Constant current chronopotentiometric stripping characterisation of organic matter in seawater from the northern Adriatic, Croatia

2014 ◽  
Vol 11 (2) ◽  
pp. 158 ◽  
Author(s):  
Slađana Strmečki ◽  
Jelena Dautović ◽  
Marta Plavšić
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Seasonal Changes ◽  
Electrochemical Techniques ◽  
Organic Matter Content ◽  
Matter Content ◽  
Constant Current ◽  
Po River ◽  
Northern Adriatic ◽  
Catalytically Active

Environmental context We determined seasonal changes in the organic matter content of the northern Adriatic with newly applied electrochemical techniques able to measure catalytically active organics. The inflow of the Po River and its nutrient load are responsible for the observed changes in the type and concentrations of organic matter in the area. Abstract Catalytically active polysaccharides (Cat PSs) and nitrogen-containing polymeric organic material (N-POM) were determined in seawater from the northern Adriatic station ST101. Catalytically active organics were measured by applying electrochemical methods of adsorptive transfer chronopotentiometric stripping with medium exchange and chronopotentiometric stripping in unmodified seawater. Their concentrations were expressed in milligrams per cubic decimetre–3--> of equivalents of the model calibrating substances, polysaccharide xanthan and protein human serum albumin. The optimal electroanalytical conditions for determination of Cat PSs in seawater were evaluated and defined. Seasonal changes of Cat PSs and N-POM were observed during the period 2011–2013. The highest values were determined in the spring–summer period and the lowest in winter. Cat PSs and N-POM were present in both the dissolved and particulate organic carbon fractions. Cat PSs and N-POM showed a statistically significant positive correlation with the concentrations of surface-active substances. A weak but statistically significant correlation was found between Cat PSs and dissolved organic carbon concentrations. Copper complexing capacities in the period 2011–2013 were in the range of 41–130nmoldm–3.

scholarly journals Impacts of vinasse and methods of sugarcane harvesting on the availability of K and carbon stock of an Argisol

Revista CERES ◽  
2016 ◽  
Vol 63 (1) ◽  
pp. 95-102 ◽  
Author(s):  
Claudinei Alberto Cardin ◽  
Carlos Henrique dos Santos ◽  
Marcos Antonio Escarmínio
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Carbon Stock ◽  
Organic Matter Content ◽  
Matter Content ◽  
Total Carbon ◽  
Native Forest ◽  
Mean Values ◽  
Tropical Regions ◽  
Soil Carbon Stock

ABSTRACT Soils of tropical regions are more weathered and in need of conservation managements to maintain and improve the quality of its components. The objective of this study was to evaluate the availability of K, the organic matter content and the stock of total carbon of an Argisol after vinasse application and manual and mechanized harvesting of burnt and raw sugarcane, in western São Paulo.The data collection was done in the 2012/2013 harvest, in a bioenergy company in Presidente Prudente/SP. The research was arranged out following a split-plot scheme in a 5x5 factorial design, characterized by four management systems: without vinasse application and harvest without burning; with vinasse application and harvest without burning; with vinasse application and harvest after burning; without vinasse application and harvest after burning; plus native forest, and five soil sampling depths (0-10 10-20, 20-30, 30-40, 40-50 cm), with four replications. In each treatment, the K content in the soil and accumulated in the remaining dry biomass in the area, the levels of organic matter, organic carbon and soil carbon stock were determined. The mean values were compared by Tukey test. The vinasse application associated with the harvest without burning increased the K content in soil layers up to 40 cm deep. The managements without vinasse application and manual harvest after burning, and without vinasse application with mechanical harvesting without burning did not increase the levels of organic matter, organic carbon and stock of total soil organic carbon, while the vinasse application and harvest after burning and without burning increased the levels of these attributes in the depth of 0-10 cm.

