scholarly journals ASPECTOS GEOQUÍMICOS Y AMBIENTALES DE LOS SEDIMENTOS DEL RÍO CUCHIVERO, VENEZUELA.

2016 ◽  
Author(s):  
Arístide Márquez ◽  
Gregorio Martínez ◽  
Julio Figuera ◽  
Ivis Fermín ◽  
William James Senior ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Organic Matter ◽  
Organic Carbon ◽  
Total Phosphorus ◽  
River Sediments ◽  
Point Of View ◽  
Poor Correlation ◽  
The Poor ◽  
Del Rio ◽  
Nitrogen Phosphorus

This paper reports the geochemical characteristics and environmental conditions of Cuchivero river sediments in Venezuela, depending on particle size, organic matter, organic carbon, nitrogen and total phosphorus, carbonates and heavy metals. The granulometry was typified by a predominance of sands with low organic matter (0.52 to 0.87%), organic carbon (0.06 to 0.09%) and carbonates content (0.54 to 2.61%) as well as high values of total nitrogen (602-985 mg / kg). The poor correlation between nitrogen, phosphorus and organic matter, suggests presence of nitrogen and total phosphorus of allochthonous origin and no Redfield organic matter. The average heavy metals in mg/kg, showed a descending concentration gradient, Fe (410)> Mn (63.14)> Zn (9.01)> Ni (3.38)> (2.21Cu)> Cr (2.09)> Co (1.13)> Cd (0.21) > Pb (0.07) mg / kg, with an association to the sands and carbonates, suggesting lithogenic origin. From the environmental point of view, there is no evidence of anthropogenic impact, as reflected by levels of organic matter and heavy metals which are below of the permissible values.

scholarly journals Differentiation of digestion method for heavy metals in river sediments based on organic matter gradients

2020 ◽  
Vol 467 ◽  
pp. 012128
Author(s):  
Jinbao Liu ◽  
Qiu Shen ◽  
Fang Wei ◽  
Zhenni Guo ◽  
Yingjie Tian
Keyword(s):  
Heavy Metals ◽  
Organic Matter ◽  
River Sediments ◽  
Digestion Method

scholarly journals Study of Algal Organic Matter Removal Efficiency Using a Newly Developed Removal System

2020 ◽  
Vol 13 ◽  
pp. 117862211989842
Author(s):  
Hwan Kim ◽  
Inseol Yeo ◽  
Chan-Gyu Park
Keyword(s):  
Organic Matter ◽  
South Korea ◽  
Chlorophyll A ◽  
Total Phosphorus ◽  
Removal Rate ◽  
Continuous System ◽  
Oyster Shell ◽  
Point Of View ◽  
Algal Organic Matter ◽  
Removal System

Water sources are currently facing great challenges from rapid population growth and industrial developments. Investigations into how to remove algal organic matter (AOM) are thus of great importance from an environmental point of view because most lakes and reservoirs in South Korea suffer from algae problems, especially in the summer. Many efforts have been made to remove AOM from the aquatic environment in South Korea. In this study, we focus on development of a new AOM removal system, utilizing waste oyster shells and ferrihydrite as the media of the filtration system. Using this system, the removal rate of AOM was investigated regarding the concentrations of chlorophyll a, total phosphorus, and alginate. It was found that about 92% of the total phosphorus was removed through this system when raw oyster shell powders were heated at 900°C to convert them into calcium oxide powders. The use of a continuous system also led to a reduction of 94.2% in total phosphorus, 78.8% in chlorophyll a, and 43.6% in alginate.

Multivariate analyses on heavy metal binding fractions of river sediments in Southern Taiwan

2000 ◽  
Vol 42 (7-8) ◽  
pp. 193-199 ◽  
Author(s):  
K. C. Yu ◽  
C. Y. Chang ◽  
L. J. Tsai ◽  
S. T. Ho
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Organic Matter ◽  
Metal Binding ◽  
River Sediments ◽  
Principal Component ◽  
Fe Oxides ◽  
Data Points ◽  
Southern Taiwan ◽  
Highly Correlated

