MINERALOGICAL COMPOSITION OF SOME GREY WOODED SOILS DEVELOPED FROM GLACIAL TILL

1961 ◽  
Vol 41 (2) ◽  
pp. 228-240 ◽  
Author(s):  
S. Pawluk
Keyword(s):  
Mineralogical Composition ◽  
Fine Sand ◽  
Mineral Weathering ◽  
Glacial Till ◽  
Sand Fraction ◽  
Mineral Fraction ◽  
Layer Structures ◽  
Mineralogical Study ◽  
Similar Materials ◽  
Exchange Acidity

Grey Wooded profiles representing five soil series developed on glacial till in Alberta were studied. The clay mineral fraction in these soils was found to contain montmorillonite, illite, kaolinite and quartz. Authigenic chlorite and "mixed layer" structures were present in the soil sola. Examination of the fine sand fraction revealed the presence of quartz, potash-feldspars and soda-calcic feldspars in the light (sp. gr. < 2.70) mineral fraction with biotite, muscovite, chlorite and highly weathered amphiboles and pyroxenes comprising the intermediate (sp. gr. 2.70–2.96) mineral fraction. The heavy (sp. gr. > 2.96) mineral fraction contained primarily iron oxides, amphiboles, garnets and pyroxenes with a wide variety of other minerals in relatively low quantities.The mineralogical data presented suggest variations in weathering in the sola of the soils studied, despite their similar morphological features. Active and exchange acidity showed little relationship to the degree of mineral weathering. Weathering appeared to be more severe in horizons where acid conditions result from the presence of exchangeable hydrogen rather than where similar acid conditions result from exchangeable aluminium. The mineralogical study was found to be exceedingly valuable in distinguishing between morphologically similar materials of different lithology.

Exchange acidity of wheat and pea roots in salt solutions

1974 ◽  
Vol 41 (2) ◽  
pp. 403-413 ◽  
Author(s):  
Stig Ledin ◽  
Lambert Wiklander
Keyword(s):  
Salt Solutions ◽  
Pea Roots ◽  
Exchange Acidity

scholarly journals Risk of acidification of the organic shrimp model at Tam Giang commune, Nam Can district, Ca Mau province

2017 ◽  
Vol 1 (M1) ◽  
pp. 60-67
Author(s):  
Tho Nguyen ◽  
Khanh Nguyen Nha Dang ◽  
Tu Thi Kim Tran
Keyword(s):  
Organic Matter ◽  
Pond Water ◽  
Depth Range ◽  
Alkaline Ph ◽  
Wet Season ◽  
Pond Sediment ◽  
Decomposition Of Organic Matter ◽  
Mangrove Soils ◽  
Ph Range ◽  
Exchange Acidity

This paper assesses the risk of acidification of the organic shrimp model certified by Naturland at Tam Giang commune, Nam Can district, Camau province. Pond water and sediment was sampled in 8 ponds in March, July and November 2015, dike soil and mangrove soils were sampled in March 2015. Pond sediment and mangrove soils are highly reduced (Eh of top sediment and soils to 60 cm depth range respectively from -299 – -1mV and -321 – -52mV). Pond water ranges from neutral to slightly alkaline (pH of pond water 7.01-8.82) and sediment from slightly acidic to slightly alkaline (pH of fresh sediment 6.05-7.64, pHH2O 6.63-7.78, pHKCl 6.35-7.43). Mangrove soils show a large pH range with very low minimums (pHH2O 3.72, pHKCl 3.05), reconfirming the presence of pyrite mineral in the soil profile. Mangrove soils deposited on the dikes (partly oxidized) are very acidic (pHH2O 2.51±0.72, pHKCl 1.81-2.14, exchange acidity 11.56±2.69 meq/100g). At the start of the wet season, pH of pond water reduces sharply as a result of reception of acidic components from the oxidized pyritic material (FeS2) on the dikes. The exchange acidity in pond sediment and mangrove soils are negatively correlated with organic matter, indicating that the decomposition of organic matter under reduced conditions contributes to exchange acidity in pond environment. Risk of acidification of the organic shrimp model is high due to managerial activities (mostly channel digging and disposal of pyrite-containing mangrove soils on the dikes).

