LOSSES INHERENT IN IGNITION PROCEDURES FOR DETERMINING TOTAL ORGANIC PHOSPHORUS

1964 ◽  
Vol 44 (1) ◽  
pp. 1-6 ◽  
Author(s):  
J. F. Dormaar ◽  
G. R. Webster
Keyword(s):  
Complex Formation ◽  
Organic Phosphorus ◽  
Mineral Soil ◽  
Phosphate Esters ◽  
Organic Soils ◽  
Incomplete Combustion ◽  
Resistance To Oxidation

One mineral soil with known amounts of organically bound phosphorus added to it, two organic soils, and five known phosphate esters were ignited at various temperatures to study losses of phosphorus as a result of ignition.Incomplete recoveries of phosphorus were obtained from the mineral soil. For the organic soils incomplete combustion occurred at temperatures below 650 °C and volatilization at temperatures higher than 400 °C. Either complex formation or resistance to oxidation occurred in the case of RNA, phytin, and lecithin.

GHG mitigation potential of agricultural management practises on mineral and organic soils

2021 ◽  
Author(s):  
Saara Lind ◽  
Marja Maljanen ◽  
Merja Myllys ◽  
Mari Räty ◽  
Sanna Kykkänen ◽  
...  
Keyword(s):  
Greenhouse Gas ◽  
Agricultural Soils ◽  
Mineral Soil ◽  
Ghg Emissions ◽  
Grassland Management ◽  
Organic Soils ◽  
Carbon Dioxide Exchange ◽  
Ghg Mitigation ◽  
Nutrient Quality ◽  
Effect On Yield

<p>Agricultural soils are a significant source of greenhouse gas (GHG) emissions. To study these emissions, we are currently building three research platforms that consist of full eddy covariance instrumentation for determination of net ecosystem carbon dioxide exchange and fluxes of methane and nitrous oxide. These platforms will be completed with supporting weather, plant and soil data collection. Two of our platforms are sites on organic soils with a thick peat layer (>60 cm) and the third one is on a mineral soil (silt loam). To study the role of the grassland management practises at these sites, we have initiated ORMINURMI-project. Here, we will characterise the effects of ground water table (high vs. low), crop renewal methods (autumn vs. summer) and plant species (tall fescue vs. red glover grass) on greenhouse gas budgets of grass production. Also effect on yield amount and nutrient quality will be determined. In this presentation, we will present the preliminary data collected at these research platforms and our plans for the use of these data in the coming years.</p>

Development of calibration algorithms for selected water content reflectometry probes for burned and non-burned organic soils of Alaska

2010 ◽  
Vol 19 (7) ◽  
pp. 961 ◽  
Author(s):  
Laura L. Bourgeau-Chavez ◽  
Gordon C. Garwood ◽  
Kevin Riordan ◽  
Benjamin W. Koziol ◽  
James Slawski
Keyword(s):  
Soil Moisture ◽  
Moisture Content ◽  
Water Content ◽  
Soil Profile ◽  
Soil Moisture Content ◽  
Mineral Soil ◽  
Organic Soil ◽  
Organic Content ◽  
Organic Soils ◽  
Probe Type

Water content reflectometry is a method used by many commercial manufacturers of affordable sensors to electronically estimate soil moisture content. Field‐deployable and handheld water content reflectometry probes were used in a variety of organic soil‐profile types in Alaska. These probes were calibrated using 65 organic soil samples harvested from these burned and unburned, primarily moss‐dominated sites in the boreal forest. Probe output was compared with gravimetrically measured volumetric moisture content, to produce calibration algorithms for surface‐down‐inserted handheld probes in specific soil‐profile types, as well as field‐deployable horizontally inserted probes in specific organic soil horizons. General organic algorithms for each probe type were also developed. Calibrations are statistically compared to determine their suitability. The resulting calibrations showed good agreement with in situ validation and varied from the default mineral‐soil‐based calibrations by 20% or more. These results are of particular interest to researchers measuring soil moisture content with water content reflectometry probes in soils with high organic content.

