Proposal to Calculate Soil Loss in Claremont Canyon East Bay Hills Berkeley Wing Tai Kyle Tse Abstract Soil erosion and its effects negatively impact millions of lives and is responsible for widespread property damage in regions around the entire world It will become an increasingly critical problem if steps are not taken to regulate its effects On a smaller scale it is important to pinpoint estimated locations where soil erosion occurs in order to prevent substantial soil loss This project estimates the soil loss of Claremont Canyon part of the greater East Bay Hills There are three major landowners in Claremont Canyon they consist of the University of California Berkeley the East Bay Regional Park District and the City of Oakland In the past there have been fourteen major wildfires in the East Bay areas and assessment plans have been taken to reduce the fire risk These studies on the negative effects of soil loss from wildfire have not yet been extended to the Claremont Canyon regions This study will be conducted utilizing the Revised Universal Soil Loss Erosion Equation RUSLE to calculate the amount of annual soil loss The strength of this model permits an all inclusive analysis by breaking down soil erosion into elements based on vegetation soil types rainfall topography and urban land practice data Results predicted long term deterioration and provide a more accurate assessment for future developmental decision making on land use Introduction On average over 140 000 wildfires occur in the United States of America each year IBHS 2003 Such consistent and frequent occurrences of this natural disaster have negative impacts upon the environment Wildfires cause extensive soil erosion as the fire burns destroy the plant materials responsible for stabilizing the soil Fred Deneke 2002 In the past twentieth century fourteen major wildfires have swept through the East Bay Hills AEGIS 1995 Two out of the fourteen wildfires have also traversed through Claremont Canyon the 1923 Berkeley fire and the 1991 Oakland Hills fire In particular the latter has played a significant role in history as the fire ranks first amongst the most expensive fire disaster in California history The fire took 25 lives over 2700 structures and caused 1 68 billion dollars worth of damages AEGIS 1995 Such damages impacted the landowners of the regions Historically the Claremont Canyon is a wild interface land belonging to three major owners Figure 1 the University of California 150 acres Berkeley the East Bay Regional Park District 208 acres and the city of Oakland 13 acres The Claremont Canyon Conservancy 2003 Figure 1 Claremont Canyon Ownership Study Site Due to the experiences of seasonal fires the fire issue remains a concern to the three major owners as well as some small private owners in the Claremont Canyon Many studies aim to reduce the wildfire hazard by removing the coyote brush poison oak and eucalyptus trees in varies locations Wallace and McClung 2002 The majority of the studies are allocated to vegetation management whose approaches have been published in a manual by the East Bay Hills in order to inform the public planners to become more aware of the effects of wildfire on vegetation Danielsen et al 2002 However to my knowledge there exist no studies that have specifically focused on soil erosion in the Claremont Canyon Such a study would be beneficial to public planners in making future decisions A study focusing on the soil erosion occurring in Claremont Canyon will provide more details on wildfire feedback resulting in soil loss This information will be valuable to different owners who are trying to reduce the natural hazard occurrence on their properties within these areas Studies are needed to give a concrete informational basis to make rational decisions for landowners Therefore my objective is to identify the region of highest soil erosion in the Claremont Canyon East Bay Hills and Berkeley Methods In order to calculate the soil loss in Claremont Canyon the RUSLE is utilized in this project The RUSLE builds upon the Universal Soil Loss Equation USLE and this tool is designed and is currently implemented by soil conservationists Wischmeier and Smith 1978 The RUSLE is widely applied on studying urban land use and recreation sites Rennard et al 1991 In one previous study conducted on the United States Virgin Islands Radke 1995 used the RUSLE to estimate regions of high soil risk for soil loss on the hilly coastal areas My project structures itself along a similar model to calculate soil loss for Claremont Canyon A RUSLE model is composed of five variables and calculated from a formula that is written as A LS R C K P where A is the predicted average annual soil loss per unit area in ton ac 1 yr 1 LS are the slope length factor and slope steepness factor in dimensionless R is the rainfall runoff erosivity factor in hundreds of ft tons inch ac 1 hr 1 yr 1 C is the cover management factor in dimensionless K is the soil erodibility factor in tons hr hundreds of f tons 1 in 1 P is the support practice factor in dimensionless LS Factor The rate of soil erosion is greatly affected by the local topography of an area The LS factor provides a quantitative representation of both slope length and steepness ATTACC 1999 The slope steepness and length values for the LS factor were determined from a digital elevation model DEM an Arc Micro Language lsfactor aml and a C language program rusleinfo exe The LS factor is the first variable to be calculated in the RUSLE model To calculate the LS factor the following two step process was applied Step 1 A Triangulated Irregular Network TIN model was created for Claremont Canyon First the TIN model based on the hypsography data was obtained from the San Francisco Estuarine Institute SFEI Next the ArcGIS Three Dimensional Analyst tool was applied to the hypsography data The product result was a TIN model creating many sample points each having an x y and z coordinate Figure 2 These points are connected by edges to form a set of non overlapping triangles used to represent the topographical three dimensional surface Peschier 1996 Figure 2 The TIN model for Claremont Canyon Step 2 The U C Berkeley Applied Environmental Geographic Information System AEGIS laboratory provided an Arc Macro Language lsfactor aml and a C language program rusleinfo exe After running these programs on the TIN model each line segment of a triangle contains a LS factor representing areas where
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