Chemical speciation of copper and manganese in solution of a copper-contaminated soil and young grapevine growth with amendment application

doi:10.1016/j.pedsph.2022.06.060

Pedosphere

Volume 33, Issue 3, June 2023, Pages 496-507

https://doi.org/10.1016/j.pedsph.2022.06.060 Get rights and content

Abstract

Copper (Cu)-based fungicide application to control foliar diseases in grapevine (Vitis vinifera L.) can increase soil Cu availability. Brazilian soils have high natural Cu and manganese (Mn) concentrations, increasing the potential for toxicity to grapevine plants. Application of amendment substances can reduce the concentrations of toxic chemical species of Cu and Mn in soil solution, especially for the soils grown with young plants. We evaluated the chemical speciation of Cu and Mn in soil solution and young grapevine growth using a contaminated soil with amendment application. Grapevine seedlings of Paulsen 1103 rootstock were grown for 12 months on an old vineyard (> 30 years of cultivation) soil without (control) and with vermicompost or limestone application. Grapevine dry matter, root morphological characteristics, and plant tissue Cu and Mn concentrations were evaluated. The cation and anion concentrations, dissolved organic carbon, pH, and chemical speciation of Cu and Mn in soil solution from different soil layers were analyzed. Vermicompost application did not reduce Cu and Mn phytotoxicity, and grapevine plants died after winter pruning. High soluble Mn concentration in soil (5.56 mg L^–1 in 0–45 cm soil layer) and Mn concentration in plant tissue at pruning (380.8 mg kg^–1) might be the primary cause of plant death. Limestone application reduced Cu²⁺ and Mn²⁺ chemical species in soil solution, thereby increasing plant growth. The Cu²⁺ and Mn²⁺ species were negatively correlated (P < 0.05) with grapevine shoot production at pruning (r = –0.92 and –0.97, respectively) and at the end of the trial (r = –0.73 and –0.51, respectively). Limestone application increased grapevine shoot and root dry matter production by 36% and 41%, respectively, while also presenting the highest root length and volume in the 5–10 cm soil layer. Limestone application is a viable and profitable alternative for reducing soil Cu and Mn availability and their phytotoxic effects.

Section snippets

INTRODUCTION

Heavy metals naturally occur in soils, and some of them, such as copper (Cu) and manganese (Mn), can be introduced into the environment by anthropogenic activities, increasing the concentrations of these elements in different ecosystems (Kabata-Pendias, 2011). Heavy metals share similar chemical properties and can be toxic to cultivated plants, but the magnitude of their effects depends on several interactions once they coexist in the same environment. Therefore, discerning the chemical species

Experimental design

For this study, we collected soil samples from the 020 cm layer in an old vineyard (> 30 years of cultivation) located in the south of Brazil (30°47’34.5” S, 55°22’5.5” W). Over the years, the vineyard received a cumulative amount of approximately 30 kg Cu ha^–1 through foliar application of fungicides for preventive control of fungal diseases (Miotto et al., 2014). The soil was classified as Argissolo Vermelho (Embrapa, 2018), corresponding to an Ultisol (Soil Survey Staff, 2014). The soil

Plant growth under soil amendments

The greatest shoot dry matter (before and after pruning) and root dry mass production were observed in plants grown in the soil with limestone application (Fig. 1a, b). In this treatment, the shoot dry matter production before pruning was 72% and 46% higher than that in the vermicompost treatment and the control, respectively (Fig. 1a). After winter pruning, plants grown in the soil with vermicompost application did not sprout. Plants grown in the soil with limestone application increased the

DISCUSSION

Greater grapevine shoot and root dry matter production in the limestone treatment must have occurred in response to the increased soil pH. Higher soil pH promotes the deprotonation of surface acidic functional groups from SOM and clay minerals, increasing soil CEC and thereby Cu and Mn adsorption (Joris et al., 2012; Trentin et al., 2019). This, in turn, reduces their availability in the soil solution (Brunetto et al., 2016) and phytotoxic effects on plants (Ambrosini et al., 2015). Moreover,

CONCLUSIONS

Limestone application, a viable and profitable strategy to reduce Cu and Mn phytotoxicity to young Paulsen 1103 rootstock grapevine plants during initial development in acidic soils with high Cu and Mn concentrations, reduced Cu²⁺ and Mn²⁺ free species in the soil solution and favored plant root growth while reducing Cu and Mn absorption by grapevine seedling shoots, which highlights its efficiency in alleviating the phytotoxic effects of Cu and Mn on young grapevines. Vermicompost application

ACKNOWLEDGEMENT

The authors are grateful to the Conselho Nacional de Desenvolvimento Científico e Tecnológico (Brazilian National Council for Scientific and Technological Development, e CNPq) (No. 408318/2018), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES, Brazilian Federal Agency for Support and Evaluation of Graduate Education), Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul (Foundation for Research Support of the State of Rio Grande do Sul, Brazil), and FAPERGS (No.