Copper Partitioning Among Mineral and Organic Fractions in Biosolids

2006 ◽  
Vol 3 (1) ◽  
pp. 48 ◽  
Author(s):  
I. W. Oliver ◽  
G. Merrington ◽  
M. J. McLaughlin

Environmental Context.Only a portion of the total amount of heavy metals present in sewage biosolids is accessible to organisms, including plants, and therefore only that portion presents any possible toxicity threat. However, metals such as copper, which are commonly associated to a large degree with the organic fraction, may become more accessible over time as organic components degrade. Determining the extent of partitioning of Cu between the organic and inorganic fractions may provide an indication of any long-term risks associated with utilisation of biosolids in agriculture. Abstract.Metal partitioning between organic and mineral fractions in biosolids may provide an indication of the long-term risks associated with land application of the material. For example, metals found to partition into the organic phase may pose a potential threat when the organic matter is decomposed, whereas metals bound in the mineral fraction would be expected to remain stable over time (given no changes in other environmental conditions) owing to the stability of mineral components. Therefore the question of which components bind copper in biosolids, and whether the sorption capacity is maintained over time, was addressed in the present study. Biosolids incubated for 21 months and non-incubated controls were examined. The solid–solution distribution coefficient (Kd) for Cu was measured in whole biosolids and in biosolid organic and mineral fractions via batch experiments employing the radioactive isotope 64Cu. The mineral fraction was isolated by NaOCl oxidation, whereas the organic fraction was isolated using HF. Results found the relative importance of mineral and organic fractions to Cu sorption varies between biosolids, and in some cases can vary over time. Reduction in sorption capacity caused by losses of organic matter in some biosolids suggests the possibility of increased availability of biosolid metals over time.

1987 ◽  
Vol 65 (12) ◽  
pp. 2601-2606 ◽  
Author(s):  
J. Maheswaran ◽  
P. M. Attiwill

The losses of organic matter, elements and organic fractions during the decomposition of Eucalyptus microcarpa Maiden leaf litter were measured in litterbags. The concentrations of nitrogen and phosphorus in litter increased for most of the decomposition period. At the end of 15 months the amounts of elements lost were in the order K > Na > Mg > P > N >Ca. A simple method to determine the different organic fractions according to the degree of decomposability and using a small quantity of litter (0.1 – 0.5 g) was developed. The mass loss during the initial 3 months was most closely related to the amount of light organic fraction in the litter, while during the final 12 months the mass loss was most closely related to the harder organic fractions in the litter.


2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Qin Lu ◽  
Zhenli L. He ◽  
Peter J. Stoffella

Land application of biosolids has proven a cost-effective method of waste disposal by beneficially recycling organic matter and nutrients and improving soil quality; however, it may also pose potential threat to the environment and human health. The purpose of this paper is to provide information on recent research progresses and regulation efforts regarding land application of biosolids, including forms and types and nutrient values of biosolids, environmental and health concerns, and related best management practices (BMPs) of biosolids application, with emphasis on its land application in agriculture. More research and regulations are expected to minimize potential risks of biosolids land application, especially its long-term impacts.


Forests ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 468
Author(s):  
Philip M. Crim ◽  
Jonathan R. Cumming

Anthropogenic emissions have impacted terrestrial forest ecosystem processes in North America since the industrial revolution. With the passage of the Clean Air Act in 1970 in the United States, atmospheric inputs of nitrogen (N) and sulfur (S) into forests in the Appalachian Mountains have declined, which have, potentially, mitigated their effects on processes such as decomposition and nutrient cycling. Activities of microbial extracellular soil enzymes (ESEs) mediate many rate-limiting nutrient transformations in forest soils and play important roles in the decomposition of complex organic compounds. Soils in high-elevation red spruce forests are characterized by low pH and high carbon (C):N ratios and, having historically received extremely high levels of N deposition, may exhibit legacy impacts of deposition on nutrient availability and decomposition. We utilized four sites along a modeled gradient of N deposition in central Appalachia to assess contemporary ESEs in bulk soil under Acer rubrum L., Betula alleghaniensis Britt., and Picea rubens Sarg. in May, June, and July 2016. Increasing N deposition led to increases in organic fraction C and N and decreases in phosphorus (P). Sites receiving higher N also exhibited greater mineral fraction C, N, and P. ESEs were highest in organic fractions with acid phosphatases (AP) exhibiting the highest activity. There was little influence of N deposition on organic fraction ESEs, but strong evidence for a positive relationship between N deposition and activities of AP, β-glucosidases (BG), and chitinase (NAG) in mineral fractions. Species effects on ESEs were present with high AP in organic fractions under spruce and high mineral fraction fungal laccase (LAC) under birch. The sampling season demonstrated little effect on ESEs. ESEs were more strongly influenced by plot-level factors, such as tree species diversity and abundance of ectomycorrhizal (ECM) tree species, than temporal or soil factors or nutrient status related to modeled cumulative N deposition across these sites. Decreases in AP, BG, and NAG activities with greater abundance of broadleaf deciduous species and increases in activities with ECM host abundance indicate that microbial communities driven by these plant functional groups are responsible for the differences in ESEs observed in these high-elevation mixed red spruce stands.


