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We review historical soil maps from a geographical perspective, in contrast to the more traditional temporal–historical perspective. Our geographical approach examines and compares soil maps based on their scale and classification system. To analyze the connection between scale in historical soil maps and their associated classification systems, we place soil maps into three categories of cartographic scale. We then examine how categories of cartographic scale correspond to the selection of environmental soil predictors used to initially create the maps, as reflected by the maps' legend. Previous analyses of soil mapping from the temporal perspective have concluded that soil classification systems have co-evolved with gains in soil knowledge. We conclude that paradigm shifts in soil mapping and classification can be better explained by not only their correlation to historical improvements in scientific understanding, but also by differences in purpose for mapping, and due to advancements in geographic technology. We observe that, throughout history, small cartographic scale maps have tended to emphasize climate–vegetation zonation. Medium cartographic scale maps have put more emphasis on parent material as a variable to explain soil distributions. And finally, soil maps at large cartographic scales have relied more on topography as a predictive factor. Importantly, a key characteristic of modern soil classification systems is their multi-scale approach, which incorporates these phenomena scales within their classification hierarchies. Although most modern soil classification systems are based on soil properties, the soil map remains a model, the purpose of which is to predict the spatial distributions of those properties. Hence, multi-scale classification systems still tend to be organized, at least in part, by this observed spatial hierarchy. Although the hierarchy observed in this study is generally known in pedology today, it also represents a new view on the evolution of soil science. Increased recognition of this hierarchy may also help to more holistically combine soil formation factors with soil geography and pattern, particularly in the context of digital soil mapping. [ABSTRACT FROM AUTHOR]

Abstract: Soil mapping is a major goal of soil science. Soil maps rely upon accurate base maps, both for positional reference and to provide environmental data that can assist in the prediction of soil properties. This paper reviews the historical development of base maps used for soil mapping, and evaluates the dependence of soil mapping on base maps. The availability of geographic technology for producing base maps has both constrained and directed the geographic study of soil. The lack of accurate methods for determining location limited early geographic descriptions of soils to narratives, or to listings of attributes for property-based map units. The first real base maps available for soil mapping were outline maps produced in the late 18th century, fueled by governments' interests in documenting national boundaries and popular interest in world atlases. These early soil maps primarily used outline maps as a positional reference onto which soil-related thematic detail was added. Eventually, additional spatial information, in the form of topographic maps and later aerial photographs, increased the predictive role of base maps in soil mapping. In the current digital, geospatial revolution, global positioning systems and geographic information systems have nearly replaced the positional reference function of base maps. Today, base maps are more likely to be used as parameters in soil-landscape models for predicting the spatial distribution of soil properties and classes. Formerly, as a reference for spatial position, paper base maps controlled the cartographic scale of soil maps. However, this relationship is no longer true in geographic information systems. Today, as parameters for digital soil maps, base maps constitute the library of predictive variables and constrain the supported resolution of the soil map. [Copyright &y& Elsevier]

Sediments and stratigraphy at the Tower Buried Forest site provide a glimpse into the immediate post-glacial environment of northern Lower Michigan, USA. At this site, sandy glacial outwash is overlain by (1) ≈37 cm of peat associated with a wetland, above which are (2) flat-lying spruce and larch logs and branches that date between ≈10 910 and 10 340 cal years BP. Above the woody materials are ≈55-75 cm of sand, interbedded with organic muck laminae, which we interpret as local alluvium. This stratigraphic sequence is overlain by muck soil materials associated with the modern wetland. Pollen and plant macrofossil analysis of the lower peat indicate that a tundra-boreal parkland had been established here, shortly after final deglaciation. Later, Picea glauca (white spruce) , Picea mariana (black spruce), Larix laricina (larch), and Abies balsamea (balsam fir) became abundant in an open boreal forest - Spaghnum peatland. Subsequent increases in Pinus (pine) and Typha (cattail) indicate drying and possibly warming conditions. At ca. 10 340 cal years BP (or a few centuries prior), nearly two millennia after final deglaciation, water flowed across the site, possibly knocking over the trees.. Interbedded sand and muck deposits above the flat-lying logs are interpreted as alluvial deposits from this event, after which the wetland became quiescent again. [ABSTRACT FROM AUTHOR]

