scholarly journals Belowground in situ redox dynamics and methanogenesis recovery in a degraded fen during dry-wet cycles and flooding

2012 ◽  
Vol 9 (8) ◽  
pp. 11655-11704 ◽  
Author(s):  
C. Estop-Aragonés ◽  
K.-H. Knorr ◽  
C. Blodau
Keyword(s):  
Organic Matter ◽  
Water Table ◽  
Methane Production ◽  
Solid Phase ◽  
Electron Flow ◽  
Organic Matter Content ◽  
Matter Content ◽  
Electron Acceptors ◽  
Oxygen Penetration ◽  
Ch4 Production

Abstract. Climate change induced drying and flooding may alter the redox conditions of organic matter decomposition in peat soils. The seasonal and intermittent changes in pore water solutes (NO3−, Fe2+, SO42−, H2S, acetate) and dissolved soil gases (CO2, O2, CH4, H2) under natural water table fluctuations were compared to the response under a reinforced drying and flooding in fen peats. Oxygen penetration during dryings led to CO2 and CH4 degassing and to a regeneration of dissolved electron acceptors (NO3−, Fe3+ and SO42−). Drying intensity controlled the extent of the electron acceptor regeneration. Iron was rapidly reduced and sulfate pools ~ 1 mmol L−1 depleted upon rewetting and CH4 did not substantially accumulate until sulfate levels declined to ~ 100 μmoll−1. The post-rewetting recovery of soil methane concentrations to levels ~ 80 μmoll−1 needed 40–50 days after natural drought. This recovery was prolonged after experimentally reinforced drought. A greater regeneration of electron acceptors during drying was not related to prolonged methanogenesis suppression after rewetting. Peat compaction, solid phase content of reactive iron and total reduced inorganic sulfur and organic matter content controlled oxygen penetration, the regeneration of electron acceptors and the recovery of CH4 production, respectively. Methane production was maintained despite moderate water table decline of 20 cm in denser peats. Flooding led to accumulation of acetate and H2, promoted CH4 production and strengthened the co-occurrence of iron and sulfate reduction and methanogenesis. Mass balances during drying and flooding indicated that an important fraction of the electron flow must have been used for the generation and consumption of electron acceptors in the solid phase or other mechanisms. In contrast to flooding, dry-wet cycles negatively affect methane production on a seasonal scale but this impact might strongly depend on drying intensity and on the peat matrix, whose structure and physical properties influence moisture content.

scholarly journals Belowground in situ redox dynamics and methanogenesis recovery in a degraded fen during dry-wet cycles and flooding

2013 ◽  
Vol 10 (1) ◽  
pp. 421-436 ◽  
Author(s):  
C. Estop-Aragonés ◽  
K.-H. Knorr ◽  
C. Blodau
Keyword(s):  
Organic Matter ◽  
Water Table ◽  
Methane Production ◽  
Solid Phase ◽  
Electron Flow ◽  
Organic Matter Content ◽  
Matter Content ◽  
Electron Acceptors ◽  
Oxygen Penetration ◽  
Ch4 Production

Abstract. Climate change induced drying and flooding may alter the redox conditions of organic matter decomposition in peat soils. The seasonal and intermittent changes in pore water solutes (NO3−, Fe2+, SO42−, H2S, acetate) and dissolved soil gases (CO2, O2, CH4, H2) under natural water table fluctuations were compared to the response under a reinforced drying and flooding in fen peats. Oxygen penetration during dryings led to CO2 and CH4 degassing and to a regeneration of dissolved electron acceptors (NO3−, Fe3+ and SO42−). Drying intensity controlled the extent of the electron acceptor regeneration. Iron was rapidly reduced and sulfate pools ~ 1 mM depleted upon rewetting and CH4 did not substantially accumulate until sulfate levels declined to ~ 100 μmol L−1. The post-rewetting recovery of soil methane concentrations to levels ~ 80 μmol L−1 needed 40–50 days after natural drought. This recovery was prolonged after experimentally reinforced drought. A greater regeneration of electron acceptors during drying was not related to prolonged methanogenesis suppression after rewetting. Peat compaction, solid phase content of reactive iron and total reduced inorganic sulfur and organic matter content controlled oxygen penetration, the regeneration of electron acceptors and the recovery of CH4 production, respectively. Methane production was maintained despite moderate water table decline of 20 cm in denser peats. Flooding led to accumulation of acetate and H2, promoted CH4 production and strengthened the co-occurrence of iron and sulfate reduction and methanogenesis. Mass balances during drying and flooding indicated that an important fraction of the electron flow must have been used for the generation and consumption of electron acceptors in the solid phase or other mechanisms. In contrast to flooding, dry-wet cycles negatively affect methane production on a seasonal scale, but this impact might strongly depend on drying intensity and on the peat matrix, of which structure and physical properties influence moisture content.

