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Buates J, Sun Y, He M, Mohanty SK, Khan E, Tsang DCW. Performance of wood waste biochar and food waste compost in a pilot-scale sustainable drainage system for stormwater treatment. Environ Pollut 2024; 348:123767. [PMID: 38492753 DOI: 10.1016/j.envpol.2024.123767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 12/28/2023] [Accepted: 03/09/2024] [Indexed: 03/18/2024]
Abstract
Sustainable drainage system (SuDS) for stormwater reclamation has the potential to alleviate the water scarcity and environmental pollution issues. Laboratory studies have demonstrated that the capacity of SuDS to treat stormwater can be improved by integrating biochar and compost in the filter media, whereas their performance in scaled-up applications is less reported. This study examines the effectiveness of a pilot-scale SuDS, bioswale followed by bioretention, amended with wood waste biochar (1, 2, and 4 wt.%) and food waste compost (2 and 4 wt.%) to simultaneously remove multiple pollutants including nutrients, heavy metals, and trace organics from the simulated stormwater. Our results confirmed that SuDS modified with both biochar (2 wt.%) and compost (2 wt.%) displayed superior water quality improvement. The system exhibited high removal efficiency (> 70%) for total phosphorus and major metal species including Ni, Pb, Cd, Cr, Cu, and Zn. Total suspended solids concentration was approaching the detection limit in the effluent, thereby confirming its capability to reduce turbidity and particle-associated pollutants from stormwater. Co-application of biochar and compost also moderately immobilized trace organic contaminants such as 2,4-dichlorophenoxyacetic acid, diuron, and atrazine at field-relevant concentrations. Moreover, the soil amendments amplified the activities of enzymes including β-D-cellobiosidase and urease, suggesting that the improved soil conditions and health of microbial communities could possibly increase phyto and bioremediation of contaminants accumulated in the filter media. Overall, our pilot-scale demonstration confirmed that the co-application of biochar and compost in SuDS can provide a variety of benefits for soil/plant health and water quality.
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Affiliation(s)
- Jittrera Buates
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Yuqing Sun
- School of Agriculture, Sun Yat-sen University, Guangdong, China
| | - Mingjing He
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Sanjay K Mohanty
- Department of Civil and Environmental Engineering, University of California Los Angeles, United States
| | - Eakalak Khan
- Department of Civil and Environmental Engineering and Construction, University of Nevada, Las Vegas, 89154, United States
| | - Daniel C W Tsang
- Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
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2
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Zhou J, Zhang Z, Xiong J, Shi W, Liang L, Zhang F, Zhang F. Nitrogen removal performance of bioretention cells under polyethylene (PE) microplastic stress. Environ Pollut 2023; 338:122655. [PMID: 37778494 DOI: 10.1016/j.envpol.2023.122655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 09/10/2023] [Accepted: 09/28/2023] [Indexed: 10/03/2023]
Abstract
The use of bioretention cells as a stormwater control measure allows stormwater runoff to be collected and filtered, effectively removing microplastics and other pollutants from stormwater. This study investigated the effect of polyethylene microplastics (PE-MPs) retention on the bioretention cell, in terms of denitrification performance and microbial community structure. Four PE-MP exposures were compared at different concentrations of 0, 250, 500 and 1000 mg/L under alternating dry and wet period conditions. Results showed that the removal efficiency reduced by 14.99%, 28.37% and 18.59% with PE-MP concentrations of 250, 500 and 1000 mg/L. The NO3--N removal efficiency increased by 36.19%, 20.19% and 35.39%. After 8 days of dry conditions, the NO3--N removal efficiencies of the bioretention cells were reduced by 36.66%, 46.86% and 31.11% compared to those after 2 days of dry conditions. Microbial sequencing results indicated that the accumulation of PE-MPs changed the microbial community structure within the bioretention cell filler material, promoting the growth of bacteria such as Actinobacteria, Bacteroidetes and Firmicutes. Furthermore, PE-MPs reduced the relative abundance of nitrifying bacteria (e.g. Nitrospira) within the bioretention cell and promoted denitrifying bacteria (e.g. Dechloromonas and Hydrogenophaga), along with numerous other genera such as Azotobacter and Nocardia.
