Presentations

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Open Access
Application of Landsat 8 imagery and statistical models for mapping critical headwater wetlands of Ethiopia
(Colorado State Univesity. Libraries, 2014) Chignell, Stephen, author; Anderson, Ryan, author; Wakie, Tewodros, author
The Bale Mountains of south-central Ethiopia comprise one of Africa's least-studied massifs, and are home to the world-renowned Bale Mountain National Park. A designated Biodiversity Hotspot, the area also serves as the headwaters for five major rivers that flow out of the mountains, supporting 12 million people in the arid lowlands to the east. In recent years, development in the surrounding area has forced many agro-pastoralists into the highlands, and approximately 40,000 people now live within the park boundaries. Mapping the location and extent of the region's water resources has been identified as a key research need for local park officials and conservation groups as they work to sustainably accommodate this massive influx of people and livestock. Of particular concern are the region's numerous alpine lakes and wetlands, as they are essential for wildlife habitat, water quality, and discharge timing for both upstream and downstream users throughout the dry season. This study used environmental indices derived from Landsat 8 Operational Land Imager/Thermal Infrared data, topographic variables, and species distribution models to map all perennial alpine lakes and wetlands in the Bale Mountains. Resulting models of wetlands and lakes had classification accuracies of 97% and 100%, respectively. These represent the first comprehensive maps of their kind in Bale, and will facilitate the targeting of conservation and research efforts in the region. Additionally, the methodology is applicable in other remote areas around the world where field data is sparse and regular monitoring is needed.
Open Access
Application of Landsat 8 imagery and statistical models for mapping critical headwater wetlands of Ethiopia
(Colorado State Univesity. Libraries, 2014) Chignell, Stephen, author; Anderson, Ryan, author; Wakie, Tewodros, author
The Bale Mountains of south-central Ethiopia comprise one of Africa's least-studied massifs, and are home to the world-renowned Bale Mountain National Park. A designated Biodiversity Hotspot, the area also serves as the headwaters for five major rivers that flow out of the mountains, supporting 12 million people in the arid lowlands to the east. In recent years, development in the surrounding area has forced many agro-pastoralists into the highlands, and approximately 40,000 people now live within the park boundaries. Mapping the location and extent of the region's water resources has been identified as a key research need for local park officials and conservation groups as they work to sustainably accommodate this massive influx of people and livestock. Of particular concern are the region's numerous alpine lakes and wetlands, as they are essential for wildlife habitat, water quality, and discharge timing for both upstream and downstream users throughout the dry season. This study used environmental indices derived from Landsat 8 Operational Land Imager/Thermal Infrared data, topographic variables, and species distribution models to map all perennial alpine lakes and wetlands in the Bale Mountains. Resulting models of wetlands and lakes had classification accuracies of 97% and 100%, respectively. These represent the first comprehensive maps of their kind in Bale, and will facilitate the targeting of conservation and research efforts in the region. Additionally, the methodology is applicable in other remote areas around the world where field data is sparse and regular monitoring is needed.
Open Access
Mapping four decades of fire history for targeted conservation in the south-central highlands of Ethiopia
(Colorado State Univesity. Libraries, 2015) Chignell, Stephen, author; Fowler, Chandra, author; Hopping, Kelly, author; Schulte, Darin, author
The Bale Mountains of south-central Ethiopia comprise one of the largest and least studied mountain systems in Africa. An internationally recognized biodiversity hotspot, the region is home to Bale Mountains National Park and the Sanetti Plateau, which provide critical alpine habitat for numerous endemic and endangered species, such as the mountain nyala. Ethiopian agro-pastoralists in the region practice intentional burning to clear land for grazing and planting; however, pressures related to climate change and increasing populations have made understanding the frequency and extent of burning a top priority for conservationists and land managers seeking to balance conservation goals with the needs of local communities. To address this need, we mapped historical fire extent and frequency in the unique, high-altitude Ericaceous shrublands of Bale, using all available dry-season scenes from 42 years (1973-2015) of the Landsat record. We spatially and spectrally linked imagery within the LandsatLinkr R package to visualize landscape disturbances with a tasseled cap time series. A quantitative assessment of burned areas derived from the normalized burn ratio found that nearly all Ericaceous vegetation in the study area has burned since 1995, but with few repeated fires in the same location. Our results were not only in agreement with two MODIS Burned Area products and fire records compiled from the literature, but also improved upon their spatial resolution and augmented their temporal record. Maps and spatial data of fire date, extent, and frequency were disseminated to partners working in Ethiopia. These will support detailed studies of fire ecology in Bale and inform management approaches that ensure the preservation of the region's natural resources and the social-ecological systems they support.
Open Access
Mapping four decades of fire history for targeted conservation in the south-central highlands of Ethiopia
(Colorado State Univesity. Libraries, 2015) Chignell, Stephen, author; Fowler, Chandra, author; Hopping, Kelly, author; Schulte, Darin, author
The Bale Mountains of south-central Ethiopia comprise one of the largest and least studied mountain systems in Africa. An internationally recognized biodiversity hotspot, the region is home to Bale Mountains National Park and the Sanetti Plateau, which provide critical alpine habitat for numerous endemic and endangered species, such as the mountain nyala. Ethiopian agro-pastoralists in the region practice intentional burning to clear land for grazing and planting; however, pressures related to climate change and increasing populations have made understanding the frequency and extent of burning a top priority for conservationists and land managers seeking to balance conservation goals with the needs of local communities. To address this need, we mapped historical fire extent and frequency in the unique, high-altitude Ericaceous shrublands of Bale, using all available dry-season scenes from 42 years (1973-2015) of the Landsat record. We spatially and spectrally linked imagery within the LandsatLinkr R package to visualize landscape disturbances with a tasseled cap time series. A quantitative assessment of burned areas derived from the normalized burn ratio found that nearly all Ericaceous vegetation in the study area has burned since 1995, but with few repeated fires in the same location. Our results were not only in agreement with two MODIS Burned Area products and fire records compiled from the literature, but also improved upon their spatial resolution and augmented their temporal record. Maps and spatial data of fire date, extent, and frequency were disseminated to partners working in Ethiopia. These will support detailed studies of fire ecology in Bale and inform management approaches that ensure the preservation of the region's natural resources and the social-ecological systems they support.

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