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You searched for subject:(assisted colonization). Showing records 1 – 3 of 3 total matches.

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University of Toronto

1. Wadgymar, Susana Maria. Climate Change and Reproductive Phenology: Context-dependent Responses to Increases in Temperature and Implications for Assisted Colonization.

Degree: PhD, 2015, University of Toronto

Contemporary changes in climate have rapidly increased temperatures worldwide, extending the length of the growing season and eliciting large shifts in reproductive and growth traits across a diversity of plant taxa. The role of phenotypic plasticity in alleviating immediate changes in selection pressures must be thoroughly explored in order to identify the circumstances under which the survival of particular species may require active management. The major goals of my thesis were to characterize the contexts in which responses to warming occur and are adaptive, and to provide insight on the feasibility of assisted colonization (the movement of species beyond their current range boundary to climatically favorable habitat) and assisted gene flow (the relocation of multiple, genetically distinct populations to facilitate local adaptation). Focusing on the annual legume, Chamaecrista fasciculata, I applied artificial warming to simple plant communities to mimic the thermal regimes expected by the mid-21st century. Among experiments, I manipulated aspects of the abiotic and biotic environment likely to contribute to variation in plastic responses to warming, including plant genotype, community diversity, population density, internal patterns of resource allocation, and the frequency of rainfall. Reproductive phenological traits varied in their degree of response to warming, and photoperiodic constraints prevented optimal responses in populations of C. fasciculata from lower latitudes. In all cases, temperature-induced phenotypic plasticity was adaptive or neutral, but only sufficiently alleviated selection pressures in particular situations. Variation in competitive dynamics, pollinator access, and rainfall frequency did not modify responses to changes in temperature. This work identified barriers to assisted colonization across latitudes that arise when reproductive phenology is dependent on photoperiodic cues. Phenotypic plasticity may ameliorate some of the negative effects of increases in temperature, but persistent, directional selection pressures will require the evolution of life history traits for adaptation to climate change. Advisors/Committee Members: Weis, Arthur E, Ecology and Evolutionary Biology.

Subjects/Keywords: assisted colonization; climate change; natural selection; phenology; plasticity; 0329

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Wadgymar, S. M. (2015). Climate Change and Reproductive Phenology: Context-dependent Responses to Increases in Temperature and Implications for Assisted Colonization. (Doctoral Dissertation). University of Toronto. Retrieved from http://hdl.handle.net/1807/71400

Chicago Manual of Style (16th Edition):

Wadgymar, Susana Maria. “Climate Change and Reproductive Phenology: Context-dependent Responses to Increases in Temperature and Implications for Assisted Colonization.” 2015. Doctoral Dissertation, University of Toronto. Accessed October 23, 2020. http://hdl.handle.net/1807/71400.

MLA Handbook (7th Edition):

Wadgymar, Susana Maria. “Climate Change and Reproductive Phenology: Context-dependent Responses to Increases in Temperature and Implications for Assisted Colonization.” 2015. Web. 23 Oct 2020.

Vancouver:

Wadgymar SM. Climate Change and Reproductive Phenology: Context-dependent Responses to Increases in Temperature and Implications for Assisted Colonization. [Internet] [Doctoral dissertation]. University of Toronto; 2015. [cited 2020 Oct 23]. Available from: http://hdl.handle.net/1807/71400.

Council of Science Editors:

Wadgymar SM. Climate Change and Reproductive Phenology: Context-dependent Responses to Increases in Temperature and Implications for Assisted Colonization. [Doctoral Dissertation]. University of Toronto; 2015. Available from: http://hdl.handle.net/1807/71400


University of California – Santa Cruz

2. Skikne, Sarah. Using historic and contemporary data to inform conservation responses to climate change.

Degree: Environmental Studies, 2018, University of California – Santa Cruz

In the face of inevitable and increasing impacts of climate change, the conservation field must adapt its practices. To address this need, my dissertation utilizes untapped historic and contemporary data as empirical evidence to understand climate impacts and potential conservation responses. In my first chapter, I examine the demographic processes underlying range shifts in a California desert ecosystem, using re-photography and unique data extraction methods to track the fate of individual plants over ~35 years. I document uphill range shifts and demonstrate that varying recruitment and survival underlie these patterns in co-occurring species. In my second chapter, I synthesize data from historic avian translocations to uncover lessons relevant to proposals for longer-distance translocations and assisted colonization as potential adaptation tools. I find that post-translocation survival is higher for species with larger body sizes and brain residuals, and for translocations over shorter distances; these results suggest the types of species and sites that might be most feasible for translocation efforts in response to climate change. Finally, in my third chapter, I assess adaptation project proposals from U.S. conservation non-profits in order to determine gaps and strengths in this emerging field. I find that proposed projects are focused on fish, river ecosystems, and the Atlantic and Pacific coasts, highlighting the need for expansion of the current taxonomic, ecosystem and geographic foci of emerging climate adaptation efforts. Together, these chapters demonstrate the use of historic and contemporary data as fruitful paths for informing our response to climate change in order to promote species persistence and ecosystem integrity.

