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Abstract Climate change is causing marked shifts to historic environmental regimes, including increases in precipitation events (droughts and highly wet periods). Relative to droughts, the impacts of wet events have received less attention, despite heavy rainfall events increasing over the past century. Further, impacts of wet and dry events are often evaluated independently; yet, to persist and maintain their ecosystem functions, plant communities must be resilient to both precipitation events. This is particularly critical because while community properties can modulate the resilience (resistance, recovery, and invariability) of ecosystem functions to precipitation events, community properties can also respond to precipitation events. As a result, community responses to wet and dry years may impact the community's resilience to future events.Using two decades (2000–2020) of annual net primary productivity data from early successional grassland communities, we evaluated the plant community properties regulating primary productivity resistance and recovery to contrasting precipitation events and invariability (i.e. long‐term stability). We then explored how resilience‐modulating community properties responded to precipitation.We found that community properties—specifically, evenness, dominant species (Solidago altissima) relative abundance, and species richness—strongly regulate productivity resistance to drought and predict productivity invariability and tended to promote resistance to wet years. These community properties also responded to both wet and dry precipitation extremes and exhibited lagged responses that lasted into the next growing season. We infer that these connections between precipitation events, community properties, and resilience may lead to feedbacks impacting a plant community's resilience to subsequent precipitation events.Synthesis. By exploring the impacts of both drought and wet extremes, our work uncovers how precipitation events, which may not necessarily impact productivity directly, could still cryptically influence resilience via shifts in resilience‐promoting properties of the plant community. We conclude that these precipitation event‐driven community shifts may feedback to impact long‐term productivity resilience under climate change.
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This content will become publicly available on August 12, 2026
Herbaceous plant communities respond more to seasonal precipitation than cumulative drought in the hot deserts of the United States
Abstract The hot deserts of the southwestern United States are experiencing increased frequency, severity, and duration of drought due to anthropogenic climate change. Plant communities in these deserts differ in composition, specifically the abundance of annual and perennial species, which could differentiate responses among these ecosystems to drought. Thus, identifying how these desert plant communities respond to prolonged, severe drought is critical to assess vulnerability to climate change. We measured the response of herbaceous plant communities to 4 years of experimentally imposed severe drought in Chihuahuan, Sonoran, and Mojave Desert sites in the southwestern US.We imposed year‐round passive rain exclusion treatments with a 66% reduction in ambient rainfall for 4 years at two sites in each of the three US hot deserts. We measured plant species composition and abundance in treatment and control plots during the peak growing season.Vegetative cover increased with seasonal precipitation at all six sites. Species richness and evenness varied in response to drought across all sites over the duration of the experiment. At three of the six sites, species richness increased with seasonal precipitation and at three sites species evenness decreased with seasonal precipitation.In general, we found that community structure was linked to seasonal precipitation more so than cumulative drought in these herbaceous communities of southwestern US deserts, and that these desert communities are highly resilient following prolonged, extreme drought.
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- Award ID(s):
- 2425290
- PAR ID:
- 10654248
- Publisher / Repository:
- John Wiley & Sons, Ltd.
- Date Published:
- Journal Name:
- Plant Biology
- ISSN:
- 1435-8603
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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