期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
Environmental significance and hydrochemical characteristics of rivers in the western region of the Altay Mountains,China
1
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
下载PDF
SIGNIFICANCE OF THE ENGLISH ENVIRONMENT IN ENGLISH TEACHING
2
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
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部