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Affiliation(s)
- Jiajia Zhou
- Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Yan Ta Road. No.13, Xi'an, 710055, China
| | - Zinuo Zhang
- Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Yan Ta Road. No.13, Xi'an, 710055, China
| | - Jiaqing Xiong
- Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Yan Ta Road. No.13, Xi'an, 710055, China.
| | - WeiPeng Shi
- Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Yan Ta Road. No.13, Xi'an, 710055, China
| | - Lipeng Liang
- Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, PR China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Yan Ta Road. No.13, Xi'an, 710055, China
| | - Fanghong Zhang
- Qinghai Provincial Civil Air Defense Engineering Design and Research Institute Co., Ltd, China
| | - Fei Zhang
- Wuhan Municipal Engineering Design & Research Institute Co., Ltd, China
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Zhang Z, Li J, Li Y, Wang D, Zhang J, Zhao L. Assessment on the cumulative effect of pollutants and the evolution of micro-ecosystems in bioretention systems with different media. Ecotoxicol Environ Saf 2021; 228:112957. [PMID: 34775342 DOI: 10.1016/j.ecoenv.2021.112957] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 10/27/2021] [Accepted: 10/30/2021] [Indexed: 06/13/2023]
Abstract
Bioretention system is one of the most used green stormwater infrastructures (GSI), and its media is a key factor in reducing runoff water volume and purifying water quality. Many studies have investigated media improvement to enhance the pollutant removal capacity. However, the long-term cumulative effect and microbial effect of pollutants in the modified-media bioretention system is less known. This study investigated the cumulative effect of pollutants and their influence on microbial characteristics in conventional and modified media bioretention system. The addition of modifiers increased the background content of pollutants in the media, and the accumulation of pollutants in planting soil (PS) and bioretention soil mixing + water treatment residuals (BSM+WTR) was relatively higher after the simulated rainfall experiment. The accumulation of pollutants led to a decrease in dehydrogenase activity, and an increase in urease and invertase activities. Ten dominant bacterial species at the phylum level were found in all bioretention systems. The relative abundances of the bacteria with good viability under low nutritional conditions decreased, while the species which could live in the pollutant-rich environment increased. The accumulation of pollutants in the bioretention system led to the extinction of some functional microorganisms. The better the effects of modified media on pollutant removal showed, the more obvious effect on the media micro-ecosystem was. To ensure the long-term efficient and stable operation of the modified-media bioretention system, we recommend balancing the pollutant removal efficiency and cumulative effect in modified-media bioretention systems.
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Affiliation(s)
- Zhaoxin Zhang
- State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China, Xi'an University of Technology, Xi'an 710048, China; Shaanxi Provincial Land Engineering Construction Group Co., Ltd., Xi'an 710075, China
| | - Jiake Li
- State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China, Xi'an University of Technology, Xi'an 710048, China.
| | - Yajiao Li
- School of Architecture and Civil Engineering, Xi'an University of Science and Technology, Xi'an 710054, China
| | - Dongqi Wang
- State Key Laboratory of Eco-hydraulics in Northwest Arid Region of China, Xi'an University of Technology, Xi'an 710048, China
| | - Jingyu Zhang
- School of Architecture and Civil Engineering, Xi'an University of Science and Technology, Xi'an 710054, China
| | - Lingzhi Zhao
- School of Architecture and Civil Engineering, Xi'an University of Science and Technology, Xi'an 710054, China
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Skorobogatov A, He J, Chu A, Valeo C, van Duin B. The impact of media, plants and their interactions on bioretention performance: A review. Sci Total Environ 2020; 715:136918. [PMID: 32007889 DOI: 10.1016/j.scitotenv.2020.136918] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 01/14/2020] [Accepted: 01/23/2020] [Indexed: 06/10/2023]
Abstract
Bioretention systems have gained considerable popularity as a more natural approach to stormwater management in urban environments. The choice of bioretention media is frequently cited as one of the critical design parameters with the ultimate impact on the performance of the system. The goal of this review is to highlight data that challenge the importance of media as being the dominant design parameter and argue that the long-term performance is shaped by the interactions between media and the living components of a bioretention system, especially vegetation. Some of the key interactions are related to the impact of plant roots on media pore structure, which has implications on infiltration, storage capacity, and treatment. Another relevant interaction pertains to evapotranspiration and the associated impacts on the water balance and the water quality performance of bioretention systems. The impacts of vegetation on the media are highlighted and actual, as well as potential, impacts of plant-media interactions on bioretention performance are presented.
