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• 71. [Article] Forest structure and composition changes in a tropical montane cloud forest surrounding an illegal village in Bale Mountains National Park : anthropogenic disturbance along forest resource trails and implications for conservation and management

  Bale Mountains National Park (BMNP) is currently considered the most important conservation area in Ethiopia. BMNP was established over forty years ago to protect Ethiopian endemic fauna and to preserve ...

  Citation × Citation Citation Abstract Copy Title: Forest structure and composition changes in a tropical montane cloud forest surrounding an illegal village in Bale Mountains National Park : anthropogenic disturbance along forest resource trails and implications for conservation and management Author: Arechiga, Theresa Ramona Bale Mountains National Park (BMNP) is currently considered the most important conservation area in Ethiopia. BMNP was established over forty years ago to protect Ethiopian endemic fauna and to preserve an array of habitat types including Afroalpine, Afromontane, and the second largest natural humid forest (Harenna forest) left in Ethiopia. In the 1980’s and 1990’s assertions of a potential seasonal tropical montane cloud forest were made concerning areas in the upper Harenna forest. Despite these claims no additional evidence or research has been provided to verify the presence of a tropical montane cloud forest. Since the initial claims BMNP has faced increasing human and livestock population growth throughout the park including the elevation belt believed to contain the tropical montane cloud forest. This observational study was undertaken in Rira, the largest permanent village in the 2700 m to 3200 m above sea level belt. There were two goals to this research: one, to document rainfall amounts, temperature averages, and provide evidence of forest structure and characteristics consistent with tropical montane cloud forests; second, to identify the strongest detectible gradients affecting current forest structure and composition of herbaceous, shrub, and tree communities. A stationary weather station was installed at BMNP Subheadquarters at 2800 m to collect pertinent weather data. Variable-radius plots and fixed area plots were used along forest resource trails to collect the vegetation data. Nonmetric Multi-dimensional Scaling (NMS) was used to identify important gradients affecting forest structure and composition in the forest surrounding Rira. The vegetation matrix consisted of percent cover for the herbaceous layer, basal area and count for shrubs, basal area and size classification information for the trees, which resulted in a 15 plot x 96 species matrix. Twenty-three environmental and anthropogenic variables were used in a second matrix to identify primary gradients influencing the vegetation structure and composition. Average monthly rainfall in Rira was 673 mm based on 18 months of rainfall data. The overall forest canopy height and physical characteristics are consistent with tropical montane cloud forests. These findings suggest that the upper portion of the Harenna forest should be officially classified as tropical montane cloud forest. The primary gradient affecting forest structure and composition was consistent with anthropogenic disturbance. The variables which were statistically significant covariates included herbaceous layer height, distance to village, and presence of fuel wood collection with Pearson’s r (13) = -0.86, -0.84, 0.82, p<0.05 respectively. Due to the small sample size additional studies are required to clarify and understand the anthropogenic disturbance trends identified in this research. Studies concerning weather and to verify the role the Harenna forest plays in moderating moisture outflow to surrounding lowlands areas could provide additional incentives for conservation and management strategies. Title: Forest structure and composition changes in a tropical montane cloud forest surrounding an illegal village in Bale Mountains National Park : anthropogenic disturbance along forest resource trails and implications for conservation and management Author: Arechiga, Theresa Ramona Bale Mountains National Park (BMNP) is currently considered the most important conservation area in Ethiopia. BMNP was established over forty years ago to protect Ethiopian endemic fauna and to preserve an array of habitat types including Afroalpine, Afromontane, and the second largest natural humid forest (Harenna forest) left in Ethiopia. In the 1980’s and 1990’s assertions of a potential seasonal tropical montane cloud forest were made concerning areas in the upper Harenna forest. Despite these claims no additional evidence or research has been provided to verify the presence of a tropical montane cloud forest. Since the initial claims BMNP has faced increasing human and livestock population growth throughout the park including the elevation belt believed to contain the tropical montane cloud forest. This observational study was undertaken in Rira, the largest permanent village in the 2700 m to 3200 m above sea level belt. There were two goals to this research: one, to document rainfall amounts, temperature averages, and provide evidence of forest structure and characteristics consistent with tropical montane cloud forests; second, to identify the strongest detectible gradients affecting current forest structure and composition of herbaceous, shrub, and tree communities. A stationary weather station was installed at BMNP Subheadquarters at 2800 m to collect pertinent weather data. Variable-radius plots and fixed area plots were used along forest resource trails to collect the vegetation data. Nonmetric Multi-dimensional Scaling (NMS) was used to identify important gradients affecting forest structure and composition in the forest surrounding Rira. The vegetation matrix consisted of percent cover for the herbaceous layer, basal area and count for shrubs, basal area and size classification information for the trees, which resulted in a 15 plot x 96 species matrix. Twenty-three environmental and anthropogenic variables were used in a second matrix to identify primary gradients influencing the vegetation structure and composition. Average monthly rainfall in Rira was 673 mm based on 18 months of rainfall data. The overall forest canopy height and physical characteristics are consistent with tropical montane cloud forests. These findings suggest that the upper portion of the Harenna forest should be officially classified as tropical montane cloud forest. The primary gradient affecting forest structure and composition was consistent with anthropogenic disturbance. The variables which were statistically significant covariates included herbaceous layer height, distance to village, and presence of fuel wood collection with Pearson’s r (13) = -0.86, -0.84, 0.82, p<0.05 respectively. Due to the small sample size additional studies are required to clarify and understand the anthropogenic disturbance trends identified in this research. Studies concerning weather and to verify the role the Harenna forest plays in moderating moisture outflow to surrounding lowlands areas could provide additional incentives for conservation and management strategies. Close

