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Establishing environmental background values of selected trace elements and environmental quality assessment of fi negrained sediments in the Jiaozhou Bay catchment,China
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作者 Fangjian XU Xu TIAN +2 位作者 Xianchao WANG Xiaoming WAN Bo CHEN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第4期1444-1453,共10页
With the development of economy,the impact of human activities on ecological environment is increasing,and environmental protection work is important.Trace elements(Co,Ni,Cu,Pb,Zn,Cd,Cr,and Sc)in surface fi ne-grained... With the development of economy,the impact of human activities on ecological environment is increasing,and environmental protection work is important.Trace elements(Co,Ni,Cu,Pb,Zn,Cd,Cr,and Sc)in surface fi ne-grained sediment samples from the Jiaozhou Bay catchment were selected to evaluate their 2015 environmental background values and the environmental quality.Using statistical analysis,the environmental background values(ranges)of Sc,Co,Ni,Cu,Pb,Zn,Cd,and Cr were calculated,being 13.1(10.8-15.4),12.4(8.6-16.2),32.0(22.9-41.2),29.6(13.5-64.9),24.1(13.0-44.6),77.6(38.5-156.5),0.07(0.02-0.20),and 82.5(66.5-104.0)mg/kg,respectively.The enrichment factor,contamination factor,and pollution load index were used to evaluate the pollution status of the Jiaozhou Bay catchment.The environmental background values of most elements are higher than those of the upper continental crust and lower than those of global shale.At present,the pollution in the eastern Jiaozhou Bay is much higher than that in the western part.The results shall be helpful for future management for trace element pollution monitoring in the Jiaozhou Bay catchment. 展开更多
关键词 SEDIMENTS environmental background values environmental assessment CONTAMINATION Jiaozhou Bay
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Soil Geochemical Background Value and Environmental Quality Assessment in Jinan City
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作者 Hongjin WANG Chao YU +1 位作者 Wenkai REN Yan GUO 《Agricultural Biotechnology》 CAS 2022年第5期72-75,79,共5页
[Objectives]This study was conducted to accurately assess soil and environmental quality in Jinan City. [Methods] Based on the multipurpose regional geochemical survey data of 1∶250 000 in Shandong Province, the diff... [Objectives]This study was conducted to accurately assess soil and environmental quality in Jinan City. [Methods] Based on the multipurpose regional geochemical survey data of 1∶250 000 in Shandong Province, the differences between the soil geochemical background values of 54 indexes in Jinan City and the soil in the whole province and the comprehensive geochemical class of soil quality were studied. [Results] The contents of C and Cao in Jinan soil was significantly higher than the background values of Shandong Province. The Cd, Cr, Cu, F, Ni, Sn, MgO, Cao and Na_(2)O contents and pH value were higher than the abundance of the A soil layer in China, but the nutrient index contents of Se, I and OrgC were lower than the national background values. The surface soil quality in the study area was generally good, with the sum of superior, good and medium accounting for 99.76% of the total area of the study area. The distribution area of poor soil was the least, accounting for only 0.24%, and it was scattered near industrial and mining enterprises in the urban area of Jinan City, Laiwu District, Gangcheng District and Zhangqiu District, which was closely related to human activities. [Conclusions] This study has practical guiding significance for improving land use efficiency. 展开更多
关键词 Surface soil background value GEOCHEMISTRY Land quality Assessment Jinan city
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Non-equal-interval direct optimizing Verhulst model that x(n) be taken as initial value and its application 被引量:2
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作者 Luo, Youxin Chen, Mianyun +1 位作者 Che, Xiaoyi He, Zheming 《Journal of Southeast University(English Edition)》 EI CAS 2008年第S1期17-21,共5页
To overcome the deficiencies of the existing Verhulst GM(1,1) model, based on the existing grey theory, a non-equal-interval direct optimum Verhulst GM(1,1) model is built which chooses a modified n-th component x(n) ... To overcome the deficiencies of the existing Verhulst GM(1,1) model, based on the existing grey theory, a non-equal-interval direct optimum Verhulst GM(1,1) model is built which chooses a modified n-th component x(n) of X(0) as the starting condition of the grey differential model. It optimizes a modified β value and the background value, and takes two times fitting optimization. The new model extends equal intervals to non-equal-intervals and is suitable for general data modelling and estimating parameters of the direct Verhulst GM(1,1). The new model does not need to pre-process the primitive data, nor accumulate generating operation (AGO) and inverse accumulated generating operation (IAGO). It is not only suitable for equal interval data modelling, but also for non-equal interval data modelling. As the new information is fully used and two times fitting optimization is taken, the fitting accuracy is the highest in all existing models. The example shows that the new model is simple and practical. The new model is worth expanding on and applying in data processing or on-line monitoring for tests, social sciences and other engineering sciences. 展开更多
