Episodic occurrence of favorable weather constrains recovery of a cold desert shrubland after fire

1. Key to the long-term resilience of dryland ecosystems is the recovery of foundation plant species following disturbance. In ecosystems with high interannual weather variability, understanding the influence of short-term environmental conditions on establishment of foundation species is essential for identifying vulnerable landscapes and developing restoration strategies. We asked how annual environmental conditions affect post-fire establishment of Artemisia tridentata, a shrub species that dominates landscapes across much of the western United States, and evaluated the influence of episodic establishment on population recovery. 2. We collected A. tridentata stem samples from 33 plots in 12 prescribed fire sites that burned 8-11 years before sampling. We determined individual establishment years using annual growth rings. We measured seasonal soil environmental conditions at the study sites and asked if these conditions predicted annual establishment density. We then evaluated whethe...

1. 旱地生态系统长期韧性的核心，在于受干扰后建群植物种（foundation plant species）的恢复。在年际天气变率（interannual weather variability）较高的生态系统中，明晰短期环境条件对建群物种定植的影响，是识别脆弱景观、制定生态修复策略的必要前提。本研究旨在探究年度环境条件如何影响三齿蒿（Artemisia tridentata）的火烧后定植——该灌木是美国西部多数区域的景观优势物种，并评估了偶发定植对种群恢复的作用。
2. 我们在采样前8至11年发生过火的12个计划火烧样地内，共采集了33个样方的三齿蒿茎秆样本。通过年轮（annual growth rings）测定了每株个体的定植年份。我们测定了研究样地的季节性土壤环境条件，并探究这些环境条件能否预测年度定植密度；随后评估了……