Assessment of long-term wastewater irrigation impacts on the soil geochemical properties and the bioaccumulation of heavy metals to the agricultural products
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An extensive field survey was employed for assessing the impacts of long-term wastewater irrigation of forage crops and orange orchards in three suburban agricultural areas in Cyprus (areas I, II, and III), as compared to rainfed agriculture, on the soil geochemical properties and the bioaccumulation of heavy metals (Zn, Ni, Mn, Cu, Co) to the agricultural products. Both ryegrass fields and orange orchards in areas I and II were continuously wastewater irrigated for 10 years, whereas clover fields in area III for 0.5, 4, and 8 years. The results revealed that wastewater reuse for irrigation caused a slight increase in soil salinity and Cl− content in areas I and II, and a remarkable increase, having strong correlation with the period in which wastewater irrigation was practiced, in area III. Soil salinization in area III was due to the high electrical conductivity (EC) of the wastewater applied for irrigation, attributed to the influx of seawater to the sewage collection network in area III. In addition, the wastewater irrigation practice resulted in a slight decrease of the soil pH values in area III, while a subtle impact was identified regarding the CaCO3, Fe, and heavy metal content in the three areas surveyed. The heavy metal content quantified in the forage plants’ above-ground parts was below the critical levels of phytotoxicity and the maximum acceptable concentration in dairy feed, whereas heavy metals quantified in orange fruit pulp were below the maximum permissible levels (MPLs). Heavy metal phytoavailability was confined due to soil properties (high pH and clay content), as evidenced by the calculated low transfer factor (TF).
KeywordsElectrical conductivity Forage crops Heavy metal Orange Public health Wastewater irrigation
The authors wish to thank all the personnel of the Cyprus Agricultural Research Institute involved in the study for their excellent technical assistance. This study was undertaken in collaboration with Nireas-International Water Research Center of the University of Cyprus and supported by Cyprus Agricultural Research Institute Internal Grant to Anastasis Christou.
- APHA. (1998). Standard method for the examination of water and wastewater (20th ed.). Washington, DC: APHA, AWWA and WEF.Google Scholar
- Aycicek, M., Kaplan, O., & Yaman, M. (2011). Effect of cadmium on germination, seedling growth and metal contents of sunflower (Helianthus annuus L.). Asian Journal of Chemistry, 20(4), 2663–2672.Google Scholar
- Ayers, R. S., & Westcot, D. W. (Eds.). (1985). Ware quality for irrigation (FAO irrigation and drainage paper 29). Rome: FAO.Google Scholar
- Belaid, N., Neel, C., Lenain, J. F., Buzier, R., Kallel, M., Ayoub, T., et al. (2012). Assessment of metal accumulation in calcareous soil and forage crops subjected to long-term irrigation using treated wastewater: case of El Hajeb-Sfax, Tunisia. Agriculture, Ecosystems & Environment, 158, 83–93.CrossRefGoogle Scholar
- Datta, S. P., Subba Rao, A., & Ganeshamurthy, A. N. (1997). Effect of electrolytes coupled with variable stirring on soil pH. Journal of Indian Society of Soil Science, 45, 185–187.Google Scholar
- Day, P. R. (1965). Fractionation and particle size analysis. In C. A. Black (Ed.), Methods of soil analysis. Part I. Agronomy 9 (pp. 545–567). Madison: American Society of Agronomy, Inc.Google Scholar
- EEC (1986). Council Directive of 12 June 1986 on the protection of the environment, and in particular of the soil, when sewage sludge is used in agriculture (86/278/EEC). http://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:31986L0278&from=EN. Accessed 25 Jun 2013.
- European Commission. (2003). Opinion of the scientific committee on animal nutrition on undesirable substances in feed. Brussels: European Commission, Health and Consumer Protection Directorate. European Commission.Google Scholar
- Hering, D., Borja, A., Carstensen, J., Carvalho, L., Elliott, M., Feld, C. K., et al. (2010). The European Water Framework Directive at the age of 10: a critical review of the achievements with recommendations for the future. Science of the Total Environment, 408(19), 4007–4019.CrossRefGoogle Scholar
- Maas, E. V., & Hoffman, G. J. (1977). Crop salt tolerance—current assessment. Journal of the Irrigation and Drainage Division. ASCE, 103, 115–134.Google Scholar
- Metochis, C. (1997). Assessment of irrigation water needs of main crops of Cyprus. Cyprus Agricultural Research Institute Series. Cyprus: Ministry of Agriculture, Natural Resources and Environment.Google Scholar
- Muchuweti, M., Birkett, J. W., Chinyanga, E., Zvauya, R., Scrimshaw, M. D., & Lester, J. N. (2006). Heavy metal content of vegetables irrigated with mixtures of wastewater and sewage sludge in Zimbabwe: implications for human health. Agriculture, Ecosystems & Environment, 112(1), 41–48.CrossRefGoogle Scholar
- Pescod, M. B. (Ed.). (1992). Wastewater treatment and use in agriculture-FAO irrigation and drainage paper 47. Rome: FAO.Google Scholar
- U.S. Environmental Protection Agency. (1998). Microwave assisted acid digestion of sediments, sludges, soils, and oils. Washington, DC: Office of Solid Waste and Emergency Response, U.S. Government Printing Office.Google Scholar
- UN (2013). Water scarcity. http://www.un.org/waterforlifedecade/scarcity.shtml. Accessed 25 Jun 2013.
- WHO/FAO (2007). Joint FAO/WHO food standard programme codex alimentarius commission, 13th Session. Report of the thirty eight session of the codex committee on food hygiene. Houston, United States of America, ALINORM 07/30/13.Google Scholar
- Zheng, S. A., Zheng, X., Zhang, T., Liu, S., & Li, X. (2012). Distribution and fractionation of heavy metals in soil profiles irrigated with wastewater for different periods of time. Fresenius Environmental Bulletin, 21(10), 2881–2890.Google Scholar