scholarly journals Examination of zinc adsorption capacity of soils treated with different pyrolysis products

2014 ◽  
Vol 6 (1) ◽  
pp. 33-38
Author(s):  
Gabriella Rétháti ◽  
Adrienn Vejzer ◽  
Barbara Simon ◽  
Ramadan Benjared ◽  
György Füleky
Keyword(s):  
Organic Matter ◽  
Adsorption Capacity ◽  
Solid Phase ◽  
Organic Matter Content ◽  
Pyrolysis Product ◽  
Matter Content ◽  
Pyrolysis Products ◽  
Bone Ash ◽  
Original Product ◽  
Zinc Adsorption

Abstract Organic matter input into soils is essential regarding agricultural, environmental and soil science aspects as well. However, the application of the pyrolysed forms of biochars and materials with different organic matter content gained more attention in order to decrease the emission of the green house gases (CO2, N2O) from the soil. During pyrolysis, the materials containing high organic matter (biomass-originated organic matter) are heated in oxygen-free (or limited amount of oxygen) environment. As a result, the solid phase, which remains after eliminating the gases and liquid phase, is more stable compared to the original product, it cannot be mineralized easily in the soil and its utilization is more beneficial in terms of climatic aspects. Furthermore, it can improve soil structure and it can retain soil moisture and cations in the topsoil for long periods of time, which is very important for plants. In our experiment, the effects of biochar and bone char were examined on soils by zinc adsorption experiments. Based on our experiments, we concluded that the pyrolysis products can have significant Zn adsorption capacity compared to the soil. Bone ash can adsorb more Zn than the charcoal product. The Zn adsorption capacity of soils treated by pyrolysis products can be described by Langmuir adsorption isotherms. However, based on the amount of pyrolysis products, one or two term Langmuir isotherm fits well on the experiment data, which depends on the time the pyrolysis product has spent in the soil.

Effect of diet and probiotic addition on chemical composition of free or particle-associated bacterial populations of the rumen

1998 ◽  
Vol 78 (1) ◽  
pp. 115-120 ◽  
Author(s):  
J. Chiquette ◽  
C. Benchaar
Keyword(s):  
Amino Acids ◽  
Organic Matter ◽  
Amino Acid ◽  
Chemical Composition ◽  
Volatile Fatty Acids ◽  
Solid Phase ◽  
Organic Matter Content ◽  
Latin Square ◽  
Matter Content ◽  
Bacterial Populations

Eight dairy heifers (297 ± 11 kg) fitted with a ruminal cannula were used in this study. The following diets were fed in a replicated, concurrently run 4 × 4 Latin square design: 1) 80% chopped timothy hay + 20% rolled barley (HF); 2) HF + 10 g head d−1 of a mixture of Saccharomyces cerevisiae and Aspergillus oryzae (HF + SA); 3) 50% chopped timothy hay + 47.6% rolled barley and 2.4% soya supplement (HC); 4) HC + SA. Feed was offered every 2 h. A sample of whole rumen contents (liquid and solid) was collected 1 h after the 07:00 h feeding to isolate the bacteria associated with the liquid phase (BAL) and the bacteria adherent to the solid phase (BAS). Organic matter (OM) content of BAS was greater (P ≤ 0.0001) than that of BAL, independently of the type of diet fed and of the presence or absence of the pro-biotic mixture. Oppositely, total nitrogen content (N), expressed as g 100 g−1 OM, was greater (P ≤ 0.0001) in the BAL fraction than in the BAS fraction, the difference in N between the two bacterial fractions being more pronounced with the HF diet (P ≤ 0.05). Organic matter content in both bacterial fractions was greater (P ≤ 0.05) when heifers were fed the HC diet. Addition of probiotic had no effect on OM or N content of each bacterial fraction. Significant differences between amino acid composition of BAL and BAS were observed for 10 out of 16 amino acids studied. For most amino acids, differences in content observed between BAL and BAS were maintained independently of the probiotic supplementation whereas diet affected the relative composition of the bacterial fractions for five amino acids. Finally, addition of probiotics did not affect molar proportions of ruminal volatile fatty acids, which were affected by the diet. Key words: Rumen bacteria, chemical composition, probiotic, amino acid

