Impacts of Phosphate Amendments at a Contaminated Site

2019 ◽  
pp. 90-100
Author(s):  
Kanchan P. Rathoure
Keyword(s):  
Toxic Metals ◽  
Contaminated Soils ◽  
Cell Walls ◽  
Phosphate Rock ◽  
Surface Soil ◽  
Contaminated Site ◽  
Residual Fraction ◽  
Subsurface Soil ◽  
Metal Immobilization ◽  
Soil Subsurface

Soil amendments can be used to cost-effectively reduce the bioavailability and mobility of toxic metals in contaminated soils. Phosphate amendments effectively can be transformed to soil from the non-residual (sum of exchangeable, carbonate, Fe/Mn, and organic) to the residual fraction. Metal immobilization can be attributed to the metal-induced formation of chloropyromorphite which can be identified in the surface soil, subsurface soil, and plant rhizosphere soil. Phosphate treatments can significantly reduce metal translocation from the roots to the shoots in the plants/crops possibly via the formation of chloropyromorphite on the cell walls of roots. Application of combined H3PO4 with phosphate rock can be provided an effective alternative to the current phosphate remediation technologies for contaminated soils.

Changes in soil solution composition and aluminium speciation under legume based pastures in response to long term phosphate fertiliser applications

Soil Research ◽  
1996 ◽  
Vol 34 (6) ◽  
pp. 985 ◽  
Author(s):  
V Manoharan ◽  
P Loganathan ◽  
RL Parfitt ◽  
RW Tillman
Keyword(s):  
Soil Solution ◽  
Phosphate Rock ◽  
Surface Soil ◽  
Solution Ph ◽  
Single Superphosphate ◽  
Phosphate Fertiliser ◽  
Reactive Phosphate Rock ◽  
Subsurface Soil ◽  
Aluminium Speciation

This study describes some of the effects of 8 years of annual application of 6 types of phosphatic fertilisers on the chemical composition and aluminium (Al) speciation in soil solution extracted from a soil under pasture. Soil samples at 2 depths, 0-30 and 30-75 mm, were collected at the end of 8 years. Soil solutions were extracted by centrifuging at 12 000 RCF and analysed for Al, Na, K, Ca, Mg, F, NO3, Cl, and SO4, as well as pH and ionic strength. Soil and soil solution pH were significantly increased at both depths by application of North Carolina phosphate rock (NCPR) compared with the control. In contrast, diammonium phosphate (DAP) significantly decreased the soil and solution pH. Single superphosphate (SSP) did not have any significant effect on soil or solution pH compared with the untreated control. The surface soil (0-30 mm) solution pH was on average 0.6 of a unit higher than the subsurface soil (30-75 mm) solution pH. Total monomeric Al concentration [Al], measured by the pyrocatecol violet (PCV; 4 min) method, ranged from 1.5 to 4.8 �M in the surface soil and 2.5 to 12.2 �M in the subsurface soil. The DAP and higher rates of SSP application resulted in a large increase in total and inorganic monomeric [Al] in the soil solution extracted from the subsurface soil. Total soluble [F] ranged from 2.7 to 23.5 �M and 3.2 to 25.6 �M in the surface and subsurface soils, respectively, and was significantly increased by the application of NCPR and by higher rates of SSP. The predominant forms of inorganic monomeric Al present in the soil solution were estimated to be the non-phytotoxic Al-F complexes, AlF2+, and AlF2+. There was a marked decrease in toxic Al species (Al3+, Al(OH)2+, Al(OH)2+) in soil solution following NCPR and SSP application. This was due primarily to complexation of Al with F derived from these fertilisers forming non-toxic AI-F complexes. The results suggest that the long-term application of reactive phosphate rock such as NCPR may contribute to amelioration of soil acidity and Al toxicity under legume-based pastures. In contrast ammonium-containing phosphate fertilisers such as DAP probably decrease soil pH and increase the formation of toxic Al species in the soil solution.

