A small rainfall simulator for the determination of soil erodibility.

A small rainfall simulator is described, which can be used in the field as well as in the laboratory for the determination of infiltration and erosion characterisitcs of soils. It is particularly suitable for soil conservation surveys, as it is light to carry and easy to handle in the field. A description is given of a standard procedure for the determination of topsoil erodibilities in the field and some results are presented. The method appears to be highly sensitive to soil properties influencing soil erodibility, such as clay content, organic matter content and soil pH. (Abstract retrieved from CAB Abstracts by CABI’s permission)

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Studies on the effect of clay and organic matter contents on the determination of cation exchange properties in clay soils by the ammonium acetate and methylene-blue methods

Agricultural and Food Science ◽

10.23986/afsci.71727 ◽

1969 ◽

Vol 41 (2) ◽

pp. 73-81

Author(s):

Raimo Erviö ◽

Osmo Mäkitie

Keyword(s):

Methylene Blue ◽

Organic Matter ◽

Ammonium Acetate ◽

Organic Matter Content ◽

Dye Adsorption ◽

Clay Content ◽

Matter Content ◽

Exchangeable Cations ◽

Adsorption Method

The correlation between CEC-values obtained by ammonium acetate and methylene-blue adsorption methods is relatively good (r = 0.86***). The latter method gives, however, about 30 per cent lower values for exchangeable cations. The extraction ratio used in the dye adsorption method has a clear effect on the level of the CEC-values. More complete adsorption was obtained with wider ratios. With increasing clay and humus contents the adsorption becomes more dependent on the soil-dye ratio. The effect of humus is more pronounced than that of clay. The CEC-values obtained by the ammonium acetate method were in better correlation to the clay content of soils than the values obtained by the dye-adsorption method, while the latter values were better correlated to the organic matter content of the soil. The percentages of exchangeable potassium, sodium and, especially, of magnesium, decrease when the clay content decreases, while that of calcium increases slightly. The ratio between exchangeable calcium and magnesium depends on the clay content of the soil ( r = 0.56***) so that the value of the ratio Ca:Mg increases when the clay content decreases (Table 1, q).

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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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Surfactant Effects on Picloram Adsorption by Soils

Weed Science ◽

10.1017/s0043174500062925 ◽

1976 ◽

Vol 24 (6) ◽

pp. 549-552 ◽

Cited By ~ 6

Author(s):

J. D. Gaynor ◽

V. V. Volk

Keyword(s):

Organic Matter ◽

Cationic Surfactant ◽

Anionic Surfactant ◽

Organic Matter Content ◽

Clay Content ◽

Surfactant Solution ◽

Matter Content ◽

Adsorption Sites ◽

Surfactant Solutions ◽

Extractable Al

The effects of soil organic matter, clay, extractable Al, cation exchange capacity, and pH on the adsorption of picloram (4-amino-3,5,6-trichloropicolinic acid) from aqueous and surfactant solutions were investigated. Linear adsorption isotherms for the soils were obtained with the Freundlich equation. Of the five soil properties investigated, Freundlich K values correlated with extractable Al and clay content. Picloram adsorption from aqueous solutions and from the non-ionic and anionic surfactant solutions was greater on the soils at pH 5 than at pH 7. The anionic surfactant competed with picloram for adsorption sites on the soils at pH 5. Picloram adsorption from solutions containing 0.1 and 1% cationic surfactant was greater than that from aqeuous and anionic and nonionic surfactant solutions. Picloram adsorption from the 10% cationic surfactant solution was similar on soils with pH 5 and 7 and increased with decreased organic matter content.

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Relationship of soil properties to fractionation, bioavailability and mobility of lead and zinc in soil

Plant Soil and Environment ◽

10.17221/2201-pse ◽

2008 ◽

Vol 53 (No. 5) ◽

pp. 225-238 ◽

Cited By ~ 28

Author(s):

N. Finžgar ◽

P. Tlustoš ◽

D. Leštan

Keyword(s):

Organic Matter ◽

Regression Analysis ◽

Soil Organic Matter ◽

Soil Properties ◽

Multiple Regression ◽

Contaminated Soils ◽

Organic Matter Content ◽

Clay Content ◽

Exchange Capacity ◽

Matter Content

Sequential extractions, metal uptake by Taraxacum officinale, Ruby’s physiologically based extraction test (PBET) and toxicity characteristic leaching procedure (TCLP), were used to assess the risk of Pb and Zn in contaminated soils, and to determine relationships among soil characteristics, heavy metals soil fractionation, bioavailability and leachability. Regression analysis using linear and 2nd order polynomial models indicated relationships between Pb and Zn contamination and soil properties, although of small significance (P < 0.05). Statistically highly significant correlations (P < 0.001) were obtained using multiple regression analysis. A correlation between soil cation exchange capacity (CEC) and soil organic matter and clay content was expected. The proportion of Pb in the PBET intestinal phase correlated with total soil Pb and Pb bound to soil oxides and the organic matter fraction. The leachable Pb, extracted with TCLP, correlated with the Pb bound to carbonates and soil organic matter content (R2 = 69%). No highly significant correlations (P < 0.001) for Zn with soil properties or Zn fractionation were obtained using multiple regression.

