Ideas and perspectives: on the emission of amines from terrestrial vegetation in the context of new atmospheric particle formation

Abstract

Abstract. In this article we summarise recent science which shows how airborne amines, specifically methylamines (MAs), play a key role in new atmospheric particle formation (NPF) by stabilising small molecule clusters. Agricultural emissions are assumed to constitute the most important MA source, but given the short atmospheric residence time of MAs, they can hardly have a direct impact on NPF events observed in remote regions. This leads us to the presentation of existing knowledge focussing on natural vegetationrelated MA sources. High MA contents as well as emissions by plants was already described in the 19th century. Strong MA emissions predominantly occur during flowering as part of a pollination strategy. The behaviour is species-specific, but examples of such species are common and widespread. In addition, vegetative plant tissue exhibiting high amounts of MAs might potentially lead to significant emissions. The decomposition of organic material constitutes another, potentially ubiquitous, source of airborne MAs. These mechanisms would provide sources, which could be crucial for the amine's role in NPF, especially in remote regions. Knowledge about vegetation-related amine emissions is, however, very limited, and thus it is also an open question how global change and the intensified cycling of reactive nitrogen over the last 200 years have altered amine emissions from vegetation with a corresponding effect on NPF.

Past, Present, and Future Atmospheric Nitrogen Deposition

“…Moreover, marine amines (ON) in the gas phase are here considered to form amine salts (ON in the particulate phase) consistent with the ON characterization by Altieri et al (2012) as predominantly containing reduced nitrogen. Amines of continental origin are not considered here because of the uncertainty and the weakness of their sources both of human and natural origin (Schade and Crutzen 1995;Ge et al 2011;Karl et al 2014;Sintermann and Neftel 2015). The organic nitrates that are of secondary origin and oxygenated inorganic nitrogen compounds both in the gas and particulate phases are explicitly calculated (Myriokefalitakis et al 2011).…”

The interaction between nitrogen and phosphorous is a strong predictor of intra-plant variation in nitrogen isotope composition in a desert species

“…Plants can emit a vast number of nitrogenous compounds to the atmosphere, which is known to affect atmospheric secondary aerosol formation and climate (Sintermann and Neftel, 2015). These compounds are formed in metabolic processes such as the decarboxylation and transamination of amino acids (Bagni and Tassoni, 2001;Dudareva et al, 2013).…”

“…However, it is a widely established fact that leaves exchange NH 3 with atmosphere through stomata Wetselaar and Farquhar, 1980;Farquhar et al, 1983;Sharpe and Harper, 1997;Johnson and Berry, 2013;Flechard et al, 2013;Sintermann and Neftel, 2015). So for the momentum, let us focus on leaves (Figs.…”

Fungal spores overwhelm biogenic organic aerosols in a midlatitudinal forest

“…Pollen could also contribute to OC because of its large size. Amines are another source of OC, but not well studied (Sintermann and Neftel, 2015). These sources from various sectors need to be further characterized for an unambiguous understanding of the sources of forest aerosols.…”

“…Certain PBAPs showed close correlations with atmospheric cloud condensation nucleus (CCN) and ice nucleus (IN) (Hiranuma et al, 2015;Huffman et al, 2013). However, simulations indicated that PBAPs are of regional importance for IN formation as they contribute very little to global average ice nucleation rates (Hoose et al, 2010;Spracklen and Heald, 2014). Unveiling PBAP mass concentrations is necessary to provide benchmarks for simulating its nucleation potentials and the effect on the climate.…”