scholarly journals Substantial Decrease in Contaminant Concentrations in the Sediments of the Venice (Italy) Canal Network in the Last Two Decades—Implications for Sediment Management

Water ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1965 ◽  
Author(s):  
Roberto Zonta ◽  
Daniele Cassin ◽  
Roberto Pini ◽  
Janusz Dominik
Keyword(s):  
Heavy Metal ◽  
Sediment Cores ◽  
Sediment Management ◽  
Antifouling Paint ◽  
Substantial Decrease ◽  
Dredged Sediments ◽  
Network Maintenance ◽  
Canal Network ◽  
The Cost ◽  
Dredging Operation

The Venice canal network requires periodic intervention to remove sediments that progressively accumulate. The most recent dredging operation was carried out in the second half of the 1990s and early 2000s. These sediments had accumulated over a period of more than 30 years and were highly contaminated with Cd, Cu, Hg, Pb, Zn and PAHs. Sediments deposited after the dredging work were investigated in 2005, 2009, 2014 and 2017 by analysing sediment cores collected from three sites in the canal network. Arsenic, heavy metal and PAH concentrations were observed to be much lower than past values, although Cu, Hg and PAH levels were still relatively high. The high Cu concentrations (mean 161 mg kg−1) are partly due to the widespread use of Cu-based antifouling paint. Current Italian regulations forbid the disposal of dredged sediments with these concentrations inside the lagoon, thereby increasing the cost of canal network maintenance.

scholarly journals Synthesis of Zeolite from Fly Ash and Removal of Heavy Metal Ions from Newly Synthesized Zeolite

2010 ◽  
Vol 7 (4) ◽  
pp. 1200-1205 ◽  
Author(s):  
Parag Solanki ◽  
Vikal Gupta ◽  
Ruchi Kulshrestha
Keyword(s):  
Heavy Metal ◽  
Fly Ash ◽  
Metal Ions ◽  
Heavy Metal Ions ◽  
Coal Fly Ash ◽  
Proximate Analysis ◽  
13X Zeolite ◽  
Alkali Fusion ◽  
Type Zeolite ◽  
The Cost

Coal fly ash was used to synthesize X-type zeolite by alkali fusion followed by hydrothermal treatment. Characteristics of the various Fly ash samples were carried out. Coal proximate analysis was done. Batch experiment was carried out for the adsorption of some heavy metal ions on to synthesized Zeolite. The cost of synthesized zeolite was estimated to be almost one-fifth of that of commercial 13X zeolite available in the market.

Enhanced Heavy Metal Phytoextraction from Marine Dredged Sediments Comparing Conventional Chelating Agents (Citric Acid and EDTA) with Humic Substances

2008 ◽  
Vol 193 (1-4) ◽  
pp. 323-333 ◽  
Author(s):  
Veronica Bianchi ◽  
Grazia Masciandaro ◽  
David Giraldi ◽  
Brunello Ceccanti ◽  
Renato Iannelli
Keyword(s):  
Heavy Metal ◽  
Citric Acid ◽  
Humic Substances ◽  
Chelating Agents ◽  
Dredged Sediments

Heavy metal distribution in sediment cores from Western Ross Sea (Antartica)

1997 ◽  
Vol 99 (1-4) ◽  
pp. 697-704 ◽  
Author(s):  
M. Ravanelli ◽  
O. Tubertini ◽  
S. Valcher ◽  
W. Martinotti
Keyword(s):  
Heavy Metal ◽  
Ross Sea ◽  
Sediment Cores ◽  
Metal Distribution ◽  
Heavy Metal Distribution ◽  
Western Ross Sea

Assessment of potential risks associated with heavy metal contamination in sediment in Aobaopao Lake, China, determined from sediment cores

Ecotoxicology ◽  
2014 ◽  
Vol 23 (4) ◽  
pp. 527-537 ◽  
Author(s):  
Haifeng Xiao ◽  
Shuying Zang ◽  
Ying Guan ◽  
Shaojun Liu ◽  
Yan Gao ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Metal Contamination ◽  
Heavy Metal Contamination ◽  
Sediment Cores ◽  
Potential Risks

The use of flux-corer experiments in the determination of heavy metal re-distribution in and of potential leaching from the sediments

1998 ◽  
Vol 37 (6-7) ◽  
pp. 283-290 ◽  
Author(s):  
R. Van Ryssen ◽  
M. Alam ◽  
L. Goeyens ◽  
W. Baeyens
Keyword(s):  
Heavy Metal ◽  
Water Policy ◽  
Sediment Cores ◽  
Metal Mobility ◽  
Overlying Water ◽  
Heavy Metal Mobility ◽  
Zn And Cu In ◽  
Concentration Changes ◽  
The Impact

Metal dynamics between sediments, interstitial water and overlying water are particularly complex. The movement of metals, their availability, and possible toxicity are influenced by various chemical and physical reactions and factors such as oxygen/redox gradients, pH, grain size, etc. To study the impact of oxygen on the release from and the re-distribution of Cd, Pb, Zn and Cu in sediments, flux-corer experiments have been optimised and performed. The flux experiment was carried out using 3 identical sediment cores. The first (control) sediment core was completely characterised before, the two other cores after the experiment. Pore water extractions and sequential extractions were performed on 2 cm depth intervals throughout the 20 cm long sediment cores. In the flux experiment, the sediment cores were exposed to a small volume of overlying water, which was continuously renewed. The change of trace metal mobility was assessed by following concentration-changes in the outflow. It has been found by the use of the flux-corer experiment, that the Cd, Pb, Zn and Cu concentrations in the outflow are at least 3-6 times higher during oxic conditions. Flux-corer experiments can be useful tools to facilitate the study of the change of heavy metal mobility and distribution in the sediment induced by the change in surface water policy.

