Copper and zinc fractions in the profile of an Inceptisol cultivated with apple in southern Brazil

Abstract

The present study aimed to evaluate the accumulation and distribution of Cu and Zn fractions in the profile of an Inceptisol by application of fungicides with a previous history of apple cultivation in southern Brazil. Stratified soil samples (0.

Heavy Metal-Based Fungicides Alter the Chemical Fractions of Cu, Zn, and Mn in Vineyards in Southern Brazil

“…Among these clay minerals, we can mention the OH group of kaolinite; oxides of Fe, Al, and Mn; oxyhydroxides and hydroxides; and amorphous silicates [50]. Similar results have been observed by other authors in Southern Brazil [10,51]. The Zn present in the Zn Min and Zn Res fractions has low mobility and a low potential for toxicity to grapevines and cover crop species that cohabit the vineyards [7] In the soils of Campanha Gaúcha, which have low SOM contents, the mineral fraction is very important to retaining this metal since there has been an increase in Zn levels in this fraction over the years of vineyard cultivation.…”

“…The observed difference between the two regions is associated with the types of soils found in these locations. The Serra Gaúcha region presents a predominance of fertile soils, with organic matter content ranging from medium to high and with higher clay contents [18], leading to the increased adsorption of these elements in the soil's colloidal system, thus reducing the potential for transfer to the environment [10,47]. In contrast, the soils of the Campanha Gaúcha region have a sandy texture, a predominance of 1:1 clay, low organic matter content, and low natural fertility [18,19].…”

“…In the presence of high Cu content, Zn remains mainly adsorbed on the functional groups of the mineral fraction as iron oxides and at the edges of phyllosilicate clay minerals [61]. Such a feature can minimize the environmental contamination potential of Zn in the soil but also reduce its toxicity in plants, for example, in grapevines or even in implanted soil cover species or in species coexisting in vineyards [7,10]. However, Zn has migrated to the deepest layers (0.10-0.40 m), and it has mainly increased in the Zn Res fraction.…”

Copper and zinc transfer limits to soil solution of mixtures containing different clay and organic matter contents

“…Soil mixtures with higher clay content and lower SOM content desorbed higher amounts of Zn to water and smaller amounts to those with lower clay content and higher SOM content. This is because Zn usually has higher binding a nity to functional groups of the mineral solid phase of the soil (Brunetto et al, 2017;Brunetto et al, 2018). However, a considerable part of Zn can also be adsorbed to functional groups of the organic phase (Fernández-Calviño et al, 2012;Tiecher et al, 2017;Tiecher et al, 2018;Somavilla et al, 2018).…”

“…However, it is di cult to assess the exact change-point, which indicates the beginning of the rapid increase in Cu and Zn contents transported to water in response to Cu and Zn addition to soils. For instance, these heavy metals may come from animal waste applied to the soil surface in cropping systems (Da Rosa et al, 2018), from fungicides applied to crops to control foliar fungal diseases in vineyards and apple orchards (Brunetto et al, 2016;Brunetto et al, 2018;Marastoni et al, 2019) or even in soils where ores have been mined (Salnikova et al, 2018;Aihemaiti et al, 2018). This is also dependent on other variables, such as the strong interactions of Cu and Zn with the mineral and biological constituents of the soil, which boost transport to waters (Paluch et al, 2018).…”