Contributions of carbonates to soil CO2 emissions

Ramnarine, R., Wagner-Riddle, C., Dunfield, K. E. and Voroney, R. P. 2012. Contributions of carbonates to soil CO 2 emissions. Can. J. Soil Sci. 92: 599–607. Carbon dioxide (CO2) is released in soil as a by-product of microbial and root respiration, but soil carbonates may also be a source of CO2 emissions in calcareous soils. Global estimates of inorganic carbon range from 700 to 900 Pg as carbonates stored in soils, representing a significant potential source of CO2 to the atmosphere. While previous studies have focused on the total CO2 efflux from the soil, our goal was to identify the various sources and their contribution to total CO2 emissions, by measuring the isotopic signature of the CO2 emitted from the soil. Calcareous Luvisolic silt loam soil samples were obtained from conventional tillage (CT) and no-tillage (NT) plots in southern Ontario, Canada. Soil samples (root- and residue-free) were laboratory-incubated for 14 d and the isotopic signature of the CO2 (δ13CCO2) released was analyzed using isotope ratio mass spectrometry. Isotopic measurement was essential in quantifying the abiotic CO2 production from carbonates, due to the unique δ13C signature of carbonates and soil organic matter. A two-end member mixing model was used to estimate the proportion of CO2 evolved from soil carbonates and soil organic matter decomposition. Analysis of emitted CO2 collected after the 14-d incubation indicate that the proportion of CO2 originating from soil inorganic carbon was 62 to 74% for CT soil samples, and 64 to 80% for NT soil samples. Further work is recommended in the quantification of CO2 emissions from calcareous soils, and to determine the transferability of laboratory results to field studies.

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Post-thinning soil organic matter evolution and soil CO2 effluxes in temperate radiata pine plantations: impacts of moderate thinning regimes on the forest C cycle

Canadian Journal of Forest Research ◽

10.1139/x2012-137 ◽

2012 ◽

Vol 42 (11) ◽

pp. 1953-1964 ◽

Cited By ~ 4

Author(s):

Irene Fernandez ◽

Juan Gabriel Álvarez-González ◽

Beatríz Carrasco ◽

Ana Daría Ruíz-González ◽

Ana Cabaneiro

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Radiata Pine ◽

Soil Samples ◽

Mitigation Strategies ◽

Change Scenario ◽

Soil C ◽

C Storage ◽

C Cycle ◽

C And N

Forest ecosystems can act as C sinks, thus absorbing a high percentage of atmospheric CO2. Appropriate silvicultural regimes can therefore be applied as useful tools in climate change mitigation strategies. The present study analyzed the temporal changes in the effects of thinning on soil organic matter (SOM) dynamics and on soil CO2 emissions in radiata pine ( Pinus radiata D. Don) forests. Soil C effluxes were monitored over a period of 2 years in thinned and unthinned plots. In addition, soil samples from the plots were analyzed by solid-state 13C-NMR to determine the post-thinning SOM composition and fresh soil samples were incubated under laboratory conditions to determine their biodegradability. The results indicate that the potential soil C mineralization largely depends on the proportion of alkyl-C and N-alkyl-C functional groups in the SOM and on the microbial accessibility of the recalcitrant organic pool. Soil CO2 effluxes varied widely between seasons and increased exponentially with soil heating. Thinning led to decreased soil respiration and attenuation of the seasonal fluctuations. These effects were observed for up to 20 months after thinning, although they disappeared thereafter. Thus, moderate thinning caused enduring changes to the SOM composition and appeared to have temporary effects on the C storage capacity of forest soils, which is a critical aspect under the current climatic change scenario.

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Estimation of soil organic matter using proximal and satellite sensors after a wildfire in Mediterranean Croatia

10.5194/egusphere-egu21-3896 ◽

2021 ◽

Author(s):

