Heavy metal contents in soils and native flora inventory at mining environmental liabilities in the Peruvian Andes

Accumulation of As, Ag, Cd, Cu, Pb, and Zn by Native Plants Growing in Soils Contaminated by Mining Environmental Liabilities in the Peruvian Andes

“…The acidity of the soil and their unbalanced properties pointed to the poor soil management [42]. Santos-Francés et al [22] at Colquirrumi mine, located 6 km NW of our study area, reported acid soils (pH = 4.6), low organic matter content (5.04%), and silt sand texture (29.5% sand, 41.5 silt, and 30.8% clay); also, soils Colquirrumi are on quartzite and dacite substrates, which are much less reactive [39]. These results show significant differences in comparison with the study reported by Bech et al [43] for the Carolina Mine, located 4 km SW of the study area, which reported basic pH of soil (i.e., pH = 6.8-8.0), high calcium carbonates levels, slight electrical conductivity (0.1-0.8 dSm −1 ), and silt loam texture.…”

“…Copper concentrations significantly exceeded the maximum values allowed in both studied sites, and Ag was above the Canadian legal threshold only in samples from site #1 located furthest from the point of contamination (45 to 60 m). On the other hand, the Colquirrumi mine reported high content of heavy metals largely exceeding maximum allowed concentrations according to both PEQS and CSQG (Pb = 2069 mg kg −1 , Zn = 1893 mg kg −1 , Cu = 198 mg kg −1 , As = 428 mg kg −1 , and Cd = 13 mg kg −1 ) [22,39]. In addition, the Carolina mine, when it was an active mine in the same Hualgayoc district, reported high concentrations of Pb, Zn, Cu, and As (3992-16,060, 11,550-28,059, 256-2070, and 280-1030 mg kg −1 , respectively) [47].…”

“…In the texture of soils, the sand fraction dominated at 42-66% in site #1 and at 52-62% in site #2, varying from sandy clay loam to clay loam textures in the different layers. The mineralogical composition of soils was dominated by illite/sericite, kaolinite, quartz, and jarosite [39]. The most important factor affecting trace metals availability is soil pH [1], which usually increases the mobility and bioavailability of the metal with lower pH values, with the content of organic matter and clay minerals [10,40].…”

“…Following the initial screening of 34 elements [39], the study of Pb, Zn, As, Cu, Ag, and Cd was found of the highest interest because of their extremely high contents and potential toxicity. The results obtained for these elements for 15, 30, 45, and 60 m distances from the points of contamination at two different depths (0-15 and 15-30 cm) are presented in Figure 2a,b for sampling sites #1 and #2, respectively.…”

Recognition of Heavy Metals by Using Resorcin[4]arenes Soluble in Water

“…Examples of the above are those produced by Pb, which has effects on bacteria, and by Cd, which impacts the fungal population [5]. The fate and effect of these pollutants depend on the geographical and environmental conditions, the nature of the soil and the type of human activities, including the use of agrochemicals [6,7], mining [8][9][10][11] and industrial activities [12,13].…”