DEEP PLOWED SOLONETZIC AND CHERNOZEMIC SOILS: I. TILTH AND PHYSICOCHEMICAL FEATURES OF THE CULTIVATED LAYER

1985 ◽  
Vol 65 (4) ◽  
pp. 629-638 ◽  
Author(s):  
G. D. BUCKLAND ◽  
S. PAWLUK
Keyword(s):  
Physical Properties ◽  
Soil Properties ◽  
Soil Classification ◽  
Total N ◽  
East Central ◽  
Soil Fabric ◽  
Physicochemical Features ◽  
Moisture Stability ◽  
Deep Plowing ◽  
Exchange Acidity

Micromorphological, chemical, mineralogical and physical properties of deep plowed and conventionally tilled soils were evaluated at five sites in east-central Alberta. Soil properties, as they relate to soil classification and seedbed tilth, were determined. Deep plowing resulted in the development of a unique soil fabric in Ap horizons which, relative to conventionally tilled soils, had characteristics tending towards higher salinity, sodicity, pH, clay, smectite and strength and lower exchange acidity, total C, total N, available moisture, stability and plasticity. Landscapes dominated by Solonetzic soils responded differently to deep plowing than landscapes where significant areas of Chernozemic soils were present [Formula: see text]. Solonetzic landscapes tended towards significantly higher salinity, sodicity and strength in Ap horizons than Chernozemic landscapes. Key words: Tilth, deep plowing, soil classification, reclamation

The accumulation of soil organic matter under pasture and its effect on soil properties

1969 ◽  
Vol 9 (39) ◽  
pp. 437 ◽  
Author(s):  
NJ Barrow
Keyword(s):  
Organic Matter ◽  
Soil Nitrogen ◽  
Cation Exchange Capacity ◽  
Organic Phosphorus ◽  
Inorganic Phosphorus ◽  
Exchange Capacity ◽  
Buffering Capacity ◽  
Exchangeable Cations ◽  
Cent Increase ◽  
Exchange Acidity

Comparisons of paired virgin and pasture samples of Coolup sand showed that nitrogen had accumulated in the top 12.5 cm under pasture at an average of 24 p.p.m. per year. Carbon, sulphur, and organic phosphorus also accumulated to give C : N : S : P ratios of 118 : 10 : 1.2 : 0.47. The accumulation of sulphur accounted for about a quarter of the sulphur added in fertilizer and the accumulation of organic phosphorus accounted for about a tenth of the phosphorus added. Inorganic phosphorus had also accumulated but the amount varied between soils. The cation exchange capacity, as measured by summation of exchangeable cations and exchange acidity, increased by an average of 44 m-equiv. per g increase in nitrogen or 3.7 m-equiv. per g increase in carbon. Most of the increase was due to increases in exchange acidity. However, the buffering capacity of the soil for potassium was only slightly affected by the increase in organic matter. The water held by the soil between 0.1 bar and 15 bar suction increased by an average of 3.3 per cent per 0.1 per cent increase in soil nitrogen. When the soils were incubated the ratio of nitrogen mineralized to sulphur mineralized was large, especially when the incubation period was short. In the field there was a strong annual cycle of nitrogen and sulphur availability. Values were high in autumn, low in winter, and rose again at the end of spring.

scholarly journals Variability of some soil properties along a toposequence in a basaltic parent material of Vom, Plateau State Nigeria

2020 ◽  
pp. 77-81
Keyword(s):  
Spatial Variability ◽  
Soil Properties ◽  
Chemical Properties ◽  
Parent Material ◽  
High Variability ◽  
Available Phosphorus ◽  
Plateau State ◽  
Topographic Positions ◽  
Physical And Chemical ◽  
Exchange Acidity