Equilibrium and kinetic approaches for modelling sorption processes on radiocesium soil profiles in Fukushima prefecture

2020 ◽  
Author(s):  
Hamza Chaif ◽  
Frederic Coppin ◽  
Aya Bahi ◽  
Laurent Garcia-Sanchez
Keyword(s):  
Soil Contamination ◽  
Residence Time ◽  
Nuclear Power ◽  
Mineral Soil ◽  
Soil Surface ◽  
Organic Soils ◽  
Organic Layer ◽  
Soil Profiles ◽  
Sorption Model ◽  
Slow Evolution

<p>The study of radionuclides (RNs) retention processes onto the solid phases is a key element for the prediction of their transfer in soils. It allows a better quantification of the persistence of radioactive contaminants on the soil surface, their availability for root uptake and their vertical transfer towards groundwater.</p><p>This work addresses the comparison between equilibrium and kinetic hypotheses of sorption processes on real post-accidental soil contamination profiles. The equilibrium-kinetic (EK) sorption model was selected as a non-equilibrium parameterization embedding the K<sub>d</sub> approach. It supposes the existence of two types of sorption sites. The first sites are at equilibrium with solution, whereas for the second sites, kinetics of the sorption and desorption are taken into consideration.</p><p>We focused our study on four <sup>137</sup>Cs soil contamination profiles measured in a cedar stand 35 km northwest of the Fukushima Dai-ichi Nuclear Power Plant. Profiles were sampled at four different dates (between 2013 and 2018) by measuring <sup>137</sup>Cs activity in both organic (humus + litter layer) and mineral soil layers reaching a maximum depth of 20cm.</p><p>To successfully simulate the <sup>137</sup>Cs transfer throughout these soil profiles, the input flux at the mineral soil surface was reconstructed from monitored throughfall, stemflow and litterfall fluxes in the same forest stand from July 2011 to November 2016 crossed with initial deposit and dynamic of the organic layer activity.</p><p>The EK model reproduced the measured contamination profiles slightly better than the fitted K<sub>d</sub> model. While both models were able to reproduce the overall vertical distribution throughout the profiles, the persistent contamination at the surface was closer to the measured value with the EK approach. Additionally, the fitted K<sub>d</sub> parameters (2000 L/kg to 6500 L/kg depending on the parcel) were considerably higher than the recommended value by The IAEA for organic soils (270 L/kg). When used, this recommended K<sub>d</sub> value produced profiles with considerably faster transfer rate between layers and shorter persistence of the contamination at the surface.</p><p>To further distinguish the models behaviors, long term simulations were conducted. EK hypotheses induced much longer residence time of the contamination at the soil surface. For instance, by 2030, the EK approach predicted that 75 % of the contamination still remained in the 0-2 cm layer due to the slow desorption rate, whereas the K<sub>d</sub> approach predicted it to be around 51 %. This fraction becomes even smaller (8 %) when using the K<sub>d</sub> value (270 L/kg) recommended by the IAEA for organic soils.</p><p>These results prove that the choice of the sorption model is critical in post-accidental situations. An equilibrium approach, especially when using recommended parameter values, can result in an underestimation of the RNs residence time in the surface. Whereas a kinetic approach, by distinguishing different sorption and desorption rates, is able to reproduce the slow evolution of <sup>137</sup>Cs soil profiles with time that is already observed in the case of Chernobyl contaminated areas 30 years after the accident.</p>

scholarly journals Utilization of organic soils in Puerto Rico

1969 ◽  
Vol 35 (2) ◽  
pp. 57-65
Author(s):  
M. A. Lugo López ◽  
J. A. Bonnet
Keyword(s):  
Puerto Rico ◽  
Mineral Soil ◽  
Point Of View ◽  
Organic Soils ◽  
Available Phosphorus ◽  
Physical Point ◽  
Precise Knowledge ◽  
Total Acreage ◽  
Phosphorus And Potassium ◽  
Management And Conservation

