The increased variety of satellite remote sensing platforms creates opportunities for estimating ... more The increased variety of satellite remote sensing platforms creates opportunities for estimating tropical forest diversity needed for environmental decision-making. As little as 10% of the original seasonally dry tropical forest (SDTF) remains for Ecuador, Peru, and Colombia. Remnant forests show high rates of species endemism, but experience degradation from climate change, wood-cutting, and livestock-grazing. Forest census data provide a vital resource for examining remote sensing methods to estimate diversity levels. We used spatially referenced trees ≥5 cm in diameter and simulated 0.10 ha plots measured from a 9 ha SDTF in southwestern Ecuador to compare machine learning (ML) models for six α-diversity indices. We developed 1 m tree canopy height and elevation models from stem mapped trees, at a scale conventionally derived from light detection and ranging (LiDAR). We then used an ensemble ML approach comparing single- and combined-sensor models from RapidEye, Sentinel-2 and in...
The increased variety of satellite remote sensing platforms creates opportunities for estimating ... more The increased variety of satellite remote sensing platforms creates opportunities for estimating tropical forest diversity needed for environmental decision-making. As little as 10% of the original seasonally dry tropical forest (SDTF) remains for Ecuador, Peru, and Colombia. Remnant forests show high rates of species endemism, but experience degradation from climate change, wood-cutting, and livestock-grazing. Forest census data provide a vital resource for examining remote sensing methods to estimate diversity levels. We used spatially referenced trees ≥5 cm in diameter and simulated 0.10 ha plots measured from a 9 ha SDTF in southwestern Ecuador to compare machine learning (ML) models for six α-diversity indices. We developed 1 m tree canopy height and elevation models from stem mapped trees, at a scale conventionally derived from light detection and ranging (LiDAR). We then used an ensemble ML approach comparing single- and combined-sensor models from RapidEye, Sentinel-2 and in...
The increased variety of satellite remote sensing platforms creates opportunities for estimating ... more The increased variety of satellite remote sensing platforms creates opportunities for estimating tropical forest diversity needed for environmental decision-making. As little as 10% of the original seasonally dry tropical forest (SDTF) remains for Ecuador, Peru, and Colombia. Remnant forests show high rates of species endemism, but experience degradation from climate change, wood-cutting, and livestock-grazing. Forest census data provide a vital resource for examining remote sensing methods to estimate diversity levels. We used spatially referenced trees ≥5 cm in diameter and simulated 0.10 ha plots measured from a 9 ha SDTF in southwestern Ecuador to compare machine learning (ML) models for six α-diversity indices. We developed 1 m tree canopy height and elevation models from stem mapped trees, at a scale conventionally derived from light detection and ranging (LiDAR). We then used an ensemble ML approach comparing single- and combined-sensor models from RapidEye, Sentinel-2 and in...
Monitoring waterfowl numbers during primary migration and winter periods is essential to developi... more Monitoring waterfowl numbers during primary migration and winter periods is essential to developing effective habitat conservation and management strategies. The relationship between available habitat and waterfowl numbers obtained from aerial survey transects is not well studied. To determine these relationships, multispectral SPOT-5 satellite imagery acquired for Sequoyah National Wildlife Refuge close to the time of waterfowl surveys was used to map habitat conditions. Robust Random Forest classification trees were used to model 16 land cover types using 416 reference locations collected in the field or derived from aerial photos close to or during waterfowl survey dates. The normalized difference vegetation index (NDVI), normalized difference water index (NDWI) and a simple ratio (SR) of red and near infrared bands were used to enhance classification accuracy for key habitat areas and abundance of water. Terrain variables such as slope, solar illumination and cosine transformed ...
