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• 21. [Article] Ecological effects of post-wildfire management activities (salvage-logging and grass-seeding) on vegetation composition, diversity, biomass, and growth and survival of Pinus ponderosa and Purshia tridentata

  Salvage-logging and artificial seeding of grass following wildfire are common practices in coniferous forests of the western United States, yet few studies have quantified the ecological effects of these ...

  Citation × Citation Citation Abstract Copy Title: Ecological effects of post-wildfire management activities (salvage-logging and grass-seeding) on vegetation composition, diversity, biomass, and growth and survival of Pinus ponderosa and Purshia tridentata Author: Sexton, Timothy Ogden Salvage-logging and artificial seeding of grass following wildfire are common practices in coniferous forests of the western United States, yet few studies have quantified the ecological effects of these post-fire activities. The effects of post-wildfire salvage-logging and grass-seeding on vegetation composition, aboveground biomass, and growth and survival of Pinus ponderosa and Purshia tridentata were quantified on the area burned by the 1992 Lone Pine Fire, Winema National Forest in the Klamath Basin, Oregon. Prior to the fire, the area was dominated by uneven-aged stands of Pinus ponderosa with Purshia tridentata and Stipa occidentalis in the understory. The fire was a stand-replacement disturbance, where the majority of trees, the herbaceous component, and crowns of understory shrubs were killed. Salvage logging resulted in a significant decrease in understory biomass, species richness, species diversity, and growth and survival of P. ponderosa and P. tridentata. In addition plant community composition was shifted from native forb dominance to grass dominance. In 1993, the understory biomass of salvage-logged sites was 38% of the aboveground biomass produced on nonsalvaged sites (322 kg ha^-1 vs 843 kg ha^-1). In 1994, salvage-logged sites produced only 27% of the biomass produced on nonsalvaged sites (402 kg ha^-1 vs 1468 kg ha^-1). Salvage-logging reduced species richness, species diversity, and altered species composition. The first and second years following logging, species richness was reduced by 13% (20 versus 23), and 30% (15 versus 22), respectively. In 1993 and 1994, native forb frequency on nonsalvaged sites was 80% and 77% respectively, while salvage-logged sites recorded 68% and 31% respectively. Conversely, graminoid frequency was significantly higher on salvage-logged sites. In 1994, native graminoid frequency was 35% in nonsalvaged sites and > 61% on salvage-logged sites. During the first two years following salvage-logging, mean height growth of naturally-regenerated Pinus ponderosa was significantly lower on salvaged sites (9.4 versus 7.8 cm yr^-1) as was density of natural Purshia tridentata seedlings (313 versus 530 seedlings ha^-1). Survival in salvage-logged treatments was 22% lower for planted Purshia tridentata seedlings (57% versus 45%). Height growth in salvage-logged treatments was 16% lower for planted Pinus ponderosa (4.4 versus 3.7 cm). Total aboveground biomass on nonsalvaged burned sites (controls) averaged 843 kg ha^-1 in 1993, and 1473 kg ha^-1 in 1994. In 1993, the first year following the fire, sites seeded to Secale cereale produced = 1995 kg ha^-1 total aboveground biomass; most of the biomass was S. cereale. Those seeded sites produced 89% less native forb biomass than controls (82 versus 780 kg ha^-1), and = 80% less native forb biomass than areas seeded to the native grasses Sitanion hystrix and Festuca idahoensis. In 1994, the second post-fire year, biomass on sites seeded to S. cereale was >1653 kg ha^-1, dominated by S. cereale. In 1994, no differences in total aboveground biomass were detected between S. cereale, F idahoensis, S. hystrix, and the Control, indicating that the erosion reducing benefits of grass-seeding did not last for more than one year. Treatments seeded with S. cereale produced 58% less native forb biomass than controls (350 versus 825 kg ha^-1). Seeding S. cereale also reduced by 69% the biomass ofStipa occidentalis, the most common native grass in the area (311 kg ha^-1 on control sites versus 96 kg ha^-1 on S. cereale sites). In 1993 and 1994, fewer species were recorded on S. cereale sites than on all other sites. Grass-seeded sites exhibited no significant differences in frequency of noxious weeds in either of the two years following wildfire and seeding, rejecting the hypothesis that grass-seeding reduces noxious weeds. However, native graminoid frequency was reduced on all grass-seeded treatments. There were no significant differences between grass-seeding treatments in height and density of natural P. ponderosa and P. tridentata seedlings or growth and survival of planted P. ponderosa and P. tridentata seedlings. While salvage-logging provides an economic benefit to local communities through the extraction of commercially valuable timber, there is an ecological cost. Reduction in ecosystem structure, production, species richness, diversity and alterations in species composition are important ecological consequences of salvage logging. In addition, this study demonstrates that salvage-logging retards the re-establishment and early growth of Pinus ponderosa and Purshia tridentata, two important wildfire restoration priorities. Grass-seeding also results in significant ecological changes. Alterations in ecosystem production, species