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Hajek OL, Knapp AK. Signatures of autumn deluges revealed during spring drought in a semi-arid grassland. Oecologia 2024; 204:83-93. [PMID: 38108892 DOI: 10.1007/s00442-023-05488-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Accepted: 11/08/2023] [Indexed: 12/19/2023]
Abstract
Increases in extremely large precipitation events (deluges) and shifts in seasonal patterns of water availability with climate change will both have important consequences for ecosystem function, particularly in water-limited regions. While previous work in the semi-arid shortgrass steppe of northeastern Colorado has demonstrated this ecosystem's strong sensitivity to growing season deluges, our understanding of ecosystem responses to deluges during the dormant season is limited. Here, we imposed experimental 100 mm deluges (~ 30% of mean annual precipitation) in either September or October in a native C4-dominated shortgrass steppe ecosystem to evaluate the impact of this post-growing season shift in water availability during the autumn and the following growing season. Soil moisture for both deluge treatments remained elevated compared with ambient levels through April as spring precipitation was atypically low. Despite overall low levels of productivity with spring drought, these deluges from the previous autumn increased aboveground net primary production (ANPP), primarily due to increases with C4 grasses. C3 ANPP was also enhanced, largely due to an increase in the annual C3 grass, Vulpia octoflora, in the October deluge treatment. While spring precipitation has historically been the primary determinant of ecosystem function in this ecosystem, this combination of two climate extremes-an extremely wet autumn followed by a naturally-occurring spring drought-revealed the potential for meaningful carryover effects from autumn precipitation. With climate change increasing the likelihood of extremes during all seasons, experiments which create novel climatic conditions can provide new insight into the dynamics of ecosystem functioning in the future.
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Affiliation(s)
- Olivia L Hajek
- Graduate Degree Program in Ecology and Department of Biology, Colorado State University, Fort Collins, CO, 80523, USA.
| | - Alan K Knapp
- Graduate Degree Program in Ecology and Department of Biology, Colorado State University, Fort Collins, CO, 80523, USA
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Bao F, Xin Z, Li J, Liu M, Cao Y, Lu Q, Gao Y, Wu B. Effects of the Simulated Enhancement of Precipitation on the Phenology of Nitraria tangutorum under Extremely Dry and Wet Years. PLANTS 2021; 10:plants10071474. [PMID: 34371677 PMCID: PMC8309252 DOI: 10.3390/plants10071474] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 07/06/2021] [Accepted: 07/15/2021] [Indexed: 11/16/2022]
Abstract
Plant phenology is the most sensitive biological indicator that responds to climate change. Many climate models predict that extreme precipitation events will occur frequently in the arid areas of northwest China in the future, with an increase in the quantity and unpredictability of rain. Future changes in precipitation will inevitably have a profound impact on plant phenology in arid areas. A recent study has shown that after the simulated enhancement of precipitation, the end time of the leaf unfolding period of Nitraria tangutorum advanced, and the end time of leaf senescence was delayed. Under extreme climatic conditions, such as extremely dry or wet years, it is unclear whether the influence of the simulated enhancement of precipitation on the phenology of N. tangutorum remains stable. To solve this problem, this study systematically analyzed the effects of the simulated enhancement of precipitation on the start, end and duration of four phenological events of N. tangutorum, including leaf budding, leaf unfolding, leaf senescence and leaf fall under extremely dry and wet conditions. The aim of this study was to clarify the similarities and differences of the effects of the simulated enhancement of precipitation on the start, end and duration of each phenological period of N. tangutorum in an extremely dry and an extremely wet year to reveal the regulatory effect of extremely dry and excessive amounts of precipitation on the phenology of N. tangutorum. (1) After the simulated enhancement of precipitation, the start and end times of the spring phenology (leaf budding and leaf unfolding) of N. tangutorum advanced during an extremely dry and an extremely wet year, but the duration of phenology was shortened during an extremely wet year and prolonged during an extremely drought-stricken year. The amplitude of variation increased with the increase in simulated precipitation. (2) After the simulated enhancement of precipitation, the start and end times of the phenology (leaf senescence and leaf fall) of N. tangutorum during the autumn advanced in an extremely wet year but was delayed during an extremely dry year, and the duration of phenology was prolonged in both extremely dry and wet years. The amplitude of variation increased with the increase in simulated precipitation. (3) The regulation mechanism of extremely dry or wet years on the spring phenology of N. tangutorum lay in the different degree of influence on the start and end times of leaf budding and leaf unfolding. However, the regulation mechanism of extremely dry or wet years on the autumn phenology of N. tangutorum lay in different reasons. Water stress caused by excessive water forced N. tangutorum to start its leaf senescence early during an extremely wet year. In contrast, the alleviation of drought stress after watering during the senescence of N. tangutorum caused a delay in the autumn phenology during an extremely dry year.
