scholarly journals A paleolimnological archive of metal sequestration and release in the Cumberland Basin Marshes, Atlantic Canada

FACETS ◽  
2017 ◽  
Vol 2 (1) ◽  
pp. 440-460 ◽  
Author(s):  
Dewey W. Dunnington ◽  
Hilary White ◽  
Ian S. Spooner ◽  
Mark L. Mallory ◽  
Chris White ◽  
...  
Keyword(s):  
Environmental Changes ◽  
Fossil Fuel Combustion ◽  
Multiple Sources ◽  
Aquatic Life ◽  
Metal Sequestration ◽  
Pb Contamination ◽  
Metal Levels ◽  
Aquatic Sediment ◽  
Level Lowering ◽  
Sediment Contaminant

We used a paleolimnological approach at Long Lake, Nova Scotia, to construct a 10 500-year record of metal deposition in lakebed sediments and elucidate the influence of both natural and anthropogenic environmental changes. Aquatic sediment concentrations of mercury (Hg), arsenic (As), and chromium (Cr) in Long Lake fluctuated substantially and, during some periods, exceeded guidelines for the protection of aquatic life. Increases in lead (Pb), Hg, Cr, trace metals, and nitrogen stable isotopes (δ15N) were broadly coincident with a period of widespread drying from ca. 8000 to 4000 cal BP and were likely a consequence of regional fires. From ca. 4000 cal BP until 1700 AD, metal levels in general were low due to decreased erosion, increased precipitation, and reduced fire activity. Water level lowering and forced sediment aggradation (tiding) in the 1800s led to increases in minerogenic Pb and Cr, though fossil fuel combustion also likely contributed to total Pb concentrations. Stratigraphic proxies indicated increased inorganic sedimentation rates, and reduced autochthonous productivity were coincident with lower Hg and As concentrations in the Long Lake sediment. Our data indicate that natural phenomena (fire) can result in sediment contaminant exceedances, that most metals have multiple sources, and that both human-induced disturbance and emissions have contributed to Pb contamination in the last 200 years. In addition, wetter and generally cooler climate appeared to favour lower concentrations of contaminants in lake sediments. Although wetland sediments in the Cumberland Basin Marshes are not heavily polluted with metals, the development of constructed wetlands and the disruption of aquatic sediments have the potential to concentrate, mobilize, and increase the bioavailability of metals.

scholarly journals Evaluating the Atibaia River Hydrology using JULES6.1

2021 ◽  
Author(s):  
Hsi-Kai Chou ◽  
Ana Maria Heuminski de Avila ◽  
Michaela Bray
Keyword(s):  
Land Surface ◽  
Environmental Changes ◽  
Water Flux ◽  
Model Performance ◽  
Reanalysis Data ◽  
Agricultural Activity ◽  
Multiple Sources ◽  
Metropolitan Regions ◽  
River Hydrology

Abstract. Land surface models such as the Joint UK Land Environment Simulator (JULES) are increasingly used for hydrological assessments because of their state-of-the-art representation of physical processes and versatility. Unlike statistical models and AI models, the JULES model simulates the physical water flux under given meteorological conditions, allowing us to understand and investigate the cause and effect of environmental processes changes. Here we explore the possibility of this approach using a case study in the Atibaia river basin, which serves as a major water supply for metropolitan regions of Campinas and São Paulo, Brazil. The watershed is suffering increasing hydrological risks, which could be attributed to environmental changes, such as urbanization and agricultural activity. The increasing risks highlight the importance to evaluate the land surface processes of the watershed systematically. We explore the use of local precipitation collection complement with multiple sources of global reanalysis data to simulate the basin hydrology. Our results show that the coarse resolution of rainfall data is the main reason to reduce model performance. Despite this shortcoming, key hydrological fluxes in the basin can be represented by the JULES model simulations.

Tracking Recent DDT Contamination in a Northern New England Watershed

2021 ◽  
Author(s):  
Amanda May ◽  
Lisa Doner ◽  
Jeremiah Duncan ◽  
Stephen Hill
Keyword(s):  
New England ◽  
New Hampshire ◽  
Sediment Quality ◽  
Source Area ◽  
Daughter Product ◽  
Multiple Sources ◽  
Aquatic Life ◽  
Quality Guidelines ◽  
Northern New England ◽  
Lake Deposits

