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• 1. [Article] The Value and Propriety of Reintroduction as a Conservation Tool for Rare Plants

  Three recent reviews of reintroduction for conservation purposes, which draw on substantial and largely non-overlapping data sets, have come to strikingly different conclusions about its value. One concludes ...

  Citation × Citation Citation Abstract Copy Title: The Value and Propriety of Reintroduction as a Conservation Tool for Rare Plants Author: Guerrant, Edward O., Jr. Year: 2013 Three recent reviews of reintroduction for conservation purposes, which draw on substantial and largely non-overlapping data sets, have come to strikingly different conclusions about its value. One concludes that “reintroduction is generally unlikely to be a successful conservation strategy as currently conducted.” Another that “…this review cannot conclusively comment on the effectiveness of re-introductions…” The third concludes there is “strong evidence in support of the notion that reintroduction, especially in combination with ex situ conservation, is a tool that can go a long way toward meeting the needs it was intended to address.” The argument over the conservation value of reintroduction is of more than academic interest. It illustrates a challenge facing land managers and decision makers who may be tempted to act on stated conclusions without thoroughly understanding their underlying assumptions, methodology and terminology. The differing conclusions can be partially explained by different criteria of what constitutes success, how to measure it, and differing time scales considered. The propriety of reintroduction is briefly discussed and focuses on two issues: translocation of naturally occurring individuals to new locations, and introduction outside a species’ naturally occurring range. Both have appropriate uses, but can be used in ways that detract from the survival prospects of taxa. Title: The Value and Propriety of Reintroduction as a Conservation Tool for Rare Plants Author: Guerrant, Edward O., Jr. Year: 2013 Three recent reviews of reintroduction for conservation purposes, which draw on substantial and largely non-overlapping data sets, have come to strikingly different conclusions about its value. One concludes that “reintroduction is generally unlikely to be a successful conservation strategy as currently conducted.” Another that “…this review cannot conclusively comment on the effectiveness of re-introductions…” The third concludes there is “strong evidence in support of the notion that reintroduction, especially in combination with ex situ conservation, is a tool that can go a long way toward meeting the needs it was intended to address.” The argument over the conservation value of reintroduction is of more than academic interest. It illustrates a challenge facing land managers and decision makers who may be tempted to act on stated conclusions without thoroughly understanding their underlying assumptions, methodology and terminology. The differing conclusions can be partially explained by different criteria of what constitutes success, how to measure it, and differing time scales considered. The propriety of reintroduction is briefly discussed and focuses on two issues: translocation of naturally occurring individuals to new locations, and introduction outside a species’ naturally occurring range. Both have appropriate uses, but can be used in ways that detract from the survival prospects of taxa. Close

• 2. [Article] Sampling for Effective Ex Situ Plant Conservation

  Sampling a whole flora or any significant subset for ex situ conservation purposes is a complex, long-term proposition. Thus, it is important to consider what constitutes an adequate sample not only for ...

  Citation × Citation Citation Abstract Copy Title: Sampling for Effective Ex Situ Plant Conservation Author: Guerrant, Edward O., Jr., Havens, Kayri, Vitt, Pati Year: 2014 Sampling a whole flora or any significant subset for ex situ conservation purposes is a complex, long-term proposition. Thus, it is important to consider what constitutes an adequate sample not only for all taxa as a whole but also for each taxon individually as well as how to strategically schedule collection over time. There are five basic sampling questions: from which species to collect, from how many and which populations, from how many and which individuals, how many and what kind of propagules to collect, and, finally, at what point is the desired sample size too great for a population to bear in one year? There is no single correct sampling strategy or protocol. Each situation must be evaluated in the context of the particular purposes, goals, and uses for which the collection is being made as well as the nature of the sampling universe, the manner in which the samples will be stored and maintained, the period of time they will be stored, and whether the wild-collected samples are to be used directly or whether their numbers will be increased by agricultural growouts. Purposes include providing a long-term “insurance policy” against extinction in the wild and, in the near to medium term, supplying native plant material for small- to large-scale restoration purposes. The term “sampling universe” refers to the target taxa of interest: it could be the entire seed plant flora of Taiwan or particular subsets, such as endemics, higher-elevation plants, ecologically important taxa, rare plants, and so on. Plants with orthodox seeds are much easier to work with and are more economically stored as dried, frozen seeds in a seed bank than either plants with recalcitrant seeds or taxa maintained as growing plants. Title: Sampling for Effective Ex Situ Plant Conservation Author: Guerrant, Edward O., Jr., Havens, Kayri, Vitt, Pati Year: 2014 Sampling a whole flora or any significant subset for ex situ conservation purposes is a complex, long-term proposition. Thus, it is important to consider what constitutes an adequate sample not only for all taxa as a whole but also for each taxon individually as well as how to strategically schedule collection over time. There are five basic sampling questions: from which species to collect, from how many and which populations, from how many and which individuals, how many and what kind of propagules to collect, and, finally, at what point is the desired sample size too great for a population to bear in one year? There is no single correct sampling strategy or protocol. Each situation must be evaluated in the context of the particular purposes, goals, and uses for which the collection is being made as well as the nature of the sampling universe, the manner in which the samples will be stored and maintained, the period of time they will be stored, and whether the wild-collected samples are to be used directly or whether their numbers will be increased by agricultural growouts. Purposes include providing a long-term “insurance policy” against extinction in the wild and, in the near to medium term, supplying native plant material for small- to large-scale restoration purposes. The term “sampling universe” refers to the target taxa of interest: it could be the entire seed plant flora of Taiwan or particular subsets, such as endemics, higher-elevation plants, ecologically important taxa, rare plants, and so on. Plants with orthodox seeds are much easier to work with and are more economically stored as dried, frozen seeds in a seed bank than either plants with recalcitrant seeds or taxa maintained as growing plants. Close