There are more than 25,000 acres of organic soils in Puerto Rico, of which approximately 10 percent are under cultivation. They occupy very low topographical positions and in many instances brackish waters affect the profile. They were formed from the accumulation of leaves, twigs, roots, and other materials in lagoons and bays. The characteristic vegetation consists primarily of mangroves associated with other hydrophylic plants. Tiburones muck and Saladar muck make up more than 50 percent of the total acreage of Puerto Rican organic soils. These soils are generally well supplied with humus and nitrogen. Although they seem to be well supplied with calcium, and available phosphorus and potassium, it should be remembered that they contain smaller total amounts of these nutrients than the average mineral soil, because of their lighter weight per unit volume. From the physical point of view they seem to be well adapted to cultivation and rather easy to handle, if a sound program of management and conservation is followed. In cultivated areas yields of 45 tons of ratoon cane per acre have been obtained under the local management methods of the region, without a precise knowledge of the properties of organic soils, which probably require more specialized techniques to attain maximum yields and higher quality crops. The total cost of draining the marshes, where practicable, as well as of getting rid of the harmful salts, if present, will be high, but its beneficial effect on the economy of Puerto Rico can be far reaching.

scholarly journals Carrot Yield, Quality, and Storability in Relation to Preplant and Residual Nitrogen on Mineral and Organic Soils

2006 ◽  
Vol 16 (2) ◽  
pp. 286-293 ◽  
Author(s):  
Sean M. Westerveld ◽  
Mary Ruth McDonald ◽  
Alan W. McKeown
Keyword(s):  
Mineral Soil ◽  
Organic Soil ◽  
Application Rate ◽  
Yield Response ◽  
Organic Soils ◽  
Residual Soil ◽  
N Application ◽  
Application Rates ◽  
Yield Quality ◽  
N Management

The Nutrient Management Act (NMA) established in the province of Ontario in 2002 has prompted a re-evaluation of nitrogen (N) management practices. However, N management research in Ontario is currently outdated. The experiment in this 3-year study was designed to establish the yield response of carrot (Daucus carota) to N fertilization on mineral and organic soils and identify the relative yield effects of preplant and residual soil N. In 2002, N was applied at 0%, 50%, 100%, 150%, and 200% of recommended N application rates in Ontario as ammonium nitrate (organic soil: 60 kg·ha-1 preplant; mineral soil: 110 kg·ha-1 split 66% preplant/33% sidedress). Experimental units were split in half in 2003 and 2004, and N was applied to one half in 2003 and both halves in 2004 to identify the effects of residual N from the previous season on yield. Crop stand, yield, and quality were assessed at harvest, and storability was assessed by placing carrots into cold storage for 6 months. Nitrogen application rate had no effect on the yield, quality, or storability of carrots grown on organic soil. On mineral soil there were no effects of applied N in the first year of the 3-year study. In the second and third year on mineral soil, yield increased in response to increasing N, up to 200% and 91% of the recommended application rate, respectively, based on the regression equations. Yield declined above 91% of the recommended application rate in the third year due to a decrease in stand at higher N application rates. There were no effects of N on carrot quality or storability on mineral soil. On mineral soil, residual N from the 2002 season had more effect on yield at harvest in 2003 than N applied in 2003. This major effect of residual soil N on yield provides an explanation for the lack of yield response to preplant N application in previous studies conducted in temperate regions. These results indicate that there is no single N recommendation that is appropriate for all years on mineral soil. Assessing the availability of N from the soil at different depths at seeding is recommended to determine the need for N application.

scholarly journals Data of hydraulic properties of North East and Central German soils

2010 ◽  
Vol 3 (1) ◽  
pp. 131-142 ◽  
Author(s):  
U. Schindler ◽  
L. Müller
Keyword(s):  
Bulk Density ◽  
Data Base ◽  
Mineral Soil ◽  
Organic Matter Content ◽  
Water Retention Curve ◽  
Organic Soils ◽  
Soil Water Retention Curve ◽  
Soil Water Retention ◽  
North East ◽  
Wide Range

