Many of Youngstown’s lakes and reservoirs are filling in with sed

Many of Youngstown’s lakes and reservoirs are filling in with sediments rapidly; however, the relative contributions from different land-cover types are not understood. Studies examining watershed contributions highlight agricultural and urban contributions ( Martin et al., 1998 and Das, 1999), but do not address specific Akt inhibitor contributions from urban forest covers, even though ∼13% of the area is covered by this particular land-cover type ( Korenic, 1999). We can now begin to evaluate this land cover’s regional contributions given this assessment of its erosive nature and basing

an appropriate C-factor value of ∼0.5 based on the USLE model calibration to a sediment record. This land cover has been overlooked as a significant sediment contributor; based on data from Lily Pond, it should be

one of the highest sediment producers in similar urban settings. High amounts of impervious surface would not generate sediment as soils are covered by asphalt and concrete; however, impervious urban covers increase surface runoff, which may have implications for higher erosion rates down-gradient ( Weng, 2001). This concept is also entertained as it may pertain to this study as hillslopes around Lily Pond may by eroding more heavily in response to increased runoff from Tenofovir cell line surrounding urban covers. Regardless, the contribution of forested urban lands to the sedimentation problems in reservoirs

cannot be overlooked considering that most of the urban forests in and around Youngstown are found along the steeper slopes connecting to higher-elevation urban areas with extensive impervious surface cover. In this respect, the study of Lily Pond provides urban managers with a baseline for assessing soil erosion across similar terrain types. Sedimentary studies at the smaller, sub-watershed scale are crucial to understanding local and regional USLE model applications. This study demonstrates how the USLE can be used to assess sediment contributions from small watersheds to ponds in urban environments to help constrain the effects of understudied land-cover types, such as urban forest. Published C-factors for a range of forest types across the globe vary by 3 orders of magnitude. Calibration of a USLE model pheromone from a sedimentologic investigation of Lily Pond suggests that urban land cover here should be assigned a C-factor on the high end of this spectrum. Although contributions from gully processes are not factored into the equation, a field-based assessment of gully contributions suggests they are minimal and do little to change confidence in the results. As urban expansion will continue to fragment landscapes and produce complex land-cover distributions an increased need should develop for investigating effects of different urban land-cover types on sediment yields.

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