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Terrestrial ecosystems are critical to human welfare and regulating Earth’s life support systems but many gaps in our knowledge remain regarding how terrestrial plant communities respond to changes in climate or human actions. I used field experiments distributed across three dryland ecosystems in North America to evaluate the consequences of changing precipitation and physical disturbance on plant community structure and function. Evidence from experiments and observational work exploring both plant community composition and ecological processes suggest that physical disturbance and precipitation reductions can reduce the diversity and function of these dryland ecosystems. Specifically, I found that aboveground net primary productivity could be reduced in an interactive manner when precipitation reductions and physical disturbance co-occur, and that within sites, this reduction in productivity was greater when growing-season precipitation was low. Further, I found that these dryland plant communities, commonly dominated by highly drought-resistant shrubs and perennial grasses, were not capable of compensating for the absence of these dominant shrubs and perennial grasses when they were removed by disturbance, and that precipitation reductions (as predicted to occur from anthropogenic climate change) exacerbate these gaps. Collectively, the results of the field experiment suggest that current management paradigms of maintaining cover and structure of native perennial plants in dryland systems are well founded and may be especially important as climate variability increases over time. Evaluating how these best management practices take place in the real world is an important extension of fundamental ecological research. To address the research-management gap in the context of dryland ecosystems in the western US, I used a set of environmental management plans and remotely sensed data to investigate how ecosystem services in drylands are accounted for, both as a supply from the land base and as a demand from stakeholders. Focusing on a less-investigated land base in the United States–areas owned and managed by the Department of Defense–I explored how ecosystem services are produced by this unique land management arrangement even if they are not explicitly managed for under current management schemes. My findings support a growing body of evidence that Department of Defense lands represent a valuable conservation opportunity, both for biodiversity and ecosystem services, if management regimes fully integrate the ecosystem services concept.
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Looking Back for the Future: The Ecology of Terrestrial Communities Through the Lens of Conservation Paleobiology
Terrestrial ecosystems encompass a vast and vital component of Earth's biodiversity and ecosystem services. The effect of increased anthropogenic dominance on terrestrial communities defines major challenges for ecosystem conservation, including habitat destruction and fragmentation, climate change, species invasions and extinctions, and disease spread. Here, we integrate fossil, historical, and present-day organismal and ecological data to investigate how conservation paleobiology provides deep-time perspectives on terrestrial organisms, populations, communities, and ecosystems impacted by anthropogenic processes. We relate research tools to conservation outputs and highlight gaps that currently limit conservation paleobiology from reaching its full impact on conservation practice and management. In doing so, we also highlight how the colonial legacies of conservation biology and paleobiology confound our understanding of present-day biodiversity, ecosystem processes, and conservation outlooks, and we make recommendations for more inclusive and ethical practices moving forward.
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- Award ID(s):
- 2050228
- PAR ID:
- 10538409
- Publisher / Repository:
- Annual Reviews
- Date Published:
- Journal Name:
- Annual Review of Ecology, Evolution, and Systematics
- Volume:
- 54
- Issue:
- 1
- ISSN:
- 1543-592X
- Page Range / eLocation ID:
- 259 to 282
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1146/annurev-ecolsys-110421-101343