• 72. [Article] Strategies for reducing irrigation water use

  Published July 2001. A more recent revision exists. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://ex...

  Citation × Citation Citation Abstract Copy Title: Strategies for reducing irrigation water use Author: Oregon State University. Extension Service, Shock, C. C. (Clinton C.), Jensen, Lynn Published July 2001. A more recent revision exists. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Strategies for reducing irrigation water use Author: Oregon State University. Extension Service, Shock, C. C. (Clinton C.), Jensen, Lynn Published July 2001. A more recent revision exists. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 73. [Article] The roles of provenance and phylogeny in recruitment, community assembly, and species coexistence in invaded California grasslands

  Biological invasions pose one of the greatest threats to global biodiversity, but many naturalized invaders coexist with the native community. Community ecology theory provides a framework for understanding ...

  Citation × Citation Citation Abstract Copy Title: The roles of provenance and phylogeny in recruitment, community assembly, and species coexistence in invaded California grasslands Author: Brandt, Angela J. Biological invasions pose one of the greatest threats to global biodiversity, but many naturalized invaders coexist with the native community. Community ecology theory provides a framework for understanding the mechanisms by which invaders might coexist with native species or exclude them from the community, thus informing management practices to maximize their effectiveness at conserving native biodiversity. Differences in functional or phylogenetic similarity of invaders to native residents can affect invasion success and the probability they will coexist with natives. For example, functionally dissimilar species may not compete strongly and distantly related species may share fewer natural enemies. Furthermore, environmental heterogeneity can promote species coexistence by providing the opportunity for a greater number of coexistence mechanisms to operate, thereby mitigating the potential for species invasions to lead to native extinction. My thesis examines how provenance (i.e., native origin) and phylogenetic relatedness of plant species affect community dynamics and species interactions in the invaded California grasslands. To do this I have assembled two unique community data sets, one spanning 48 years across a 1000-ha site and one spanning 7 years along a 500-km latitudinal transect. I show that native and exotic species abundance and diversity is highly variable in both time and space, but these provenance group responses are rarely negatively correlated (Chapter 2). Thus, exotic species do not generally appear to exclude natives from communities. Long-term abundance patterns further suggest that the system remains in a state of transience, and populations of several native species are declining at local scales (Chapter 3). Recruitment limitation due to the build-up of plant litter associated with exotic grasses may be generally responsible for these declines, but habitat suitability, land-use history, and community composition also affect native recruitment. Across the grasslands, disturbance and resource supply can interact to affect both species and phylogenetic diversity (Chapter 4). Disturbance in particular can increase diversity, likely by increasing opportunities for colonization by removing plant litter that previously limited recruitment. Both phylogeny and provenance can also affect biotic interactions, such as with communities of soil organisms (Chapter 5). Thus, I have shown that spatio-temporal heterogeneity, alterations to the biotic environment mediated by exotic invasion, and phylogenetic relationships among species are all important considerations when evaluating impacts of invasion and designing management strategies to conserve native biodiversity, especially in light of anthropogenic influence on disturbance regimes and resource supply. Title: The roles of provenance and phylogeny in recruitment, community assembly, and species coexistence in invaded California grasslands Author: Brandt, Angela J. Biological invasions pose one of the greatest threats to global biodiversity, but many naturalized invaders coexist with the native community. Community ecology theory provides a framework for understanding the mechanisms by which invaders might coexist with native species or exclude them from the community, thus informing management practices to maximize their effectiveness at conserving native biodiversity. Differences in functional or phylogenetic similarity of invaders to native residents can affect invasion success and the probability they will coexist with natives. For example, functionally dissimilar species may not compete strongly and distantly related species may share fewer natural enemies. Furthermore, environmental heterogeneity can promote species coexistence by providing the opportunity for a greater number of coexistence mechanisms to operate, thereby mitigating the potential for species invasions to lead to native extinction. My thesis examines how provenance (i.e., native origin) and phylogenetic relatedness of plant species affect community dynamics and species interactions in the invaded California grasslands. To do this I have assembled two unique community data sets, one spanning 48 years across a 1000-ha site and one spanning 7 years along a 500-km latitudinal transect. I show that native and exotic species abundance and diversity is highly variable in both time and space, but these provenance group responses are rarely negatively correlated (Chapter 2). Thus, exotic species do not generally appear to exclude natives from communities. Long-term abundance patterns further suggest that the system remains in a state of transience, and populations of several native species are declining at local scales (Chapter 3). Recruitment limitation due to the build-up of plant litter associated with exotic grasses may be generally responsible for these declines, but habitat suitability, land-use history, and community composition also affect native recruitment. Across the grasslands, disturbance and resource supply can interact to affect both species and phylogenetic diversity (Chapter 4). Disturbance in particular can increase diversity, likely by increasing opportunities for colonization by removing plant litter that previously limited recruitment. Both phylogeny and provenance can also affect biotic interactions, such as with communities of soil organisms (Chapter 5). Thus, I have shown that spatio-temporal heterogeneity, alterations to the biotic environment mediated by exotic invasion, and phylogenetic relationships among species are all important considerations when evaluating impacts of invasion and designing management strategies to conserve native biodiversity, especially in light of anthropogenic influence on disturbance regimes and resource supply. Close

