CHANGES IN MICROMORPHOMETRIC PARAMETERS OF VOIDS ALONG THE PROFILE OF ZONAL SOILS IN EUROPEAN RUSSIA

The soils are distinguished by the presence and the profile distribution pattern of such pedogenic parameters as the organic matter content, available pedofeatures, structural state of the soil mass, etc. They differ in the organization of the pore space throughout the soil profile as well. Under discussion are results of computer micromorphometric analysis of fine macropores d = 0.2-2.0 mm in thin sections of vertical orientation from samples taken in genetic horizons of podzolic, soddy podzolic, gray forest soils and chernozems at the territory of European Russia. The profile changes in voids were analyzed using the most informative morphometric parameters such as the total area of the studied voids in thin sections, the content of fissure-like voids and those of vertical and/or horizontal orientation. The soil types under study showed differences in profile distribution of the above parameters. By analogy with the profile of carbonates, salts, organic matter it is proposed to recognize diagnostic profiles of the pore space represented as a system of voids in genetic horizons of the soil profile. Empiric profiles of the pore space reveal a great diversity. The most complicated organization of the pore space is inherent to soddy podzolic soils, the most simple “smoothed” profiles are characteristic of typical chernozems. The expert qualitative typization showed that the eluvial-illuvial and accumulative-eluvial-illuvial types are dominant among the studied empiric profiles of the pore space (42 and 30% respectively), what is explained by prevailing texture-differentiated soils. On the other hand, it makes possible to use the profile of the pore space as a diagnostic parameter of soils and soil formation processes.

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Factors Affecting Microbial Formation of Nitrate-Nitrogen in Soil and Their Effects on Fertilizer Nitrogen Use Efficiency

The Scientific World JOURNAL ◽

10.1100/tsw.2001.308 ◽

2001 ◽

Vol 1 ◽

pp. 122-129 ◽

Cited By ~ 7

Author(s):

Alan Olness ◽

Dian Lopez ◽

David Archer ◽

Jason Cordes ◽

Colin Sweeney ◽

...

Keyword(s):

Organic Matter ◽

Decision Aid ◽

Pore Space ◽

Organic Matter Content ◽

Clay Content ◽

Matter Content ◽

N Fertilizer ◽

Nitrate N ◽

Soil Clay ◽

Soil Clay Content

Mineralization of soil organic matter is governed by predictable factors with nitrate-N as the end product. Crop production interrupts the natural balance, accelerates mineralization of N, and elevates levels of nitrate-N in soil. Six factors determine nitrate-N levels in soils: soil clay content, bulk density, organic matter content, pH, temperature, and rainfall. Maximal rates of N mineralization require an optimal level of air-filled pore space. Optimal air-filled pore space depends on soil clay content, soil organic matter content, soil bulk density, and rainfall. Pore space is partitioned into water- and air-filled space. A maximal rate of nitrate formation occurs at a pH of 6.7 and rather modest mineralization rates occur at pH 5.0 and 8.0. Predictions of the soil nitrate-N concentrations with a relative precision of 1 to 4 μg N g–1of soil were obtained with a computerized N fertilizer decision aid. Grain yields obtained using the N fertilizer decision aid were not measurably different from those using adjacent farmer practices, but N fertilizer use was reduced by >10%. Predicting mineralization in this manner allows optimal N applications to be determined for site-specific soil and weather conditions.

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Parameter Selection for the Evaluation of Compost Quality

Agronomy ◽

10.3390/agronomy10101567 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1567

Author(s):

Haydee Peña ◽

Heysa Mendoza ◽

Fernando Diánez ◽

Mila Santos

Keyword(s):