Iva Hrelja ◽

Ivana Šestak ◽

Igor Bogunović

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Spectral Data ◽

Near Infrared ◽

Mean Squared Error ◽

Nir Spectroscopy ◽

Soil Samples ◽

Least Squares Regression ◽

Macro Scale ◽

Sentinel 2

Spectral data obtained from optical spaceborne sensors are being recognized as a valuable source of data that show promising results in assessing soil properties on medium and macro scale. Combining this technique with laboratory Visible-Near Infrared (VIS-NIR) spectroscopy methods can be an effective approach to perform robust research on plot scale to determine wildfire impact on soil organic matter (SOM) immediately after the fire. Therefore, the objective of this study was to assess the ability of Sentinel-2 superspectral data in estimating post-fire SOM content and comparison with the results acquired with laboratory VIS-NIR spectroscopy.The study is performed in Mediterranean Croatia (44&#176; 05&#8217; N; 15&#176; 22&#8217; E; 72 m a.s.l.), on approximately 15 ha of fire affected mixed Quercus ssp. and Juniperus ssp. forest on Cambisols. A total of 80 soil samples (0-5 cm depth) were collected and geolocated on August 22nd 2019, two days after a medium to high severity wildfire. The samples were taken to the laboratory where soil organic carbon (SOC) content was determined via dry combustion method with a CHNS analyzer. SOM was subsequently calculated by using a conversion factor of 1.724. Laboratory soil spectral measurements were carried out using a portable spectroradiometer (350-1050 nm) on all collected soil samples. Two Sentinel-2 images were downloaded from ESAs Scientific Open Access Hub according to the closest dates of field sampling, namely August 31st and September 5th 2019, each containing eight VIS-NIR and two SWIR (Short-Wave Infrared) bands which were extracted from bare soil pixels using SNAP software. Partial least squares regression (PLSR) model based on the pre-processed spectral data was used for SOM estimation on both datasets. Spectral reflectance data were used as predictors and SOM content was used as a response variable. The accuracy of the models was determined via Root Mean Squared Error of Prediction (RMSEp) and Ratio of Performance to Deviation (RPD) after full cross-validation of the calibration datasets.The average post-fire SOM content was 9.63%, ranging from 5.46% minimum to 23.89% maximum. Models obtained from both datasets showed low RMSEp (Spectroscopy dataset RMSEp = 1.91; Sentinel-2 dataset RMSEp = 0.99). RPD values indicated very good predictions for both datasets (Spectrospcopy dataset RPD = 2.72; Sentinel-2 dataset RPD = 2.22). Laboratory spectroscopy method with higher spectral resolution provided more accurate results. Nonetheless, spaceborne method also showed promising results in the analysis and monitoring of SOM in post-burn period.Keywords: remote sensing, soil spectroscopy, wildfires, soil organic matterAcknowledgment: This work was supported by the Croatian Science Foundation through the project "Soil erosion and degradation in Croatia" (UIP-2017-05-7834) (SEDCRO). Aleksandra Per&#269;in is acknowledged for her cooperation during the laboratory work.

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Metal contamination of urban soils in Cork, Ireland

10.5194/egusphere-egu21-15261 ◽

2021 ◽

Author(s):

Hannah Binner ◽

Timothy Sullivan ◽

Maria E. Mc Namara

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Metal Contamination ◽

Urban Soils ◽

Soil Samples ◽

Ex Situ ◽

City Centre ◽

Metal Concentrations ◽

Ph Values ◽

Background Levels

Soil contamination is widespread across Europe. In particular, contamination of urban soils by metals is poorly characterised. This is a major environmental concern, especially given that urban recreational amenities may be located on former industrial sites and/or may possess ex situ soils derived from industrial areas. We surveyed soils from nine urban recreational sites (15 samples per site) in Cork city in order to assess the degree of metal contamination. The results show that Pb concentrations exceed national background levels in all soil samples from all sites by a mean of 600 % and at least 140 %. Mn, Fe and Zn are enriched above background levels in all soil samples from three (Mn and Fe) to five (Zn) of the sites and, at the remaining sites, show 7 &#8211; 14 localised hotspots. Similar hotspots characterise Cu, Rb and Sr, which each exceed background levels at eight or more sampling locations at four sites. Co, Ni, As and Sn concentrations exceed background levels in at least three hotspots at each of three to six sites. Overall, metal concentrations are highest in the sites closest to the city centre, reflecting diverse sources that potentially include traffic and current and historical domestic coal burning and industry. At each urban site, the element grouping Zn and Pb recurs in 50 to 80 % of locations and enrichment in the element grouping Mn, Fe, Cu, Zn and Pb recurs in approx. 50 % of locations; Ni and As recur in approx. 10 % of the locations. At three sites, elevated concentrations of Mn, Fe, Cu, Zn and Pb are associated with high LOI (Loss-on-ignition) values &#8211; a proxy for the amount of soil organic matter present &#8211; and near-neutral pH values. Conversely, low LOI and acidic pH values are associated with lower concentrations of these elements. This indicates that soil metal concentrations are influenced by the amount of organic matter present and by pH. &#160;Future analyses and experiments will further investigate links between soil organic matter and metal concentrations.

