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Meander erosional banks of fifth and sixth order southwestern Wisconsin streams having drainage areas of twenty square miles (30 km2) or less frequently reveal three distinct sedimentary sequences. The basal unit of coarse textured debris is thought to represent bed load sediment of a prior channel active near the terminus of a mid-Holocene drought about 6,000 years B. P. A silty clay series over the coarse layer is interpreted to have been derived by vertical accretion on a paleo floodplain during a climatic shift toward more humid conditions of the late Holocene. Distinctly laminated silt loam sediments produced by vertical accretion extend from the middle series to the current surface, and mainly result from increased flooding related to modern land use practices. The recent man-induced change in channel morphology is analogous to natural adjustments produced by Holocene climatic fluctuation, and suggests that temporal aspects of channel and floodplain evolution may be described by a step function model. KEY WORDS: Biogeomorphic response, Climatic change, Floodplain, Holocene, Valley alluviation, Wisconsin.HE morphology of stream channels and T floodplains is controlled by the physical environment of the contributing drainage basin. Maintenance or change of an established system of alluvial morphology is highly regulated by the rates of surface runoff and sediment yield. The purpose of this study is to analyze the fluvial adjustments that have occurred in response to known or presumed changes in surface runoff and sediment yield.The study area is restricted to southwestern Wisconsin valleys of fifth and sixth order having drainage areas of twenty square miles (30 km2) or less. Meander erosional banks of the fifth and sixth order streams frequently reveal three distinct sedimentary sequences : basal coarse gravel overlain by silty clay in turn overlain by recent alluvium. I will attempt to demonstrate that the lower and intermediate series are products of channel and floodplain response to

Structured adsorbents, especially in the form of monolithic contactors, offer an excellent gas-solid contacting strategy for the development of practical and scalable CO capture technologies. In this study, the fabrication of three-dimensional (3D)-printed 13X and 5A zeolite monoliths with novel structures and their use in CO removal from air are reported. The physical and structural properties of these printed monoliths are evaluated and compared with their powder counterparts. Our results indicate that 3D-printed monoliths with zeolite loadings as high as 90 wt % exhibit adsorption uptake that is comparable to that of powder sorbents. The adsorption capacities of 5A and 13X monoliths were found to be 1.59 and 1.60 mmol/g, respectively, using 5000 ppm (0.5%) CO in nitrogen at room temperature. The dynamic CO/N breakthrough experiments show relatively fast dynamics for monolithic structures. In addition, the printed zeolite monoliths show reasonably good mechanical stability that can eventually prevent attrition and dusting issues commonly encountered in traditional pellets and beads packing systems. The 3D printing technique offers an alternative, cost-effective, and facile approach to fabricate structured adsorbents with tunable structural, chemical, and mechanical properties for use in gas separation processes.

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The conversion of natural land cover to agricultural land uses in the Platte watershed of southwestern Wisconsin caused a three-to fivefold increase in the magnitudes of floods that recur more frequently than once in five years in the small headwater and tributary watersheds. The impact of settlement on floods is less for larger watersheds, but the general impact of settlement has caused a major channel metamorphosis throughout the Platte River channel system. Most headwater and tributary channels have modern channel cross sections that are relatively wide and shallow when compared to their presettlement counterparts. Most channel cross sections along the downstream main channel, beyond the channel reaches where bedload sediments are a dominant factor in determining channel shape, are narrow and deep relative to their presettlement counterparts. Much of the sediment that is related to man-induced accelerated surface runoff has been transported only short distances and is presently deposited on alluvial fans and floodplain surfaces. Historical floodplain alluviation varies in thickness from about one and one-half feet (0.5 m ) in the headwaters to about twelve feet (4 m) near the mouth of the river. The morphology of channels and the mobility and storage of sediments in the Platte watershed responded quickly to environmental changes in the watershed. TREAM channels develop morphological

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