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Different Legacies, Similar Journeys: How Factors Within and Outside Management Control Structure Prairie Restorations and Remnants
Abstract
Ecological restoration can counter biodiversity collapse and create desired positive feedbacks, i.e., native plant restoration that attracts native fauna and supports ecological function. Habitat management is critical to this process, as accelerating global change makes restored and unrestored habitat health increasingly uncertain. Because western ecological restoration is fairly new and developed alongside or after other ecology subdisciplines, there are knowledge gaps in our ability to restore at scales that can counter global degradation. Knowledge gaps include how to 1) maintain restorations over time amidst changing climate, 2) increase restoration success by partitioning controllable vs. uncontrollable factors, and 3) close the theory-application loop by using theory to predict natural systems, and natural systems to inform theory. This dissertation uses experimental and non-experimental data to investigate how factors within and outside manager control structure grassland plant communities across southern Nebraska. In a new 3-year experiment I tested the impact of seed mix (mid- and high-diversity) and haying on flowering phenology in old hay meadow restoration. Haying significantly increased flower abundance regardless of seed mix, but extra work is needed to ensure critical spring blossoms are predominantly native, pollinator-preferred species. Non-experimental data from collaborators encompassed 19 years of sampling and 42 grassland sites (including 23 never-plowed remnants). Using those data, I explored interdecadal plant diversity in restorations, partitioned the effects of soils and management on restorations and remnants, and partitioned variance of major functional groups over five years. Plant diversity in restorations accumulated and persisted over 19 years. Sampling year, soils, and management impact grassland community composition, and sampling year and soils also impact plant diversity. Variation within plant communities is largely stable over time, with sites being variable but not differing between remnants and restorations. Overall, grasslands act similarly over time regardless of restoration/remnant status and high spatial variability. More species-targeted, intensive sampling may be required to detect critical sources of variation within non-experimental plant communities.
Subject Area
Ecology|Conservation biology|Natural Resource Management
Recommended Citation
Hogan, Katharine Faith Eileen, "Different Legacies, Similar Journeys: How Factors Within and Outside Management Control Structure Prairie Restorations and Remnants" (2022). ETD collection for University of Nebraska-Lincoln. AAI29999506.
https://digitalcommons.unl.edu/dissertations/AAI29999506