• 74. [Article] Larval dispersal in marine fishes: novel methods reveal patterns of self-recruitment and population connectivity

  Many marine fish populations are severely declining due to over-fishing, loss of both juvenile and adult habitats, and accelerating environmental degradation. Fisheries management and the implementation ...

  Citation × Citation Citation Abstract Copy Title: Larval dispersal in marine fishes: novel methods reveal patterns of self-recruitment and population connectivity Author: Christie, Mark R. Many marine fish populations are severely declining due to over-fishing, loss of both juvenile and adult habitats, and accelerating environmental degradation. Fisheries management and the implementation of marine protected areas (MPAs) and other conservation tools are currently hindered by large gaps in knowledge about larval dispersal and its subsequent effects on population dynamics and regulation. This lack of knowledge is due to the inherent difficulty associated with tracking miniscule marine fish larvae. Population genetics approaches are particularly promising, but current methods have been of limited use for inferring ecologically relevant rates of population connectivity because of the large population sizes and high amounts of gene flow present in most marine species. To address these issues, I developed novel genetic methods of identifying parent-offspring pairs to directly track the origin and settlement of larvae in natural populations. These parentage methods fully account for large numbers of pair-wise comparisons and do not require any demographic assumptions or observational data. Furthermore, these methods can be used when only a small proportion of candidate parents can be sampled, which is often the case in large marine populations. I also employed Bayes’ theorem to take into account the frequencies of shared alleles in putative parent-offspring pairs, which can maximize statistical power when faced with fixed numbers of loci. I accounted for genotyping errors by introducing a quantitative method to determine the number of loci to allow to mismatch based upon study-specific error rates. These novel parentage methods were applied to yellow tang (Zebrasoma flavescens, Acanthuridae) sampled around the Island of Hawai'i (measuring 140 km by 129 km) during the summer of 2006. We identified four parent-offspring pairs, which documented dispersal distances ranging from 15 to 184 kilometers. Two of the parents were located within MPAs and their offspring dispersed to unprotected areas. This observation provided direct evidence that MPAs can successfully seed unprotected sites with larvae that survive to become established juveniles. All four offspring were found to the north of their parents and a detailed oceanographic analysis from relevant time periods demonstrated that passive transport initially explained the documented dispersal patterns. However, passive dispersal could not explain how larvae eventually settled on the same island from which they were spawned, indicating a role for larval behavior interacting with fine-scale oceanographic features. Two findings together suggested that sampled reefs did not contribute equally to successful recruitment: (1) low levels of genetic differentiation among all recruit samples, and (2) the fact that the 4 documented parents occurred at only 2 sites. These findings empirically demonstrated the effectiveness of MPAs as useful conservation and management tools and highlighted the value of identifying both the sources and successful settlement sites of marine larvae. I next examined patterns of larval dispersal in bicolor damselfish (Stegastes partitus, Pomacentridae) collected during the summers of 2004 and 2005 from reefs lining the Exuma Sound, Bahamas (measuring 205 km by 85 km). Parentage analysis directly documented two parent-offspring pairs located within the two northern-most sites, which indicated self-recruitment at these sites. Multivariate analyses of pair-wise relatedness values confirmed that self-recruitment was common at all sampled populations. I also found evidence of “sweepstakes events”, whereby only a small proportion of mature adults contributed to subsequent generations. Independent sweepstakes events were indentified in both space and time, bolstering the direct observations of self-recruitment and suggesting a role for sweepstakes analyses to identify the scale of larval dispersal events. This dissertation provides insights into the patterns of larval dispersal in coral-reef fishes. The coupling of direct (e.g., parentage) and indirect (e.g., assignment methods, sweepstakes analyses) methods in conjunction with continued technological and methodological advances will soon provide large-scale, ecologically relevant, rates of larval exchange. By uncovering the dynamics of these enigmatic processes, the implementation of conservation and management strategies for marine fishes in general will undoubtedly experience greater success. Title: Larval dispersal in marine fishes: novel methods reveal patterns of self-recruitment and population connectivity Author: Christie, Mark R. Many marine fish populations are severely