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Environmental significance and hydrochemical characteristics of rivers in the western region of the Altay Mountains,China
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作者 LIU Shuangshuang WANG Feiteng +2 位作者 XU Chunhai WANG Lin LI Huilin 《Journal of Arid Land》 SCIE CSCD 2023年第9期1052-1066,共15页
Analysis of environmental significance and hydrochemical characteristics of river water in mountainous regions is vital for ensuring water security.In this study,we collected a total of 164 water samples in the wester... Analysis of environmental significance and hydrochemical characteristics of river water in mountainous regions is vital for ensuring water security.In this study,we collected a total of 164 water samples in the western region of the Altay Mountains,China,in 2021.We used principal component analysis and enrichment factor analysis to examine the chemical properties and spatiotemporal variations of major ions(including F-,Cl-,NO_(3)-,SO_(4)^(2-),Li+,Na+,NH4+,K+,Mg^(2+),and Ca^(2+))present in river water,as well as to identify the factors influencing these variations.Additionally,we assessed the suitability of river water for drinking and irrigation purposes based on the total dissolved solids,soluble sodium percentage,sodium adsorption ratio,and total hardness.Results revealed that river water had an alkaline aquatic environment with a mean pH value of 8.00.The mean ion concentration was ranked as follows:Ca^(2+)>SO_(4)^(2-)>Na+>NO_(3)->Mg^(2+)>K+>Cl->F->NH_(4)+>Li+.Ca^(2+),SO_(4)^(2-),Na+,and NO_(3)-occupied 83%of the total ion concentration.In addition,compared with other seasons,the spatial variation of the ion concentration in spring was obvious.An analysis of the sources of major ions revealed that these ions originated mainly from carbonate dissolution and silicate weathering.The recharge impact of precipitation and snowmelt merely influenced the concentration of Cl-,NO_(3)-,SO_(4)^(2-),Ca^(2+),and Na+.Overall,river water was in pristine condition in terms of quality and was suitable for both irrigation and drinking.This study provides a scientific basis for sustainable management of water quality in rivers of the Altay Mountains. 展开更多
关键词 environmental significance hydrochemical characteristics water quality soluble sodium percentage(SSP) ion concentration Altay Mountains
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Reform of Carbonate Rock Subsurface by Crustose Lichens and Its Environmental Significance 被引量:10
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作者 CAO Jianhua and WANG FuxingInstitute of Karst Geology, Chinese Academy of Geological Sciences, Guilin, Guanxi 541004 Xiao Pinfang Liu Xinzhu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1998年第1期94-99,共6页
Crustose lichens are distributed extensively in karst areas in Southern China. They can be found on the surface of carbonate rocks. Through biophysical and biochemical processes, crustose lichens reform the subsurface... Crustose lichens are distributed extensively in karst areas in Southern China. They can be found on the surface of carbonate rocks. Through biophysical and biochemical processes, crustose lichens reform the subsurface of carbonate rocks and in the meanwhile change their physical and chemical properties: (1) the mechanical strength decreases by 17.04° on average (up to 33.2°); (2) the chemical solution surface area increases from 28.26% to 75.36% (lichen microholes considered only); and (3) the water-holding capacity is greatly improved. Comparative field experiments between biokarst samples underneath crustose lichens and fresh rock samples with the same composition and texture show that the corrosional rate of carbonate rocks of the former is 1.264–1.643 times higher than that of the latter. Crustose lichens are considered as an activator of the surface corrosion of carbonate rocks. 展开更多
关键词 crustose lichen carbonate rock biokarst CORROSION environmental significance
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Geochemical records of phosphorus in Jiaozhou Bay sediments—Impli-cations for environmental changes in recent hundred years 被引量:8
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作者 DAI Jicui SONG Jinming +3 位作者 LI Xuegang YUAN Huamao ZHENG Guoxia LI Ning 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2007年第4期132-147,共16页