richness, diversity and species composition are important ecological consequences of grass-seeding. Managers should consider these long-term influences on ecosystem composition and structure when faced with decisions concerning post-fire rehabilitation and management. Title: Ecological effects of post-wildfire management activities (salvage-logging and grass-seeding) on vegetation composition, diversity, biomass, and growth and survival of Pinus ponderosa and Purshia tridentata Author: Sexton, Timothy Ogden Salvage-logging and artificial seeding of grass following wildfire are common practices in coniferous forests of the western United States, yet few studies have quantified the ecological effects of these post-fire activities. The effects of post-wildfire salvage-logging and grass-seeding on vegetation composition, aboveground biomass, and growth and survival of Pinus ponderosa and Purshia tridentata were quantified on the area burned by the 1992 Lone Pine Fire, Winema National Forest in the Klamath Basin, Oregon. Prior to the fire, the area was dominated by uneven-aged stands of Pinus ponderosa with Purshia tridentata and Stipa occidentalis in the understory. The fire was a stand-replacement disturbance, where the majority of trees, the herbaceous component, and crowns of understory shrubs were killed. Salvage logging resulted in a significant decrease in understory biomass, species richness, species diversity, and growth and survival of P. ponderosa and P. tridentata. In addition plant community composition was shifted from native forb dominance to grass dominance. In 1993, the understory biomass of salvage-logged sites was 38% of the aboveground biomass produced on nonsalvaged sites (322 kg ha^-1 vs 843 kg ha^-1). In 1994, salvage-logged sites produced only 27% of the biomass produced on nonsalvaged sites (402 kg ha^-1 vs 1468 kg ha^-1). Salvage-logging reduced species richness, species diversity, and altered species composition. The first and second years following logging, species richness was reduced by 13% (20 versus 23), and 30% (15 versus 22), respectively. In 1993 and 1994, native forb frequency on nonsalvaged sites was 80% and 77% respectively, while salvage-logged sites recorded 68% and 31% respectively. Conversely, graminoid frequency was significantly higher on salvage-logged sites. In 1994, native graminoid frequency was 35% in nonsalvaged sites and > 61% on salvage-logged sites. During the first two years following salvage-logging, mean height growth of naturally-regenerated Pinus ponderosa was significantly lower on salvaged sites (9.4 versus 7.8 cm yr^-1) as was density of natural Purshia tridentata seedlings (313 versus 530 seedlings ha^-1). Survival in salvage-logged treatments was 22% lower for planted Purshia tridentata seedlings (57% versus 45%). Height growth in salvage-logged treatments was 16% lower for planted Pinus ponderosa (4.4 versus 3.7 cm). Total aboveground biomass on nonsalvaged burned sites (controls) averaged 843 kg ha^-1 in 1993, and 1473 kg ha^-1 in 1994. In 1993, the first year following the fire, sites seeded to Secale cereale produced = 1995 kg ha^-1 total aboveground biomass; most of the biomass was S. cereale. Those seeded sites produced 89% less native forb biomass than controls (82 versus 780 kg ha^-1), and = 80% less native forb biomass than areas seeded to the native grasses Sitanion hystrix and Festuca idahoensis. In 1994, the second post-fire year, biomass on sites seeded to S. cereale was >1653 kg ha^-1, dominated by S. cereale. In 1994, no differences in total aboveground biomass were detected between S. cereale, F idahoensis, S. hystrix, and the Control, indicating that the erosion reducing benefits of grass-seeding did not last for more than one year. Treatments seeded with S. cereale produced 58% less native forb biomass than controls (350 versus 825 kg ha^-1). Seeding S. cereale also reduced by 69% the biomass ofStipa occidentalis, the most common native grass in the area (311 kg ha^-1 on control sites versus 96 kg ha^-1 on S. cereale sites). In 1993 and 1994, fewer species were recorded on S. cereale sites than on all other sites. Grass-seeded sites exhibited no significant differences in frequency of noxious weeds in either of the two years following wildfire and seeding, rejecting the hypothesis that grass-seeding reduces noxious weeds. However, native graminoid frequency was reduced on all grass-seeded treatments. There were no significant differences between grass-seeding treatments in height and density of natural P. ponderosa and P. tridentata seedlings or growth and survival of planted P. ponderosa and P. tridentata seedlings. While salvage-logging provides an economic benefit to local communities through the extraction of commercially valuable timber, there is an ecological cost. Reduction in ecosystem structure, production, species richness, diversity and alterations in species composition are important ecological consequences of salvage logging. In addition, this study demonstrates that salvage-logging retards the re-establishment and early growth of Pinus ponderosa and Purshia tridentata, two important wildfire restoration priorities. Grass-seeding also results in significant ecological changes. Alterations in ecosystem production, species richness, diversity and species composition are important ecological consequences of grass-seeding. Managers should consider these long-term influences on ecosystem composition and structure when faced with decisions concerning post-fire rehabilitation and management. Close