Abstract. The paper presents a data base of soil hydrological properties of North East and Central German soils. Included are measured data of the soil water retention curve and the unsaturated hydraulic conductivity function. Information to geo reference, soil type and horizon are given. Additional soil physical data like particle size distribution, dry bulk density, organic matter content and other variables are presented and its measurement is methodically described. The data base includes original measurement results of 278 organic and of 497 mineral soil samples from 103 sites. The mineral soils cover a wide range of texture classes and dry bulk densities. The organic soils and samples vary in dependence on the degree of decomposition and mineralization, the dry bulk density and the total porosity.

scholarly journals Organic Matter Causes Chemical Pollutant Dissipation Along With Adsorption and Microbial Degradation

2021 ◽  
Vol 9 ◽  
Author(s):  
A. Vilhelmiina Harju ◽  
Ilkka Närhi ◽  
Marja Mattsson ◽  
Kaisa Kerminen ◽  
Merja H. Kontro
Keyword(s):  
Organic Matter ◽  
Microbial Degradation ◽  
Mineral Soil ◽  
Organic Soil ◽  
Organic Soils ◽  
First Response ◽  
Chemical Pollutant ◽  
Mineral Soils ◽  
Soil And Sediment

Views on the entry of organic pollutants into the organic matter (OM) decaying process are divergent, and in part poorly understood. To clarify these interactions, pesticide dissipation was monitored in organic and mineral soils not adapted to contaminants for 241 days; in groundwater sediment slurries adapted to pesticides for 399 days; and in their sterilized counterparts with and without peat (5%) or compost-peat-sand (CPS, 15%) mixture addition. The results showed that simazine, atrazine and terbuthylazine (not sediment slurries) were chemically dissipated in the organic soil, and peat or CPS-amended soils and sediment slurries, but not in the mineral soil or sediment slurries. Hexazinone was chemically dissipated best in the peat amended mineral soil and sediment slurries. In contrast, dichlobenil chemically dissipated in the mineral soil and sediment slurries. The dissipation product 2,6-dichlorobenzamide (BAM) concentrations were lowest in the mineral soil, while dissipation was generally poor regardless of plant-derived OM, only algal agar enhanced its chemical dissipation. Based on sterilized counterparts, only terbutryn appeared to be microbially degraded in the organic soil, i.e., chemical dissipation of pesticides would appear to be utmost important, and could be the first response in the natural cleansing capacity of the environment, during which microbial degradation evolves. Consistent with compound-specific dissipation in the mineral or organic environments, long-term concentrations of pentachloroaniline and hexachlorobenzene were lowest in the mineral-rich soils, while concentrations of dichlorodiphenyltrichloroethane (DTT) and metabolites were lowest in the organic soils of old market gardens. OM amendments changed pesticide dissipation in the mineral soil towards that observed in the organic soil; that is OM accelerated, slowed down or stopped dissipation.

scholarly journals Príspevok k problematike určovania špecifickej hmotnosti subhorizontov opadu lesných pôd

2013 ◽  
Vol 59 (1) ◽  
pp. 38-43
Author(s):  
Jana Bútorová
Keyword(s):  
Mineral Soil ◽  
Soil Aggregate ◽  
Soil Samples ◽  
Organic Soils ◽  
Laboratory Methods ◽  
Elementary Unit ◽  
Final Density ◽  
International Laboratory ◽  
Mineral Soils

Abstract According to national and international laboratory methods, the density of soil samples is determined by pycnometer in heated samples crushed by ultrasound. In mineral soils, the elementary unit of density is represented by a mineral grain of quartz, granite, andesite, etc. On the other hand, in organic soils, the elementary unit is represented by a leaf (or just a part of it), needles, stems and roots. Heating of the mineral grain causes its release from the soil aggregate. Organic parts of the soil are losing air vacuoles by heat treatment while in the same time, carbohydrates, proteins, oils and resins create new chemicals which are heavier than water. That is a reason why density determination of litter subhorizons in forest soils needs to have different rules in comparison with mineral soil samples. Samples with more than 50 volume per cent of organic matter are not treated by heat and do not decompose. In case of high mineral soil content, mineral parts are removed from the sample and their density is determined. The final density is based on mathematically processed data.

scholarly journals High CO<sub>2</sub> fluxes from grassland on histic Gleysol along soil carbon and drainage gradients

