气候变化领域集成服务门户(CCPortal): Soil moisture regime and canopy closure structure subalpine understory development during the first three decades following fire

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DOI	10.1016/j.foreco.2020.118783
	Soil moisture regime and canopy closure structure subalpine understory development during the first three decades following fire
	Andrade A.J.; Tomback D.F.; Seastedt T.R.; Mellmann-Brown S.
发表日期	2020
ISSN	0378-1127
英文摘要	Subalpine coniferous forests are adapted to cycles of fire and successional development, but increasing fire frequency and severity are altering historical stand structure, composition, and plant diversity. For instance, conifer regeneration has become increasingly variable as a result of prolonged aridity following fire, but the potential cascading effects on understory community development remain virtually unexplored. We used a natural experiment to investigate the relationships among understory plant succession, soil moisture regime, and variable tree canopy development over 30 years following the 1988 fires in the Greater Yellowstone Ecosystem, U.S.A. In 1990, at each of two study areas, plots were established in different site types defined by burn status (burned or unburned) and soil moisture regime (mesic or xeric), determined using biophysical indicators. We asked: (1) Are differences in soil moisture regime associated with differences in understory community composition (species richness, diversity, and functional group representation) during the first three decades after fire? (2) Does the relationship between soil moisture regime and community composition change over time as subcanopy (height >137 cm) tree densities increase? We confirmed our original designations of soil moisture regime using in situ measurements of soil moisture. Over the first decade of succession, species richness and diversity were lower in xeric-burned than in mesic-burned plots. Nearly 30 years after fire at the south-aspect study area, where subcanopy tree densities were low, seral understories diverged by soil moisture regime. There, graminoid cover was 23-fold higher, and forb cover was 3-fold lower, in xeric-burned than in mesic-burned plots. In contrast, in the mixed aspect study area, subcanopy tree densities were markedly higher. There, the understory did not vary by soil moisture regime, appearing to converge successionally and becoming more similar to unburned forest communities. Our results suggest that site-specific soil moisture regimes structure the early trajectory of post-fire understory recovery, but the relationship diminishes as tree canopies develop over time. However, under a warming climate, variable tree canopy development may compound increasing aridity, particularly on xeric sites, resulting in decreases in plant diversity and forb cover, increases in graminoid cover, and the potential for altered successional dynamics. © 2020 Elsevier B.V.
英文关键词	1988 Yellowstone fires; Canopy closure; Conifer regeneration; Soil moisture regime; Succession; Understory
语种	英语
scopus关键词	Ecology; Fires; Reforestation; Soil moisture; Biophysical indicators; Community composition; Group representation; In-situ measurement; Increasing aridities; Species richness and diversities; Subalpine coniferous forests; Understory communities; Soil surveys
来源期刊	Forest Ecology and Management
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/155623
作者单位	Department of Integrative Biology, CB171, University of Colorado Denver, P.O. Box 173364, Denver, CO 80217, United States; Department of Ecology and Evolutionary Biology and INSTAAR, University of Colorado Boulder, Boulder, CO UCB 450, United States; USDA Forest Service, Northern Region, 24 Fort Missoula, Missoula, MT 59804, United States
推荐引用方式 GB/T 7714	Andrade A.J.,Tomback D.F.,Seastedt T.R.,et al. Soil moisture regime and canopy closure structure subalpine understory development during the first three decades following fire[J],2020.
APA	Andrade A.J.,Tomback D.F.,Seastedt T.R.,&Mellmann-Brown S..(2020).Soil moisture regime and canopy closure structure subalpine understory development during the first three decades following fire.Forest Ecology and Management.
MLA	Andrade A.J.,et al."Soil moisture regime and canopy closure structure subalpine understory development during the first three decades following fire".Forest Ecology and Management (2020).