EVALUATION OF METHODS FOR DETERMINATION OF TOTAL ORGANIC PHOSPHORUS IN CHERNOZEMIC SOILS OF SOUTHERN ALBERTA

1964 ◽  
Vol 44 (3) ◽  
pp. 265-271 ◽  
Author(s):  
J. F. Dormaar
Keyword(s):  
Phosphorus Content ◽  
Organic Phosphorus ◽  
Black Soil ◽  
Parent Material ◽  
Soil Series ◽  
Soil Zone ◽  
Southern Alberta ◽  
Qualitative Work ◽  
Evaluation Of Methods

Two Orthic Chernozemic profiles of each of four parent materials were selected at undisturbed sites within the Brown, Dark Brown, and Thin Black soil zones of southern Alberta. This constituted 24 profiles representing 12 Chernozemic soil series. Material from the Ah and Bm horizons was subjected to nine procedures for estimating total organic phosphorus.The data of this study generally substantiated the usefulness of a modified Kaila–Virtanen method for these soils. With some soils, such as those from the Brown soil zone and those developed from aeolian parent material, other methods gave similar results. Reproducible results were obtained with only four methods.The efficiency of estimation of some of the methods decreased as organic phosphorus content of the soil increased. This, together with several other observations, suggests that the organic phosphorus of soils cannot be measured quantitatively at present. Several of the comparisons between methods, however, will be useful for further qualitative work.

scholarly journals FRACTIONATION OF THE HUMUS OF SOME CHERNOZEMIC SOILS OF SOUTHERN ALBERTA

1964 ◽  
Vol 44 (2) ◽  
pp. 232-236 ◽  
Author(s):  
J. F. Dormaar
Keyword(s):  
Humic Acid ◽  
Carbon Content ◽  
Black Soil ◽  
Parent Material ◽  
Glacial Till ◽  
Total Carbon ◽  
Total Carbon Content ◽  
Parent Materials ◽  
Southern Alberta ◽  
Alcohol Benzene

Two orthic profiles, widely separated geographically, of each of four parent materials—lacustrine, alluvial–lacustrine, glacial till, and Aeolian—were selected at undisturbed sites within each of the Brown, Dark Brown, and Thin Black soil zones. Material from the Ah and Bm horizons was subjected to solvent extraction, and for each sample the total organic carbon of seven different fractions was determined.The efficiency of the procedure in extracting humus carbon decreased as the total carbon content of the soil increased. Total organic matter, the first humic acid fraction, and the combined total of the three humic acid fractions showed significant differences between soil zones. The only significant separation between all four parent materials was made by the alcohol-benzene fraction. Other parent material separations were possible only following the summation of data of several fractions, such as the three humic acid fractions or the two fulvic acid fractions. A simplification of the procedure in case of soils of one Order and a modification to overcome the impeding effect of increased carbon content are requisite.

scholarly journals Determination of organic phosphorus in samples of peat soils

1955 ◽  
Vol 27 (1) ◽  
pp. 104-115
Author(s):  
Armi Kaila ◽  
Oili Virtanen
Keyword(s):  
Sulphuric Acid ◽  
Room Temperature ◽  
Phosphorus Content ◽  
Organic Phosphorus ◽  
Peat Soil ◽  
Acid Extraction ◽  
Peat Soils ◽  
Alkali Extraction ◽  
Mineral Soils

