PARENT SESSION
Contributed Oral Session 152: Biodiversity: Soils; Seeds
Friday, August 12, 8:00 AM - 11:30 AM, Meeting Room 513 E, Level 5, Palais des congrès de Montréal
Linking acid rain, soil properties, and avian biodiversity in four regions of New York.
Hames, Ralph*,1, Lowe, James1, 1 Cornell Laboratory of Ornithology, Ithaca, NY, United States
ABSTRACT- Acid deposition due to fog, rain, and snow has been linked to declines in the abundance and diversity of birds in affected regions of Europe. Studies have demonstrated that these declines were caused by decreases in the abundance of calcium-rich prey (that are necessary for reproductive success in many breeding birds), due to leaching of calcium from the soil, and also linked to alterations in vegetation. Such loss of avian diversity has not been seen in North America, although recent research has linked declines in the abundance of some bird species to acid rain. We report the results of a study of avian biodiversity, calcium-rich prey, and soil properties at 40 sites across four regions of New York receiving different amounts of acidic deposition. At each site, we used standard 10-minute point counts and playback of alarm calls to sample avian diversity and collected samples of calcium-rich invertebrates and soil to test whether avian diversity varied with soil properties and invertebrate abundance. We show that the number, but not the biomass, of calcium-rich invertebrates (isopods, myriapods, and gastropods) declined significantly with declines in soil pH and calcium content. Bird biomass and abundance also decline with declining pH, but neither were significantly related to soil calcium content. Likewise, avian species richness also decreased significantly with declines in soil pH, but there was no significant relationship between species richness and soil calcium content; neither Hurlburt's PIE nor Simpsons's Reciprocal Index (1/D) were significantly related to soil properties. We suggest alternate explanations for these results and detail future research.
Key words: atmospheric deposition, invertebrate prey, calcium depletion