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Soil fertility status of some of the intensive crop growing areas under major agroecological zones of Bangladesh

Bangladesh Journal of Agricultural Research ◽

10.3329/bjar.v41i4.30705 ◽

2016 ◽

Vol 41 (4) ◽

pp. 735-757 ◽

Cited By ~ 3

Author(s):

NC Shil ◽

MA Saleque ◽

MR Islam ◽

M Jahiruddin

Keyword(s):

Organic Matter ◽

Soil Fertility ◽

Calcareous Soils ◽

Clay Content ◽

Soil Samples ◽

Exchangeable K ◽

Low Level ◽

Fertility Status ◽

Agroecological Zones ◽

High Level

Laboratory studies on soil fertility evaluation was carried out across major agroecological zones (AEZs) of Bangladesh to know the nutrient status of soils and to relate those with soil properties like pH, organic matter, CEC, and clay content. Thirty five composite soil samples were collected from intensive crop growing sites, which covered 17 AEZs of Bangladesh. After proper processing, the samples were analyzed for texture, pH, organic carbon, CEC, exchangeable cations (K, Ca, Mg and Na), total N, available P and S following standard methods. The textural class of the soils collected from AEZ 12 and 13 appeared to be mostly clay. Clay loam soil was found in AEZ 4, 8, 9, 11, 25 and 28. Loamy soil was seen in AEZ 1 while AEZ 22, 23 and 29 were mostly sandy textured. The results revealed that 65.7% of the tested soil was acidic while 25.7% was alkaline in nature. All the tested soils showed lower pHKCl compared to pHH2O thus possessed negative charge. About 68.6% of the collected soils contained low (1.10-1.70%) level of organic matter, 25.7% soils retained it at medium level (1.71-2.40) and 5.7% soils at very low level (<1.0%). All the tested soils appeared to be deficient (< 0.12%) in nitrogen content. 68.6% soil samples had the low level of available P while only 8.6% retained it an optimum amount. About 80% of the tested soils contained low level of available S (7.9- 14.7 mg kg -1) although coastal regions soils hold higher amount of available S. High CEC (20-38 cmol kg-1) was found in clay rich soils of AEZ 10, 11, 12, and 13. Study revealed that 40% of the collected soils were very low, 31.4% were low, 8.6% each of medium and optimum, and 11.4% contained high level of exchangeable K. The calcareous soils (AEZ 10, 11, 12 and 13) contained very high level of Ca. Non calcareous soils also showed fairly good level of Ca content except AEZ 1, 3, 23 and 29. Sandy textured soils of greater Dinajpur, Rangpur, Moulvibazar showed lower level of exchangeable Mg. About 86% of the tested soils had the lower (< 2%) potassium saturation percentage (KSP), which needs K application for sustainable crop production. Estimate showed that 44% variability for CEC may be attributed by clay content and the relationship was significant (p = 0.05). Again, 50.4 and 65.6% variability in exchangeable K and Mg, respectively may be governed by clay content of the soils, while such relationship for Ca was non-significant. CEC may contribute 62.2, 92.3 and 83.9% variability for exchangeable K, Ca and Mg content in soils, respectively. The fertility status of most of the studied soils (except AEZ 10, 12, 13 and to some extent 11) appeared to be low to very low, which demand judicious management in order to achieve food security and to conserve the soil fertility.Bangladesh J. Agril. Res. 41(4): 735-757, December 2016

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Potential relevance of Mortierella alpina as a source of ice nucleating particles in soil

10.5194/bg-2018-79 ◽

2018 ◽

Author(s):

Franz Conen ◽

Mikhail V. Yakutin

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Soil Fungus ◽

Soil Samples ◽

Mortierella Alpina ◽

Soil Particles ◽

The Tropics

Abstract. Soil organic matter carries ice nucleating particles (INP) of which the origin is hard to define and that are active at slight supercooling. The discovery and characterisation of INP produced by the widespread soil fungus Mortierella alpina permits a more targeted investigation of the likely origin of INP in soils. We searched for INP with characteristics similar to those reported for M. alpina (INPM-like) in 20 soil samples from four areas in the northern midlatitudes and one area in the tropics. In the 15 samples where we could detect INPM-like, they constituted between 1 and 94 % (median 11 %) of all INP active at −10 °C or warmer associated with soil particles

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INFLUENCE OF FARMYARD MANURE ON RETENTION AND AVAILABILITY OF NICKEL, ZINC AND LEAD IN METAL-CONTAMINATED CALCAREOUS LOAM SOILS

Journal of Environmental Engineering and Landscape Management ◽

10.3846/16486897.2016.1254639 ◽

2017 ◽

Vol 25 (3) ◽

pp. 289-296 ◽

Cited By ~ 5

Author(s):

Muhammad Abbas AZIZ ◽

Hamaad Raza AHMAD ◽

Dennis L. CORWIN ◽

Muhammad SABIR ◽

Khalid Rehman HAKEEM ◽

...

