Fish tissue metals and zooplankton assemblages of northeastern U.S. lakes

1998 ◽  
Vol 55 (2) ◽  
pp. 339-352 ◽  
Author(s):  
Richard S Stemberger ◽  
Celia Y Chen
Keyword(s):  
Heavy Metals ◽  
Urban Areas ◽  
Regression Models ◽  
Forest Cover ◽  
Geographic Location ◽  
Fish Tissue ◽  
Significant Negative Correlation ◽  
Structural Features ◽  
Trophic Levels ◽  
Structural Variables

Temperature, chlorophyll a, proportion of forest cover on the watershed, and fish tissue Pb, Zn, and Hg concentrations were the primary gradients that best explained the patterns of distribution of zooplankton assemblages in 38 northeastern U.S. lakes. Different zooplankton assemblages were associated with lakes that contained trout or cool-water species of minnows and systems dominated by a variety of warmwater fish species. Heavy metals in fish varied widely with geographic location and proximity to urban areas. Regression models indicated that Zn and Hg in fish were significantly and positively associated with chain length of the zooplankton web. In contrast, these metals and As showed a significant negative correlation with the number of feeding links between species. Structurally complex pelagic webs, comprising many lateral links, may significantly attenuate the transfer of heavy metals to higher trophic levels. Stepwise regression models that included structural variables significantly improved the amount of explainable variance in the fish metal concentrations over those with only physicochemical and land use variables. This study suggests that the high variability of metals in fish observed between adjacent lakes and across the region is explained in part by the structural features of the zooplankton web.

scholarly journals CONTAMINATION BY HEAVY METALS AND ITS CONSEQUENCES: REFLECTIONS

2020 ◽  
Vol 3 (1) ◽  
pp. 101
Author(s):  
Gabrielle Diniz dos Santos ◽  
Gil Dutra Furtado ◽  
Cíntia Cleub Neves Batista
Keyword(s):  
Heavy Metals ◽  
Urban Areas ◽  
Memory Loss ◽  
Trophic Levels ◽  
Low Fertility ◽  
Free Form ◽  
Dissolved Metals ◽  
Physiological Factors ◽  
The Central Nervous System ◽  
Anthropic Influence

Nowadays, the vast majority of aquatic bodies suffer some kind of anthropic influence due to the great expansion of urban areas and consequently industrial areas, with the pollution coming into such environments. One of the types of pollutants present in the environment are heavy metals, which are found naturally in water bodies due to the weathering of rocks and volcanic activities. The present work is of bibliographic nature, based on searches in the bibliography pertinent to the theme. It is possible to state that with anthropic intervention, such metals become common and are found in greater quantities in the environment in a free form. Thus, some of the most common sources of release of heavy metals into the environment are fertilizers, pesticides, coal and oil combustion, vehicular emissions, mining, smelting, refinement and incineration of urban and industrial waste. Thus making contamination of humans with heavy metals more and more common, one of the most common and easy forms of contamination is through food. The absorption of metals by animals can occur in two ways, bioaccumulation and biomagnification. The first occurs through the diffusion or ingestion of the dissolved metals in the water, which occur through the gills or the digestive tract and then lodges in the animals' tissues, so that the organism cannot absorb it, thus obtaining a bioaccumulative character. In the trophic biomagnification or magnification, the concentration of metals in the organism occurs gradually through the trophic levels. The transfer of contaminants through the food chain characterizes such a process that passes from producers to consumers and the longer the chain, the greater the concentration on the final consumer. Therefore, we can emphasize that the concentration and absorption content of such substances are relative and depend on several environmental and physiological factors that vary between species of beings. Metal poisoning can cause serious damage, such as low fertility, decreased immune defenses, reduced growth rate and pathologies that can lead to senescence. Metals can cause different problems in humans, most of which are of a motor nature, as they directly affect the central nervous system (CNS), and can cause memory loss, uncontrolled limb tremors, muscle atrophy, kidney injuries, among others.

Cannabis use in Switzerland: The role of attribution of drug use to friends, urbanization and repression 1The study was supported by the Swiss Federal Office of Public Health (Bundesamt für Gesundheit BAG) Grant 316.96.5980.

