Published September 9, 2014
Journal of Environmental Quality
TECHNICAL REPORTS Organic Compounds in the Environment
Emission Reduction of 1,3-Dichloropropene by Soil Amendment with Biochar Qiuxia Wang, Liangang Mao, Dong Wang, Dongdong Yan, Taotao Ma, Pengfei Liu, Chenglei Zhang, Ruoqi Wang, Meixia Guo, and Aocheng Cao*
T
he fumigant 1,3-dichloropropene (1,3-D) is an effective alternative to methyl bromide (MeBr) for controlling nematodes and some soil-borne fungal pathogens (Csinos et al., 2000; Desaeger et al., 2008; D. Wang et al., 2009). Methyl bromide is an effective broad-spectrum soil fumigant for controlling nematodes, fungal pathogens, and weeds (MBTOC, 2011). However, the production and use of MeBr is being phased out in all developed and developing countries except for uses under critical use exemption and quarantine and preshipment because it contributes to the depletion of the stratospheric ozone (WMO, 2010). 1,3-Dichloropropene can be used alone or in combination with other soil fumigants/treatments to further enhance pest control efficacy. However, 1,3-D (mixture of cis- and trans-isomers) has relatively high vapor pressure (0.44–0.66 psi) under ambient temperature and a low boiling point (104–114°C) (Gan et al., 2000), so it could result in high emissions if applied without proper surface sealing (Thomas et al., 2004; Q. Wang et al., 2009; Wang et al., 2001). Furthermore, 1,3-D has a high acute toxicity, and exposure to high concentrations of 1,3-D can cause respiratory problems, skin and eye irritation, and kidney damage for field workers and bystanders (Cox, 1992). Therefore, 1,3-D emission must be reduced or eliminated. Many field and laboratory studies have evaluated various strategies for reducing fumigant emissions from soil application. Ashworth et al. (2011) summarized these strategies into three categories: (i) enhancing fumigant degradation in the soil by the application of either a chemical amendment such as ammonium thiosulfate or an organic material, (ii) restricting the fumigant’s upward diffusion through the soil by reducing air-filled porosity via soil surface compaction or the addition of irrigation water, and (iii) restricting the fumigant’s diffusion across the soil–air interface by the use of plastic coverings such as a high-density polyethylene film or a low-permeability virtually impermeable film.
Abstract Soil fumigation is an important treatment in the production chain of fruit and vegetable crops, but fumigant emissions contribute to air pollution. Biochar as a soil amendment has shown the potential to reduce organic pollutants, including pesticides, in soils through adsorption and other physicochemical reactions. A laboratory column study was performed to determine the effects of soil applications of biochar for reducing emissions of the fumigant 1,3-dichloropropene (1,3-D). The experimental treatments comprised of unamended and amended with biochar at doses of 0, 0.5, 1, 2, and 5% (w/w) in the top 5 cm soil layer. The unamended treatment resulted in the highest emission peak flux at 48 to 66 mg m-2 s-1. Among the biochar amendment treatments, the highest peak flux (0.83 mg m-2 s-1) was found in the biochar 0.5% treatment. The total emission loss was 35.7 to 40.2% of applied for the unamended treatment and 99.8% and showed total 1,3-D emission loss by >92% compared with that without biochar. The amendment of surface soil with biochar shows a great potential for reducing fumigant emissions.
Copyright © American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. 5585 Guilford Rd., Madison, WI 53711 USA. All rights reserved. No part of this periodical may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher.
Q. Wang, L. Mao, D. Yan, T. Ma, P. Liu, R. Wang, M. Guo, and A. Cao, Key Laboratory of Pesticide Chemistry and Application, Ministry of Agriculture, Dep. of Pesticide, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; D. Wang, USDA–ARS, Water Management Research Unit, San Joaquin Valley Agricultural Sciences Center, Parlier, CA 93648; C. Zhang, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China. Assigned to Associate Editor Patryk Oleszczuk.
J. Environ. Qual. 43:1656–1662 (2014) doi:10.2134/jeq2014.02.0075 Received 19 Feb. 2014. *Corresponding author (
[email protected]).
Abbreviations: 1,3-D, 1,3-dichloropropene; LOD, limit of detection; LOQ, limit of quantification; MeBr, methyl bromide; PE, polyethylene; SSA, specific surface area.
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Recommended as a soil amendment (Hunt et al., 2010; Lehmann and Stephen, 2009), biochar is a highly porous charcoal substance produced by heating organic materials (e.g., wood chips, corn stover, or poultry litter) under conditions of relatively low temperature and with limited or no oxygen (Lehmann, 2007). Biochar porosity increases significantly with increasing production temperature, leading to increases in specific surface area (SSA) (e.g., from