Keyword(s):

Organic Matter ◽

Retention Time ◽

Farmyard Manure ◽

Calcareous Soils ◽

Field Capacity ◽

Soil Samples ◽

Continuous Irrigation ◽

Moisture Contents ◽

Nickel Zinc ◽

Chloride Salts

Continuous irrigation of soils with untreated effluents can result in the accumulation and translocation of some metals in the soils and plants. Application of farmyard manure (FYM) to such soils may increase or decrease their availability and retention time. Calcareous soils contaminated with 100, 200, and 400mg kg–1 Ni, Zn, and Pb as chloride salts were used, and farmyard manure added (40g kg–1 for 90 days) with moisture contents at field capacity. Soil samples were drawn at 30 day intervals, and metals extracted with (AB-DTPA) C14H23NO3O10. With FYM application of 400 mg kg–1, Ni availability increased from 179 (day 30) to 240 mg kg–1(day 90); Zn from 163 (day 30) to 230 mg kg–1 (day 90), but, Pb decreased from 214 to 161 mg kg–1. FYM forms multi-dentate complex which greatly enhances the Ni and Zn solubility, and organic matter immobilizes Pb in the soil.

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Compound-specific δ2H using analytical pyrolysis (Py-CSIA) for assessing source and processes of soil organic matter driven by climatic changes within a Mediterranean evergreen oak forest (dehesas)

10.5194/egusphere-egu21-14610 ◽

2021 ◽

Author(s):

Layla M. San-Emeterio ◽

Ignacio Pérez-Ramos ◽

Maria Teresa Domínguez-Núñez ◽

Francisco Javier González-Vila ◽

José Antonio González-Pérez

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Technical Assistance ◽

Isotope Composition ◽

Climatic Conditions ◽

Soil Samples ◽

Tree Canopy ◽

Analytical Pyrolysis ◽

Exchangeable Hydrogen ◽

Evergreen Oak

Soil organic matter (SOM) is composed of multiple components from the living material, such as phenolic compounds, organic acids, lipids, peptides, polyesters, etc. A relevant part of these compounds forms part of supramolecular structures or mineral associations. Non-exchangeable hydrogen in SOM compounds is worth of study as an approach to estimate dynamic processes such as stabilization, mineralization, or biodegradation. The determination of H isotopes in SOMs faces analytical challenges related with e.g., the strength of the H bond, its exchangeability with ambient H from water or the instability of the isotopic analysis [1]. Nonetheless, along with the study of C isotopes, the study of H isotopes may certainly result in a complementary to give some light in this complex system, estimate the fate of organic compounds, and to better understand the link between hydrogen and carbon cycles in SOM [2].In this communication, we describe and validate a methodology based on analytical pyrolysis for the direct measure of compound-specific H isotope composition (&#948;2H) in soil samples. The technique combines Py-GC with a high-temperature conversion reactor and a continuous flow isotope ratio mass spectrometer (IRMS) (Py-GC-HTC-IRMS).Composite dehesa surface (0-10 cm) soil samples (Pozoblanco, C&#243;rdoba, Spain) were taken from four forced climatic treatment plots representing warming (W), drought (D), its combination (W+D), and control (D), installed in two different habitats: under evergreen oak canopy and in the open pasture. The samples were analysed in triplicate by conventional analytical pyrolysis (Py-GC/MS) and in parallel for &#948;2H Py-CSIA using the same chromatographic conditions and separation column type.Up to 32 compounds were identified by Py-GC/MS, which H isotope composition corresponded presumably to non-exchangeable H, and with origin mainly from lignin (G- and S- units) and lipids. The H isotope composition showed an estimated average of -55 &#8240; &#177; 7.09 for G-lignin units, -64 &#8240; &#177; 8.64 S-lignin units and lighter -112 &#8240; &#177; 4.32 for fatty acids (-109 &#8240; &#177; 3.65) and the n-alkane series (C-19 to C-31). Significant differences are reportedly driven by the differences in habitat: more depleted &#948;2H values were found in SOM produced in the open pasture than under the tree canopy. In addition, a &#948;2H enrichment is observed for lignin-derived compounds in SOM under the W+D treatment.The technique used and tested is expected to bring novelty results in relation to the processes affecting the isotopic composition of non-exchangeable hydrogen exerted by climatic treatments on diverse SOM specific compounds. Besides presenting the analytical challenges that are faced, we will discuss the effects of canopy and climatic treatments to tackle potential harsh climatic conditions as predicted, especially in Mediterranean areas.&#160;Acknowledgement: INTERCARBON project (CGL2016-78937-R), DECAFUN (CGL2015-70123-R). MICIU for funding FPI research grants (BES-2017-07968). Mrs Desir&#233; Monis, Mrs Alba M. Carmona & Mr Eduardo Guti&#233;rrez Gonz&#225;lez are acknowledged for technical assistance.[1] Paul, A. et al (2016). Biogeosciences, 13, 6587&#8211;6598.[2] Seki, O. et al (2010). Geochimica et Cosmochimica Acta,&#160;74(2), 599-613.

