Author ORCID Identifier

https://orcid.org/0000-0002-6193-0207

Year of Publication

2020

Degree Name

Doctor of Philosophy (PhD)

Document Type

Doctoral Dissertation

College

Arts and Sciences

Department

Biology

First Advisor

Dr. David Weisrock

Second Advisor

Dr. John Cox

Abstract

Understanding the link between landscape patterns and ecological and evolutionary processes is an important prerequisite for informed wildlife conservation and management, especially in rapidly changing landscapes. Until recently, the inaccessibility of spatial and genomic data sets of sufficient resolution limited our ability to incorporate the impacts of landscape patterns into predictions of ecological and environmental outcomes. In this dissertation, I utilized several high-resolution spatial and genomic data sets to address ecological questions in a rapidly fragmenting landscape in southeastern Kentucky. Overall, my results indicate that large-scale surface coal mining is causing widespread homogenization of landforms, resulting in a uniquely permanent form of habitat loss. This is likely causing significant fragmentation of remain forested habitat in many portions of the Cumberland Plateau of Kentucky, as evidenced by reductions in suitable overwintering habitat for the timber rattlesnake (Crotalus horridus). At the level of the individual, the high resolution and three-dimensional imagery provided by lidar remote sensing systems allows for a much more accurate assessment of the drivers of individual movement in C. horridus than using coarse topographic data sets alone. While this fragmentation might be expected to limit migration and increase genetic differentiation among population, patterns of genomic diversity in another common pit viper, the copperhead (Agkistrodon contortrix), suggest that contemporary surface mining is not associated with spatial patterns of genomic diversity. However, using a 2,140 SNP data set, I did find significant associations between a historic highway path and divergent genomic patterns, suggesting a time lag may be responsible for contemporary genomic patterns associated with a historic barrier to movement. When examining the landscape at broad spatial scales, the topographic rearrangement of land after mining followed steady patterns until approximately 2011. At this point, coinciding with federal policy shifts aimed at reducing the frequency of valley fill operations, mining impacts in stream bottoms decreased markedly, but ridgetops and upper slopes continued to be impacted at rates equal to or greater than before 2011. I recommend topographic restoration be highlighted as a worthy goal of reclamation, on par with vegetation establishment and erosion control.

Digital Object Identifier (DOI)

https://doi.org/10.13023/etd.2020.242

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