Climatic patterns and the distribution of C4 grasses in North America.

摘要: A stepwise multiple regression analysis was used in an attempt to correlate statistically the geographic patterns abundance of C4 grasses with climatic variables. The percent having pathway computed for total grass flora twenty-seven widely spaced regions North America. From long-term records seasonal and annual values solar irradiance, water supply, heat availability, combinations these variables were assigned each twentyseven regions. results suggest that high minimum temperatures during growing season have strongest correlation relative species a regional flora. It appears deleterious effects low growth negate advantages possessing cooler habitats.