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Title: 2-year study of chemical composition of bulk deposition in a South China coastal city: comparison with East Asian cities

Using the emission strengths of the precursor gases, the nature of soil in China, the ventilation power and half value rainout region length, the nss-SO{sub 4}{sup 2-}, NO{sub 3}{sup -}, Ca{sup 2+}, and NH{sub 4}{sup +} concentrations, and pH of rainwater at Hong Kong and other cities of China and Japan are compared and rationalized. The chemical composition of Hong Kong bulk deposition from 1998 to 2000 is taken from the collection and analysis of 156 daily samples. The volume-weighted average (VWA) pH is 4.2 over the whole study period. Nonsea salt- (nss-) sulfate is the most abundant species in the samples, and the pH mostly depended upon the concentrations of the major species nss-SO{sub 4}{sup 2-}, NO{sub 3}{sup -}, Ca{sup 2+}, and NH{sub 4}{sup +}. All species concentrations show higher levels in the cold season (especially NO{sub 3}- and Ca{sup 2+}), which indicates the dominant dilution effects in the warm season due to heavy rainfall and the influence of the continental outflow of pollutants during the cold season. For Hong Kong bulk deposition, the VWA pH is slightly lower in the cold season, and there is a slight decrease in VWA pH over the period from 1994 to 2000.more » The impact of acid rain in Hong Kong is briefly discussed. 36 refs., 3 figs., 5 tabs.« less
Authors:
; ;  [1]
  1. City University of Hong Kong, Hong Kong (China). Department of Biology and Chemistry
Publication Date:
OSTI Identifier:
20674372
Resource Type:
Journal Article
Resource Relation:
Journal Name: Environmental Science and Technology; Journal Volume: 39; Journal Issue: 17; Other Information: bhtan@edu.hk
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; CHINA; URBAN AREAS; SULFATES; NITRATES; PH VALUE; ACID RAIN; RAIN WATER; DEPOSITION; AMMONIA; SEASONAL VARIATIONS; ANNUAL VARIATIONS; ASIA; COMPARATIVE EVALUATIONS; JAPAN; CHEMICAL COMPOSITION; ATMOSPHERIC PRECIPITATIONS; WATER CHEMISTRY; SULFUR DIOXIDE; NITROGEN OXIDES