PARENT SESSION
Tuesday, August 8, 1:30-5:00 pm
OOS 5 - Climate change and timing in ecological communities
Ballroom C, Ballroom Level, Cook Convention Center
Organized by: AJ Miller-Rushing (ajmr@bu.edu), RB Primack, and DW Inouye
This session will present research designed to document, evaluate, and predict how phenological changes caused by climate change will impact biological communities.
Species phenology in response to climatic variability in a grassland-forest ecotone.
Alaback, Paul1, Krebs, Michael1, 1 University of Montana, Missoula, MT
ABSTRACT- Ecotones provide an important barometer of the biological effects of climate change since they are often of a product of the complex interplay between abiotic factors and species interactions. In the semi-arid continental climates of western Montana the grassland-forest ecotone presents an interesting model system in which the ecotone is a product of moisture availability, growing season and disturbance processes. We have been monitoring the behavior of over 100 species of forbs, grasses, trees and shrubs along a 3 km transect spanning 400m of elevation for 10 years on a mountain slope close to campus. We have data on soils and air temperatures for 4 locations along this transect and also have information on precipitation patterns at 70m elevation intervals. The mean date of the first flowers of each species range from March 14 for Ranunculus to early September for Artemisia species. Emergence of the first flowers of early spring species can be precisely predicted (+/- 2 days) by 12 day running means of air temperature. There is a wide range in climatic sensitivities of species, generally according to evolutionary history, flowering season, lifeform and structure. Over the 10 year period species typically range from 12-27 days from the mean date of flower emergence. The earliest dates have generally occurred over the past three years, corresponding with unusually warm spring weather. Besides patterns in phenological changes, we have also noted disappearance and invasions of both native and exotic species over the 10 year period that appear to be related to changing climatic conditions. These data should provide a sensitive baseline for monitoring the continuing effects of climate change in our region.
Key words: phenology, climate change, grassland