• 22. [Article] Predictability and Constraints on the Structure of Ecological Communities in the Context of Climate Change

  Ecologists must increasingly balance the need for accurate predictions about how ecosystems will be affected by climate change, against the fact that making such predictions at the ecosystem-level may ...

  Citation × Citation Citation Abstract Copy Title: Predictability and Constraints on the Structure of Ecological Communities in the Context of Climate Change Author: Barner, Allison K. Ecologists must increasingly balance the need for accurate predictions about how ecosystems will be affected by climate change, against the fact that making such predictions at the ecosystem-level may be infeasible. Although information about responses of individual species to a changing environment is increasing, scaling such information to the community level is challenging. To date, predicting responses of ecological communities to climate change is constrained by limited theoretical and empirical knowledge about the response of communities and ecosystems to change. My dissertation addresses several knowledge gaps in our understanding of community structure under climate change. This research draws from a rich experimental tradition in the species-diverse model ecosystem of the US Pacific Northwest rocky intertidal to test ecological theory. In Chapter 2, I assessed whether the response of multiple species of coralline algae to global change could be predicted from basic first principles of chemistry, physiology, and ecology. Given the rate of global change, and the time-consuming process of experimentally determining species responses to climate change, I hypothesized that species can be grouped using existing theory, either by their evolutionary relatedness or by their ecological traits, such that climate responses are similar within a group. Such a scheme would greatly reduce the number of experiments needed to characterize species climate vulnerability, requiring the characterization of the response of groups of species to climate change, rather than individual species. Using a suite of five co-occurring species of intertidal articulated coralline algae (Corallina vancouveriensis, Corallina officinalis, Bossiella plumosa, Bossiella orbiginiana, and Calliarthron tuberculosum), I applied this framework to generate ten mutually exclusive hypotheses that could explain organismal response to ocean acidification, a consequence of global climate change that threatens marine calcifying species. I found that all species had similar responses to ocean acidification, and that responses were generally predicted by the body size of the individual. Despite the power that such a framework provides in understanding group-level response to climate change, predicting community-level response requires knowledge of how organisms affect one another. In Chapter 3, I quantified species interactions in a series of removal experiments to estimate the reciprocal effects between a canopy-forming intertidal kelp (Saccharina sessilis) and a suite of understory species that persist beneath the kelp canopy. This experiment was replicated in different oceanographic conditions across a large latitudinal gradient, as a step towards understanding how interactions might change with climate change. However, the experiment demonstrated that interactions between the canopy and understory were consistent among different environmental conditions. Furthermore, the strongest effect was that of understory species, particularly articulated coralline turf algae, on the canopy species. The coralline turf algae both facilitated the recruitment of the canopy species and buffered the canopy from abiotic stress during its adult life stage. Combining experimental results and observational surveys, a hypothesized interaction network for these species was constructed, highlighting the importance of direct and indirect species interactions in promoting species coexistence. A long-standing controversy in ecology is whether or not species interactions can be inferred from observational data, as opposed to from experimental tests. Although the rocky intertidal ecosystem is unique for its ease of experimental manipulation, quantifying species interactions experimentally is often difficult or impossible. As an alternative, many have turned to statistical methods to estimate species interactions from observational data, namely, from patterns in species pairwise co-occurrences. In Chapter 4, I examined these co-occurrence methods and their potential relationship to experimentally measured species interactions. I first used a suite of different co-occurrence methods to generate a set of predicted species interactions of macrophytes and invertebrates from observational surveys conducted in the rocky intertidal zone of Oregon. I then compared the predicted species interactions to the same pairwise species interactions determined experimentally and assembled from the literature. Overall, of the seven methods tested, each generated a different set of predicted species interactions from the same data, and all methods predicted interactions that did not match those in the experimental database. Thus, predicting species interactions from patterns in occurrence remains elusive. Importantly, much work remains to be done to understand the link between species co-occurrences and their actual interactions with one another on the landscape. A key limiting frontier in climate change ecology is determining the influence of species interactions on species distributions across the landscape, and the sensitivity of such interactions to changes in climate. Finally, in Chapter 5, I used theory from the published literature and knowledge from my previous chapters to make predictions the recovery of low rocky intertidal communities after a disturbance. The process of community development after disturbance has been studied in many ways, from the successional studies of the early 1900s, to modern community assembly theory. In recent years, a focus on the unpredictability of community assembly has emerged, paying particular attention to the role of historical contingency, or priority effects, in determining the recovery trajectory of a community. Priority effects occur when the arrival of a species after a disturbance inalterably changes the composition of the developing community, driving the assembly of widely different communities at a small spatial scale. I conducted a community assembly experiment in three different low intertidal zone community "types", each characterized by different dominant macrophyte species (Saccharina sessilis, Phyllospadix spp., and algal "turfs"). Replicating this experiment at six sites along the Oregon coast, I found that both regional and local dynamics constrain the recovery of communities after disturbance. Half of the time, the community returned to the state of the nearby community type. The remaining communities were influenced by priority effects that could be predicted based on 1) regional dynamics favoring some species over others, or 2) the timing of arrival of important facilitating species. Overall, understanding the dynamic relationship between the persistence of diverse communities and a changing environment remains one of the challenges of our time. My dissertation highlights some of the challenges in predicting the future composition of communities under climate change, but also provides some ways forward. Integration of experimental, theoretical, and observational studies builds the scaffolding of