declining due to over-fishing, loss of both juvenile and adult habitats, and accelerating environmental degradation. Fisheries management and the implementation of marine protected areas (MPAs) and other conservation tools are currently hindered by large gaps in knowledge about larval dispersal and its subsequent effects on population dynamics and regulation. This lack of knowledge is due to the inherent difficulty associated with tracking miniscule marine fish larvae. Population genetics approaches are particularly promising, but current methods have been of limited use for inferring ecologically relevant rates of population connectivity because of the large population sizes and high amounts of gene flow present in most marine species. To address these issues, I developed novel genetic methods of identifying parent-offspring pairs to directly track the origin and settlement of larvae in natural populations. These parentage methods fully account for large numbers of pair-wise comparisons and do not require any demographic assumptions or observational data. Furthermore, these methods can be used when only a small proportion of candidate parents can be sampled, which is often the case in large marine populations. I also employed Bayes’ theorem to take into account the frequencies of shared alleles in putative parent-offspring pairs, which can maximize statistical power when faced with fixed numbers of loci. I accounted for genotyping errors by introducing a quantitative method to determine the number of loci to allow to mismatch based upon study-specific error rates. These novel parentage methods were applied to yellow tang (Zebrasoma flavescens, Acanthuridae) sampled around the Island of Hawai'i (measuring 140 km by 129 km) during the summer of 2006. We identified four parent-offspring pairs, which documented dispersal distances ranging from 15 to 184 kilometers. Two of the parents were located within MPAs and their offspring dispersed to unprotected areas. This observation provided direct evidence that MPAs can successfully seed unprotected sites with larvae that survive to become established juveniles. All four offspring were found to the north of their parents and a detailed oceanographic analysis from relevant time periods demonstrated that passive transport initially explained the documented dispersal patterns. However, passive dispersal could not explain how larvae eventually settled on the same island from which they were spawned, indicating a role for larval behavior interacting with fine-scale oceanographic features. Two findings together suggested that sampled reefs did not contribute equally to successful recruitment: (1) low levels of genetic differentiation among all recruit samples, and (2) the fact that the 4 documented parents occurred at only 2 sites. These findings empirically demonstrated the effectiveness of MPAs as useful conservation and management tools and highlighted the value of identifying both the sources and successful settlement sites of marine larvae. I next examined patterns of larval dispersal in bicolor damselfish (Stegastes partitus, Pomacentridae) collected during the summers of 2004 and 2005 from reefs lining the Exuma Sound, Bahamas (measuring 205 km by 85 km). Parentage analysis directly documented two parent-offspring pairs located within the two northern-most sites, which indicated self-recruitment at these sites. Multivariate analyses of pair-wise relatedness values confirmed that self-recruitment was common at all sampled populations. I also found evidence of “sweepstakes events”, whereby only a small proportion of mature adults contributed to subsequent generations. Independent sweepstakes events were indentified in both space and time, bolstering the direct observations of self-recruitment and suggesting a role for sweepstakes analyses to identify the scale of larval dispersal events. This dissertation provides insights into the patterns of larval dispersal in coral-reef fishes. The coupling of direct (e.g., parentage) and indirect (e.g., assignment methods, sweepstakes analyses) methods in conjunction with continued technological and methodological advances will soon provide large-scale, ecologically relevant, rates of larval exchange. By uncovering the dynamics of these enigmatic processes, the implementation of conservation and management strategies for marine fishes in general will undoubtedly experience greater success. Close

• 75. [Article] Fire effects on wetland prairie species: final report

  Project No. 14-48-0001-96749

  Citation × Citation Citation Abstract Copy Title: Fire effects on wetland prairie species: final report Author: Wilson, Mark V., Clark, Deborah Louise, 1950- Project No. 14-48-0001-96749 Title: Fire effects on wetland prairie species: final report Author: Wilson, Mark V., Clark, Deborah Louise, 1950- Project No. 14-48-0001-96749 Close

• 76. [Article] Topology independent transmission scheduling algorithms in mobile ad hoc networks

  Due to the rapid growth of wireless technology, there has been a growing interest in the capabilities of ad hoc networks connecting mobile phones, PDAs and laptop computers. The distributed and self-configurable ...