1963 ◽  
Vol 43 (2) ◽  
pp. 275-286 ◽  
Author(s):  
C. D. Sawyer ◽  
S. Pawluk

Humic acids, polysaccharides, and polyuronides were extracted from samples representative of the organic and mineral A horizons of two Dark Grey Wooded soils. These organic fractions were characterized in order to determine the alterations, if any, which may be evident in some of the organic constituents present at varying depths in the organic and mineral A horizons as a result of progressive podzolic degradation.Humic acid content in the organic fraction was found to decrease with depth in the mineral A horizon. Methoxyl content of the purified humic acids averaged 0.26 me./g. and decreased with depth while the total acidity (phenolic and carboxyl acidity) averaged 7.6 me./g. and increased with depth. Nitrogen content of the purified humic acids averaged 2.6 per cent and was relatively constant throughout the organic and mineral A horizons. The humic acid content of the undecomposed and semi-decomposed organic debris was found to be only slightly lower than that of the Ah horizon. This was probably at least partially due to hydrolyses of organic matter during the harsh extraction of humic acids with warm 1.0 N NaOH.Total polysaccharide and polyuronide content of these soils decreased rapidly with depth; however, this decrease paralleled the decrease in total organic carbon content.


Water Policy ◽  
2005 ◽  
Vol 7 (5) ◽  
pp. 469-483
Author(s):  
Tishya Chatterjee

In conditions of severe water-pollution and dormant community acceptance of accumulating environmental damage, the regulator's role goes beyond pollution prevention and more towards remediation and solutions based on the community's long-term expectations of economic benefits from clean water. This paper suggests a method to enable these benefits to become perceptible progressively, through participatory clean-up operations, supported by staggered pollution charges. It analyses the relevant literature on pollution prevention and applies a cost-based “willingness to pay” model, using primary basin-level data of total marginal costs. It develops a replicable demand-side approach imposing charge-standard targets over time in urban-industrial basins of developing countries.


2017 ◽  
Vol 2017 (1) ◽  
pp. 1056-1064
Author(s):  
Jake Finlinson ◽  
Dave Ruud ◽  
Andy Bary ◽  
Maile Lono-Batura

Author(s):  
Halil Kaya ◽  
Gaurango Banerjee

The paper examines the Sarbanes-Oxley (2002) Acts immediate impact on board composition and characteristics as well as possible reversals in its impact over time. Effects on directors age and tenure are analyzed over the 2001-06 sample period. Female participation in corporate boards is also studied in the pre-SOX and post-SOX periods. The dual roles of directors in being a member of the board as well as serving as either CEO, CFO, Chairman, Co-Chair, Founder, or Lead Director of their respective companies is also examined. We observe a short-term impact of SOX on board compositions due to changes seen in board characteristics between 2001 (pre-SOX), and 2003-05 short-term period (post-SOX). Also, we observe a reversal of board characteristics in 2006 to pre-SOX levels implying that the effects of SOX on board composition were short-lived, and needs to be monitored over time to ensure adherence to corporate accountability guidelines over the long-term.


2019 ◽  
Vol 135 ◽  
pp. 396-406 ◽  
Author(s):  
Bryony E.A. Dignam ◽  
Maureen O'Callaghan ◽  
Leo M. Condron ◽  
Jos M. Raaijmakers ◽  
George A. Kowalchuk ◽  
...  

2021 ◽  
pp. 194016122110252
Author(s):  
Sebastián Valenzuela ◽  
Daniel Halpern ◽  
Felipe Araneda

Despite widespread concern, research on the consequences of misinformation on people's attitudes is surprisingly scant. To fill in this gap, the current study examines the long-term relationship between misinformation and trust in the news media. Based on the reinforcing spirals model, we analyzed data from a three-wave panel survey collected in Chile between 2017 and 2019. We found a weak, over-time relationship between misinformation and media skepticism. Specifically, initial beliefs on factually dubious information were negatively correlated with subsequent levels of trust in the news media. Lower trust in the media, in turn, was related over time to higher levels of misinformation. However, we found no evidence of a reverse, parallel process where media trust shielded users against misinformation, further reinforcing trust in the news media. The lack of evidence of a downward spiral suggests that the corrosive effects of misinformation on attitudes toward the news media are less serious than originally suggested. We close with a discussion of directions for future research.


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