Stephen Trombulak - Academia.edu (original) (raw)
Papers by Stephen Trombulak
Landscape-scale Conservation Planning, 2010
... Over the past 9 years, this group of conservation scientists has worked to realize the vision... more ... Over the past 9 years, this group of conservation scientists has worked to realize the vision of the conservation collaborative by developing spatially ... Great Barrier Reef Marine Park Authority (nd). ... Drafting a conservation blueprint: A practitioner's guide to planning for biodiversity. ...
Landscape-scale Conservation Planning, 2010
Measuring and mapping human influence at the global scale suffers from problems of accuracy and r... more Measuring and mapping human influence at the global scale suffers from problems of accuracy and resolution. To evaluate the magnitude of this problem we mapped the Human Footprint (HF) for the Northern Appalachian/Acadian ecoregion at a 90-m resolution using best available data on human settlement, access, land use change, and electrical power infrastructure. Such a map measures the magnitude of human transformation of a landscape, scaled between Human Footprint scores of 0 and 100. Comparison with a 1-km resolution Global Human Footprint map revealed similar spatial patterns of human influence. The correlation between HF scores, however, declined with the size of the area compared, with the rank correlation between ecoregional and global HF scores ranging between 0.67 for 100% of the ecoregion and 0.41 for 0.1% of the ecoregion. This indicates that rescaling the map to a finer resolution leads to improvements that increase as the planning area becomes smaller. The map reveals that 46% of the ecoregion has HF ≤ 20 (compared to 59% in the global analysis) and 34% had HF > 40 (compared to 21% in the global analysis). These results demonstrate the benefit of performing region-scale Human Footprint mapping to support conservation-based land use planning at the ecoregional to the local scale. This exercise also provides a data framework with which to model regionally plausible Future Human Footprint scenarios. These and other benefits of producing a regional-scale Human Footprint must be carefully weighed against the costs involved, in light of the region's conservation planning needs.
Environmental History, 2002
Conservation Biology, 2007
The Osteoarthritis Initiative (OAI) is a multi-center, longitudinal study aimed at assessing biom... more The Osteoarthritis Initiative (OAI) is a multi-center, longitudinal study aimed at assessing biomarkers in osteoarthritis (OA) including those derived from magnetic resonance (MR) imaging. The MR images from the OAI can be used to quantify cartilage parameters such as thickness and T 2 relaxation time. Cartilage T 2 relaxation time is sensitive to biochemical composition, collagen damage, and tissue hydration, and may therefore be an important marker for cartilage degeneration. The purpose of this study is to [1] examine changes in MR knee cartilage parameters including thickness, T 2 , and spatial distribution of cartilage T 2 and [2] examine whether these baseline MR parameters predict change in knee pain.
Climate and Conservation, 2012
Landscape-scale Conservation Planning, 2010
Nature reserves increasingly function as islands in a human-dominated matrix. Habitat conservatio... more Nature reserves increasingly function as islands in a human-dominated matrix. Habitat conservation initiatives that seek to reconnect patches using functional corridors are increasingly part and parcel of conservation planning projects. Numerous methods have evolved all based on similar of least cost paths, functional rather than structural connectivity, and landscape resistance. However significant differences in approach exist including whether a network of patches is considered simultaneously or as patch-patch pairs, and whether the goal is to model spatially explicit corridors or movement bottlenecks. We review these approaches and then describe ecological connectivity modeling for an ecoregion using the graphtheoretic approach considering two different patch-node scenarios, at the ecoregion scale and apply a more localized connectivity modeling exercise for a subregion and a single focal species the American Black bear (Ursus americanus). We discuss the difficulties of attempting to model functional corridors for focal species over heterogenous landscapes, and the potential benefits of using 'naturalness' or Human Footprint surrogates for connectivity.