Forest management to restore fire-adapted ponderosa pine ecosystems is a central priority of the ... more Forest management to restore fire-adapted ponderosa pine ecosystems is a central priority of the Southwestern Region of the USDA Forest Service. Appropriately-scaled businesses are apt to play a key role in achieving this goal by harvesting, processing and selling wood products, thereby reducing treatment costs and providing economic opportunities. The manner in which treatments occur across northern Arizona, with its multiple jurisdictions and land management areas, is of vital concern to a diversity of stakeholder groups. To identify a level of forest thinning treatments and potential wood supply from restoration byproducts, a 20-member working group representing environmental non-governmental organizations (NGOs), private forest industries, local government, the Ecological Restoration Institute at Northern Arizona University (NAU), and state and federal land and resource management agencies was assembled. A series of seven workshops supported by Forest Ecosystem Restoration Analy...
Tropical dry and deciduous forest comprises as much as 42% of the world’s tropical forests, but h... more Tropical dry and deciduous forest comprises as much as 42% of the world’s tropical forests, but has received far less attention than forest in wet tropical areas. Land use change threatens to greatly reduce the extent of dry forest that is known to contain high levels of plant and animal diversity. Forest fragmentation may further endanger arboreal mammals that play principal role in the dispersal of large seeded fruits, plant community assembly and diversity in these systems. Data on the spatial arrangement and extent of dry forest and other land cover types is greatly needed to enhance studies of forest fragmentation effects on animal populations. To address this issue, we compared two Random Forest decision tree models for land cover classification in a Nicaraguan tropical dry forest landscape with and without the use of terrain variables derived from Space Shuttle Radar and Topography Mission digital elevation data (SRTM-DEM). Landsat Enhanced Thematic Mapper (ETM+) bands and ve...
1 Grupo Bosques, Áreas Protegidas y Biodiversidad, CATIE, Turrialba, 7170. Costa Rica. bfinegan@c... more 1 Grupo Bosques, Áreas Protegidas y Biodiversidad, CATIE, Turrialba, 7170. Costa Rica. bfinegan@catie.ac.cr 2 WWF-Perú cespedes@catie.ac.cr Northern Arizona University. ssesnie@catie.ac.cr 4 Director Programa de Ciencias, TNC. San José, Costa Rica. bherrera@tnc.org 5 SINAC/MINAE. gustavo.induni@sinac.go.cr ICOMVIS/UNA. jsaenz@una.ac.cr 7 INBIO. jugalde@inbio.ac.cr 8 ICOMVIS/UNA. gwongr@racsa.co.cr Bryan Finegan ; Margarita Céspedes Agüero ; Steven E. Sesnie3; Bernal Herrera4; Gustavo Induni5; Joel Sáenz6; Jesús Ugalde7; Grace Wong8
Thinning treatments focused on small-diameter trees have been designed to restore fire-adapted po... more Thinning treatments focused on small-diameter trees have been designed to restore fire-adapted ponderosa pine ecosystems. Estimating the volume of wood byproducts derived from treatments can assist with agency planning of multiyear thinning contracts that sustain existing and attract new wood product businesses. Agency, local government, industry, and environmental representatives were engaged to assess the level of agreement on restoration treatments in northern Arizona. Participants unanimously agreed on appropriate management across two-thirds of the 2.4 million ac analysis area and defined desired posttreatment conditions using forest structure information derived from remotely sensed data. Results indicate that an estimated 850 million ft 3 of stem volume and 8.0 million green tn of tree crown biomass could be generated from tree thinning to reestablish fire-adapted conditions and stimulate new economic opportunities while meeting social and environmental criteria. Wood supply ...
: This research sought to integrate empirically based models of non-native plant invasion, fire, ... more : This research sought to integrate empirically based models of non-native plant invasion, fire, and wildlife habitat in a spatially explicit decision-support package that informs sustainable resource management and recovery of native habitats and species in the face of ongoing climate change. We modeled distribution, biomass, invasion risk, and fire risk associated with five nonnative invasive plant species on two military installations, two refuges, and one National Monument in the Sonoran Desert of Arizona. Research involved extensive field sampling efforts to train and test regional- and landscape-scale models of nonnative invasive plant distribution and biomass. Species-specific models incorporated novel remote sensing techniques that identified targets based on both phenological and spectral differences using satellite platforms of differing spatial, temporal,and spectral resolutions. During this project, detections of Sahara mustard and Schismus spp. were relatively common ac...
