Organic Carbon content (weight percentage) at each field site

Top PDF Organic Carbon content (weight percentage) at each field site:

Effects of Soil Compaction and Organic Carbon Content on Preferential Flow in Loamy Field Soils

Effects of Soil Compaction and Organic Carbon Content on Preferential Flow in Loamy Field Soils

Bulk density was identified as the main driver for several soil functional properties at both sites but, in general, stronger correla- tions were found for the Silstrup samples. Bulk density was posi- tively correlated with apparent dispersivity but negatively correlated with 5% mass arrival time and log K SAT (Faardrup site only) and ε −20 . Texture parameters were not correlated to transport of either air or tritium, but this may be caused by relatively small soil textural variations observed at each field site.

11 Read more

Characterizing organic carbon dynamics during biostimulation of a uranium contaminated field site

Characterizing organic carbon dynamics during biostimulation of a uranium contaminated field site

2003; Kang and Mitchell 2013). Spectroscopic techniques might offer new insights into the carbon dynamics of a biostimulated system both during active remediation and post-stimulation. The purpose of this study was to determine, if in-situ biostimulation would produce SMP in measurable quantities and how long SMP production would persist once acetate addition was terminated. In addition, an attempt was made to close the carbon and electron mass balance for the biostimulated system to determine possible carbon sinks that are not accounted for solely by biomass growth and substrate utilization. Dissolved organic carbon and acetate were measured to estimate the amount of SMP. A conceptual model was used to divide SMP into two pools based on the postulated origin: UAP and BAP. Bulk analyses were used to characterize SMP by spectroscopic properties. Fluorescence spectroscopy was used to differentiate between UAP and BAP based on EEMs characteristics while SUVA was used to assess aromaticity and hence bioavailability of SMP compared to background DOC.
Show more

27 Read more

Foresttopsoil organic carbon content inSouthwest Bohemiaregion

Foresttopsoil organic carbon content inSouthwest Bohemiaregion

Of the tested classifiers, both tree species and several of the stand site type categories revealed significant differences in SOC in both organic and mineral layer. This is vital for the purpose of regional extrapolation, which should be based on the classifier that suitably reflects the overall site conditions, including climate, soil type and type of forest vegetation. In this respect, the categoriza- tion based on forest site types as used in the Czech forest typology seems to be promising. Forest type categories integrate the key site parameters and provide good approximate characteristics that affect SOC. Although this study provides a good foundation for categorization of SOC by stand site types, it is obvious that further analysis is needed and it should involve also other regions of the country. Since the map of forest site types is already available in digital form for the whole country (Macků – unpublished results), it could be used to target the most important forest site types and optimally stratify additional soil sampling needed.
Show more

12 Read more

Organic carbon at a remote site of the western Mediterranean Basin: sources and chemistry during the ChArMEx SOP2 field experiment

Organic carbon at a remote site of the western Mediterranean Basin: sources and chemistry during the ChArMEx SOP2 field experiment

reservoir layers at high altitudes described in several studies (Pey et al., 2009; Minguillón et al., 2015; Ripoll et al., 2015). The second period of long-range transported anthro- pogenic continental emissions is characterized by less in- tense anthropogenic gas-phase PMF factors, especially for the long-lived anthropogenic factor, and a clear predomi- nance of the organic fraction for aerosols. Aerosol mass con- centrations are also lower by approximately 50 % compared to the first period. During both periods, a non-negligible bio- genic influence is also observed from primary and secondary biogenic PMF VOC factors. This is even more pronounced for the second “anthropogenic” period. During these periods, it is therefore likely that oxygenated VOCs and OOAs have both biogenic and anthropogenic origins in variable propor- tions.
Show more