prediction, whereby understanding the constraints on species physiology, the interactions among species, and community assembly can help frame the context in which predictions are made. Title: Predictability and Constraints on the Structure of Ecological Communities in the Context of Climate Change Author: Barner, Allison K. Ecologists must increasingly balance the need for accurate predictions about how ecosystems will be affected by climate change, against the fact that making such predictions at the ecosystem-level may be infeasible. Although information about responses of individual species to a changing environment is increasing, scaling such information to the community level is challenging. To date, predicting responses of ecological communities to climate change is constrained by limited theoretical and empirical knowledge about the response of communities and ecosystems to change. My dissertation addresses several knowledge gaps in our understanding of community structure under climate change. This research draws from a rich experimental tradition in the species-diverse model ecosystem of the US Pacific Northwest rocky intertidal to test ecological theory. In Chapter 2, I assessed whether the response of multiple species of coralline algae to global change could be predicted from basic first principles of chemistry, physiology, and ecology. Given the rate of global change, and the time-consuming process of experimentally determining species responses to climate change, I hypothesized that species can be grouped using existing theory, either by their evolutionary relatedness or by their ecological traits, such that climate responses are similar within a group. Such a scheme would greatly reduce the number of experiments needed to characterize species climate vulnerability, requiring the characterization of the response of groups of species to climate change, rather than individual species. Using a suite of five co-occurring species of intertidal articulated coralline algae (Corallina vancouveriensis, Corallina officinalis, Bossiella plumosa, Bossiella orbiginiana, and Calliarthron tuberculosum), I applied this framework to generate ten mutually exclusive hypotheses that could explain organismal response to ocean acidification, a consequence of global climate change that threatens marine calcifying species. I found that all species had similar responses to ocean acidification, and that responses were generally predicted by the body size of the individual. Despite the power that such a framework provides in understanding group-level response to climate change, predicting community-level response requires knowledge of how organisms affect one another. In Chapter 3, I quantified species interactions in a series of removal experiments to estimate the reciprocal effects between a canopy-forming intertidal kelp (Saccharina sessilis) and a suite of understory species that persist beneath the kelp canopy. This experiment was replicated in different oceanographic conditions across a large latitudinal gradient, as a step towards understanding how interactions might change with climate change. However, the experiment demonstrated that interactions between the canopy and understory were consistent among different environmental conditions. Furthermore, the strongest effect was that of understory species, particularly articulated coralline turf algae, on the canopy species. The coralline turf algae both facilitated the recruitment of the canopy species and buffered the canopy from abiotic stress during its adult life stage. Combining experimental results and observational surveys, a hypothesized interaction network for these species was constructed, highlighting the importance of direct and indirect species interactions in promoting species coexistence. A long-standing controversy in ecology is whether or not species interactions can be inferred from observational data, as opposed to from experimental tests. Although the rocky intertidal ecosystem is unique for its ease of experimental manipulation, quantifying species interactions experimentally is often difficult or impossible. As an alternative, many have turned to statistical methods to estimate species interactions from observational data, namely, from patterns in species pairwise co-occurrences. In Chapter 4, I examined these co-occurrence methods and their potential relationship to experimentally measured species interactions. I first used a suite of different co-occurrence methods to generate a set of predicted species interactions of macrophytes and invertebrates from observational surveys conducted in the rocky intertidal zone of Oregon. I then compared the predicted species interactions to the same pairwise species interactions determined experimentally and assembled from the literature. Overall, of the seven methods tested, each generated a different set of predicted species interactions from the same data, and all methods predicted interactions that did not match those in the experimental database. Thus, predicting species interactions from patterns in occurrence remains elusive. Importantly, much work remains to be done to understand the link between species co-occurrences and their actual interactions with one another on the landscape. A key limiting frontier in climate change ecology is determining the influence of species interactions on species distributions across the landscape, and the sensitivity of such interactions to changes in climate. Finally, in Chapter 5, I used theory from the published literature and knowledge from my previous chapters to make predictions the recovery of low rocky intertidal communities after a disturbance. The process of community development after disturbance has been studied in many ways, from the successional studies of the early 1900s, to modern community assembly theory. In recent years, a focus on the unpredictability of community assembly has emerged, paying particular attention to the role of historical contingency, or priority effects, in determining the recovery trajectory of a community. Priority effects occur when the arrival of a species after a disturbance inalterably changes the composition of the developing community, driving the assembly of widely different communities at a small spatial scale. I conducted a community assembly experiment in three different low intertidal zone community "types", each characterized by different dominant macrophyte species (Saccharina sessilis, Phyllospadix spp., and algal "turfs"). Replicating this experiment at six sites along the Oregon coast, I found that both regional and local dynamics constrain the recovery of communities after disturbance. Half of the time, the community returned to the state of the nearby community type. The remaining communities were influenced by priority effects that could be predicted based on 1) regional dynamics favoring some species over others, or 2) the timing of arrival of important facilitating species. Overall, understanding the dynamic relationship between the persistence of diverse communities and a changing environment remains one of the challenges of our time. My dissertation highlights some of the challenges in predicting the future composition of communities under climate change, but also provides some ways forward. Integration of experimental, theoretical, and observational studies builds the scaffolding of prediction, whereby understanding the constraints on species physiology, the interactions among species, and community assembly can help frame the context in which predictions are made. Close

