Tundzha River Water Quality as a Source for Irrigation in Agriculture

M. Todorova, Z. Yaneva, G. Kostadinova, Ch. Miteva, G. Petkov, N. Georgieva

Abstract: The aim of the study was to investigate the quality of Tundzha River water in the upper stream during the summer of 2010 by 25 physicochemical indices, and assessed their suitability for irrigation in agriculture. For sampling and sample preparation of water, international ISO and BSS references were used. Sample analyses were made by equipment Mrlti 340i/SET, spectrophotometric methods and AAS. It was established that the quality of the surface water corresponded to the standards for irrigation according to 23 indices: temperature, pH, conductivity, total hardness, Ca, Mg, dissolved oxygen, BOD5, COD, ammonium (NH4 +), nitrites (NO2 -), nitrates (NO3 -), chlorides (Cl-), sulfates (SO4 2-), phosphates (PO4 3-), K, Fe, Ni, Cu, Zn, Pb, Cd and Cr(VI). Deviations from the regulated standards were established for suspended solids and Mn. The correlation matrix revealed appreciable mutual relationship: between suspended solids-dissolved oxygen, conductivity-BOD, total hardness-BOD and total hardness-conductivity (R2 0.957 - 0.999), and between Mg-Ca; K-Ca; Mn-Ca; Mn-Mg; Mn-K; Ni-K; Ni-Zn; Cd-Ca; Cd-Mg; Cd-K; Cd-Mn and Cd-Ni (R2 0.951 - 0.999) in the studied water samples. Data analysis revealed that the anthropogenic impact on Tundzha River water in the investigated area does not affect water quality with a view to its applicability for irrigation purposes. The registered deviations from the quality standard for Mn could be explained by the discharge of industrial and sewage wastewaters from Kazanlak City (46545 inhabitants, large industrial center).

Keywords: assessment; indices; irrigation; water quality

Date published: 2019-02-20