Oecologia, 1979
The foraging strategies of four naturally co-existing heteromyid rodent species were investigated... more The foraging strategies of four naturally co-existing heteromyid rodent species were investigated: Dipodomys deserti (˜100 g), D. merriami (˜38 g), Microdipodops pallidus (˜13 g), and Perognathus longimembris (˜7 g). In 208 over-night laboratory foraging trials animals were provided with millet seed distributed in clumped and scattered patterns. Net removal of seeds from the foraging arena and amounts of seeds in
Northeastern Naturalist, 2009
Northeastern Naturalist, 2001
We report the results of all readily available inventories of wintering bats in Vermont. Surveys ... more We report the results of all readily available inventories of wintering bats in Vermont. Surveys at 23 hibernacula were compiled from the literature and unpublished data of numerous biologists and cavers. The earliest Vermont records date back to 1934. Only five hibernacula were systematically surveyed for more than 45 years. Despite data limitations, several trends have emerged. Since the 1930s, wintering populations of Myotis sodalis have dramatically declined; wintering populations of M. lucifugus have increased; and wintering populations of all other Vermont species (M. leibii, M. septentrionalis, Eptesicus fuscus, and Pipistrellus subflavus) have remained small.
Marine Policy, 2012
Marine Protected Areas (MPAs) are an important tool for the conservation of marine species and ec... more Marine Protected Areas (MPAs) are an important tool for the conservation of marine species and ecosystems. Yet despite the significant differences between marine and terrestrial systems in terms of their critical ecological processes, stresses, and relationships with cultural systems, methods used to characterize levels of protection for biological diversity in MPAs are all derived from schemes developed for terrestrial systems. A new system designed to classify levels of protection in MPAs is proposed, based on criteria specifically ...
Landscape and Urban Planning, 2009
Conversion of relatively "wild" areas constitutes a rising threat to the ecological integrity of ... more Conversion of relatively "wild" areas constitutes a rising threat to the ecological integrity of North American landscapes. As developers seek unprotected, amenity-rich lands, conservation planners require methods to recognize risk and prioritize actions. Most development models and processes are incremental, accumulating change over time and space. By contrast, large-scale amenity development can be rapid and extensive, necessitating "rapid assessment" techniques. For undeveloped lakeshores in the Northern Appalachian/Acadian ecoregion (330 000 km 2 ), we developed a geospatial screening process based on four factors: (1) urban area proximity, (2) attractiveness of amenity (size), (3) regulatory gaps in protection, and (4) likelihood that owners will develop. To assess conversion risk, we added developable zones to the 10 783 large lakes and ponds in the ecoregion and assessed risk to these lands based on four factors at two distances from 15 major urban areas in the region. Thirty-eight of 387 landowners were classified most likely to convert their lands through development, and 11 of these accounted for 97.5% of the total high-risk habitat area (625-1118 km 2 ). Nearly all of the at-risk land (94.6%) lay outside of currently settled areas and most (69.1%) under the purview of a single regulatory agency, the Land Use Regulatory Commission of Maine (LURC). Without rigorous planning by such agencies large-scale, highly dispersed, and rapid conversion of lightly settled, amenity-rich forestland threatens habitat degradation at multiple spatial scales, i.e., local ecosystems themselves (e.g., lakes), surrounding landscapes, and regions.
Landscape and Urban Planning, 2008
Measuring and mapping human influence at the global scale suffers from problems of accuracy and r... more Measuring and mapping human influence at the global scale suffers from problems of accuracy and resolution. To evaluate the magnitude of this problem we mapped the Human Footprint (HF) for the Northern Appalachian/Acadian ecoregion at a 90-m resolution using best available data on human settlement, access, land use change, and electrical power infrastructure. Such a map measures the magnitude of human transformation of a landscape, scaled between Human Footprint scores of 0 and 100. Comparison with a 1-km resolution Global Human Footprint map revealed similar spatial patterns of human influence. The correlation between HF scores, however, declined with the size of the area compared, with the rank correlation between ecoregional and global HF scores ranging between 0.67 for 100% of the ecoregion and 0.41 for 0.1% of the ecoregion. This indicates that rescaling the map to a finer resolution leads to improvements that increase as the planning area becomes smaller. The map reveals that 46% of the ecoregion has HF ≤ 20 (compared to 59% in the global analysis) and 34% had HF > 40 (compared to 21% in the global analysis). These results demonstrate the benefit of performing region-scale Human Footprint mapping to support conservation-based land use planning at the ecoregional to the local scale. This exercise also provides a data framework with which to model regionally plausible Future Human Footprint scenarios. These and other benefits of producing a regional-scale Human Footprint must be carefully weighed against the costs involved, in light of the region's conservation planning needs.
