Date of Award
Winter 2024
Project Type
Dissertation
Program or Major
Earth and Environmental Sciences
Degree Name
Doctor of Philosophy
First Advisor
Michael W. Palace
Second Advisor
Mark G. Anderson
Third Advisor
Catherine M. Ashcraft
Abstract
As the climate changes, species must either adapt, relocate, or face extinction. This pressing reality underscores the importance of promoting climate connectivity, which ensures that habitats and landscapes remain interconnected, allowing species to move and adapt as climate conditions shift. Given the challenges posed by ongoing climate change, it is crucial that land conservation decisions incorporate climate connectivity. Conservation goals should be informed by the latest connectivity models and be practical for implementation by on-the-ground practitioners. This dissertation aims to bridge the gap between these two critical needs, which are not always well-integrated in conservation work. Modeling connectivity in a changing climate often requires significant computational effort and specialized programming skills, which may not be readily accessible to conservation practitioners. Additionally, the decisions made by scientists and modelers are not always informed by the practical knowledge of conservation practitioners. In this dissertation, I seek to connect on-the-ground practitioners with cutting-edge connectivity modeling to enable strategic and effective conservation decisions. My research question is “How can climate connectivity be incorporated into land conservation decisions?” I provide background and introduce this question in Chapter One. In Chapter Two I develop, validate, and assess progress on a national map of connectivity and climate flow for land conservation. I find that 44% of the continental United States is in areas of connectivity and climate flow. These areas are critical for species dispersal and migration, identifying regions of diffuse and concentrated flow as well as areas of low/blocked flow. Validation comparing dispersal, tree growth, and mortality in areas of climate flow and low/blocked flow in the U.S. Forest Service’s Forest Inventory and Analysis (FIA) data for 24 tree species revealed mixed results, with some species showing significant correlations between climate flow areas and tree establishment, mortality, and growth. Chapter Two also assessed progress towards national and international conservation goals, finding that 44% of identified climate flow areas are currently protected, with significant gaps in protection for concentrated flow areas. The findings underscore the need for strategic conservation efforts to enhance landscape connectivity and support biodiversity in the face of climate change. Then in Chapter Three, I build off the methods in the connectivity and climate flow map to develop a method for modeling restoration of connectivity in heavily modified landscapes. In three high-ranking study areas within the Appalachians, I demonstrate a circuit-theory based approach simulating the connectivity value of restoring natural vegetation at sites with high human modification. I develop guidance and present a best practice on how to parameterize water in resistance grids to produce connectivity maps without artifacts of water in Chapter Four. In this chapter, I demonstrate water parameterization has important impacts on the outputs of terrestrial structural connectivity models that can complicate model interpretation. When the modeler’s intent is to inform land protection or restoration actions in response to human modification, assigning random resistance values for water minimizes the interaction between water and land pixels, clarifying output interpretation and use. Finally, in Chapter Five I present how this body of work was designed in a collaborative process and reflect on three key factors, defining the question, right people at the right time, and sharing and disseminating the results, that influenced the collaborative process and discuss successes and failures. Spanning the concerns and goals of NGOs, governments, local stakeholders, and connectivity conservation, this work will help inform the promises and challenges of moving conservation forward in new ways better aligned with our current climate emergency.
Recommended Citation
Clark, Melissa M., "Connecting Conservation: Modeling and Socializing Climate Connectivity for Land Conservation" (2024). Doctoral Dissertations. 2891.
https://scholars.unh.edu/dissertation/2891