Evaluation of ammonia and nitrate distribution and reduction within stormwater green infrastructure with different woody plants under multiple influencing factors

Bei Zhang; Liang Chen; Qizhong Guo; Jijian Lian; Ye Yao

doi:10.1016/j.jenvman.2021.114086

Evaluation of ammonia and nitrate distribution and reduction within stormwater green infrastructure with different woody plants under multiple influencing factors

J Environ Manage. 2022 Jan 15;302(Pt B):114086. doi: 10.1016/j.jenvman.2021.114086. Epub 2021 Nov 15.

Authors

Bei Zhang¹, Liang Chen², Qizhong Guo³, Jijian Lian⁴, Ye Yao¹

Affiliations

¹ State Key Laboratory of Hydraulic Engineering Simulation and Safety, Tianjin University, Tianjin, 300072, PR China; School of Civil Engineering, Tianjin University, Tianjin, 300072, PR China.
² State Key Laboratory of Hydraulic Engineering Simulation and Safety, Tianjin University, Tianjin, 300072, PR China; School of Civil Engineering, Tianjin University, Tianjin, 300072, PR China; Yuantaifeng (Baotou) Biotechnology Co., Ltd, Baotou, Inner Mongolia, 014100, PR China. Electronic address: liangchen@tju.edu.cn.
³ Department of Civil and Environmental Engineering, Rutgers University-New Brunswick, Piscataway, NJ, 08854, USA.
⁴ State Key Laboratory of Hydraulic Engineering Simulation and Safety, Tianjin University, Tianjin, 300072, PR China; School of Civil Engineering, Tianjin University, Tianjin, 300072, PR China; School of Water Conservancy and Hydroelectric Power, Hebei University of Engineering, Handan, Hebei, 056038, PR China.

PMID: 34794050
DOI: 10.1016/j.jenvman.2021.114086

Abstract

The impact of stormwater green infrastructures (GIs) with different woody plants on nitrogen (N) distribution is still poorly understood. Laboratory experiments were conducted for GIs without or with Sophora japonica and Malus baccata to investigate the distribution of NH₃-N and NO₃-N. The test data was utilized to calibrate and validate the HYDRUS-2D. The validated model was subsequently used to analyze the distribution of NH₃-N and NO₃-N within the different GIs under three different rainfall conditions: inflow/runoff pollutant concentration, rainfall recurrence interval (runoff amount of a rainfall event), and number of dry days (during which no rainwater infiltrates into the soil). The average NH₃-N and NO₃-N concentrations in the upper soil (0-30 cm) of the GIs were about 4.8 and 2.4 times those of the lower layer (30-60 cm). Compared to the control (V_c), the average NH₃-N concentrations in soil with Sophora japonica (V_s) and Malus baccata (V_m) decreased by 15.8% and 35.1% while those of NO₃-N decreased by 15.5% and 27.2%, respectively. Degrees of influence by the three factors on the average soil NH₃-N and NO₃-N concentrations were inflow concentration > number of dry days > recurrence interval. The number of dry days was the smallest influence factor for the overflow N load while the inflow concentration was the most significant influence factor for the outflow, bio-utilization, and soil nitrogen loads. Compared to the control, outflow (groundwater recharge) loads of NO₃-N from the V_s and V_m increased by 14.0-16.6% and 3.7-6.8%, respectively under different conditions. The overflow (runoff) loads from V_s and V_m decreased by 16.8-36.3% and 6.6%-8.4%, respectively. A multiple regression equation was used to establish a quantitative coupling relationship between N pollutant load reduction rates and influence factors (R² ≥ 0.83). This relationship can be used to estimate the runoff treatment effectiveness of green infrastructure on target pollutants.

Keywords: Dry days; Green infrastructure; Nitrogen; Rainfall; Recurrence interval; Woody plant.

MeSH terms

Ammonia*
Nitrates* / analysis
Nitrogen / analysis
Rain
Soil

Substances

Nitrates
Soil
Ammonia
Nitrogen