Immobilization of Pb, Cu, and Zn in a Multi-Metal Contaminated Soil Amended with Triple Superphosphate Fertilizer and Phosphate Rock Tailing

2011 ◽  
Vol 356-360 ◽  
pp. 1716-1718 ◽  
Author(s):  
Yuan Liang ◽  
Xiao Chun Wang ◽  
Xin De Cao ◽  
Ling Zhao
Keyword(s):  
Contaminated Soil ◽  
Contaminated Soils ◽  
Phosphate Rock ◽  
Treatment Effectiveness ◽  
Soil Profiles ◽  
Triple Superphosphate ◽  
Soil Columns ◽  
Untreated Soil ◽  
Subsurface Soil ◽  
Cu And Zn

The objective of this study is to immobilize Pb, Cu, and Zn in a multi-metal contaminated soil using triple superphosphate fertilizer (TSP) and phosphate rock tailing (PR) materials, alone and in combination. The treatment effectiveness was evaluated with a column leaching experiment under simulated rainfall conditions. More than 90% of Pb and Cu were stabilized in the upper layer soil (0-10cm) in both untreated and P-treated soil columns. However, the significant downward migration of Zn was observed in either untreated or P-treated column soil profiles though the transport was inhibited by P treatments. In the untreated soil, 27.2% of Zn migrated down to the subsurface soil (10-20cm), while there were 7.45%, 13.0%, and 11.2% of Zn transported down in the TSP, PR, and PR+TSP treatments, respectively. Phosphate reduced the leaching of Pb and Cu from the contaminated soils, with reduction of Pb and Cu in the leachate by up to 71.2% and 34.8%, respectively. However, Zn leaching was enhanced by P treatments except for TSP. The results indicated that triple superphosphate fertilizer and phosphate rock tailing were effective in immobilizing Pb followed by Cu, but less for Zn in a multi-metal contaminated soil.

scholarly journals Application of Biochar Produced from Crop Residues on Trace Elements Contaminated Soils: Effects on Soil Properties, Enzymatic Activities and Brassica rapa Growth

Agronomy ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1394
Author(s):  
Paloma Campos ◽  
Heike Knicker ◽  
Rafael López ◽  
José María De la Rosa
Keyword(s):  
Heavy Metals ◽  
Trace Elements ◽  
Rice Husk ◽  
Contaminated Soils ◽  
Crop Residues ◽  
Acidic Soil ◽  
Residual Fraction ◽  
High Concentration ◽  
Polluted Soils ◽  
Metal Immobilization

Soil pollution by trace elements is a huge problem around the globe. In addition, heavy metal immobilization and primary productivity are two soil ecosystem services of contemporary importance to society. The goal of this study was to evaluate the effects of using olive pit and rice husk biochars as soil amendments for the immobilization of trace elements and on plant development growing in heavy metals-polluted soils under greenhouse conditions. The application of high doses (5% and 10%) of biochar significantly increased pH, water holding capacity and total C content of the soils. Dehydrogenase activity in the moderately acidic soil was greater than in the acidic soil due to the high concentration of metals and high acidity of the latter. The application of biochar reduced the β–glucosidase activity. Furthermore, the concentrations of CaCl2-extractable heavy metals significantly decreased in biochar amended pots, indicating metal immobilization, which was consistent with the increase in soil pH. Distribution of trace elements in the different fractions was modified after 65 days of incubation, independently of the treatment. The Cu and Zn contents in the oxidizable fraction were reduced with incubation, whereas Cd and Zn in the residual fraction increased. The reduction of bioavailable concentrations and increments in the residual or more stable fractions indicated less risk for the organisms in the environment. All biochars addition significantly increased the root-to-shoot ratio compared to the control soil. Particularly, 10% of amendment increased this ratio in the greatest extent. The application of 10% w/w of rice husk biochar produced at 500 °C was the most effective in restoring soil functionality and reducing the availability of heavy metals in the polluted soils.

The agronomic effectiveness of reactive phosphate rocks 1. Effect of the pasture environment

1997 ◽  
Vol 37 (8) ◽  
pp. 921 ◽  
Author(s):  
P. W. G Sale ◽  
R. J. Gilkes ◽  
M. D. A. Bolland ◽  
P. G. Simpson ◽  
D. C. Lewis ◽  
...  
Keyword(s):  
North Carolina ◽  
Phosphate Rock ◽  
Surface Soil ◽  
Annual Rainfall ◽  
Triple Superphosphate ◽  
Agronomic Effectiveness ◽  
P Sorption ◽  
Reactive Phosphate ◽  
Reactive Phosphate Rock ◽  
Very High