关键词 grey system data processing Verhulst GM(1 1) non-equal interval direct modelling OPTIMUM background value two times fitting
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Improvement and application of GM(1,1) model based on multivariable dynamic optimization 被引量:12
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作者 WANG Yuhong LU Jie 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第3期593-601,共9页
For the classical GM(1,1)model,the prediction accuracy is not high,and the optimization of the initial and background values is one-sided.In this paper,the Lagrange mean value theorem is used to construct the backgrou... For the classical GM(1,1)model,the prediction accuracy is not high,and the optimization of the initial and background values is one-sided.In this paper,the Lagrange mean value theorem is used to construct the background value as a variable related to k.At the same time,the initial value is set as a variable,and the corresponding optimal parameter and the time response formula are determined according to the minimum value of mean relative error(MRE).Combined with the domestic natural gas annual consumption data,the classical model and the improved GM(1,1)model are applied to the calculation and error comparison respectively.It proves that the improved model is better than any other models. 展开更多
关键词 grey prediction GM(1 1)model background value grey system theory
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Main progress and prospect for China’s hydrogeological survey 被引量:4
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作者 WU Ai-min HAO Ai-bing +6 位作者 GUO Hai-peng LIU Jing-tao ZHANG Er-yong WANG Huang WANG Xin-feng WEN Xue-ru ZHANG Cui-guang 《Journal of Groundwater Science and Engineering》 2020年第3期195-209,共15页
This paper reviewed the main achievements of hydrogeological survey in China,summarized the significant progress of hydrogeological survey over the past decade,and forecasted the key responsibilities for hydrogeologic... This paper reviewed the main achievements of hydrogeological survey in China,summarized the significant progress of hydrogeological survey over the past decade,and forecasted the key responsibilities for hydrogeological survey in the“14th Five-year Plan”.The significant progress includes:China established the 1:50000 standard hydrogeological survey system with Chinese characteristics and produced the new generation of highquality hydrogeological maps;the national groundwater monitoring project was completed and accepted,which marks China taking the leading position in groundwater monitoring internationally;fruitful results were achieved in the national groundwater quality survey,and groundwater quality background values were basically identified and checked;hydrogeological and environmental geological survey was continuously promoted in karst areas and the ecological restoration of rocky desertification achieved remarkable results;China strengthened layer exploration techniques for groundwater,integrating the key and practical techniques of layer exploration and monitoring;the exploration of groundwater in the poverty-stricken regions and old revolutionary base areas were effectively promoted to strongly guarantee the poverty alleviation and drinking water safety;the mystery of desert groundwater was uncovered,making up for the shortage of 1:250000 hydrogeological survey in the Badain Jaran Desert;and more efforts were made to conduct survey on the water resources in the basin,and to finish the unified measurement of national-scale groundwater level. 展开更多
关键词 Hydrogeological survey National Groundwater Monitoring Project Groundwater quality background values Ecological restoration of rocky desertification China
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Application of Environmental Geophysical Prospecting in Environmental Quality Investigation of Reclaimed Land
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作者 Taicong CHEN Hong WU +1 位作者 Haifeng HUANG Ruirui SUN 《Meteorological and Environmental Research》 CAS 2020年第3期81-85,共5页
Traditional geophysical prospecting methods( electromagnetic induction method,high-density resistivity method and ground penetrating radar method) were applied to the environmental quality detection of reclaimed land ... Traditional geophysical prospecting methods( electromagnetic induction method,high-density resistivity method and ground penetrating radar method) were applied to the environmental quality detection of reclaimed land in the "198" area of Shanghai. According to the results of drilling sampling and laboratory analysis,the accuracy,suitability and consistency of theses geophysical prospecting methods were evaluated. 展开更多
关键词 "198"area Reclaimed land Geophysical prospecting method background value
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