Solod soils

A common critical limit for Zn deficiency in soils has been 0.5 mg/kg DTPA-extractable Zn for different crops (maize, wheat, and rice) (Sillanpaa, 1982). DTPA-extractable Zn concentration of 0.5-1.0 mg/kg has been marginal for sensitive crops (Sillanpaa, 1982). Brown isohumic calcareous soils of New South Wales in Australia with 35-60 mg/kg of total Zn showed Zn deficiency due to the low bioavailability of Zn. Zinc deficiency has been reported to occur in wheat on solidized solonetz and solodic soils and other calcareous soils of South Australia. Zinc application at the rate of 0.6-28 kg/ha to cereals, pastures, and maize of Australia has been reported (Reuter, 1975). Zn deficiency occurs in Turkey, India, Iraq, Mexico, and Pakistan (Table 7.8). Zinc deficiency is frequently observed in rice on calcareous paddy soils. 

It is somewhat surprising that so few Rn emanation power studies have been carried out on soils. The study by Delwiche (1958) on Rn release from "Great World Soil Groups" gives relative emanation powers for all but one soil. His results show clearly that the more highly weathered soils emanate more Rn and that the clay intervals emanate more than the silty and sandy intervals. Red podzolic, lateritic podzolic and solodic soils emanate the most and desert soils and western brown forest soils the least. Quantified emanation powers for soils and stream sediments are shown in Table 11-XII. 

The soil-forming rocks are mainly calcareous moraines, often covered with calcareous loess-like loams. The intense weathering ofprimary minerals and synthesis of secondary minerals have taken place. Solodized soils and solods occur in flat swamped lacustrine plains. They are present in large amounts in the Peace River basin. 

This region may be considered as an analog of the cold intra-continental Central Yakutian region of frozen-taiga solodized soils. But in the Canadian interior the climatic conditions are less severe than in Yakutia and there is no permanently frozen horizon in these soils. These insignificant differences are related to the biogeochemical turnover features as well Cb is equal to 10.0, Ct to 0.35 and Cbr to 3.5. 

Standley, J., Bruce, R. C., and Webb, A. A. (1990). A nutrient survey of legume evaluation sites on red earths, solodic soils and black earths in central Queensland. Trop. Grassl. 24 15-23. 

In vertisols on diorite, basalt, alluvions, and dolerite, total Mn is in the range of 1250-2750 mg/kg, while brown isohumic soils on calcareous sandstone and clayey sediments contain 550-1670 mg/kg Mn. Soils in the Adelaide and Southeast regions contain 140-1400 mg/kg total Mn. In solods on granitic rocks and alluvions, total Mn is 60-990 mg/kg. 

As indicated in Table 2, the distribution of nitrogen in the three soils formed under cool temperate climates is similar except that the Solod humic acid contains more amino acid nitrogen and the Chernozem humic acid more NH4 than do the other humic acids. In terms of proportions of nitrogen identified, the order is Solod humic acid > Chernozem humic acid > So-lonetz humic acid. Between 46 and 53% of the nitrogen in the humic acids is identified. 

Khan, S. U. and Schnitzer, M. (1972). Permanganate oxidation of humic acids, fulvic acids, and humins extracted from Ah horizons of a black chernozem, a black solod, and black solonetz soil. Can. J. Soil Sci. 52, 43-51. 

Solod. One of a group of soils that has been developed from saline materials. 

This is a zone of poorly drained alluvial-lacustrine plains, where features of continental salt accumulation are clearly expressed. Broad-Leafed Aspen Forest and Meadow Steppe ecosystems on Phaeozems and Chernozems with association with meadow-bog soils and Solods are characteristic of this region. 

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