This study depicts the amounts of heavy metals (Cu, Zn, Pb, Cr, Co, and Ni) bound to four geochemical compositions of sediments (carbonates, Mn oxides, Fe oxides, and organic matters), and the correlations between various geochemical compositions and their heavy-metal complexes. Hundreds of data, obtained from sediments of five main rivers (located in southern Taiwan), were analyzed by using multivariate analysis method. Among the four different geochemical compositions, the total amount of the six heavy metals bound to organic matter is the highest. Zn is easily bound to various geochemical compositions, especially carbonates in sediments of the Yenshui river and the Potzu river (i.e., the heavily heavy-metal polluted sediments); Cr, Pb, and Ni are mainly bound to both Fe oxides and organic matter; Cu has high affinity to organic matter. By performing principal component analyses, the data points of organic matter and both Pb and Cu associated with organic matter cluster together in sediments ofthe Peikang, the Potzu, and the Yenshui rivers, which indicates both Pb and Cu might be discharged from the same pollution sources in these rivers. Moreover, correlations between any two binding fractions of heavy metal associated with Fe oxides in different rivers are not consistent, which indicates some factors including the binding sites of Fe oxides, the extent of heavy metal pollution, binding competitions between heavy metals may affect the amounts of heavy metals bound to Fe oxides. Furthermore, it should be noted that the amount of Pb bound to Fe oxides is highly correlated with the amount of Fe oxides in sediments of the Peikang, the Potzu, and the Yenshui rivers.

scholarly journals Bacterial enzymatic activity and bioavailability of heavy metals in sediments from Boa Viagem Beach (Guanabara Bay)

2003 ◽  
Vol 26 ◽  
pp. 60-68
Author(s):  
Mirian Crapez ◽  
José Antonio Baptista Neto ◽  
M. G. S. Bispo
Keyword(s):  
Heavy Metals ◽  
Organic Matter ◽  
Organic Carbon ◽  
Bacterial Count ◽  
Total Bacterial Count ◽  
Carbon Turnover ◽  
Guanabara Bay ◽  
Organic Matter Quality ◽  
Number Of Bacteria

This study focuses on the quality of the organic matter that reaches the sediment from Boa Viagem Beach and through the evaluation of the total bacterial count, the electron transport system activity (ETSA), the esterase activity (EST), as well as the protein and the organic matter contents. Seasonal variations of organic matter, protein content and the number of bacteria were particularly notable in the summer. ETSA reached a maximum of 7.48 µl O2 h-1 g-1 in the summer. EST activity presented a different pattern once it reached a maximum of 0.17 µg fluorescein h-1 g-1 in the winter. The temporal variation of ETSA and EST activity indicated that biopolymers predominated in the winter, and oligomers or monomers predominated in the summer. These results suggest that organic carbon turnover is more likely to be controlled by organic matter quality. The heavy metals concentrations, especially for Cu, Zn, Ni and Cr, indicated absence of the inhibition of dehydrogenase activity, and they are not bioavailable in the EC50 values

scholarly journals CARACTERÍSTICAS GEOQUÍMICAS DE LOS SEDIMENTOS SUPERFICIALES DE LA LAGUNA LA RESTINGA, ISLA DE MARGARITA, VENEZUELA.

2016 ◽  
Author(s):  
Juan Velásquez ◽  
Arístide Márquez ◽  
Ivis Fermín ◽  
Fabiola López ◽  
Deudedit Hernández ◽  
...  
Keyword(s):  
Organic Matter ◽  
Calcium Carbonate ◽  
Organic Carbon ◽  
Total Nitrogen ◽  
Total Phosphorus ◽  
Fine Particles ◽  
Sandy Loam ◽  
Aliphatic Hydrocarbons ◽  
Main Body ◽  
Total Organic Matter

This research aims to evaluate some chemical parameters of surface sediments of La Restinga coastal lagoon, located in Margarita Island, Nueva Esparta State, Venezuela. Using classical methodology for geochemical studies, grain size and texture of sediment percentage of organic carbon and total organic matter, as well as calcium carbonate were analyzed. Additionally, the concentrations of total nitrogen, total phosphorus and aliphatic hydrocarbons were determined. The results showed that in La Restinga lagoon sedimentary sandy texture dominate above sandy-loam and sandy-clay. The percentages of total organic carbon, total organic matter and calcium carbonate respectively varied as follows: 1.70-25.53%, 11.10-82.10% and 2.93-44.01%. Concentrations of 282.10-1571.80 mg kg-1 in total nitrogen, 419.50-2033.70 mg kg-1 in total phosphorus and 5.65-63.18 mg kg-1 for aliphatic hydrocarbons were determined. The total organic matter in the lagoon La Restinga is distributed based on the fine particles of sediment and the presence of mangroves, in turn calcium carbonate, was associated mainly to contributions from organisms with calcareous shell. The low values of the ratio NT/PT (under 5) suggest limitation of nitrogen in the ecosystem, and natural or anthropogenic enrichment of phosphorus in the sediment. The levels found of certain aliphatic hydrocarbons, are not considered as contamination levels as established by CARIPOL (1980), except in the eastern end of the main body of the lagoon. According to the points made in this study, we can infer that La Restinga Lagoon showed symptoms of degradation product of human intervention in the ecosystem.