Free aluminum and aluminum complexation capacity of natural organic-matter in acidic forest soil solutions from Canterbury, New Zealand

Soil Research ◽  
1995 ◽  
Vol 33 (4) ◽  
pp. 611 ◽  
Author(s):  
HKJ Powell ◽  
DJ Hawke
Keyword(s):  
Organic Matter ◽  
Fulvic Acid ◽  
Soil Solution ◽  
Solid Phase ◽  
Ph Dependence ◽  
Organic Matter Content ◽  
Inverse Correlation ◽  
Matter Content ◽  
Complexation Capacity ◽  
Organic Horizons

Measurement of soil solution Al complexation capacity (Al-CC) at pH 4 . 7 by using a simple colorimetric flow injection analysis technique is described. Forest soils from four sites (Canterbury, N.Z.) of contrasting rainfall (from 655 mm to about 3000 mm) were examined. Results showed a strong inverse correlation (r2 = 0.992) between pH and log(soil solution Al-CC) in high-organic surface horizons, indicating that high rainfall generates both acidity and Al complexing ligands. Soil Al-CC (�mol Al kg-1 dry soil) was highest (199 �mol kg-1) in the Ca horizon from the wettest site, and lowest (2.2 � mol kg-1) in the B horizon of one of the intermediate rainfall sites. Soil solution Al-CC was proportional (r2 = 0.94) to the organic matter content of all horizons, as estimated by absorbance at 250 nm. The slope of the regression against A250, expressed as fulvic acid equivalent, gave a higher Al-CC (1360 � 210 mmol kg-1) than measured for soil fulvic acid alone (550 mmol kg-1), indicating a contribution from non-absorbing complexants. The pH dependence of log(free [Al]) (slope -0.38 � 0.17) implicates colloidal and/or solid phase organics in the control of soluble Al in organic horizons.

HEAVY METAL SPECIATION IN BOTTOM SEDIMENTS OF THE VYSHNEVOLOTSKY RESERVOIR

2018 ◽  
pp. 46-54
Author(s):  
O. A. Lipatnikova
Keyword(s):  
Heavy Metal ◽  
Organic Matter ◽  
Bottom Sediments ◽  
Metal Speciation ◽  
Organic Matter Content ◽  
Water Reservoir ◽  
Matter Content ◽  
Heavy Metal Speciation ◽  
Mobile Forms ◽  
Manganese Hydroxides

The study of heavy metal speciation in bottom sediments of the Vyshnevolotsky water reservoir is presented in this paper. Sequential selective procedure was used to determine the heavy metal speciation in bottom sediments and thermodynamic calculation — to determine ones in interstitial water. It has been shown that Mn are mainly presented in exchangeable and carbonate forms; for Fe, Zn, Pb и Co the forms are related to iron and manganese hydroxides is played an important role; and Cu and Ni are mainly associated with organic matter. In interstitial waters the main forms of heavy metal speciation are free ions for Zn, Ni, Co and Cd, carbonate complexes for Pb, fulvate complexes for Cu. Effects of particle size and organic matter content in sediments on distribution of mobile and potentially mobile forms of toxic elements have been revealed.

