Is Oxygenation Related to the Decomposition of Organic Matter in Cryoconite Holes?

AbstractCryoconite is a sediment occurring on glacier surfaces worldwide which reduces ice albedo and concentrates glacier surface meltwater into small reservoirs called cryoconite holes. It consists of mineral and biogenic matter, including active microorganisms. This study presents an experimental insight into the influence of sediment oxygenation on the cryoconite ability to produce and decomposition of organic matter. Samples were collected from five glaciers in the Arctic and the European mainland. Cryoconite from three glaciers was incubated in stagnant and mechanically mixed conditions to imitate inter-hole water–sediment mixing by meltwater occurring on glaciers in Northern Hemisphere, and its effect on oxygen profiles and organic matter content. Moreover, we investigated short-term changes of oxygen conditions in cryoconite from four glaciers in illuminated and dark conditions. An anaerobic zone was present or approaching zero oxygen in all illuminated cryoconite samples, varying in depth depending on the origin of cryoconite: from 1500 µm from Steindalsbreen (Scandinavian Peninsula) and Forni Glacier (The Alps) to 3100 µm from Russell Glacier and Longyearbreen (Arctic) after incubation. Organic matter content varied between glaciers from 6.11% on Longyearbreen to 16.36% on Russell Glacier. The mixed sediment from the Forni Glacier had less organic matter than stagnant, the sediment from Longyearbreen followed this trend, but the difference was not statistically significant, while the sediment from Ebenferner did not differ between groups. Our results have implications for the understanding of biogeochemical processes on glacier surfaces, the adaptation of organisms to changing physical conditions due to abrupt sediment mixing, but also on the estimation of productivity of supraglacial systems.

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Soil organic carbon fractions in a Vertisol under irrigated cotton production as affected by burning and incorporating cotton stubble

Soil Research ◽

10.1071/s97117 ◽

1998 ◽

Vol 36 (4) ◽

pp. 655 ◽

Cited By ~ 31

Author(s):

A. Conteh ◽

G. J. Blair ◽

I. J. Rochester

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Organic Matter Content ◽

Matter Content ◽

Total Carbon ◽

Cotton Production ◽

Labile Carbon ◽

Total N ◽

The Difference ◽

Organic Matter Fractions

The contribution of cotton stubble to the soil organic matter content of Vertisols under cotton production is not well understood. A 3-year experiment was conducted at the Australian Cotton Research Institute to study the effects of burning and incorporating cotton stubble on the recovery of fertiliser nitrogen (N), lint yield, and organic matter levels. This study reports on the changes in soil organic matter fractions as affected by burning and incorporating cotton stubble into the soil. Soil samples collected at the start and end of the 3-year experiment were analysed for total carbon (CT), total N (NT), and δ13C (a measure of 13C/12C isotopic ratios). Labile carbon (CL) was determined by ease of oxidation and non-labile carbon (CNL) was calculated as the difference between CT and CL. Based on the changes in CT, CL, and CNL, a carbon management index (CMI) was calculated. Further analyses were made for total polysaccharides (PT), labile polysaccharides (PL), and light fraction C (LF-C). Stubble management did not significantly affect the NT content of the soil. After 3 years, the stubble-incorporated plots had a significantly higher content of CT, CL, and polysaccharides. Incorporation of stubble into the soil increased the CMI by 41%, whereas burning decreased the CMI by 6%. The amount of LF-C obtained after 3 years in the stubble-incorporated soil was almost double that obtained in the stubble-burnt soil. It was concluded that for sustainable management of soil organic matter in the Vertisols used for cotton production, stubble produced in the system should be incorporated instead of burnt.

