title: Erosion rates as a potential bottom-up control of forest structural characteristics in the Sierra Nevada Mountains.
abstract: The physical characteristics of landscapes place fundamental constraints on vegetation growth and ecosystem function. In actively eroding landscapes, many of these characteristics are controlled by long-term erosion rates: increased erosion rates generate steeper topography and reduce the depth and extent of weathering, limiting moisture storage capacity and impacting nutrient availability. Despite the potentially important bottom-up control that erosion rates place on substrate characteristics, the relationship between the two is largely unexplored. We investigate spatial variations in aboveground biomass (AGB) across a structurally diverse mixed coniferous/deciduous forest with an order of magnitude erosion-rate gradient in the Northern Californian Sierra Nevada, USA, using high resolution LiDAR data and field plots. Mean basin slope, a proxy for erosion rate, accounts for 32% of variance in AGB within our field area (P < 0.001), considerably outweighing the effects of mean annual precipitation, temperature, and bedrock lithology. This highlights erosion rate as a potentially important, but hitherto unappreciated, control on AGB and forest structure.
authors.forename: David T
authors.initials: DT
authors.lastname: Milodowski
authors.forename: Simon M
authors.initials: SM
authors.lastname: Mudd
authors.forename: Edward T A
authors.initials: ET
authors.lastname: Mitchard
mesh_terms: D002140:California; D065928:Forests; D058998:Remote Sensing Technology; D012987:Soil
chemical_list: D012987:Soil