The spread of flammable invasive grasses, woody plant encroachment, and enhanced aridity have int... more The spread of flammable invasive grasses, woody plant encroachment, and enhanced aridity have interacted in many grasslands globally to increase wildfire activity and risk to valued assets. Annual variation in the abundance and distribution of fine-fuel present challenges to land managers implementing prescribed burns and mitigating wildfire, although methods to produce high-resolution fuel estimates are still under development. To further understand how prescribed fire and wildfire influence fine-fuels in a semi-arid grassland invaded by non-native perennial grasses, we combined high-resolution Sentinel-2A imagery with in situ vegetation data and machine learning to estimate yearly fine-fuel loads from 2015 to 2020. The resulting model of fine-fuel corresponded to field-based validation measurements taken in the first (R2 = 0.52, RMSE = 218 kg/ha) and last year (R2 = 0.63, RMSE = 196 kg/ha) of this 6-year study. Serial prediction of the fine-fuel model allowed for an assessment of ...
Fire has historically played an important role in shaping the structure and composition of Sonora... more Fire has historically played an important role in shaping the structure and composition of Sonoran semi-desert grassland vegetation. Yet, human use and land management activities have significantly altered arid grassland ecosystems over the last century, often producing novel fuel conditions. The variety of continuously updated satellite remote sensing systems provide opportunities for efficiently mapping combustible fine-fuels and fuel-types (e.g., grass, shrub, or tree cover) over large landscapes that are helpful for evaluating fire hazard and risk. For this study, we compared field ceptometer leaf area index (LAI) measurements to conventional means for estimating fine-fuel biomass on 20, 50 m × 20 m plots and 431, 0.5 m × 0.5 m quadrats on the Buenos Aires National Wildlife Refuge (BANWR) in southern Arizona. LAI explained 65% of the variance in fine-fuel biomass using simple linear regression. An additional 19% of variance was explained from Random Forest regression tree models...
The increased variety of satellite remote sensing platforms creates opportunities for estimating ... more The increased variety of satellite remote sensing platforms creates opportunities for estimating tropical forest diversity needed for environmental decision-making. As little as 10% of the original seasonally dry tropical forest (SDTF) remains for Ecuador, Peru, and Colombia. Remnant forests show high rates of species endemism, but experience degradation from climate change, wood-cutting, and livestock-grazing. Forest census data provide a vital resource for examining remote sensing methods to estimate diversity levels. We used spatially referenced trees ≥5 cm in diameter and simulated 0.10 ha plots measured from a 9 ha SDTF in southwestern Ecuador to compare machine learning (ML) models for six α-diversity indices. We developed 1 m tree canopy height and elevation models from stem mapped trees, at a scale conventionally derived from light detection and ranging (LiDAR). We then used an ensemble ML approach comparing single- and combined-sensor models from RapidEye, Sentinel-2 and in...
The increased variety of satellite remote sensing platforms creates opportunities for estimating ... more The increased variety of satellite remote sensing platforms creates opportunities for estimating tropical forest diversity needed for environmental decision-making. As little as 10% of the original seasonally dry tropical forest (SDTF) remains for Ecuador, Peru, and Colombia. Remnant forests show high rates of species endemism, but experience degradation from climate change, wood-cutting, and livestock-grazing. Forest census data provide a vital resource for examining remote sensing methods to estimate diversity levels. We used spatially referenced trees ≥5 cm in diameter and simulated 0.10 ha plots measured from a 9 ha SDTF in southwestern Ecuador to compare machine learning (ML) models for six α-diversity indices. We developed 1 m tree canopy height and elevation models from stem mapped trees, at a scale conventionally derived from light detection and ranging (LiDAR). We then used an ensemble ML approach comparing single- and combined-sensor models from RapidEye, Sentinel-2 and in...