29 Read more

Connotation of Natural Coagulants on Total Organic Carbon content of water

Connotation of Natural Coagulants on Total Organic Carbon content of water

Experimental procedure: A conventional jar test apparatus was employed for the process of coagulation and flocculation. All tests were carried out with 1 L samples in 2-L beakers. Beakers were filled with 1000 ml of the synthetic water, and placed on each slot in a jar tester. Coagulant was added into each beaker at various doses and agitated at two different mixing speed and time: 100 rpm for 1 min and then reduced to 20 rpm for 30 min. The coagulant dose was added at four concentrations i.e 0.1, 0.2, 0.3 and 0.4 mg/l. The coagulation was performed at three different pH conditions by adding 0.1 M H 2 SO 4 and 0.1 M NaOH in all coagulation tests. After sedimentation for 20 min, an aliquot of 10 ml was sampled from the mid depth of the beaker and residual turbidity was determined. Turbidity measurements were conducted using nephelometricturbidimeter (ELICO, CL52D). The pH values of samples were measured using pH meter (ELICO, L1 126).
Show more

9 Read more

Manure and fertilizer effects on carbon balance and organic and inorganic carbon losses for an irrigated corn field

Manure and fertilizer effects on carbon balance and organic and inorganic carbon losses for an irrigated corn field

Data from each irrigation in 2003 and 2004 were analyzed via ANOVA, PROC Mixed (SAS Institute, 2009) using a repeat- ed measures approach, which accounted for correlations among the values of response variables measured from one irrigation to the next. The model included treatment, year, and irrigation as fixed effects, and block with its associated interactions as random effects. Response variables (runoff C concentrations and losses for individual irrigations) were transformed using common Log or square root to stabilize variances and improve normality. The LSmeans and 95% confidence intervals were back transformed to original units for reporting. An ANOVA on season-long cu- mulative values was performed using PROC Mixed to determine the effect of treatment and year on each parameter. The model included treatment and year as fixed effects with block and its as- sociated interactions as random effects. No transformation of the raw data was needed to analyze season-long cumulative values. All analyses were conducted using a P = 0.05 significance level.
Show more

16 Read more

Field of the Dissolved Organic Matter Content in the Taganrog Bay (the Sea of Azov)

Field of the Dissolved Organic Matter Content in the Taganrog Bay (the Sea of Azov)

28. Shevchenko, V.P., Shirokova, L.S., Zdorovennov, R.E., Novigatskiy, A.N., Pokrovskiy, O.S. and Politova N.V., 2012. Raspredelenie Rastvorennogo Organicheskogo Ugleroda v Mar- ginal'nom Fil'tre Reki Kemi (Beloe More) v Letniy Period [The Distribution of Dissolved Or- ganic Carbon in the Marginal Filter of the Kemi River (the White Sea) in Summer]. In: KarRC RAS, 2012. Organicheskoe Veshchestvo i Biogennye Elementy vo Vnutrennikh Vodoemakh i Morskikh Vodakh [Organic Matter and Nutrients in Inland and Marine Waters]: Proc. of 5 th All-Russian Symposium with International Participation, September 10-14, 2012.
Show more

13 Read more

The impact of mulch type on soil organic carbon and nitrogen pools in a sloping site

The impact of mulch type on soil organic carbon and nitrogen pools in a sloping site

(2011) used organic mulching with four different biomass materials, cogongrass (Imperata cylindrica), oak (Quercus fabri), Chinese coriaria (Coriaria nepalensis) and brackenfern (Pteridium aquilinum) in Populus spp. plantations in China. Those authors concluded that although mulching improved soil N, the degree of N improvement was influenced by decay rate and initial nutrient content of the mulching materials. In contrast, a trial of inorganic and organic mulches, including alfalfa straw, forest litter and polyethylene, revealed no significant difference in SOC, TN and nitrate among the treatments. Inorganic mulch materials do not have organic content but may increase soil moisture, thereby accelerating organic matter decomposition and improving their incorporation in soil (Barajas-Guzmán et al. 2006). In the present study, despite the fact granite was an inorganic mulch, the SOM under granite mulch did not differ significantly from hydro-seeding but was significantly different to the forest mulch, even though these two treatments had similar vegetative cover. This suggests that the presence of large rocks acts as a physical barrier to the incorporation of litter leaving the litter susceptible to wind and water transport processes. Greater soil improvement under forest mulch compared to hydro-seeding and granite mulches are associated with higher organic matter of the mulch content and greater soil moisture preservation.
Show more