EFFECT OF LONG-TERM PIG SLURRY AND SOLID CATTLE MANURE APPLICATION ON SOIL CHEMICAL AND BIOLOGICAL PROPERTIES

1989 ◽  
Vol 69 (1) ◽  
pp. 39-47 ◽  
Author(s):  
A. NDAYEGAMIYE ◽  
D. CÔTÉ
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Microbial Activity ◽  
Humic Acids ◽  
Organic Matter Content ◽  
Biological Properties ◽  
Matter Content ◽  
Cattle Manure ◽  
Pig Slurry

Chemical and biological properties were evaluated in 1987 on an acidic silty loam soil following a long-term field study established in 1978 and cultivated with silage corn. Treatments included a control, solid cattle manure (20, 40 and 60 Mg ha−1 FYM) and pig slurry (60, 120 m3 ha−1 SLU) applied every 2 yr and annually, respectively. No fertilizer was applied. The results of this study have shown that neither treatment significantly affected soil pH values, total-N contents and C:N ratios compared to the control. The cation exchange capacity (CEC) of the soil was significantly higher with FYM treatment than with control or SLU application. The highest rates of FYM and SLU have also increased (P < 0.05) soil organic carbon, microbial activity and potentially mineralizable nitrogen. The soil microflora populations (bacteria, fungi, actinomycetes, ammonifiers and nitrifiers) were greatly improved by both treatments. There were no significant differences in organic matter content or the relative amount of humic and fulvic acids between FYM and SLU plots. In spite of these results, FYM application (40 and 60 Mg ha−1) did affect more significantly the distribution of organic carbon in HA and the E4/E6 quotients than SLU additions. Humic acids extracted from SLU amended soils had a lower C content and lower E4/E6 ratios than humic acids from FYM soils. Long-term SLU application did not contribute to decreased organic matter content, CEC and humic acids yield, probably because of optimal organic residues returned to the soil by the corn crops. The FYM application generally improved soil chemical and biological properties. For a sustainable soil productivity, long-term SLU application should then be avoided in rotation in which small amounts of plant residues are returned, especially on soils with low organic matter contents. Key words: Organic matter, microbial activity, nitrogen mineralization potential, CEC, solid cattle manure, pig slurry

scholarly journals Organic carbon determination in histosols and soil horizons with high organic matter content from Brazil

2006 ◽  
Vol 63 (2) ◽  
pp. 187-193 ◽  
Author(s):  
Marcos Gervasio Pereira ◽  
Gustavo Souza Valladares ◽  
Lúcia Helena Cunha dos Anjos ◽  
Vinícius de Melo Benites ◽  
Ademar Espíndula Jr. ◽  
...  
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Organic Matter Content ◽  
Analysis Data ◽  
Matter Content ◽  
Organic Soils ◽  
Organic Carbon Content ◽  
Muffle Furnace ◽  
Soil Taxonomy ◽  
High Organic Carbon Content

Soil taxonomy systems distinguish mineral soils from organic soils based on the amount of soil organic carbon. Procedures adopted in soil surveys for organic carbon measurement are therefore of major importance to classify the soils, and to correlate their properties with data from other studies. To evaluate different methods for measuring organic carbon and organic matter content in Histosols and soils with histic horizons, from different regions of Brazil, 53 soil samples were comparatively analyzed by the methods of Walkley & Black (modified), Embrapa, Yeomans & Bremner, modified Yeomans & Bremner, muffle furnace, and CHN. The modified Walkley & Black (C-W & B md) and the combustion of organic matter in the muffle furnace (OM-Muffle) were the most suitable for the samples with high organic carbon content. Based on regression analysis data, the OM-muffle may be estimated from C-W & B md by applying a factor that ranges from 2.00 to 2.19 with 95% of probability. The factor 2.10, the average value, is suggested to convert results obtained by these methods.

scholarly journals The color of refractory organic carbon

2018 ◽  
Vol 189 (2) ◽  
pp. 9 ◽  
Author(s):  
Maxime Debret ◽  
Yoann Copard ◽  
Antonin Van Exem ◽  
Geneviève Bessereau ◽  
Frank Haeseler ◽  
...  
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Carbon Content ◽  
Anthropogenic Activities ◽  
Organic Matter Content ◽  
Matter Content ◽  
Mineral Matter ◽  
Organic Carbon Content ◽  
Fast Method ◽  
Wide Range

Organic matter studies find an echo within different topics such as biogeochemical cycles, processes occurring in continental surfaces, anthropogenic activities, climate science, earth and planetary sciences, etc. Today’s challenges include finding and developing the most appropriate method(s) supporting the differentiation and characterisation of various types of recalcitrant organic matter in modern environments. In this study, we focus on combustion residues and coals as these two types of organic matter contain a significant amount of so-called recalcitrant organic carbon (black carbon and fossil organic carbon). Both these materials are ubiquitous, broadly stem from the same living organisms and have similar polyaromatic structures. In this respect, we tested a spectrophotometry method, classically used for sedimentology, as a very fast method for preliminary investigations. Analyses were performed with a wide range of standards and referenced samples. The results discriminate three different spectral signatures related to the degree of transformation of organic matter related to the degree of aromaticity (i.e. carbonisation). Using calibration curves, total organic carbon content can be estimated in experimental mixes with mineral matter and in a real context using subsurface sample (Gironville 101 borehole, Paris Basin, France). This method has particularly high sensitivity to very low organic matter content and is shown to be promising for a rapid evaluation of the organic carbon content.