  Citation × Citation Citation Abstract Copy Title: Topology independent transmission scheduling algorithms in mobile ad hoc networks Author: Youn, Jong-Hoon Due to the rapid growth of wireless technology, there has been a growing interest in the capabilities of ad hoc networks connecting mobile phones, PDAs and laptop computers. The distributed and self-configurable capabilities of ad hoc networks make them very attractive for some applications such as tactical communication for military, search and rescue mission, disaster recovery, conferences, lectures, etc. In this thesis, we describe several new time scheduling algorithms for multihop packet radio networks; MaxThrou, MinDelay, ECTS (Energy Conserving Transmission Scheduling) and LA-TSMA (Location-Aided Time-Spread Multiple-Access). The MaxThrou and MinDelay algorithms focus on maximizing the system throughput and minimizing the delay bound by using constant weight codes. In these algorithms, each mobile host is assigned a word from an appropriate constant weight code of length n, distance d and weight w. The host can send a message at the j[superscript th] slot provided the assigned code has a 1 in this j[superscript th] bit. The MaxThrou and MinDelay scheduling algorithms are better than the previously known algorithms in terms of the minimum throughput per node and/or the delay bound. Since most of mobile hosts are operated using the scarce battery, and the battery life is not expected to increase significantly in the near future, energy efficiency is a critical issue in ad hoc networks. The ECTS algorithm conserves the power using strategies that allow the network interface to use the low power sleep mode instead of the idle mode, and also eliminates data collisions by introducing Request-To-Send (RTS) and Clear-To-Send (CTS) control slots. Simulation study shows that the ECTS algorithm outperforms previously known protocols. Due to the increasing popularity of mobile networking systems, the scalability becomes a significant new challenge for ad hoc network protocols. To provide a scalable solution for mobile ad hoc networks, we introduce the LA-TSMA algorithm. Instead of assigning a globally unique TSV to each host as done in previous topology-transparent scheduling algorithms, the proposed algorithm assigns a locally unique TSV to each host. In LA-TSMA, a territory is divided into zones, and the mobile hosts located in different zones can be assigned the same TSV. Title: Topology independent transmission scheduling algorithms in mobile ad hoc networks Author: Youn, Jong-Hoon Due to the rapid growth of wireless technology, there has been a growing interest in the capabilities of ad hoc networks connecting mobile phones, PDAs and laptop computers. The distributed and self-configurable capabilities of ad hoc networks make them very attractive for some applications such as tactical communication for military, search and rescue mission, disaster recovery, conferences, lectures, etc. In this thesis, we describe several new time scheduling algorithms for multihop packet radio networks; MaxThrou, MinDelay, ECTS (Energy Conserving Transmission Scheduling) and LA-TSMA (Location-Aided Time-Spread Multiple-Access). The MaxThrou and MinDelay algorithms focus on maximizing the system throughput and minimizing the delay bound by using constant weight codes. In these algorithms, each mobile host is assigned a word from an appropriate constant weight code of length n, distance d and weight w. The host can send a message at the j[superscript th] slot provided the assigned code has a 1 in this j[superscript th] bit. The MaxThrou and MinDelay scheduling algorithms are better than the previously known algorithms in terms of the minimum throughput per node and/or the delay bound. Since most of mobile hosts are operated using the scarce battery, and the battery life is not expected to increase significantly in the near future, energy efficiency is a critical issue in ad hoc networks. The ECTS algorithm conserves the power using strategies that allow the network interface to use the low power sleep mode instead of the idle mode, and also eliminates data collisions by introducing Request-To-Send (RTS) and Clear-To-Send (CTS) control slots. Simulation study shows that the ECTS algorithm outperforms previously known protocols. Due to the increasing popularity of mobile networking systems, the scalability becomes a significant new challenge for ad hoc network protocols. To provide a scalable solution for mobile ad hoc networks, we introduce the LA-TSMA algorithm. Instead of assigning a globally unique TSV to each host as done in previous topology-transparent scheduling algorithms, the proposed algorithm assigns a locally unique TSV to each host. In LA-TSMA, a territory is divided into zones, and the mobile hosts located in different zones can be assigned the same TSV. Close

• 77. [Article] Linkages between mangrove forests and coral reefs : quantifying disturbance effects and energy flow between systems

  Interface habitats are considered valuable natural systems, tightly linked to adjacent habitats through the flow of matter and energy. However, there is limited research on mechanisms of connectivity such ...

