91人妻人人澡人人爽人人DVD|日韩激情天堂国产av综合网|91国产1区av天堂网|一级国产A片AV无码网站|爱综合偷排网国产成人片|日韩高免费五码视频|欧美黄色A级片|a毛三级久久99|深夜无码激情人妻黄片看黄片|A片成人免费视频网站

Assessment on the pollution of nitro

時(shí)間:2023-04-25 20:11:47 環(huán)境保護(hù)論文 我要投稿
  • 相關(guān)推薦

Assessment on the pollution of nitrogen and phosphorus of Beijing surface water based on GIS system and multivariate sta

Abstract: This paper presented the characteristics of nitrogen and phosphorus pollution in Beijing surface water during the survey. A significant difference was found out in concentration distribution of various parameters of nitrogen and phosphorus. Most water bodies in five water systems were polluted by total nitrogen with the content even up to 120 mg/L which was higher than exceeded the fifth class standard of national surface water quality standard GB3838-2002 except for several segments of Chaobaihe and Yongdinghe. Ammonia and phosphorus showed a similar tendency of distribution with higher content in Daqinghe, Beiyunhe and Jiyunhe water systems, but with relatively low concentrations in Chaobaihe and Yongdinghe water systems. Meanwhile, nitrate was found at comparatively low content(mostly less than 10 mg/L) and could fit for corresponding water quality requirements. Totally, the water quality of Daqinghe, Jiyunhe and Beiyunhe river systems as well as the lower reaches of Yongdinghe and Chaobaihe was contaminated seriously with high content of total nitrogen and phosphorus. Through multivariate statistical approaches, it can be concluded that total nitrogen, ammonia and total phosphorus was highly correlated to chemical oxygen demand, biochemical oxygen demand, dissolved oxygen and electrical conductivity, which explained the same pollution source from anthropogenic activities. 作 者: LI Lian-fang    LI Guo-xue    LIAO Xiao-yong   作者單位: LI Lian-fang,LI Guo-xue(College of Resources and Environmental Sciences, Chinese Agricultural University, Beijing 100094, China)

LIAO Xiao-yong(Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China) 

期 刊: 環(huán)境科學(xué)學(xué)報(bào)(英文版)  ISTICSCI   Journal: JOURNAL OF ENVIRONMENTAL SCIENCES  年,卷(期): 2004, 16(6)  分類號: X131 X192  Keywords: surface water    nitrogen    phosphorus    assessment    GIS   

【Assessment on the pollution of nitro】相關(guān)文章:

pollution英語作文帶翻譯04-07

保護(hù)環(huán)境的英語作文White Pollution04-25

白色污染W(wǎng)hite Pollution英語四級作文(精選23篇)01-06

初中英語作文:減少白色污染 Reduce White Pollution(通用24篇)12-21