The Effect of Simulated Nitrogen Deposition on the Emission of Carbonyl Compounds from Ormosia pinnata and Cinnamomum burmannii

The Effect of Simulated Nitrogen Deposition on the Emission of Carbonyl Compounds from Ormosia pinnata and Cinnamomum burmannii

Elevated anthropogenic nitrogen (N) deposition has become a limiting factor for plants instead of a nutrient for its dramatic rising at globally scale, which greatly affects the process of carbon (C) cycle from individual plant to ecosystem, and even global levels. It could affect biogenic carbonyl emissions as an important component of carbon pool from plants, but this aspect has not yet been investigated. In this study, we performed a simulated N deposition experiment (100 kg N•ha-1•y-1) on two native tree saplings planted in a nursery in South China. Results showed that three main biogenic carbonyls, i.e. formaldehyde, acetaldehyde, and acetone from tree leaves all had distinct seasonal variations, with much higher emission rates in the wet season than in the dry season. Elevated N addition significantly depressed the emission of biogenic carbonyls in the dry season, but not in the wet season. No big differences were observed in carbonyls emissions from the two tree species responding to N deposition both in the wet season and in the dry season. Thus, we concluded that N deposition might drive plants to change carbon allocation and reduce carbon loss when as a limiting factor in the dry season. This finding is of significance for the theory of carbon allocation and plant adaptability strategy under elevated N deposition.