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• 491. [Article] Movement and space use by the green hermit (Phaethornis guy) in a fragmented landscape in Costa Rica

  Human activities have altered Earth’s ecosystems. Most biomes have experienced a 20-50% conversion to human use. Loss of habitat has obvious effects on the persistence of species. Fragmentation, however, ...

  Citation × Citation Citation Abstract Copy Title: Movement and space use by the green hermit (Phaethornis guy) in a fragmented landscape in Costa Rica Author: Volpe, Noelia L. Human activities have altered Earth’s ecosystems. Most biomes have experienced a 20-50% conversion to human use. Loss of habitat has obvious effects on the persistence of species. Fragmentation, however, may also negatively affect biodiversity for those species that exhibit behavioral responses to changes in habitat configuration. Such behavioral changes include movement, which is influenced by subdividing and isolating habitats through which animals prefer to travel. Ecosystem services that depend on the ability of animals to move through the landscape could be affected by changes in habitat configuration. Pollination is one such process because access of pollinators to flowers is often the key determinant of plant reproductive success. Yet, relatively little is known about how forest fragmentation may influence the flow of pollen carried by forest-dwelling pollinators, such as hummingbirds. I evaluate how changes in the distribution of pollinators produced by habitat fragmentation in southern Costa Rica affects a pollination web occupied by a generalist tropical pollinator, the green hermit hummingbird (Phaethornis guy). I used radio-telemetry to measure patterns of space use by green hermits living in forested areas with different levels of fragmentation. I first characterize patterns of space use by green hermits at three scales: point, path and home range. I found that green hermits have marked preference for locations in forested areas with high density of Heliconia plants and canopy cover; prefer paths close to streams that minimize crossing large stretches of non-forested matrix; and establish their home ranges in areas with high forest amount. In addition, home range area was negatively related to the amount of forest within it and positively related to fragmentation per se. Average resource density within the home range appeared to be unrelated to the area covered by the green hermits. My observations indicate that while the presence of green hermits in an area is mainly determined by the amount of forest available, the way they move through a landscape will be strongly affected by habitat configuration. In this context, pollen transfer by green hermits will be limited by the presence of open, non-forested areas owing to matrix avoidance. In landscapes with small discontinuous patches, the total area covered by an individual green hermit is likely to be small so I hypothesize that the genetic variability of pollen it transports may be diminished. I also assess the effectiveness of a tool commonly used to study the effect of habitat fragmentation on animal movement: translocation experiments. Such experiments are purported to have important advantages of being time efficient and standardizing across individuals the ‘motivation’ to move. Yet, we lack tests of whether movement behavior of translocated birds reflects natural behavior of unmanipulated birds. I compared the routine movement behavior of green hermits to that of experimentally translocated individuals. Behaviors documented during translocation experiments reflected those observed during routine movements. Both translocated and non-translocated birds showed similar levels of preference for mature tropical forest at the point level and avoided moving across non-forested matrix while selecting streams as movement corridors at the path level. Movement rates (distance covered per unit time) were generally higher during translocation experiments. However, the negative influence of forest cover on movement rates was proportionately similar in translocation and routine movement treatments. My results show that movement behavior of birds during translocation experiments is similar to natural movement behavior of birds. Therefore, translocation experiments may be reliable tools to address effects of landscape structure on animal movement. Title: Movement and space use by the green hermit (Phaethornis guy) in a fragmented landscape in Costa Rica Author: Volpe, Noelia L. Human activities have altered Earth’s ecosystems. Most biomes have experienced a 20-50% conversion to human use. Loss of habitat has obvious effects on the persistence of species. Fragmentation, however, may also negatively affect biodiversity for those species that exhibit behavioral responses to changes in habitat configuration. Such behavioral changes include movement, which is influenced by subdividing and isolating habitats through which animals prefer to travel. Ecosystem services that depend on the ability of animals to move through the landscape could be affected by changes in habitat configuration. Pollination is one such process because access of pollinators to flowers is often the key determinant of plant reproductive success. Yet, relatively little is known about how forest fragmentation may influence the flow of pollen carried by forest-dwelling pollinators, such as hummingbirds. I evaluate how changes in the distribution of pollinators produced by habitat fragmentation in southern Costa Rica affects a pollination web occupied by a generalist tropical pollinator, the green hermit hummingbird (Phaethornis guy). I used radio-telemetry to measure patterns of space use by green hermits living in forested areas with different levels of fragmentation. I first characterize patterns of space use by green hermits at three scales: point, path and home range. I found that green hermits have marked preference for locations in forested areas with high density of Heliconia plants and canopy cover; prefer paths close to streams that minimize crossing large stretches of non-forested matrix; and establish their home ranges in areas with high forest amount. In addition, home range area was negatively related to the amount of forest within it and positively related to fragmentation per se. Average resource density within the home range appeared to be unrelated to the area covered by the green hermits. My observations indicate that while the presence of green hermits in an area is mainly determined by the amount of forest available, the way they move through a landscape will be strongly affected by habitat configuration. In this context, pollen transfer by green hermits will be limited by the presence of open, non-forested areas owing to matrix avoidance. In landscapes with small discontinuous patches, the total area covered by an individual green hermit is likely to be small so I hypothesize that the genetic variability of pollen it transports may be diminished. I also assess the effectiveness of a tool commonly used to study the effect of habitat fragmentation on animal movement: translocation experiments. Such experiments are purported to have important advantages of being time efficient and standardizing across individuals the ‘motivation’ to move. Yet, we lack tests of whether movement behavior of translocated birds reflects natural behavior of unmanipulated birds. I compared the routine movement behavior of green hermits to that of experimentally translocated individuals. Behaviors documented during translocation experiments reflected those observed during routine movements. Both translocated and non-translocated birds showed similar levels of preference for mature tropical forest at the point level and avoided moving across non-forested matrix while selecting streams as movement corridors at the path level. Movement rates (distance covered per unit time) were generally higher during translocation experiments. However, the negative influence of forest cover on movement rates was proportionately similar in translocation and routine movement treatments. My results show that movement behavior of birds during translocation experiments is similar to natural movement behavior of birds. Therefore, translocation experiments may be reliable tools to address effects of landscape structure on animal movement. Close

• 492. [Article] Using a species-centered approach to examine patterns and drivers of avian species richness in the Rogue Basin, Oregon

  The combined effects of habitat loss, degradation, and fragmentation pose a serious threat to Earth's biodiversity, imperiling even relatively common species. 'Habitat' is necessarily a species-specific ...

