Nutrients and Nonessential Elements in Soil after 11 Years of Wastewater Irrigation
- B. F. Faria Pereiraa,
- Zhenli He *ab,
- Peter J. Stoffellaa,
- Celia R. Montesc,
- Adolpho J. Melfid and
- Virupax C. Baligare
- a Indian River Research and Education Center, Institute of Food and Agricultural Sciences, Univ. of Florida, 2199 S. Rock Rd., Fort Pierce, FL 34945
b Faculdade de Ciências Agrárias, Univ. Federal do Amazonas, 69077-000, Minicampus, Coroado, Setor Sul, Manaus, AM, Brazil
c Center for Nuclear Energy in Agriculture, Univ. of Sao Paulo, Avenida Centenário, 303, 13416-903, Piracicaba, São Paulo, Brazil
d Univ. of Sao Paulo, P.O. Box 09, Piracicaba, São Paulo, Brazil, 13418-900
e USDA–ARS, Beltsville Agricultural Research Center, Beltsville, MD 20705-2350. Assigned to Associate Editor Joselito M. Arocena
Irrigation of citrus (Citrus aurantium L. × Citrus paradise Macf.) with urban reclaimed wastewater (RWW) can be economical and conserve fresh water. However, concerns remain regarding its deleterious effects on soil quality. We investigated the ionic speciation (ISP) of RWW and potential impacts of 11 yr of irrigation with RWW on soil quality, compared with well-water (WW) irrigation. Most of nutrients (∼53–99%) in RWW are free ionic species and readily available for plant uptake, such as: NH4+, NO3−, K+, Ca2+, Mg2+, SO42−, H3BO3, Cl−, Fe2+, Mn2+, Zn2+, Co2+, and Ni2+, whereas more than about 80% of Cu, Cr, Pb, and Al are complexed with CO3−, OH−, and/or organic matter. The RWW irrigation increased the availability and total concentrations of nutrients and nonessential elements, and soil salinity and sodicity by two to three times compared with WW-irrigated soils. Although RWW irrigation changed many soil parameters, no difference in citrus yield was observed. The risk of negative impacts from RWW irrigation on soil quality appears to be minimal because of: (i) adequate quality of RWW, according to USEPA limits; (ii) low concentrations of metals in soil after 11 yr of irrigation with RWW; and (iii) rapid leaching of salts in RWW-irrigated soil during the rainy season.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © 2012. . Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.