The sediments in the reservoir record the multiple ways that urban activity can alter fluxes. Lower sedimentation rates and higher sediment-bound metals http://www.selleckchem.com/products/SP600125.html concentrated early in the record when industrial activity was more prevalent in the watershed; higher sedimentation rates and lower metals registered in more recent times when population in the watershed increased and industrial activities and power generation declined. The reservoir sediment record, coupled with modeling

of modern watershed sediment fluxes, is also useful for guiding management and predicting geomorphic changes that may occur when the old dams are removed and channel connectivity is restored. At a much smaller scale, Mattheus and Norton employ sediment records and erosion modeling to examine sediment generation in urban forests. Their results suggest that urban forests, which cover nearly 30% of US urban areas (Nowak et al., 2001), have unexpectedly high erosion rates relative to other forested landscapes. The authors suggest that these high erosion rates may result from upslope impervious surfaces generating erosive stormwater, or a legacy of check details forest harvest reducing the ecological complexity and erosion resistance of forested slopes. The contributions

by Mann and colleagues and Mattheus and Norton emphasize the importance of quantifying the heterogeneous impacts of human activities over time, even under relatively static land cover conditions. These studies also highlight important insights that can Tacrolimus (FK506) be gained by coupling sediment flux models with empirical data collection. Such multiple method

approaches are an important way forward for anthropogenic geomorphology studies to not only explain past and present impacts, but to make predictions of future forms and processes given increasing interactions between humans and the Earth surface. “
“Wilderness is defined in the U.S. 1964 Wilderness Act legislation “as an area where the earth and the community of life are untrammeled by man, where man himself is a visitor who does not remain.” This is a slightly more poetic rendering than the usual dictionary definitions of “a tract or region uncultivated by human beings” or “an area essentially undisturbed by human activity together with its naturally developed life community.” The common thread in diverse definitions of wilderness is the absence of humans and their influences. Opinions diverge on how strictly to interpret influences, or even on whether wilderness is anything but a social construct or a romantic myth (Lowenthal, 1964).