Dataset Information

Spatial models reveal the microclimatic buffering capacity of old-growth forests.

ABSTRACT: Climate change is predicted to cause widespread declines in biodiversity, but these predictions are derived from coarse-resolution climate models applied at global scales. Such models lack the capacity to incorporate microclimate variability, which is critical to biodiversity microrefugia. In forested montane regions, microclimate is thought to be influenced by combined effects of elevation, microtopography, and vegetation, but their relative effects at fine spatial scales are poorly known. We used boosted regression trees to model the spatial distribution of fine-scale, under-canopy air temperatures in mountainous terrain. Spatial models predicted observed independent test data well (r = 0.87). As expected, elevation strongly predicted temperatures, but vegetation and microtopography also exerted critical effects. Old-growth vegetation characteristics, measured using LiDAR (light detection and ranging), appeared to have an insulating effect; maximum spring monthly temperatures decreased by 2.5°C across the observed gradient in old-growth structure. These cooling effects across a gradient in forest structure are of similar magnitude to 50-year forecasts of the Intergovernmental Panel on Climate Change and therefore have the potential to mitigate climate warming at local scales. Management strategies to conserve old-growth characteristics and to curb current rates of primary forest loss could maintain microrefugia, enhancing biodiversity persistence in mountainous systems under climate warming.

SUBMITTER: Frey SJ

PROVIDER: S-EPMC4846426 | biostudies-literature | 2016 Apr

REPOSITORIES: biostudies-literature

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Spatial models reveal the microclimatic buffering capacity of old-growth forests.

Frey Sarah J K SJ Hadley Adam S AS Johnson Sherri L SL Schulze Mark M Jones Julia A JA Betts Matthew G MG

Science advances 20160422 4

Climate change is predicted to cause widespread declines in biodiversity, but these predictions are derived from coarse-resolution climate models applied at global scales. Such models lack the capacity to incorporate microclimate variability, which is critical to biodiversity microrefugia. In forested montane regions, microclimate is thought to be influenced by combined effects of elevation, microtopography, and vegetation, but their relative effects at fine spatial scales are poorly known. We u ...[more]

PMID: 27152339

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Spatial models reveal the microclimatic buffering capacity of old-growth forests.

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Spatial models reveal the microclimatic buffering capacity of old-growth forests.

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