Abstract Ecological research since 2005 into potential causes of declines in loon population at Squam Lake, New Hampshire, U.S.A., revealed multiple potential causes, but no particular source of contaminants. In 2017, tributary sediment analyses revealed specific sub-watersheds transporting contaminants to the lake (Vogel, 2019). For this study, from 2018 to 2020, we used an approach to this problem that allowed for rapid source area determination of DDT using soil and sediment analyses. We find modern presence of p,p’ isomers of DDT and DDE within the Bennett Brook sub-watershed, arising from 60-year-old orchard applications and a former barn. Highest concentrations, 723 μg/kg p,p’ DDT and 721 μg/kg p,p’ DDE, occur near the barn’s foundation rubble. DDT exceeds that of the daughter product, DDE, in some of the sub-watershed’s soils, including but not limited to the barn site. In the soils where DDT>DDE, we infer delayed breakdown of DDT. DDT<DDE occurs in the streambed and lake deposits, as well as some soils. A Pb-210 dated sediment core, collected near the outlet of Bennet Brook, shows continuous accumulation of the daughter products, DDE and DDD, from 1951 to the present. Residuals are derived from multiple sources within the sub-watershed, including orchard soils, the barn site, and sediment accumulations in the stream. These DDT residues fall below mandatory soil remediation levels for the State of New Hampshire, but exceed some sediment quality guidelines for protection of aquatic life. Bioaccumulation of p,p’ DDE is evident in crayfish that reside in Bennett Brook.

Distribution of Trace Metals in Vertebrate and Invertebrate Species from Ubeji Creek, Southern Nigeria

2014 ◽  
Vol 1 (1) ◽  
pp. 16-24
Author(s):  
G.C.C Ndinwa ◽  
M Peretomode ◽  
T Asiagbe
Keyword(s):  
Trace Metals ◽  
Clarias Gariepinus ◽  
Whole Body ◽  
Aquatic Life ◽  
Invertebrate Species ◽  
Metal Levels ◽  
Lead Zinc ◽  
Arsenic Copper ◽  
Cadmium Zinc ◽  
Construction Works

Trace metals content in water, fishes (Tilapia mariae, Clarias gariepinus), earthworm (Libydrius violaceous) and sediment were determined from Ubeji River using Atomic Absorption Spectrophotometer (AAS). Metals determined were lead, cadmium, zinc, mercury, arsenic, copper and Iron. The results obtained revealed that all the metals were detected. Also, there were variations in metal levels in the samples. Highest Zn level was obtained in all the samples analysed (0.284ppm and 0.284ppm in water, 24.0mg/kg in Clarias gariepinus, 28.8mg/kg in Tilapia mariae, 1.16mg/kg in earthworm and 0.64mg/kg in sediment). The concentrations of trace metals obtained in this study are found to be dangerous. The metal levels in water from Ubeji River are higher than the WHO/FEPA standards for water quality. The concentrations of lead, zinc and copper obtained in the whole body of fishes exceeded the WHO/FEPA set standards for aquatic life. The presence of trace metals found in the sample from Ubeji River is attributed to the proximity of petroleum activity, construction works and other allied companies.

Assessment of zinc and lead concentration in water and muscles of Labeo rohita collected from wild and local fish farms of Pakistan

2017 ◽  
Author(s):  
Khalid Mahmood Anjum ◽  
Atif Yaqub ◽  
Ehsan Mehmood Bhatti ◽  
Muhamad Yameen ◽  
Muhammad Sharif Mughal ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Labeo Rohita ◽  
Heavy Metal Concentration ◽  
Water Bodies ◽  
Fish Farms ◽  
Aquatic Life ◽  
Metal Levels ◽  
The Government ◽  
Local Water

Reasonable evidences suggest that heavy metal pollutants have been added by factories and other industries to our local water bodies. The present study was conducted to determine the heavy metal (zinc and lead) concentrations in muscle tissues of Labeo rohita inhabiting local water bodies as well as those being raised at farms. Sampling was performed to collect Labeo rohita from two different stations along river Ravi, viz. Lahore Siphon (upstream) and Balloki Headworks (downstream). Additionally, samples were also obtained from the government operated as well as private fish farms located in Lahore District, Pakistan. The fish were dissected; their muscles were digested, filtered, and finally analyzed for concentrations of Zn and Pb. Significant variation of heavy metal ions were observed between two sites along river Ravi as well as government operated and private fish farms. Significantly high mean concentrations of Zn (10.7±1.268) and Pb (0.61±0.082) were observed at Balloki Head-works; whereas, the lowest Zn (1.58±0.235) and Pb (0.16±0.008) heavy metal levels were recorded in the muscle samples collected from private fish farms. It was also observed that the heavy metal concentration in the muscles of Labeo rohita, collected from Balloki Head-works was much higher than the permissible limits laid down by WHO/FAO. Further the recorded highest level of heavy metals in water samples collected from River Ravi indicates that the bioaccumulation of heavy metals is severely affecting the aquatic life of fresh water and industries should not be allowed to release their effluent directly into the river Ravi in their vicinity.

