Ecosystem change along a woody invasion chronosequence in a California grassland
نویسنده
چکیده
Woody species have increased in abundance in many grassland ecosystems during the last century. To investigate the consequences of Baccharis pilularis encroachment into coastal California grasslands, we established a chronosequence of sites naturally invaded by Baccharis zero to 25 years ago. Increasing aboveand below-ground biomass increase along the chronosequence drove increases in ecosystem N sequestration of 700% and in C storage of over 125%. Colonization by oaks (Quercus agrifolia) and other woody species at sites colonized by Baccharis 415 years ago indicate that the progressive ecosystem changes observed in chronosequence reinforce woody dominance and associated changes at shrub-invaded sites. r 2005 Elsevier Ltd. All rights reserved.
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