Fig 1.
Schematic representation of the study area (an abandoned lead smelter, Santo Amaro, BA, Brazil) showing the location of the 11 sampling points along the two transects and of the three reference points.
Font: Julia Niemeyer.
Table 1.
Physico-chemical characteristics of the three groups of soils sampled at the Santo Amaro (BA, Brazil) study area and respective reference soils.
USDA–United States Department of Agriculture; CEC–Cation Exchange Capacity; WHC–Water Holding Capacity.
Table 2.
Total and extractable metal concentrations in the three groups of soils sampled at the Santo Amaro (BA, Brazil) study area and respective reference soils.
Table 3.
Number of juveniles of soil invertebrates, and plant shoot length and biomass (average ± standard deviation) in ecotoxicity tests for the assessed sampling points.
Asterisks indicate significant differences (* p<0.05; ** p<0.01; *** p<0.001) for a one-tailed hypothesis of a Dunnet’s test between each sampling point and the respective reference soil. In the ANOVA for E. andrei and for plants, soil organic matter was used as covariable. n—number of replicates.
Table 4.
Total number of individuals and morphospecies (shown in brackets) of surface dwelling invertebrates caught in pitfall traps (n = 3) at each 11 of the 13 sampling point.
Main Orders are presented individually while less abundant orders (Isopoda, Dermaptera, Hemiptera, Diplopoda,Mantodea and Opilionidae) were pooled and presented in a single group called Others. The values for the reference points were averaged to give an overall reference value. No data was obtained for Ref 3 sampling point due to the loss of all pitfall traps due to animal trampling.
Table 5.
Soil microbial parameters and organic material decomposition (mean ± standard deviation) for the assessed sampling points.
The values for the three reference points were geometrically averaged to give an overall reference value. Asterisks indicate significant differences (* p<0.05; ** p<0.01; *** p<0.001) for a one-tailed hypothesis of a Dunnet’s test between each sampling point and the overall reference value (assuming that Ref value higher than sampling point value and lower for Potential Nitrification). In the ANOVA for soil microbial parameters, soil moisture, soil organic carbon and soil nitrogen contents were used as covariables (data extracted from Niemeyer et al 2012a,b). n—number of replicates.
Table 6.
Individual and combined risk values from the chemical (ChemLoE) and ecotoxicological (EcotoxLoE) lines of evidence and the integrated risk (IR) for the soil retention function.
Table 7.
Individual and combined risk values from the chemical and ecotoxicological line of evidence (EcotoxLoE) for the soil habitat function.
Table 8.
Individual and combined risk values from the ecological line of evidence (EcolLoE) for the soil habitat function.
Fig 2.
Integrated ecological risk values for habitat function (+ standard deviation) (Min,0; Max, 1) for each sampling point, combining information from the chemical (ChemLoE), ecotoxicological (EcotoxLoE), and ecological (EcoLoE) lines of evidence.
Points with grey bars are located inside of the smelter area. Different bands indicate limits of accepted risk values for different soil uses (A agriculture, R residential, I industrial; asterisks indicate necessity of sealed soils) according to Jensen and Mesman (2006). Triangles on top of each bar represent the contribution of each LoE for the integrated risk value being an indicator of the weight of evidence (a triangle with equal sized arms (equilateral) indicates a similar risk value (high weight of evidence) for each LoE). The length of each “arm” of the triangle is proportional to the risk value for each LoE (on the top right the example with the length of each axis of the triangle representing maximum risk (1) from each LoE).