Electrical Conductivity ◽

Organic Matter ◽

Pore Space ◽

Linear Regression Analysis ◽

Organic Matter Content ◽

Principal Component ◽

Primary Component ◽

Matter Content ◽

Germination Index ◽

Soil Restoration

This work studies variables measured from the first phase of composting through the acquisition of the final product, with the goal of identifying those that are more strongly related to quality and are most useful for developing an index. The necessity to establish quality control procedures thus exists for the classification of raw materials in the same way as for the finished products. To accomplish this, three mixtures were prepared, with the goal of achieving a C/N ratio of 30 and a moisture content of 60%. The primary component of each mixture was: fruit processing waste (C1), sewage sludge from the food industry (C2), and the manufacturing waste of fried foods (C3). Temperatures were measured over 107 days, with the corresponding data fit to a logistical model where T °C ~ α / ((1 + exp (− (Time − β) / − γ))) + δ, with interaction compost * time being statistically significant (p < 0.001). This allowed for the temperatures, in keeping with health concerns, to be confirmed. Likewise, a linear regression analysis demonstrated the decomposition of organic matter at 0.82%/week. Statistically, the parameters, measured during the process, with the least variability were selected, which differed in the average contrasts: germination index (cucumber), electrical conductivity, and average moisture. A principal component analysis (PCA) and Spearman’s correlation analysis revealed the best Germination Index (GI) values for C1, due to lower electrical conductivity (EC) and bulk density (Bd) along with higher organic matter content (TOM). For its part, C2 induced a higher Relative emergence (RE) of the cucumber thanks to its higher content of total nitrogen (TN) and lower contribution of Cu, Zn and K. C3 showed a higher presence of salts, less favorable physical characteristics (>Bd and <TPS, total pore space) and higher content of Zn and Cu. Composting carried out with appropriate mixtures can offer high-quality products for use as fertiliser, in soil restoration, and as an alternative substrate to peat and virgin mountain soil.

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

International Agrophysics ◽

10.1515/intag-2015-0075 ◽

2016 ◽

Vol 30 (1) ◽

pp. 19-23 ◽

Cited By ~ 4

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.

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Erratum to: Relationship among soil management, organic matter content and root development along the explorable soil profile in the vineyard

BIO Web of Conferences ◽

10.1051/bioconf/20191304022 ◽

2019 ◽

Vol 13 ◽

pp. 04022

Author(s):

Alberto Vercesi ◽

Matteo Gatti ◽

Claudia Meisina ◽

Massimiliano Bordoni ◽

Michael Maerker ◽

...

Keyword(s):

Organic Matter ◽

Root Development ◽

Soil Profile ◽

Organic Matter Content ◽

Soil Management ◽

Matter Content

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EFFECTS OF ROOT PLANTS AND LITTER ON SOIL MACROPOROSITY, INFILTATION RATE AND EROSION

Jurnal Sains dan Teknologi Mitigasi Bencana ◽

10.29122/jstmb.v16i1.4873 ◽

2021 ◽

Vol 16 (1) ◽

pp. 17-22

Author(s):

Hanggari Sittadewi

Keyword(s):

Organic Matter ◽

Soil Profile ◽

Water Storage ◽

Organic Matter Content ◽

Infiltration Rate ◽

Matter Content ◽

Plant Roots ◽

Soil Infiltration ◽

Runoff Water ◽

High Infiltration

Plant roots and litter produced by tree that grow have an important role in the entry of rainwater into the soil (infiltration) as water storage in the future. The effects of plant roots and litter on increasing infiltration rate is due to increased soil macroporosity. The presence of roots that spread in various layers in the soil profile will further increase the organic matter content of the soil and loosen the soil thereby increasing soil macroporosity. In addition, dead roots will form empty spaces that can be filled by infiltration water, as well as active roots that have gaps between roots and soil that can be filled infiltration water. The high infiltration rate will reduce the amount of excessive runoff water so as to reduce the occurrence of erosion.