  Citation × Citation Citation Abstract Copy Title: Using a species-centered approach to examine patterns and drivers of avian species richness in the Rogue Basin, Oregon Author: Halstead, Katherine E. The combined effects of habitat loss, degradation, and fragmentation pose a serious threat to Earth's biodiversity, imperiling even relatively common species. 'Habitat' is necessarily a species-specific concept, and investigations of bird diversity relationships and subsequent efforts to prioritize conservation areas, are challenged by the difficulty of estimating complex habitat gradients for multiple species across broad spatial scales. Technologies such as fine-resolution remote sensing combined with enhanced species distribution modeling techniques hold promise for more accurate assessments of multi-species habitat distributions. In this research, I focused on forest bird species which utilize and/or are highly associated with threatened Oregon white oak and California black oak (Quercus garrayana and Q. kelloggii) vegetation types in the Rogue Basin of southwest Oregon. I created individual species distribution models (SDMs) for 48 bird species as a function of fine-resolution (30 x 30 m) remotely sensed land cover and other environmental variables using boosted regression tree (BRT) models. I then 'stacked' SDMs for spatially explicit regional estimates of multi-species avian richness. In my first chapter, I examined the potential for site-level species richness to be influenced by local vegetation and environmental conditions (e.g. the "local vegetation heterogeneity hypothesis") or by landscape-level dispersal potential (e.g. the "regional species pool hypothesis"). I summarized 'stacked' SDMs for indices of 1) habitat amount at a local scale relevant bird territory use and 2) habitat amount at a broad scale relevant to forest bird dispersal, and ask whether local- or landscape-scale habitat amount is relatively more important to site-level bird species richness. I hypothesized that greater importance of either habitat amount metric would indicate greater influence of local or landscape drivers to local richness. I found evidence that for a large pool of bird species with diverse habitat associations, landscape-scale habitat amount may be relatively more important to local (i.e., territory level) richness of forest birds than is local habitat amount. In contrast, for more specialized (i.e., oak-associated) guilds, local-scale habitat may be considerably more important than amount of habitat within the surrounding landscape. My results suggest the importance of local- and landscape-scale processes in structuring bird communities, supporting both 'local vegetation heterogeneity' and 'regional species pool' hypotheses. In my second chapter, I examined the relationships between landownership, oak vegetation distribution, and bird diversity, with the objective of determining which of five primary landownership types contribute most strongly to bird species habitat in the Rogue Basin. I asked whether individual bird species distributions and estimated richness are 'additive' or 'redundant' among land ownership types, hypothesizing that differences among owners will be apparent and related to the amount of oak-dominant vegetation held by each owner regionally. I found that estimated local mean species richness of oak-associated birds in private non-industrial (PNI) ownerships is approximately double that of other Rogue Basin public and private ownerships examined. This result may be driven by disproportionate PNI ownership of limited oak cover types, and/or by hypothesized variation in management goals and activities among owners which influence local vegetation structure. Relatively greater importance of territory-scale habitat to local oak-associated species richness suggests management for these species should maximize site-level habitat amount and quality. The importance of private non-industrial owners to oak-associated avian richness validates current focus on engaging private landowners in bird-focused oak conservation and restoration. Overall, my research links efforts to conserve avian habitat with efforts to understand multi-scale drivers of bird diversity, using a novel methodology that embraces the complexity of species' habitat gradients. Title: Using a species-centered approach to examine patterns and drivers of avian species richness in the Rogue Basin, Oregon Author: Halstead, Katherine E. The combined effects of habitat loss, degradation, and fragmentation pose a serious threat to Earth's biodiversity, imperiling even relatively common species. 'Habitat' is necessarily a species-specific concept, and investigations of bird diversity relationships and subsequent efforts to prioritize conservation areas, are challenged by the difficulty of estimating complex habitat gradients for multiple species across broad spatial scales. Technologies such as fine-resolution remote sensing combined with enhanced species distribution modeling techniques hold promise for more accurate assessments of multi-species habitat distributions. In this research, I focused on forest bird species which utilize and/or are highly associated with threatened Oregon white oak and California black oak (Quercus garrayana and Q. kelloggii) vegetation types in the Rogue Basin of southwest Oregon. I created individual species distribution models (SDMs) for 48 bird species as a function of fine-resolution (30 x 30 m) remotely sensed land cover and other environmental variables using boosted regression tree (BRT) models. I then 'stacked' SDMs for spatially explicit regional estimates of multi-species avian richness. In my first chapter, I examined the potential for site-level species richness to be influenced by local vegetation and environmental conditions (e.g. the "local vegetation heterogeneity hypothesis") or by landscape-level dispersal potential (e.g. the "regional species pool hypothesis"). I summarized 'stacked' SDMs for indices of 1) habitat amount at a local scale relevant bird territory use and 2) habitat amount at a broad scale relevant to forest bird dispersal, and ask whether local- or landscape-scale habitat amount is relatively more important to site-level bird species richness. I hypothesized that greater importance of either habitat amount metric would indicate greater influence of local or landscape drivers to local richness. I found evidence that for a large pool of bird species with diverse habitat associations, landscape-scale habitat amount may be relatively more important to local (i.e., territory level) richness of forest birds than is local habitat amount. In contrast, for more specialized (i.e., oak-associated) guilds, local-scale habitat may be considerably more important than amount of habitat within the surrounding landscape. My results suggest the importance of local- and landscape-scale processes in structuring bird communities, supporting both 'local vegetation heterogeneity' and 'regional species pool' hypotheses. In my second chapter, I examined the relationships between landownership, oak vegetation distribution, and bird diversity, with the objective of determining which of five primary landownership types contribute most strongly to bird species habitat in the Rogue Basin. I asked whether individual bird species distributions and estimated richness are 'additive' or 'redundant' among land ownership types, hypothesizing that differences among owners will be apparent and related to the amount of oak-dominant vegetation held by each owner regionally. I found that estimated local mean species richness of oak-associated birds in private non-industrial (PNI) ownerships is approximately double that of other Rogue Basin public and private ownerships examined. This result may be driven by disproportionate PNI ownership of limited oak cover types, and/or by hypothesized variation in management goals and activities among owners which influence local vegetation structure. Relatively greater importance of territory-scale habitat to local oak-associated species richness suggests management for these species should maximize site-level habitat amount and quality. The importance of private non-industrial owners to oak-associated avian richness validates current focus on engaging private landowners in bird-focused oak conservation and restoration. Overall, my research links efforts to conserve avian habitat with efforts to understand multi-scale drivers of bird diversity, using a novel methodology that embraces the complexity of species' habitat gradients. Close

• 493. [Article] Lichen Functional Trait Variation Along an East-West Climatic Gradient in Oregon and Among Habitats in Katmai National Park, Alaska

  Functional traits of vascular plants have been an important component of ecological studies for a number of years; however, in more recent times vascular plant ecologists have begun to formalize a set ...

  Citation × Citation Citation Abstract Copy Title: Lichen Functional Trait Variation Along an East-West Climatic Gradient in Oregon and Among Habitats in Katmai National Park, Alaska Author: Spickerman, Kaleigh Functional traits of vascular plants have been an important component of ecological studies for a number of years; however, in more recent times vascular plant ecologists have begun to formalize a set of key traits and universal system of trait measurement. Many recent studies hypothesize global generality of trait patterns, which would allow for comparison among ecosystems and biomes and provide a foundation for general rules and theories, the so-called “Holy Grail” of ecology. However, the majority of these studies focus on functional trait patterns of vascular plants, with a minority examining the patterns of cryptograms such as lichens. Lichens are an important component of many ecosystems due to their contributions to biodiversity and their key ecosystem services, such as contributions to mineral and hydrological cycles and ecosystem food webs. Lichens are also of special interest because of their reliance on atmospheric deposition for nutrients and water, which makes them particularly sensitive to air pollution. Therefore, they are often used as bioindicators of air pollution, climate change, and general ecosystem health. This thesis examines the functional trait patterns of lichens in two contrasting regions with fundamentally different kinds of data. To better understand the patterns of lichen functional traits, we examined reproductive, morphological, and chemical trait variation along precipitation and temperature gradients in Oregon. Specifically, we measured traits of 102 macrolichen species collected from 166 USDA Forest Service program for Forest Inventory and Analysis (FIA) plots. These plots were located in a more-or-less continuous swath across Oregon between 43°W and 45°W. Plots were grouped into seven regions (the Oregon Coast, Coast Range, Willamette Valley, Western Cascades, High Cascades, Eastern Cascades, and Eastern Oregon). Using multivariate analysis techniques we found strong linear and nonlinear trait patterns along precipitation and temperature gradients, and were able to characterize the seven main regions of Oregon by the relative abundance of lichen traits. The literature on what lichen traits are most common in which habitats is sparse and anecdotal; understanding trait-habitat patterns could have management implications due to lichen importance as bioindicators and animal forage. Understanding how key traits are distributed among habitats could provide insight into potential air pollution impacts on certain habitats, animal movement among habitats, etc. To examine trait-habitat patterns, we measured the reproductive, morphological, and chemical traits of 429 lichen species collected haphazardly (without a formal sampling framework) from ten distinct habitats within Katmai National Park in southwest Alaska as part of a taxonomic inventory. Using multivariate analysis techniques we grouped habitats based on the expression of lichen traits and described the relative abundance of each trait in different habitats. The second goal of this study was to examine the potential usefulness of herbarium collections in ecological studies of this type. Herbarium specimens are a large potential resource that is generally unused in ecological studies due to concerns over potential bias and noise introduced by variation in collection methods. However, recent work has suggested that herbarium specimens may yield more useful results than previously thought and could be a valid resource for ecological studies. The data for our study were collected in a haphazard manner for a floristic inventory, similar to the collection methods used for many herbarium specimens. The patterns that we observed indicates that herbarium specimens may be a good resource for future research. Title: Lichen Functional Trait Variation Along an East-West Climatic Gradient in Oregon and Among Habitats in Katmai National Park, Alaska Author: Spickerman, Kaleigh Functional traits of vascular plants have been an important component of ecological studies for a number of years; however, in more recent times vascular plant ecologists have begun to formalize a set of key traits and universal system of trait measurement. Many recent studies hypothesize global generality of trait patterns, which would allow for comparison among ecosystems and biomes and provide a foundation for general rules and theories, the so-called “Holy Grail” of ecology. However, the majority of these studies focus on functional trait patterns of vascular plants, with a minority examining the patterns of cryptograms such as lichens. Lichens are an important component of many ecosystems due to their contributions to biodiversity and their key ecosystem services, such as contributions to mineral and hydrological cycles and ecosystem food webs. Lichens are also of special interest because of their reliance on atmospheric deposition for nutrients and water, which makes them particularly sensitive to air pollution. Therefore, they are often used as bioindicators of air pollution, climate change, and general ecosystem health. This thesis examines the functional trait patterns of lichens in two contrasting regions with fundamentally different kinds of data. To better understand the patterns of lichen functional traits, we examined reproductive, morphological, and chemical trait variation along precipitation and temperature gradients in Oregon. Specifically, we measured traits of 102 macrolichen species collected from 166 USDA Forest Service program for Forest Inventory and Analysis (FIA) plots. These plots were located in a more-or-less continuous swath across Oregon between 43°W and 45°W. Plots were grouped into seven regions (the Oregon Coast, Coast Range, Willamette Valley, Western Cascades, High Cascades, Eastern Cascades, and Eastern Oregon). Using multivariate analysis techniques we found strong linear and nonlinear trait patterns along precipitation and temperature gradients, and were able to characterize the seven main regions of Oregon by the relative abundance of lichen traits. The literature on what lichen traits are most common in which habitats is sparse and anecdotal; understanding trait-habitat patterns could have management implications due to lichen importance as bioindicators and animal forage. Understanding how key traits are distributed among habitats could provide insight into potential air pollution impacts on certain habitats, animal movement among habitats, etc. To examine trait-habitat patterns, we measured the reproductive, morphological, and chemical traits of 429 lichen species collected haphazardly (without a formal sampling framework) from ten distinct habitats within Katmai National Park in southwest Alaska as part of a taxonomic inventory. Using multivariate analysis techniques we grouped habitats based on the expression of lichen traits and described the relative abundance of each trait in different habitats. The second goal of this study was to examine the potential usefulness of herbarium collections in ecological studies of this type. Herbarium specimens are a large potential resource that is generally unused in ecological studies due to concerns over potential bias and noise introduced by variation in collection methods. However, recent work has suggested that herbarium specimens may yield more useful results than previously thought and could be a valid resource for ecological studies. The data for our study were collected in a haphazard manner for a floristic inventory, similar to the collection methods used for many herbarium specimens. The patterns that we observed indicates that herbarium specimens may be a good resource for future research. Close