The increased variety of satellite remote sensing platforms creates opportunities for estimating ... more The increased variety of satellite remote sensing platforms creates opportunities for estimating tropical forest diversity needed for environmental decision-making. As little as 10% of the original seasonally dry tropical forest (SDTF) remains for Ecuador, Peru, and Colombia. Remnant forests show high rates of species endemism, but experience degradation from climate change, wood-cutting, and livestock-grazing. Forest census data provide a vital resource for examining remote sensing methods to estimate diversity levels. We used spatially referenced trees ≥5 cm in diameter and simulated 0.10 ha plots measured from a 9 ha SDTF in southwestern Ecuador to compare machine learning (ML) models for six α-diversity indices. We developed 1 m tree canopy height and elevation models from stem mapped trees, at a scale conventionally derived from light detection and ranging (LiDAR). We then used an ensemble ML approach comparing single- and combined-sensor models from RapidEye, Sentinel-2 and in...
Monitoring waterfowl numbers during primary migration and winter periods is essential to developi... more Monitoring waterfowl numbers during primary migration and winter periods is essential to developing effective habitat conservation and management strategies. The relationship between available habitat and waterfowl numbers obtained from aerial survey transects is not well studied. To determine these relationships, multispectral SPOT-5 satellite imagery acquired for Sequoyah National Wildlife Refuge close to the time of waterfowl surveys was used to map habitat conditions. Robust Random Forest classification trees were used to model 16 land cover types using 416 reference locations collected in the field or derived from aerial photos close to or during waterfowl survey dates. The normalized difference vegetation index (NDVI), normalized difference water index (NDWI) and a simple ratio (SR) of red and near infrared bands were used to enhance classification accuracy for key habitat areas and abundance of water. Terrain variables such as slope, solar illumination and cosine transformed ...
Forest management to restore fire-adapted ponderosa pine ecosystems is a central priority of the ... more Forest management to restore fire-adapted ponderosa pine ecosystems is a central priority of the Southwestern Region of the USDA Forest Service. Appropriately-scaled businesses are apt to play a key role in achieving this goal by harvesting, processing and selling wood products, thereby reducing treatment costs and providing economic opportunities. The manner in which treatments occur across northern Arizona, with its multiple jurisdictions and land management areas, is of vital concern to a diversity of stakeholder groups. To identify a level of forest thinning treatments and potential wood supply from restoration byproducts, a 20-member working group representing environmental non-governmental organizations (NGOs), private forest industries, local government, the Ecological Restoration Institute at Northern Arizona University (NAU), and state and federal land and resource management agencies was assembled. A series of seven workshops supported by Forest Ecosystem Restoration Analy...
Tropical dry and deciduous forest comprises as much as 42% of the world’s tropical forests, but h... more Tropical dry and deciduous forest comprises as much as 42% of the world’s tropical forests, but has received far less attention than forest in wet tropical areas. Land use change threatens to greatly reduce the extent of dry forest that is known to contain high levels of plant and animal diversity. Forest fragmentation may further endanger arboreal mammals that play principal role in the dispersal of large seeded fruits, plant community assembly and diversity in these systems. Data on the spatial arrangement and extent of dry forest and other land cover types is greatly needed to enhance studies of forest fragmentation effects on animal populations. To address this issue, we compared two Random Forest decision tree models for land cover classification in a Nicaraguan tropical dry forest landscape with and without the use of terrain variables derived from Space Shuttle Radar and Topography Mission digital elevation data (SRTM-DEM). Landsat Enhanced Thematic Mapper (ETM+) bands and ve...