• 3. [Article] Fire Modulates Climate Change Response of Simulated Aspen Distribution Across Topoclimatic Gradients in a Semi-Arid Montane Landscape

  Content Changing aspen distribution in response to climate change and fire is a major focus of biodiversity conservation, yet little is known about the potential response of aspen to these two driving ...

  Citation × Citation Citation Abstract Copy Title: Fire Modulates Climate Change Response of Simulated Aspen Distribution Across Topoclimatic Gradients in a Semi-Arid Montane Landscape Author: Yang, Jian, Weisberg, Peter J., Shinneman, Douglas J., Dilts, Thomas E., Earnst, Susan L., Scheller, Robert M. Year: 2015 Content Changing aspen distribution in response to climate change and fire is a major focus of biodiversity conservation, yet little is known about the potential response of aspen to these two driving forces along topoclimatic gradients. Objective This study is set to evaluate how aspen distribution might shift in response to different climate-fire scenarios in a semi-arid montane landscape, and quantify the influence of fire regime along topoclimatic gradients. Methods We used a novel integration of a forest landscape succession and disturbance model (LAN DIS-II) with a fine-scale climatic water deficit approach to simulate dynamics of aspen and associated conifer and shrub species over the next 150 years under various climate-fire scenarios. Results Simulations suggest that many aspen stands could persist without fire for centuries under current climate conditions. However, a simulated 2–5ºC increase in temperature caused a substantial reduction of aspen coverage at lower elevations and a modest increase at upper elevations, leading to an overall reduction of aspen range at the landscape level. Increasing fire activity may favor aspen increase at its upper elevation limits adjacent to coniferous forest, but may also favor reduction of aspen at lower elevation limits adjacent to xeric shrubland. Conclusions Our study highlights the importance of incorporating fine-scale terrain effects on climatic water deficit and ecohydrology when modeling species distribution response to climate change. This modeling study suggests that climate mitigation and adaptation strategies that use fire would benefit from consideration of spatial context at landscape scales. Title: Fire Modulates Climate Change Response of Simulated Aspen Distribution Across Topoclimatic Gradients in a Semi-Arid Montane Landscape Author: Yang, Jian, Weisberg, Peter J., Shinneman, Douglas J., Dilts, Thomas E., Earnst, Susan L., Scheller, Robert M. Year: 2015 Content Changing aspen distribution in response to climate change and fire is a major focus of biodiversity conservation, yet little is known about the potential response of aspen to these two driving forces along topoclimatic gradients. Objective This study is set to evaluate how aspen distribution might shift in response to different climate-fire scenarios in a semi-arid montane landscape, and quantify the influence of fire regime along topoclimatic gradients. Methods We used a novel integration of a forest landscape succession and disturbance model (LAN DIS-II) with a fine-scale climatic water deficit approach to simulate dynamics of aspen and associated conifer and shrub species over the next 150 years under various climate-fire scenarios. Results Simulations suggest that many aspen stands could persist without fire for centuries under current climate conditions. However, a simulated 2–5ºC increase in temperature caused a substantial reduction of aspen coverage at lower elevations and a modest increase at upper elevations, leading to an overall reduction of aspen range at the landscape level. Increasing fire activity may favor aspen increase at its upper elevation limits adjacent to coniferous forest, but may also favor reduction of aspen at lower elevation limits adjacent to xeric shrubland. Conclusions Our study highlights the importance of incorporating fine-scale terrain effects on climatic water deficit and ecohydrology when modeling species distribution response to climate change. This modeling study suggests that climate mitigation and adaptation strategies that use fire would benefit from consideration of spatial context at landscape scales. Close