Topography influences the distribution of some soil physical and chemical properties. This study assessed some variation in soil properties resulting from the topographic effect on Basaltic parent material at Vom Jos Plateau State in the Southern Guinea zone of Nigeria. Soil samples were collected at an interval of 20m and at depths of 0 to15cm and 15 to 30cm, parceled, labeled and taken to the laboratory for analysis of the selected for analysis. The results from the study revealed that variations in soil properties along the landscape segments were probably due to their positions toposequence characteristics in soils. Clay, silt and gravel contents varied moderately (CV = 22.9, 15.42 and 32.55% respectively), while sand did not vary much (CV = 8.47%). Organic carbon showed high variability (CV = 38.08%) while soil pH in (H2O and CaCl2) showed less spatial variability (with CV = 4.91 and 6.45% respectively). Available phosphorus has high variability (CV = 37.59%). Magnesium, K and Ca showed high spatial variability (CV = 42.60, 35.85, and 35.84% respectively), while Na and exchange acidity were moderately variable (CV = 24.39 and 24.27% respectively). Generally, some of the soil chemical properties were varied with topographic positions.

scholarly journals Aluminium and acidity in Finnish soils

1971 ◽  
Vol 43 (1) ◽  
pp. 11-19
Author(s):  
Armi Kaila
Keyword(s):  
Soil Ph ◽  
Mineral Soil ◽  
Sandy Soils ◽  
Soil Samples ◽  
Clay Soils ◽  
Organic Soils ◽  
Regression Equations ◽  
Organic C ◽  
Exchange Acidity ◽  
Soil Groups

In the present study an attempt was made to study by statistical methods the proportion of Al of the exchange acidity of 298 soil samples of various kind, and to what extent the titratable nonexchangeable acidity in these soils is connected with Al, when Al soluble in Tamm’s acid oxalate was used as its indicator. Unbuffered N KCI replaced Al only from soil samples with a pH less than 5.3 in 0.01 M CaCl2 . In this part of the material, Al corresponded, on the average, to one third of the exchange acidity of mineral soil samples, and to 16 per cent of that of organic soils. The amount of Al was usually the higher the lower the soil pH, but the correlation was close only in the group of clay soils. Titratable nonexchangeable acidity was estimated as the difference of the amount of acidity neutralized at pH 8.2 and the corresponding amount of exchange acidity replaced by unbuffered KCI. In 100 clay soil samples it was, on the average, 12.0 ± 1.3 me/100 g, in 42 samples of silt and loam soils 8.8 ± 1.8 me/100 g, in 99 sandy soils 8.9 ± 1.1 me/100 g and in 57 organic soils 49.1 ± 6.8 me/100 g. There was no correlation between titratable nonexchangeable acidity and the clay content within various soil groups. In the clay soils exalate soluble Al alone explained 78.3 %, in the silt and loam soils 59.8 %, in the sandy soils 6.5 %, and in the organic soils 0.6 % of the variation in titratable nonexchangeable acidity. Taking into account the content of organic C increased the rate of explanation only to 82.1 % in clay soils, to 84.1 % in silt and loam soils, to 83,1 % in sandy soils, and to 63.7 % in the organic soils. Further, adding the soil pH increased the rate of explanation 5.8 to 9.6 per cent units in various soil groups, but considering of oxalate soluble Fe did no more distinctly increase the part of variation explained, except in the organic soils. Regression equations were calculated for the relationship of these variables. According to the partial correlation coefficients and to the β-coefficients, the relative importance of oxalate soluble Al in explaining the variation in titratable nonexchangeable acidity was in the clay soils higher than even that of organic C content, but in the other mineral soil groups it was less important than both C content and pH; in the organic soils even oxalate soluble Fe appeared to be slightly more important.

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