Phosphorus is a key element and plays an important role in global biogeochemical cycles. The evolution of sedimentary environment is also influenced by phosphorus concentrations and fractions as well as phosphate sorp... Phosphorus is a key element and plays an important role in global biogeochemical cycles. The evolution of sedimentary environment is also influenced by phosphorus concentrations and fractions as well as phosphate sorption characteristics of the marine sediments. The geochemical characteristics of phosphorus and their environmental records were presented in Jiaozhou Bay sediments. Profiles of different forms of phosphorus were measured as well as the roles and vertical distributions of phosphorus forms in response to sedimentary environment changes were investigated. The results showed that inorganic phosphorus (IP) was the major fraction of total phosphorus (TP); phosphorus which is bound to calcium, iron and occluded phosphorus, as well as the exchangeable phosphorus were the main forms of IP, especially calcium - phosphorus, including detrital carbonate-bound phosphorus (Det- P) and authigenic apatite-bound phosphorus (ACa- P), are the uppermost constituent of IP in Jiaozhou Bay sediments. Moreover, the lead-210 chronology technology was employed to estimate how much phosphorus was buried ultimately in sediments. And the research showed that the impacts of human activities have increased remarkably in recent years especially between the 1980s and 2000. According to research, the development of Jiaozhou Bay environment in the past hundred years can be divided into three stages : ( 1 ) before the 1980s characterized by the relatively low sedimentation rate, weak land-derived phosphorus inputs and low anthropogenic impacts; (2) from the 1980s to around 2000, accelerating in the 1990s, during which high sedimentation rates, high phosphorus abundance and burial fluxes due to the severe human activities impacted on the whole environmental system ; ( 3 ) after 2000, the period of the improvement of environment, the whole system has been improved including the decreasing sedimentation rates, concentration and the burial fluxes of phosphorus. 展开更多
关键词 phosphorus forms geochemical characteristics anthropogenic activity environmental significance Jiaozhou Bay sediments
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Experimental Study on Formation Conditions of Ammoniojarosite and Its Environmental Significance 被引量:7
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作者 WANG Changqiu MA Shengfeng +1 位作者 LU Anhuai ZHOU Jiangong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第2期296-301,共6页
Formation conditions of ammoniojarosite in system Fe2(SO4)3-(NH4)2SO4-H2O are investigated in this paper. The results show that ammoniojarosite can be formed rapidly under normal temperature and pressure by contro... Formation conditions of ammoniojarosite in system Fe2(SO4)3-(NH4)2SO4-H2O are investigated in this paper. The results show that ammoniojarosite can be formed rapidly under normal temperature and pressure by controlling suitable pH value and Fe2(SO4)3 and (NH4)2SO4 concentrations. The pH value, temperature and concentration of Fe2(SO4)3 medium are key factors influencing the formation of ammoniojarosite. Under normal temperature, precipitation of ammoniojarosite can be seen within 24 hours at pH values between 2.6-3.1, and a great quantity of ammoniojarosite is formed within 48 hours. At about 90℃, the pH value range forming ammoniojarosite extends to 1.2-3.1, and within this range the rise of pH value is advantageous to the formation of ammoniojarosite and high Fe2(SO4)3 concentration is also advantageous. Relative pure ammoniojarosite is synthesized under high Fe2(SO4)3 concentration (≥0.05 M) and ammoniojarosite containing melanterite and colloid amorphous hydroxide vitriol iron is formed at low Fe2(SO4)3 concentration. The deposition process of ammoniojarosite can be used to harness wastewater from mines and other industries and remove S, Fe and other toxic and harmful elements, such as As, Cr, Hg, Pb in water. Rapid formation of ammoniojarosite and other jarosite analogs under normal temperature and pressure has a good potential prospect for harnessing acid wastewater by means of precipitation of jarosite and its analogs. 展开更多
关键词 ammoniojarosite formation conditions harness of acid wastewater environmental significance
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Experimental Study on Treatment of High-concentrated Sulfur Wastewater by Process of Depositing Natrojarosite and Its Environmental Significance 被引量:3
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作者 MA Shengfeng WANG Changqiu +2 位作者 LU Anhuai GUO Yanjun HE Hongliao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第2期330-334,共5页