18 Read more

Organic carbon content and mineralization characteristics of soil in a subtropical Pinus massoniana forest

Organic carbon content and mineralization characteristics of soil in a subtropical Pinus massoniana forest

4 Beijing Flowers Company, Tian Huiyuan Academy, Beijing, P. R. China _____________________________________________________________________________________________ ABSTRACT Soils were collected from a broad leaf-Pinus massoniana mixed forest, a Chinese fir (Cunninghamialan ceolata)-Pinus massoniana mixed forest, and a pure Pinus massoniana subtropical forest for subsequent analyses to compare characteristics of soil organic carbon and microbial biomass carbon content. Soil organic carbon mineralization characteristics were further modeled using a double exponential equation. The soil organic carbon and active carbon content displayed obvious surface accumulation and decreased with increasing soil depth in all three forest types. Soil microbial carbon in the two mixed forests was primarily concentrated at depths of 0-20 cm, and significant differences were found between the topsoil and subsoil. However, soil microbial carbon in the pure forest exhibited a gradual vertical change without significant differences between soil layers. Soil organic carbon mineralization characteristics in each layer could be well represented using a double exponential equation, with similar fitting results displaying a strong initial reaction intensity followed by a gradual decrease at later stages in all three forest types. Soil organic carbon mineralization reactions at depths of 0-10 cm were always strong due to high levels of soil organic carbon, active carbon content, and greater microbial activity; however, there were no significant differences among layers below 10 cm. More intensive soil organic carbon mineralization processes were observed in mixed forests compared with the pure forest.
Show more

7 Read more

Soil Organic Carbon Content and Quality in Post-Agricultural Northern Hardwood forests

Soil Organic Carbon Content and Quality in Post-Agricultural Northern Hardwood forests

Developing a land-use history for a given locale often requires on- and off-site investigation. Initially, aerial photos, which date back to the 1930s, and public records offices were useful. Some of the current owners’ families have occupied the land in WNE for up to 5 generations, and those individuals often knew the history of the different areas of their farms. For sites with no documented or limited oral history, we used several field criteria to evaluate the last use. Stone walls are ubiquitous in the western New England landscape. Settlers built these walls around the borders of agricultural plots as they cleared their land for plowing. The presence of stone walls demonstrates that some form of agricultural use occurred for a substantial amount of time, as it usually took multiple generations to clear all of the large rocks from each acre of these till-derived soils. The size, orientation and placement on the stem of tree branches on the borders of old fields were useful indicators of cleared areas.
Show more

326 Read more

Reference Area Method for Mapping Soil Organic Carbon Content at Regional Scale

Reference Area Method for Mapping Soil Organic Carbon Content at Regional Scale

The Lysina CZO is an experimental catchment to study the resilience of soil functions to acid deposition and other impacts in heavily managed forest land used for timber production. It represents managed land as an important economic asset where soil is under threat from industrial pollution. The Lysina CZO is situated in western Bohemia, the Czech Republic and more specific in the Protected Area Slavkovsky Forest, 120 km W from Prague, 10 km N from Marienbad. The catchment covers an area of around 0.40 km 2 and is covered with a Norway spruce (Picea abies) monoculture (Navratil et al., 2007). Altitude of the site is ranges between 829 and 949 m above sea level with a mean slope gradient of 11.5%. The region was not glaciated during Wisconsinan time, and soils are developed from residuum bedrock. Soils in the catchment are Dystric Cambisols. The catchment is drained by a perennial stream that begins at about 900 m above sea level. Lysina represents sites with acid-vulnerable soil and water environment due to base-poor rock (Kram et al., 2012). The main focus is on description of long-term hydro- biogeochemical patterns in the magnesium-poor and acid-sensitive Lysina catchment. Research activities have started in 1988 and include among others: study of element fluxes and pools, wet and dry deposition, internal recycling in trees, soil exchange processes, chemical weathering, nutritional status of trees and toxic metals speciations, modeling predictions of hydrologic, hydro-chemical and soil chemical status.
Show more

