Mapping Changes in Desert Pavement Surfaces of the Lower Colorado Desert of Southern California using Landsat Time Series Analysis

Christopher Potter

doi:10.23953/cloud.ijarsg.57

Abstract

Potential disturbance of desert soils from renewable energy development in southern California is receiving increasing attention due to potential impacts on air quality and greenhouse gas emissions. This study was designed to quantify and map, for the first time, changes in desert pavement surface area using 20 years of Landsat satellite image data across the Lower Colorado Desert. Landsat-derived maps of geomorphic surface classes from 1990 to 2014 for the Lower Colorado Desert area showed that a relatively stable area of around 1920 km 2 was covered by well-developed desert pavements prior to 2014. Based on 2014 Landsat imagery, coverage of well-developed pavements within solar energy development boundaries of the Lower Colorado Desert area totaled to 421 km 2 , the majority of which (>82%) were located in eastern Riverside County. If disturbed as a result of construction activities, these desert pavements could become a source of dust from exposure of the underlying fine particle layer.

Highlights

A desert pavement is an arid land surface that is covered with closely packed, interlocking angular or rounded rock fragments of pebble and cobble size (Cooke and Warren, 1973)
Near cloud-free imagery from the Landsat sensor was selected from the United States Geological Survey (USGS) Earth Explorer data portal
For the Landsat 4-5 Thematic Mapper (TM) images acquired between 1985 and 2011, 30-m resolution surface reflectance data were generated from the Landsat Ecosystem Disturbance Adaptive Processing System (Masek et al, 2006)

Summary

Introduction

A desert pavement is an arid land surface that is covered with closely packed, interlocking angular or rounded rock fragments of pebble and cobble size (Cooke and Warren, 1973). The Av layer consists of dust-sized wind-deposited particles underneath the pavement. One theory for the formation of desert pavements is based on the shrink/swell properties of the clay underneath the surface stones and gravel. Trapped by slowing wind speed due to surface roughness, dust particles land on the surface and subsequently work their way down between surface gravels. The physical shrinking and swelling processes of clay stemming from drying and wetting result in lifting a gravel layer to the surface and form a desert pavement.

Methods

Results

Conclusion