Journal
NEW PHYTOLOGIST
Volume 179, Issue 1, Pages 142-154Publisher
WILEY
DOI: 10.1111/j.1469-8137.2008.02429.x
Keywords
atmospheric nitrogen deposition; climate change; decomposition; gas exchange; nutrient; peat; photosynthesis; respiration
Categories
Ask authors/readers for more resources
Nitrogen and phosphorus were added experimentally in a bog in the southern Alps. It was hypothesized that alleviating nutrient limitation will increase vascular plant cover. As a consequence, more carbon will be fixed through higher rates of net ecosystem CO2 exchange (NEE). The vascular cover did increase at the expense of Sphagnum mosses. However, such vegetation changes were largely independent of the treatment and were probably triggered by an exceptional heatwave in summer 2003. Contrary to the tested hypothesis, NEE was unaffected by the nutrient treatments but was strongly influenced by temperature and water-table depth. In particular, ecosystem respiration in the hot summer of 2003 increased dramatically, presumably owing to enhanced heterotrophic respiration in an increased oxic peat layer. At the end of the experiment, the Sphagnum cover decreased significantly in the nitrogen-fertilized treatment at hummock microhabitats. In the long term, this will imply a proportionally greater accumulation of vascular litter, more easily decomposable than the recalcitrant Sphagnum litter. As a result, rates of carbon fixation may decrease because of stimulated respiration.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available