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A source of error in the estimation of the organic matter content of samples containing calcium carbonate

The Journal of Agricultural Science ◽

10.1017/s0021859600025922 ◽

1972 ◽

Vol 79 (3) ◽

pp. 541-542 ◽

Cited By ~ 1

Author(s):

F. D. DeB. Hovell ◽

E. R. Ørskov

Keyword(s):

Organic Matter ◽

Calcium Carbonate ◽

Volatile Fatty Acids ◽

Organic Matter Content ◽

Matter Content ◽

Carbonate Content ◽

Apparent Digestibility ◽

High Calcium ◽

The Difference

The conventional method for the determination of the organic matter content of diets and faeces is by ashing the sample at 550 °C (A.O.A.C, 1965)Organic matter (O.M.) = dry matter (D.M.)–ash.If the sample contains calcium carbonate, then some of this carbonate will be converted to oxide (Vogel, 1951) and the weight of carbon dioxide evolved will be calculated as organic matter. The amount of carbonate converted will be dependent upon the temperature at which the sample is ashed and the duration of the ashing process. We have found (Ørskov, Hovell & Allen, 1966; Hovell & Greenhalgh, 1972) that when calcium salts of volatile fatty acids are included in diets given to sheep, most of the calcium is excreted in the faeces as carbonate, and since apparent digestibility is the difference between the amounts of nutrient ingested and excreted, the estimation of the apparent digestibility of organic matter will be in error if no correction is made for the high calcium carbonate content of the faeces. For example, a diet which contained 9·2% of calcium acetate had a true organic matterapparent digestibility of 86·8%. Had no correction been made this would have been estimated as 84·9%.

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Effect of Growing Groundcover Plants in a Vineyard on Dissipation of Two Neonicotinoid Insecticides

Sustainability ◽

10.3390/su11030798 ◽

2019 ◽

Vol 11 (3) ◽

pp. 798

Author(s):

Jui-Hung Yen ◽

Chien-Sen Liao ◽

Ya-Wen Kuo ◽

Wen-Ching Chen ◽

Wan-Ting Huang

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Metabolic Rate ◽

Organic Matter Content ◽

Matter Content ◽

High Metabolic Rate ◽

Soil Organic Matter Content ◽

Arachis Pintoi ◽

Residue Concentration ◽

The Difference

This study investigated the difference in neonicotinoids dissipation in a grape vineyard by planting different groundcovers plants, including a control bare field (CF), Arachis pintoi Krap. and Greg. (peanut field (PF)) and Clinopodium brownei (Sw.) Kuntze (mint field (MF)). After one day of pesticide spraying, the highest dinotefuran residue concentration was in 0- to 15-cm soil in the CF (0.161 mg/kg), but 30- to 45-cm and 15- to 30-cm soil in the MF and PF, respectively (0.307 and 0.033 mg/kg). Also, after four days, the highest imidacloprid residue concentration was in 0- to 15-cm soil in the CF. Imidacloprid was not retained in the 30- to 45-cm soils in the PF, but in the MF, a 0.015- and 0.011-mg/kg residue was detected in 30- to 45-cm soil in the second and third soil samplings, indicating a different distribution with different groundcover plants. The dinotefuran absorption ability was greater with A. pintoi than C. brownei, and the imidacloprid absorption ability was greater with C. brownei. Our results suggest that groundcover plants affect the dissipation of neonicotinoids differently, while A. pintoi has a high metabolic rate toward the two neonicotinoids and can increase the soil organic matter content, which is a preferable choice for a groundcover.

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The Dynamics of the Litter and Soil Organic Matter in Four Densities of Hybrid Larch Plantations

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.524-527.2152 ◽

2012 ◽

Vol 524-527 ◽

pp. 2152-2155

Author(s):

