Bioaccessibility of As and Pb in orchard and urban soils amended with phosphate, Fe oxide and organic matter

Manufactured nanoparticles (MNPs) are increasingly released into the environment and thus research on their fate and behaviour in complex environmental samples is urgently needed. The fate of MNPs in the aquatic environment will mainly depend on the physico-chemical characteristics of the medium. The presence and concentration of natural organic matter (NOM) will play a significant role on the stability of MNPs by either decreasing or exacerbating the aggregation phenomenon. In this study, we firstly investigated the effect of NOM concentration on the aggregation behaviour of manufactured Fe-oxide nanoparticles. Then, the stability of the coated nanoparticles was assessed under relevant environmental conditions. Flow field-flow fractionation, an emerging method which is gaining popularity in the field of nanotechnology, has been employed and results have been compared to another size-measurement technique to provide increased confidence in the outcomes. Results showed enhanced stability when the nanoparticles are coated with NOM, which was due to electrosteric stabilisation. However, the presence of divalent cations, even at low concentration (i.e. less than 1 mM) was found to induce aggregation of NOM-coated nanoparticles via bridging mechanisms between NOM and Ca2+.

Download Full-text

Characterisation of Fe-oxide nanoparticles coated with humic acid and Suwannee River natural organic matter

The Science of The Total Environment ◽

10.1016/j.scitotenv.2013.04.083 ◽

2013 ◽

Vol 461-462 ◽

pp. 19-27 ◽

Cited By ~ 42

Author(s):

Laura Chekli ◽

Sherub Phuntsho ◽

Maitreyee Roy ◽

Ho Kyong Shon

Keyword(s):

Organic Matter ◽

Humic Acid ◽

Natural Organic Matter ◽

Oxide Nanoparticles ◽

Fe Oxide ◽

Suwannee River

Download Full-text

Metal contamination of urban soils in Cork, Ireland

10.5194/egusphere-egu21-15261 ◽

2021 ◽

Author(s):

Hannah Binner ◽

Timothy Sullivan ◽

Maria E. Mc Namara

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Metal Contamination ◽

Urban Soils ◽

Soil Samples ◽

Ex Situ ◽

City Centre ◽

Metal Concentrations ◽

Ph Values ◽

Background Levels

<p>Soil contamination is widespread across Europe. In particular, contamination of urban soils by metals is poorly characterised. This is a major environmental concern, especially given that urban recreational amenities may be located on former industrial sites and/or may possess ex situ soils derived from industrial areas. We surveyed soils from nine urban recreational sites (15 samples per site) in Cork city in order to assess the degree of metal contamination. The results show that Pb concentrations exceed national background levels in all soil samples from all sites by a mean of 600 % and at least 140 %. Mn, Fe and Zn are enriched above background levels in all soil samples from three (Mn and Fe) to five (Zn) of the sites and, at the remaining sites, show 7 &#8211; 14 localised hotspots. Similar hotspots characterise Cu, Rb and Sr, which each exceed background levels at eight or more sampling locations at four sites. Co, Ni, As and Sn concentrations exceed background levels in at least three hotspots at each of three to six sites. Overall, metal concentrations are highest in the sites closest to the city centre, reflecting diverse sources that potentially include traffic and current and historical domestic coal burning and industry. At each urban site, the element grouping Zn and Pb recurs in 50 to 80 % of locations and enrichment in the element grouping Mn, Fe, Cu, Zn and Pb recurs in approx. 50 % of locations; Ni and As recur in approx. 10 % of the locations. At three sites, elevated concentrations of Mn, Fe, Cu, Zn and Pb are associated with high LOI (Loss-on-ignition) values &#8211; a proxy for the amount of soil organic matter present &#8211; and near-neutral pH values. Conversely, low LOI and acidic pH values are associated with lower concentrations of these elements. This indicates that soil metal concentrations are influenced by the amount of organic matter present and by pH. &#160;Future analyses and experiments will further investigate links between soil organic matter and metal concentrations.</p>

Download Full-text

Copper availability as related to soil copper fractions in oxisols under liming

Scientia Agricola ◽

10.1590/s0103-90162003000100025 ◽

2003 ◽

Vol 60 (1) ◽

pp. 167-173 ◽

Cited By ~ 11

Author(s):

Clístenes Williams Araújo do Nascimento ◽

Renildes Lúcio Ferreira Fontes ◽

Adilson César Fortes Dias Melicio

Keyword(s):

