field experiment informs expected patterns of conifer regeneration after disturbance under changing climate conditions

• Published in: Canadian journal of forest research Vol. 45; no. 11; pp. 1607 - 1616
• Main Authors: Rother, Monica T, Thomas T. Veblen, Luke G. Furman
• Format: Journal Article
• Language: English
• Published: Ottawa NRC Research Press 01.11.2015; Canadian Science Publishing NRC Research Press
• Subjects: botanical composition; chambres à ciel ouvert; changement climatique; Climate change; Climatic changes; cobalt; Conifers; drought; ecosystems; Environmental aspects; Experiments; expérience de terrain; feu de forêt; field experiment; field experimentation; Forest dynamics; Forests; global warming; Observations; open-top chambers; pin ponderosa; Pinus ponderosa; planting; ponderosa pine; Pseudotsuga menziesii; régénération des arbres; seedlings; tree regeneration; Trees; Vegetation; Water; wildfire; wildfires; Colorado; USA, Colorado
• ISSN: 1208-6037; 0045-5067; 1208-6037
• DOI: 10.1139/cjfr-2015-0033

Climate change may inhibit tree regeneration following disturbances such as wildfire, altering post-disturbance vegetation trajectories. We implemented a field experiment to examine the effects of manipulations of temperature and water on ponderosa pine (Pinus ponderosa Douglas ex P. Lawson & C. Lawson) and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings planted in a low-elevation, recently disturbed setting of the Colorado Front Range. We implemented four treatments: warmed only (Wm), watered only (Wt), warmed and watered (WmWt), and control (Co). We found that measures of growth and survival varied significantly by treatment type. Average growth and survival was highest in the Wt plots, followed by the Co, WmWt, and Wm plots, respectively. This general trend was observed for both conifer species, although average growth and survival was generally higher in ponderosa pine than in Douglas-fir. Our findings suggest that warming temperatures and associated drought are likely to inhibit post-disturbance regeneration of ponderosa pine and Douglas-fir in low-elevation forests of the Colorado Front Range and that future vegetation composition and structure may differ notably from historic patterns in some areas. Our findings are relevant to other forested ecosystems in which a warming climate may similarly inhibit regeneration by dominant tree species.