Differences of Nutrient and Heavy Metals Migration in Soil-plant System Irrigated by Reclaimed Water and Livestock Wastewater

LIU Yuan; CUI Erping; LI Zhongyang; DU Zhenjie; GAO Feng; FAN Xiangyang

doi:10.13522/j.cnki.ggps.2017.0408

Abstract：The effect of reclaimed water and livestock wastewater as agricultural alternative water source on nutri-ent and heavy metals migration in soil-plant system has been explored deeply, but the comparative studies in the same experiment conditions are relatively rare.[Objective]Explore the migration characteristics of heavy met-als in soil-plant system under reclaimed water and livestock wastewater irrigation.[Method]Rhizobox culture method was employed to investigate the differences of nutrient and heavy metals migration in soil-plant system ir-rigated by reclaimed water and livestock wastewater.[Result]The plant growth condition was better under the livestock wastewater irrigation than that under reclaimed water. Irrigation of these two kinds of water could both increase the nutrient content in soil and plants, and the livestock wastewater behaved better. Compared with CK, total N, total P, total K, total Mg, available Fe, available Mn, available N, available P, available K and organic matter content of soil under the livestock wastewater irrigation increased by 4.78％, 8.76％, 4.33％, 7.62％, 19.04％, 8.99％, 3.55％, 29.40％, 14.14％and 21.63％respectively, and N, P, K, Ca and Mg content of plant roots increased by 49.83％, 23.90％, 15.44％, 4.09％and 8.65％, respectively. What's more, more heavy metals were transported to the soil and plants irrigated by livestock wastewater, especially Cu and Zn. The Zn content of plant roots and stems of livestock wastewater treatment increased by 102.35％ and 244.49％ significantly compared with CK. However, compared with livestock wastewater, the reclaimed water irrigation raised the soil electric conductivity.[Conclusion]Livestock wastewater irrigation has better improvement of soil and plant nutrient than reclaimed water. However, reclaimed water irrigation cam increase the risk of secondary soil salinization, and livestock wastewater irrigation cam increase the risk of heavy metals accumulation in soil and plants.