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Affiliation(s)
- Anton Skorobogatov
- Civil Engineering, Schulich School of Engineering, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada
| | - Jianxun He
- Civil Engineering, Schulich School of Engineering, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada.
| | - Angus Chu
- Civil Engineering, Schulich School of Engineering, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada
| | - Caterina Valeo
- Mechanical Engineering, University of Victoria, 3800 Finnerty Road, Victoria, BC V8P 5C2, Canada
| | - Bert van Duin
- The City of Calgary, 625 - 25 Ave S.E., Calgary, AB T2G 4K8, Canada
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Xu D, Lee LY, Lim FY, Lyu Z, Zhu H, Ong SL, Hu J. Water treatment residual: A critical review of its applications on pollutant removal from stormwater runoff and future perspectives. J Environ Manage 2020; 259:109649. [PMID: 32072941 DOI: 10.1016/j.jenvman.2019.109649] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Revised: 09/26/2019] [Accepted: 09/28/2019] [Indexed: 06/10/2023]
Abstract
In recent years, many studies have been conducted on using different filter media in bioretention systems for stormwater runoff treatment. This critical review paper provides a comprehensive review on the current state of water treatment residual (WTR), a recycled material that can be used as bioretention filter media for removals of key stormwater runoff pollutants (especially phosphorus) and future perspectives with innovative modification on WTR applied for pathogen removal from stormwater runoff. This review paper comprised (i) a brief summary of the reported WTR characteristics, (ii) a thorough evaluation of WTR performance on major pollutants removal from stormwater runoff (iii) a discussion on phosphorus removal mechanisms by WTR applied in the stormwater runoff treatment, and (iv) a review of the future perspectives of WTR for pathogen removal and other potential practical application in the field of stormwater treatment. As outlined in this review, WTR in stormwater runoff treatment has yet to be fully explored. The possible enhancements, especially metal surface modification on WTR are reviewed to bring about the widespread use of WTR in stormwater reuse practices.
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Affiliation(s)
- Dong Xu
- Department of Civil and Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, 117576, Singapore
| | - Lai Yoke Lee
- Centre for Water Research, Department of Civil and Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, 117576, Singapore
| | - Fang Yee Lim
- Centre for Water Research, Department of Civil and Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, 117576, Singapore
| | - Zhiyang Lyu
- Department of Materials Science and Engineering, National University of Singapore, 117574, Singapore
| | - Hao Zhu
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Say Leong Ong
- Department of Civil and Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, 117576, Singapore
| | - Jiangyong Hu
- Department of Civil and Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, 117576, Singapore.
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Sun Y, Chen SS, Lau AYT, Tsang DCW, Mohanty SK, Bhatnagar A, Rinklebe J, Lin KYA, Ok YS. Waste-derived compost and biochar amendments for stormwater treatment in bioretention column: Co-transport of metals and colloids. J Hazard Mater 2020; 383:121243. [PMID: 31563764 DOI: 10.1016/j.jhazmat.2019.121243] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 08/29/2019] [Accepted: 09/15/2019] [Indexed: 06/10/2023]
Abstract
Bioretention systems, as one of the most practical management operations for low impact development of water recovery, utilize different soil amendments to remove contaminants from stormwater. For the sake of urban sustainability, the utilization of amendments derived from waste materials has a potential to reduce waste disposal at landfill while improving the quality of stormwater discharge. This study investigated the efficiency of food waste compost and wood waste biochar for metal removal from synthetic stormwater runoff under intermittent flow and co-presence of colloids. Throughout intermittent infiltration of 84 pore volumes of stormwater, columns amended with compost and biochar removed more than 50-70% of influent metals, whereas iron-oxide coated sand was much less effective. Only a small portion of metals adsorbed on the compost (< 0.74%) was reactivated during the drainage of urban pipelines that do not flow frequently, owing to abundant oxygen-containing functional groups in compost. In comparison, co-existing kaolinite enhanced metal removal by biochar owing to the abundance of active sites, whereas co-existing humic acid facilitated mobilization via metal-humate complexation. The results suggest that both waste-derived compost and biochar show promising potential for stormwater harvesting, while biochar is expected to be more recalcitrant and desirable in field-scale bioretention systems.