2014 ◽  
Vol 11 (3) ◽  
pp. 749-761 ◽  
Author(s):  
K. Leiber-Sauheitl ◽  
R. Fuß ◽  
C. Voigt ◽  
A. Freibauer
Keyword(s):  
Organic Carbon ◽  
Water Table ◽  
Ecosystem Respiration ◽  
Mineral Soil ◽  
Ghg Emissions ◽  
Organic Soils ◽  
Organic Carbon Content ◽  
Peat Layer ◽  
Organic Carbon Concentration ◽  
High Organic Carbon Content

Abstract. Drained organic soils are anthropogenic emission hotspots of greenhouse gases (GHGs). Most studies have focused on deep peat soils and on peats with high organic carbon content. In contrast, histic Gleysols are characterized by shallow peat layers, which are left over from peat cutting activities or by peat mixed with mineral soil. It is unknown whether they emit less GHGs than deep Histosols when drained. We present the annual carbon and GHG balance of grasslands for six sites on nutrient-poor histic Gleysols with a shallow (30 cm) histic horizon or mixed with mineral soil in Northern Germany (soil organic carbon concentration (Corg) from 9 to 52%). The net GHG balance, corrected for carbon export by harvest, was around 4 t CO2–C–eq ha−1 yr−1 on soils with peat layer and little drainage (mean annual water table < 20 cm below surface). The net GHG balance reached 7–9 t CO2–C–eq ha−1 yr−1 on soils with sand mixed into the peat layer and water tables between 14 cm and 39 cm below surface. GHG emissions from drained histic Gleysols (i) were as high as those from deep Histosols, (ii) increase linearly from shallow to deeper drainage, (iii) but are not affected by Corg content of the histic horizon. Ecosystem respiration (Reco) was linearly correlated with water table level even if it was below the histic horizon. The Reco/GPP ratio was 1.5 at all sites, so that we ruled out a major influence of the inter-site variability in vegetation composition on annual net ecosystem exchange (NEE). The IPCC definition of organic soils includes shallow histic topsoil, unlike most national and international definitions of Histosols. Our study confirms that this broader definition is appropriate considering anthropogenic GHG emissions from drained organic soils. Countries currently apply soil maps in national GHG inventories which are likely not to include histic Gleysols. The land area with GHG emission hotspots due to drainage is likely to be much higher than anticipated. Deeply drained histic Gleysols are GHG hotspots that have so far been neglected or underestimated. Peat mixing with sand does not mitigate GHG emissions. Our study implies that rewetting organic soils, including histic Gleysols, has a much higher relevance for GHG mitigation strategies than currently recognized.

OXYGEN FLUX MEASUREMENTS IN ORGANIC SOIL

1980 ◽  
Vol 60 (4) ◽  
pp. 641-650 ◽  
Author(s):  
JAMES A. CAMPBELL
Keyword(s):  
Applied Voltage ◽  
Mineral Soil ◽  
Organic Soil ◽  
Oxygen Flux ◽  
Organic Soils ◽  
Wide Range ◽  
Effective Voltage ◽  
Flux Measurements ◽  
Mineral Soils ◽  
Almost All

Many measurements of oxygen flux in mineral soils have been reported; however, few such measurements have been made in organic soil. Almost all reported measurements of oxygen flux are at constant applied voltage, despite criticism of this technique, possibly due to the complexity of existing techniques for measuring oxygen flux at effective voltage. Equipment suitable for measuring oxygen flux at applied and effective voltage in organic soil was designed, and simplified techniques were developed and tested. As reported for mineral soils, soil resistance is relatively constant spatially and with depth in individual soils. Limited poisoning of the platinum electrode surface occurred after long periods of time and, contrary to previous assumptions, cannot be detected by erratic readings. Unlike mineral soil, the amperage-voltage slopes are constant over a wide range of organic soils, simplifying the technique for estimating oxygen flux at constant effective volatage. Comparison of simultaneous measurements of oxygen flux at constant and effective voltage indicates that oxygen flux measurements at effective voltage were twice those at applied voltage and strongly correlated (r2 = 0.96, n = 22).

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