Open AccessDramatic response to climate change in the Southwest: Robert Whittaker's 1963 Arizona Mountain plant transect revisited
Author(s) -
Brusca Richard C.,
Wiens John F.,
Meyer Wallace M.,
Eble Jeff,
Franklin Kim,
Overpeck Jonathan T.,
Moore Wendy
Publication year - 2013
Publication title -
ecology and evolution
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.17
H-Index - 63
ISSN - 2045-7758
DOI - 10.1002/ece3.720
Subject(s) - transect , montane ecology , climate change , range (aeronautics) , elevation (ballistics) , geography , vegetation (pathology) , physical geography , ecology , alpine plant , plant community , ecological succession , biology , medicine , materials science , geometry , mathematics , pathology , composite material
Models analyzing how S outhwestern plant communities will respond to climate change predict that increases in temperature will lead to upward elevational shifts of montane species. We tested this hypothesis by reexamining R obert W hittaker's 1963 plant transect in the S anta C atalina M ountains of southern A rizona, finding that this process is already well underway. Our survey, five decades after W hittaker's, reveals large changes in the elevational ranges of common montane plants, while mean annual rainfall has decreased over the past 20 years, and mean annual temperatures increased 0.25°C/decade from 1949 to 2011 in the T ucson B asin. Although elevational changes in species are individualistic, significant overall upward movement of the lower elevation boundaries, and elevational range contractions, have occurred. This is the first documentation of significant upward shifts of lower elevation range boundaries in Southwestern montane plant species over decadal time, confirming that previous hypotheses are correct in their prediction that mountain communities in the Southwest will be strongly impacted by warming, and that the Southwest is already experiencing a rapid vegetation change.