scholarly journals Calculating Sediment Compaction for Radiocarbon Dating of Intertidal Sediments

Radiocarbon ◽  
2004 ◽  
Vol 46 (1) ◽  
pp. 421-435 ◽  
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.

PERSISTENCE OF CHANGES IN SELECTED SOIL CHEMICAL AND PHYSICAL PROPERTIES AFTER PIPELINE INSTALLATION IN SOLONETZIC NATIVE RANGELAND

1987 ◽  
Vol 67 (4) ◽  
pp. 747-763 ◽  
Author(s):  
M. A. NAETH ◽  
A. W. BAILEY ◽  
W. B. McGILL
Keyword(s):  
Organic Matter ◽  
Physical Properties ◽  
Bulk Density ◽  
Organic Matter Content ◽  
Matter Content ◽  
Chemical Changes ◽  
Ecosystem Responses ◽  
Native Prairie ◽  
Natural Gas Pipelines ◽  
Mixed Prairie

A study was conducted in Solonetzic mixed prairie of southern Alberta to evaluate and determine the longevity of selected ecosystem responses to pipeline installation. Five adjacent natural gas pipelines on a series of rights-of-way (ROW) were studied at three sites. The lines, which were installed in 1957, 1963, 1968, 1972 and 1981, had diameters of 86, 86, 91, 107 and 107 cm, respectively. Soils were analyzed for particle size distribution, bulk density, pH, electrical conductivity, ion composition, and organic matter content. It was concluded that pipeline construction in Solonetzic mixed prairie range-land initially tended to improve surface soil chemical and physical properties compared to blowouts, but reduced soil quality in vegetated native prairie. Surface bulk density increased to 1.3–1.6 Mg m−3 from an undisturbed density of 0.9–1.0 Mg m−3. Increased densities were evident to 55 cm in all 1981 transects except the trench where subsurface densities were reduced. Chemical changes were associated with reduced organic matter and increased salts at the surface. On the basis of differences between the various ages of pipelines (1981, youngest; 1957, oldest) there was evidence for greater amelioration of chemical changes than of physical disturbances over time. The time needed to restore half the lost organic matter was estimated to be approximately 50 y. Key words: Pipeline, Solonetzic soil, rangeland (native), soil chemistry, bulk density, reclamation

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

Soil Research ◽  
1998 ◽  
Vol 36 (4) ◽  
pp. 655 ◽  
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.

Evaluating the Integral Suspension Pressure method for measuring the particle size distribution in soils with high organic matter content

2020 ◽  
Author(s):  
Cristina Contreras ◽  
Sara Acevedo ◽  
Sofía Martínez ◽  
Carlos Bonilla
Keyword(s):  
Particle Size ◽  
Organic Matter ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Soil Analysis ◽  
Organic Matter Content ◽  
Matter Content ◽  
New Methodologies ◽  
Pre Treatment ◽  
Standard Techniques

<p>Typical information in soil databases is the soil texture and particle size distribution. These properties are used for soil description or predicting other soil properties such as bulk density or hydraulic conductivity. Measuring particle size distribution with standards methods such as the pipette or hydrometer is time-consuming because of the sample pre-treatment used to remove organic matter or iron and the sample post-treatment. Nowadays, there are new methodologies for determining soil particle size distribution, such as the Integral Suspension Pressure (ISP) method, which measures the silt content in a semi-automatized process. Thus, the main objective of this study was to evaluate the suitability of the ISP method compared to standard techniques used in soil analysis and evaluate the effect of organic matter content in the ISP measurements. The main results showed that the ISP method is equivalent in accuracy to the pipette, especially for soils rich in silt or sand content. Also, the results demonstrate the convenience of removing the soil organic matter when using the ISP for soils with more than 1.5% organic matter.</p>

WITHIN-PEDON VARIABILITY IN SOIL PROPERTIES

1982 ◽  
Vol 62 (4) ◽  
pp. 631-639 ◽  
Author(s):  
G. T. PATTERSON ◽  
G. J. WALL
Keyword(s):  
Particle Size ◽  
Organic Matter ◽  
Calcium Carbonate ◽  
Particle Size Distribution ◽  
Soil Properties ◽  
Size Distribution ◽  
Organic Matter Content ◽  
Matter Content ◽  
Soil Drainage ◽  
Soil Material

Replicate soil samples (2–20) from the A, B and C horizons of 41 pedons were collected to measure within-pedon variability of particle size distribution, organic matter content, calcium carbonate equivalent and pH. Variability in soil properties was examined in relation to the mode of origin of the soil material, soil horizonation and soil drainage. Variance in particle size distribution was significantly influenced by mode of deposition as well as by soil horizons, while soil drainage had no significant influence on the variation in particle size distribution. Variance in calcium carbonate equivalent and organic matter content was not influenced by soil drainage or mode of deposition. The number of replicate samples required for statistically reliable evaluation of a pedon at given confidence limits was determined for the soil properties studied. The results of these calculations indicate the need for up to five replicate samples to achieve satisfactory levels of accuracy at the 95% confidence level for some of the soil properties studied.