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Affiliation(s)
- Yuqing Sun
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Season S Chen
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Abbe Y T Lau
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Daniel C W Tsang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China.
| | - Sanjay K Mohanty
- Department of Civil and Environmental Engineering, University of California, Los Angeles, CA, 90095-1593, USA
| | - Amit Bhatnagar
- Department of Environmental and Biological Sciences, University of Eastern Finland, P.O. Box 1627, FI-70211, Kuopio, Finland
| | - Jörg Rinklebe
- University of Wuppertal, School of Architecture and Civil Engineering, Institute of Foundation Engineering, Water and Waste Management, Laboratory of Soil and Groundwater-Management, Pauluskirchstraße 7, 42285, Wuppertal, Germany; Department of Environment, Energy and Geoinformatics, Sejong University, 98 Gunja-Dong, Seoul, Republic of Korea
| | - Kun-Yi Andrew Lin
- Department of Environmental Engineering, National Chung Hsing University, 250 Kuo-Kuang Road, Taichung, Taiwan
| | - Yong Sik Ok
- Korea Biochar Research Center, O-Jeong Eco-Resilience Institute (OJERI) & Division of Environmental Science and Ecological Engineering, Korea University, Seoul, 02841, Republic of Korea
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Lau AYT, Tsang DCW, Graham NJD, Ok YS, Yang X, Li XD. Surface-modified biochar in a bioretention system for Escherichia coli removal from stormwater. Chemosphere 2017; 169:89-98. [PMID: 27863306 DOI: 10.1016/j.chemosphere.2016.11.048] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 11/09/2016] [Accepted: 11/10/2016] [Indexed: 05/22/2023]
Abstract
Bioretention systems have been recommended as one of the best management practices for low impact development for water recycling/reuse systems. Although improvement of the stormwater quality has been reported regarding pollutants eliminations such as suspended solids and heavy metals, a substantial removal of indicator bacteria is required for possible non-potable reuse. This study investigated the efficiency of wood biochar with H2SO4-, H3PO4-, KOH-, and amino-modifications for E. coli removal from synthetic stormwater under intermittent flow. The H2SO4-modified biochar showed a specific surface area of 234.7 m2 g-1 (approximately double the area of original biochar), whereas a substantial reduction in surface area was found with amino-modified biochar. The E. coli removal (initial concentration of 0.3-3.2 × 106 CFU mL-1) by modified biochars as filter media was very promising with, for example, over 98% removal efficiency in the first 20 pore volumes of stormwater infiltration and over 92% removal by the end of the second infiltration cycle. Only a small portion of E. coli attached on the modified biochars (<0.3%, except KOH- and amino-modified biochars) was remobilized during the drainage phase of intermittent flow. The high removal capacity and stability against drainage were attributed to the high surface area, porous structure, and surface characteristics (e.g. hydrophobicity and O-containing functional groups) of the biochars. Thus, the H2SO4-modified biochar appeared to give the best treatment performance.
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Affiliation(s)
- Abbe Y T Lau
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Daniel C W Tsang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China.
| | - Nigel J D Graham
- Department of Civil and Environmental Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, UK
| | - Yong Sik Ok
- Korea Biochar Research Center & School of Natural Resources and Environmental Science, Kangwon National University, Chuncheon 24341, South Korea
| | - Xin Yang
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China
| | - Xiang-Dong Li
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
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Chahal MK, Shi Z, Flury M. Nutrient leaching and copper speciation in compost-amended bioretention systems. Sci Total Environ 2016; 556:302-9. [PMID: 26977536 DOI: 10.1016/j.scitotenv.2016.02.125] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 02/18/2016] [Accepted: 02/18/2016] [Indexed: 05/14/2023]
Abstract
Bioretention systems are designed to remove contaminants from stormwater; however, studies have shown that bioretention systems can export excess nitrogen, phosphorus, and copper when amended with compost. The objectives of this study were (1) to quantify removal of nitrates, phosphorus, copper, and dissolved organic matter (DOM) from compost-amended bioretention systems, and (2) to investigate the role of DOM on the leaching of copper. Simulated bioretention systems were irrigated with stormwater for seven storms in two-weeks intervals. Leachates were analyzed for nutrients, copper, and DOM. Visual MINTEQ was used to determine the speciation of copper and to quantify interactions of copper with DOM. Results showed that compost-amended bioretention systems were a source of nitrates, phosphorus, and DOM. Nitrate and phosphorus amounts were elevated up to three orders of magnitude in the leachate compared to the stormwater itself. Bioretention systems were a source for copper during the first 3-5 storms, but during later storms, they were a sink for copper. Copper speciation modeling indicated that the majority of dissolved copper was complexed with DOM. Dissolved organic matter thus helps to mobilize copper from the compost, particularly in the first few storms after compost application. However, since copper-DOM complexes are usually much less toxic than free copper ions, we expect that compost amendments may reduce harmful effects of copper on aquatic organisms.