  Citation × Citation Citation Abstract Copy Title: Linkages between mangrove forests and coral reefs : quantifying disturbance effects and energy flow between systems Author: Granek, Elise F. Interface habitats are considered valuable natural systems, tightly linked to adjacent habitats through the flow of matter and energy. However, there is limited research on mechanisms of connectivity such as movement of organisms and particulate matter and ways in which anthropogenic disturbance to interface habitats may affect immediate and adjacent ecosystems. Mangrove forests, a common interface habitat in tropical coastal zones, once lined much of the tropical and subtropical shores worldwide. However, anthropogenic influences on these systems have led to a ~35% reduction in mangrove area over the last fifty years. In light of the perceived importance of mangrove forests as coastal habitat, the rapid decline of this habitat type, and the potential implications of mangrove habitat loss to adjacent ecosystems, it is important to build upon the current state of knowledge for mangrove forests. The chapters in this dissertation report on the following topics. First I review the published literature to examine the available evidence for connections between mangrove forests and coral reefs. I synthesize previous research findings, highlight areas of future research priorities, and propose a conceptual model of how areas of mangrove disturbance and resulting impacts on coral reefs are related. Second, I assess the effects of mangrove clearing on the immediate habitat. I examine how the physical environment changes following mangrove clearing by examining abiotic factors. I also measure changes in algal biomass and diversity to determine what effects physical changes have on the primary producer community. My results indicate that mangrove clearing has dramatic effects on both the physical and biotic environment. Based on measured changes in abiotic and biotic conditions, K. Frasier and I investigate how larval and zooplankton communities differ between intact and cleared mangrove areas. We find that diversity and community composition differ between intact and cleared mangrove areas, highlighting an additional effect of mangrove disturbance with potential implications for adjacent systems. To address the unanswered question of whether and how abiotic and biotic changes in cleared mangrove areas impact adjacent coral reefs, I repeat and expand upon the study I had conducted on abiotic and biotic changes following mangrove removal. The results in the immediate habitat indicate that the effects of mangrove disturbance are broad. Results from the reefs indicate that mangrove disturbance does have effects on adjacent coral reefs. To determine the relative importance of mangrove-derived nutrients to adjacent coral reef ecosystems and to examine how distance from mangroves to reefs and clearing of mangroves affected energy transfer, I sample sessile reef invertebrates. I employ carbon, nitrogen and sulfur stable isotope analysis as a tool to evaluate whether sessile invertebrates: corals, sponges, a bivalve and feather duster worm, utilize mangrovederived nutrients. Though the pattern varies by taxon, this research provides evidence that sessile reef invertebrates utilize mangrove-derived nutrients. Finally, I examine the effect of two consecutive storm events, the 2005 Tropical Storm (later Category 5 Hurricane) Wilma and the subsequent Tropical Storm Gamma, on the coastal zone. The retention rate of field equipment following storm events provides a picture of how coastal protection changes following anthropogenic mangrove disturbance and the implications of continuing mangrove loss as storm frequency and intensity increase in parallel with climate change. These studies provide new evidence on the effects of disturbance to mangroves on coastal and reef systems. Many new research areas are raised by the results presented here. However, these data provide a useful framework for considering conservation and management strategies for mangrove forest – coral reef systems. Title: Linkages between mangrove forests and coral reefs : quantifying disturbance effects and energy flow between systems Author: Granek, Elise F. Interface habitats are considered valuable natural systems, tightly linked to adjacent habitats through the flow of matter and energy. However, there is limited research on mechanisms of connectivity such as movement of organisms and particulate matter and ways in which anthropogenic disturbance to interface habitats may affect immediate and adjacent ecosystems. Mangrove forests, a common interface habitat in tropical coastal zones, once lined much of the tropical and subtropical shores worldwide. However, anthropogenic influences on these systems have led to a ~35% reduction in mangrove area over the last fifty years. In light of the perceived importance of mangrove forests as coastal habitat, the rapid decline of this habitat type, and the potential implications of mangrove habitat loss to adjacent ecosystems, it is important to build upon the current state of knowledge for mangrove forests. The chapters in this dissertation report on the following topics. First I review the published literature to examine the available evidence for connections between mangrove forests and coral reefs. I synthesize previous research findings, highlight areas of future research priorities, and propose a conceptual model of how areas of mangrove disturbance and resulting impacts on coral reefs are related. Second, I assess the effects of mangrove clearing on the immediate habitat. I examine how the physical environment changes following mangrove clearing by examining abiotic factors. I also measure changes in algal biomass and diversity to determine what effects physical changes have on the primary producer community. My results indicate that mangrove clearing has dramatic effects on both the physical and biotic environment. Based on measured changes in abiotic and biotic conditions, K. Frasier and I investigate how larval and zooplankton communities differ between intact and cleared mangrove areas. We find that diversity and community composition differ between intact and cleared mangrove areas, highlighting an additional effect of mangrove disturbance with potential implications for adjacent systems. To address the unanswered question of whether and how abiotic and biotic changes in cleared mangrove areas impact adjacent coral reefs, I repeat and expand upon the study I had conducted on abiotic and biotic changes following mangrove removal. The results in the immediate habitat indicate that the effects of mangrove disturbance are broad. Results from the reefs indicate that mangrove disturbance does have effects on adjacent coral reefs. To determine the relative importance of mangrove-derived nutrients to adjacent coral reef ecosystems and to examine how distance from mangroves to reefs and clearing of mangroves affected energy transfer, I sample sessile reef invertebrates. I employ carbon, nitrogen and sulfur stable isotope analysis as a tool to evaluate whether sessile invertebrates: corals, sponges, a bivalve and feather duster worm, utilize mangrovederived nutrients. Though the pattern varies by taxon, this research provides evidence that sessile reef invertebrates utilize mangrove-derived nutrients. Finally, I examine the effect of two consecutive storm events, the 2005 Tropical Storm (later Category 5 Hurricane) Wilma and the subsequent Tropical Storm Gamma, on the coastal zone. The retention rate of field equipment following storm events provides a picture of how coastal protection changes following anthropogenic mangrove disturbance and the implications of continuing mangrove loss as storm frequency and intensity increase in parallel with climate change. These studies provide new evidence on the effects of disturbance to mangroves on coastal and reef systems. Many new research areas are raised by the results presented here. However, these data provide a useful framework for considering conservation and management strategies for mangrove forest – coral reef systems. Close