Attention was paid in the present paper to the fact that the precision of the values obtained by different methods for the total organic phosphorus in soil cannot be very high. Even the variation caused by the treatment of the extracts and connected with the colorimetric estimation of phosphate in the solution makes it impossible to report the results more accurately than by 10—20 ppm organic P, at least if routine analyses are in question. Although the somewhat modified methods of Dean, Wrenshall and Dyer,. Pearson, and Mehta et al. yielded equal results for the organic phosphorus content of the respective mineral soils and of most of the peat soils analyzed, the treatment with cold alkali in the Wrenshall and Dyer procedure apparently failed to extract the organic phosphorus from two peat samples as quantitatively as the treatment with hot alkali in the other methods. On the basis of this observations a new modification of the method of Wrenshall and Dyer was proposed. It consists of an extraction of 1-g sample with 25 ml of 4 N sulphuric acid at room temperature for 18 hours, followed by washing with water and two successive extractions with 100 ml of 0.5 N sodium hydroxide, the first of them for 18 hours at room temperature, the second for 4 hours at 90°C. This method was found to extract from 40 peat soil samples on the average about 97 per cent of the total phosphorus dissolved by the Kjeldahl digestion and about 9 per cent more organic phosphorus than the method of Pearson. Experiments concerning the ignition and acid extraction procedures indicated that the method of Ghani was not suitable for the determination of organic phosphorus in the twelve samples analysed. The extraction with sulphuric acid showed no marked differences between the increase in the soluble phosphorus due to the ignition when the ratio of extraction was varied from 1:40 to 1:200, and the extractant from 0.2 N acid to 5 N acid. The results obtained for 40 peat samples by ignition for one hour at 600°C and extraction of the ignited and untreated samples with 0.2 N sulphuric acid in a ratio of 1:100 for half an hour were on the average 8 per cent higher than those given by the proposed acid-alkali extraction. The total organic phosphorus content of soil may probably be somewhat higher than the figure yielded by the acid-alkali extraction and slightly lower than the value obtained by the ignition method. For the present, the most reliable result seems to be found in the average of the data given by these two methods.

Chernozemic soils of Canada: Genesis, distribution, and classification

2011 ◽  
Vol 91 (5) ◽  
pp. 719-747 ◽  
Author(s):  
Dan Pennock ◽  
Angela Bedard-Haughn ◽  
Valerie Viaud
Keyword(s):  
Organic Compounds ◽  
Management Practices ◽  
Soil Formation ◽  
Black Soil ◽  
Parent Material ◽  
Soil Zone ◽  
Native Grasslands ◽  
Below Ground ◽  
Annual Water ◽  
Complex Organic

Pennock, D., Bedard-Haughn, A. and Viaud, V. 2011. Chernozemic soils of Canada: Genesis, distribution, and classification. Can. J. Soil Sci. 91: 719–747. Chernozemic soils in Canada have a characteristic biomantle that fully expresses the effect of organisms on soil formation. Additions of large amounts of below-ground biomass from grasses are transformed into complex organic compounds through the activities of meso- and macro-fauna, microbial degradation and combustion by fires. Degradation is regulated by (a) climatic influences on plant inputs and microbial activity, (b) the chemical and biochemical nature of the residues, (c) encapsulation of organic matter within aggregates by soil micro-faunal activities and freeze–thaw processes and (d) protection against decomposition by Ca2+ and clay minerals. These organic compounds are mixed with the mineral matrix through the action of organisms from mites to badgers. Regional differences in the regulators cause differences in soil organic carbon (SOC) storage and the colour value of the surface Chernozemic A horizon. The storage of SOC is lowest in the Brown soil zone (≈60 to 80 Mg ha−1) and greatest in the Black soil zone (≈120 to 150 Mg ha−1); this corresponds to a decrease in the annual water deficit from ≈200 mm (Brown) to 70 to 100 mm (Black). Where soil CaCO3 contents are high either through initial concentration in the parent material or by the precipitation of secondary CaCO3, substantially higher SOC storage than the regional norms can result. A repetitive catenary pattern occurs throughout the region. The primary controls on this pattern are hydrological – a lateral component to water flow in hillslopes leads to more developed horizonation downslope, and discharge surrounding wetlands causes precipitation of secondary carbonate minerals and more soluble salts in a fringe surrounding the wetlands. Chernozemic landscapes have been highly altered by humans through their conversion to agricultural production. Loss of the dense root network of the native grasslands causes a substantial decrease in SOC. This loss of carbon and reduction in A horizon thickness is accelerated by erosion; the effects of tillage erosion are now recognized as being ubiquitous through the agricultural region. The substantial amounts of SOC storage and our ability to increase storage through altered management practices make these soils a particular focus of interest in a future made more uncertain by the possibility of human-induced climatic change.

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