High-concentrated sulfur wastewater with sodium and COD (chemical oxygen demand) up to 26000 mg/L from a chemical plant, Jiangsu Province of China has been treated by deposition of natrojarosite in lab. The results ... High-concentrated sulfur wastewater with sodium and COD (chemical oxygen demand) up to 26000 mg/L from a chemical plant, Jiangsu Province of China has been treated by deposition of natrojarosite in lab. The results indicated that the COD of the wastewater was decreased sharply from 26000 mg/L to 1001 mg/L, with removal rate of COD up to 96% by twice precipitations of natrojarosite and twice oxidation of H202. The treated sulfur wastewater reached the requirement of subsequent biochemical treatment to water quality. The optimal operational parameters should be controlled on pH value between 2.50 and 3.20 and 50 g FeCly6H2O solid added in per liter wastewater. The study provided an experimental basis for pretreatment of high-concentrated sulfur wastewater and proposed a new mineralogical method on treatment of other wastewaters. Depositing process of jarosite and its analogs should be able to be used to treat wastewater from mine and other industries to remove S, Fe and other toxic and harmful elements, such as As, Cr, Hg, Pb, etc. in the water. 展开更多
关键词 natrojarosite high-concentrated sulfur wastewater COD environmental significance
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Distributions of surface sediments surrounding the Antarctic Peninsula and its environmental significance 被引量:1
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作者 WANG Chunjuan CHEN Zhihua +3 位作者 LI Chunshun DU Dewen YAN Shijuan ZHU Zhiwei 《Advances in Polar Science》 2014年第3期164-174,共11页
We analyzed grain size composition to provide information on the types and distributions as well as depositional varieties of marine surface sediments from the area surrounding the Antarctic Peninsula. The samples ret... We analyzed grain size composition to provide information on the types and distributions as well as depositional varieties of marine surface sediments from the area surrounding the Antarctic Peninsula. The samples retrieved from the study area contain gravel, sand, silt and clay. As suggested by bathymetry and morphology, the study area is characterized by neritic, hemipelagic and pelagic deposits. The glacial-marine sediments can be divided into two types, residual paratill and compound paratill, which are primarily transported by glaciers and as ice-rafted debris. Ocean current effects on deposition are more obvious, and the deposit types are distributed consistently with terrain variations. 展开更多
关键词 Antarctic Peninsula surface sediments grain size environmental significance
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Environmental Occurrence of Selenium in Waters and Related Health Significance 被引量:1
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作者 JANE L. VALENTINE(School of Public Health, University of CalIfornia at Los Angeles, Los Angeles, CA 90024, USA) 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1997年第2期292-299,共8页
Appreciable amounts of selenium in spring and well waters can be found due to geological occurrence. Concentrations of as much as 400 9000 μg/l have been reported in U. S. waters.These levels are 8 to 180 times the c... Appreciable amounts of selenium in spring and well waters can be found due to geological occurrence. Concentrations of as much as 400 9000 μg/l have been reported in U. S. waters.These levels are 8 to 180 times the current EPA drinking water standard and approximate dietary exposures of 4900μg in selenosis regions of China. Reviews of health significance of the elevated drinking water exposures to U. S. populations revealed elevated concentrations of selenium in urine and blood. A decrease in glutathione peroxidase activity in such instances was noted. However noticeable symptoms and signs seem absent in studies reviewed. A comparison of intake levels (diet or drinking water) to urinary excretion for residents of China and the U. S. produced a correlation coefficient, r = 0. 82 (P < 0. 01 ) for the three research studies available 展开更多
关键词 In AM environmental Occurrence of Selenium in Waters and Related Health Significance
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Age and height of last highest lake levels on theTibetan Plateau and their enveironmentalsignificance
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作者 LI Bing-yuan, ZHU Li-ping(Institute of Geography, Chinese Academy of Sciences, Beijing 100101, China) 《Journal of Geographical Sciences》 SCIE CSCD 1999年第4期326-334,共9页
The fluctuation of lake levels in Tibetan area may be well reflected by the landformevidences, especially the last highest lake levels. This, in a certain degree, is more suitable fordetermning the climatic humidity a... The fluctuation of lake levels in Tibetan area may be well reflected by the landformevidences, especially the last highest lake levels. This, in a certain degree, is more suitable fordetermning the climatic humidity and aridity in macro scale compared with many other indicatorswhich are also sensitive to the sedimentary environmental change. According to the analyses of thelakes such as Tianshuihai Lake, Bangdag Co, Lungmu Co, Bangong Co, Serfing Co, Chabyer Caka,Qahan salt lake, Qinghai lake, the lake group in north-east Qiangtang and the lake group in southTibet. the authors thought that the lakes on the Tibetan Plateau generally appeared the high lakelevel during 40-25 ka BP. The plenty of water quantity may represent a special warm-humid stage inTibet area compared with the sub-warm-humid stage reflected by marine oxygen isotope records.Thus, there may existed different driving factors to climatic changes between the high latitUde areasand middle-low latitude mountains. 展开更多