• 494. [Article] Leveraging Multi-Sensor Time Series Datasets to Map Short- and Long-Term Forest Disturbances and Drivers of Change in the Colombian Andes

  The spatial distribution of forest disturbance is commonly calculated using a satellite imagery-driven bi- or tri-temporal change analysis. Working in Colombia’s Cordillera de los Picachos National Natural ...

  Citation × Citation Citation Abstract Copy Title: Leveraging Multi-Sensor Time Series Datasets to Map Short- and Long-Term Forest Disturbances and Drivers of Change in the Colombian Andes Author: Murillo Sandoval, Paulo Jose The spatial distribution of forest disturbance is commonly calculated using a satellite imagery-driven bi- or tri-temporal change analysis. Working in Colombia’s Cordillera de los Picachos National Natural Park – a region of consistent cloud cover and dramatic topographic relief – a change assessment with such infrequent observations cannot capture long-term trends of vegetative decline (browning) or improvement (greening) nor the drivers associated with these changes. In recognition of the importance of spatio-temporally explicit information for assessing the effects of socio-environmental change and conservation strategy implementation, I developed a rigorous assessment of vegetation change using MODIS and Landsat time-series data and the Breaks For Additive Season and Trend (BFAST) algorithm to identify the timing, trends, and locations of change as well the associated drivers. First, I measured long-term vegetation trends from 2001-2015 using a Moderate Resolution Imaging Spectroradiometer (MODIS)-based 250m resolution Multi-Angle Implementation of Atmospheric Correction (MAIAC) time-series, and mapped short-term disturbances using all available Landsat images (149 dates from Landsat 5, 7, and 8). BFAST trends based on MAIAC data indicate a net greening in 6% of the park, with a net browning trend of 2.5% in the 10km-wide region surrounding the park. I also identified a 12,500 ha area within Picachos (4% of the park’s total area) that experienced a consecutive vegetative decline or browning during every year of study, a result corroborated with a BFAST Monitor assessment using finer 30m resolution Landsat data. With Landsat, I recorded 12,642 ha (±1440) of disturbed forest within the park at high spatial and temporal accuracy. Spatially, Landsat results had user’s and producer’s accuracies of 0.95±0.02 and 0.83±0.18, respectively. Temporally, a TimeSync-supported temporal validation assessment showed that 75% of Landsat-detected dates of disturbance events were accurate within ± 6 months. With disturbances identified, I characterized disturbances within Picachos’ southeastern foothills and associated drivers using a set of metrics related to the spectral, pattern and trend properties of disturbance patches derived from Landsat time-series data (1996-2015). A training dataset was initially developed to identify drivers of disturbances using Corine Land Cover maps and high-resolution imagery. A Random Forests classifier was used to attribute disturbances to specific drivers of forest cover change: conversion to pasture, conversion to subsistence agriculture, and non-stand replacing disturbance (i.e., thinning). Attribution of changes had high accuracy at patch and area levels with 1-5% commission and 2-14% omission errors, respectively, for regions that were converted to pasture or experienced thinning. Lower agreement was found for agricultural conversion with 43% omission and 9% commission errors. I found that conversion to pasture is the main cause of forest cover loss within Picachos at 9901 ha (±72) corresponding to 14.7% of Picachos’ foothills, and that subtle forest alteration contributed to 1327 ha (±92) of forest degradation. Recognizing the diversity of pressures facing conservation strategy implementation in the region, these results have direct relevance for anticipating future land use pressures within Colombia, as well as across similar regions in the Andes-Amazon transition area. Indeed, since these results reveal the possibility to uncover historical disturbances related to human-incursion in protected landscapes, the methods are well suited to enhancing landscape planning particularly where biodiversity richness is quickly diminishing due to anthropogenic presence. Title: Leveraging Multi-Sensor Time Series Datasets to Map Short- and Long-Term Forest Disturbances and Drivers of Change in the Colombian Andes Author: Murillo Sandoval, Paulo Jose The spatial distribution of forest disturbance is commonly calculated using a satellite imagery-driven bi- or tri-temporal change analysis. Working in Colombia’s Cordillera de los Picachos National Natural Park – a region of consistent cloud cover and dramatic topographic relief – a change assessment with such infrequent observations cannot capture long-term trends of vegetative decline (browning) or improvement (greening) nor the drivers associated with these changes. In recognition of the importance of spatio-temporally explicit information for assessing the effects of socio-environmental change and conservation strategy implementation, I developed a rigorous assessment of vegetation change using MODIS and Landsat time-series data and the Breaks For Additive Season and Trend (BFAST) algorithm to identify the timing, trends, and locations of change as well the associated drivers. First, I measured long-term vegetation trends from 2001-2015 using a Moderate Resolution Imaging Spectroradiometer (MODIS)-based 250m resolution Multi-Angle Implementation of Atmospheric Correction (MAIAC) time-series, and mapped short-term disturbances using all available Landsat images (149 dates from Landsat 5, 7, and 8). BFAST trends based on MAIAC data indicate a net greening in 6% of the park, with a net browning trend of 2.5% in the 10km-wide region surrounding the park. I also identified a 12,500 ha area within Picachos (4% of the park’s total area) that experienced a consecutive vegetative decline or browning during every year of study, a result corroborated with a BFAST Monitor assessment using finer 30m resolution Landsat data. With Landsat, I recorded 12,642 ha (±1440) of disturbed forest within the park at high spatial and temporal accuracy. Spatially, Landsat results had user’s and producer’s accuracies of 0.95±0.02 and 0.83±0.18, respectively. Temporally, a TimeSync-supported temporal validation assessment showed that 75% of Landsat-detected dates of disturbance events were accurate within ± 6 months. With disturbances identified, I characterized disturbances within Picachos’ southeastern foothills and associated drivers using a set of metrics related to the spectral, pattern and trend properties of disturbance patches derived from Landsat time-series data (1996-2015). A training dataset was initially developed to identify drivers of disturbances using Corine Land Cover maps and high-resolution imagery. A Random Forests classifier was used to attribute disturbances to specific drivers of forest cover change: conversion to pasture, conversion to subsistence agriculture, and non-stand replacing disturbance (i.e., thinning). Attribution of changes had high accuracy at patch and area levels with 1-5% commission and 2-14% omission errors, respectively, for regions that were converted to pasture or experienced thinning. Lower agreement was found for agricultural conversion with 43% omission and 9% commission errors. I found that conversion to pasture is the main cause of forest cover loss within Picachos at 9901 ha (±72) corresponding to 14.7% of Picachos’ foothills, and that subtle forest alteration contributed to 1327 ha (±92) of forest degradation. Recognizing the diversity of pressures facing conservation strategy implementation in the region, these results have direct relevance for anticipating future land use pressures within Colombia, as well as across similar regions in the Andes-Amazon transition area. Indeed, since these results reveal the possibility to uncover historical disturbances related to human-incursion in protected landscapes, the methods are well suited to enhancing landscape planning particularly where biodiversity richness is quickly diminishing due to anthropogenic presence. Close

• 495. [Article] Historical disturbance regimes as a reference for forest policy

  Using the historical range of forest conditions as a reference for managing landscapes has been proposed as a "coarse-filter" approach to biodiversity conservation. By emulating historical disturbance ...