Physico-Chemical Properties of Soil Collected from Chandrabhaga River in Kalmeshwar, Nagpur, Maharashtra

2020 ◽  
Vol 07 (02) ◽  
pp. 1-3
Author(s):  
Amita M Watkar ◽  
Keyword(s):  
Organic Matter ◽  
Soil Quality ◽  
Agricultural Land ◽  
Organic Matter Content ◽  
Chemical Properties ◽  
Matter Content ◽  
Soil Attributes ◽  
Essential Components ◽  
Agricultural Land Management ◽  
Physical And Chemical

Soil, itself means Soul of Infinite Life. Soil is the naturally occurring unconsolidated or loose covering on the earth’s surface. Physical properties depend upon the amount, size, shape, arrangement, and mineral composition of soil particles. It also depends on the organic matter content and pore spaces. Chemical properties depend on the Inorganic and organic matter present in the soil. Soils are the essential components of the environment and foundation resources for nearly all types of land use, besides being the most important component of sustainable agriculture. Therefore, assessment of soil quality and its direction of change with time is an ideal and primary indicator of sustainable agricultural land management. Soil quality indicators refer to measurable soil attributes that influence the capacity of a soil to function, within the limits imposed by the ecosystem, to preserve biological productivity and environmental quality and promote plant, animal and human health. The present study is to assess these soil attributes such as physical and chemical properties season-wise.

scholarly journals Soil nitrogen supply of peat grasslands estimated by degree days and soil organic matter content

2020 ◽  
Vol 117 (3) ◽  
pp. 351-365
Author(s):  
J. Pijlman ◽  
G. Holshof ◽  
W. van den Berg ◽  
G. H. Ros ◽  
J. W. Erisman ◽  
...  
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Soil Nitrogen ◽  
Organic Matter Content ◽  
Matter Content ◽  
Nitrogen Supply ◽  
Degree Days ◽  
Soil Organic Matter Content ◽  
Soil Nitrogen Supply

scholarly journals Effect of Clay, Soil Organic Matter, and Soil pH on Initial and Residual Weed Control with Flumioxazin

Agronomy ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1326
Author(s):  
Calvin F. Glaspie ◽  
Eric A. L. Jones ◽  
Donald Penner ◽  
John A. Pawlak ◽  
Wesley J. Everman
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Weed Control ◽  
Soil Ph ◽  
Organic Matter Content ◽  
Amaranthus Retroflexus ◽  
Matter Content ◽  
Weed Species ◽  
Soil Organic Matter Content ◽  
Field Soils

Greenhouse studies were conducted to evaluate the effects of soil organic matter content and soil pH on initial and residual weed control with flumioxazin by planting selected weed species in various lab-made and field soils. Initial control was determined by planting weed seeds into various lab-made and field soils treated with flumioxazin (71 g ha−1). Seeds of Echinochloa crus-galli (barnyard grass), Setaria faberi (giant foxtail), Amaranthus retroflexus (redroot pigweed), and Abutilon theophrasti (velvetleaf) were incorporated into the top 1.3 cm of each soil at a density of 100 seeds per pot, respectively. Emerged plants were counted and removed in both treated and non-treated pots two weeks after planting and each following week for six weeks. Flumioxazin control was evaluated by calculating percent emergence of weeds in treated soils compared to the emergence of weeds in non-treated soils. Clay content was not found to affect initial flumioxazin control of any tested weed species. Control of A. theophrasti, E. crus-galli, and S. faberi was reduced as soil organic matter content increased. The control of A. retroflexus was not affected by organic matter. Soil pH below 6 reduced flumioxazin control of A. theophrasti, and S. faberi but did not affect the control of A. retroflexus and E. crus-galli. Flumioxazin residual control was determined by planting selected weed species in various lab-made and field soils 0, 2, 4, 6, and 8 weeks after treatment. Eight weeks after treatment, flumioxazin gave 0% control of A. theophrasti and S. faberi in all soils tested. Control of A. retroflexus and Chenopodium album (common lambsquarters) was 100% for the duration of the experiment, except when soil organic matter content was greater than 3% or the soil pH 7. Eight weeks after treatment, 0% control was only observed for common A. retroflexus and C. album in organic soil (soil organic matter > 80%) or when soil pH was above 7. Control of A. theophrasti and S. faberi decreased as soil organic matter content and soil pH increased. Similar results were observed when comparing lab-made soils to field soils; however, differences in control were observed between lab-made organic matter soils and field organic matter soils. Results indicate that flumioxazin can provide control ranging from 75–100% for two to six weeks on common weed species.

Sign in / Sign up

Export Citation Format

Share Document