Understanding the spatial and temporal variation in soil temperatures is important to classification, land use, and management. To that end, mean annual soil temperature (MAST) data for Wisconsin and Michigan were modeled to (i) determine the effects of the Great Lakes and their snowbelts on soil temperatures, and (ii) better estimate the location of the boundary between the mesic and frigid soil temperature regimes in this region. The location of the mesic‐frigid (M‐F) line is particularly difficult to determine where east‐west gradients in air temperature cross north‐south trends in snowfall due to Lake Michigan. Additionally, the soil temperature regime of several Great Lakes' peninsulas near the M‐F line is in question. To determine the accuracy of our soil temperature model, soil temperature data output from it were compared with data derived from thermocouples implanted in soils at 39 sites in northern Michigan that had been collecting data several times daily for more than 6 yr. Error statistics for the model show that it has essentially no mean bias when examined on an annual basis or for winter, and only a bias of 0.1°C for the warm season. The M‐F line in Wisconsin and Michigan is slightly north of most previously estimated locations, and is strongly influenced by the snowbelt in southern Michigan. Soils in deep snow areas stay warmer in winter than do soils inland, increasing their MAST and forcing the M‐F line north of where air temperatures alone might have placed it. Lake‐effect areas also stay cold longer into the spring season, and cool down more slowly in fall. Soil temperatures in these areas are, therefore, more moderated on an annual basis, as indicated by coefficients of variation.

Metal-enriched sediments produced from Ag, Pb, and Zn mining bave been alluvially deposited on riparian areas along tbe Coeur d'Alene River in northern Idaho. Ten pedons were sampled with the objective to assess the influence of soil pedogenesis on the vertical distribution of Fe, Mn, and trace elements through tbese sediments and into the underlying native alluvial materials. Depth of metal-enricbed sediments varied from 20 to 104 cm. The pH was similar in both parent materials, ranging from 4.9 to 6.8. The metal-enriched sediments had a high concentration of Fe, Mn, and trace elements relative to horizons of native alluvium. Depth distribution of Fe, Mn, and ratios of Fe from selective dissolution as well as microscopic and macroscopic morphological expressions of redoximorphic features were evidence of pedogenic redistribution of elements. Results suggest that redistribution was largely driven by redox cbanges from seasonal flooding and bigb water tables, resulting in dissolution/precipitation of Fe-Mn hydrous oxides. Location of tbe highest concentration of elements varied with depth within the metalenriched zone and was not apparently linked to a hydrologie discontinuity between parent materials. Initial deposition of hydrous oxides may be in the capillary fringe above the water table, but data suggests that once a zone of secondary Fe deposition was established, this cementation likely influenced soil hydrology. Subsequent deposition of hydrous oxides apparently continued at this pedogenic interface. Iron was present in various forms (crystalline and noncrystalline hydrous oxides, metal-organic complexes with humic substances) and these compounds function as sinks for trace elements.Abbreviations: CEC, cation-exchange capacity; E|_|, redox potential; Ee^, dithionite citrateextractable Ee; EeyFe(, the ratio of dithionite citrate extractable iron to total iron; Fe,, total iron; ?e^, acid annmoniunn oxalate-extractable iron; ICP, inductively coupled plasma; Mn^j, dithionite citrate-extractable Mn; XRD, X-ray diffraction.