• 78. [Article] Oregon strategy for greenhouse gas reductions

  The Governor’s Advisory Group on Global Warming developed this Oregon Strategy for Greenhouse Gas Reduction.1 Governor Ted Kulongoski appointed the Advisory Group early in 2004 to perform this task. This ...

  Citation × Citation Citation Abstract Copy Title: Oregon strategy for greenhouse gas reductions Author: Institute for Natural Resources, Governor's Advisory Group on Global Warming The Governor’s Advisory Group on Global Warming developed this Oregon Strategy for Greenhouse Gas Reduction.1 Governor Ted Kulongoski appointed the Advisory Group early in 2004 to perform this task. This Strategy, if implemented, will complement the agenda of the West Coast Governors’ Global Warming Initiative undertaken by the governors of California, Oregon and Washington to address greenhouse gas emissions at a state and regional level. Title: Oregon strategy for greenhouse gas reductions Author: Institute for Natural Resources, Governor's Advisory Group on Global Warming The Governor’s Advisory Group on Global Warming developed this Oregon Strategy for Greenhouse Gas Reduction.1 Governor Ted Kulongoski appointed the Advisory Group early in 2004 to perform this task. This Strategy, if implemented, will complement the agenda of the West Coast Governors’ Global Warming Initiative undertaken by the governors of California, Oregon and Washington to address greenhouse gas emissions at a state and regional level. Close

• 79. [Article] General management principles and a checklist of strategies to guide forest biodiversity conservation

  Many indicators and criteria have been proposed to assess the sustainable management of forests but their scientific validity remains uncertain. Because the effects of forest disturbances (such as logging) ...

  Citation × Citation Citation Abstract Copy Title: General management principles and a checklist of strategies to guide forest biodiversity conservation Author: Fischer, J., Lindenmayer, D.B., Franklin, J.F. Many indicators and criteria have been proposed to assess the sustainable management of forests but their scientific validity remains uncertain. Because the effects of forest disturbances (such as logging) are often specific to particular species, sites, landscapes, regions and forest types, management ‘‘shortcuts’’ such as indicator species, focal species and threshold levels of vegetation cover may be of limited generic value. We propose an alternative approach based on a set of five guiding principles for biodiversity conservation that are broadly applicable to any forested area: (1) the maintenance of connectivity; (2) the maintenance of landscape heterogeneity; (3) the maintenance of stand structural complexity; and (4) the maintenance of aquatic ecosystem integrity; (5) the use of natural disturbance regimes to guide human disturbance regimes. We present a checklist of measures for forest biodiversity conservation that reflects the multi-scaled nature of conservation approaches on forested land. At the regional scale, management should ensure the establishment of large ecological reserves. At the landscape scale, off-reserve conservation measures should include: (1) protected areas within production forests; (2) buffers for aquatic ecosystems; (3) appropriately designed and located road networks; (4) the careful spatial and temporal arrangement of harvest units; and (5) appropriate fire management practices. At the stand level, off-reserve conservation measures should include: (1) the retention of key elements of stand structural complexity (e.g., large living and dead trees with hollows, understorey thickets, and large fallen logs); (2) long rotation times (coupled with structural retention at harvest); (3) silvicultural systems alternative to traditional high impact ones (e.g., clearcutting in some forest types); and (4) appropriate fire management practices and practices for the management of other kinds of disturbances. Although the general ecological principles and associated checklist are intuitive, data to evaluate the effectiveness of many specific on-the-ground management actions are limited. Considerable effort is needed to adopt adaptive management ‘‘natural experiments’’ and monitoring to: (1) better identify the impacts of logging operations and other kinds of management activities on biodiversity, and; (2) quantify the effectiveness of impact mitigation strategies; and (3) identify ways to improve management practices. Title: General management principles and a checklist of strategies to guide forest biodiversity conservation Author: Fischer, J., Lindenmayer, D.B., Franklin, J.F. Many indicators and criteria have been proposed to assess the sustainable management of forests but their scientific validity remains uncertain. Because the effects of forest disturbances (such as logging) are often specific to particular species, sites, landscapes, regions and forest types, management ‘‘shortcuts’’ such as indicator species, focal species and threshold levels of vegetation cover may be of limited generic value. We propose an alternative approach based on a set of five guiding principles for biodiversity conservation that are broadly applicable to any forested area: (1) the maintenance of connectivity; (2) the maintenance of landscape heterogeneity; (3) the maintenance of stand structural complexity; and (4) the maintenance of aquatic ecosystem integrity; (5) the use of natural disturbance regimes to guide human disturbance regimes. We present a checklist of measures for forest biodiversity conservation that reflects the multi-scaled nature of conservation approaches on forested land. At the regional scale, management should ensure the establishment of large ecological reserves. At the landscape scale, off-reserve conservation measures should include: (1) protected areas within production forests; (2) buffers for aquatic ecosystems; (3) appropriately designed and located road networks; (4) the careful spatial and temporal arrangement of harvest units; and (5) appropriate fire management practices. At the stand level, off-reserve conservation measures should include: (1) the retention of key elements of stand structural complexity (e.g., large living and dead trees with hollows, understorey thickets, and large fallen logs); (2) long rotation times (coupled with structural retention at harvest); (3) silvicultural systems alternative to traditional high impact ones (e.g., clearcutting in some forest types); and (4) appropriate fire management practices and practices for the management of other kinds of disturbances. Although the general ecological principles and associated checklist are intuitive, data to evaluate the effectiveness of many specific on-the-ground management actions are limited. Considerable effort is needed to adopt adaptive management ‘‘natural experiments’’ and monitoring to: (1) better identify the impacts of logging operations and other kinds of management activities on biodiversity, and; (2) quantify the effectiveness of impact mitigation strategies; and (3) identify ways to improve management practices. Close

