Soil-to-plant transfer of arsenic and phosphorus along a contamination gradient in the mining-impacted Ogosta River floodplain

Abstract

Riverine floodplains downstream of active or former metal sulfide mines are in many cases contaminated with trace metals and metalloids, including arsenic (As). Since decontamination of such floodplains on a large scale is unfeasible, management of contaminated land must focus on providing land use guidelines or even restrictions. This should be based on knowledge about how contaminants enter the food chain. For As, uptake by plants may be an important pathway, but the As soil-to-plant transfer under field conditions is poorly understood. Here, we investigated the soil-to-shoot transfer of As and phosphorus (P) in wild populations of herbaceous species growing along an As contamination gradient across an extensive pasture in the mining-impacted Ogosta River floodplain. The As concentrations in the shoots of Trifolium repens and Holcus lanatus reflected the soil contamination gradient. However, the soil-to-shoot transfer factors (TF) were fairly low, with values mostly below 0.07 (TF=As/As). We found no evidence for interference of As with P uptake by plants, despite extremely high molar As:P ratios (up to 2.6) in Olsen soil extracts of the most contaminated topsoils (0-20cm). Considering the restricted soil-to-shoot transfer, we estimated that for grazing livestock As intake via soil ingestion is likely more important than intake via pasture herbage.

Accumulation of Arsenic by Plants Growing in the Sites Strongly Contaminated by Historical Mining in the Sudetes Region of Poland

“…Such an effect was not reflected by the results of As extractability, determined in dried soil samples. Seasonal differences in As accumulation by plants growing in floodplain soils and the importance of soil moisture conditions were clearly documented by Simmler et al [39], similarly to the effects of soil moisture on As uptake by rice [8].…”

“…Translocation factor TF is a parameter that characterizes plant ability to transfer elements from roots to shoots. The values of TF calculated for all the plants growing in the study areas ranged broadly (0.004-26.8), though, they were generally very low (Figure 2), with a median 0.17, which is a typical feature for As [15,16,39,73,74].…”

“…An extreme case of that phenomenon is As-hyperaccumulating species [29,30], though, their natural occurrence was not reported from Europe. However, there are several reports on strong accumulation of As in plants growing in strongly polluted sites, in particular in those affected by mining activity, so that its concentrations in plant shoot tissues can be as high as tens, hundreds or even thousands mg/kg [15,[31][32][33][34][35][36][37][38][39].…”

Effect of NOM on copper sulfide nanoparticle growth, stability, and oxidative dissolution

“…Many floodplain and wetland areas around the world are contaminated with metals due to upland mine waste discharge or tailings dam failures. [1][2][3][4][5][6][7] Among those metals, copper (Cu) is an essential nutrient for all living organisms since it is required for the synthesis of numerous enzymes and proteins involved in redox-related biological functions. But its uptake is merely required in trace amounts.…”

Arsenic Uptake by Two Tolerant Grass Species: Holcus lanatus and Agrostis capillaris Growing in Soils Contaminated by Historical Mining

“…Arsenic belongs to potentially toxic elements that can be released into the environment from waste materials disposed in the sites of former or contemporary ore mining and processing [1][2][3][4][5][6][7]. In the Polish part of the Sudetes, a mountain range that stretches along the Polish-Czech border, there are three historical arsenic mining centers: Zloty Stok, Radzimowice and Czarnów [8,9], of which Zloty Stok is the largest one.…”