On the question of exchange acidity in soils and the relation between titration acidity and actual acidity

Soil Science ◽  
1926 ◽  
Vol 22 (3) ◽  
pp. 215
Author(s):  
&NA;
Keyword(s):  
Actual Acidity ◽  
Exchange Acidity ◽  
Titration Acidity

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.

The measurement of actual acidity in acid sulfate soils and the determination of sulfidic acidity in suspension after peroxide oxidation

Soil Research ◽  
2002 ◽  
Vol 40 (7) ◽  
pp. 1133 ◽  
Author(s):  
Angus E. McElnea ◽  
Col R. Ahern ◽  
Neal W. Menzies
Keyword(s):  
Regression Line ◽  
Correction Factors ◽  
Acid Sulfate Soils ◽  
Peroxide Oxidation ◽  
Acid Sulfate ◽  
Inorganic Sulfur ◽  
Actual Acidity ◽  
Sulfate Soils ◽  
The Relationship

Improvements to the routine methods for the determination of actual acidity in suspension for acid sulfate soils (ASS) are introduced. The titratable sulfidic acidity (TSA) results using an improved peroxide-based method were compared with the theoretical acidity predicted by the chromium reducible sulfur method for 9 acid sulfate soils. The regression between these 2 measures of sulfidic acidity was highly significant, the slope of the regression line not significantly different from unity (P = 0.05) and the intercept not significantly different from zero. This contrasts with results of other workers using earlier peroxide oxidation methods, where TSA substantially underestimated the theoretical acidity predicted by reduced inorganic sulfur analysis. Comparison was made between the 2 principal measurements from the improved peroxide method (TSA and SPOS), with SPOS converted to theoretical sulfidic acidity to allow comparison. The relationship between these 2 measurements was highly significant. The effects of titration in suspension, as well as raising titration end points to pH 6.5, were investigated, principally with respect to the titratable actual acidity (TAA) result. TAA results obtained by KCl extraction were compared with those obtained using BaCl2, MgCl2, and water extraction. TAA in 1 M KCl suspensions titrated to pH 6.5 agreed well with titratable actual acidity measured using the 25-h extraction approach of the Lin et al. (2000a) BaCl2 method. Both BaCl2 and KCl solutions were ineffective at fully recovering acidity from synthetic jarosite without repeated extraction and titration. The application of correction factors for the estimation of total actual acidity in ASS is not supported by the results of this investigation. Acid sulfate soils that contain substantial quantities of jarosite or other acid-producing but relatively insoluble sulfate minerals continue to prove problematic to chemically analyse; however, an approach for estimating this component is discussed.

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 Environmental evaluation of suitability of recultivated land in a manganese quarry for the existence of soil biota

2017 ◽  
Vol 25 (4) ◽  
Author(s):  
I. М. Loza ◽  
V. I. Chiorna
Keyword(s):  
Biological Diversity ◽  
Soil Biota ◽  
Natural Ecosystems ◽  
Natural Habitats ◽  
Ecological Functions ◽  
Environmental Evaluation ◽  
Bulk Layer ◽  
Environmental Properties ◽  
Reclaimed Soil ◽  
Actual Acidity

