Comparative Characteristics of Gypsum Morphotypesin Irrigated and Non-irrigated Calcaric Gypsisols and Methodological Aspects of Their Study // Eurasian Soil Science, 2026, Vol. 59:7 Pp. 21-36статьяПеревод
Статья опубликована в журнале из списка Web of Science и/или Scopus
Аннотация:Gypsum morphotypes were studied in nonirrigated and irrigated gypsiferous soils of the Dzhezkazgan Botanical Garden (Ulytau oblast, Republic of Kazakhstan). The profiles of never-irrigated (Zh-23) andirrigated (Zh-27-2) soils were compared. According to the international WRB classification, the non-irrigated soil Zh-23 is Calcaric Gypsisol (Abruptic, Katohypergypsic, Siltic), and the irrigated soil Zh-27-2 isassigned to Cambic Calcaric Gypsisols (Abruptic, Katohypergypsic, Siltic). The irrigated soil was irrigatedby aryk water for 80 years. The soils were studied by the soil-morphological method, by examination of undisturbed sample fragments under a low-magnification microscope, by soil thin section analysis, and by scanning electron microscopy. The efficiency of the express method of X-ray fluorescence analysis (XRF), usinga portable analyzer, and of the method of powder X-ray diffractometry (XRD) for assessing gypsum contentin gypsiferous horizons and parent material of Gypsisols was demonstrated. Macro- and micromorphologicalfeatures of the compared soils enabled the identification of three macromorphotypes and five micromorphotypes of gypsum-containing soil horizons. The predominant sizes of gypsum crystals and their shape in the horizon during terrain description were taken as the basis for identifying gypsum macromorphotypes. Characteristicmicrostructure expressed in combinations of gypsum crystals of certain sizes and shapes and their allocation tointer-aggregate voids (infillings) or intrapedal mass was taken into account to determine micromorphotypes.Micromorphological analysis helped to determine the genesis of the horizons and the processes developed inthe studied soils. Carbonate pseudomorphs of gypsum crystals are noticeable in both soils at the microlevel.However, the results of gypsum dissolution and recrystallization processes in the irrigated soil are most pronounced. At the sub-microlevel, the edge of lenticular gypsum in the irrigated soil is corroded, which indicatesthe dissolution of coarse gypsum aggregates under regular effect of irrigation water. The lower boundary ofoccurrence of crystals with the relief edge may indicate the depth of irrigation water penetration.