Summary. The agronomic effectiveness of directly applied North Carolina reactive phosphate rock was determined for 4 years from annual dry matter responses at 26 permanent pasture sites across Australia as part of the National Reactive Phosphate Rock Project. Fertiliser comparisons were based on the substitution value of North Carolina reactive phosphate rock for triple superphosphate (the SV50). The SV50 was calculated from fitted response curves for both fertilisers at the 50% of maximum yield response level of triple superphosphate. The reactive phosphate rock was judged to be as effective as triple superphosphate in the 1st year (and every year thereafter) at 4 sites (SV50 >0.9), and was as effective by the 4th year at 5 sites. At another 9 sites the reactive phosphate rock was only moderately effective with SV50 values between 0.5 and 0.8 in the 4th year, and at the final 8 sites it performed poorly with the 4th year SV50 being less than 0.5. Pasture environments where the reactive phosphate rock was effective in the 1st year were: (i) those on sandy, humic or peaty podsols with an annual rainfall in excess of 850 mm; (ii) those on soils that experienced prolonged winter inundation and lateral surface flow; and (iii) tropical grass pastures in very high rainfall areas (>2300 mm) on the wet tropical coast on North Queensland. The highly reactive North Carolina phosphate rock became effective by the 4th year at sites in southern Australia where annual rainfall exceeded 700 mm, and where the surface soil was acidic [pH (CaCl2) <5.0] and not excessively sandy (sand fraction in the A1 horizon <67%) but had some phosphorus (P) sorption capacity. Sites that were unsuitable for reactive phosphate rock use in the medium term (up to 4 years at least) were on very high P-sorbing krasnozem soils or high P-sorbing lateritic or red earth soils supporting subterranean-clover-dominant pasture, or on lower rainfall (< 600 mm) pastures growing on soils with a sandy A1 horizon (sand component >84%). No single environmental feature adequately predicted reactive phosphate rock performance although the surface pH of the soil was most closely correlated with the year-4 SV50 (r = 0.67). Multiple linear regression analysis found that available soil P (0–10 cm) and the P sorption class of the surface soil (0–2 cm), together with annual rainfall and a measure of the surface soil"s ability to retain moisture, could explain about two-thirds of the variance in the year-4 SV50 . The results from this Project indicate that there are a number of specific pasture environments in the higher rainfall regions of Australia where North Carolina reactive phosphate rock can be considered as an effective substitute P fertiliser for improved pasture.

scholarly journals Cadmium Bioaccumulation in Yellow Foxtail (Setaria glauca L. P. Beauv): Impact on Seed Head Morphology

2004 ◽  
Vol 3 (1) ◽  
Author(s):  
D Kosma ◽  
J Long ◽  
S Ebb
Keyword(s):  
Contaminated Soils ◽  
Significant Negative Correlation ◽  
Head Length ◽  
Contaminated Site ◽  
Seed Head ◽  
Setaria Glauca ◽  
Cadmium Bioaccumulation ◽  
Head Morphology ◽  
The Impact ◽  
Water Extractable

Yellow foxtail (Setaria glauca L. P. Beauv) growing on a cadmium-contaminated site was sampled to determine the extent of cadmium bioaccumulation in aerial tissues and the impact of cadmium on growth and development. Water-extractable Cd concentrations in the soil ranged from 5.0 to 18.0 mg L-1. Aerial tissues contained elevated concentrations of Cd (16-48 μg g-1 DW), with mean concentration ratios of >3.0. Since foxtail frequently colonizes disturbed sites, the bioaccumulation of Cd in aerial tissues of foxtail suggests that wildlife feeding upon this plant species could be exposed to elevated Cd levels. A significant negative correlation (r2=0.98) was observed between water-extractable Cd in the soil and seed head length in foxtail, indicative of an adverse effect of Cd on reproductive development. This correlation further suggests seed head length as a biomarker for soluble Cd in contaminated soils. KEYWORDS: Cadmium, bioaccumulation, biomarker, phytotoxicity

scholarly journals Heavy and Toxic Metals in Staple Foodstuffs and Agriproduct from Contaminated Soils

2003 ◽  
Vol 38 (2) ◽  
pp. 181-192 ◽  
Author(s):  
A. V. Gorbunov ◽  
M. V. Frontasyeva ◽  
A. A. Kistanov ◽  
S. M. Lyapunov ◽  
O. I. Okina ◽  
...  
Keyword(s):  
Toxic Metals ◽  
Contaminated Soils

Slow pyrolysis pine wood-derived biochar reduces nitrous oxide production from surface but not subsurface soil

2021 ◽  
Author(s):  
Hongyuan Deng ◽  
Leanne Ejack ◽  
Shamim Gul ◽  
Shiv Prasher ◽  
Joann K. Whalen
Keyword(s):  
Nitrous Oxide ◽  
Surface Soil ◽  
Sandy Loam ◽  
Pore Space ◽  
Limiting Factor ◽  
N Availability ◽  
Nitrogen Transformations ◽  
N2o Production ◽  
Pine Wood ◽  
Subsurface Soil

