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This will be a second step of my final paper, which is literature review.
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It should be three pages in APA format
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The final paper is about THE IMPACT OF HUMAN ACTIVITY ON SOIL, I will attach different
articles that you will use for this literature review and also an experiment.
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Please avoid plagiarism.
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Make it as simple as you can.
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This paper worth 20% of my final grade.
This is a draft of the literature review portion of your paper. Using the references you
found how do you support what we did in the experiment. This should be between 2-3
pages at minimum. (Remember this should be 3 pages of your final paper)
Remember our overall question is what are the impacts of human activity on soil? Your
literature review will examine previous studies of human activities' impacts on soil.
Hindawi Publishing Corporation
Applied and Environmental Soil Science
Volume 2012, Article ID 619548, 2 pages
doi:10.1155/2012/619548
Editorial
Impact of Human Activities on Soil Contamination
Fernando José Garbuio,1 Jeffrey L. Howard,2 and Larissa Macedo dos Santos3
1 Departamento
de Ciência do Solo, Instituto Federal Catarinense, Santa Rosa do Sul, SC 48202, Brazil
of Geology, Wayne State University, Detroit, MI, USA
3 Department of Chemistry, Federal Technological University of Paraná, Pato Branco, PR, Brazil
2 Department
Correspondence should be addressed to Fernando José Garbuio, fgarbuio@yahoo.com.br
Received 17 December 2012; Accepted 17 December 2012
Copyright © 2012 Fernando José Garbuio et al. This is an open access article distributed under the Creative Commons Attribution
License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly
cited.
The impacts of human activities on soil contamination are
many and varied. The extent of human impact is now so pervasive and profound that there is currently much discussion
about the “Anthropocene”, a new geologic era characterized
by anthropogenic disturbances of the geologic record. Many
of the problems recognized during the 1970s linger on,
including the effects of acid rain and airborne deposition
of soot, fly ash, and other potentially toxic particulates.
Further, the scope of the problem has grown significantly
with economic growth in previously less developed nations
such as China and India. The effects of human activities vary
with land use, ranging from agricultural wastes such as farm
animal sewerage and fertilizer runoff, to commercial and
industrial wastes of every conceivable type and magnitude.
Over the years, the list of toxic contaminates has also grown,
so that it not only includes heavy metals, radionuclides,
and organic compounds of anthropogenic origin, but pharmaceuticals, explosives, and previously unknown biological
pathogens. The field of soil remediation has also grown
tremendously over the past few decades. The goal of this
special issue is to further explore the effects of human activities on soil contamination. Topics to be examined include
the nature and extent of soil contamination, state of the
art methodologies for studying soil and related groundwater
contamination, and innovative techniques for remediation.
This special issue initially contains five articles, with
plans for future publication of additional papers. The papers
deal with heavy metals and toxic organics, as well as soil
acidification and the effects of military explosives on soil. In
the paper “Occurrence of vanadium in Belgian and European
alluvial soils,” V. Cappuyns and E. Slabbinck bring attention
to the possible effects of V as a soil contaminant. They
document the nature and extent of V contamination in
alluvial soils developed in three industrialized drainage
basins in Belgium, and from other areas in Europe. Their
results suggest that the mobility of V is low, but nevertheless
worthy of further investigation. B. V. Kjellerup et al. examine
the effects of biodecomposition by bacteria as a remedial
tool for PCB contamination in the paper entitled “Spatial
distribution of PCB dechlorinating bacteria and activities
in contaminated soil.” Their results support the use of
the method for remediating sediments, whereas use in
contaminated soils faces further challenges. In the paper
called “Acidification and nitrogen eutrophication of Austrian
forest soils” R. Jandl et al. reevaluate the effects of acidic
deposition and nitrogen on forests soils. Interestingly, pH
has risen in the soils studied as a result of air pollution
mitigation and nitrate leaching into the groundwater is not
found to be a large-scale problem. The high levels of nitrogen
deposition have actually led to an unexpected increase in the
forest productivity. J. Pichtel reviews the effects of military
explosive wastes on soils in the article entitled “Distribution
and fate of military explosives and propellants in soil: a review.”
He shows that soils worldwide are contaminated by the
chemically active components of explosives and propellants.
These compounds undergo varying degrees of chemical
and biochemical transformation and appear to be common
groundwater contaminants. Thus, there appears to be an
urgent need to identify and remove such hazards from contaminated soils. In the paper “A critical evaluation of single
extractions from the SMT program to determine trace element
mobility in sediments,” V. Cappuyns compares two commonly
applied single extraction procedures, ammonium-EDTA and
acetic acid, for evaluating heavy metal contamination in
2
Applied and Environmental Soil Science
soils. The results underscore the difficulties of relating single
extractions to phytoavailability, and thus the need for further
work.