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Determination of Soil Nitrate and Organic Matter Content Using Portable, Filter-Based Mid-Infrared Spectroscopy

Proximal Soil Sensing ◽

10.1007/978-90-481-8859-8_12 ◽

2010 ◽

pp. 143-152 ◽

Cited By ~ 2

Author(s):

B.R. Jahn ◽

S.K. Upadhyaya

Keyword(s):

Organic Matter ◽

Infrared Spectroscopy ◽

Organic Matter Content ◽

Matter Content ◽

Soil Nitrate ◽

Mid Infrared ◽

Mid Infrared Spectroscopy

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Response of Fractal Analysis to Soil Quality Succession in Long-Term Compound Soil Improvement of Mu Us Sandy Land, China

Mathematical Problems in Engineering ◽

10.1155/2020/5463107 ◽

2020 ◽

Vol 2020 ◽

pp. 1-7

Author(s):

Haiou Zhang ◽

Jiancang Xie ◽

Jichang Han ◽

Haipeng Nan ◽

Zhen Guo

Keyword(s):

Organic Matter ◽

Sandy Soil ◽

Sustainable Use ◽

Organic Matter Content ◽

Soft Rock ◽

Clay Content ◽

Matter Content ◽

Practical Significance ◽

Sandy Land ◽

Mu Us Sandy Land

The degraded aeolian sandy soil in China’s Mu Us Sandy Land requires amendment before it can be suitable for maize or other agricultural production. The addition of material from the local “soft” bedrock can create a new compound soil whose particle composition and structural stability are key issues for sustainable soil development in the region. We used field data from 2010 to 2018 to study the variations in fractal characteristics of compound soil particles at soft rock to sand volume ratios of 1 : 1, 1 : 2, and 1 : 5, along with changes in soil organic matter. Over the study period, all three compound soils showed gradual increases in clay and silt content with corresponding decreasing sand content. The fractal dimension (FD) of particles at ratio 1 : 2 increased by 8.8%, higher than those at 1 : 1 (8.6%) and 1 : 5 (7.7%). The organic matter content (OMC) of particles at ratio 1 : 2 reached a maximum (6.24 ± 0.30 g/kg), an increase of 12 times over the original value. The FD and OMC of particles at ratios 1 : 1 and 1 : 5 were less stable but showed overall increase. The 1 : 2 ratio compound soil was most suitable for maize growth as its clear increase in silt and clay content most improved the texture and OMC of the original sandy soil. Such research has important theoretical and practical significance for understanding the evolutionary mechanism and sustainable use of the compound soil in agriculture within the Mu Us Sandy Land.

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Diversity and distribution of crustaceans from 13 sheltered sandy beaches along São Sebastião Channel, south-eastern Brazil

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315401004118 ◽

2001 ◽

Vol 81 (3) ◽

pp. 475-484 ◽

Cited By ~ 26

Author(s):

P.R. Nucci ◽

A. Turra ◽

E.H. Morgado

Keyword(s):

Organic Matter ◽

Organic Matter Content ◽

Clay Content ◽

Fine Sand ◽

Sandy Beaches ◽

Matter Content ◽

Sediment Grain Size ◽

Crustacean Species ◽

South Eastern ◽

Eastern Brazil

The crustacean species composition in the intertidal zones of 13 sheltered unconsolidated marine beaches in south-eastern Brazil is described. Fifty-three crustacean species were collected, adding 46 species to the total reported by previous studies in the same region. Decapods dominated the community, in contrast to exposed sandy beaches where peracarids normally predominate. The species were distributed irregularly among the beaches. Richness varied markedly among sites, and was positively related to a combination of factors such as fine sand grains, high organic matter content, and relatively low silt–clay content. The presence of rock fragments enabled both rocky shore and sandy beach crustaceans to occur on the same beaches. Richness and abundance of crustaceans showed no clear relationship to sediment grain size and slope, in contrast to the norm for exposed sandy beaches. The dominance of the tanaid Kalliapseudes schubarti in some areas may be a result of organic matter pollution in the region. These beaches showed higher species richness than typical sheltered and exposed sandy beaches, indicating that this sheltered, highly heterogeneous seascape is an important area for conservation.

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Effect of Different Factors on the Adsorption of Phosphamidon on Two Different Types of Indian Soil

Adsorption Science & Technology ◽

10.1177/026361749801600801 ◽

1998 ◽

Vol 16 (8) ◽

pp. 583-594 ◽

Cited By ~ 14

Author(s):

Dhirendra Singh

Keyword(s):

Organic Matter ◽

Adsorption Isotherms ◽

Alluvial Soil ◽

Organic Matter Content ◽

Clay Content ◽

Matter Content ◽

Natural Soil ◽

Standard Entropy ◽

Indian Soil ◽

Different Types

The effect of exchangeable cations (H+ and Na+). autoclaving, organic matter, anionic surfactants and temperature on the adsorption of phosphamidon on two different types of Indian soil was studied. The adsorption isotherms for all the effects/treatments were in close agreement with the Freundlich equation and yielded S-shaped isotherms. The amount of phosphamidon adsorbed in all cases was higher in medium black (silt loam) soil than alluvial soil (sandy loam) and was related to the organic matter content, clay content, CaCO3 content, surface area and cation-exchange capacity of the soils. The adsorption on both types of soil follows the order H+-soil > Na+-soil > natural soil at 10°C > natural soil at 20°C > autoclaved soil > organic matter-removed soil > anionic surfactant > natural soil at 40°C, which was in accordance with the Freundlich constant, KF, and distribution coefficient, Kd, values. The adsorption capacity of phosphamidon for organic matter and clay content for both the soils was evaluated by calculating the Kom and Kc values when it was found that phosphamidon adsorption was better correlated with the clay content than with the orgnic matter content on the basis of adsorption isotherms. Various thermodynamic parameters such as the thermodynamic equilibrium constant (K0), the standard free energy (ΔG0), the standard enthalpy (ΔH0) and the standard entropy (ΔS0) changes have been calculated as a means of predicting the nature of the isotherms.

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