2001 ◽  
Vol 60 (2) ◽  
pp. 99-107 ◽  
Author(s):  
Holger Schmid
Keyword(s):  
Drug Use ◽  
Urban Areas ◽  
Hierarchical Linear Model ◽  
Cannabis Use ◽  
School Aged Children ◽  
Structural Variables ◽  
Hbsc Study ◽  
Nationally Representative ◽  
Highly Correlated ◽  
Individual Use

Cannabis use does not show homogeneous patterns in a country. In particular, urbanization appears to influence prevalence rates, with higher rates in urban areas. A hierarchical linear model (HLM) was employed to analyze these structural influences on individuals in Switzerland. Data for this analysis were taken from the Switzerland survey of Health Behavior in School-Aged Children (HBSC) Study, the most recent survey to assess drug use in a nationally representative sample of 3473 15-year-olds. A total of 1487 male and 1620 female students indicated their cannabis use and their attributions of drug use to friends. As second level variables we included address density in the 26 Swiss Cantons as an indicator of urbanization and officially recorded offences of cannabis use in the Cantons as an indicator of repressive policy. Attribution of drug use to friends is highly correlated with cannabis use. The correlation is even more pronounced in urban Cantons. However, no association between recorded offences and cannabis use was found. The results suggest that structural variables influence individuals. Living in an urban area effects the attribution of drug use to friends. On the other hand repressive policy does not affect individual use.

scholarly journals Contrasting responses of above- and belowground diversity to multiple components of land-use intensity

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Gaëtane Le Provost ◽  
Jan Thiele ◽  
Catrin Westphal ◽  
Caterina Penone ◽  
Eric Allan ◽  
...  
Keyword(s):  
Land Use ◽  
Forest Cover ◽  
Spatial Scales ◽  
Biodiversity Loss ◽  
Trophic Levels ◽  
Land Use Intensity ◽  
Trophic Groups ◽  
Multiple Components ◽  
Belowground Diversity ◽  
Landscape Level

AbstractLand-use intensification is a major driver of biodiversity loss. However, understanding how different components of land use drive biodiversity loss requires the investigation of multiple trophic levels across spatial scales. Using data from 150 agricultural grasslands in central Europe, we assess the influence of multiple components of local- and landscape-level land use on more than 4,000 above- and belowground taxa, spanning 20 trophic groups. Plot-level land-use intensity is strongly and negatively associated with aboveground trophic groups, but positively or not associated with belowground trophic groups. Meanwhile, both above- and belowground trophic groups respond to landscape-level land use, but to different drivers: aboveground diversity of grasslands is promoted by diverse surrounding land-cover, while belowground diversity is positively related to a high permanent forest cover in the surrounding landscape. These results highlight a role of landscape-level land use in shaping belowground communities, and suggest that revised agroecosystem management strategies are needed to conserve whole-ecosystem biodiversity.

P055 Title: Standard rate of ASLO in healthy children with streptococcal (angina) or post-streptococcal (RAA) infection in Morocco

Rheumatology ◽  
2021 ◽  
Vol 60 (Supplement_5) ◽  
Author(s):  
Himri Sara ◽  
Oumokhtar Bouchra ◽  
El Fakir Samira ◽  
Atmani Samir
Keyword(s):  
Urban Areas ◽  
Geographic Location ◽  
Cross Sectional Study ◽  
Critical Threshold ◽  
Healthy Children ◽  
Age Group ◽  
Normal Children ◽  
Cross Sectional ◽  
Standard Rate ◽  
Group 2

