Introduction

Abstract

Modesto, Fabiana de Ávila. Evaluation of leachate characteristics from landfills in the state of Minas Gerais and analysis of natural wetlands as an alternative for post-treatment. 2021. 127 f. Dissertação (Mestrado Profissional em Rede

The impact of urban expansion and agricultural legacies on trace metal accumulation in fluvial and lacustrine sediments of the lower Chesapeake Bay basin, USA

“…On a spatial basis, lithological degeneration is the dominant factor in determining the total concentration of heavy metals in world soils. Sediments derived from formations composed of black shales, coals, limestones, ultramafic rocks and sedimentary ironstones are regularly enriched in several heavy metals, although content can vary (Alloway, 2013; Table 1). During weathering, these deposits undergo dissolution and oxidation, and metals are dispersed in regional soils, transported long distances via Aeolian or fluvial transport and/or leached into groundwater (Alloway, 2013;Sweet et al, 1989;Roen, 1984;Tuttle et al, 2009).…”

“…The pathways through which trace elements enter aquatic systems are diverse. Natural non-point sources like weathering of local geology and deposition of volcanic fallout provide significant inputs of trace metals via runoff or atmospheric deposition (Alloway, 2013). On a spatial basis, lithological degeneration is the dominant factor in determining the total concentration of heavy metals in world soils.…”

“…Decaying automobile parts and concrete contributes significantly to trace metal concentration as water flows through landscapes (Rice, 1999;Wang and Bjorn, 2014;Karuppiah and Gupta, 1998;Yesilonis et al, 2008). Agricultural sources of heavy metal pollution include the use and subsequent runoff of pesticides, fertilizers and biosolids as well as the rearing of livestock whose manure is enriched in trace metals (Alloway, 2013;Karuppiah and Gupta, 1998).…”

“…Point sources for metal pollution include municipal sewage discharges, power plant effluence, industrial releases, and acid mine drainage (Alloway, 2013;Andren et al, 1975). The disposal of mine tailings in proximity to aquatic systems correlates with environmental degradation (Odhiambo et al, 1996), eventually exacerbating the biological uptake of metals associated with mine waste (Axtmann and Luoma, 1991).…”

Spatial Distribution and Assessment of cadmium, nickel and lead within Soils of Sinnours, Fayoum, Egyopt

“…Gomah (2016) found that the using of some organic (Charcoal) and inorganic (Silica gel, Cement Bypass and Rock phosphate) materials reduced the DTPA extractable Cd, Ni and Pb from 0.895, 12.097 and 26.02 mgkg -1 in the control treatment to 0.376, 3.13 and 9.06 mg kg -1 , respectively. Cadmium is evidently found in soils at concentrations 0.1 -1 mg/kg (Alloway, 2013). Alternatively, Aydenalp and Gresser (2003) determined that the total Cd level in soils on calcareous material (marl materials) ranged from 0.23 to 0.51 mg/kg in Turkey and DTPA extractable Cd varied from 0.04 to 0.08 mg/kg.…”