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Title: Evidence of Competitive Release Following Overstory Mortality in a Semi-Arid Piñon-Juniper Woodland
Extreme temperatures and severe drought events have led to widespread tree mortality worldwide. In semi-arid regions of the Southwest United States, these events pose a significant threat to piñon-juniper (PJ) woodlands. We studied the effects of piñon and juniper mortality on the growth and physiology of existing saplings in PJ woodlands by analyzing water status, photosynthetic activity, and tissue chemistry to gain insights into these impacts. Juniper saplings exhibited improved water status and water use efficiency in response to overstory mortality, whereas piñon saplings did not. Additionally, both piñon and juniper saplings exhibited increased photosynthetic rates, increased photosynthetic capacity, and enhanced growth rates. Our results suggest that saplings of both species responded similarly regardless of whether a mature piñon or juniper died. However, piñon saplings appeared to be more vulnerable to overstory mortality, likely due to the difference in hydraulic strategies between piñon and juniper This study enhances our understanding of the post-mortality recovery process in piñon-juniper ecosystems, providing valuable insights into the contrasting effects of piñon vs. juniper mortality as well as the distinct physiological responses exhibited by piñon and juniper saplings.  more » « less
Award ID(s):
1655499
PAR ID:
10511388
Author(s) / Creator(s):
Publisher / Repository:
Digital Commons Network
Date Published:
Journal Name:
University of New Mexico Publications in Biology
ISSN:
0099-3883
Subject(s) / Keyword(s):
Ecophysiology, PJ woodlands, Sapling physiology, Southwest
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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