• 23. [Article] The ecological consequences of the reduction of species diversity : experimental approaches

  The influence of loss of diversity on community dynamics and ecosystem functioning has recently received considerable attention. Although study of biodiversity has a long history within ecology, empirical ...

  Citation × Citation Citation Abstract Copy Title: The ecological consequences of the reduction of species diversity : experimental approaches Author: Allison, Gary William The influence of loss of diversity on community dynamics and ecosystem functioning has recently received considerable attention. Although study of biodiversity has a long history within ecology, empirical investigations exploring consequences of loss have been rare. Because many factors confound diversity comparisons, experimental manipulations of diversity offer the most direct way of attributing cause to diversity loss. The effects of reduction in number of species will depend on the strength and sign of species interactions affected by loss of diversity. An experiment performed on a high zone, rocky intertidal community in which macroalgal diversity was manipulated demonstrated that effects of diversity loss will be highly dependent on which species are removed. However, effects of diversity reductions were strongest at the harsh end of a stress gradient where interactions were more positive. Thus, factors that affect the strength and sign of species interactions such as the degree of physical stress may serve as a rough guide to where the effects of diversity loss will be most severe. An assessment of the influence of diversity on community response to a strong physical perturbation was performed using an experimentally-induced thermal stress. Higher diversity treatments were most strongly affected directly by the stress because such treatments had higher abundance and therefore more biomass to lose. However, those same treatments recovered more quickly from the stress. Community recovery of initially low diversity treatments was slowed by persistence of non-typical states or slow recovery of dominant species. A simulation study was performed to assess the ability of different experimental designs to detect biodiversity effects. Our ability to predict consequences of changes in diversity will be dependent on our ability to distinguish the most influential biodiversity "components" within a system. This study uncovered a phenomenon that will be common in biodiversity studies: misidentification of one biodiversity component (e. g., an effect of a keystone species) as a different component (e. g., an effect of the number of species). I call this phenomenon "aliasing." Because of the complexity of biodiversity, experiments and observational studies will be highly susceptible to aliasing and, thus, results will require careful interpretation. Title: The ecological consequences of the reduction of species diversity : experimental approaches Author: Allison, Gary William The influence of loss of diversity on community dynamics and ecosystem functioning has recently received considerable attention. Although study of biodiversity has a long history within ecology, empirical investigations exploring consequences of loss have been rare. Because many factors confound diversity comparisons, experimental manipulations of diversity offer the most direct way of attributing cause to diversity loss. The effects of reduction in number of species will depend on the strength and sign of species interactions affected by loss of diversity. An experiment performed on a high zone, rocky intertidal community in which macroalgal diversity was manipulated demonstrated that effects of diversity loss will be highly dependent on which species are removed. However, effects of diversity reductions were strongest at the harsh end of a stress gradient where interactions were more positive. Thus, factors that affect the strength and sign of species interactions such as the degree of physical stress may serve as a rough guide to where the effects of diversity loss will be most severe. An assessment of the influence of diversity on community response to a strong physical perturbation was performed using an experimentally-induced thermal stress. Higher diversity treatments were most strongly affected directly by the stress because such treatments had higher abundance and therefore more biomass to lose. However, those same treatments recovered more quickly from the stress. Community recovery of initially low diversity treatments was slowed by persistence of non-typical states or slow recovery of dominant species. A simulation study was performed to assess the ability of different experimental designs to detect biodiversity effects. Our ability to predict consequences of changes in diversity will be dependent on our ability to distinguish the most influential biodiversity "components" within a system. This study uncovered a phenomenon that will be common in biodiversity studies: misidentification of one biodiversity component (e. g., an effect of a keystone species) as a different component (e. g., an effect of the number of species). I call this phenomenon "aliasing." Because of the complexity of biodiversity, experiments and observational studies will be highly susceptible to aliasing and, thus, results will require careful interpretation. Close

