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Students in a graduate seminar at Michigan State University produced a series of detailed vegetation, soils, and landform maps of a 1.5-square-mile (3.9 [km.sup.2]) study area in southwest Lower Michigan. The learning outcomes (maps) and skill development objectives (sampling strategies and various GIS applications) of this field-intensive mapping experience were driven by the assumption that students learn and understand relationships among physical landscape variables better by mapping them than they would in a classroom-based experience. The group-based, problem-solving format was also intended to foster collaboration and camaraderie. The study area lies within a complex, interlobate moraine. Fieldwork involved mapping in groups of two or three, as well as soil and vegetation sampling. Spatial data products assembled and used in the project included topographic maps, a digital elevation model (DEM), aerial photographs, and NRCS (National Resource Conservation Service) soil maps. Most of the soils are dry and sandy, with the main differentiating characteristic being the amount of, and depth to, subsurface clay bands (lamellae) or gravelly zones. The presettlement (early 1830s) vegetation of the area was oak forest, oak savanna, and black oak 'barrens.' Upland sites currently support closed forests of white, black, and red oak, with a red maple, dogwood, and sassafras understory. Ecological data suggest that these oak forests will, barring major disturbance, become increasingly dominated by red maple. This group-based, problem-solving approach to physical geography education has several advantages over traditional classroom-based teaching and could also be successfully applied in other, field-related disciplines. Key Words: pedagogy, fieldwork, mapping, problem-based learning, vegetation.

In this study, we used spatial data on soils, near-surface stratigraphy, and paleotopography to reinterpret part of the Late Pleistocene history of northeastern (NE) lower Michigan. We determined the relationships between various soil series and their likely sedimentary environments. Maps of these soil series for two counties in NE lower Michigan were then prepared within a geographic information system (GIS) to interpret the spatial patterns of the sedimentary environments on the paleolandscape which had been 'downwarped' within a GIS to account for isostatic rebound. Our primary finding centers on the origin and distribution of clayey, lacustrine sediments in the region. These clays are found in swales between drumlins and on ground moraines. They occur, however, at elevations up to 60 m above any previously known paleolake. Although it is widely known that low-lying, clay-dominated areas near the Lake Huron and Lake Michigan basins were inundated by paleolakes in the Late Pleistocene, thick deposits of lacustrine sediments between drumlins in the high interior of this region suggest that it, too, was periodically submerged between 11,200 and 13,000 yrs B.P. Additionally, the crests of these drumlins are covered with 50-100 cm of sediment that appears to have been water-worked at some time in the past, overlying a denser, less altered till. We argue that a previously unknown lake, or series of interconnected lakes, existed across the uplands of this landscape. Stratified silts and clays were deposited beneath this water body, which was ponded between the Port Huron moraine to the south and an advancing, stagnant, or retreating ice margin to the north and east, and may have discharged to the south across a low section of the moraine. Our findings underscore the complex interactions among ice sheets, meltwater, and preexisting landscapes during final deglaciation, and should assist those who seek to understand and explain modem soil and biotic patterns on those landscapes. We hope that our preliminary findings facilitate further hypothesis generation and testing regarding this lake(s), this landscape, and their coevolution. Key Words: glacial geomorphology, soil geography, paleolakes, lacustrine clays, paleoenvironmental reconstruction, GIS, Digital Evaluation Models.

This study describes and explains the geographic distribution of Spodosol soils (Podzols) on a regional scale. We employ a spatially-based, functional-factorial model of soil formation and, by holding four factors constant, are able to examine the effects of climate on soil genesis and distribution. Analysis of soils data for the southern peninsula of Michigan reveals that well and moderately well-drained, sandy Spodosols are found primarily in the northern half of the region in association with mixed coniferous-deciduous forest. Within this 'Spodosol province,' degree of soil development varies markedly. Differences in degree of soil development among sandy sites appear to be independent of present-day (or presettlement), regional vegetation patterns and may be related to variations in climate. Infiltration and 'soil freezing potential,' calculated using a hydrologic model, as well as air temperature records, are analyzed to ascertain which climate factors best correspond to observed trends in Spodosol development. Soils with strong spodic development exist in areas of northwestern southern (lower) Michigan that commonly experience deep lake-effect snows. Deep snowpacks in early winter inhibit soil frost, allowing for unrestricted infiltration of meltwater into the mineral soil during the spring snowmelt period (March and April). Correspondence between areas of increased autumn infiltration and strong Spodosol development suggests that wet soil conditions at the onset of winter also have impact on soil development, probably by inhibiting soil frost. Whereas the overall distribution of Spodosols is related to a coniferous component in the forest, variation in the degree of Spodosol development appears to be related to the frequency of years with high amounts of snowmelt infiltration, which intensifies the podzolization process. Key Words: infiltration, snowmelt, forest hydrology, podzolization, pedogenesis, soil geography.

Gravel distribution within treethrow mounds and adjacent undisturbed soils in Wisconsin and Pennsylvania were examined to determine the pedoturbation effects of tree uprooting. Erosion of fine materials from the fresh root plate and subsequent treethrow mound leaves gravels as a lag deposit forming surface gravel armors. Continued slow erosion of remaining nongravelly materials diminishes topographic expression of the mound. In time, gravel armors remain as the only evidence of past uprooting events. Key Words: treethrow, microtopography, gravel armor, pedoturbation.

The geography of soil is more important today than ever before. Models of environmental systems and myriad direct field applications depend on accurate information about soil properties and their spatial distribution. Many of these applications play a critical role in managing and preparing for issues of food security, water supply, and climate change. The capability to deliver soil maps with the accuracy and resolution needed by land use planning, precision agriculture, as well as hydrologic and meteorologic models is, fortunately, on the horizon due to advances in the geospatial revolution. Digital soil mapping, which utilizes spatial statistics and data provided by modern geospatial technologies, has now become an established area of study for soil scientists. Over 100 articles on digital soil mapping were published in 2018. The first and second generations of soil mapping thrived from collaborations between Earth scientists and geographers. As we enter the dawn of the third generation of soil maps, those collaborations remain essential. To that end, we review the historical connections between soil science and geography, examine the recent disconnect between those disciplines, and draw attention to opportunities for the reinvigoration of the long-standing field of soil geography. Finally, we emphasize the importance of this reinvigoration to geographers. [ABSTRACT FROM AUTHOR]

To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1467-8306.2006.00517.x Byline: Randall J. Schaetzl (*), Sharon Anderson (*) Keywords: pedology; soil genesis; soil geomorphology Author Affiliation: (*)Department of Geography, University of Wisconsin-Madison