We modeled soil temperatures at 50-cm depth, using 1951–2000 air temperature and precipitation data from 194 National Weather Service stations in Wisconsin and Michigan. The accuracy and bias of the physical model used in this study were validated by comparing its output data to 22,401 actual soil temperature readings taken from sandy soils at thirty-nine forested sites throughout northern Michigan; the model was shown to have almost no temperature bias. Although mean annual air temperatures across the region show no strong spatial or temporal trends over the fifty-year period, at many sites, especially in Wisconsin, wintertime air temperatures have been increasing slightly in recent years. Conversely, mean annual soil temperatures have been decreasing at most sites in the region, some by more than 0.5°C. Likewise, wintertime soil temperatures are also decreasing, especially at sites downwind from the Great Lakes—many of which are in snowbelt locations. Increasing wintertime air temperatures over the past fifty years coincide with (and probably have led to) more variable and thinner snowpacks, lessening their insulating impact and contributing to decreasing wintertime soil temperatures that our model show are occurring in the eastern and northern parts of the region. These findings illustrate the complex response of natural systems to slow atmospheric warming, and draw attention to the potential changes that are occurring in growing season characteristics, phenology, and spring runoff characteristics in the Great Lakes region. [ABSTRACT FROM AUTHOR]

Glacial Lake Algonquin, the most widespread proglacial lake in the Great Lakes basin, attained a high (Main) stage at about 11,000 b.p., at which time it developed a conspicuous shoreline. Several lower, less obvious Algonquin shorelines also exist. Previous research on this lake has involved three drawbacks: (1) imprecise methods of establishing the location and elevation of shoreline features, (2) misidentification of some offshore coastal landforms as beach ridges, and (3) tenuous and difficult correlation of named shorelines across wide distances. We believe that more than one name is used for some lake phases, making correlation difficult. Our study focused on these problems by surveying and mapping 160 Algonquin wave–cut bluffs throughout northern Michigan. We utilized global positioning system (GPS) technology to precisely record the three–dimensional positions of the bases of these bluffs and statistically fit trend surfaces to these positions. Classification of bluff data indicates that four strong Algonquin shorelines exist in the region, for which we recommend these names: Main, Ardtrea, Wyebridge, and Payette. Weak evidence for a possible fifth, lower shoreline was observed at five locations. Maps of the landscape during each lake phase were created, revealing islands not previously recognized. Rebound curves and maps of the lake during each phase, using the positional data set, indicate that isostatic rebound in the study area appears to be greatest in the northeast sector. [ABSTRACT FROM AUTHOR]

Describes and explains the geographic distribution of Spodosol soils (Podzols) on a regional scale. Because they employed a spatially-based, functional-factorial model of soil formation and, held four factors constant, they were able to examine the effects of climate on soil genesis and distribution. Patterns in southern Michigan; Methods; Results and discussion; Conclusions.

Post-disturbance pedogenetic pathways were characterized in three landscapes representing different degrees of weathering and leaching. Tree uprooting has been the main form of disturbance in all three landscapes. We hypothesized that the pedogenetic effect of trees due to uprooting is mainly governed by the regional degree of pedogenesis, which in turn affects soil and landscape evolution. The three regions were characterized by a chronosequence of treethrow pit-mound pairs, from fresh to almost leveled forms. Two sequences originated from the Czech Republic, one on Haplic Cambisols and one on Entic Podzols. The third and the oldest chronosequence, in Michigan, USA, was on Albic Podzols (dating back to 4080 BCE). We analyzed 38 chemical and physical soil properties for 700 samples from 42 pit-mound pairs in these regions. Ordination and regression techniques allowed us to evaluate the effect of sample depth, microsite (pit, mound, and undisturbed control position), and age of the soils formed after uprooting. Depth was the most significant variable in all regions ( p < 0.001), followed by microsite location, and then age (time since disturbance). The significance of these variables decreased with increasing weathering and leaching intensity. The results suggest that intense pedogenesis, as at the Michigan site, decreases the polygenetic impacts of uprooting on soil development pathways. On Haplic Cambisols, disturbances increased the local variability of pedogenic processes by changing melanization and hydromorphic processes, as well as by mineral alteration. Conversely, on Albic Podzols, we found comparative chemical uniformity in post-uprooting pedogenesis between microsites, despite rapid podzolization in pits and slower podzolization on mounds. The general chemical convergence of pedogenesis in these landscapes towards vertically-dominated podzolization may limit divergence of pedogenic pathways after a disturbance. The formation and translocation of labile organic matter-sesquioxide complexes in the uppermost podzolic horizons in Entic Podzolś was a key threshold, in that it changed the pedochemical, ecological and biogeomorphic role of the treethrow features in the soil and landscape evolution. Although treethrow pits were accumulation sites for soil elements in Haplic Cambisols and Entic Podzols, they were microsites of intense leaching and elemental loss in Albic Podzols. [ABSTRACT FROM AUTHOR]