• 80. [Article] Risk Perceptions and Risk Management Strategies of the Greek Mussel Farmers

  Mussel farming as an aquaculture activity based on the natural primary productivity, faces risks similar to those of the agriculture sector. Consequently, much theoretical risk research has been applied ...

  Citation × Citation Citation Abstract Copy Title: Risk Perceptions and Risk Management Strategies of the Greek Mussel Farmers Author: Tzovenis, Ioannis, Sorgeloos, Patrick, Viaene, Jacques, Theodorou, John A. Mussel farming as an aquaculture activity based on the natural primary productivity, faces risks similar to those of the agriculture sector. Consequently, much theoretical risk research has been applied to aquaculture as in agriculture, livestock, forestry, conservation and its management. Nevertheless, limited studies have so far focused on risk perceptions strategies of the aquaculturists. This study was conducted in the context of Mediterranean mussel farming risk assessment in order to explore the farmers perceptions of risk and risk management, to examine relationships between farm and farmer characteristics, and highlight the prevailing risk perceptions and strategies. The data were collected through a sampling survey of the Greek mussel farmers based on personal questionnaire-interviews. Results show that the ex-farm price of the mussels were perceived to be the major source of risk while the financial/credit reserves were the most preferred risk management strategy. Farmers seem to resort to such practices as the activity is characterized by negligible banking support, production unpredictability, marginal profitability and low turnover, all of these rendering it a high risk activity for the financial institutions. Finally, the farmers’ attitudes and comments on loss compensations bring up the need to develop a more effective and versatile insurance system. Title: Risk Perceptions and Risk Management Strategies of the Greek Mussel Farmers Author: Tzovenis, Ioannis, Sorgeloos, Patrick, Viaene, Jacques, Theodorou, John A. Mussel farming as an aquaculture activity based on the natural primary productivity, faces risks similar to those of the agriculture sector. Consequently, much theoretical risk research has been applied to aquaculture as in agriculture, livestock, forestry, conservation and its management. Nevertheless, limited studies have so far focused on risk perceptions strategies of the aquaculturists. This study was conducted in the context of Mediterranean mussel farming risk assessment in order to explore the farmers perceptions of risk and risk management, to examine relationships between farm and farmer characteristics, and highlight the prevailing risk perceptions and strategies. The data were collected through a sampling survey of the Greek mussel farmers based on personal questionnaire-interviews. Results show that the ex-farm price of the mussels were perceived to be the major source of risk while the financial/credit reserves were the most preferred risk management strategy. Farmers seem to resort to such practices as the activity is characterized by negligible banking support, production unpredictability, marginal profitability and low turnover, all of these rendering it a high risk activity for the financial institutions. Finally, the farmers’ attitudes and comments on loss compensations bring up the need to develop a more effective and versatile insurance system. Close