Landscape and Urban Planning, 2007
Existing roads have far-reaching effects on biodiversity, and therefore road network expansion is... more Existing roads have far-reaching effects on biodiversity, and therefore road network expansion is of critical concern to conservation planning. Road density trend analysis is often too coarse and assumes homogeneous landscapes, whereas spatial transition probability analysis captures landscape variability typical of ecoregions. Simple models for projecting road network growth will assist planning agencies and conservation organizations to guide protection efforts. We investigate growth of regular public roads in the State of Maine over a 17-year historical period, and then use the best-selected (AIC) logistic regression model to validate and then project spatial probability of future roads to the Northern Appalachian/Acadian ecoregion. Nearly 2000 km of new roads were constructed in settled landscapes in Maine 1986-2003, influencing 37,000 ha of adjacent habitats. The majority (93.5%) of the new roads performed local functions and were short (<1/3 km in length), characterized as residential roads typical of sprawl. The best-selected logit model [dwelling density (+), elevation (−), distance to urban area (−), distance to existing primary/secondary highway (−)] captured 84% of reserved new road points in Maine, and only 27% of random points at the >0.5 probability level. The projected model forecasts 0.5 million km of new residential public roads in the Northern Appalachian/Acadian ecoregion for the next two decades, suggesting that cumulative effects of residential road network expansion are a serious region-scale biodiversity threat.
Geophysical Research Letters, 2004
We have analyzed twentieth-century temperature data from 73 climate stations in New England and N... more We have analyzed twentieth-century temperature data from 73 climate stations in New England and New York. Linear regression gives a 100-year temperature change (ΔT100) for each station. All but two stations show an increase over this time, giving a regional area-weighted average ΔT100 of 1.11°C. Average ΔT100 values for each state are all positive, ranging from 0.86°C to 1.86°C. Spatial
Environmental History, 2002
Environmental History, 2000
... xii Acknowledgments College library; and Nancy Sherman, Vermont Public Service Department. ..... more ... xii Acknowledgments College library; and Nancy Sherman, Vermont Public Service Department. ... Portions of this book were read and edited by several people, to whom we are forever indebted: Jim Andrews, Ray Coish, Lucy Harding, Charles Johnson, Marc Lapin, Audi Lloyd ...
Landscape-scale Conservation Planning, 2010
... Over the past 9 years, this group of conservation scientists has worked to realize the vision... more ... Over the past 9 years, this group of conservation scientists has worked to realize the vision of the conservation collaborative by developing spatially ... Great Barrier Reef Marine Park Authority (nd). ... Drafting a conservation blueprint: A practitioner's guide to planning for biodiversity. ...
Landscape-scale Conservation Planning, 2010
Measuring and mapping human influence at the global scale suffers from problems of accuracy and r... more Measuring and mapping human influence at the global scale suffers from problems of accuracy and resolution. To evaluate the magnitude of this problem we mapped the Human Footprint (HF) for the Northern Appalachian/Acadian ecoregion at a 90-m resolution using best available data on human settlement, access, land use change, and electrical power infrastructure. Such a map measures the magnitude of human transformation of a landscape, scaled between Human Footprint scores of 0 and 100. Comparison with a 1-km resolution Global Human Footprint map revealed similar spatial patterns of human influence. The correlation between HF scores, however, declined with the size of the area compared, with the rank correlation between ecoregional and global HF scores ranging between 0.67 for 100% of the ecoregion and 0.41 for 0.1% of the ecoregion. This indicates that rescaling the map to a finer resolution leads to improvements that increase as the planning area becomes smaller. The map reveals that 46% of the ecoregion has HF ≤ 20 (compared to 59% in the global analysis) and 34% had HF > 40 (compared to 21% in the global analysis). These results demonstrate the benefit of performing region-scale Human Footprint mapping to support conservation-based land use planning at the ecoregional to the local scale. This exercise also provides a data framework with which to model regionally plausible Future Human Footprint scenarios. These and other benefits of producing a regional-scale Human Footprint must be carefully weighed against the costs involved, in light of the region's conservation planning needs.
