Calculation of city total maximum allocated load of total nitrogen for jurisdictions in Qingdao, China: A water quality-based modeling approach

Yan Wang; Dehai Song; Keqiang Li; Ying Su; Shengkang Liang; Yanbin Li; Xiulin Wang

doi:10.1016/j.scitotenv.2018.10.113

Calculation of city total maximum allocated load of total nitrogen for jurisdictions in Qingdao, China: A water quality-based modeling approach

Sci Total Environ. 2019 Feb 20:652:455-470. doi: 10.1016/j.scitotenv.2018.10.113. Epub 2018 Oct 9.

Authors

Yan Wang¹, Dehai Song², Keqiang Li³, Ying Su⁴, Shengkang Liang⁵, Yanbin Li⁵, Xiulin Wang⁵

Affiliations

¹ Key Laboratory of Marine Chemistry Theory and Technology (Ocean University of China), Ministry of Education, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China.
² Key Laboratory of Physical Oceanography, Ministry of Education, Ocean University of China, Qingdao 266100, China; Marine Dynamic Process and Climate Function Laboratory, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China.
³ Key Laboratory of Marine Chemistry Theory and Technology (Ocean University of China), Ministry of Education, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China. Electronic address: likeqiang@ouc.edu.cn.
⁴ Key Laboratory of Marine Chemistry Theory and Technology (Ocean University of China), Ministry of Education, Qingdao 266100, China; Environmental Science and Engineering Department, Ocean University of China, Qingdao 266100, China.
⁵ Key Laboratory of Marine Chemistry Theory and Technology (Ocean University of China), Ministry of Education, Qingdao 266100, China.

PMID: 30368176
DOI: 10.1016/j.scitotenv.2018.10.113

Abstract

This study aims to provide a quantitative basis for the precision emission reduction of land-based total nitrogen (TN) pollutants in Qingdao, China. The total maximum allocated load (TMAL) of TN pollutants within jurisdictions in Qingdao was calculated by using a 3D hydrodynamic-water quality model and a linear programming model. The TMAL includes emission TMAL, point-source and nonpoint source TMAL, TMAL removed by municipal sewage treatment system (MSTS), and soil-retained and water-retained TMAL, which were calculated after the division of source units, establishment of the land-based TN load matrix, simulation of the concentration response matrix, setting of a dissolved inorganic nitrogen (DIN) concentration control standard in the Qingdao coastal area, and calculation of TMAL. In the reliability analysis, a concentration under TMAL was considered to indicate satisfactory water quality criteria (relative standard deviation = 17%, Kappa = 0.55). The results showed that the emission TMAL density of nitrogen pollutants in source units was 1.8 ton/km²/a. Nonpoint and point source-produced TMAL densities were 17.0 ton/km²/a and 5.2 ton/km²/a, respectively. MSTS-removed TMAL density was 12.2 ton/km²/a. Soil- and water-retained TMAL were 4.0 ton/km²/a and 0.7 ton/km²/a, respectively. The summed F_(D)^∗ proportions of 10 districts were, in descending order, Huangdao (22%), Laoshan (21%), Jimo (18%), Shibei (13%), Licang (7%), Pingdu (7%), Jiaozhou (4%), Shinan (3%), Laixi (3%) and Chengyan (2%).

Keywords: Coastal area of Qingdao; Coastal pollution control; Jurisdictions; Total maximum allocated load; Total nitrogen; Water quality.