  Citation × Citation Citation Abstract Copy Title: Historical disturbance regimes as a reference for forest policy Author: Thompson, Jonathan R. Using the historical range of forest conditions as a reference for managing landscapes has been proposed as a "coarse-filter" approach to biodiversity conservation. By emulating historical disturbance processes, it is thought that forest management can produce forest composition and structure similar to the conditions that once supported the native biota. Although several examples of disturbance-based management exist, only recently has this concept been incorporated into policy. This thesis explored hypotheses related to disturbance-based forest policy through a literature review, policy analyses, and simulation experiments. The primary objective of chapter 2 was to examine several examples disturbance-based forest management and evaluate their potential to transition into policy within North America. The review highlighted two Canadian provinces British Columbia and Ontario--that have codified disturbance-based management but used distinct methodologies. Nearly all of the forests in these provinces are government owned, which assisted policy development. In addition, both policy-structures focused on emulating stand-replacing fires that are characteristic in boreal forests; this minimized the costs and the degree of departure from conventional forest management. In much of the U.S., land tenure is complex and disturbance regimes vary widely; this presents difficult challenges for disturbance-based policy development. In the third chapter, disturbance-based policies were developed that attempted to address these challenges. Using datasets from the Coastal Landscape Analysis and Modeling Study (CLAMS) and the Landscape Management and Policy Simulation model (LAMPS), the economic costs and ecological benefits of several policy structures were explored. The policies included two variants of the current policy structure and three policies reflecting various aspects of the natural disturbance regime. The study area was the 3-million hectare Oregon Coast Range. Four owner groups were recognized--forest industry, nonindustrial private, state, and federal. The management intentions of each group guided the application of policies. Disturbance-based policies were primarily addressed to clearcutting on private lands because it constituted the preponderance of harvesting in the region. Information on the Coast Range's historical fire regime was used as a reference to develop disturbance-based policies. Fire severity was emulated with green-tree retention standards; fire frequency was emulated with annual harvestable area restrictions; and fire extent was emulated with harvest-unit size regulations. LAMPS projected landscape conditions, forest dynamics, management activities (clearcutting, thinning), and harvest volumes over the next century. Simulated disturbance-based policies produced age-class distributions more similar to the historical range than those created by the current policy structure. The proportions of early seral and young forest were within the historical range within 100 yrs; within this timeframe, older forests moved closer to but were still below historical conditions. In contrast, patch size distributions were less similar to historical conditions. This was because, even after a ten-fold increase in the average harvest size, the clearcut size limit remained well below the average historical fire size. Also, this was due to the scale of the analysis, which treated multiple proximate harvest-units as individual disturbance events. Therefore, regions with a high density of clearcuts, which were ubiquitous in the current policy scenarios, more closely resembled the large historical fire size. In the near term, annual revenue produced by the disturbance-based policies was estimated to be 20 to 60 percent lower than the current policy. However, relative costs were reduced significantly through time. This reflected the degree of departure between the modem and historical disturbance regimes. This simulation experiment suggested that policies attempting to reproduce historical conditions in the Coast Range would require federal forests to provide large patches of old forest that were conmon in the historical landscape. Employing public lands for this purpose would dampen costs to private landowners who would continue harvesting and provide young and early seral forest structure, which were also historically abundant. In addition, this experiment illustrated the difficultly of meeting regional-scale conservation goals across multiple private landowners and suggested that distributing costs and benefits equitably across large landscapes could be a significant challenge. Title: Historical disturbance regimes as a reference for forest policy Author: Thompson, Jonathan R. Using the historical range of forest conditions as a reference for managing landscapes has been proposed as a "coarse-filter" approach to biodiversity conservation. By emulating historical disturbance processes, it is thought that forest management can produce forest composition and structure similar to the conditions that once supported the native biota. Although several examples of disturbance-based management exist, only recently has this concept been incorporated into policy. This thesis explored hypotheses related to disturbance-based forest policy through a literature review, policy analyses, and simulation experiments. The primary objective of chapter 2 was to examine several examples disturbance-based forest management and evaluate their potential to transition into policy within North America. The review highlighted two Canadian provinces British Columbia and Ontario--that have codified disturbance-based management but used distinct methodologies. Nearly all of the forests in these provinces are government owned, which assisted policy development. In addition, both policy-structures focused on emulating stand-replacing fires that are characteristic in boreal forests; this minimized the costs and the degree of departure from conventional forest management. In much of the U.S., land tenure is complex and disturbance regimes vary widely; this presents difficult challenges for disturbance-based policy development. In the third chapter, disturbance-based policies were developed that attempted to address these challenges. Using datasets from the Coastal Landscape Analysis and Modeling Study (CLAMS) and the Landscape Management and Policy Simulation model (LAMPS), the economic costs and ecological benefits of several policy structures were explored. The policies included two variants of the current policy structure and three policies reflecting various aspects of the natural disturbance regime. The study area was the 3-million hectare Oregon Coast Range. Four owner groups were recognized--forest industry, nonindustrial private, state, and federal. The management intentions of each group guided the application of policies. Disturbance-based policies were primarily addressed to clearcutting on private lands because it constituted the preponderance of harvesting in the region. Information on the Coast Range's historical fire regime was used as a reference to develop disturbance-based policies. Fire severity was emulated with green-tree retention standards; fire frequency was emulated with annual harvestable area restrictions; and fire extent was emulated with harvest-unit size regulations. LAMPS projected landscape conditions, forest dynamics, management activities (clearcutting, thinning), and harvest volumes over the next century. Simulated disturbance-based policies produced age-class distributions more similar to the historical range than those created by the current policy structure. The proportions of early seral and young forest were within the historical range within 100 yrs; within this timeframe, older forests moved closer to but were still below historical conditions. In contrast, patch size distributions were less similar to historical conditions. This was because, even after a ten-fold increase in the average harvest size, the clearcut size limit remained well below the average historical fire size. Also, this was due to the scale of the analysis, which treated multiple proximate harvest-units as individual disturbance events. Therefore, regions with a high density of clearcuts, which were ubiquitous in the current policy scenarios, more closely resembled the large historical fire size. In the near term, annual revenue produced by the disturbance-based policies was estimated to be 20 to 60 percent lower than the current policy. However, relative costs were reduced significantly through time. This reflected the degree of departure between the modem and historical disturbance regimes. This simulation experiment suggested that policies attempting to reproduce historical conditions in the Coast Range would require federal forests to provide large patches of old forest that were conmon in the historical landscape. Employing public lands for this purpose would dampen costs to private landowners who would continue harvesting and provide young and early seral forest structure, which were also historically abundant. In addition, this experiment illustrated the difficultly of meeting regional-scale conservation goals across multiple private landowners and suggested that distributing costs and benefits equitably across large landscapes could be a significant challenge. Close

• 496. [Article] An evaluation of the likelihood of successful implementation of the long term coral reef monitoring program on the Commonwealth of the Northern Mariana Islands

  Coral reef ecosystems are the oceanic equivalent of tropical rainforests, in terms of biodiversity. The estimated 1,037,000 square kilometers worldwide of reef provide habitat for over one million species ...

