Copper availability assessment of Cu-contaminated vineyard soils using black oat cultivation and chemical extractants

Abstract

Grapevines grown on acid soils with low fertility in southern Brazil are treated with intense foliar applications of copper (Cu) fungicides, resulting in an increased level of Cu in the soil and increased toxicity. The present study evaluated the accumulation and bioavailability of Cu, and soils with varying levels of Cu from the main producing regions of southern Brazil were collected. The forms of Cu present in the soil were assessed using chemical extractants; additionally, oat cultivation was performed, reflecting the use of the plant as an indicator of Cu bioavailability. Cu accumulated in the topsoil, mainly in bioavailable forms, and there was also an increase of Cu up to a depth of 0.4 m. Cu was primarily found in the mineral fraction, with apparent saturation of the soil organic matter functional groups. Inceptisol and Alfisol soils with a long history of cupric fungicide application were found to have levels of Cu toxic to oat plants. Furthermore, accumulated copper in Alfisol soil from the Campanha Gaúcha region of the state of Rio Grande do Sul had higher bioavailability compared to Cu accumulated in Inceptisol soil from the Serra Gaúcha region. In addition, the copper concentration in roots was found to serve as an indicator of Cu bioavailability in soil, but not of copper phytotoxicity in plants.

Intercropping of young grapevines with native grasses for phytoremediation of Cu-contaminated soils

“…This result indicates that mineral and organic Cu adsorption sites were saturated by dose 40 and 80. This was also described by Girotto et al (2014) and De Conti et al (2016). The increase in Cu content in the soil solution shows the low sorption capacity of sandy soils and the high toxicity potential for plants.…”

Germinação de espécies forrageiras na presença de cádmio, cobre e chumbo

“…O comprimento radicular é parâmetro importante quando da avaliação do efeito do elemento-traço, pois, a radícula é o primeiro órgão da plântula que entra em contato com a solução contaminada (FENG et al 2016). Em estudos com áreas contaminadas com Cu, GIROTTO et al (2014) observaram reduções de matéria seca tanto da raiz quanto da parte aérea e clorose internerval para Avena stringosa.…”

Fruit Characteristics of Citrus Trees Grown under Different Soil Cu Levels

“…Currently, copper (Cu) pesticides have been widely used to control citrus canker, blackspot, termite brown spot, and fruit drop after flowering [ 4 ]. However, only a small amount of the sprayed Cu fungicides could be absorbed by trees, while the remaining fungicides are washed and dropped into the soil by rain [ 5 , 6 ], precipitated in the soil [ 7 ], and finally result in Cu accumulation in citrus orchards soil year after year [ 8 , 9 ]. For instance, soil available Cu concentrations of a Brazilian cocoa plantation has reached 600 mg kg −1 after 16 years of application of Cu fungicides [ 10 ].…”