Special issue statement. This article is part of a special issue published on the occasion of the 70th anniversary of E&G Quaternary Science Journal (EGQSJ). The special issue celebrates the journal's notable contribution to Quaternary research by revisiting selected milestone articles published in the long history of EGQSJ. The German Quaternary Association (DEUQUA) presents translations of the originals and critical appraisals of their impact in tandem anniversary issues of DEUQUASP and EGQSJ, respectively.

Original article: https://doi.org/10.3285/eg.22.1.12

Translation: https://doi.org/10.5194/deuquasp-3-111-2021

Smolíková was one of the first pedologists who pointed out that paleosol horizons in Quaternary paleosol–sediment successions are often described by Quaternary geologists who are not trained in pedology and that it may increase the problems with the interpretations. As a result, many existing descriptions of paleosols in the literature were hardly pedologically interpreted in terms of the kind of pedogenic processes and the environmental conditions that they are indicative of. She pointed out that the description and interpretation of paleosols must be linked to a profound taxonomy of soils, including all kinds of soil formation in all possible stages of development. Smolíková (1971) further highlighted the importance of the position of the soil profile in the landscape and that the influence of relief has to be considered. If possible, soil horizons should be observed along some distance in order to recognize reworking, disturbance and accumulation of soil sediments.

Her seminal paper discussed here is an outstanding example of how the views of geologists, environmentalists and archeologists on pedocomplexes can be united. The concept of Quaternary climatic division was followed by Smolíková in her micromorphological description of pedocomplexes (Němeček et al., 1990), and its link to the soil genesis and environmental conditions under which pedocomplexes developed represent the main message of her work. The problems of this “early” paleopedological work was the non-stable soil terminology. Smolíková often described the micromorphological properties and linked them to the types of soils which are, however, recently not used any more. Later, when the pedological system changed, Smolíková did not adapt her terminology to it. Therefore, it is complicated to use the terminology and interpretation from the time when she investigated the old localities (Adameková et al., 2021). Another problem with the application of her terminology applied to the pedocomplexes is due to the increasing knowledge of climatic changes. Since the publication of Smolíková's work, i.e., over the last 50 years, the understanding of the situation of the climatic development of the last glacial cycle in Central Europe, as well as the understanding of the situation of the Paleolithic, has changed significantly. The system of pedocomplexes, which document the so-called warm phases (interglacials or interstadials), is only suitable for a more general division of the entire Pleistocene. On a detailed scale, however, they are often unsatisfactory.

An example of the unsatisfactory basic division is the last glacial, in which Smolíková separated two pedocomplexes called PKI and PKII. However, later research revealed that there had developed another paleosol between these two pedocomplexes, the preservation of which is simultaneously affected by erosion processes. This pedocomplex is the so-called Bohunice soil after its eponymous locality, Bohunice in Brno. From the point of view of Paleolithic research, this pedocomplex is crucial because industry from the turn of the Middle and Upper Paleolithic (early Upper Paleolithic: Bohunician, Szeletian, Aurignacian) is tied to it. Later, Smolíková, as a co-author in the first comprehensive monograph on pedology and paleopedology published in Czechoslovakia (Němeček et al., 1990), significantly expanded the paleopedological and paleogeographic concepts published in her article commented upon herein concerning the use of pedological data in the Quaternary. There, she described in detail the importance of paleopedology for the understanding of paleoclimate and paleogeography during the Quaternary in Central Europe. It clearly defined the patterns of soil development in the Quaternary cycle and emphasized the importance of soils as part of Quaternary geology. Probably the most important contributions to the study of Quaternary paleosols are specific micromorphological descriptions of these soils and a description of the genesis of these soils on individual soil-forming substrates preserved in a whole range of Quaternary sediments, especially in loess.

To connect pedology with Quaternary research, Smolíková used a basic methodological tool, namely the microstructure of soils, i.e., the so-called soil micromorphology. In addition to the microstructure itself, the type and degree of preservation of organic and organomineral soil components can be described, as well as the pedofeatures related to soil development; further, post-sedimentary processes can be detected. This can be quite complex and might reflect the changing climatic conditions of the site.

The study of soil microstructure was introduced into the literature in the 1930s by Kubiëna (exact year unknown). Smolíková was a student of Kubiëna and took over his terminology, which she began to apply to the study of paleosols in the Central European context in the 1960s. In the 1960s, Brewer (1964) proposed a more systematic, morphological approach to the description of soil samples, followed by a number of other authors. The efforts of the 3rd International Meeting on Soil Micromorphology in Wroclaw (Poland) in 1969 resulted in a long-term accepted terminology and a standard way to describe thin sections (Bullock et al., 1985). This terminology is widely used up today, but most of the researchers combine that terminology with the more systematic terminology of Stoops (2003).

At the time when Smolíková published her annotated article, interest in the importance of paleosols was not only in the context of archeology (Lisá et al, 2015), but it intensified especially in the 1970s when Kukla suggested to the president of the United States the importance of studying paleosols in the context of future climate change (i.e., global cooling versus global warming). On this account, Kukla created the above-mentioned concept of pedocomplexes, which Smolíková elaborated in terms of soil micromorphology (Němeček et al., 1990). The principles on the basis of which pedocomplexes were determined are described in great detail in her 1971 article. Smolíková's (1971) article, and the way in which it used soil micromorphology, was therefore completely original for its time. In our opinion, it has become a building stone for further studies of a similar type. Since then, a number of studies have been published in which soil micromorphology has played a crucial role in recognizing soil processes that reflect the relatively complex conditions of a changing climate.

Further, Smolíková (1971) showed one very important aspect when interpreting the differences in soil development. In her work, she strongly refers to zonal concepts that have also become outdated. Recent and subrecent soil cover that developed on loess substrate over the Holocene in Central and Western Europe differs according to the continental gradient and as a result of orographic influences (e.g., rain shadow effect). Such effects controlled the spatial differences in pedogenesis in loess also under past climatic conditions. Smolíková (1971) also pointed out the importance of comparing pedological characteristics of paleosols with their modern analogs, which allows for the reconstruction of the climatic conditions that prevailed during their formation. In this respect, she highlights the use of micromorphology, together with pollen, kernels of fruits, phytoliths, rhizoliths, and mollusk shells, for a detailed characterization of the pedogenic features that can be identified in a paleosol. Her recommendations were crucial for understanding the importance of the identification of the environmental conditions when interpreting buried paleosols.

The article processing charge was funded by the Quaternary scientific community, as represented by the host institution of EGQSJ, the German Quaternary Association (DEUQUA).

This paper was edited by Christine Thiel and reviewed by one anonymous referee.