SUBSTANTIVE-GENETIC PRINCIPLES OF SOIL CLASSIFICATION AND DIAGNOSTICS IN THE SCIENTIFIC HERITAGE OF NABOKIKH O.G.

Abstract

Problem Statement and Purpose. Alexander Nabokikh (1874–1920), who criticized the model of soil classification and diagnostics by V. Dokuchaev and M. Sibirtsev, formulated the original water-mode concept of soil formation. This concept provided for the quantitative assessment of individual soil formation factors, as well as the classification and diagnosis of soils according to their characteristics and properties. Nabokikh ideas and methods were rejected by V. Dokuchaev’s students and have not been improved throughout the history of genetic soil science, but today they are clearly reflected in the «newest» substantive principles of soil diagnosis and classification. The methodological innovations of O. Nabokikh are far-sighted and relevant to this day and require a thorough study. Data & Methods. General scientific and historical methods were used. The research materials are the scientific works of O. Nabokikh, as well as archival materials of the Soil Museum of Odesa State Agrarian University. The maps of «selected major soil properties» of 1914–1916 were analyzed – detailed plans of organic matter content in the soils of the southern region of Ukraine. Results. O. G. Nabokikh proposed the Three-phase soil survey, which was based on methods of soil diagnostics by their properties, as well as the method of mapping the so-called “selected major soil properties”. Nabokikh foresaw the importance of detailed maps of the distribution of soil properties for soil monitoring. A comparative analysis of the data on organic matter content in the early twentieth century and in the early twenty-first century along two (n=94) of O. Nabokikh’s routes in the Odesa region revealed a decrease in organic matter in the surface layer of soils by an average of 0.6%. Nabokikh O. G. remained a supporter of the factor concept of soil formation, but modified it by identifying the “dominant factor” (an inseparable pair of precipitation and relief). In the matter of soil diagnostics and classification, he prefers the substantive principle. When identifying “variants of chernozems,” he cites the following substantive “main features of chernozems and the main modifications of these features”: uniformity of distribution of silicate minerals; accumulation of humus; illuvium of hydrates of one and a half oxides; illuvium of calcium carbonate salts; relict features. Determination of the main features of soils became the basis of the deep-profile method of soil research used by Nabokikh O. G.