Shu Li Wang ◽

Xue Mei Li ◽

Wei Bin Yuan

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Soil Layer ◽

Organic Matter Content ◽

Matter Content ◽

Hybrid Larch ◽

Soil Organic Matter Content ◽

Larch Plantation ◽

The Difference ◽

Forest Farm

The dynamics of the litter and soil organic matter content of four densities (A: 2500/hm2，B:3300/hm2，C:4400/hm2，D:6600/hm2) of hybrid Larch plantations were studied in Jiangshanjiao forest farm of Heilongjiang province of China. (1) The annual litter stock under the hybrid Larch plantation was 4634.6 ~ 5453.4 kg/hm2, and the decreased order of the annual litter stock was under density of 4400, 3300 2500and 6600 trees per hectare. The decrease order of the litter stock no matter undecomposition and decomposition litter was under density of 3300, 4400, 2500 and 6600 trees per hectare, and the rate of the undecomposition litter stock to total litter stock was bigger than 50 %. (2) The seasonal dynamic of the soil organic matter under different densities of plantations basically had the same principle. In 0~10 cm soil layer, the soil organic matter was higher in June and August, was lower in May and July, and was flat or increased slightly in September, but was decreased in September under the plantations with density 4400 and 3300 trees per hectare. The soil organic matter in 10~20 cm and 20~40 cm layer had the same change principle, but the change range was flat and smooth. For the same density of plantation, the difference of the organic matter in the same soil layer between the different months was significantly (P < 0.05). (3) The difference of the soil organic matter content in the same soil layer under different densities of hybrid Larch plantation was significantly, and the decreased order of the soil organic matter in average was under density 4400, 3300, 6600 and 2500 trees per hectare. The results would provide the theories basis for manage the hybrid Larch plantations.

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Calculating Sediment Compaction for Radiocarbon Dating of Intertidal Sediments

Radiocarbon ◽

10.1017/s0033822200039734 ◽

2004 ◽

Vol 46 (1) ◽

pp. 421-435 ◽

Cited By ~ 39

Author(s):

M I Bird ◽

L K Fifield ◽

S Chua ◽

B Goh

Keyword(s):

Organic Matter ◽

Bulk Density ◽

Size Distribution ◽

Organic Matter Content ◽

Matter Content ◽

Sediment Accretion ◽

Mangrove Sediments ◽

Sediment Compaction ◽

Accretion Rates ◽

The Difference

This study estimates the maximum and minimum degrees of autocompaction for radiocarbon-dated Holocene mangrove sediments in Singapore, in order to correct apparent sediment accretion rates for the effects of sediment compression due to autocompaction. Relationships developed for a suite of modern (surface) sediment samples between bulk density, particle-size distribution, and organic matter content were used to estimate the initial (uncompacted) bulk density of buried and variably compressed Holocene sediments, based on the grain-size distribution and organic matter content of the sediment. The difference between measured (compacted) and initial (uncompacted) bulk density of each buried sediment interval can be interpreted as the amount of length shortening experienced by each interval since burial. This allows the elevation of samples selected for 14C dating to be corrected for the effects of autocompaction of the underlying sediment sequence, so that accurate estimates of vertical sediment accretion rates can be calculated.The 3 Holocene mangrove sequences analyzed and dated for this study ranged in age from 2000 to 8500 cal BP. The effects of autocompaction are significant, even in comparatively thin sequences, with subsidence of up to 56 cm calculated for carbon-dated samples presently 2 m above incompressible basement. The vertical sediment accretion rates for these mangrove sequences ranged from 0.99 to 6.84 mm/yr and carbon sequestration rates ranged from 0.9 to 1.7 t/ha/yr, all within the range observed for comparable Holocene and modern mangrove sediments elsewhere.

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Potassium in soils under different cropping systems:2. The effects of cropping systems on the retention by the soils of added K not used by crops

The Journal of Agricultural Science ◽

10.1017/s0021859600069550 ◽

1971 ◽

Vol 76 (3) ◽

pp. 553-561 ◽

Cited By ~ 2

Author(s):

T. M. Addiscott ◽

A. E. Johnston

Keyword(s):