  Citation × Citation Citation Abstract Copy Title: An evaluation of the likelihood of successful implementation of the long term coral reef monitoring program on the Commonwealth of the Northern Mariana Islands Author: Kylstra, Pam Coral reef ecosystems are the oceanic equivalent of tropical rainforests, in terms of biodiversity. The estimated 1,037,000 square kilometers worldwide of reef provide habitat for over one million species of plants and animals (Hinrichsen, 1997). Coral reefs are important to the economy of coastal nations because of the fisheries and tourism industries they support. Reef ecosystems provide a host of important natural services such as storm buffering, a protein source for islanders, breeding and nursery grounds for marine organisms, water filtration and a source of biomedically important products. Coral reef areas also have aesthetic and intrinsic value that is reason enough to protect them. Coral reefs are also among the most endangered ecosystems on Earth. Naturally occurring disturbances are compounded by the impacts of anthropogenic disturbance. Factors that threaten the health of coral reef ecosystems on a global scale include global warming, the continuing increase in coastal populations and associated impacts such as nutrient pollution, sedimentation and runoff, coral mining, ship groundings, overfishing, and recreational overuse. Globally, coastal areas accommodate about 60% of Earth's human population. A significant portion of the population lies within tropical regions. This population pressure subjects coral reef environments to effects of increased competition for coastal resources, increased coastal pollution and problems related to coastal construction. The synergistic effect of stressors has been the irreversible degradation worldwide of 10% of reefs and another 60% in critical condition leaving, only 30% as stable (Wilkinson, 1993). The coral reefs of the Commonwealth of the Northern Mariana Islands (CNMI) are a good example of how the combination of increasing human population and the associated environmental pressure has resulted in degradation of the reef ecosystem. The CNMI has undergone significant change in economic and population growth within the past decade. To accommodate the rapid and continuing development of the tourism industry, numerous golf courses and resort hotels have been constructed on Saipan. The population of Saipan has increased over 30% in the last ten years. Currently, the local/resident population is 60,000 while the visitor population is 750,000 per year. This rapid growth has had serious ecological consequences. Coral roads have been converted to four lane highways and infrastructure such as septic tank systems has not been improved to meet higher demand. More and more development projects have been proposed without adequate consideration of environmental impacts. Conflicts over the use and conservation of marine and watershed resources continue to arise. The continuing decline of reef systems globally and in specific areas like the CNMI, highlights the need for effective methods of assessing change in nearshore ecosystems. This paper explores the ways that coral reef monitoring can provide information about reef health that serves to affect positive changes in management strategies for marine systems. Using a criteria drawn from case study comparisons of ongoing, well established coral monitoring programs and evaluation framework proposed by policy analysts Using criteria drawn from case, the Long Term Marine Monitoring Program (LTMMP) on Saipan, CNMI is evaluated. The evaluation provides insight about coral monitoring plan components that are essential to the effectiveness of coral reef monitoring programs. This report is an outgrowth of an internship the author performed with the CNMI Division of Environmental Quality on the island of Saipan from June to October of 1997. The University of Oregon Micronesia and South Pacific Program and the government of the Commonwealth of the Northern Mariana Islands (CMNI) sponsored the internship project. The objectives of the internship were to assist in field data collection and continuing development of the ongoing Long Term Marine Monitoring Plan (LTMMP) Assist and instruct Marine Monitoring Team (MMT) members in basic computer skills, understanding of data applicability, management, interpretation and analysis, basic biology and resource management techniques as it relates to marine monitoring work Facilitate inter-governmental agency coordination of marine monitoring activities Assess likelihood of success and explore challenges facing Saipan in implementation of the monitoring program This report first describes functions and services provided by coral reefs and an introduction to the stresses and disturbances that compromise the health of reef systems globally. Using examples from case studies of established marine monitoring programs, this report considers how effective monitoring can reveal changes in the reef system over time, enabling conservation measures to be taken. It then turns to the island of Saipan and briefly describes the environmental and socio-economic framework within which the coral reef related provisions of the CNMI coastal management program are considered. This background information is used to evaluate the Long Term Marine Monitoring Plan currently in place on the CNMI. This evaluation provides insight into the challenges to implementation of coral reef monitoring plans and recommendations for improvements in the LTMMP on Saipan. Title: An evaluation of the likelihood of successful implementation of the long term coral reef monitoring program on the Commonwealth of the Northern Mariana Islands Author: Kylstra, Pam Coral reef ecosystems are the oceanic equivalent of tropical rainforests, in terms of biodiversity. The estimated 1,037,000 square kilometers worldwide of reef provide habitat for over one million species of plants and animals (Hinrichsen, 1997). Coral reefs are important to the economy of coastal nations because of the fisheries and tourism industries they support. Reef ecosystems provide a host of important natural services such as storm buffering, a protein source for islanders, breeding and nursery grounds for marine organisms, water filtration and a source of biomedically important products. Coral reef areas also have aesthetic and intrinsic value that is reason enough to protect them. Coral reefs are also among the most endangered ecosystems on Earth. Naturally occurring disturbances are compounded by the impacts of anthropogenic disturbance. Factors that threaten the health of coral reef ecosystems on a global scale include global warming, the continuing increase in coastal populations and associated impacts such as nutrient pollution, sedimentation and runoff, coral mining, ship groundings, overfishing, and recreational overuse. Globally, coastal areas accommodate about 60% of Earth's human population. A significant portion of the population lies within tropical regions. This population pressure subjects coral reef environments to effects of increased competition for coastal resources, increased coastal pollution and problems related to coastal construction. The synergistic effect of stressors has been the irreversible degradation worldwide of 10% of reefs and another 60% in critical condition leaving, only 30% as stable (Wilkinson, 1993). The coral reefs of the Commonwealth of the Northern Mariana Islands (CNMI) are a good example of how the combination of increasing human population and the associated environmental pressure has resulted in degradation of the reef ecosystem. The CNMI has undergone significant change in economic and population growth within the past decade. To accommodate the rapid and continuing development of the tourism industry, numerous golf courses and resort hotels have been constructed on Saipan. The population of Saipan has increased over 30% in the last ten years. Currently, the local/resident population is 60,000 while the visitor population is 750,000 per year. This rapid growth has had serious ecological consequences. Coral roads have been converted to four lane highways and infrastructure such as septic tank systems has not been improved to meet higher demand. More and more development projects have been proposed without adequate consideration of environmental impacts. Conflicts over the use and conservation of marine and watershed resources continue to arise. The continuing decline of reef systems globally and in specific areas like the CNMI, highlights the need for effective methods of assessing change in nearshore ecosystems. This paper explores the ways that coral reef monitoring can provide information about reef health that serves to affect positive changes in management strategies for marine systems. Using a criteria drawn from case study comparisons of ongoing, well established coral monitoring programs and evaluation framework proposed by policy analysts Using criteria drawn from case, the Long Term Marine Monitoring Program (LTMMP) on Saipan, CNMI is evaluated. The evaluation provides insight about coral monitoring plan components that are essential to the effectiveness of coral reef monitoring programs. This report is an outgrowth of an internship the author performed with the CNMI Division of Environmental Quality on the island of Saipan from June to October of 1997. The University of Oregon Micronesia and South Pacific Program and the government of the Commonwealth of the Northern Mariana Islands (CMNI) sponsored the internship project. The objectives of the internship were to assist in field data collection and continuing development of the ongoing Long Term Marine Monitoring Plan (LTMMP) Assist and instruct Marine Monitoring Team (MMT) members in basic computer skills, understanding of data applicability, management, interpretation and analysis, basic biology and resource management techniques as it relates to marine monitoring work Facilitate inter-governmental agency coordination of marine monitoring activities Assess likelihood of success and explore challenges facing Saipan in implementation of the monitoring program This report first describes functions and services provided by coral reefs and an introduction to the stresses and disturbances that compromise the health of reef systems globally. Using examples from case studies of established marine monitoring programs, this report considers how effective monitoring can reveal changes in the reef system over time, enabling conservation measures to be taken. It then turns to the island of Saipan and briefly describes the environmental and socio-economic framework within which the coral reef related provisions of the CNMI coastal management program are considered. This background information is used to evaluate the Long Term Marine Monitoring Plan currently in place on the CNMI. This evaluation provides insight into the challenges to implementation of coral reef monitoring plans and recommendations for improvements in the LTMMP on Saipan. Close

• 497. [Article] The importance of egg size for the diversity of salmonids

  Understanding the origin and nature of intra specific biodiversity enables us to better conserve and manage animal populations. Biological diversity is seen at different scales and for different traits ...