scholarly journals Contamination Assessment of Heavy Metals in Agricultural Soil, in the Liwa Area (UAE)

Toxics ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 53 ◽  
Author(s):  
Ahmed A. Al-Taani ◽  
Yousef Nazzal ◽  
Fares M. Howari ◽  
Jibran Iqbal ◽  
Nadine Bou Orm ◽  
...  
Keyword(s):  
Heavy Metals ◽  
United Arab Emirates ◽  
Ecological Risk ◽  
Agricultural Soils ◽  
Pollution Load Index ◽  
Soil Samples ◽  
Multiple Sources ◽  
Contamination Assessment ◽  
Pollution Levels ◽  
Metal Levels

The Liwa area is a primary food production area in the United Arab Emirates (UAE) and has intensively been used for agriculture. This study investigates the pollution levels with heavy metals in agricultural soils from the Liwa area. Thirty-two soil samples were analyzed for Mn, Zn, Cr, Ni, Cu, Pb, Cd, Co, and As. Results revealed that heavy metal levels varied in the ranges 220.02–311.21, 42.39–66.92, 43.43–71.55, 32.86–52.12, 10.29–21.70, 2.83–8.84, 0.46–0.69, 0.03–0.37 mg/kg for Mn, Zn, Cr, Ni, Cu, Pb, Cd, Co, and As, respectively. All samples presented low As concentrations with an average of 0.01 mg/kg. The variations in bulk metal contents in the soil samples were related to multiple sources, including agrochemicals, atmospheric dust containing heavy metals, and traffic-related metals. Enrichment factor analysis indicates that Cd, Ni, Zn, and Cr were highly enriched in soils, and they could originate from non-crustal sources. Based on the geo-accumulation index (Igeo), the soil samples appeared uncontaminated with Mn, Cr, Zn, Pb, Co, As, Cu, uncontaminated to moderately contaminated with Ni and moderately contaminated with Cd. The contamination factors suggest low contamination, except for Ni, which showed moderate contamination. The average pollution load index (PLI) revealed unpolluted to low pollution of all soil samples. The ecological risk assessment (PERI) showed that all heavy metals posed a low risk, except for Cd which exhibited a high ecological risk.

scholarly journals Leachates and physicochemical characteristics of Rumuodumaya dumpsites, Niger-Delta, Nigeria

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Surface Water ◽  
Niger Delta ◽  
Physicochemical Characteristics ◽  
Safe Drinking Water ◽  
Solid Waste Disposal ◽  
Measurement Standard ◽  
Aquatic Life ◽  
Standard Procedures ◽  
Metal Levels

The physicochemical characteristics and heavy metal levels of leachates at the Rumuodumaya dumpsites and the surface water of its adjacent river was investigated by appropriate field instrument for in situ measurement, standard procedures and AGILENT 55B spectra for the heavy metals. The results from the dumpsites and surface water of the river generally indicate that as of the time of analysis, there is no serious threat to its immediate environment except the nickel concentrations in the dumpsites and surface water of the river, respectively and whose values were beyond the recommended limit of WHO/USEPA (0.05 mg/L) for safe drinking water. The trend of the results also indicates that the dumpsites are sources of numerous soil and water pollutants capable of depleting oxygen levels in the river and this could pose several and serious health risk to humans and aquatic life. Adequate solid waste disposal technique should be adopted by the appropriate agency to forestall this threat to the Rumuodumaya environment.

scholarly journals Estimating Microbial Diversity via Morphological Based Microscopic Image Analysis: Methods and Metrics

2020 ◽  
Vol 14 (4) ◽  
pp. 2757-2767
Author(s):  
Anaahat Dhindsa ◽  
Sanjay Bhatia ◽  
Sunil Agrawal ◽  
B.S. Sohi
Keyword(s):  
Image Processing ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Research Work ◽  
Primary Data ◽  
Multiple Sources ◽  
Aquatic Life ◽  
Sources Of Pollution ◽  
Image Processing Algorithms ◽  
Processing Algorithms