• 24. [Article] Fishermen, Markets, and Population Diversity

  Fishing impacts biodiversity on multiple levels, potentially resulting in unintended feedbacks to economic performance of the fishery over time. For example, targeting observable traits within a population ...

  Citation × Citation Citation Abstract Copy Title: Fishermen, Markets, and Population Diversity Author: Sanchirico, James N., Jardine, Sunny Fishing impacts biodiversity on multiple levels, potentially resulting in unintended feedbacks to economic performance of the fishery over time. For example, targeting observable traits within a population can impact genetic diversity, targeting populations within a species can impact population diversity, and targeting valuable species can impact biodiversity at the ecosystem level. The natural science and economics literatures, however, have given little attention to the impact of fishing on population diversity, even though population diversity is directly linked ecosystem services and estimates of population extinction rates are three orders of magnitude higher than species extinction rates. Here we develop a stochastic bioeconomic model that links the harvest of multiple salmon populations by a single commercial fishery to the trajectory of population diversity in a salmon stock complex. We parameterize our model with biological and economic data from the Copper River Chinook salmon fishery. We show that markets can incentivize the degradation of population diversity, reducing infra-marginal fishery rents and increase the variability in financial returns to the fishery. Factors impacting the magnitude of our results include the level and distribution of harvesting efficiency and market conditions. We also show that second-best management can conserve population diversity and improve welfare. Furthermore, depending fishermen’s time preferences, this management strategy is potentially self-financing. Title: Fishermen, Markets, and Population Diversity Author: Sanchirico, James N., Jardine, Sunny Fishing impacts biodiversity on multiple levels, potentially resulting in unintended feedbacks to economic performance of the fishery over time. For example, targeting observable traits within a population can impact genetic diversity, targeting populations within a species can impact population diversity, and targeting valuable species can impact biodiversity at the ecosystem level. The natural science and economics literatures, however, have given little attention to the impact of fishing on population diversity, even though population diversity is directly linked ecosystem services and estimates of population extinction rates are three orders of magnitude higher than species extinction rates. Here we develop a stochastic bioeconomic model that links the harvest of multiple salmon populations by a single commercial fishery to the trajectory of population diversity in a salmon stock complex. We parameterize our model with biological and economic data from the Copper River Chinook salmon fishery. We show that markets can incentivize the degradation of population diversity, reducing infra-marginal fishery rents and increase the variability in financial returns to the fishery. Factors impacting the magnitude of our results include the level and distribution of harvesting efficiency and market conditions. We also show that second-best management can conserve population diversity and improve welfare. Furthermore, depending fishermen’s time preferences, this management strategy is potentially self-financing. Close

• 25. [Article] Native bee diversity and floral resource availability in two Willamette Valley Oregon ecosystems

  The importance of pollinators in native and managed landscapes is well known, and recent interest is directed towards investigating the role of native bees as providers of pollination ecosystem services. ...

