scholarly journals Predicting Event-Based Sediment and Heavy Metal Loads in Untreated Urban Runoff from Impermeable Surfaces

Water ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 969
Author(s):  
Frances J. Charters ◽  
Thomas A. Cochrane ◽  
Aisling D. O’Sullivan

Understanding the amount of pollutants contributed by impermeable urban surfaces during rain events is necessary for developing effective stormwater management. A process-based pollutant load model, named Modelled Estimates of Discharges for Urban Stormwater Assessments (MEDUSA), was further developed (MEDUSA2.0; Christchurch, New Zealand) to include simulations of dissolved metal loadings and improve total suspended solids (TSS) loading estimations. The model uses antecedent dry days, rainfall pH, average event intensity and duration to predict sediment and heavy metal loads generated by individual surfaces. The MEDUSA2.0 improvements provided a moderate to strong degree of fit to observed sediment, copper, and zinc loads for each modelled road and roof surface type. The individual surface-scale modelling performed by MEDUSA2.0 allows for identification of specific source areas of high pollution for targeted surface management within urban catchments.

Author(s):  
Andrea Vannini ◽  
Luca Paoli ◽  
Riccardo Fedeli ◽  
Sharon Kwambai Kangogo ◽  
Massimo Guarnieri ◽  
...  

AbstractIn this study, the release of Cu2+ and Zn2+ was investigated and modeled in the epiphytic lichen Evernia prunastri. Samples were incubated with solutions containing these metals at ecologically relevant concentrations (10 and 100 μM) and then transplanted to a remote area and retrieved after 1, 2, 3, 6, 12, and 18 months. The results showed that, after 12 months, all samples faced similar metal reductions of ca. 80–85%, but after this period, all the involved processes seem to be no longer capable of generating further reductions. These results suggest that the lichen E. prunastri can provide information about environmental improvements after exposure to high or very high pollution levels in a relatively short period of time.


Author(s):  
Farnaz Seyedvakili ◽  
Mohammad Samipoorgiri

A coupled adsorption–desorption thermo-kinetic model is developed incorporating both adsorption and desorption reactions. A local pseudo-equilibrium condition at the interface of adsorbent and adsorbate bulk phases was used as isotherm equation which can even be applied for multi-pollutants scenarios. The developed model is then validated using collected experimental data of heavy metal ions (Pb, Cu, Cd, Zn, and Ni). Comparisons were made for a number of isotherm and kinetic models to examine the performance of the proposed model. The developed model revealed desirable accuracy and superiority over other models in predicting the adsorption behavior and can be used for other systems of concern. The model correlates the adsorption kinetic with an [Formula: see text] value of 0.9391 and desorption kinetic with an [Formula: see text] value of 0.9383. By application of the proposed model to any available adsorption datasets, the individual characteristics of adsorption and desorption can be determined.


2018 ◽  
Vol 70 ◽  
pp. 11-23 ◽  
Author(s):  
Oleg Marenkov ◽  
Mykola V. Prychepa ◽  
Julia Kovalchuk

In the experiment with marbled crayfishProcambarusvirginalis(Lyko, 2017), chronic effects of various concentrations of heavy metal ions on the physiological state and enzyme activity were investigated. The obtained results showed that among the investigated heavy metals nickel ions influenced the weight indexes and mortality of crustaceans the most negatively. According to the results of the research, significant changes were noted in the individual biochemical parameters of marbled crayfish under the influence of manganese, lead and nickel ions. The most significant changes in the activity of lactate dehydrogenase were detected in muscle tissues affected by manganese and nickel ions. A significant decrease in the activity of succinate dehydrogenase in muscle of marbled crayfish was determined after the action of heavy metal ions. Investigation of changes in the activity of alkaline phosphatase under the influence of the ions of manganese, lead and nickel has its own characteristics, which indicates certain violations in the tissues of cell membranes. Changes in the activity of enzymes were also reflected in the overall protein content. Changes in these parameters may indicate a rapid biochemical response of crustaceans to the toxic effects of heavy metals.