Fernando José Garbuio
Jeffrey L. Howard
Larissa Macedo dos Santos
Copyright of Applied & Environmental Soil Science is the property of Hindawi Publishing Corporation and its
content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's
express written permission. However, users may print, download, or email articles for individual use.
Environmental Polllution $6 (1994) 5 13
© 1994 Elsevier Science Limited
Printed in Great Britain. All rights reserved
0269-7491/94/$07.00
ELSEVIER
EFFECT OF SOIL pH ON AVAILABILITY TO CROPS
OF METALS IN SEWAGE S L U D G E - T R E A T E D SOILS. II.
C A D M I U M UPTAKE BY CROPS A N D IMPLICATIONS
FOR H U M A N DIETARY INTAKE
S. R. Smith
Water Research Centre, Henley Road, Medmenham, Marlow, Bucks, SL7 2HD, UK
(Received 24 November 1992; accepted 2 August 1993)
Abstract
Appropriate pH-related permissible soil-limit concentrations for cadmium in sewage sludge-treated agricultural
soils were estimated from the proportional changes in
concentrations of cadmium in potatoes, oats and ryegrass
grown on two sludge-amended soils and at different pH
values. Implications for potential human dietary intake of
cadmium were also assessed Yields of crops increased
with increasing soil pH, probably in response to decreasing uptake of zinc as soil pH value was raised In general cadmium concentrations in peeled potato tubers,
potato peelings, oat straw and ryegrass decreased as simple linear functions of increasing soil pH over the range
of pH values measured (pH 3.9-7.6). Cadmium concentrations in potato peel were particularly sensitive to
changing pH conditions, whereas cadmium levels in oat
grain were independent of soil pH. On the basis that a
highly precautionary approach is adopted in setting soil
standards for heavy metals, appropriate permissible concentrations of cadmium in sludge-treated agricultural soil
which protect the human food chain were determined as
2.0 and 2.5 mg Cd kg ~for banded pH ranges of 5.0-5.5
and 5.5~5.0, respectively.
INTRODUCTION
The agricultural use of sewage sludge provides environmental and economic benefits through recycling to soil
essential plant nutrients and also organic matter contained in the sludge. Such recycling to farmland is subject to regulation, however, to minimise risk to the
environment from potentially toxic elements (PTEs),
particularly heavy metals, which are also applied to soil
in sewage sludge, and maximum permissible concentrations of PTEs in soil have been established to prevent
environmental problems when sewage sludge is used in
agriculture (CEC, 1986; DoE, 1989; SI, 1989).
The permissible soil limits for the potentially phytotoxic metals nickel, copper and zinc are based on
precautionary estimates of upper critical soil concentrations of these elements from plant-yield assessments
(Davis & Carlton-Smith, 1984). In contrast, the development of soil limits for cadmium, a potentially
zootoxic element, requires a different approach. This is
because increased concentrations of such elements in
crop tissues may reach levels which could be toxic to
animals and man consuming them before detrimental
effects on plant growth occur. Consequently, the soil
limits for cadmium have been developed on the basis of
the potential impact on the human diet of increasing
cadmium concentrations in crops due to the application of sewage sludge to agricultural land.
Several human dietary surveys of cadmium intake resuiting from sludge application to agricultural soil have
been undertaken (Sherlock, 1983; Kampe, 1984). The
field experiments of Carlton-Smith (1987), in particular,
provide a quantitative estimate of potential human intake of cadmium from staple plant foods in relation to
cadmium concentrations in sludge-treated soil. This dietary model indicated that the cadmium intake of an
average consumer taking potatoes and other vegetable
plant foods only from sludge-treated soil, at the maximum permissible concentration of 3.0 mg Cd kg ~
(CEC, 1986), would be approximately 34 p.g day t for a
sandy loam at pH 6.5. This value is less than half the
recommended maximum tolerable intake of cadmium,
which has been set at 70 ~g Cd day ~ (WHO/FAO,
1972). Indeed, the dietary model showed that a soil
concentration of 6.0-12.0 mg Cd kg ~ was compatible
with the WHO maximum tolerable dietary intake. Also
a further margin of safety exists between this recommended value and the minimum intake which is
thought to cause kidney damage in the most sensitive
individuals at 200 p,g Cd day 1 for 50 years (US EPA,
1979).