The challenge of degradation of natural ecosystems because of human activity is considered by the world community to be the most serious problems facing mankind. As a result of mineral extraction, man-made landscapes and environmentally ruined areas replace natural habitats and agroecosystems; a whole spectrum of man-made processes are typical for such landscapes, which leads to a decrease in species richness and biological diversity within such areas. Degraded territories formed in the process of coal mining are often partially restored through remediation measures. During the implementation of the technical stage of remediation, substrates with different potential fertility having different environmental properties and quality are used. However, in quality assessment of remediated soils insufficient attention is paid to restoration of the environmental properties of the soils, namely their suitability for the existence of soil biota, which ensures the soil’s sustainability and vitality. The main indicators determining the productivity of remediated lands and the degree of their suitability for the existence of soil biota are values of actual acidity and degree of salinity. An assessment of the quality of reclaimed lands of  the Ordzhonikidzevsky ore mining and processing enterprise was carried out on the example of the Zaporizhsky open-cast mine with the aim of assessing the possibility of their economic use and suitability for the existence of soil biota , as well as to make recommendations for further rational use. It was found that  main characteristics  of the study area (capacity of bulk humic layer, content of humus in the bulk layer, content of physical clay in the bulk humic layer and in the subsoil, average soil density in the meter bulk layer, salinity of the bulk humic layer and subsoil, composition and properties of subsoil), of the Zaporizhzhya quarry's reclamation is suitable for the further settlement and successful existence of the soil biota. It is concluded that as a result of the technical stage of reclamation, an artificial reclaimed soil was obtained, which according to its characteristics is similar to the primary zonal soils that were located in this area prior to mining; the recultivated soil has somewhat lower fertility and greater salinity at the lower horizons, but is capable of performing ecological functions and can not only be used for economic purposes, but also perform ecological functions, serving as an environment for the existence of soil biota.

scholarly journals The effects of sample fat value manipulation on raw cow milk composition and indicators

2011 ◽  
Vol 59 (1) ◽  
pp. 101-112 ◽  
Author(s):  
Oto Hanuš ◽  
Marcela Vyletělová ◽  
Martin Tomáška ◽  
Eva Samková ◽  
Václava Genčurová ◽  
...  
Keyword(s):  
Somatic Cell Count ◽  
Crude Protein ◽  
Freezing Point ◽  
Milk Composition ◽  
Cow Milk ◽  
Freezing Point Depression ◽  
Sampling Errors ◽  
Milk Samples ◽  
Actual Acidity ◽  
The Impact

Values of milk indicators (MIs) can be influenced by sampling errors and milk manipulation. This paper estimated the freezing point depression (FPD) and other MIs drifts which can cause fat movement. That is important for: – preparation of reference milk samples (MSs) for proficiency testing and instrument calibrations; – estimation of the impact of milk treatment as centrifugation in dairy plants on FPD. Five MSs (A = original milk; milk with modified fat (F) content; B = less F, C = low F, D = more F, E = high F) were created (gravitation F separation at 4 °C for 12 hours) with the same milk matrix 12× per year. F averages increased by 4.80% (122.1%) from 1.68 to 6.48% due to manipulation. It increased variability of MIs especially for SNF (solids non fat), L (lactose) and CP (crude protein). SCC (somatic cell count) averages increased by 803 (196.8%) from 9 to 812 thousand.ml−1. Correlation (r) F × SCC was 0.85 (P < 0.001). SNF, L and CP averages decreased by 0.47% (5.3%), 0.31% (6.3%) and 0.17% (5.0%). Correlations were −0.78, −0.75 and −0.64 (P < 0.001). Urea decreased along with F increase by 1.05 mg.100ml−1 (2.9%) but with r −0.13 (P > 0.05). Acetone increased by 1.37 mg.l−1 (47.6%) with r 0.21 (P > 0.05). Electrical conductivity decreased by 0.23 mS.cm−1 (6.0%) with r −0.15 (P > 0.05). Alcohol stability was reduced by 0.14 ml (23.3%) with r −0.15 (P > 0.05). FPD, titration and actual acidity were not influenced.

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).

scholarly journals APPLICATION OF LACTIC ACID IN PRESERVATION OF NINH THUAN GREEN GRAPES NH01-48

2018 ◽  
Vol 55 (5A) ◽  
pp. 116
Author(s):  
Nguyen Thi Hanh
Keyword(s):  
Lactic Acid ◽  
Acid Treatment ◽  
Dry Matter ◽  
Physicochemical Characteristics ◽  
Bacterial Strains ◽  
Acid Pretreatment ◽  
Yeast Strains ◽  
Plastic Bags ◽  
Preservation Technology ◽  
Titration Acidity