Soil amended with biochar is expected to produce less nitrous oxide (N2O), although this may depend on nitrate (NO3-N) availability. Our objective was to determine how pine wood biochar, slow pyrolyzed at 500°C, affects N2O production in soil having different denitrification potentials with variable NO3-N concentrations under controlled laboratory conditions. Sandy loam surface soils (0–30 cm, pH 5.7) and sandy clay loam subsurface soils (40–60 cm, pH 5.6) were amended with four biochar rates (0, 10, 20, and 30 g kg-1), two nitrogen fertilizer rates (0 and 100 mg kg-1 NO3-N) and two acetylene levels (0 and 10% headspace), arranged as a full factorial. Soil moisture content was adjusted to 80% water-filled pore space and flasks were incubated at 20°C for 30 h. Headspace gas was collected from each flask at 25, 26, 28 and 30 h. There was a significant reduction in N2O production with increasing rate of biochar in the surface soil but not in the subsurface soil. On average, less N2O was produced in the subsurface soil than the surface soil. As the NO3-N concentration was not a limiting factor for denitrification, the most likely explanation was that denitrifier activity was influenced by the availability of soluble organic carbon in the soil-biochar mixtures. We recommend further study of the coupled carbon-nitrogen transformations during denitrification to understand how biochar influences soil N2O production in sandy loam soils.

scholarly journals Chemical and Physical Analysis of a Petroleum Hydrocarbon Contamination on a Soil Sample to Determine Its Natural Degradation Feasibility

Inventions ◽  
2020 ◽  
Vol 5 (3) ◽  
pp. 43
Author(s):  
Karuna Arjoon ◽  
James G. Speight
Keyword(s):  
Contaminated Soils ◽  
Petroleum Hydrocarbon ◽  
Fossil Fuels ◽  
Chemical Properties ◽  
Cost Effective ◽  
Polluted Soil ◽  
Hydrocarbon Contamination ◽  
Contaminated Site ◽  
Physical Analysis ◽  
Oil Composition

Crude oil is the world’s leading fuel source and is the lifeblood of the industrialized nations as it is vital to produce many everyday essentials. This dependency on fossil fuels has resulted in serious environmental issues in recent times. Petroleum contaminated soils must be treated to ensure that human health and the environment remain protected. The restoration of petroleum-polluted soil is a complex project because once petroleum hydrocarbon enters the environment, the individual constituents will partition to various environmental compartments in accordance with their own physical–chemical properties; therefore, the composition and inherent biodegradability of the petroleum hydrocarbon pollutant determines the suitability of a remediation approach. The objective of this study was to assess the prospective of bioremediation as a feasible technique for practical application to the treatment of petroleum hydrocarbon-contaminated soils, by trending the changes in the properties of the petroleum due to biodegradation. Each polluted soil has particularities, thus, the bioremediation approach for each contaminated site is unique. Therefore, hydrocarbon-contaminated sites that have remained polluted for decades due to lack of proper decontamination treatments present in this part of the world would benefit from cost effective treatments. Most bioremediation case studies are usually based on hypothetical assumptions rather than technical or experimental data; providing data that show the capabilities of biodegradation of indigenous microbes on specific oil composition can lead to the creation of strategies to accelerate the biological breakdown of hydrocarbons in soil.

Response of plant growth to removal of surface soil of the rangelands of western Queensland.

1987 ◽  
Vol 9 (2) ◽  
pp. 74 ◽  
Author(s):  
AJ Pressland ◽  
DC Cowan
Keyword(s):  
Surface Soil ◽  
Ground Cover ◽  
Field Studies ◽  
Potential Effect ◽  
Plant Production ◽  
Grass Species ◽  
Pasture Grass ◽  
Subsurface Soil ◽  
Test Plants ◽  
Or History

Pot and field studies were conducted to determine the potential effect on plant production of soil erosion in western Queensland. Soil from both the Mitchell grass (Astrebla spp.) and mulga (Acacin aneura) woodlands were used, but the studies concentrated on the latter soils. Test plants (oats, sorghum and pasture grass species) were grown in soil taken from sequential 5 cm intervals from the surface to 20 cm down the profile of each of the selected soils. Plants growing in subsurface soil, irrespective of soil type or history, were less productive than those growing on surface soil. This was attributed in part to reduced soil fertility and a difference in soil pH. Buffel grass (Cenchrur ciliaris), a species which has some use as an improved pasture in these rangelands, would be seriously disadvantaged on eroded soils. It is concluded that erosion of surface soil on these landscapes should be minimized by conserving ground cover.

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