  Citation × Citation Citation Abstract Copy Title: Native bee diversity and floral resource availability in two Willamette Valley Oregon ecosystems Author: Bergh, Jennifer E. The importance of pollinators in native and managed landscapes is well known, and recent interest is directed towards investigating the role of native bees as providers of pollination ecosystem services. Uncertainty about bee populations at global and local scales has prompted research and general interest in conservation of bee diversity. To sustain robust populations, bees need nesting habitat and quality forage resources. This thesis describes two studies related to the relationship between bee diversity and landscape floral resource availability in two Willamette Valley ecosystems: wet prairies and blueberry agroecosystems. The wetlands are florally diverse, heterogeneous, and temporally patchy in spring and summer, whereas blueberries are florally abundant during spring crop bloom with potentially fewer floral resources after berry set; the intention of these studies was to determine if the floral resources in each ecosystem were adequate to support robust native bee communities. For each site type, the bee fauna and associated melittophilous floral resources are described and characterized. In the studies, it was determined that bee diversity, and specifically bee abundance, was positively correlated with floral resources. This thesis presents the results of community analyses, floral resources that were identified as important forage sources, and a discussion of the relationship between landscape phenology and bee population dynamics in each ecosystem type. Implications and recommendations for landscape management to conserve and potentially enhance local native bee communities are discussed. Title: Native bee diversity and floral resource availability in two Willamette Valley Oregon ecosystems Author: Bergh, Jennifer E. The importance of pollinators in native and managed landscapes is well known, and recent interest is directed towards investigating the role of native bees as providers of pollination ecosystem services. Uncertainty about bee populations at global and local scales has prompted research and general interest in conservation of bee diversity. To sustain robust populations, bees need nesting habitat and quality forage resources. This thesis describes two studies related to the relationship between bee diversity and landscape floral resource availability in two Willamette Valley ecosystems: wet prairies and blueberry agroecosystems. The wetlands are florally diverse, heterogeneous, and temporally patchy in spring and summer, whereas blueberries are florally abundant during spring crop bloom with potentially fewer floral resources after berry set; the intention of these studies was to determine if the floral resources in each ecosystem were adequate to support robust native bee communities. For each site type, the bee fauna and associated melittophilous floral resources are described and characterized. In the studies, it was determined that bee diversity, and specifically bee abundance, was positively correlated with floral resources. This thesis presents the results of community analyses, floral resources that were identified as important forage sources, and a discussion of the relationship between landscape phenology and bee population dynamics in each ecosystem type. Implications and recommendations for landscape management to conserve and potentially enhance local native bee communities are discussed. Close

• 26. [Article] Evaluating tradeoffs among ecosystem services to inform marine spatial planning

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/marine-policy/.

  Citation × Citation Citation Abstract Copy Title: Evaluating tradeoffs among ecosystem services to inform marine spatial planning Author: Gaines, Steven D., Halpern, Benjamin S., Lester, Sarah E., Barth, John A., White, Crow, Costello, Christopher This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/marine-policy/. Title: Evaluating tradeoffs among ecosystem services to inform marine spatial planning Author: Gaines, Steven D., Halpern, Benjamin S., Lester, Sarah E., Barth, John A., White, Crow, Costello, Christopher This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/marine-policy/. Close

• 27. [Article] Cultural Biodiversity: Indigenous Relationships within Their Environment

  When we talk about indigenous cultural practices we are in fact talking about responsibilities that have evolved into unwritten tribal laws over millennia. These responsibilities and laws are directly ...