2021 ◽  
Vol 59 (2) ◽  
pp. 9-19
Author(s):  
Adam Lowenstein

Abstract This essay analyzes how George A. Romero, in his underrated psychological vampire film Martin, translates individual trauma (slow, process-based, unrecognized) into collective trauma (sudden, event-based, recognized) through a vocabulary of horror. The language of trauma spoken by Martin is not the one we expect from the horror film, with its traditional investments in fantastic spectacle. Instead, it is a language that combines horror’s fantastic vocabulary and documentary’s realist vocabulary in ways that undermine our attempts to distinguish between the two modes. Romero’s vision urges us to see catastrophe where we are accustomed to seeing only the mundane, and collective trauma where we routinely see only individual trauma. In Martin’s version of horror, the economic decline of Braddock, Pennsylvania, is paired with trauma connected to the Vietnam War and immigration. The film moves between these coordinates to revisualize the distinctions that divide the fantastic from the real as well as the individual from the collective.


1981 ◽  
Vol 8 (3) ◽  
pp. 665 ◽  
Author(s):  
DM Howarth ◽  
AJ Hulbert ◽  
D Horning

Tissues taken from crested terns were analysed for cadmium, lead, copper, chromium, manganese, zinc and iron. The birds were taken from a breeding colony in a non-industrialized region (North Solitary I., NNE. of Coffs Harbour, N.S.W.) and from one near an industrialized region (Big I., Port Kembla, N.S.W.). The birds from the industrialized region did not show any consistent evidence of significant heavy metal contamination when compared to those of the non-industrialized region. The individual tissues were also compared to assess the distribution of the various metals, and the relative degree to which each tissue accumulates the metals. Some accumulation of chromium, copper, manganese, lead and, to a lesser degree, cadmium and zinc was found in the salt glands. The kidneys had a relatively large cadmium content.


2013 ◽  
Vol 726-731 ◽  
pp. 296-300
Author(s):  
Zhi Gang Chen ◽  
An Ping Wei ◽  
Xiao Hong Zhou

The purpose of this paper is to study the speciation and contents of two types of heavy metals (Cd and Hg) in the sediments in Power Bridge (D1) and Nanshui Bridge (N2) in the middle part of the Ancient Canal in Zhenjiang. The relationship between the speciation of these heavy metals and their environmental factors were described. Morerover, the ecological hazard and trace to the source of these two types of heavy metals was also determined preliminarily. The results showed that (1) the main heavy metal contamination in the sediments of Power Bridge and Nanshui Bridge is Cd, and the average value is 20 mg/Kg, 17 mg/Kg, respectively, which were higher than environmental background value;(2) The peak value of Hg and Cd were near equilibrium in the 0.1-0.2m depth of Sediments; (3) Calculate the individual potential ecological risk index in the sediments of heavy metal element of two sample points both quantity of contents are Cd>Hg. And visible ecological threat of heavy metals were from Cd. After removing the Cd value, the RI value showed that ecological harm index basically below mild ecological harm degree.


2016 ◽  
Vol 371 (1708) ◽  
pp. 20160005 ◽  
Author(s):  
Satoshi Umeda ◽  
Saiko Tochizawa ◽  
Midori Shibata ◽  
Yuri Terasawa

Previous studies on prospective memory (PM), defined as memory for future intentions, suggest that psychological stress enhances successful PM retrieval. However, the mechanisms underlying this notion remain poorly understood. We hypothesized that PM retrieval is achieved through interaction with autonomic nervous activity, which is mediated by the individual accuracy of interoceptive awareness, as measured by the heartbeat detection task. In this study, the relationship between cardiac reactivity and retrieval of delayed intentions was evaluated using the event-based PM task. Participants were required to detect PM target letters while engaged in an ongoing 2-back working memory task. The results demonstrated that individuals with higher PM task performance had a greater increase in heart rate on PM target presentation. Also, higher interoceptive perceivers showed better PM task performance. This pattern was not observed for working memory task performance. These findings suggest that cardiac afferent signals enhance PM retrieval, which is mediated by individual levels of interoceptive accuracy. This article is part of the themed issue ‘Interoception beyond homeostasis: affect, cognition and mental health’.