Organic Matter ◽

Cropping Systems ◽

Farmyard Manure ◽

Organic Matter Content ◽

Exchange Capacity ◽

Matter Content ◽

Organic C ◽

K Fertilizer ◽

The Difference ◽

Better Than

SUMMARYThe K balance, the difference between K added as fertilizer or farmyard manure (FYM) and K removed by the crops, was calculated for soils from the Classical and Ley-Arable experiments at Rothamsted and for the Woburn Ley-Arable experiment, for the duration of each experiment. Linear regressions on K balance accounted for 78% of the variation in exchangeable K (Ke) and for 83% in K uptake by ryegrass (KP) in the Classical experiments, for 56 and60% respectively in the Ley-Arable experiments at Rothamsted, and for 39 and 6% in the Woburn Ley-Arable experiment.Regressions of Ke and Kp on K balance suggested that, in the Rothamsted Ley-Arable experiments, rather more than half of the K balance remained extractable by ryegrass from the plots with a rotation of crops, and apparently all of the K balance from those under continuous grass. About one-fifth of the K balance remained extractable by ryegrass from the soils in the Rothamsted Classical experiments and soils given FYM retained K slightly better than other soils. With all soils about half the K extractable by ryegrass was exchangeable to ammonium acetate.The plots with FYM or under continuous grass contain more organic matter than other plots in the same experiments. The following possible effects of increasing the organic matter content of the soils were investigated by calculating the multiple regressions of K, and KB on K balance with either percentage of organic C, total CEC, or organic CEC:(1) loss of K decreased by increasing the water retention and lessening leaching;(2) improved K retention by increasing the total cation exchange capacity (CEC) available for K absorption;(3) improved K retention by a mechanism arising from the different selectivities of clay and organic matter for K relative to Ca.In the Classical experiments, where organic matter usually increases because of FYM additions, effect (2) seems the most probable, perhaps because the K given in the FYM was already absorbed by organic exchange sites. In the Ley–Arable experiments, where the K was given mainly as soluble K fertilizer and the organic matter develops mainly under grass, effects (1) or (3) seemed to operate, probably simultaneously.The Woburn Ley-Arable experiment had no continuous grass plots, the soils differed little in organic matter content and no deductions could be made.

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Association of postfire peat accumulation and microtopography in boreal bogs

Canadian Journal of Forest Research ◽

10.1139/x05-115 ◽

2005 ◽

Vol 35 (9) ◽

pp. 2188-2193 ◽

Cited By ~ 17

Author(s):

Brian W Benscoter ◽

Dale H Vitt ◽

R Kelman Wieder

Keyword(s):

Organic Matter ◽

Surface Relief ◽

Accumulation Rate ◽

Organic Matter Content ◽

Matter Content ◽

Site Conditions ◽

Peat Accumulation ◽

The Difference ◽

Rates Of Growth ◽

Sinkhole Lake

Peatlands accumulate organic matter as peat because of disproportionate rates of production and decomposition. However, peat accumulation heterogeneity has not been well studied along the microtopographic gradient (hummocks vs. hollows), particularly with respect to fire. Fire affects peatland species composition by differentially removing vegetation and resetting succession, resulting in peat accumulation changes. We examined peat accumulation and microtopography in two historically burned bogs in Alberta, Canada. Measurements of current and historic microtopography were made, and cores were collected along the gradient to identify depth of peat accumulated since fire, as well as to assess properties of the accumulated peat. Current microtopography is significant and correlated with the immediate postfire surface relief. However, differences in the magnitude of variability between sites suggests that differential rates of growth between features are exacerbated between sites and reflected in bog microtopography. Rates of organic matter accumulation, ranging from 156 to 257 g·m2·year1, were elevated but comparable to published rates of recent accumulation. Organic matter content and accumulation rate were greater for hummocks than hollows at Athabasca bog, but the difference between features diminished at Sinkhole Lake, suggesting that the pattern and properties of peat accumulation and microtopography postfire may be attributable to differences in site conditions.

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Biological strategy to improve decomposition of organic matter in tilapia pond

Acta Limnologica Brasiliensia ◽

10.1590/s2179-975x8419 ◽

2020 ◽

Vol 32 ◽

Author(s):

Gustavo Ruschel Lopes ◽

Hugo Mendes de Oliveira ◽

Gabriel Fernandes Alves de Jesus ◽

Maurício Laterça Martins ◽

Carlos Henrique Araújo de Miranda Gomes ◽

...