9 Read more

Evaluation of Soil Organic Carbon and Soil Moisture Content from Agricultural Fields in Mississippi

Evaluation of Soil Organic Carbon and Soil Moisture Content from Agricultural Fields in Mississippi

In this study samples from the same field were com- posited based on depth in order to achieve an average across the field at each respective depth. Once aggre- gated the samples were finely ground using a Dynacrush Soil Crusher (Custom Laboratory Equipment Inc., Or- ange City, FL). Pulverization was done until a majority of the sample could pass through a 60-mesh sieve. Siev- ing helped to ensure particles were 250 µm or less and also aided in the complete removal of any stray litter that may have been erroneously captured in the sample. A portion of the pulverized sample was then transferred to a 4 milliliter glass vial and dried at 105˚C for one hour to remove any latent moisture acquired during pulverization.
Show more

10 Read more

Research of Organic Carbon and Carbonate Content in the Bottom Sediments of the Crimean Southern Coast Shelf

Research of Organic Carbon and Carbonate Content in the Bottom Sediments of the Crimean Southern Coast Shelf

The testing ground is ~1 × 1.5 km water area, including Limensky Gulf (Blue Bay) and a stationary oceanographic platform, which is situated at ~600 m distance from the coast (the depth of the site is 28 m; coordinates 44°23′35″ N, 33°59′04″ E). Coastal zone in the testing ground area is composed of the Taurian Series deposits. Limensky Gulf is bounded from the East by the spurs of Mount Koshka, from the West – by Cape Kikineiz. The Gulf is stretched in the latitudinal direction and is characterized by high shores. The West coast is composed of series of clay and loam sediments with inclusions of Jurassic limestone detrital material (frequently with the size of several meters). The shores in the central part of the Gulf are steep, clayey and with an active abrasion zone. Rocky shores of the eastern part consist of the Upper Jurassic limestone blocks [7]. The Limenka River (temporary watercourse with seasonal flooding regime) discharges the Gulf in its eastern part.
Show more

11 Read more

Converting loss-on-ignition to organic carbon content in arable topsoil: Pitfalls and proposed procedure

Converting loss-on-ignition to organic carbon content in arable topsoil: Pitfalls and proposed procedure

Summary Assessments of changes in soil organic carbon (SOC) stocks depend heavily on reliable values of SOC content obtained by automated high-temperature C analysers. However, historical as well as current research often relies on indirect SOC estimates such as loss-on-ignition (LOI). In this study, we revisit the conversion of LOI to SOC using soil from two long-term agricultural field experiments and one arable field with different contents of SOC, clay and particles < 20 μm (Fines20). Clay-, silt- and sand-sized fractions were isolated from the arable soil. Samples were analysed for texture, LOI (500 ∘ C for 4 hours) and SOC by dry combustion. For a topsoil with 2 g C and 30 g clay 100 g −1 soil, converting LOI to SOC by the conventional factor 0.58 overestimated the SOC stock by 45 Mg C ha −1 . The error increased with increasing contents of clay and Fines20. Converting LOI to SOC by a regression model underestimated the SOC stock by 5 Mg C ha −1 at small clay and Fines20 contents and overestimated the SOC stock by 8 Mg C ha −1 at large contents. This was due to losses of structural water from clay minerals. The best model to convert LOI to SOC incorporated clay content. Evaluating this model against an independent dataset gave a root mean square error and mean error of 0.295 and 0.125 g C 100 g −1 , respectively. To avoid misleading accounts of SOC stocks in agricultural soils, we recommend re-analysis of archived soil samples for SOC using high-temperature dry combustion methods. Where archived samples are not available, accounting for clay content improves conversion of LOI to SOC considerably. The use of the conventional conversion factor 0.58 is antiquated and provides misleading estimates of SOC stocks.
Show more