scholarly journals Bulk Density Prediction for Histosols and Soil Horizons with High Organic Matter Content

2017 ◽  
Vol 41 (0) ◽  
Author(s):  
Sidinei Julio Beutler ◽  
Marcos Gervasio Pereira ◽  
Wagner de Souza Tassinari ◽  
Michele Duarte de Menezes ◽  
Gustavo Souza Valladares ◽  
...  
Keyword(s):  
Organic Matter ◽  
Bulk Density ◽  
Organic Matter Content ◽  
Matter Content ◽  
Soil Horizons ◽  
High Organic Matter Content ◽  
Density Prediction ◽  
High Organic Matter

scholarly journals Estimation of the density of the clay-organic complex in soil

2016 ◽  
Vol 30 (1) ◽  
pp. 19-23 ◽  
Author(s):  
Ewa A. Czyż ◽  
Anthony R. Dexter
Keyword(s):  
Organic Matter ◽  
Bulk Density ◽  
Pore Space ◽  
Organic Matter Content ◽  
Soil Bulk Density ◽  
Matter Content ◽  
Gas Content ◽  
Effective Density ◽  
Organic Complex ◽  
Arable Soils

Abstract Soil bulk density was investigated as a function of soil contents of clay and organic matter in arable agricultural soils at a range of locations. The contents of clay and organic matter were used in an algorithmic procedure to calculate the amounts of clay-organic complex in the soils. Values of soil bulk density as a function of soil organic matter content were used to estimate the amount of pore space occupied by unit amount of complex. These estimations show that the effective density of the clay-organic matter complex is very low with a mean value of 0.17 ± 0.04 g ml−1 in arable soils. This value is much smaller than the soil bulk density and smaller than any of the other components of the soil considered separately (with the exception of the gas content). This low value suggests that the clay-soil complex has an extremely porous and open structure. When the complex is considered as a separate phase in soil, it can account for the observed reduction of bulk density with increasing content of organic matter.

scholarly journals The impact of landscape evolution on soil physics: evolution of soil physical and hydraulic properties along two chronosequences of proglacial moraines

2020 ◽  
Vol 12 (4) ◽  
pp. 3189-3204
Author(s):  
Anne Hartmann ◽  
Markus Weiler ◽  
Theresa Blume
Keyword(s):  
Organic Matter ◽  
Physical Properties ◽  
Soil Properties ◽  
Bulk Density ◽  
Hydraulic Properties ◽  
Organic Matter Content ◽  
Soil Physical Properties ◽  
Matter Content ◽  
Data Set ◽  
Soil Chronosequence

Abstract. Soil physical properties highly influence soil hydraulic properties, which define the soil hydraulic behavior. Thus, changes within these properties affect water flow paths and the soil water and matter balance. Most often these soil physical properties are assumed to be constant in time, and little is known about their natural evolution. Therefore, we studied the evolution of physical and hydraulic soil properties along two soil chronosequences in proglacial forefields in the Central Alps, Switzerland: one soil chronosequence developed on silicate and the other on calcareous parent material. Each soil chronosequence consisted of four moraines with the ages of 30, 160, 3000, and 10 000 years at the silicate forefield and 110, 160, 4900, and 13 500 years at the calcareous forefield. We investigated bulk density, porosity, loss on ignition, and hydraulic properties in the form of retention curves and hydraulic conductivity curves as well as the content of clay, silt, sand, and gravel. Samples were taken at three depths (10, 30, 50 cm) at six sampling sites at each moraine. Soil physical and hydraulic properties changed considerably over the chronosequence. Particle size distribution showed a pronounced reduction in sand content and an increase in silt and clay content over time at both sites. Bulk density decreased, and porosity increased during the first 10 millennia of soil development. The trend was equally present at both parent materials, but the reduction in sand and increase in silt content were more pronounced at the calcareous site. The organic matter content increased, which was especially pronounced in the topsoil at the silicate site. With the change in physical soil properties and organic matter content, the hydraulic soil properties changed from fast-draining coarse-textured soils to slow-draining soils with high water-holding capacity, which was also more pronounced in the topsoil at the silicate site. The data set presented in this paper is available at the online repository of the German Research Center for Geosciences (GFZ; Hartmann et al., 2020b). The data set can be accessed via the DOI https://doi.org/10.5880/GFZ.4.4.2020.004.

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