scholarly journals Application of organomineral fertilizers sourced from filter cake and sewage sludge can affect nutrients and heavy metals in soil during early development of maize

2019 ◽  
pp. 863-873
Author(s):  
Mara Lúcia Martins Magela ◽  
Reginaldo de Camargo ◽  
Regina Maria Quintão Lana ◽  
Melissa Cristina de Carvalho Miranda
Keyword(s):  
Heavy Metals ◽  
Organic Matter ◽  
Organic Carbon ◽  
Early Development ◽  
Filter Cake ◽  
Soil Phosphorus ◽  
Block Design ◽  
Positive Control ◽  
Mineral Fertilization ◽  
Maize Crop

This study determined the changes in soil nutrients, organic carbon, organic matter and heavy metals during the early development stages of maize fertilized with different sources and doses. Also, this study confirmed that the used biosolid in the formulation of organomineral fertilizer makes greater efficacy than the effects promoted by mineral or filter cake organomineral fertilizers already used in agricultural. The experiment was done in a greenhouse at the Federal University of de Uberlândia - Campus Umuarama. The experimental design was randomized block design, as a 2 x 5 + 2 factorial, containing two sources of organomineral fertilizer consisting of organic residues (biosolid and filter cake), five doses of organomineral fertilizer (60, 80, 100, 120 and 140% of P2O5 recommendation for maize crop), a positive control with mineral fertilization (100%) and a negative one with no fertilization with four replications. The soil pH and contents of phosphorus, potassium, calcium, magnesium base saturation, base sum, micronutrients, organic carbon, organic matter and heavy metals were determined subsequently after plant removal, 65 days after sowing. The organomineral fertilizers based on biosolid and filter cake yielded increases in phosphorus, boron and manganese in the soil, especially the biosolid source. Regardless of the fertilizer organic matter source, soil phosphorus increased linearly with increasing doses of the sources. Doses equal or below the recommendation for maize (100% P2O5) were less effective in supplying potassium. The organomineral sources did not add heavy metals to the soil. Fertilizers based on biosolid can supply nutrients, such as phosphorus, boron and manganese at high doses, replacing mineral fertilization, while maintaining and improving soil fertility with no contamination by heavy metals.

Influence of Different Acid Treatments on the Radiocarbon Content Spectrum of Sedimentary Organic Matter Determined by RPO/Accelerator Mass Spectrometry

Radiocarbon ◽  
2018 ◽  
Vol 61 (2) ◽  
pp. 395-413 ◽  
Author(s):  
Rui Bao ◽  
Ann P McNichol ◽  
Jordon D Hemingway ◽  
Mary C Lardie Gaylord ◽  
Timothy I Eglinton
Keyword(s):  
Mass Spectrometry ◽  
Organic Matter ◽  
Organic Carbon ◽  
Acid Treatment ◽  
Inorganic Carbon ◽  
River Sediments ◽  
Labile Organic Carbon ◽  
Underlying Causes ◽  
High Carbonate ◽  
Acid Treatments

ABSTRACTIn practice, obtaining radiocarbon (14C) composition of organic matter (OM) in sediments requires first removing inorganic carbon (IC) by acid-treatment. Two common treatments are acid rinsing and fumigation. Resulting14C content obtained by different methods can differ, but underlying causes of these differences remain elusive. To assess the influence of different acid-treatments on14C content of sedimentary OM, we examine the variability in14C content for a range of marine and river sediments. By comparing results for unacidified and acidified sediments [HCl rinsing (RinseHCl) and HCl fumigation (FumeHCl)], we demonstrate that the two acid-treatments can affect14C content differentially. Our findings suggest that, for low-carbonate samples, RinseHClaffects the Fm values due to loss of young labile organic carbon (OC). FumeHClmakes the Fm values for labile OC decrease, leaving the residual OC older. High-carbonate samples can lose relatively old organic components during RinseHCl, causing the Fm values of remaining OC to increase. FumeHClcan remove thermally labile, usually young, OC and reduce the Fm values. We suggest three factors should be taken into account when using acid to remove carbonate from sediments: IC abundance, proportions of labile and refractory OC, and environmental matrix.

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