Abstract Background The antistreptolysins O “ASLO” are anti streptococcal antibodies directed against streptolysin O. The assay of ASLO can provide proof of infection of streptococcal origin. However, it cannot confirm the presence of RAA or the degree of severity of the disease. A level of ASLO less than or equal to a critical threshold of 200 IU/ml is considered normal in children. Several factors influence the ASLO title and therefore their standard rate such as age, geographic location and seasonal variation. The objective of this study is to determine the upper normal limit (ULN) of ASLO in healthy children with angina or RAA at the CHU Hassan II of Fez in Morocco. Methods This is a cross-sectional study carried out from January 2016 to July 2019 in the cardiopediatric unit of CHU Hassan II and the Anarjiss health center in Fez. Patients below 18 years of age were included in this study. The children are classified into 3 groups: group 1: 152 children with RAA and who are diagnosed according to the modified Jones criteria, group 2: 177 children with angina, group 3: 157 healthy children who did not have an RAA, a history of recurrent or recent pharyngitis. Patient data is collected on operating sheets. Statistical analysis was performed using SPSS v 21 software. To establish a normal upper limit for ASLOs, the 90 percentile was used as it is a value below which at least 90% of cases studied in each group. Results The most common age group in the 3 groups is the age group between 5 and 15 years old. The frequency of children of urban origin is greater than that of rural origin in all the groups studied. The ULN is 421.4U/ml in the group of normal children, 641.95 U/ml in the RAA group and 561.8 U/ml in the group of children with pharyngitis. The study of changes in ASLO rates over time shows that they increase significantly in angina and tend to decrease in RAA. The LSN of ASLOs by gender shows that it is higher for boys than for girls. The ULN according to the residence shows that it is higher in urban areas. As well as the LSN of ASLO according to the season shows that it is higher in the cold period, especially in winter and spring (P < 0.001). With regard to age, the ULN of ASLOs is higher in the 5–15 age group. Conclusion In this study, it can be concluded that an ASLO level less than or equal to 400 U/ml is the critical threshold in a normal child, while an ASLO level >400 U/ml is considered pathological in children. children in Morocco.

Lightweight aggregates to reduce heavy metal pollution in green infrastructure for urban stormwater management

2021 ◽  
Author(s):  
Concepcion Pla ◽  
Javier Valdes-Abellan ◽  
Miguel Angel Pardo ◽  
Maria Jose Moya-Llamas ◽  
David Benavente
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Green Infrastructure ◽  
Metal Pollution ◽  
Heavy Metal Pollution ◽  
Urban Areas ◽  
Stormwater Management ◽  
Lightweight Aggregates ◽  
Urban Stormwater ◽  
Runoff Water

<p>The impervious nature of urban areas is mostly responsible for urban flooding, runoff water pollution and the interception of groundwater recharge. Green infrastructure and sustainable urban drainage systems combine natural and artificial measures to mitigate the abovementioned problems, improving stormwater management and simultaneously increasing the environmental values of urban areas. The actual rate of urban growth in many urban areas requires the enhancement and optimization of stormwater management infrastructures to integrate the territorial development with the natural processes. Regarding the quality of runoff stormwater, heavy metals are critical for their impact on human health and ecological systems, even more if we consider the cumulative effect that they produce on biota. Thus, innovative stormwater management approaches must consider new solutions to deal with heavy metal pollution problems caused by runoff. In this study, we propose the employment of Arlita<sup>®</sup> and Filtralite<sup>®</sup>, two kind of lightweight aggregates obtained from expanded clays, to remove heavy metal concentration from runoff stormwater. Laboratory experiments were developed to evaluate the removal rate of different heavy metals existent in runoff stormwater. The lightweight aggregates acted as filter materials in column experiments to quantify their removal capacity. In addition, batch tests were also developed to evaluate the exhaustive capacity of the materials. Results from the study confirmed the efficiency of the selected lightweight aggregates to reduce the heavy metals concentration by up to 90% in urban stormwater runoff.</p>

Can management improve the lawn’s functioning in the conditions of multiple anthropogenic stressors?

2021 ◽  
Author(s):  
Olga Gavrichkova ◽  
Dario Liberati ◽  
Viktoriya Varyushkina ◽  
Kristina Ivashchenko ◽  
Paolo De Angelis ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Soil Respiration ◽  
Green Infrastructure ◽  
Urban Areas ◽  
Ecosystem Respiration ◽  
Heterotrophic Respiration ◽  
Sand Mixture ◽  
Anthropogenic Stressors ◽  
Unplanted Soil ◽  
The Impact

