Sola Incognita: Unsolved Pedogenetic Challenges

Abstract

For the anniversary of the Faculty of Soil Science of Moscow State University, the author examines the issues that have remained unresolved in the field of classical genetic soil science over the past half century, and offers a list of tasks that need to be solved in the near future. It is noted that against the background of decreased interest in pedogenetic research, problems are accumulating in related fields that require a clear understanding of the genesis of soils: soil classification, digital soil mapping, paleopedology and soil assessment. One of the unsolved issues remains the estimation of the rates of soilforming processes, without which it is dificult both to reconstruct the evolution of soils in the past and to predict the behavior of soil systems in the future. The mechanisms of textural differentiation have not been deciphered both in temperate regions and in the tropics; in many cases, soils clearly differentiated by the content of the clay fraction are adjacent to soils with a profile homogeneous in texture. The mechanisms of deep illuviation of humus are unknown in the absence of signs of spodic or natric properties. There is no clear understanding of the mechanisms of formation of compacted subsurface horizons of soils (fragipan) and horizons cemented with opal (duripan). It is proposed to create a bank of unresolved soilgenetic issues that require analysis and solution