Assessment of the contamination level by trace metal (cadmium, copper, nickel and zinc) of sediments in the Boumerzoug wadi and its tributaries, and their transfer to the Chenοpοdiaceae Spinacia oleracea (L.)
The aim of this study is to assess the distribution of four trace metals (TM): cadmium, copper, nickel and zinc in roots and leaves of a Chenopodiaceae Spinacia oleracea (L.) in relation to the contamination level of the sediments of the Boumerzoug wadi and its tributaries. Located in the Constantinois in Northeast Algeria, the wadi drains a watershed of 1 832 km2 with its urban and industrial areas. A total of 14 stations, 5 in Boumerzoug wadi and 9 in its tributaries, were selected in strategic points and sampled at five occasions in May, September, and December 2016, as well as in March and July 2017. The mean TM levels in the sediments are 0.44 ± 0.30 mg∙kg-1 (dry weight) for Cd, 43.61 ± 36.45 mg∙kg-1 (dw) for Cu, 35.16 ± 9.85 mg∙kg-1 (dw) for Ni and 181.33 ± 115.1 mg∙kg-1 (dw) for Zn. The transfer of trace metals was studied in spinach. The different parts of S. oleracea accumulate trace metals differently. Trace metals concentrations in the sediments and the chenopodiaceae are highly variable both spatially and temporally. Our results indicate that S. oleracea cοncentrates and sequesters Cd, Cu, and Ni in its roots, whereas Zn is translocated to leaves. The hierarchy of mean TM level in spinach (Zn &gt; Cu &gt; Ni &gt; Cd) is similar to that of sediments.