Soil contamination by heavy metals in vineyard of a semiarid region: An approach using multivariate analysis

Abstract

Contamination of vineyard soils by the continuous use of cupric fungicides and fertilizers has been a worldwide concern. The objective of this study was to determine the total concentration of Cu, Zn, Fe, Mn, Ni and Pb from vineyard soils of a semiarid region in Brazil. Soil samples at 0-20 and 20-40 cm depth were collected in areas under 5, 6, 8, 10, 12, 15, 16 and 30 years of cultivation, and compared with native vegetation areas. Samples were digested and total metal concentrations were determined by atomic absorption spectrophotometer. In general, concentrations of Mn, Ni, Fe and Pb were similar to those values found in the reference area, being regarded as background concentrations. On the other hand, Zn and Cu were mainly derived from the widespread use of fertilizers (e.g., phosphate application) and cupric fungicides, respectively. Discriminant analysis clearly demonstrated higher metal accumulation in surface soil samples, chiefly Zn and Cu owing to Zn and Cu-containing chemicals and accumulation of organic matter. This tool was also useful to differentiate between natural and anthropogenic inputs of metals into soils. The high enrichment factor values for Cu and Zn showed that both were mainly derived from anthropogenic sources.

Investigation of heavy metal accumulation in soil, water and plants in areas with intensive horticulture

“…Although there is no regulation that stipulates the natural level of this element in soil, a comparison with reference levels indicates a rise in anthropic Mn, given that the metal levels in forest soil are around 10 times lower than those of agricultural soils. The high Mn content corroborates a number of studies (Ramalho et al, 2000;Fernandes et al, 2007;Biondi et al, 2011;Preston et al, 2016), showing the need for legislation governing the Quality Reference Value of this metal in soil and plants. Table 2 shows the properties of planted soils that are most associated with the heavy metals studied.…”

Determination of heavy metals and lead strontium isotope characterization from Merlot soil samples, Dealu Bujorului vineyard

“…Nickel is an element found in soil and is highly dependent on the content of the parent rock material and climatic conditions, meaning that, in soil of arid and semiarid regions, its amounts are higher [14]. The total content of Ni showed significant positive correlation with the organic matter from soil surface (0-20 cm depth) which indicate that the organic matter on the first layer of the cultivated soil contribute to Ni retention in the soil [9]. Nickel may be removed by some cultures or by leaching to deeper layer in the soil profile and this could justify the reduction of this element in some areas given its high mobility [15,16].…”

“…Viticulture is an intensive practice, so the phytopharmaceuticals and chemical fertilizers are the main source of elemental pollution [5]. In vineyard areas, the use of fungicide based on Cu in their composition pollute the soil by accumulation in high concentrations in worldwide grapevine areas [6][7][8][9]. Vines and other plants have the capacity to tolerate Cu in excess.…”

Soil fertility changes in vineyards of a semiarid region in Brazil

“…(Silva et al, 2014). These changes can affect both crop yield and the quality of the soil environmental (Fernández-Calviño et al, 2010;Wightwick et al, 2013;Duplay et al, 2014;Silva et al, 2014;Brunori et al, 2016;Preston et al, 2016), resulting in either improvement of the soil properties or accelerated soil degradation (Jiao et al, 2012).…”

“…Furthermore, the widespread use of phosphate fertilizers and cupric fungicides has increased the concentration of trace elements in vineyard soils, leading to transfer of these elements at toxic levels to humans and animals via the food chain (Fernández-Calviño et al, 2012;Wightwick et al, 2013). These changes become more evident as the length of the cultivation time in the area increases (Preston et al, 2016). The concern is even greater for sandy soils due to their very low adsorption capacity for ions and pesticides.…”