Assessing the impact of dissolved organic carbon changes on disinfectant stability in a distribution system

2002 ◽  
Vol 2 (3) ◽  
pp. 251-257
Author(s):  
C. Campos ◽  
Ph. Harmant
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Distribution System ◽  
Distribution Systems ◽  
Organic Matter Content ◽  
Matter Content ◽  
Quality Model ◽  
Organic Carbon Concentration ◽  
Concentration Changes ◽  
The Impact

Maintaining disinfectant residuals throughout the entire water distribution system is considered an efficient strategy to guarantee the biological stability of drinking water as it flows from the plant to the customer tap. Dosed at the plant, the disinfectant disappears in the distribution system due to reactions with both water and pipe constituents. Among them, certain fractions of the organic matter content are directly responsible for the loss of disinfectant. This study presents an example of the impact of the organic matter UV absorbance on free chlorine decay for a surface water. In addition, this study illustrates the use of laboratory experiments together with a water quality model as a valuable tool to predict the impact of organic carbon concentration changes on chlorine residuals in interconnected distribution systems.

scholarly journals EVALUATION OF SUBSTRATES MINERALIZATION BY C-CO2 FLUX UNDER NITROGEN FERTILIZATION

2019 ◽  
Vol 49 (1 y 2) ◽  
pp. 19-28
Author(s):  
Víctor Manuel Montoya-Jasso ◽  
Gerardo Sergio Benedicto Valdés ◽  
Víctor Manuel Ordaz Chaparro ◽  
Alejandrina Ruiz-Bello ◽  
Jesús Manuel Arreola Tostado ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Organic Matter ◽  
Organic Carbon ◽  
Nitrogen Fertilization ◽  
Organic Matter Content ◽  
Co2 Flux ◽  
Matter Content ◽  
Porous Space ◽  
Gas Analyzer ◽  
Mineral Mixture

The objective was to evaluate the mineralization of two mixtures of substrates with different nitrogen content, moisture, compost and mineral mixture based on zeolite and dolomite. The measured parameters were pH (extract 1:2), electrical conductivity (extract 1:5) by conductimeter; content of organic matter by ignition; organic carbon based on the results of organic matter using the Douglas factor= 0.5; and nitrogen per micro Kjeldahl. The flow of CO2 was measured with the IRGA gas analyzer. For both moisture content, the compost-free substrates had a higher C/N ratio. Compost substrates, because of their high mineralization, were appropriate with advantages to the supply of nitrogen. Substrates with compost and 15% moisture released higher CO2 by presenting more easily degradable compounds. Mineralization rates on substrates were higher with 15% humidity due to increased porous space occupied by gases, in addition, the supply of 50% of nitrogen had a low immobilization due to the lower organic matter content and the 40 cm3 L-1 mineral mixture content changed the dilution of carbon to be metabolized by microorganisms. The rate of mineralization was affected by the use of minerals, the quality and the subtrate origin

Water repellency of post-boggy soils with a various content of organic matter

Biologia ◽  
2009 ◽  
Vol 64 (3) ◽  
Author(s):  
Andrzej Lachacz ◽  
Monika Nitkiewicz ◽  
Barbara Kalisz
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Significant Positive Correlation ◽  
C:N Ratio ◽  
Organic Matter Content ◽  
Water Repellency ◽  
Matter Content ◽  
Organic Soils ◽  
Mineral Matter ◽  
Positive Correlation