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Affiliation(s)
- Fang Bao
- Institute of Desertification Studies, Chinese Academy of Forestry, Beijing 100091, China; (J.L.); (Y.C.); (Q.L.); (Y.G.)
- Key Laboratory for Desert Ecosystem and Global Change, Chinese Academy of Forestry, Beijing 100091, China
- Correspondence: (F.B.); (B.W.)
| | - Zhiming Xin
- Experimental Center of Desert Forestry, Chinese Academy of Forestry, Dengkou 015200, China; (Z.X.); (M.L.)
- Inner Mongolia Dengkou Desert Ecosystem National Observation Research Station, Dengkou 015200, China
| | - Jiazhu Li
- Institute of Desertification Studies, Chinese Academy of Forestry, Beijing 100091, China; (J.L.); (Y.C.); (Q.L.); (Y.G.)
- Key Laboratory for Desert Ecosystem and Global Change, Chinese Academy of Forestry, Beijing 100091, China
| | - Minghu Liu
- Experimental Center of Desert Forestry, Chinese Academy of Forestry, Dengkou 015200, China; (Z.X.); (M.L.)
| | - Yanli Cao
- Institute of Desertification Studies, Chinese Academy of Forestry, Beijing 100091, China; (J.L.); (Y.C.); (Q.L.); (Y.G.)
- Key Laboratory for Desert Ecosystem and Global Change, Chinese Academy of Forestry, Beijing 100091, China
| | - Qi Lu
- Institute of Desertification Studies, Chinese Academy of Forestry, Beijing 100091, China; (J.L.); (Y.C.); (Q.L.); (Y.G.)
| | - Ying Gao
- Institute of Desertification Studies, Chinese Academy of Forestry, Beijing 100091, China; (J.L.); (Y.C.); (Q.L.); (Y.G.)
- Key Laboratory for Desert Ecosystem and Global Change, Chinese Academy of Forestry, Beijing 100091, China
| | - Bo Wu
- Institute of Desertification Studies, Chinese Academy of Forestry, Beijing 100091, China; (J.L.); (Y.C.); (Q.L.); (Y.G.)
- Key Laboratory for Desert Ecosystem and Global Change, Chinese Academy of Forestry, Beijing 100091, China
- Correspondence: (F.B.); (B.W.)