scholarly journals Assessment of Nutrient and Heavy Metal Pollution in Channel Dredged Sediments in the middle and lower reaches of the Yangtze basin

2020 ◽  
Vol 145 ◽  
pp. 02037
Author(s):  
Hongxia Xiong ◽  
Shitao Peng ◽  
Wei Huang ◽  
Xinlei Liu ◽  
Xianbin Liu
Keyword(s):  
Heavy Metal ◽  
Yangtze River ◽  
Yangtze River Basin ◽  
Technical Problem ◽  
Available N ◽  
Dredged Sediments ◽  
Dredged Materials ◽  
Yangtze Basin ◽  
The Yangtze River Basin ◽  
Important Direction

There was a large amount of dredged materials produced stably in the Yangtze waterway each year. How to dispose these dredged materials was a major technical problem in the field of port and waterway engineering. The dredged materials were valuable resource, and the utilization of dredged materials in landscape can be an important direction in the future. To analyze the feasibility of dredging for landscaping, the waterway dredged sediments from middle and lower reaches of the Yangtze River basin, such as Dongting Lake, Chenglingji section, Zhenjiang section, Nantong section and Taihu Lake were collected, and the nutrient characteristics, heavy metal content and pollution degree were analyzed. The results showed that the pH, moisture content, petroleum hydrocarbons, organic matter and available P in Yangtze River waterway dredging sediments were 7.28~7.74, 3.75~28.27%, 14.21~121.84 ppm, 1.88~5.29% and 16.96~65.38 ppm respectively, which were moderate pollution and suitable for plants growth. The content of available N and available K content were 67.12~87.97 ppm and 2.78~20.11 ppm, which were too low to meet the needs of plant growth. Extra sources of nitrogen and potassium should be added into the sediments when reused. Dredged sediments were contaminated by heavy metals Cu, Pb and Zn, the evaluation results showed that their enrichment effect was not obvious, which won’t affect the sediment utilization. Dredged sediments were widely contaminated by Cd (0.05~2.68 mg/kg), and there was a certain enrichment effect, so some Cd hyperaccumulators should be planted to remediate Cd in dredged sediments.

scholarly journals Use of phytoremediation and biochar to remediate heavy metal polluted soils: a review

Solid Earth ◽  
2014 ◽  
Vol 5 (1) ◽  
pp. 65-75 ◽  
Author(s):  
J. Paz-Ferreiro ◽  
H. Lu ◽  
S. Fu ◽  
A. Méndez ◽  
G. Gascó
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Contaminated Soils ◽  
State Of The Art ◽  
Anthropogenic Activities ◽  
Sustainable Use ◽  
Research Needs ◽  
Polluted Soils ◽  
Environmental Technologies ◽  
The Cost

Abstract. Anthropogenic activities are resulting in an increase of the use and extraction of heavy metals. Heavy metals cannot be degraded and hence accumulate in the environment, having the potential to contaminate the food chain. This pollution threatens soil quality, plant survival and human health. The remediation of heavy metals deserves attention, but it is impaired by the cost of these processes. Phytoremediation and biochar are two sound environmental technologies which could be at the forefront to mitigate soil pollution. This review provides an overview of the state of the art of the scientific research on phytoremediation and biochar application to remediate heavy-metal-contaminated soils. Research to date has attempted only in a limited number of occasions to combine both techniques, however we discuss the potential advantages of combining both, and the potential mechanisms involved in the interaction between phytoremediators and biochar. We identified specific research needs to ensure a sustainable use of phytoremediation and biochar as remediation tools.

scholarly journals Prediction Approach of Critical Node Based on Multiple Attribute Decision Making for Opportunistic Sensor Networks

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Qifan Chen ◽  
Linlan Liu ◽  
Zhiyong Yang ◽  
Kai Guo
Keyword(s):  
Decision Making ◽  
Network Performance ◽  
Multiple Attribute Decision Making ◽  
Critical Node ◽  
Cut Vertex ◽  
Critical Nodes ◽  
Multiple Attribute ◽  
Network Maintenance ◽  
The Cost ◽  
Prediction Approach

Predicting critical nodes of Opportunistic Sensor Network (OSN) can help us not only to improve network performance but also to decrease the cost in network maintenance. However, existing ways of predicting critical nodes in static network are not suitable for OSN. In this paper, the conceptions of critical nodes, region contribution, and cut-vertex in multiregion OSN are defined. We propose an approach to predict critical node for OSN, which is based on multiple attribute decision making (MADM). It takes RC to present the dependence of regions on Ferry nodes. TOPSIS algorithm is employed to find out Ferry node with maximum comprehensive contribution, which is a critical node. The experimental results show that, in different scenarios, this approach can predict the critical nodes of OSN better.

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