  Citation × Citation Citation Abstract Copy Title: The importance of egg size for the diversity of salmonids Author: Leblanc, Camille A. Understanding the origin and nature of intra specific biodiversity enables us to better conserve and manage animal populations. Biological diversity is seen at different scales and for different traits such as behavior, morphology, physiology, and life history. Behavior is especially important since behavioral changes are believed to precede changes in morphology or physiology among fishes. Salmonids display great diversity in terms of behavior, life histories and morphology within and among populations. Thus, differentiation among populations and morphs has been related to the evolution of new species. Various genetic, environmental and ecological factors have been shown to be important for segregation of morphs, including competition for food or other resources, phenotypic plasticity and sexual selection. Recently, it has been suggested that the importance of epigenetic and maternal effects for intra specific diversity have been underestimated. I studied the short- and long-term effects of egg size on development, behavior, body growth and physiology in Arctic charr Salvelinus alpinus and steelhead trout Oncorhynchus mykiss. I also examined how domestication can affect egg size. Egg size was smaller in domesticated fish populations after accounting for female body size and age. Egg size was negatively correlated with embryonic development before hatching, i.e. embryos in small eggs developed more rapidly. At emergence, egg size was positively correlated with length and weight of first feeding progeny. Juveniles coming from larger eggs tended to feed more at the surface whereas juveniles coming from smaller eggs fed more on the bottom. These relationships and effects of egg size on embryos and first feeding fish were observed in both species in laboratory conditions. In Arctic charr there was a higher energy content per egg in larger eggs in both aquaculture and wild populations, and the total energy content per egg varied among populations. Behavior of Arctic charr at first feeding was affected by egg size, social environment and their interaction. At 300 days post fertilization, fish coming from different egg sizes differed in morphology and behavior: larger fish coming from larger eggs fed more at the surface than smaller fish coming from smaller eggs. Independently of their genetic origin large and small juveniles, coming respectively from large and small eggs, differed in body shape. This was most clearly seen in head and body morphology, e.g. larger fish were overall slimmer than smaller fish. The influence of egg size on behavior and morphology of Arctic charr varied with female parentage, indicating strong maternal x genetic interactions. In steelhead trout, both origin of fish and egg size were related with body growth of yearling fish reared under laboratory conditions: hatchery juveniles coming from small eggs were larger than wild juveniles coming from small eggs. Both were in turn larger than hatchery and wild juveniles coming from large eggs. Hatchery progeny showed lower osmo-regulatory status compared to wild progeny but nevertheless preferentially chose salt water. This study presents novel findings that demonstrate that variability in egg size is an important source of phenotypic variation in fishes. My results support the hypothesis that females experiencing relatively high growth rate as juveniles produce a large number of small eggs as adults and that such a reduction in egg size happens rapidly, i.e. in only one generation in domestication. I discuss the implications of egg size for evolution of fishes and, especially how diversity created by egg size can influence diversification and speciation of fishes. Title: The importance of egg size for the diversity of salmonids Author: Leblanc, Camille A. Understanding the origin and nature of intra specific biodiversity enables us to better conserve and manage animal populations. Biological diversity is seen at different scales and for different traits such as behavior, morphology, physiology, and life history. Behavior is especially important since behavioral changes are believed to precede changes in morphology or physiology among fishes. Salmonids display great diversity in terms of behavior, life histories and morphology within and among populations. Thus, differentiation among populations and morphs has been related to the evolution of new species. Various genetic, environmental and ecological factors have been shown to be important for segregation of morphs, including competition for food or other resources, phenotypic plasticity and sexual selection. Recently, it has been suggested that the importance of epigenetic and maternal effects for intra specific diversity have been underestimated. I studied the short- and long-term effects of egg size on development, behavior, body growth and physiology in Arctic charr Salvelinus alpinus and steelhead trout Oncorhynchus mykiss. I also examined how domestication can affect egg size. Egg size was smaller in domesticated fish populations after accounting for female body size and age. Egg size was negatively correlated with embryonic development before hatching, i.e. embryos in small eggs developed more rapidly. At emergence, egg size was positively correlated with length and weight of first feeding progeny. Juveniles coming from larger eggs tended to feed more at the surface whereas juveniles coming from smaller eggs fed more on the bottom. These relationships and effects of egg size on embryos and first feeding fish were observed in both species in laboratory conditions. In Arctic charr there was a higher energy content per egg in larger eggs in both aquaculture and wild populations, and the total energy content per egg varied among populations. Behavior of Arctic charr at first feeding was affected by egg size, social environment and their interaction. At 300 days post fertilization, fish coming from different egg sizes differed in morphology and behavior: larger fish coming from larger eggs fed more at the surface than smaller fish coming from smaller eggs. Independently of their genetic origin large and small juveniles, coming respectively from large and small eggs, differed in body shape. This was most clearly seen in head and body morphology, e.g. larger fish were overall slimmer than smaller fish. The influence of egg size on behavior and morphology of Arctic charr varied with female parentage, indicating strong maternal x genetic interactions. In steelhead trout, both origin of fish and egg size were related with body growth of yearling fish reared under laboratory conditions: hatchery juveniles coming from small eggs were larger than wild juveniles coming from small eggs. Both were in turn larger than hatchery and wild juveniles coming from large eggs. Hatchery progeny showed lower osmo-regulatory status compared to wild progeny but nevertheless preferentially chose salt water. This study presents novel findings that demonstrate that variability in egg size is an important source of phenotypic variation in fishes. My results support the hypothesis that females experiencing relatively high growth rate as juveniles produce a large number of small eggs as adults and that such a reduction in egg size happens rapidly, i.e. in only one generation in domestication. I discuss the implications of egg size for evolution of fishes and, especially how diversity created by egg size can influence diversification and speciation of fishes. Close

• 498. [Article] Lichen communities and caribou habitat in Denali National Park and Preserve, Alaska, USA

  Lichens play many important roles in subarctic terrestrial ecosystems by fixing nitrogen, colonizing rock and gravel, stabilizing otherwise bare soil, adding significantly to vegetation biodiversity and ...