Environmental History, 2002
Conservation Biology, 2007
The Osteoarthritis Initiative (OAI) is a multi-center, longitudinal study aimed at assessing biom... more The Osteoarthritis Initiative (OAI) is a multi-center, longitudinal study aimed at assessing biomarkers in osteoarthritis (OA) including those derived from magnetic resonance (MR) imaging. The MR images from the OAI can be used to quantify cartilage parameters such as thickness and T 2 relaxation time. Cartilage T 2 relaxation time is sensitive to biochemical composition, collagen damage, and tissue hydration, and may therefore be an important marker for cartilage degeneration. The purpose of this study is to [1] examine changes in MR knee cartilage parameters including thickness, T 2 , and spatial distribution of cartilage T 2 and [2] examine whether these baseline MR parameters predict change in knee pain.
Climate and Conservation, 2012
Landscape-scale Conservation Planning, 2010
Nature reserves increasingly function as islands in a human-dominated matrix. Habitat conservatio... more Nature reserves increasingly function as islands in a human-dominated matrix. Habitat conservation initiatives that seek to reconnect patches using functional corridors are increasingly part and parcel of conservation planning projects. Numerous methods have evolved all based on similar of least cost paths, functional rather than structural connectivity, and landscape resistance. However significant differences in approach exist including whether a network of patches is considered simultaneously or as patch-patch pairs, and whether the goal is to model spatially explicit corridors or movement bottlenecks. We review these approaches and then describe ecological connectivity modeling for an ecoregion using the graphtheoretic approach considering two different patch-node scenarios, at the ecoregion scale and apply a more localized connectivity modeling exercise for a subregion and a single focal species the American Black bear (Ursus americanus). We discuss the difficulties of attempting to model functional corridors for focal species over heterogenous landscapes, and the potential benefits of using 'naturalness' or Human Footprint surrogates for connectivity.
Oecologia, 1979
The foraging strategies of four naturally co-existing heteromyid rodent species were investigated... more The foraging strategies of four naturally co-existing heteromyid rodent species were investigated: Dipodomys deserti (˜100 g), D. merriami (˜38 g), Microdipodops pallidus (˜13 g), and Perognathus longimembris (˜7 g). In 208 over-night laboratory foraging trials animals were provided with millet seed distributed in clumped and scattered patterns. Net removal of seeds from the foraging arena and amounts of seeds in
Northeastern Naturalist, 2009
Northeastern Naturalist, 2001
We report the results of all readily available inventories of wintering bats in Vermont. Surveys ... more We report the results of all readily available inventories of wintering bats in Vermont. Surveys at 23 hibernacula were compiled from the literature and unpublished data of numerous biologists and cavers. The earliest Vermont records date back to 1934. Only five hibernacula were systematically surveyed for more than 45 years. Despite data limitations, several trends have emerged. Since the 1930s, wintering populations of Myotis sodalis have dramatically declined; wintering populations of M. lucifugus have increased; and wintering populations of all other Vermont species (M. leibii, M. septentrionalis, Eptesicus fuscus, and Pipistrellus subflavus) have remained small.
Marine Policy, 2012
Marine Protected Areas (MPAs) are an important tool for the conservation of marine species and ec... more Marine Protected Areas (MPAs) are an important tool for the conservation of marine species and ecosystems. Yet despite the significant differences between marine and terrestrial systems in terms of their critical ecological processes, stresses, and relationships with cultural systems, methods used to characterize levels of protection for biological diversity in MPAs are all derived from schemes developed for terrestrial systems. A new system designed to classify levels of protection in MPAs is proposed, based on criteria specifically ...
Landscape and Urban Planning, 2009
Conversion of relatively "wild" areas constitutes a rising threat to the ecological integrity of ... more Conversion of relatively "wild" areas constitutes a rising threat to the ecological integrity of North American landscapes. As developers seek unprotected, amenity-rich lands, conservation planners require methods to recognize risk and prioritize actions. Most development models and processes are incremental, accumulating change over time and space. By contrast, large-scale amenity development can be rapid and extensive, necessitating "rapid assessment" techniques. For undeveloped lakeshores in the Northern Appalachian/Acadian ecoregion (330 000 km 2 ), we developed a geospatial screening process based on four factors: (1) urban area proximity, (2) attractiveness of amenity (size), (3) regulatory gaps in protection, and (4) likelihood that owners will develop. To assess conversion risk, we added developable zones to the 10 783 large lakes and ponds in the ecoregion and assessed risk to these lands based on four factors at two distances from 15 major urban areas in the region. Thirty-eight of 387 landowners were classified most likely to convert their lands through development, and 11 of these accounted for 97.5% of the total high-risk habitat area (625-1118 km 2 ). Nearly all of the at-risk land (94.6%) lay outside of currently settled areas and most (69.1%) under the purview of a single regulatory agency, the Land Use Regulatory Commission of Maine (LURC). Without rigorous planning by such agencies large-scale, highly dispersed, and rapid conversion of lightly settled, amenity-rich forestland threatens habitat degradation at multiple spatial scales, i.e., local ecosystems themselves (e.g., lakes), surrounding landscapes, and regions.
