RESTORING PLANT COMMUNITIES FOR MULTIPLE ECOSYSTEM FUNCTIONS AFTER NATURAL RESOURCE DEVELOPMENT
Open Access
- Author:
- Barlow, Kathryn Marie
- Graduate Program:
- Ecology
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- December 05, 2018
- Committee Members:
- David A. Mortensen, Dissertation Advisor/Co-Advisor
David A. Mortensen, Committee Chair/Co-Chair
Patrick J. Drohan, Committee Member
Katriona Shea, Committee Member
Richard M. Doyle, Outside Member - Keywords:
- ecological restoration
unconventional gas
invasive plants
native seed mixes
environmental regulations - Abstract:
- Natural resource development is a significant contributor to terrestrial conversion globally. The ecosystem functions and services that are degraded or lost to extraction activities must be restored after development to regain ecological integrity in the surrounding landscape. Restoration of such highly disturbed ecosystems has historically been reactive, not proactive, and limited to site stabilization measures to control soil erosion. In addition to site stabilization, restoration must also prioritize setting the successional trajectory for plant communities that will provide for multiple ecosystem functions over time. The development of oil and gas reservoirs with low permeability and porosity, commonly referred to as unconventional production, has only become economically feasible in the last decade. Thus far, most measures to regulate and restore the terrestrial footprint of unconventional gas development in the Marcellus and Utica Shales in the northeastern United States have been reactive and limited in scope. Here, we aim to bring attention to the limited nature of the restoration approach and governing regulations, and offer alternatives from the perspective of restoration ecology. In Chapter Two, we report on the main drivers contributing to the spread of invasive plants along shale gas infrastructure, documenting the shift in plant community composition from a largely native forest to incursions of non-native plants. In Chapter Three, we provide an assessment of the establishment success of a native perennial plant mixture on compacted soils, typical conditions of shale gas well pads, as an alternative to the widespread use of non-native, cool season grasses and legumes. In Chapter Four, we report on a floristic survey of a gas pipeline corridor seeded with a similar native perennial mixture to assess the long-term assembly of these species across an environmental gradient. Finally, to address the limited scope of reclamation regulations we outline specific language and concepts in regulations pertaining to the “earth disturbance activities” of shale gas that are barriers to shifting the norms of reclamation to ecological restoration. This research highlights vegetation changes within the footprint of shale gas production. Non-native plants are recruited inadvertently via the high level of anthropogenic activities on drilling sites, and directly from restoration seed mixes. We demonstrate the potential for using native plants for restoration to set the successional trajectory for restoring multiple ecosystem functions beyond erosion control. However, restoration practices are unlikely to change at a scale that matters unless regulations address the lost value of terrestrial ecosystems.