Keyword(s):

Organic Matter ◽

Bacillus Subtilis ◽

Nile Tilapia ◽

Organic Matter Content ◽

Matter Content ◽

Control Treatment ◽

Mean Values ◽

Sediment Samples ◽

Decomposition Of Organic Matter ◽

Significant Difference

Abstract: Aim The increment of decomposition of organic matter in sediment samples from Nile tilapia farms was evaluated with the introduction of Bacillus subtilis and B. licheniformis bacteria. Methods Sediment samples placed in 18L plastic boxes received single dose inoculum with the following concentrations: 1.21 x 106 CFU g-1 (equivalent to 75 g ha-1), 2.41 x 106 CFU g-1 (equivalent to 150 g ha-1), 4.82 x 106 CFU g-1 (equivalent to 300 g ha-1) and 1.61 x 107 CFU g-1 (equivalent to 1000 g ha-1), in addition to a control treatment with saline solution only. Organic matter content, total organic carbon (TOC) and oxidizable (OOC), total nitrogen (TN), ratios (TOC: N and OOC: N), clay content, pH in water, Shoemaker, McLean, Pratt index (SMP Index), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) contents, potential acidity (H + Al), cation exchange capacity (CEC) at pH 7.0, base saturation (V) and sum of bases (S). Results The values of OM showed significant difference, between the lowest values (treatments 75, 150 and 300 g ha-1) and the highest value, (control treatment). TOC, OOC, NT and their relationships (TOC: N and OOC: N) showed significant differences between the mean values of the control treatment and the other treatments. Conclusions The addition of Bacillus subtilis and B. licheniformis bacteria increased the decomposition rate of organic matter in sediments samples from Nile tilapia farms.

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Geophysical estimation of shallow permafrost distribution and properties in an ice-wedge polygon-dominated Arctic tundra region

Geophysics ◽

10.1190/geo2015-0175.1 ◽

2016 ◽

Vol 81 (1) ◽

pp. WA247-WA263 ◽

Cited By ~ 32

Author(s):

Baptiste Dafflon ◽

Susan Hubbard ◽

Craig Ulrich ◽

John Peterson ◽

Yuxin Wu ◽

...

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

High Resolution ◽

Water Content ◽

Organic Matter Content ◽

Matter Content ◽

The Arctic ◽

Soil Organic Matter Content ◽

Ice Wedge ◽

Ice Content

Shallow permafrost distribution and characteristics are important for predicting ecosystem feedbacks to a changing climate over decadal to century timescales because they can drive active layer deepening and land surface deformation, which in turn can significantly affect hydrologic and biogeochemical responses, including greenhouse gas dynamics. As part of the U.S. Department of Energy Next-Generation Ecosystem Experiments-Arctic, we have investigated shallow Arctic permafrost characteristics at a site in Barrow, Alaska, with the objective of improving our understanding of the spatial distribution of shallow permafrost, its associated properties, and its links with landscape microtopography. To meet this objective, we have acquired and integrated a variety of information, including electric resistance tomography data, frequency-domain electromagnetic induction data, laboratory core analysis, petrophysical studies, high-resolution digital surface models, and color mosaics inferred from kite-based landscape imaging. The results of our study provide a comprehensive and high-resolution examination of the distribution and nature of shallow permafrost in the Arctic tundra, including the estimation of ice content, porosity, and salinity. Among other results, porosity in the top 2 m varied between 85% (besides ice wedges) and 40%, and was negatively correlated with fluid salinity. Salinity directly influenced ice and unfrozen water content and indirectly influenced the soil organic matter content. A relatively continuous but depth-variable increase in salinity led to a partially unfrozen saline layer (cryopeg) located below the top of the permafrost. The cryopeg environment could lead to year-round microbial production of greenhouse gases. Results also indicated a covariability between topography and permafrost characteristics including ice-wedge and salinity distribution. In addition to providing insight about the Arctic ecosystem, through integration of lab-based petrophysical results with field data, this study also quantified the key controls on electric resistivity at this Arctic permafrost site, including salinity, porosity, water content, ice content, soil organic matter content, and lithologic properties.

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HEAVY METAL SPECIATION IN BOTTOM SEDIMENTS OF THE VYSHNEVOLOTSKY RESERVOIR

Moscow University Bulletin. Series 4. Geology ◽

10.33623/0579-9406-2018-3-46-54 ◽

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.

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