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Effect of Different Doses of Nutrients on Changes of Soil Organic Matter in Rendzic Leptosol

Agriculture (Pol nohospodárstvo) ◽

10.2478/v10207-012-0014-7 ◽

2012 ◽

Vol 58 (4) ◽

pp. 131-137

Author(s):

Vladimír Šimanský ◽

Erika Tobiašová

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Soil Samples ◽

Water Soluble ◽

Hot Water ◽

Fertilizer Treatment ◽

Content Increase ◽

Npk Fertilizer ◽

Different Doses

Abstract The effect of different doses of NPK fertilizer on the changes in quantity and quality of soil organic matter (SOM) in Rendzic Leptosol was evaluated. Soil samples were taken from three treatments of different fertilization: (1) control - without fertilization, (2) NPK 1 - doses of NPK fertilizer in 1st degree intensity for vine, and (3) NPK 3 - doses of NPK fertilizer in 3rd degree intensity for vine in the vineyard. Soil samples were collected in years 2008-2011 during the spring. The higher dose of NPK fertilizer (3rd degree intensity of vineyards fertilization) was responsible for the higher content of labile carbon (by 21% in 0-0.3 m and by 11% as average of the two depths 0-0.3 m and 0.3-0.6 m). However, by application of a higher dose of NPK (1.39%) in comparison to no fertilizer treatment (1.35%) or NPK 1 (1.35%) the tendency of total organic carbon content increase and hot-water soluble carbon decrease were determined. Fertilization had a negative effect on SOM stability. Intensity of fertilization affected the changes in quantity and quality of SOM; therefore it is very important to pay attention to the quantity and quality of organic matter in productive vineyards.

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Traffic and tillage effects on wheat production on the Loess Plateau of China: 1. Crop yield and SOM

Soil Research ◽

10.1071/sr07106 ◽

2008 ◽

Vol 46 (8) ◽

pp. 645 ◽

Cited By ~ 25

Author(s):

Hao Chen ◽

Yuhua Bai ◽

Qingjie Wang ◽

Fu Chen ◽

Hongwen Li ◽

...

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Field Experiment ◽

Loess Plateau ◽

Crop Yield ◽

Soil Profile ◽

Conventional Tillage ◽

Zero Tillage ◽

The Loess Plateau ◽

Controlled Traffic

Challenges for dryland farming on the Loess Plateau of China are continuous nutrient loss, low soil organic matter and crop yield, and soil degradation. Controlled traffic, combined with zero or minimum tillage and residue cover, has been proposed to improve soil structure and crop yield. From 1998 to 2006, we conducted a field experiment comparing soil organic matter and wheat productivity between controlled traffic and conventional tillage farming systems. The field experiment was conducted using 2 controlled traffic treatments (zero tillage with residue cover and no compaction, shallow tillage with residue cover and no compaction) and a conventional tillage treatment. Results showed that controlled traffic treatments significantly increased soil organic matter and microbial biomass in the 0–0.30 m soil profile. Controlled traffic with zero tillage significantly increased total N in the 0–0.05 m soil profile. The mean yield over 8 years of controlled traffic treatments was >10% greater than that of conventional tillage. Controlled traffic farming appears to be a solution to the cropping problems faced on the Loess Plateau of China.

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Hamburg University Radiocarbon Dates II

Radiocarbon ◽

10.1017/s0033822200003519 ◽

1977 ◽

Vol 19 (2) ◽

pp. 170-182 ◽

Cited By ~ 3

Author(s):

H W Scharpenseel ◽

H Schiffmann

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Soil Samples ◽

Radiocarbon Dates ◽

Soil Organic Matter Fractions ◽

Single Screw ◽

Organic Matter Fractions

Radiocarbon measurements mainly on soil samples and soil organic matter fractions are being continued. Sample benzene preparation follows Scharpenseel & Pietig (1969; 1970a). Radioactivity is measured in single screw cap quartz vials using a Packard Tri-Carb 3075 as well as a Berthold Betaszint BF 5000.

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