AbstractThe objective of this study was to estimate the water repellency of post-boggy soils in north-eastern Poland. Potential water repellency was determined based on the water drop penetration time (WDPT) test and the molarity of an ethanol droplet (MED) test. A total of 276 soil samples with a varied organic carbon (OC) content, ranging from trace amounts in sandy subsoils to 44.4% in organic soils, were analyzed. The investigated material represents peat-muck soils (Eutri-Sapric Histsols) and muck-like soils (Arenic Gleysols, Areni-Humic Gleysols, Gleyic Arenosols). The mineral matter of the analyzed soils comprised loose sand. The obtained results indicate that peat soil formations are marked by higher potential water repellency than muck soil formations. The highest WDPT values (16 390 s) were reported in respect of an alder peat sample with 41.9% OC content, collected at a depth of 55–60 cm. In the group of muck soils, a sample with 36.7% OC content, collected at a depth of 15–20 cm, was marked by the highest water repellency (WDPT 10 492 s). The water repellency of the studied soils is dependent on organic matter content, and it is manifested only when organic matter content is higher than 20%. Soils with OC content of up to 12% show low water repellency or are hydrophilic. Organic soil formations (>12% OC) are characterized by a varied degree of water repellency, but WDPT values in excess of 2000 s are reported only in respect of soils containing more than 35% OC. A significant positive correlation between the content of organic matter, organic carbon, total nitrogen and water repellency was observed in the entire studied population (n = 276). A significant positive correlation was also found between WDPT values and the C:N ratio, while a significant negative correlation was reported in respect of $$ pH_{H_2 O} $$.

scholarly journals TOTAL AND PARTICULATE CONTENTS AND VERTICAL STRATIFICATION OF ORGANIC CARBON IN AGROFORESTRY SYSTEM IN CAATINGA

2021 ◽  
Vol 34 (2) ◽  
pp. 443-451
Author(s):  
BRUNA DE FREITAS IWATA ◽  
MARIA LETÍCIA STEFANY MONTEIRO BRANDÃO ◽  
REGIS DOS SANTOS BRAZ ◽  
LUIZ FERNANDO CARVALHO LEITE ◽  
MIRIAN CRISTINA GOMES COSTA
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Particulate Organic Carbon ◽  
Organic Matter Content ◽  
Gliricidia Sepium ◽  
Agroforestry System ◽  
Matter Content ◽  
Vertical Stratification ◽  
Sensitivity Index ◽  
Organic Residues

ABSTRACT The objective of this work was to evaluate the variation in total and particulate organic carbon contents, carbon vertical stratification, and sensitivity index of organic matter fractions in soils with organic residues arranged in alleys in an agroforestry system, with and without use of fire, in the Caatinga biome, in Brazil. The experiment was conducted in a split-plot arrangement with four replications, with the factor fire in the plots, and the factor organic residues in the subplots. The organic residues used consisted of Gliricidia sepium plants; G. sepium plants and carnauba processing residue; G. sepium plants and bio-compost; and G. sepium plants, carnauba processing residue, and bio-compost, which were evaluated in three soil layers. The alleys with carnauba processing residue, G. sepium plants, and bio-compost presented a better maintenance of particulate, and mineral-associated organic carbon contents. Thus, the agroforestry management in alleys using these three residues was efficient for the maintenance of labile and recalcitrant organic matter compartments. Particulate organic carbon was more sensitive to changes in soil management than total organic matter content, in all alleys, presenting higher sensitivity indexes.

Role of Humified Organic Matter in Herbicide Adsorption

1989 ◽  
Vol 3 (1) ◽  
pp. 190-197 ◽  
Author(s):  
Patrick J. Shea
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Partition Coefficient ◽  
Organic Matter Content ◽  
Clay Content ◽  
Aqueous Solubility ◽  
Structural Diversity ◽  
Polar Compounds ◽  
Matter Content ◽  
Organic Carbon Content

Organic matter is the soil constituent most often associated with herbicide adsorption. Structural diversity makes humified organic material an ideal substrate for the adsorption of many pesticides, but variability in composition and distribution in situ complicates interpretation of its quantitative effect on adsorption. Variability in the adsorption distribution coefficient (KD) of a herbicide among soils often is due to differences in organic matter content and can be reduced by adjusting KDfor soil organic carbon content and computing the organic carbon partition coefficient (Koc). Koccan be estimated from the octanol-water partition coefficient (Kow) of organic compounds, but the correlation weakens as compound polarity increases. Kocalso can be correlated with aqueous solubility if a correction is made for the melting point of compounds that are solids at 25 C. Relative adsorption can be estimated from parachor and molecular connectivity indices; but corrections are needed for polar compounds, and correlations with KDor Kochave been variable. Such predictive methods may be useful for broad classification purposes, but accurate extrapolation generally requires site-specific adsorption measurements. Empirical models which accommodate the multiple regression of organic matter content and other soil properties such as clay content, pH, and cation exchange capacity on herbicide adsorption can increase accuracy, but interpretation may be restricted to a small number of sites.

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