Organic Matter ◽

Atomic Absorption Spectrophotometry ◽

Soil Samples ◽

Residual Fraction ◽

Soil Extracts ◽

Fe Oxide ◽

Cu Content ◽

Mn Oxide ◽

Copper Availability ◽

Organic Matter Fractions

The knowledge of the chemical forms of copper in soils and the relationships of these forms with soil copper availability are important for predicting the copper behavior in the soil-plant system. The present work studies the influence of liming on the available contents of copper as well as on the forms of copper fractions in six types of Oxisols. Soil samples, with and without liming, received copper at rates of 0.0, 20.0 and 40.0 mg dm-3 and remained incubated for 30 days. Then, available copper was extracted with Mehlich-1, Mehlich-3, DTPA and EDTA solutions, and analyzed by atomic absorption spectrophotometry. Additionally, soil samples were extracted in a sequential procedure to determine Cu in fractions of soil, as follows: exchangeable-Cu fraction, organic matter-Cu fraction, Mn oxide-Cu fraction, amorphous Fe oxide-Cu fraction, crystalline Fe oxide-Cu fraction, residual-Cu fraction, and the total Cu content in the soil. Soil samples to which Cu was added presented higher Cu retention in the organic matter fraction with a small percentage retained in the exchangeable-Cu fraction. Liming resulted in a decrease of Cu in the exchangeable and organic matter fractions and an increase in the Fe and Mn oxide fractions and in the residual fraction. Without liming, the organic matter fraction presented the highest contribution to Cu content found in the soil extracts obtained with all extractors, except EDTA. For treatments with liming, Cu contents in the organic matter fraction were better correlated to Cu contents in extracts obtained with DTPA and Mehlich-3.

Download Full-text

Organic matter of soils and technogenic surface formations of residential areas of the city of Perm

АгроЭкоИнфо ◽

10.51419/20215527 ◽

2021 ◽

Vol 5 (47) ◽

pp. 27-27

Author(s):

Natalia Moskvina ◽

Igor Shestakov ◽

Natalia Mitrakova

Keyword(s):

Organic Matter ◽

Urban Soils ◽

Left Bank ◽

Residential Areas ◽

Humus Formation ◽

Functional Zone ◽

Humus Type ◽

Reclaimed Soils ◽

The City ◽

Technogenic Surface Formations

On the territory of the left-bank part of Perm, the urban pedocomplexes (UPC) were distinguished as a combination of soil and technogenic surface formations on the same soil-forming rocks within a certain functional zone. Within the UPC, formed on eluvial-deluvial loams and clays in the zone of multi-storey buildings, the surface horizons of soils and TSF (technogenic surface formations) were studied. A change in the zonal trend of humus formation in reclaimed soils was observed as an increase in the content of organic matter, as well as in a change in the type of humus to the humate side. The conservation of zonal features of humus formation in non-purposefully recultivated urban soils and TSF was noted. It manifests in a low or medium content of organic carbon, the formation of a humate-fulvate type of humus. Keywords: URBAN ECOLOGY, URBAN SOILS, URBAN PEDOCOMPLEX, HUMUS, HUMUS TYPE, SOIL PROPERTIES

Download Full-text

Organic matter of urban soils: A review

Eurasian Soil Science ◽

10.1134/s1064229315080116 ◽

2015 ◽

Vol 48 (8) ◽

pp. 802-811 ◽

Cited By ~ 14

Author(s):

Yu. N. Vodyanitskii

Keyword(s):

Organic Matter ◽

Urban Soils

Download Full-text

Carbon and Metal(loid)s in Parkland and Road Verge Surface Soils in the City of Liverpool, UK

Agronomy ◽

10.3390/agronomy10030335 ◽

2020 ◽

Vol 10 (3) ◽

pp. 335 ◽

Cited By ~ 1

Author(s):

Luke Beesley ◽

Eduardo Moreno-Jiménez ◽

Phil Jenn ◽

Nicholas W. Lepp

Keyword(s):

Organic Matter ◽

Organic Carbon ◽

Urban Soils ◽

Public Spaces ◽

Soil Survey ◽

Water Soluble ◽

Surface Soils ◽

Road Verge ◽

C Storage ◽

The City

Urban soils are at the interface between land and people and provide a wide variety of important ecosystem services to highly populous areas. The aims of this soil survey were (1) to measure the bulk density, carbon (C) storage and pH of surface soils (0–15 cm depth) from public spaces (parks and road verges) in the city of Liverpool, UK, and (2) to determine the likely impact of these master variables on heavy metal concentrations (As, Cd, Cu, Pb and Zn). The bulk densities and organic matter contents varied considerably in the predominantly sandy textured soils within the city boundary, resulting in diverse C densities from 1–10 kg C m2. Organic carbon formed the majority of the labile, water-soluble and extractable C pool in these soils, a fact not easily elucidated from their organic matter or C content alone. The copper and lead concentrations in the sampled soils were correlated with organic matter and organic carbon in water-extracts. Cadmium and zinc appeared to be dependent only on soil pH, whilst arsenic was related positively to organic matter, but negatively to pH. Interrelationships, and hence synonymous distributions, of all metal(loid)s existed, but were strongest between Cu and As, and Cu and Pb. These results suggest that the diverse bulk densities, and hence carbon storage, of the urban soils surveyed influenced the dispersal of metals and arsenic.