关键词 Paleo lake shore lines age relative height. Tibetan Plateau environmental significance
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SIGNIFICANCE OF THE ENGLISH ENVIRONMENT IN ENGLISH TEACHING
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作者 ELVERNE L.ASBURY 《广州大学学报(社会科学版)》 1995年第2X期61-66,共6页
Although language study can be very interesting, it is admittedly about the most complex type of learning that a student can undertake, it is very important that we realize that language study is different from the st... Although language study can be very interesting, it is admittedly about the most complex type of learning that a student can undertake, it is very important that we realize that language study is different from the study of science or mathematics and is more complex. Therefore the mechanical methods employed in the learning of multiplication tables, for example, may not be he most appropriate methods to use in teaching language. Real ability with language is the ability to communicate ideas. A student may know a lot of sentence patterns and rules of grammar 展开更多
关键词 SIGNIFICANCE OF THE ENGLISH ENVIRONMENT IN ENGLISH TEACHING
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Biogenic silica contents of Lake Qinghai sediments and its environmental significance 被引量:5
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作者 Bin LIU Hai XU +3 位作者 Jianghu LAN Enguo SHENG Shuai CHE Xinying ZHOU 《Frontiers of Earth Science》 SCIE CAS CSCD 2014年第4期573-581,共9页
Changes in the levels ofbiogenic silica (BSi%) in lake sediments have been widely used in order to study lake productivity and palaeoclimatic changes. However, the provenance of biogenic silica (BSi) needs to be i... Changes in the levels ofbiogenic silica (BSi%) in lake sediments have been widely used in order to study lake productivity and palaeoclimatic changes. However, the provenance of biogenic silica (BSi) needs to be investigated for each lake, especially for large lakes, as does the relationship between levels of BSi and relevant environmental factors. In this study, we measured the percentage of BSi contained in lake sediments, river sediments, and surface soils within the Lake Qinghai catchment, and compared the quantities and shapes of diatoms and phytoliths before and after the extraction processes. The results suggest that BSi in lake sediments is primarily derived from endogenous diatoms; therefore, BSi levels can be used to reflect the changes in primary productivity within the lake. Further comparisons showed that on long-term timescales, the variations in BSi% are generally consistent with those in total organic carbon (TOC) and grain size, reflecting the dominant impacts of precipitation on primary productivity in Lake Qinghai. On short-term timescales, however, the relationship between BSi% and TOC and that between BSi% and grain size are not clear or stable. For example, BSi% sometimes covaried with grain size, but it was sometimes out of phase with or even inversely related to grain size. We speculate that both climate and environmental processes, such as the dilution effect, influence short-term BSi% and its related environmental significance. As a result, BSi% should be used selectively as an indicator of climatic changes on different time scales. 展开更多
关键词 biogenic silica environmental significance Lake Qinghai PRECIPITATION
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Significant developments for the Journal of Environmental Sciences in 2014
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作者 Qingcai Feng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第1期I0001-I0001,共1页
First of all, it is my honor to announce that Professor X. Chris Le has been appointed the Editor-in-Chief of Journal of Environmental Sciences (JES) after an international search and selection by the committee memb... First of all, it is my honor to announce that Professor X. Chris Le has been appointed the Editor-in-Chief of Journal of Environmental Sciences (JES) after an international search and selection by the committee members of the Research Center of Eco-environmental Sciences, Chinese Academy of Sciences. Professor Hongxiao Tang, 展开更多
关键词 Significant developments for the Journal of environmental Sciences in 2014
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