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Affiliation(s)
- Maninder K Chahal
- Department of Crop & Soil Sciences, Washington State University, Pullman, WA 99164, USA; Department of Crop & Soil Sciences, Washington State University, Puyallup, WA 98374, USA
| | - Zhenqing Shi
- School of Environment and Energy, South China University of Technology, Guangzhou, Guangdong 51006, PR China
| | - Markus Flury
- Department of Crop & Soil Sciences, Washington State University, Pullman, WA 99164, USA; Department of Crop & Soil Sciences, Washington State University, Puyallup, WA 98374, USA.
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Mullane JM, Flury M, Iqbal H, Freeze PM, Hinman C, Cogger CG, Shi Z. Intermittent rainstorms cause pulses of nitrogen, phosphorus, and copper in leachate from compost in bioretention systems. Sci Total Environ 2015; 537:294-303. [PMID: 26282763 DOI: 10.1016/j.scitotenv.2015.07.157] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 07/30/2015] [Accepted: 07/31/2015] [Indexed: 05/15/2023]
Abstract
Bioretention systems rely on vegetation and mixtures of soil, sand, and compost to filter stormwater runoff. However, bioretention systems can also leach metals and nutrients, and compost may be a major contributor to this leaching. To safely implement bioretention systems, it is crucial to determine the composition of compost leachate. We characterized and quantified the leachate composition of compost following intermittent, simulated storm events. Columns of municipal compost were irrigated to simulate 6-month, 24-hour rain storms in the Seattle-Tacoma region. Outflow was analyzed for pH, electrical conductivity (EC), particulate concentration, surface tension, dissolved organic carbon (DOC), nitrogen, phosphorus, and copper. Results indicate a decrease of chemical concentrations over the course of individual storms and following repeated storms, but each new storm released another peak of constituents. The decrease in phosphorus, copper, and DOC concentrations with repeated storms was slower than for nitrate and EC. Nuclear magnetic resonance (NMR) and Fourier transform infrared spectroscopy (FTIR) showed that the DOC consisted mainly of aliphatic and aromatic components typical of fulvic and humic acids. Less than 3% of the original copper content from the compost leached out even after nine storm events. Nonetheless, copper concentrations in the leachate exceeded regulatory discharge standards. Our results show that compost can serve as a sustained source of leaching of nutrients and metals.
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Affiliation(s)
- Jessica M Mullane
- Department of Crop and Soil Sciences, Washington State University, Puyallup, WA 98371, Pullman, WA 99164, USA
| | - Markus Flury
- Department of Crop and Soil Sciences, Washington State University, Puyallup, WA 98371, Pullman, WA 99164, USA.
| | - Hamid Iqbal
- Department of Crop and Soil Sciences, Washington State University, Puyallup, WA 98371, Pullman, WA 99164, USA; Institute of Environmental Sciences and Engineering, School of Civil and Environmental Engineering, National University of Sciences and Technology, Sector H-12, Islamabad, Pakistan
| | - Patrick M Freeze
- Department of Crop and Soil Sciences, Washington State University, Puyallup, WA 98371, Pullman, WA 99164, USA
| | - Curtis Hinman
- Natural Resources Program Extension, Washington State University, Puyallup, WA 98371, USA
| | - Craig G Cogger
- Department of Crop and Soil Sciences, Washington State University, Puyallup, WA 98371, Pullman, WA 99164, USA
| | - Zhenqing Shi
- Department of Crop and Soil Sciences, Washington State University, Puyallup, WA 98371, Pullman, WA 99164, USA
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