Process-Based Modeling to Assess the Effects of Recent Climatic Variation on Site Productivity and Forest Function across Western North America

Forests

Richard H Waring²  Nicholas C Coops¹  Amanda Mathys¹  Thomas Hilker² 

[1] Department of Forest Resource Management, 2424 Main Mall, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; E-Mail:;College of Forestry, Oregon State University, Corvallis, OR 97331, USA; E-Mails:

关键词: climate change;    3-PG model;    productivity;    leaf area index;    Douglas-fir;    FIA survey plots;   

DOI  :  10.3390/f5030518

来源: mdpi

【 摘 要 】

A process-based forest growth model, 3-PG (Physiological Principles Predicting Growth), parameterized with values of soil properties constrained by satellite-derived estimates of maximum leaf area index (LAI_max), was run for Douglas-fir (Pseudotsuga menziesii) to contrast the extent to which site growth potential might vary across western North America between a cool, wet period (1950–1975) and a more recent, generally warmer and drier one (2000–2009). LAI_max represents a surrogate for overall site growth potential, as demonstrated from a strong correlation between the two variables, with the latter based on the culmination of mean annual increment estimates made at 3356 ground-based U.S. Forest Service survey plots across the states of Oregon and Washington. Results indicate that since 2000, predicted LAI_max has decreased more than 20% in portions of the Southwest USA and for much of the forested area in western Alberta. Similar percentage increases in LAI_max were predicted for parts of British Columbia, Idaho and Montana. The modeling analysis included an assessment of changes in seasonal constraints on gross primary production (GPP). A general reduction in limitations caused by spring frost occurred across the entire study area. This has led to a longer growing season, along with notable increases in summer evaporative demand and soil drought for much of the study area away from the maritime influence of the Pacific Ocean.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.