This document establishes quality reference values (QRV) for potentially harmful elements (PHE) in soils from the Atlantic Rainforest region of Brazil. Soil samples were collected from 63 sites across different soil types and parent materials in the region. The concentrations of 15 PHE were measured and background values were determined. QRVs, defined as the 75th percentile, were established for each PHE by soil order. The QRVs determined in this study were generally lower than international guidelines but some values, like for lead, were higher likely due to air pollution from vehicle traffic in the region. Establishing local QRVs will help environmental agencies more accurately assess anthropogenic impacts on the fragile Atlantic Rainforest ecosystem.
Reference values for potentially harmful elements in soils from Atlantic Rainforest, Brazil
1. Reference values for potentially harmful
elements in soils from
Atlantic Rainforest, Brazil
Eloana Janice Bonfleur
Vander Freitas Melo
Brenda Buschle
Luiz Claudio Paula Souza
3. Soils
Composition of the
parent material
SCOPE
e.g: PbS
Source: https://goo.gl/3N2351
Determination of a
guideline values for PHE to
differentiate natural and
anthropogenic
sources
considering the differences in
soil parent materials
Function
5. AIM
Determine the background values and quality reference
values for
Ag, As, Ba, Cd, Co, Cr, Cu, Mo, Ni, Pb, Sb, V e Zn.
The first study to determine quality reference values (QRV) for
PHE in Coastal Plain (Atlantic Rainforest) from Brazil;
• Atlantic Rainforest
greater diversity of wildlife and flora of the planet
its preservation begins with the determination of natural
background levels of organic and inorganic pollutants in
soils.
8. Materials and Methods
Orders:
Entisols: 1
Spodosols: 19
Inceptisols: 14
Aquic Alfisols: 22
Oxisol: 1
Ultisols: 6
Main Parent Materials:
Marine sediments
Fluvial deposition sediments
Colluvium deposits
Old alluvium
Gneiss-migmatite
Etc...
determined using the
geological and soil maps
63 sampling points
areas without or with
minimal human influence
(Atlantic Rainforest): observed
through aerial images
(Google Earth®).
15 geological conditions
0-0.2 m deep
Soils
9. Materials and Methods
Potentially harmful elements (PHE) in soils
• Acid digestion (microwave): HCl + HNO3
• Determination: atomic emission spectroscopy with plasma
coupled inductively (ICP-AES).
• DL = average concentration of 10 blank samples + 3s
where: s is the standard deviation of the readings.
10. Materials and Methods
QRV: Soil quality reference values for potentially harmful
elements (PHE) in soils
QRV determination: through percentile diagrams analyzes
(75 percentile)
Soil Order
12. Physical and chemical soil attributes
Descriptive
variables
pH
H2O
Sand Clay OC Na+
K+
Ca2+
Mg2+
Al3+ CEC
pH7
V
g kg-1
cmolc kg-1
%
Average 4.4 488 257 29.6 1.12 0.20 0.31 0.25 2.57 13.30 10.2
Median 4.4 497 233 20.2 0.08 0.12 0.15 0.12 1.88 11.00 4.7
Maximum 5.4 936 634 187.0 52.20 3.17 2.31 2.15 7.80 69.70 85.8
Minimum 3.3 2 23 6.1 0.03 0.03 0.07 0.01 0.09 2.15 2.0
Acid condition: reduces outer-sphere adsorption
increases solubility and mobility.
Strong influence of marine sediments.
13. Element Sand Clay Fe2O3CDBc
Ag -0.46* 0.46* 0.69*
As -0.71* 0.72* 0.57*
Ba -0.51* 0.53* 0.55*
Cd -0.63* 0.62* 0.82*
Co -0.05 0.05 0.15
Cr -0.35* 0.42* 0.64*
Cu -0.60* 0.55* 0.67*
Mo -0.32* 0.28* 0.09
Ni -0.47* 0.48* 0.66*
Pb -0.72* 0.66* 0.67*
Sb -0.45* 0.50* 0.72*
Se -0.23 0.29* 0.03
V -0.53* 0.54* 0.69*
Zn -0.68* 0.59* 0.57*
Importance of pedogenic iron oxides
(Fe2O3-CDB) on the contents of PHE
inner-sphere adsorption
H+ for Pb(OH)+ or 2H+ for Pb2+
Physical and chemical soil attributes
Tropical soils = high amounts of oxides
14. Potentially harmful elements (PHE) in soils
• The background levels (Atlantic Rainforest samples) of PHE in
the soils were highly lower compared to the international
standards (mg kg-1)
b Chen et al. (1991); c Salonen and Korkka-Niemi (2007); d Angelone and Bini (1992); e Dudka (1992); Dudka and Market (1992).