  Citation × Citation Citation Abstract Copy Title: Lichen communities and caribou habitat in Denali National Park and Preserve, Alaska, USA Author: Nelson, Peter, 1970- Lichens play many important roles in subarctic terrestrial ecosystems by fixing nitrogen, colonizing rock and gravel, stabilizing otherwise bare soil, adding significantly to vegetation biodiversity and serving as the primary food for caribou in the winter. In these chapters, I analyzed lichen community and ecological trait structure along environmental gradients, map lichens using some of their unique spectral properties to generate lichen maps and study caribou habitat selection patterns in relation to lichens and other habitat variables. Morphological and life history traits of lichens influence their ecological roles through physiological limitations imposed by their form and photobionts, the algal or cyanobacterial partner. In chapter 2, I analyzed the lichen traits in relationship to environmental gradients, other forms of vegetation and time since fire in Denali National Park and Preserve, Alaska. Lichens with different photobionts reached different maxima along environmental gradients, these corresponding to variable water availability or specific biotic factors thought to favor that photobiont. Green algal lichens were most abundant in the alpine whereas cyanolichens peaked where shrub cover increased. Tripartite lichens were most abundant in middle elevation, mossy areas. Lichen growthforms peaked along desiccation and water absorption gradients. Lichens with small vegetative propagules were most abundant in lowland forests. Recent fire favored simple, Cladonia-form lichens with soredia that grow on wood whereas erect branched fruticose lichens, the "reindeer lichens", had only partially recovered 20-100 years after fire. These results imply interacting forces of water regulation, dispersal and optimum conditions for photosynthesis drive lichen trait frequency and abundance. The fungal partner within the lichen symbiosis produces many unique compounds that are often brightly colored. Other studies have attempted to map lichens using their distinctive spectral properties but no study has yet to target specific lichen compounds in order to better model lichen cover. In chapter 3, I focused on one yellow lichen compound, usnic acid, as the target for modeling lichen cover using Landsat 7 ETM+ satellite data. Usnic lichen cover had non-linear relationships with the three best predictors; elevation, blue and near-infrared bandpasses. Using these three predictors, I generated an usnic lichen map for Denali, which I use in chapter 4 for analyzing caribou habitat selection. I also modeled and mapped other vegetation groups corresponding to caribou diet items used later. My results show that some lichens may be directly mapped from space by targeting this specific compound produced by the fungus. Caribou depend on lichens for up to 66% of their winter diet but other factors, such as snow, affect their access to the lichens. In chapter 4, I analyzed caribou habitat selection over 20 years in Denali using vegetation maps from chapter 3, climate data and other environmental variables. Over the two-decade period, caribou selected middle elevation, open areas with high graminoid cover and earlier snow-free dates. As each winter progressed, caribou aggregated where there was higher lichen cover and earlier snow-melt. Caribou selected habitat differently between years, which I collapsed into three different habitat/year groups: (1) years where most animals were in low elevation, flat terrain where there was low lichen and conifer cover but high graminoid and shrub cover with variable snow; (2) years caribou went to middle elevations with deeper snow and rugged terrain and moderate graminoid and lichen cover; and (3) years where caribou were dispersed west in low elevation woodlands with high lichen cover. My results show interacting factors determine caribou habitat selection at multiple spatial scales, specifically the importance of open, tussock tundra and long-term trends in snow melt at long time scales and lichen and snow-melt at shorter time scales. This research improves our understanding of the regional distribution and abundance of lichens in relation to higher plants, fire, and caribou. Title: Lichen communities and caribou habitat in Denali National Park and Preserve, Alaska, USA Author: Nelson, Peter, 1970- Lichens play many important roles in subarctic terrestrial ecosystems by fixing nitrogen, colonizing rock and gravel, stabilizing otherwise bare soil, adding significantly to vegetation biodiversity and serving as the primary food for caribou in the winter. In these chapters, I analyzed lichen community and ecological trait structure along environmental gradients, map lichens using some of their unique spectral properties to generate lichen maps and study caribou habitat selection patterns in relation to lichens and other habitat variables. Morphological and life history traits of lichens influence their ecological roles through physiological limitations imposed by their form and photobionts, the algal or cyanobacterial partner. In chapter 2, I analyzed the lichen traits in relationship to environmental gradients, other forms of vegetation and time since fire in Denali National Park and Preserve, Alaska. Lichens with different photobionts reached different maxima along environmental gradients, these corresponding to variable water availability or specific biotic factors thought to favor that photobiont. Green algal lichens were most abundant in the alpine whereas cyanolichens peaked where shrub cover increased. Tripartite lichens were most abundant in middle elevation, mossy areas. Lichen growthforms peaked along desiccation and water absorption gradients. Lichens with small vegetative propagules were most abundant in lowland forests. Recent fire favored simple, Cladonia-form lichens with soredia that grow on wood whereas erect branched fruticose lichens, the "reindeer lichens", had only partially recovered 20-100 years after fire. These results imply interacting forces of water regulation, dispersal and optimum conditions for photosynthesis drive lichen trait frequency and abundance. The fungal partner within the lichen symbiosis produces many unique compounds that are often brightly colored. Other studies have attempted to map lichens using their distinctive spectral properties but no study has yet to target specific lichen compounds in order to better model lichen cover. In chapter 3, I focused on one yellow lichen compound, usnic acid, as the target for modeling lichen cover using Landsat 7 ETM+ satellite data. Usnic lichen cover had non-linear relationships with the three best predictors; elevation, blue and near-infrared bandpasses. Using these three predictors, I generated an usnic lichen map for Denali, which I use in chapter 4 for analyzing caribou habitat selection. I also modeled and mapped other vegetation groups corresponding to caribou diet items used later. My results show that some lichens may be directly mapped from space by targeting this specific compound produced by the fungus. Caribou depend on lichens for up to 66% of their winter diet but other factors, such as snow, affect their access to the lichens. In chapter 4, I analyzed caribou habitat selection over 20 years in Denali using vegetation maps from chapter 3, climate data and other environmental variables. Over the two-decade period, caribou selected middle elevation, open areas with high graminoid cover and earlier snow-free dates. As each winter progressed, caribou aggregated where there was higher lichen cover and earlier snow-melt. Caribou selected habitat differently between years, which I collapsed into three different habitat/year groups: (1) years where most animals were in low elevation, flat terrain where there was low lichen and conifer cover but high graminoid and shrub cover with variable snow; (2) years caribou went to middle elevations with deeper snow and rugged terrain and moderate graminoid and lichen cover; and (3) years where caribou were dispersed west in low elevation woodlands with high lichen cover. My results show interacting factors determine caribou habitat selection at multiple spatial scales, specifically the importance of open, tussock tundra and long-term trends in snow melt at long time scales and lichen and snow-melt at shorter time scales. This research improves our understanding of the regional distribution and abundance of lichens in relation to higher plants, fire, and caribou. Close

• 499. [Article] Quantification of Ecological Change Using Repeat Photography and Ground Based Lidar

  Remote sensing techniques have long been useful in quantifying changes in ecosystems and the field of remote sensing is constantly evolving to better assess and describe changes, both spatially and temporally. ...

  Citation × Citation Citation Abstract Copy Title: Quantification of Ecological Change Using Repeat Photography and Ground Based Lidar Author: Batchelor, Jonathan L. Remote sensing techniques have long been useful in quantifying changes in ecosystems and the field of remote sensing is constantly evolving to better assess and describe changes, both spatially and temporally. In this thesis I explored the novel use of two remote sensing methods to quantify ecosystems; repeat photograph to describe change over time, and ground based lidar to describe change spatially. Using repeat photography, I assessed the effects of the removal of livestock in riparian systems at Hart Mountain National Antelope Refuge in southeastern Oregon, 23 years after the cessation of cattle grazing. I compared photos taken before grazing was ended with later retake photos. Two methods were used for this assessment: 1) a qualitative visual method comparing seven cover types and processes and 2) a new quantitative method of inserting digital line transects into photos. Results indicated that channel widths and eroding banks decreased in 64% and 73% of sites, respectively. I found a 90% decrease in the amount of bare soil (p<0.001) and a 63 % decrease in exposed channel (p<0.001) as, well as a significant increase in the cover of grasses/sedges/forbs (15% increase, p=0.037), rushes (389% increase, p=0.014) and willow (388% increase, P<0.001). I also assessed the accuracy of the new method of inserting digital line transects into photo pairs. An overall accuracy of 91% (kappa 83%) suggests digital line transects can be a useful tool for quantifying vegetation cover from photos. My results indicate that the removal of cattle can result in dramatic changes in riparian vegetation, even in semi-arid landscapes and without active restoration treatments. I used ground based lidar to quantify forest structure in a spatially explicit manner. The structural complexity of a forest has profound influences on its ecological functioning and overall health. The arrangement and amount of aboveground biomass are two important components of this structural complexity that influence the biodiversity in a forest ecosystem. In this paper, I explored and develop novel depth and openness metrics derived from single point ground-based lidar scans, which can quantify this complexity to a higher level of detail. Depth is a 3D, radial measure of the visible distance in all directions from a location (e.g., at the scanner origin). Openness is the percent of scan pulses in the near-omnidirectional view without a return,. To derive these metrics, I collected 243 scans at 27 forested stands in the Pacific Northwest region of the United States, representing a broad range of forest structure types. I created structural signatures using depth and openness for each stand and determined that our metrics could reliably differentiate forests. These metrics were compared to several traditional metrics: diameter at breast height (DBH), basal area, and diameter diversity index (DDI). The mean and variance in DBH of trees, basal area, and DDI of each stand were determined by generating isovists (polygons measuring visible space from a location) derived from point cloud cross sections. Interestingly, there was only weak to moderate correlation observed between depth or openness metrics when compared with the mean and variance in DBH, basal area, and DDI, suggesting that our new metrics (depth and openness) quantify a wider range of aspects of structure at the stand and plot level that are not captured by those traditional metrics. The proposed metrics can quantify forest structure at a high level of precision, reduce observer bias, and preserve a level of complexity lost in simple indices. The proposed metrics have great potential for quantifying change in forested systems, and describing habitat for organisms. Title: Quantification of Ecological Change Using Repeat Photography and Ground Based Lidar Author: Batchelor, Jonathan L. Remote sensing techniques have long been useful in quantifying changes in ecosystems and the field of remote sensing is constantly evolving to better assess and describe changes, both spatially and temporally. In this thesis I explored the novel use of two remote sensing methods to quantify ecosystems; repeat photograph to describe change over time, and ground based lidar to describe change spatially. Using repeat photography, I assessed the effects of the removal of livestock in riparian systems at Hart Mountain National Antelope Refuge in southeastern Oregon, 23 years after the cessation of cattle grazing. I compared photos taken before grazing was ended with later retake photos. Two methods were used for this assessment: 1) a qualitative visual method comparing seven cover types and processes and 2) a new quantitative method of inserting digital line transects into photos. Results indicated that channel widths and eroding banks decreased in 64% and 73% of sites, respectively. I found a 90% decrease in the amount of bare soil (p<0.001) and a 63 % decrease in exposed channel (p<0.001) as, well as a significant increase in the cover of grasses/sedges/forbs (15% increase, p=0.037), rushes (389% increase, p=0.014) and willow (388% increase, P<0.001). I also assessed the accuracy of the new method of inserting digital line transects into photo pairs. An overall accuracy of 91% (kappa 83%) suggests digital line transects can be a useful tool for quantifying vegetation cover from photos. My results indicate that the removal of cattle can result in dramatic changes in riparian vegetation, even in semi-arid landscapes and without active restoration treatments. I used ground based lidar to quantify forest structure in a spatially explicit manner. The structural complexity of a forest has profound influences on its ecological functioning and overall health. The arrangement and amount of aboveground biomass are two important components of this structural complexity that influence the biodiversity in a forest ecosystem. In this paper, I explored and develop novel depth and openness metrics derived from single point ground-based lidar scans, which can quantify this complexity to a higher level of detail. Depth is a 3D, radial measure of the visible distance in all directions from a location (e.g., at the scanner origin). Openness is the percent of scan pulses in the near-omnidirectional view without a return,. To derive these metrics, I collected 243 scans at 27 forested stands in the Pacific Northwest region of the United States, representing a broad range of forest structure types. I created structural signatures using depth and openness for each stand and determined that our metrics could reliably differentiate forests. These metrics were compared to several traditional metrics: diameter at breast height (DBH), basal area, and diameter diversity index (DDI). The mean and variance in DBH of trees, basal area, and DDI of each stand were determined by generating isovists (polygons measuring visible space from a location) derived from point cloud cross sections. Interestingly, there was only weak to moderate correlation observed between depth or openness metrics when compared with the mean and variance in DBH, basal area, and DDI, suggesting that our new metrics (depth and openness) quantify a wider range of aspects of structure at the stand and plot level that are not captured by those traditional metrics. The proposed metrics can quantify forest structure at a high level of precision, reduce observer bias, and preserve a level of complexity lost in simple indices. The proposed metrics have great potential for quantifying change in forested systems, and describing habitat for organisms. Close