<p>Release of heavy metals, salts and other toxic agents in the environment is of increasing concern in urban areas. Contaminants not solely decline the quality of the local environment and affect the health of human population and urban ecosystems but are also spread through runoff and leaching into non-contaminated areas. Urban lawns are the most distributed green infrastructure in the cities. Management of lawn system may either exacerbate the negative effects of contaminants on lawn functioning either help to withstand the toxic effects and maintain the lawn ecosystem health and the efficient release of ecosystem services.  </p><p>The aim of this study was to evaluate the interactions between the lawn management, the lawn functioning, and the release into the soil of typical urban contaminants. For this purpose, <em>Festuca arundinacea</em> grass was planted in a turf-sand mixture with and without amendment addition (zeolite + vermicompost). To reproduce the impact of traffic-related contaminants in proximity of the road, pots were treated with a solution containing de-icing salt (NaCl) and 6 heavy metals (Zn, Cd, Pb, Cr, Cu, Ni), imitating road runoff solution. After contamination, half of pots was maintained at optimum soil water content (Smart irrigation), another half was left to periodical drying in order to simulate conditions with discontinuous watering (Periodical irrigation). The same experimental scheme was reproduced for unplanted soil. CO<sub>2</sub> net ecosystem exchange (NEE), soil and ecosystem respiration as well as flux from unplanted soil (heterotrophic respiration) were measured shortly after the treatment (short-term) and up 3 months since the treatment start (long-term).</p><p>Soil amendment stimulated plant productivity and increased the efficiency of the system in C uptake (+56% NEE). A relevant reduction of NEE was observed from 14 to 40 days after the application of traffic-related contaminants in both amended and non amended pots. During this period the contaminants had the greatest impact on lawn NEE subjected to Periodic irrigation (-49% and -66% in amended and non amended pots, respectively), while lawn under Smart irrigation was less affected (-35% and -26% in amended and non amended pots, respectively). Different respiration sources (ecosystem respiration, soil respiration, heterotrophic respiration) were characterized by different sensitivity to management and contamination. Heterotrophic flux was not sensitive to soil amending but declined with contamination with enhanced negative effect under Smart irrigation. Response of ecosystem respiration to contamination was less pronounced in confront to soil respiration suggesting leaf-level buffering.    </p><p>Three months later,  the effect of contaminants on lawn gas exchange ceased for all treated pots. Instead, the irrigation effect persisted depending on whether pots were amended or not. In non amended pots NEE was reduced by 18% under Periodic irrigation, while this effect was not present in amended pots. We conclude, that performance of such green infrastructure as lawns in terms of C sequestration under multiple anthropogenic stressors could be efficiently improved through soil amending and irrigation control.</p><p>Current research was financially supported by RFBR No. 19-29-05187 and RSF No. 19-77-30012.</p>

scholarly journals Relief influence on the spatial distribution of the Atlantic Forest cover on the Ibiúna Plateau, SP

2007 ◽  
Vol 67 (3) ◽  
pp. 403-411 ◽  
Author(s):  
WG. Silva ◽  
JP. Metzger ◽  
S. Simões ◽  
C Simonetti
Keyword(s):  
Atlantic Forest ◽  
Urban Areas ◽  
Large Scale ◽  
Forest Cover ◽  
Agricultural Land ◽  
Environmental Gradients ◽  
Aerial Photographs ◽  
General Distribution ◽  
Successional Stage ◽  
Slope Orientation

Several studies suggest that, on a large scale, relief conditions influence the Atlantic Forest cover. The aim of this work was to explore these relationships on a local scale, in Caucaia do Alto, on the Ibiúna Plateau. Within an area of about 78 km², the distribution of forest cover, divided into two successional stages, was associated with relief attribute data (slope, slope orientation and altitude). The mapping of the vegetation was based on the interpretation of stereoscopic pairs of aerial photographs, from April 2000, on a scale of 1:10,000, while the relief attributes were obtained by geoprocessing from digitalized topographic maps on a scale of 1:10,000. Statistical analyses, based on qui-square tests, revealed that there was a more extensive forest cover, irrespective of the successional stage, in steeper areas (>10 degrees) located at higher altitudes (>923 m), but no influence of the slope orientation. There was no sign of direct influence of relief on the forest cover through environmental gradients that might have contributed to the forest regeneration. Likewise, there was no evidence that these results could have been influenced by the distance from roads or urban areas or with respect to permanent preservation areas. Relief seems to influence the forest cover indirectly, since agricultural land use is preferably made in flatter and lower areas. These results suggest a general distribution pattern of the forest remnants, independent of the scale of study, on which relief indirectly has a strong influence, since it determines human occupation.

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