title: Temporal variability of ammonia emission potentials for six plant species in an evergreen subtropical forest in southwest China.
abstract: The temporal variability of leaf ammonia (NH3) emission potentials (the ratio of leaf tissue ammonium to proton concentration) and nitrogen (N) pools of six dominant plant species were investigated at the Tieshanping (TSP) forested catchment, southwest China. The results showed that the NH3emission potentials and N pools presented small variations among seasons, which were mainly controlled by plant species and the leaf age. Also, high emission potential in one species did not correspond to high tissue N content. Specifically, the Chinese fir (Cunninghamia lanceolata) had higher NH3emission potential (mean: 46.2) but lower N content (mean: 1.6% of Dw). The leaf privet (Ligustrum quihoui Carr.) was with the moderate emission potential (15) and the highest N content (2.7% of Dw) on average, which for the Masson pine (Pinus massoniana) were both low. Overall, the emission potentials of the six species were too low (<200) to build up a sufficiently high NH3partial pressure in the leaves. Therefore, the Masson pine dominant subtropical forest at TSP acts as a sink for the atmospheric NH3, indicating that using the N flux in throughfall only may significantly underestimate the N income of the ecosystem. The results are informative for future modeling of plant-atmosphere NH3exchange and estimating N budget in local or regional scales.
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.|University of Chinese Academy of Sciences, Beijing, 100049, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Cui
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China. wangzhw@rcees.ac.cn.|University of Chinese Academy of Sciences, Beijing, 100049, China. wangzhw@rcees.ac.cn.
authors.forename: Zhangwei
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China.|University of Chinese Academy of Sciences, Beijing, 100049, China.
authors.forename: Xiaoshan
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Environmental Sciences, Norwegian University of Life Sciences, Postbox 5003, Ås 1430, Norway.
authors.forename: Jan
authors.initials: J
authors.lastname: Mulder
authors.affiliation: State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 100029, China.
authors.forename: Meigen
authors.initials: M
authors.lastname: Zhang
mesh_terms: D000641:Ammonia; D002681:China; D017753:Ecosystem; D065928:Forests; D009584:Nitrogen; D018515:Plant Leaves / Q000737:chemistry; D012987:Soil; D014197:Trees
chemical_list: D012987:Soil; D000641:Ammonia; D009584:Nitrogen
keywords: Ammonia; Emission potential; Nitrogen pool; Subtropical forests; Temporal variability