• 500. [Article] Studies toward the synthesis of coibamide A and analogues

  Coibamide A is a highly methylated cyclic depsipeptide isolated from Panamanian marine filamentous cyanobacteria as part of an International Cooperative Biodiversity Groups (ICBG) program based in Panama. ...

  Citation × Citation Citation Abstract Copy Title: Studies toward the synthesis of coibamide A and analogues Author: Li, Dong Coibamide A is a highly methylated cyclic depsipeptide isolated from Panamanian marine filamentous cyanobacteria as part of an International Cooperative Biodiversity Groups (ICBG) program based in Panama. This structurally unique agent exhibits potent cancer cell toxicity with an unprecedented selectivity profile in the National Cancer Institute (NCI) 60 cell line panel, possibly through a novel mechanism as suggested by "COMPARE negative" results. Therefore, it is considered a promising lead agent in cancer drug discovery. Although field recollections have provided a few milligrams of coibamide A, the amount obtained is still insufficient for extensive biological testing. The producing strain has recently been cultured, but coibamide yields are very low and the growth rate is slow. Chemical synthesis of coibamide A is central to further biological testing and potential clinical development, and has become the major focus of my work. A macrocycle-side chain strategy was originally proposed for the synthesis of coibamide A. It was unsuccessful, however, due to the difficulties trying to couple the macrocycle and side chain together at the last step. To solve this problem, a modified macrocycle – side chain stragety was proposed. Coibamide A was disconnected into two other subunits: the N-MeLeu-macrocycle and the "tripeptide" side chain. The reason for this modification was that the secondary amine of N-MeLeu, with some distance from the bulky macrocycle, should be spatially more availalbe for the final step to couple with the side chain "tripeptide". This new strategy was able to generate "synthetic coibamide" in a moderate yield, this compound, however, was not the natural product coibamide A according to HPLC, 1H NMR and activity test. By Marfey's analysis, we found that in this synthetic coibamide A, no N,O-diMe L-Ser was detected and only its D-counterpart was present, which indicated an unusual L-to-D inversion during coupling reactions. Because it was very difficult to overcome this unexpected inversion during this strategy, a third scheme, the Y-Strategy, was proposed. For the Y-strategy, instead of building the macrocycle first, we coupled the side chain with a macrocycle tripeptide first to afford a linear heptapeptide. Then the ester bond between the hydroxy of N-MeThr and carboxy of N-MeAla (of a tetrapeptide) was built to generate the full-size "Y-structure", which is then deprotected and cyclized to produce the target molecule coibamide A. While the heptapeptide was synthesized sucessfully, the ester bond formation reaction to generate the Y-structure did not happen. Although the Y-strategy did not eventually yield coibamide, it is the most convergent and efficient strategy so far. Because the pharmacological data for coibamide A suggest a unique mechanism and no natural coibamide analogues were separated from the field collections or cultures, the synthesis of coibamide analogues is also extremely valueable for activity and mechanism studies and becomes part of our synthetic effort. The analogues should reasonably resemble the structure of coibamide A, and be easier to be achieved synthetically compared to coibamide A itself. Two families of analogues were designed: the N-desmethyl coibamide family (most or all of the N-methylated amino acid components were replaced by regular amino acids) and the N-MeSer coibamide family (the junction N-MeThr was changed to N-MeSer). Per-N-desmethyl coibamide and several other analogues from the first family were synthesized by the modified macrocycle - side chain strategy, however, none of them exhibits any activity against the testing cell lines. Attempt to per-methylate these compounds also failed due to decomposition of substrates under basic conditions. N-MeSer-coibamide was successfully synthesized through the Y-strategy and purified by HPLC. Cell toxicity has been observed in the activity test, although the potency was several hundred times lower than the natural coibamide A. The synthetic process of N-MeSer coibamide should be optimized for better yields and easier purification as the focus of next stage. Title: Studies toward the synthesis of coibamide A and analogues Author: Li, Dong Coibamide A is a highly methylated cyclic depsipeptide isolated from Panamanian marine filamentous cyanobacteria as part of an International Cooperative Biodiversity Groups (ICBG) program based in Panama. This structurally unique agent exhibits potent cancer cell toxicity with an unprecedented selectivity profile in the National Cancer Institute (NCI) 60 cell line panel, possibly through a novel mechanism as suggested by "COMPARE negative" results. Therefore, it is considered a promising lead agent in cancer drug discovery. Although field recollections have provided a few milligrams of coibamide A, the amount obtained is still insufficient for extensive biological testing. The producing strain has recently been cultured, but coibamide yields are very low and the growth rate is slow. Chemical synthesis of coibamide A is central to further biological testing and potential clinical development, and has become the major focus of my work. A macrocycle-side chain strategy was originally proposed for the synthesis of coibamide A. It was unsuccessful, however, due to the difficulties trying to couple the macrocycle and side chain together at the last step. To solve this problem, a modified macrocycle – side chain stragety was proposed. Coibamide A was disconnected into two other subunits: the N-MeLeu-macrocycle and the "tripeptide" side chain. The reason for this modification was that the secondary amine of N-MeLeu, with some distance from the bulky macrocycle, should be spatially more availalbe for the final step to couple with the side chain "tripeptide". This new strategy was able to generate "synthetic coibamide" in a moderate yield, this compound, however, was not the natural product coibamide A according to HPLC, 1H NMR and activity test. By Marfey's analysis, we found that in this synthetic coibamide A, no N,O-diMe L-Ser was detected and only its D-counterpart was present, which indicated an unusual L-to-D inversion during coupling reactions. Because it was very difficult to overcome this unexpected inversion during this strategy, a third scheme, the Y-Strategy, was proposed. For the Y-strategy, instead of building the macrocycle first, we coupled the side chain with a macrocycle tripeptide first to afford a linear heptapeptide. Then the ester bond between the hydroxy of N-MeThr and carboxy of N-MeAla (of a tetrapeptide) was built to generate the full-size "Y-structure", which is then deprotected and cyclized to produce the target molecule coibamide A. While the heptapeptide was synthesized sucessfully, the ester bond formation reaction to generate the Y-structure did not happen. Although the Y-strategy did not eventually yield coibamide, it is the most convergent and efficient strategy so far. Because the pharmacological data for coibamide A suggest a unique mechanism and no natural coibamide analogues were separated from the field collections or cultures, the synthesis of coibamide analogues is also extremely valueable for activity and mechanism studies and becomes part of our synthetic effort. The analogues should reasonably resemble the structure of coibamide A, and be easier to be achieved synthetically compared to coibamide A itself. Two families of analogues were designed: the N-desmethyl coibamide family (most or all of the N-methylated amino acid components were replaced by regular amino acids) and the N-MeSer coibamide family (the junction N-MeThr was changed to N-MeSer). Per-N-desmethyl coibamide and several other analogues from the first family were synthesized by the modified macrocycle - side chain strategy, however, none of them exhibits any activity against the testing cell lines. Attempt to per-methylate these compounds also failed due to decomposition of substrates under basic conditions. N-MeSer-coibamide was successfully synthesized through the Y-strategy and purified by HPLC. Cell toxicity has been observed in the activity test, although the potency was several hundred times lower than the natural coibamide A. The synthetic process of N-MeSer coibamide should be optimized for better yields and easier purification as the focus of next stage. Close