the scale of rural settlements in Liangjang New Area takes on distinct characteristics of spatial differentiation along with changes in elevation, gradient, location, geohazards distribution, and the like. The fractal characteristic of rural settlements has obvious regional variations subject to the 6 factors of location in the Liangjiang New Area. Overall, the worse the terrain conditions are, the larger the fractal dimension values become. The better the locationconditions, the larger the fractal dimension values are. The spatial pattern in the township scale presents three kinds of distribution as being aggregated, uniform and random. In contract, the spatial pattern in the plaque scale displays a banding distribution from a general view with several aggregation zones centering on each town center. From the results, we can see that the characteristics of rural settlements in urban fringe are more complicated. For such kind of rural settlements in special regions, in the rural land consolidation more attention should be paid to improve the rural living environments and public services, as well as to promote the harmonious relationship between the urban and rural areas.

关键词： Land use Rural settlements Land-use characteristics Urban fringe Chongqing Liangjiang New Area

Chemisorption and Physical Adsorption Roles in Cadmium Biosorption by Chlamydomonas Reinhardtii

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Chinese Journal of Population,resources and environment 2010年第3期8卷 54-58页

作者： Jiang Yongbin Huo Xiangyuan Zhu Yi Ji Hongbing resource Environmental and GIS Key Laboratory of Beijing City College of Resource Environment and Tourism Capital Normal University Beijing 100048 China college of Food Science and Nutritional Engineering China Agriculture University Beijing 100083 China

The aim of this study was to investigate the mechanism of cadmium (Cd) adsorbed by microalgae Chlamydomonas reinhardtii (C.reinhardtii). The kinetic and adsorption isotherm of the process could be well described by mathematical models. Chemical modification experiments and Fourier transform infrared spectra indicated that carboxyl and amine groups were the important functional groups for adsorption of Cd. The maximum contribution of physical adsorption in the overall adsorption process was evaluated as 5.5%. These results indicated that chemisorption was the dominating mechanism of Cd biosorption by C.reinhardtii.

关键词：镉(Cd) 化学吸附吸附作用物理吸附衣藻傅里叶变换红外光谱吸附等温线数学模型