Subjects/Keywords: Conservation biology; Climate change; Ecology; assisted colonization; climate adaptation; global warming; range shifts; rephotography; translocation

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Skikne, S. (2018). Using historic and contemporary data to inform conservation responses to climate change. (Thesis). University of California – Santa Cruz. Retrieved from http://www.escholarship.org/uc/item/2bz0z83b

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Skikne, Sarah. “Using historic and contemporary data to inform conservation responses to climate change.” 2018. Thesis, University of California – Santa Cruz. Accessed October 23, 2020. http://www.escholarship.org/uc/item/2bz0z83b.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Skikne, Sarah. “Using historic and contemporary data to inform conservation responses to climate change.” 2018. Web. 23 Oct 2020.

Vancouver:

Skikne S. Using historic and contemporary data to inform conservation responses to climate change. [Internet] [Thesis]. University of California – Santa Cruz; 2018. [cited 2020 Oct 23]. Available from: http://www.escholarship.org/uc/item/2bz0z83b.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Skikne S. Using historic and contemporary data to inform conservation responses to climate change. [Thesis]. University of California – Santa Cruz; 2018. Available from: http://www.escholarship.org/uc/item/2bz0z83b

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

3. Chagnon Fontaine, Lysiane. The right tree at the right place: Exploring urban foresters' perceptions of assisted colonization.

Degree: 2014, University of Waterloo

Urban forests feature harsh growing conditions for trees. Urban trees are surrounded by heavy anthropogenic disturbances, they often have low genetic diversity, and it is difficult for managers to maintain them because of the fragmented ownership within cities. Climate change is now expected to worsen current ecological stressors. Extreme weather events, as well as pest and disease outbreaks, will likely become more frequent, and as the climate becomes warmer, populations and species will see their habitat shift to the north. Trees are long-lived species, and their ability to adapt or migrate can be challenged by rapid climate change. To sustain ecosystem services and forest biodiversity, and to rescue vulnerable species, urban foresters might resort to assisted colonization. With this strategy, species or populations are moved northward so they can establish in their new suitable climate. Assisted colonization is controversial because it entails many ecological risks and uncertainties, and appears to go against traditional conservation values of nature restoration and preservation. This thesis seeks to address a gap in our understanding of the perspectives and attitudes of urban foresters towards assisted colonization and related climate change adaptation strategies. I conducted semi-structured, open-ended interviews with 18 urban foresters from various forestry-related organizations in southern Ontario. I used a grounded approach for coding, letting the data guide the themes and codes rather than using predetermined ones. After going through my data a few times and developing codes, I then let concepts from the literature guide my coding to further refine the codes. I found that while urban foresters are generally open to constrained use of assisted colonization, it is not officially part of their ongoing management strategies. Respondents believe there need to be tree species trials and experiments, as well as comprehensive inventories and monitoring of the urban forest, but few were engaged in such programs. The findings show that ongoing efforts of such programs are small-scale and scattered across municipalities and organizations. I also found that respondents were planting southern tree species at the northern edge of their range, unknowingly implementing assisted population expansion, a variant of assisted colonization. For plantings in naturalized areas, respondents still strongly prioritize native species in their selection. In the short term, this suggests that assisted colonization is more likely to be used as a means to provide ecosystem services when native species fail to fulfill this role. Going forward with assisted migration will require increased community involvement and partnerships, and the fragmented ownership that characterizes urban forests might complicate assisted colonization initiatives. To overcome the prevailing uncertainties that act as an impediment to the implementation of assisted colonization, higher levels of governance will have to provide leadership and guidance.…

Subjects/Keywords: Assisted colonization; climate change; adaptation strategies; urban forestry

…summary of the state of assisted colonization in the urban forest sector of south Ontario x… …their northward movement if they are at risk. Assisted colonization is an adaptation2 strategy… …refer to assisted colonization as a potential strategy to assist the migration of trees (… …assisted colonization should not be seen as a cure-all to help forests adapt to climate change… …x29;. Ecological risks and uncertainties have made assisted colonization a strategy that has… 

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Chagnon Fontaine, L. (2014). The right tree at the right place: Exploring urban foresters' perceptions of assisted colonization. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/8864

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Chagnon Fontaine, Lysiane. “The right tree at the right place: Exploring urban foresters' perceptions of assisted colonization.” 2014. Thesis, University of Waterloo. Accessed October 23, 2020. http://hdl.handle.net/10012/8864.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Chagnon Fontaine, Lysiane. “The right tree at the right place: Exploring urban foresters' perceptions of assisted colonization.” 2014. Web. 23 Oct 2020.

Vancouver:

Chagnon Fontaine L. The right tree at the right place: Exploring urban foresters' perceptions of assisted colonization. [Internet] [Thesis]. University of Waterloo; 2014. [cited 2020 Oct 23]. Available from: http://hdl.handle.net/10012/8864.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Chagnon Fontaine L. The right tree at the right place: Exploring urban foresters' perceptions of assisted colonization. [Thesis]. University of Waterloo; 2014. Available from: http://hdl.handle.net/10012/8864

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

.