Element Mean Chinab
Irelandc
Italyd
USAb
Polande
Ag 0.4 10 - - - -
As 4.4 9.2 - - 5.2 2.6
Ba 70.8 - - - - 271.2
Cd 0.6 0.1 0.5 - 1.6 -
Co 0.2 - - - 20 3.6
Cr 44.2 53.9 49.5 100 37 16.8
Cu 12.1 20 16.9 51 17 6.3
Mo 1.6 1.2 - - 0.6 -
Ni 13.5 23.4 13.5 46 13 7.4
Pb 10.4 23.6 30.4 21 16 18.8
Sb 3.4 - - - - -
Se 1.4 - - - - 0.1
V 37.1 - - 87 - 18.4
Zn 30.4 67.7 70.3 89 48 40.3
Effect of
weathering or
pedogenesis?
15. • Intense human occupation;
• dispersion of pollutants by air;
• it must be consider the heavy traffic on the
roads (Pb emissions).
The background levels (Atlantic Rainforest samples) of Pb
was higher compared to
Element Mean MGf
ESg
MT/ROh
PEi
PIj
ORl
Pb 10.4 3.9 8.8 8.1 11.2 5.9 18
f Souza et al. (2015).; g Paye et al. (2010).; h Santos and Alleoni (2013).; i Biondi et al. (2011).; j Paula Filho et al. (2015);. k Lima et al. (2016).
the other Brazilian states
Potentially harmful elements (PHE) in soils
16. QRV for PHE in soils (mg kg-1)
Ag As Ba Cd Co Cr Cu Mo Ni Pb Sb V Zn
P 75 0.29 4.78 111.4 1.02 <0.17 48.7 17.8 1.44 17.2 16.9 3.12 60.2 52.5
MGa
- 8.00 - <0.40 - 75.0 49.0 - 21.5 19.5 - - 46.5
ESb
- <12.83 - <0.13 10.20 54.1 5.9 1.74 9.1 <4.5 - - 29.8
RO/MTc
- 0.44 - <0.30 21.30 44.8 20.6 - 2.1 9.0 - - 3.0
SPd
0.25 3.50 75.0 <0.50 13.00 40.0 35.0 <0.40 13.0 17.0 <0.50 275.0 60.0
PVe
2.00 15.00 150.0 1.30 25.00 75.0 60.0 30.00 30.0 72.0 2.00 - 300.0
Other Brazilian States
QRV for Paraná Coastal Plain
X
• Pedogenetic factors;
• digestion techniques
HF
x
HCl+HNO3
Great diferences
17. Ag As Ba Cd Co Cr Cu Mo Ni Pb Sb V Zn
QRV 0.29 4.78 111.4 1.02 <0.17 48.7 17.8 1.44 17.2 16.9 3.12 60.2 52.5
MGa
- 8 - <0.4 - 75.0 49.0 - 21.5 19.5 - - 46.5
ESb
- <12.83 - <0.13 10.21 54.1 5.9 1.74 9.1 <4.5 - - 29.8
RO/MTc
- 0.44 - <0.3 21.3 44.8 20.6 - 2.1 9.0 - - 3.0
SPd
0.25 3.5 75 <0.5 13 40.0 35.0 <0.4 13.0 17.0 <0.5 275.0 60.0
PVe
2.00 15 150 1.3 25 75.0 60.0 30.0 30.0 72.0 2.00 - 300.0
Brazilian environmental agency
(CONAMA)
• yellow striping applied to road
pavements and lubricant in
automotive brake and clutch
linings.
Values below
QRV for PHE in soils (mg kg-1)
18. Conclusions
• The local determination of QRV will increase the quality and
accuracy of the intervention of environmental agencies;
• The relatively high average guideline values found in the
Atlantic Rainforest soils may promote excessive anthropic
activities in this fragile environment.
The dispersion of air pollutants from vehicles increased PHE background in
plain soils