9 Read more

Converting loss-on-ignition to organic carbon content in arable topsoil: Pitfalls and proposed procedure

Converting loss-on-ignition to organic carbon content in arable topsoil: Pitfalls and proposed procedure

revisited the conversion of LOI to SOC. Data for temperate zone arable topsoils with different contents of SOC were collected from long-term agricultural field experiments with contrasting management at Askov (Denmark) and Rothamsted (UK), and from a texture gradient in an arable farmer’s field at Lerbjerg (Denmark) with uniform management and mineralogy. These fields had large ranges in LOI, SOC, clay and Fines20 making them rather representative for arable soils with respect to these properties. We also included clay-, silt- and sand-sized fractions isolated from Lerbjerg soils.
Show more

31 Read more

Converting loss-on-ignition to organic carbon content in arable topsoil: Pitfalls and proposed procedure

Converting loss-on-ignition to organic carbon content in arable topsoil: Pitfalls and proposed procedure

Summary Assessments of changes in soil organic carbon (SOC) stocks depend heavily on reliable values of SOC content obtained by automated high-temperature C analysers. However, historical as well as current research often relies on indirect SOC estimates such as loss-on-ignition (LOI). In this study, we revisit the conversion of LOI to SOC using soil from two long-term agricultural field experiments and one arable field with different contents of SOC, clay and particles < 20 μm (Fines20). Clay-, silt- and sand-sized fractions were isolated from the arable soil. Samples were analysed for texture, LOI (500 ∘ C for 4 hours) and SOC by dry combustion. For a topsoil with 2 g C and 30 g clay 100 g −1 soil, converting LOI to SOC by the conventional factor 0.58 overestimated the SOC stock by 45 Mg C ha −1 . The error increased with increasing contents of clay and Fines20. Converting LOI to SOC by a regression model underestimated the SOC stock by 5 Mg C ha −1 at small clay and Fines20 contents and overestimated the SOC stock by 8 Mg C ha −1 at large contents. This was due to losses of structural water from clay minerals. The best model to convert LOI to SOC incorporated clay content. Evaluating this model against an independent dataset gave a root mean square error and mean error of 0.295 and 0.125 g C 100 g −1 , respectively. To avoid misleading accounts of SOC stocks in agricultural soils, we recommend re-analysis of archived soil samples for SOC using high-temperature dry combustion methods. Where archived samples are not available, accounting for clay content improves conversion of LOI to SOC considerably. The use of the conventional conversion factor 0.58 is antiquated and provides misleading estimates of SOC stocks.
Show more

9 Read more

Determination of Extraction Efficiency of Different Solvents for Organic Carbon Content in Biomass Combustion Aerosols

Determination of Extraction Efficiency of Different Solvents for Organic Carbon Content in Biomass Combustion Aerosols

1 National Institute of Technology Warangal, Telangana, India 2 Bhabha Atomic Research Centre, Trombay, Mumbai, Maharashtra, India ABSTRACT Biomass combustion is a major source of organic carbon (OC) aerosols found in the atmosphere. In this study OC generated from biomass combustion was sampled and treated with different solvents to determine their extraction efficiency. Commonly used biomass fuels (wood and dung cake) were combusted in a temperature controlled chamber and the generated aerosols were sampled on Quartz filter paper. The dried filter paper pieces were analysed for their OC content in Total Carbon and Nitrogen Analyzer (PrimacsSNC, Skalar). From the obtained OC data extraction efficiencies were determined. The extraction process was repeated with four different solvents viz. deionised water, hexane, acetone and methanol. The extraction efficiency of each solvent was determined using difference in OC of filter paper before and after extraction. Extraction efficiency for OC samples obtained from wood combustion in water, hexane, acetone and methanol were 54, 30, 83 and 92 % respectively. And for dung cake, it is observed as 20, 37, 76 and 80 % respectively. The extraction efficiency depended on the polarity index of the solvent used.
Show more