Landscape and Urban Planning, 2008
Measuring and mapping human influence at the global scale suffers from problems of accuracy and r... more Measuring and mapping human influence at the global scale suffers from problems of accuracy and resolution. To evaluate the magnitude of this problem we mapped the Human Footprint (HF) for the Northern Appalachian/Acadian ecoregion at a 90-m resolution using best available data on human settlement, access, land use change, and electrical power infrastructure. Such a map measures the magnitude of human transformation of a landscape, scaled between Human Footprint scores of 0 and 100. Comparison with a 1-km resolution Global Human Footprint map revealed similar spatial patterns of human influence. The correlation between HF scores, however, declined with the size of the area compared, with the rank correlation between ecoregional and global HF scores ranging between 0.67 for 100% of the ecoregion and 0.41 for 0.1% of the ecoregion. This indicates that rescaling the map to a finer resolution leads to improvements that increase as the planning area becomes smaller. The map reveals that 46% of the ecoregion has HF ≤ 20 (compared to 59% in the global analysis) and 34% had HF > 40 (compared to 21% in the global analysis). These results demonstrate the benefit of performing region-scale Human Footprint mapping to support conservation-based land use planning at the ecoregional to the local scale. This exercise also provides a data framework with which to model regionally plausible Future Human Footprint scenarios. These and other benefits of producing a regional-scale Human Footprint must be carefully weighed against the costs involved, in light of the region's conservation planning needs.
Landscape and Urban Planning, 2007
Existing roads have far-reaching effects on biodiversity, and therefore road network expansion is... more Existing roads have far-reaching effects on biodiversity, and therefore road network expansion is of critical concern to conservation planning. Road density trend analysis is often too coarse and assumes homogeneous landscapes, whereas spatial transition probability analysis captures landscape variability typical of ecoregions. Simple models for projecting road network growth will assist planning agencies and conservation organizations to guide protection efforts. We investigate growth of regular public roads in the State of Maine over a 17-year historical period, and then use the best-selected (AIC) logistic regression model to validate and then project spatial probability of future roads to the Northern Appalachian/Acadian ecoregion. Nearly 2000 km of new roads were constructed in settled landscapes in Maine 1986-2003, influencing 37,000 ha of adjacent habitats. The majority (93.5%) of the new roads performed local functions and were short (<1/3 km in length), characterized as residential roads typical of sprawl. The best-selected logit model [dwelling density (+), elevation (−), distance to urban area (−), distance to existing primary/secondary highway (−)] captured 84% of reserved new road points in Maine, and only 27% of random points at the >0.5 probability level. The projected model forecasts 0.5 million km of new residential public roads in the Northern Appalachian/Acadian ecoregion for the next two decades, suggesting that cumulative effects of residential road network expansion are a serious region-scale biodiversity threat.
Geophysical Research Letters, 2004
We have analyzed twentieth-century temperature data from 73 climate stations in New England and N... more We have analyzed twentieth-century temperature data from 73 climate stations in New England and New York. Linear regression gives a 100-year temperature change (ΔT100) for each station. All but two stations show an increase over this time, giving a regional area-weighted average ΔT100 of 1.11°C. Average ΔT100 values for each state are all positive, ranging from 0.86°C to 1.86°C. Spatial
Environmental History, 2002
Environmental History, 2000
... xii Acknowledgments College library; and Nancy Sherman, Vermont Public Service Department. ..... more ... xii Acknowledgments College library; and Nancy Sherman, Vermont Public Service Department. ... Portions of this book were read and edited by several people, to whom we are forever indebted: Jim Andrews, Ray Coish, Lucy Harding, Charles Johnson, Marc Lapin, Audi Lloyd ...