Ninh Thuan green grapes NH01-48 is popularly cultured in Ninh Thuan province. However, due to the lack of preservation technology and/or facility, Ninh Thuan grapes are transported to and consumed in other areas of the country in a limited volume. This study aimed to assess application of lactic acid in treatment of Ninh Thuan grapes for preservation. Effect of lactic acid on grapes with or without challenging microorganisms was examined. Green grapes NH01-48 was washed with sterile water, and then dried on air. Grapes were challenged with a cocktail of microorganisms previously isolated from Ninh Thuan grapes, including four bacterial strains (Bacillus cereus, Pseudomonas oryzihabitans, Citrobacter sp., and Flavobacterium sp.), three yeast strains (Wickerhamomces anomalus, Hanseniaspora opuntiae, Debaryomyces nepalensis) and one fungus Penicillium sp. at 5 × 104 CFU/ml. Then grapes were treated with 3 % lactic acid solution for 5 min (soaking) prior to be packed in plastic bags with punched hole of         3 mm diameter, distance between holes is 3 cm and preserved in refrigeration condition at                 4 ± 0.5 oC. Grapes without challenging microorganisms/without acid pretreatment/without challenging microorganisms but treated with acid were used for comparison. Samples were taken every 5th day until 30 days. Color, hardness, total dry matter, titration acidity, and total microorganism count were measured. Results showed that when applied treatment of lactic acid on grape with and without challenging microorganisms, the change in grapes’ hardness, color, dry matter and titration acidity was minimized, demonstrating positive activity of lactic acid on grape physicochemical characteristics. Samples without lactic acid treatment were spoiled after 15-20 days of preservation, whereas the ones with acid treatment can be last for at least 30 days. Moreover, number of total microorganisms count after 30 days of preservation were acceptable in samples with lactic acid treatment (ca. 103 CFU/g). Therefore, lactic acid can be potential for application in grapes preservation. The combined effect with other preservation techniques needs to be further studied.

Oxidation rate of pyrite in acid sulfate soils: in situ measurements and modelling

Soil Research ◽  
2004 ◽  
Vol 42 (6) ◽  
pp. 499 ◽  
Author(s):  
F. J. Cook ◽  
S. K. Dobos ◽  
G. D. Carlin ◽  
G. E. Millar
Keyword(s):  
Oxidation Rate ◽  
Volume Ratio ◽  
Soil Surface ◽  
Biological Processes ◽  
Acid Sulfate Soils ◽  
Acid Sulfate ◽  
The Difference ◽  
Actual Acidity ◽  
Sulfate Soils

The generation of acidity from oxidation of pyrite in acid sulfate soils requires the transport of oxygen into the soil profile. The sink for this oxygen will not only be the chemical reaction with pyrite but the biological processes associated with both microbial and plant respiration. The biological sinks in burning the oxygen (O2) will release CO2. The respiratory quotient which is the molar volume ratio of O2 : CO2 varies between 1.3 and 0.7 depending on the source of the organic matter being oxidised, but is generally 1.0. The oxidation of pyrite by oxygen will, by comparison with the biological processes, produce minor amounts of CO2 (if any) by reaction with intrinsic carbonate minerals. Gas samplers were installed into the soil at various depths and samples collected from these at approximately fortnightly intervals. The samples were analysed by gas chromatography and the CO2 and O2 profiles obtained. The flux of these gases was calculated and the difference between these attributed to the oxidation of pyrite. The flux difference varied over the period of sampling and on average gave an in situ oxidation rate of 11.5 tonnes H2SO4/ha.year. This is considerably more that the rate of export of acidity from this site and would explain the considerable actual acidity storage in these soils. A model is developed for steady state transport of oxygen into soils with an exponentially decreasing biological sink with depth and an exponentially increasing chemical (pyrite) sink with depth. The model is developed in non-dimensional variables, which allows the relative strengths and rates of increase or decrease in sink terms to be explored. This model does not explicitly treat the flow of oxygen in macropores. Other models that do explicitly calculate macropore flow are compared and found to give similar results. These results suggest that the use of biological or other sinks near the soil surface could be a useful method for reducing the oxidation rate of pyrite in acid sulfate soils.

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