Download Full-text

Soil organic matter in urban soils: Estimation of elemental carbon by thermal oxidation and characterization of organic matter by solid-state 13C nuclear magnetic resonance (NMR) spectroscopy

Geoderma ◽

10.1016/j.geoderma.2005.02.004 ◽

2006 ◽

Vol 130 (3-4) ◽

pp. 312-323 ◽

Cited By ~ 50

Author(s):

K. Lorenz ◽

C.M. Preston ◽

E. Kandeler

Keyword(s):

Nuclear Magnetic Resonance ◽

Organic Matter ◽

Solid State ◽

Nmr Spectroscopy ◽

Soil Organic Matter ◽

Magnetic Resonance ◽

Urban Soils ◽

Elemental Carbon ◽

13C Nuclear Magnetic Resonance

Download Full-text

Interactive effects of iron oxides and organic matter on charge properties of red soils in Thailand

Soil Research ◽

10.1071/sr13021 ◽

2013 ◽

Vol 51 (3) ◽

pp. 222 ◽

Cited By ~ 8

Author(s):

D. Ketrot ◽

A. Suddhiprakarn ◽

I. Kheoruenromne ◽

B. Singh

Keyword(s):

Organic Matter ◽

Humic Acid ◽

Clay Fraction ◽

Interactive Effects ◽

Soil Conditions ◽

Oxide Surfaces ◽

Fe Oxide ◽

Fe Oxides ◽

Red Soils ◽

Variable Surface

Iron (Fe) oxides and organic matter (OM) play important roles in maintaining the fertility of highly weathered soils. The main objective of this study was to investigate the interactive effects of variable surface charge minerals, particularly Fe oxide minerals, and OM on the charge properties of red soils from Thailand. We also evaluated the effect of the 5 m NaOH procedure, used to concentrate Fe oxides from soils, on the charge characteristics of Fe oxide concentrates. Fourteen clay fractions (untreated and OM-free clay fractions), and Fe oxide concentrates of these clays, were used in the study. Cation exchange capacity (CEC) and electrophoretic mobility (EM) were measured for the soil clays, artificial mixtures, and goethite adsorbed with humic acid (HA) and phosphate (P). Kaolinite and Fe oxides (predominantly a mixture of hematite and goethite) were the main minerals in the clay fraction. Results indicated that OM or metal–OM complexes may have blocked or neutralised negatively charged sites on clay minerals. After OM removal these sites became accessible, inducing an increase in CEC and shifting the EM values towards more negative values and the isoelectric point (IEP) towards lower pH for many samples. The CEC values of Fe oxide concentrates prepared by 5 m NaOH treatment were overestimated and their EM and IEP shifted towards more negative values. It is possible that the amorphous phase from clay dissolution was still present in the Fe oxide concentrates, or the adsorption of silicate ions modified the surfaces of Fe oxides concentrates. Humic acid and P adsorbed on Fe oxide surfaces caused the IEP to shift to lower values. In natural soil conditions, a variety of anions can be adsorbed on Fe oxide surfaces, which might lead to higher values of negative charge and lower IEP than observed for pure synthetic minerals.

Download Full-text

ORGANIC SUBSTANCE IN THE SOILS OF TRANSPORTATION AND RECREATION ZONES OF YAKUTSK

10.31453/kdu.ru.978-5-7913-1195-5-2021-24-31 ◽

2021 ◽

Author(s):

Diyana Vasilievna Obutova ◽

◽

Marina Vladimirovna Schelchkova ◽

Keyword(s):

Organic Matter ◽

Organic Substance ◽

Urban Soils ◽

Green Spaces ◽

Floodplain Meadow

The content of organic matter in the Yakutsk city soils of the recreational zones (squares, park of culture and rest, floodplain meadow) and transport zones (lawns along major transport routes) was studied. It is shown that the urban soils of Yakutsk under green spaces are characterized by low potential fertility. They are poor in humus and are moderately supplied with alkaline hydrolysable nitrogen.

Download Full-text