2019 ◽  
Vol 3 (3) ◽  
pp. 11
Author(s):  
Eda ERMAĞAN ÇAĞLAR ◽  
Neşe KOCABAŞOĞLU

The aim of the study was to determine the influence of authority on the susceptibility of child witnesses and the reliability of their testimonies. This study, consisting of experimental and control groups, included 20 girls and 20 boys, totalling 40 children. It took place in two phases; an initial phase (“eyewitness”, “post-event interview”) and, one week later, a final phase (“recall”). In the individual interviews held with the children, a questionnaire consisting of a free narrative question and 18 open-ended questions was used. The free narrative question asked the children to specify the details they remembered about the animated film. The open-ended questions focused on the events and characters in the film. However, 12 of the open-ended questions could be answered correctly since they were about characters and situations in the film that the children had watched, while six of the questions were trick questions that were about characters and situations that were not shown in the film. For data analysis, both quantitative and qualitative methods were used to reach the deeper level of perception and memories that children shared about the film. In conclusion, after analysis, it was found that even when the interview takes place immediately after the event, children are significantly affected by the misinformation given by an adult and their knowledge on the event in question is shaped according to this misinformation. It was observed that children create "a new event" based on the information they receive from an adult. Keywords: Child, Eyewitness testimony, Reliability, Suggestibility, Suggestive interview, Memory


Author(s):  
Chuanyu Wu ◽  
Meiling Liu ◽  
Xiangnan Liu ◽  
Tiejun Wang ◽  
Lingyue Wang

In natural farmland ecosystems, cadmium (Cd) pollution in rice has attracted increasing attention because of its high toxicity, relative mobility, and high water solubility. This study aims to develop a spectral index for detecting Cd stress in rice on a regional scale. Three experimental sites are selected in Zhuzhou City, Hunan Province. The hyperspectral data, chlorophyll (Chl) content, leaf area index, average leaf angle, Cd concentration in soil, and Sentinel-2A images from 2017 and 2018 are collected. A new spectral index sensitive to Cd stress in rice is established based on the global sensitivity analysis of the radiative transfer model PROSPECT + SAIL (commonly called PROSAIL) model with the auxiliary of the field-measured data. The heavy metal Cd stress-sensitive spectral index (HCSI) is devised as an indicator of the degree of Cd stress in rice. Results indicate that (1) the HCSI developed based on Chl is a good indicator of rice damage caused by Cd stress, that is, low values of HCSI occur in rice subject to relatively high pollution; (2) compared with common spectral indices, such as red-edge position and red-edge Chl index, HCSI is more sensitive to Chl content with higher Pearson correlation coefficients with respect to Chl content, ranging from 0.85 to 0.95; (3) HCSI is successfully applied in Sentinel-2A images from the two different years of monitoring rice Cd stress on a regional scale. Cd stress levels in rice stabilized, and the largest area percentage of each pollution levels of Cd decreased in the following order: No pollution (i.e., 40%), low pollution (i.e., 35%), and high pollution (i.e., 25%). This study indicates that a combination of simulation data from the PROSAIL model and measured data appears to be a promising method for establishing a sensitivity spectral index to heavy metal stress, which can accurately detect regional Cd stress in crops.


2021 ◽  
pp. 074823372110073
Author(s):  
Ying-Jian Sun ◽  
Qing-Juan Cao ◽  
Ming-Yuan Xu ◽  
Lin Yang ◽  
Yi-Jun Wu

The organochlorine insecticide dichlorodiphenyltrichloroethane (DDT) and heavy metal cadmium (Cd) are widespread environmental pollutants. They are persistent in the environment and can accumulate in organisms. Although the individual toxicity of DDT and Cd has been well documented, their combined toxicity is still not clear. Since liver is their common target, in this study, the individual and combined toxicity of DDT and Cd in human liver carcinoma HepG2 and human normal liver THLE-3 cell lines were investigated. The results showed that DDT and Cd inhibited the viability of HepG2 and THLE-3 cells dose-dependently and altered lysosomal morphology and function. Intracellular reactive oxygen species and lipid peroxidation levels were induced by DDT and Cd treatment. The combined cytotoxicity of DDT and Cd was greater than their individual cytotoxicity, and the interaction between Cd and DDT was additive on the inhibition of cell viability and lysosomal function of HepG2 cells. The interaction was antagonistic on the inhibition of cell viability of THLE-3 cells. These results may facilitate the evaluation of the cumulative risk of pesticides and heavy metal residues in the environment.


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