Quaternary Soil Profile and Paleoenvironmental Reconstructions In Archaeology


One of the earliest uses of soils in archaeological research, in addition to stratigraphic markers, was as paleoenvironmental indicators. Similar to soil stratigraphy, the use of soils as environmental indicators in archaeological research probably has its roots in Quaternary geology . Quaternary geologists and geomorphologists working with archaeologists were quick to use soils as clues to past environments . Likewise, the nature of prehistoric environments has long been a fundamental question in archaeology. Recognition of the relationship of soil development and morphology to environmental conditions goes back to the beginning of modern pedology, in the later 19th century in Russia and in the early 20th century in the United States . Climate and
vegetation in particular were understood as important soil-forming factors long before Jenny produced his landmark volume on Factors of Soil Formation (1941). What Jenny (1941, 1980) brought to the discussion was a theoretical means,  using the state factor approach, of assessing the effect of vegetation and climate on soils. By understanding these relationships via biosequences or climosequences, we are theoretically able to pick out the morphological and chemical characteristics of soils that are linked to climate or to vegetation. Climate most directly
influences pedogenesis through precipitation and temperature and influences pedogenesis indirectly through vegetation. The most direct effects of biota prob-188 ably come from the addition of a wide range of chemical compounds, from bioturbation, and from rooting.
This chapter is a discussion of those characteristics of soils that have some utility for environmental reconstructions, including climate and vegetation estimates. The chapter also includes some discussion of the potential pitfalls inusing soils as paleoenvironmental indicators. Longer and more in-depth discussions of soil–environment relationships in the context of soil geomorphology or environmental reconstruction are presented by Birkeland. 

The discussion is divided into five sections. The first is a discussion of some issues that greatly complicate if not completely stymie the use of soils as environmental indicators. These fundamental issues are critical to the subsequent discussions. The next three sections deal with the use of soil morphology (bothspecific pedogenic features and overall profile morphology) and of soil classification (following soil taxonomy) for environmental reconstructions and include
many cautionary notes. Soils have been misunderstood and misused in environmental reconstructions, so both the uses as well as the misuses are presented. Understanding the potential problems in the misapplication of soils is as important as understanding the positive applications. . A considerable amount of this work focuses on stable isotopes that accumulated in soil horizons.The preservation of these isotopic signatures of past vegetation and climate is intimately related to pedogenic properties and processes, so this method is appropriate to a discussion of soils as environmental indicators. However, there is no discussion of the use of plant fossils such as pollen or phytoliths recovered from soils. That is the realm of paleobotany, and the reader is directed to the large archaeologically oriented literature in that field. 
Some data indicate that the magnetic signal of buried soils is directly linked to the duration
and climatic conditions of pedogenesis (Verosub et al., 1993). Others argue, however, that the origin of the magnetic properties, whether related to primary loess deposition or to pedogenesis or to some combination, is unclear (Meng et al., 1997; Kemp et al., 1996; Kemp and Derbyshire, 1998). This technique, therefore, is not included in the chapter. Several definitions must be presented before proceeding with the discussion of soils as environmental indicators in archaeological contexts. The terms “environment” and “climate” (and especially  “paleoenvironment” and “paleoclimate”) often seem to be used interchangeably, but one is relatively specific and the other more general. Environment “encompasses all the physical and biological elements and relationships that impinge upon a living being. Specification of an organism’s environment emphasizes those variable relevant to the life of that organism—ideally, almost every aspect of its surroundings” . Climate, in contrast, refers to the regional, long-term characteristics of weather patterns such as average precipitation, average temperatures, and seasonal fluctuations; “the atmospheric conditions typical of the location” . In looking at proxy indicators of climate the intent is usually to get at relatively specific kinds of information about temperature or precipitation. The reconstruction of environments, however, can be much more
general but also very localized, such as the reconstruction of poorly drained, boglike conditions. Soils are better suited for environmental reconstructions, though as discussed below, under some circumstances a degree of climatic or even vegetation specificity can be involved. 
Notes and References.
1. Butzer, K. W., 1973. Spring sediments from the Acheulian site at Amanzi (Uitenhage
District, South Africa). Quaternaria 17, 299–319.
2. Soils in Archaeological Research. Vance T. Holliday; Oxford University Press, Inc.
198 Madison Avenue, New York, New York 10016.
3. Butzer, K.W., 1981. Rise and fall of Axum, Ethiopia: A geo-archaeological interpretation.
American Antiquity 46, 471–495.
4. Butzer, K. W., 1982. Archaeology as Human Ecology. Cambridge University Press,
Cambridge. 
5. Dincauze, D. F., 2000. Environmental Archaeology: Principles and Practice. Cambridge
University Press, New York.

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