To accelerate the monitoring and counting of biodiversity of various species, there is a need for automating the process of computing biodiversity. The calculations of the alpha and beta biodiversity indexes are fundamental for the analysis of ecological and biodiversity studies. Sukhna and Dhanas lakes, India are critical for the maintenance of the health of the residents and aquatic life thriving in them. Both lakes are prone to pollution. Due to these factors, there is a need for building digitized infrastructure for monitoring the health of these lakes. Hence in this research work, an automated algorithm has been devised for the computation of biodiversity of microorganisms. The work focuses on the surface water of both these lakes. The automation of biodiversity computation is done with image processing algorithms and is applied to the primary data collected. From this study, it is apparent that the counting of microorganisms using image processing algorithms is an easier and efficient way for biodiversity studies as compared to the manual process of estimating the population of microbes. The results show that the species richness of Dhanas Lake is more as compared to Sukhna Lake. The dissimilarity between the two lakes is five species as per the primary data collected. This shows that the biodiversity of Dhanas Lake is better than the Sukhna Lake but it is prone to harmful algal blooms. This may be attributed to the fact that Dhanas Lake may have multiple sources of pollution that need to be identified.

scholarly journals Towards sustainable community conservation in tropical savanna ecosystems: a management framework for ecotourism ventures in a changing environment

2020 ◽  
Author(s):  
Boycen Kumira Mudzengi ◽  
Edson Gandiwa ◽  
Never Muboko ◽  
Chiedza Ngonidzashe Mutanga
Keyword(s):  
Climate Change ◽  
Natural Resources ◽  
Environmental Changes ◽  
Population Increase ◽  
Community Conservation ◽  
Feedback Systems ◽  
Multiple Sources ◽  
Changing Environment ◽  
Management Framework ◽  
Depth Analysis

AbstractThe sustainability of ecotourism ventures under the Community Based Natural Resources Management in Zimbabwe is under stress due to environmental changes emanating from effects associated with socioeconomic factors, climate change and epidemic diseases. Using an in-depth analysis of the Mahenye ecotourism venture from the year 1982 to 2020 as a case study, this study sought to propose a management framework for ecotourism ventures in a changing environment by examining the sustainability of community conservation initiatives in Zimbabwe. Research methods included expert opinion from two natural resources governance academics, desktop research and authors’ experiences about Mahenye ecotourism venture. Results indicated that the Mahenye ecotourism venture has faced significant challenges but has been resilient to withstand the shocks such as population increase, exclusion of youths and women, climate change, hyperinflation, donor fatigue, reduced international ecotourist visitation and international hunting bans emanating from socioeconomic and political environmental changes. These shocks have a negative effect on the main elements of an ecotourism venture such as the wildlife resources, amenities, attraction, accessibility, management system, marketing, beneficiaries and linkages. The management framework highlights the interventions that can be made to enable ecotourism ventures in changing environments to remain sustainable. The interventions are promoting strong community cohesion, developing sustainable self-funding mechanisms, promoting multiple sources of income, carrying targeted environmental education programs, capacity building in managing ecotourism in periods of hyperinflation, improved marketing and offering a unique experience, promoting climate smart ecotourism, promoting domestic ecotourism visits, implementing effective feedback systems among stakeholders to decrease uncertainties and lobbying to have hunting bans removed.

scholarly journals Leachates and physicochemical characteristics of Rumuodumaya dumpsites, Niger-Delta, Nigeria

2019 ◽  
Author(s):  
Chem Int ◽  
Godson Ndubuisi Iwuoha
Keyword(s):  
Surface Water ◽  
Niger Delta ◽  
Physicochemical Characteristics ◽  
Safe Drinking Water ◽  
Solid Waste Disposal ◽  
Measurement Standard ◽  
Aquatic Life ◽  
Standard Procedures ◽  
Metal Levels

The physicochemical characteristics and heavy metal levels of leachates at the Rumuodumaya dumpsites and the surface water of its adjacent river was investigated by appropriate field instrument for in situ measurement, standard procedures and AGILENT 55B spectra for the heavy metals. The results from the dumpsites and surface water of the river generally indicate that as of the time of analysis, there is no serious threat to its immediate environment except the nickel concentrations in the dumpsites and surface water of the river, respectively and whose values were beyond the recommended limit of WHO/USEPA (0.05 mg/L) for safe drinking water. The trend of the results also indicates that the dumpsites are sources of numerous soil and water pollutants capable of depleting oxygen levels in the river and this could pose several and serious health risk to humans and aquatic life. Adequate solid waste disposal technique should be adopted by the appropriate agency to forestall this threat to the Rumuodumaya environment.

Sign in / Sign up

Export Citation Format

Share Document