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Bao F, Liu M, Cao Y, Li J, Yao B, Xin Z, Lu Q, Wu B. Water Addition Prolonged the Length of the Growing Season of the Desert Shrub Nitraria tangutorum in a Temperate Desert. FRONTIERS IN PLANT SCIENCE 2020; 11:1099. [PMID: 32793260 PMCID: PMC7386313 DOI: 10.3389/fpls.2020.01099] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 07/03/2020] [Indexed: 06/11/2023]
Abstract
Climate models often predict that more extreme precipitation events will occur in arid and semiarid regions, where plant phenology is particularly sensitive to precipitation changes. To understand how increases in precipitation affect plant phenology, this study conducted a manipulative field experiment in a desert ecosystem of northwest China. In this study, a long-term in situ water addition experiment was conducted in a temperate desert in northwestern China. The following five treatments were used: natural rain plus an additional 0, 25, 50, 75, and 100% of the local mean annual precipitation. A series of phenological events, including leaf unfolding (onset, 30%, 50%, and end of leaf unfolding), cessation of new branch elongation (30, 50, and 90%), and leaf coloration (80% of leaves turned yellow), of the locally dominant shrub Nitraria tangutorum were observed from 2012 to 2018. The results showed that on average, over the seven-year-study and in all treatments water addition treatments advanced the spring phenology (30% of leaf unfolding) by 1.29-3.00 days, but delayed the autumn phenology (80% of leaves turned yellow) by 1.18-11.82 days. Therefore, the length of the growing season was prolonged by 2.11-13.68 days, and autumn phenology contributed more than spring phenology. In addition, water addition treatments delayed the cessation of new branch elongation (90%) by 5.82-12.61 days, and nonlinear relationships were found between the leaves yellowing (80% of leaves) and the amount of watering. Linear relationships were found between the cessation of new branch elongation (90%), the length of the growing season, and amount of water addition. The two response patterns to water increase indicated that predictions of phenological events in the future should not be based on one trend only.
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Affiliation(s)
- Fang Bao
- Institute of Desertification Studies, Chinese Academy of Forestry, Beijing, China
- Key Laboratory for Desert Ecosystem and Global Change, Chinese Academy of Forestry, Beijing, China
| | - Minghu Liu
- Experimental Center of Desert Forestry, Chinese Academy of Forestry, Dengkou, China
| | - Yanli Cao
- Institute of Desertification Studies, Chinese Academy of Forestry, Beijing, China
| | - Jiazhu Li
- Institute of Desertification Studies, Chinese Academy of Forestry, Beijing, China
| | - Bin Yao
- Institute of Desertification Studies, Chinese Academy of Forestry, Beijing, China
| | - Zhiming Xin
- Experimental Center of Desert Forestry, Chinese Academy of Forestry, Dengkou, China
- Inner Mongolia Dengkou Desert Ecosystem National Observation Research Station, Dengkou, China
| | - Qi Lu
- Institute of Desertification Studies, Chinese Academy of Forestry, Beijing, China
- Experimental Center of Desert Forestry, Chinese Academy of Forestry, Dengkou, China
| | - Bo Wu
- Institute of Desertification Studies, Chinese Academy of Forestry, Beijing, China
- Key Laboratory for Desert Ecosystem and Global Change, Chinese Academy of Forestry, Beijing, China
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Identification of suites of traits that explains drought resistance and phenological patterns of plants in a semi-arid grassland community. Oecologia 2020; 192:55-66. [PMID: 31932921 DOI: 10.1007/s00442-019-04567-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 11/22/2019] [Indexed: 11/25/2022]
Abstract
Grassland ecosystems are comprised of plants that occupy a wide array of phenological niches and vary considerably in their ability to resist the stress of seasonal soil-water deficits. Yet, the link between plant drought resistance and phenology remains unclear in perennial grassland ecosystems. To evaluate the role of soil water availability and plant drought tolerance in driving phenology, we measured leaf hydraulic conductance (Ksat), resistance to hydraulic failure (P50), leaf gas exchange, plant and soil water stable isotope ratios (δ18O), and several phenology metrics on ten perennial herbaceous species in mixed-grass prairie. The interaction between P50 and δ18O of xylem water explained 67% of differences in phenology, with lower P50 values associated with later season activity, but only among shallow-rooted species. In addition, stomatal control and high water-use efficiency also contributed to the late flowering and late senescence strategies of plants that had low P50 values and relied upon shallow soil water. Alternatively, plants with deeper roots did not possess drought-tolerant leaves, but had high hydraulic efficiency, contributing to their ability to efficiently move water longer distances while maintaining leaf water potential at relatively high values. The suites of traits that characterize these contrasting strategies provide a mechanistic link between phenology and plant-water relations; thus, these traits could help predict grassland community responses to changes in water availability, both temporally and vertically within the soil profile.
