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Effects of light and temperature on isoprene emission at different leaf develop...
Alves, Eliane Gomes; Harley, Peter C.; Gonçalves, José Francisco Carvalho de; Silva, Carlos Eduardo Moura da; Jardine, Kolby J.Isoprene emission from plants accounts for about one third of annual global volatile organic compound emissions. The largest source of isoprene for the global atmosphere is the Amazon Basin. This study aimed to identify and quantify the isoprene emission and photosynthesis at different levels of light intensity and leaf temperature, in three phenological phases (young mature leaf, old mature leaf and senescent ...
Leaf phenology as one important driver of seasonal changes in isoprene emission...
Alves, Eliane Gomes; Tóta, Júlio; Turnipseed, Andrew A.; Guenther, Alex B.; Vega Bustillos, José Oscar W.; Santana, Raoni Aquino Silva deIsoprene fluxes vary seasonally with changes in environmental factors (e.g., solar radiation and temperature) and biological factors (e.g., leaf phenology). However, our understanding of the seasonal patterns of isoprene fluxes and the associated mechanistic controls is still limited, especially in Amazonian evergreen forests. In this paper, we aim to connect intensive, field-based measurements of canopy isopre...
Seasonality of isoprenoid emissions from a primary rainforest in central Amazonia
Alves, Eliane Gomes; Jardine, Kolby J.; Tóta, Júlio; Jardine, Angela B.; Yáñez-Serrano, Ana Maria; Karl, Thomas G.; Tavares, Julia ValentimTropical rainforests are an important source of isoprenoid and other volatile organic compound (VOC) emissions to the atmosphere. The seasonal variation of these compounds is however still poorly understood. In this study, vertical profiles of mixing ratios of isoprene, total monoterpenes and total sesquiterpenes, were measured within and above the canopy, in a primary rainforest in central Amazonia, using a pr...
Airborne observations reveal elevational gradient in tropical forest isoprene e...
Gu, Dasa; Guenther, Alex B.; Shilling, John E.; Yu, Haofei; Huang, Maoyi; Zhao, Chun; Yang, Qing; Martin, Scot T.; Artaxo, Paulo; Kim, SaewungIsoprene dominates global non-methane volatile organic compound emissions, and impacts tropospheric chemistry by influencing oxidants and aerosols. Isoprene emission rates vary over several orders of magnitude for different plants, and characterizing this immense biological chemodiversity is a challenge for estimating isoprene emission from tropical forests. Here we present the isoprene emission estimates from ...
Dynamic balancing of isoprene carbon sources reflects photosynthetic and photor...
Jardine, Kolby J.; Chambers, Jeffrey Quintin; Alves, Eliane Gomes; Teixeira, Andrea; Garcia, Sabrina; Holm, Jennifer A.; Higuchi, NiroThe volatile gas isoprene is emitted in teragrams per annum quantities from the terrestrial biosphere and exerts a large effect on atmospheric chemistry. Isoprene is made primarily from recently fixed photosynthate; however, alternate carbon sources play an important role, particularly when photosynthate is limiting. We examined the relative contribution of these alternate carbon sources under changes in light ...
Monoterpene chemical speciation in a tropical rainforest:variation with season,...
Yáñez-Serrano, Ana Maria; Nölscher, Anke C.; Bourtsoukidis, Efstratios; Alves, Eliane Gomes; Ganzeveld, Laurens N.; Bonn, Boris; Wolff, StefanSpeciated monoterpene measurements in rainforest air are scarce, but they are essential for understanding the contribution of these compounds to the overall reactivity of volatile organic compound (VOC) emissions towards the main atmospheric oxidants, such as hydroxyl radicals (OH), ozone (O3) and nitrate radicals (NO3). In this study, we present the chemical speciation of gas-phase monoterpenes measured in the...
Urban pollution greatly enhances formation of natural aerosols over the Amazon ...
Shrivastava, Manish K.; Andreae, Meinrat O.; Artaxo, Paulo; Barbosa, H. M. J.; Berg, Larry K.; Brito, Joel F.; Ching, Joseph; Easter, Richard C.One of the least understood aspects in atmospheric chemistry is how urban emissions influence the formation of natural organic aerosols, which affect Earth’s energy budget. The Amazon rainforest, during its wet season, is one of the few remaining places on Earth where atmospheric chemistry transitions between preindustrial and urban-influenced conditions. Here, we integrate insights from several laboratory meas...
Diel and seasonal changes of biogenic volatile organic compounds within and abo...
Yáñez-Serrano, Ana Maria; Nölscher, Anke C.; Williams, Jonathan C.; Wolff, Stefan; Alves, Eliane Gomes; Martins, Giordane AugustoThe Amazonian rainforest is a large tropical ecosystem, which is one of the last pristine continental terrains. This ecosystem is ideally located for the study of diel and seasonal behaviour of biogenic volatile organic compounds (BVOCs) in the absence of local human interference. In this study, we report the first atmospheric BVOC measurements at the Amazonian Tall Tower Observatory (ATTO) site, located in cen...
Emissions of putative isoprene oxidation products from mango branches under abi...
Jardine, Kolby J.; Meyers, Kimberly T.; Abrell, Leif; Alves, Eliane Gomes; Yáñez-Serrano, Ana Maria; Kesselmeier, Jürgen; Karl, Thomas G.Although several per cent of net carbon assimilation can be re-released as isoprene emissions to the atmosphere by many tropical plants, much uncertainty remains regarding its biological significance. In a previous study, we detected emissions of isoprene and its oxidation products methyl vinyl ketone (MVK) and methacrolein (MACR) from tropical plants under high temperature/light stress, suggesting that isopren...