5 Read more

Effect of leguminous crop and fertilization on soil organic carbon in 30 years field experiment

Effect of leguminous crop and fertilization on soil organic carbon in 30 years field experiment

Long-term field experiments offer the best practi- cal means to investigate the questions of sustainable crop production and a necessary tool for tracking changes in organic carbon content in the soil. In Europe, the most famous long-term experience with testing of different mineral and natural fertilizers and/or cultivation of various plant species was held at Rothamsted (England), Halle and Bad Laustädt (Germany), Prague-Ruzyně (Czech Republic) and Skierniewice (Poland) (Körschens 1996). The Institute of Soil Science and Plant Cultivation National Research Institute (IUNG-PIB) in Puławy is also involved in several kinds of long-term field studies, including soil organic carbon content monitoring, since 1979. A special trait of these experiments is that crop rotations included plants enriching and exhausting soil from humus, have been a permanent factor for the last 33 years.
Show more

5 Read more

Tillage effect on soil organic carbon, microbial biomass carbon and crop yield in spring wheat field pea rotation
 

Tillage effect on soil organic carbon, microbial biomass carbon and crop yield in spring wheat field pea rotation  

Yannong) rotation in the following sequence: 2013 spring wheat → 2014 field pea → 2015 spring wheat system; conventional tillage with stubble removed (T); no-till with stubble removed (NT); no-till with stubble retained (NTS) and conventional tillage with stubble incorporated (TS) were arranged in a randomised complete block design with three replicates. The seedbeds for conventional tillage practices were prepared by ploughing to a depth of 10–20 cm. Ploughing was carried out immediately after harvest of the previous crop. Harrowing was conducted prior to sowing in spring. In T plots, all stubbles were removed before ploughing, whereas in TS plots, all stubbles from the previous crop were returned to the original plots immediately after threshing and then incorporated into the soil with ploughing. No ploughing was performed throughout the season in the no-till system. The crops were sown with no-till seeder. In NT plots, all the stubbles were removed at crop harvest, whereas in NTS plots, all the stubbles from the previous crop were returned to the original plots on the soil surface without incorporation. Plots were 4 m wide × 17 m long in block 1, 21 m long in blocks 2 and 3 and 20 m long in block 4. This study was conducted on blocks 1, 2 and 4. Spring wheat was sown in mid-March at a rate of 187.5 kg/ha with a line spacing of 20 cm and harvested in late July to early- August. Field pea was sown in early April at a rate of 180 kg/ha with a line spacing of 24 cm and harvested in early July each year.
Show more

7 Read more

Effect of organic carbon content on the compactibility and penetration resistance of two soils formed from loess

Effect of organic carbon content on the compactibility and penetration resistance of two soils formed from loess

Each soil layer was compacted by 25 blows of a 2.5 kg hammer falling from 320 mm height. Soil bulk density and moisture were measured after the compaction. Bulk densities were plotted against the corresponding moisture content to obtain maximum bulk bulk density and critical moisture content. The penetration resistance of the compacted soil in the cylinder at the given moisture content and bulk density of soil was conducted using an INSTRON apparatus. Measurement of penetration resistance was carried out (in three replications per cylinder) with a probe 110 mm long, with a cone tip of 4.6 mm and a cone angle of 30°. For each cylinder with compacted soil was determined the mean value of penetration resistance at 20-60 mm depth since at that range of profile depth the results of the measurements were not affected by the surface conditions of the soil.
Show more

6 Read more

Show all 10000 documents...