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Rapid climate change poses a fundamental challenge to seed sourcing in restoration. While local provenancing is a common practice in restoration, local seeds may not survive or persist under future climate conditions. Alternative provenancing strategies, such as climate‐adjusted provenancing, that mix local seeds with non‐local seeds aim to increase the buffering capacity of restored populations. We hypothesized that seeds sourced from warmer and drier sites have higher seedling performance under drought than seeds sourced from cooler and wetter sites. We conducted a common garden experiment in a Great Basin rangeland where more frequent, severe drought events are expected to increase in the future. We sourced Bottlebrush squirreltail (Elymus elymoides[Raf.] Swezey) seeds from six locations along an aridity gradient and sowed them under three rainfall scenarios: ambient, moderate drought, and severe drought. We found strong interannual variation in seedling recruitment. In 1 year, some provenances from warmer/drier sites had high emergence and subsequent seedling survival under moderate drought. In another, emergence was low across provenances and rainfall treatments. Two provenances that survived 2 years of moderate drought had divergent seedling traits. Specifically, one had a high germination temperature optimum and high water‐use efficiency, such that it likely avoided freezing and resisted drought, while another had a low germination temperature optimum and low water‐use efficiency, such that it likely tolerated freezing and escaped drought. We highlight that understanding these differences in recruitment and stress coping strategies across provenances is important for creating climate‐adaptive seed mixes in anticipation of future climate conditions.
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The timing of unprecedented hydrological drought under climate change
Abstract Droughts that exceed the magnitudes of historical variation ranges could occur increasingly frequently under future climate conditions. However, the time of the emergence of unprecedented drought conditions under climate change has rarely been examined. Here, using multimodel hydrological simulations, we investigate the changes in the frequency of hydrological drought (defined as abnormally low river discharge) under high and low greenhouse gas concentration scenarios and existing water resource management measures and estimate the time of the first emergence of unprecedented regional drought conditions centered on the low-flow season. The times are detected for several subcontinental-scale regions, and three regions, namely, Southwestern South America, Mediterranean Europe, and Northern Africa, exhibit particularly robust results under the high-emission scenario. These three regions are expected to confront unprecedented conditions within the next 30 years with a high likelihood regardless of the emission scenarios. In addition, the results obtained herein demonstrate the benefits of the lower-emission pathway in reducing the likelihood of emergence. The Paris Agreement goals are shown to be effective in reducing the likelihood to the unlikely level in most regions. However, appropriate and prior adaptation measures are considered indispensable when facing unprecedented drought conditions. The results of this study underscore the importance of improving drought preparedness within the considered time horizons.
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- Award ID(s):
- 1752729
- PAR ID:
- 10414946
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 13
- Issue:
- 1
- ISSN:
- 2041-1723
- 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/10.1038/s41467-022-30729-2