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Reed PB, Pfeifer‐Meister LE, Roy BA, Johnson BR, Bailes GT, Nelson AA, Boulay MC, Hamman ST, Bridgham SD. Prairie plant phenology driven more by temperature than moisture in climate manipulations across a latitudinal gradient in the Pacific Northwest, USA. Ecol Evol 2019; 9:3637-3650. [PMID: 30962915 PMCID: PMC6434541 DOI: 10.1002/ece3.4995] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 01/26/2019] [Indexed: 01/24/2023] Open
Abstract
Plant phenology will likely shift with climate change, but how temperature and/or moisture regimes will control phenological responses is not well understood. This is particularly true in Mediterranean climate ecosystems where the warmest temperatures and greatest moisture availability are seasonally asynchronous. We examined plant phenological responses at both the population and community levels to four climate treatments (control, warming, drought, and warming plus additional precipitation) embedded within three prairies across a 520 km latitudinal Mediterranean climate gradient within the Pacific Northwest, USA. At the population level, we monitored flowering and abundances in spring 2017 of eight range-restricted focal species planted both within and north of their current ranges. At the community level, we used normalized difference vegetation index (NDVI) measured from fall 2016 to summer 2018 to estimate peak live biomass, senescence, seasonal patterns, and growing season length. We found that warming exerted a stronger control than our moisture manipulations on phenology at both the population and community levels. Warming advanced flowering regardless of whether a species was within or beyond its current range. Importantly, many of our focal species had low abundances, particularly in the south, suggesting that establishment, in addition to phenological shifts, may be a strong constraint on their future viability. At the community level, warming advanced the date of peak biomass regardless of site or year. The date of senescence advanced regardless of year for the southern and central sites but only in 2018 for the northern site. Growing season length contracted due to warming at the southern and central sites (~3 weeks) but was unaffected at the northern site. Our results emphasize that future temperature changes may exert strong influence on the timing of a variety of plant phenological events, especially those events that occur when temperature is most limiting, even in seasonally water-limited Mediterranean ecosystems.
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Affiliation(s)
- Paul B. Reed
- Institute of Ecology and EvolutionUniversity of OregonEugeneOregon
- Environmental Studies ProgramUniversity of OregonEugeneOregon
| | | | - Bitty A. Roy
- Institute of Ecology and EvolutionUniversity of OregonEugeneOregon
| | - Bart R. Johnson
- Department of Landscape ArchitectureUniversity of OregonEugeneOregon
| | - Graham T. Bailes
- Institute of Ecology and EvolutionUniversity of OregonEugeneOregon
| | - Aaron A. Nelson
- Institute of Ecology and EvolutionUniversity of OregonEugeneOregon
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Blumenthal DM, Mueller KE, Kray JA, LeCain DR, Pendall E, Duke S, Zelikova TJ, Dijkstra FA, Williams DG, Morgan JA. Warming and Elevated CO2 Interact to Alter Seasonality and Reduce Variability of Soil Water in a Semiarid Grassland. Ecosystems 2018. [DOI: 10.1007/s10021-018-0237-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Moore LM, Lauenroth WK. Differential effects of temperature and precipitation on early‐ vs. late‐flowering species. Ecosphere 2017. [DOI: 10.1002/ecs2.1819] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Affiliation(s)
- Lynn M. Moore
- Department of Botany University of Wyoming 1000 E. University Avenue Laramie Wyoming 82071 USA
| | - William K. Lauenroth
- Department of Botany University of Wyoming 1000 E. University Avenue Laramie Wyoming 82071 USA
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Moore LM, Lauenroth WK. Twelve Years of High-Resolution Near-Surface Radiometer Data Provides Insight into End-of-Season Controls in a Dry Grassland. WEST N AM NATURALIST 2016. [DOI: 10.3398/064.076.0202] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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