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Date Permissions Signed


Date of Award

Fall 2019

Document Type

Masters Thesis

Department or Program Affiliation

Environmental Science

Degree Name

Master of Science (MS)


Environmental Sciences

First Advisor

All, John

Second Advisor

Matthews, Robin A., 1952-

Third Advisor

Bach, Andrew J.

Fourth Advisor

Pricope, Narcisa


This study developed a Rangeland Degradation Risk Model for the Peruvian Andes based on the Unit Stream Powered Erosion Deposition Model using globally available datasets. A supervised land cover classification was conducted to identify suitable grazing areas and to conduct a regional analysis of susceptibility to erosion. Field data were collected from two different study sites, Huascaran National Park and Nor Yauyos Cochas Landscape Reserve, and were used to assess the model’s accuracy in different ecosystems and land use types. Field data were also leveraged to identify additional data needs and other potential drivers of degradation not taken into account by the model. The accuracy assessment showed that while the Advanced Spaceborne Thermal Emission and Reflection Radiometer Digital Elevation Model (ASTER DEM) was adequate for estimating slope and aspect, data sets used for estimating vegetative cover and soil properties were unable to capture spatial heterogeneity seen in the field. A correlation analysis among field data suggested that topographic forcing was a major driver of degradation, but discrepancies between modelled and observed field condition suggested that the effects anthropogenic factors need to be better accounted for in order to improve the model’s accuracy. The integration of a supervised land cover classification with a soil erosion and deposition model allows for areas at risk for degradation due to topographic forcing to be identified for further analysis and monitoring. Additional research is needed to predict soil properties and vegetative cover at a higher spatial resolution to better understand their influence on rangeland condition as well as to further investigate other drivers of degradation.




GIS, Rangeland Degradation, RUSLE, USPED


Western Washington University

OCLC Number


Subject – LCSH

Range management--Risk assessment--Peru--Cordillera Central; Soil erosion--Risk assessment--Peru--Cordillera Central; Soil erosion--Peru--Cordillera Central--Remote sensing

Geographic Coverage

Cordillera Central (Peru)




masters theses




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