The changing biodiversity of Alabama : important impacts of seasonal variation, urbanization, and invasive species.

Global warming and anthropogenic disturbances significantly influence the biosphere, tremendously increasing species extinction rates. In Central Alabama, we analyzed Drosophilidae species composition change nearly 100 years after the previous survey. We found ten Drosophilid species that were not reported during the last major biodiversity studies, two of which are invasive pests. In addition, we analyzed the influence of seasonal environmental variables characteristic of the subtropical climate zone on abundance and biodiversity. We found a significant correlation between temperature and abundance of total as well as for six of the seven most represented species individually, with a maximum abundance at intermediate temperatures (18-26°C). In addition, temperature was positively correlated with biodiversity of . Precipitation produced a significant effect on the abundance of five species of Drosophila, with different optima for each species, but did not affect overall biodiversity. We concluded that in the subtropical climate zone of Central Alabama, seasonal temperature and precipitation changes produce a significant effect on abundance and biodiversity, while local land use also impacts fly abundance, contributing to an apparent shift in species composition over the last century. We expect global climate change and other anthropogenic factors to further impact species composition in the subtropical climate zone into the future.