1 Grupo Bosques, Áreas Protegidas y Biodiversidad, CATIE, Turrialba, 7170. Costa Rica. bfinegan@c... more 1 Grupo Bosques, Áreas Protegidas y Biodiversidad, CATIE, Turrialba, 7170. Costa Rica. bfinegan@catie.ac.cr 2 WWF-Perú cespedes@catie.ac.cr Northern Arizona University. ssesnie@catie.ac.cr 4 Director Programa de Ciencias, TNC. San José, Costa Rica. bherrera@tnc.org 5 SINAC/MINAE. gustavo.induni@sinac.go.cr ICOMVIS/UNA. jsaenz@una.ac.cr 7 INBIO. jugalde@inbio.ac.cr 8 ICOMVIS/UNA. gwongr@racsa.co.cr Bryan Finegan ; Margarita Céspedes Agüero ; Steven E. Sesnie3; Bernal Herrera4; Gustavo Induni5; Joel Sáenz6; Jesús Ugalde7; Grace Wong8
Thinning treatments focused on small-diameter trees have been designed to restore fire-adapted po... more Thinning treatments focused on small-diameter trees have been designed to restore fire-adapted ponderosa pine ecosystems. Estimating the volume of wood byproducts derived from treatments can assist with agency planning of multiyear thinning contracts that sustain existing and attract new wood product businesses. Agency, local government, industry, and environmental representatives were engaged to assess the level of agreement on restoration treatments in northern Arizona. Participants unanimously agreed on appropriate management across two-thirds of the 2.4 million ac analysis area and defined desired posttreatment conditions using forest structure information derived from remotely sensed data. Results indicate that an estimated 850 million ft 3 of stem volume and 8.0 million green tn of tree crown biomass could be generated from tree thinning to reestablish fire-adapted conditions and stimulate new economic opportunities while meeting social and environmental criteria. Wood supply ...
: This research sought to integrate empirically based models of non-native plant invasion, fire, ... more : This research sought to integrate empirically based models of non-native plant invasion, fire, and wildlife habitat in a spatially explicit decision-support package that informs sustainable resource management and recovery of native habitats and species in the face of ongoing climate change. We modeled distribution, biomass, invasion risk, and fire risk associated with five nonnative invasive plant species on two military installations, two refuges, and one National Monument in the Sonoran Desert of Arizona. Research involved extensive field sampling efforts to train and test regional- and landscape-scale models of nonnative invasive plant distribution and biomass. Species-specific models incorporated novel remote sensing techniques that identified targets based on both phenological and spectral differences using satellite platforms of differing spatial, temporal,and spectral resolutions. During this project, detections of Sahara mustard and Schismus spp. were relatively common ac...
The spread of flammable invasive grasses, woody plant encroachment, and enhanced aridity have int... more The spread of flammable invasive grasses, woody plant encroachment, and enhanced aridity have interacted in many grasslands globally to increase wildfire activity and risk to valued assets. Annual variation in the abundance and distribution of fine-fuel present challenges to land managers implementing prescribed burns and mitigating wildfire, although methods to produce high-resolution fuel estimates are still under development. To further understand how prescribed fire and wildfire influence fine-fuels in a semi-arid grassland invaded by non-native perennial grasses, we combined high-resolution Sentinel-2A imagery with in situ vegetation data and machine learning to estimate yearly fine-fuel loads from 2015 to 2020. The resulting model of fine-fuel corresponded to field-based validation measurements taken in the first (R2 = 0.52, RMSE = 218 kg/ha) and last year (R2 = 0.63, RMSE = 196 kg/ha) of this 6-year study. Serial prediction of the fine-fuel model allowed for an assessment of ...
Fire has historically played an important role in shaping the structure and composition of Sonora... more Fire has historically played an important role in shaping the structure and composition of Sonoran semi-desert grassland vegetation. Yet, human use and land management activities have significantly altered arid grassland ecosystems over the last century, often producing novel fuel conditions. The variety of continuously updated satellite remote sensing systems provide opportunities for efficiently mapping combustible fine-fuels and fuel-types (e.g., grass, shrub, or tree cover) over large landscapes that are helpful for evaluating fire hazard and risk. For this study, we compared field ceptometer leaf area index (LAI) measurements to conventional means for estimating fine-fuel biomass on 20, 50 m × 20 m plots and 431, 0.5 m × 0.5 m quadrats on the Buenos Aires National Wildlife Refuge (BANWR) in southern Arizona. LAI explained 65% of the variance in fine-fuel biomass using simple linear regression. An additional 19% of variance was explained from Random Forest regression tree models...
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