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Soil organic matter and aggregates affected by wildfire in a Pinus halepensis forest in a Mediterranean environment

International Journal of Wildland Fire ◽

10.1071/wf02020 ◽

2002 ◽

Vol 11 (2) ◽

pp. 107 ◽

Cited By ~ 59

Author(s):

J. Mataix-Solera ◽

I. Gómez ◽

J. Navarro-Pedreño ◽

C. Guerrero ◽

R. Moral

Keyword(s):

Electron Microscopy ◽

Organic Matter ◽

Soil Organic Matter ◽

Forest Fire ◽

Soil Profile ◽

Soil Structure ◽

Organic Matter Content ◽

Matter Content ◽

Crown Fire ◽

Surface Fire

Three Mediterranean soils located in the north of the Province of Alicante (Spain) were studied for a year after a forest fire. The percentage of water-stable aggregates (between 0.2 and 4 mm) and organic matter content were measured. Microaggregates (< 0.2 mm) were observed using electron microscopy. The results showed the importance of type of forest fire on soil organic matter and aggregates. Soil structure was more affected by surface fire (which affects mainly brushwood and soil surface) than crown fire (which burns the tops of trees and some brushwood). Accumulation of organic matter from burnt trees and brushwood in areas affected by crown fire and alterations in organic matter content through the soil profile were observed. Surface forest fire affected soil structure more negatively than crown fire as observed using electron microscopy. Soils affected by surface fire may be more easily eroded and recovery of vegetation may be delayed because of effects on soil structure. Organic matter content through the soil profile comparing burnt and adjacent unburnt soil could be used to determine the type of fire.

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The effect of organic matter on the structure of clay soils.

Netherlands Journal of Agricultural Science ◽

10.18174/njas.v11i4.17541 ◽

1963 ◽

Vol 11 (4) ◽

pp. 250-263 ◽

Cited By ~ 2

Author(s):

P. Boekel

Keyword(s):

Organic Matter ◽

Soil Structure ◽

Pore Space ◽

Farmyard Manure ◽

Organic Matter Content ◽

Matter Content ◽

Actual Structure ◽

Air Content ◽

Micro Particles ◽

Graphical Data

Tabular and graphical data show the effect of organic-matter levels (1-7%) on intrinsic soil structure (lower & upper plastic limit, moisture content atpF2) & actual soil structure (pore space, air content), & on the effect of organic manuring (farmyard manure, town refuse, green manure, ley) on structural properties. An increase in organic-matter content decreased the slaking sensitivity of soils, increased resistance to plastic deformation caused by mechanical forces on heavy clays under wet conditions, & improved actual structure by 0.6-0.7 points (visual estimation) for each per-cent organic matter. Lowest organic-matter content, providing good resistance to mechanical breakdown & giving proper structure for good plant growth, was required on a clay soil in which the 16 micro particles ranged between 15 & 30%, depending on soil treatment. (Abstract retrieved from CAB Abstracts by CABI’s permission)

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Relationship between petrographic parameters and physical-mechanical properties of weakly cemented sandstones

Quarterly Journal of Engineering Geology and Hydrogeology ◽

10.1144/qjegh2018-168 ◽

2020 ◽

Vol 54 (1) ◽

pp. qjegh2018-168

Author(s):

Zhenkang Wang ◽

Jiangfeng Chen ◽

Wenping Li ◽

Qiqing Wang ◽

Qinghe Niu ◽

...

Keyword(s):

Organic Matter ◽

Multiple Regression ◽

Organic Matter Content ◽

Textural Properties ◽

Matter Content ◽

P Wave ◽

Stepwise Multiple Regression ◽

Regression Equations ◽

Overburden Pressure ◽

Thin Sections

Petrographic characteristics (textural properties and modal compositions) have an intrinsic influence on the physical and mechanical (PM) properties of weakly cemented sandstones. Sixteen sandstone samples were tested to determine the PM parameters and then thin sections from those samples were used to measure the petrographic parameters. Petrographic parameters were analysed statistically to establish quantitative relationships between the petrographic characteristics and PM properties. Based on multiple linear regression (MLRA) and stepwise multiple regression analyses (SMRA), several multiple regression equations with significant petrographic variables were established for estimating the PM parameters of the sandstone. Results indicated that uniaxial compressive strength (UCS) and Young's modulus (E) were closely related to mean grain size (Mz) (φ-value), non-uniform coefficient (Cu), fractal dimension (Fd), Riley sphericity (Ψp), packing proximity (Pp), floating contacts (Fl), grain-to-grain contacts (G-G), feldspar content and organic matter content. An increased percentage of grain-to-cement contacts (G-C) and reduced percentages of grain-to-matrix contacts (G-M) and organic matter content indicated a high value of Poisson's ratio (POISS). In addition, Mz, Cu, Fd, Ψp, quartz, feldspar, and organic matter contents were found to be significant parameters for density and P-wave velocity (Vp). Furthermore, density and POISS could be predicted using the results from the MLRA and Fd was a good predictor for density, Vp and UCS using the results from the SMRA. Additionally, it was noted that the petrographic characteristics of roof sandstones had significant influence on the overburden pressure characteristics within the coal faces in the Shendong mining area.