  Citation × Citation Citation Abstract Copy Title: Cultural Biodiversity: Indigenous Relationships within Their Environment Author: Happynook, Tom Mexsis Year: 2001 When we talk about indigenous cultural practices we are in fact talking about responsibilities that have evolved into unwritten tribal laws over millennia. These responsibilities and laws are directly tied to nature and is a product of the slow integration of cultures within their environment and the ecosystems. Thus, the environment is not a place of divisions but rather a place of relations, a place where cultural diversity and bio-diversity are not separate but in fact need each other. The most important aspects of cultural bio-diversity are those that integrate people, (the human relationship), with the ecosystems found within their environment. Some indigenous practices had cultural importance at the time they were being practiced, (arranged marriages, etc), but most indigenous practices, such as fishing, hunting and gathering have a much deeper ecological management role. These indigenous practices maintained the balance within nature, the environment and the ecosystems. I am not talking about the morality of the cultural practice, but rather the cultural practice of responsibility to bio-diversity. It is from this perspective that we begin to realize that the realm of cultural diversity and bio-diversity are not separate from the environment but rather connected through our relationships with the ecosystems. This is cultural biodiversity; a practice which has been developed and nurtured over millennia; in the Nuu-chah-nulth language “Hishuk Tsawalk”, everything is one, everything is connected. In today’s world, laws have been created around “the human relationship aspect”. Unfortunately, these laws have established a system that leaves humans outside of nature or makes us believe that we are dominant over the environment or a cancer on this earth. We have even created a set of consequences for any broken human relations within this system: fines, prisons, institutions, etc. On the other hand, indigenous peoples have lived within the “law of nature”. It is within this boundary that our indigenous systems of justice, tribal laws, societies and cultural practices developed and have turned into the indigenous rights of today. Title: Cultural Biodiversity: Indigenous Relationships within Their Environment Author: Happynook, Tom Mexsis Year: 2001 When we talk about indigenous cultural practices we are in fact talking about responsibilities that have evolved into unwritten tribal laws over millennia. These responsibilities and laws are directly tied to nature and is a product of the slow integration of cultures within their environment and the ecosystems. Thus, the environment is not a place of divisions but rather a place of relations, a place where cultural diversity and bio-diversity are not separate but in fact need each other. The most important aspects of cultural bio-diversity are those that integrate people, (the human relationship), with the ecosystems found within their environment. Some indigenous practices had cultural importance at the time they were being practiced, (arranged marriages, etc), but most indigenous practices, such as fishing, hunting and gathering have a much deeper ecological management role. These indigenous practices maintained the balance within nature, the environment and the ecosystems. I am not talking about the morality of the cultural practice, but rather the cultural practice of responsibility to bio-diversity. It is from this perspective that we begin to realize that the realm of cultural diversity and bio-diversity are not separate from the environment but rather connected through our relationships with the ecosystems. This is cultural biodiversity; a practice which has been developed and nurtured over millennia; in the Nuu-chah-nulth language “Hishuk Tsawalk”, everything is one, everything is connected. In today’s world, laws have been created around “the human relationship aspect”. Unfortunately, these laws have established a system that leaves humans outside of nature or makes us believe that we are dominant over the environment or a cancer on this earth. We have even created a set of consequences for any broken human relations within this system: fines, prisons, institutions, etc. On the other hand, indigenous peoples have lived within the “law of nature”. It is within this boundary that our indigenous systems of justice, tribal laws, societies and cultural practices developed and have turned into the indigenous rights of today. Close

• 28. [Article] Forecasting functional implications of global changes in riparian plant communities

  This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://esa.org/.

  Citation × Citation Citation Abstract Copy Title: Forecasting functional implications of global changes in riparian plant communities Author: Mineau, Madeleine M., McElarney, Yvonne R., Fischer, Dylan G., Tiegs, Scott D., Canhoto, Cristina, Larranaga, Aitor, Giling, Darren P., Swan, Christopher M., Kominoski, John S., LeRoy, Carri J., Gonzalez, Eduardo, Griffiths, Natalie A., Shirley, Susan M., Follstad Shah, Jennifer J. This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://esa.org/. Title: Forecasting functional implications of global changes in riparian plant communities Author: Mineau, Madeleine M., McElarney, Yvonne R., Fischer, Dylan G., Tiegs, Scott D., Canhoto, Cristina, Larranaga, Aitor, Giling, Darren P., Swan, Christopher M., Kominoski, John S., LeRoy, Carri J., Gonzalez, Eduardo, Griffiths, Natalie A., Shirley, Susan M., Follstad Shah, Jennifer J. This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://esa.org/. Close

• 29. [Article] The Human Side of the Ecosystem Approach to Fisheries Management: Preliminary Results of an FAO Expert Consultation

  Research Paper

  Citation × Citation Citation Abstract Copy Title: The Human Side of the Ecosystem Approach to Fisheries Management: Preliminary Results of an FAO Expert Consultation Author: De Young, Cassandra Research Paper Title: The Human Side of the Ecosystem Approach to Fisheries Management: Preliminary Results of an FAO Expert Consultation Author: De Young, Cassandra Research Paper Close

• 30. [Article] Convergent diversity and trait composition in temporary streams and ponds

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Ecological Society of America. The published article can be found at: http://esajournals.online...

  Citation × Citation Citation Abstract Copy Title: Convergent diversity and trait composition in temporary streams and ponds Author: Lytle, David A., Schriever, Tiffany A. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Ecological Society of America. The published article can be found at: http://esajournals.onlinelibrary.wiley.com/hub/journal/10.1002/%28ISSN%292150-8925/ Title: Convergent diversity and trait composition in temporary streams and ponds Author: Lytle, David A., Schriever, Tiffany A. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Ecological Society of America. The published article can be found at: http://esajournals.onlinelibrary.wiley.com/hub/journal/10.1002/%28ISSN%292150-8925/ Close