It is almost inconceivable, however, that all the plant
produce consumed by an individual would be obtained
from the same area of sludge-treated land. Market
dilution factors would therefore substantially reduce
cadmium intakes below the amount calculated by
Carlton-Smith (1987). In addition, there is evidence
that metal availability to plants is increased following
single large applications of sludge, which are necessary
to increase the soil metal content under experimental
conditions in the field, compared with small, but repeated dressings applied operationally over a long
period of time (Chang et al., 1987). Similarly, CarltonSmith (1987) probably overestimated the availability to
6
S.R. Smith
crops of cadmium in sludge-treated soil compared with
the likely exposure occurring under operational conditions.
Soil pH value is the principal soil factor controlling
cadmium availability in soils (Davis & Coker, 1980;
Alloway, 1990) and decreasing soil pH value increases
cadmium uptake by crops. In the UK, The Sludge (Use
in Agriculture) Regulations (SI, 1989) and the Code of
Practice for Agricultural Use of Sewage Sludge (DOE,
1989) give maximum permissible concentrations of
nickel, copper and zinc according to banded soil pH
ranges of 5.0 < 5-5, 5-5 < 6.0, 6.0-7.0 and >7.0 which
implement the EC Directive on environmental protection when sludge is used in agriculture (CEC, 1986).
The limit values set for these elements in relation to soil
pH were confirmed by Smith (1994) in the first paper of
this series. However, no account of soil pH value is
currently taken in the U K Regulations for cadmium.
The purpose of this second phase of study was to
assess the uptake of cadmium from sludged soil by
potatoes and oats which represent staple food crops
that can yield satisfactorily at soil pH values as low as
5.0 (Archer, 1988) and may therefore be sensitive to
sludge-borne cadmium. Ryegrass was also included in
the study for comparison with the food crops. The
selected crops were grown under field conditions on
two soils of intrinsically low pH adjusted by liming to
provide a range of soil pH conditions. Results are
discussed in relation to human dietary intake of
cadmium from sludge-treated agricultural land.
MATERIALS AND M E T H O D S
Site selection
Two field sites were selected which had received past
applications of sewage sludge at Swinton, Greater
Manchester, and Harrogate, North Yorkshire, with
soils of intrinsically low pH (pH 4.4 and 5.1, respectively) with elevated concentrations of heavy metals
generally approximating to, or exceeding, the U K soil
limits (SI, 1989). A complete physico-chemical description of the soils is given by Smith (1994). However, the
background concentrations of cadmium in the soils,
which forms the subject of this investigation, were 9.1
mg kg -~ at Swinton and 2-77 mg kg -~ at Harrogate.
Lime application and cropping treatments
Lime was applied to the soils as ground calcium carbonate to achieve target pH values of pH 5.0, 5.5, 6.0
and 7-0 at Swinton in 1988. At Harrogate, ryegrass was
grown in an earlier trial commencing in 1985 with
target soil pH treatments of 5.3, 5-6, 6.0, 6.5, 7.0, 7.5
and 8.0. In the later study at Harrogate, which commenced in 1988, the number of pH treatments was reduced and lime was applied to an adjacent area of land
to achieve target soil pH values of 5.5, 6.0 and 7.0.
Control plots did not receive lime treatment. The necessary lime additions to the soils were estimated on the
basis of a laboratory incubation procedure. The incubation method and rates and timing of lime applica-
tions to the experimental plots are described by Smith
(1994).
Potatoes (Solanum tuberosum cv Pentland Crown),
spring oats (Arena sativa cv Rollow) and perennial ryegrass (Lolium perenne cv Melle) were grown at Swinton
on plots with dimensions of 4 m x 10 m, 4 m x 4 m
and 2 m x 1 m, respectively, arranged as a Latin
square for each crop. At Harrogate, potatoes and oats
were grown on plots with dimensions 3 m x 8 m and
2 m x 2 m, respectively, arranged in three randomised
blocks for each crop. Ryegrass was established at this
site on plots (2 m x 1 m) in a completely randomised
arrangement with four replicates per treatment. The
crops were grown at both sites for two successive years.
Cultural techniques
Following initial soil cultivations (Smith, 1994), potatoes were planted with a mechanical two-row planter in
ridged rows spaced 0.75 m apart, with an intra-row
spacing of 0.6 m, and at a depth of 0.2 m. Four rows
of potatoes were planted on the plots at Swinton,
whereas only two rows were planted at Harrogate.
Certified seed potatoes were used for the trials; they
had been screened to remove tubers with diameters
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