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The Effect of Harvesting Activities on Soil Compaction, Root Damage, and Suckering in Colorado Aspen

Western Journal of Applied Forestry ◽

10.1093/wjaf/8.2.62 ◽

1993 ◽

Vol 8 (2) ◽

pp. 62-66 ◽

Cited By ~ 26

Author(s):

Wayne D. Shepperd

Keyword(s):

Organic Matter ◽

Soil Profile ◽

Soil Compaction ◽

Fine Roots ◽

Mineral Soil ◽

Organic Matter Content ◽

Matter Content ◽

Saturated Soils ◽

Soil Conditions ◽

Root Damage

Abstract Logging activities cause significant compaction on skid trails in commercial aspen harvest areas. Bulk density increases have persisted up to 12 yr following harvest. Compaction of the upper 0.2 m of an undisturbed mineral soil profile increased with each succeeding pass of a tractor where later passes contributed less to the total compaction effect. Compaction effects were similar under wet soil conditions. High organic matter content in the upper mineral soil profile may have decreased the magnitude of compaction effects. Root damage can occur without apparent disruption of the soil profile, especially to fine roots and those in saturated soils. West. J. Appl. For. 8(2):62-66.

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Porosity and hydrocarbon composition evolution in shales from the Domanic and Bazhenov Formations: Insights from pyrolysis and aqua thermolysis experiments.

10.5194/egusphere-egu2020-17423 ◽

2020 ◽

Author(s):

Dina Gafurova ◽

Anton Kalmykov ◽

Dmitriy Korost ◽

Tikhonova Margarita ◽

Vidishcheva Olesia

Keyword(s):

Organic Matter ◽

Pore Space ◽

Experimental Studies ◽

Organic Matter Content ◽

Hydrocarbon Composition ◽

Structural Features ◽

Space Structure ◽

Matter Content ◽

Source Rocks ◽

Reservoir Conditions

The Domanic and Bazhenov Formations are the largest unconventional oil and gas resources in Russia. In this regard, research of mechanisms and transformation features of pore space structure, as well as hydrocarbon fluids composition are of greatest interest. In recent time technologies for modeling of thermal maturation of rocks under close to reservoir conditions similar, such as pyrolysis and aqua pyrolysis can be used. The natural process of organic matter maturation has a direct impact on the rock pore space alterations. Experimental studies of rocks (more than 100 experiments) with monitoring of the pore space using computer microtomography were performed. As a result of research, it was possible to clarify the influence of rock characteristics on the transformation of the pore space, as well as on the hydrocarbons composition. The structural features of the mineral part of the rock control the distribution of organic matter: for rocks with a layered distribution of organic matter, the formation of a crack system is characteristic. In samples with a massive structure, newly formed pores were noted. The rocks with the highest organic matter content from 20% were characterized by the formation of lenses (Fig. 1). The content of organic matter and its maturity directly affect the volume of the newly formed pore space.Performed investigations allowed to reveal the trends of hydrocarbons generation in source rocks and unconventional reservoirs formation. Also heating of rocks by various methods under reservoir conditions approved potential of tertiary methods of reservoir stimulation. Pyrolysis in-situ of Bazhenov and Domanic source rocks would allow to generate &#8220;synthetic&#8221; oil of similar to natural one composition and increase permeability of rocks by pores and cracks formation.This work was partially (fully) supported by RFBR grant 18-35-20036.

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