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Age-dependent leaf physiology and consequences for crown-scale carbon uptake du...
Albert, Loren P.; Wu, Jin; Prohaska, Neill; Camargo, Plínio Barbosa de; Huxman, Travis E.; Tribuzy, Edgard Siza; Ivanov, Valeriy Yu; Oliveira, Rafael S.Satellite and tower-based metrics of forest-scale photosynthesis generally increase with dry season progression across central Amazônia, but the underlying mechanisms lack consensus. We conducted demographic surveys of leaf age composition, and measured the age dependence of leaf physiology in broadleaf canopy trees of abundant species at a central eastern Amazon site. Using a novel leaf-to-branch scaling appro...
Highly reactive light-dependent monoterpenes in the Amazon
Jardine, Angela B.; Jardine, Kolby J.; Fuentes, José D.; Martin, Scot T.; Martins, Giordane Augusto; Durgante, Flávia MachadoDespite orders of magnitude difference in atmospheric reactivity and great diversity in biological functioning, little is known about monoterpene speciation in tropical forests. Here we report vertically resolved ambient air mixing ratios for 12 monoterpenes in a central Amazon rainforest including observations of the highly reactive cis-β-ocimene (160 ppt), trans-β-ocimene (79 ppt), and terpinolene (32 ppt) wh...
Cd-tolerance markers of Pfaffia glomerata (Spreng.) Pedersen plants: Anatomical...
Pedrosa Gomes, Marcelo; Marques, Teresa Cristina Lara Lanza Sá Sáe Melo; Martins, Giordane Augusto; Carneiro, Marília Mércia Lima CarvalhoPhysiological and anatomical features of Cd-tolerance in Pfaffia glomerata were examined by exposing plantlets to nutrient solutions with increasing Cd concentrations (0, 15, 45, and 90 μmol Cd L-1), and possible Cd-tolerance markers were established. Cd contents were found to be higher in roots than in shoots. According to the bio-concentration factor data, this species is effectively a Cd-hyperaccumulator, as...
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...
Convergence in relationships between leaf traits, spectra and age across divers...
Wu, Jin; Chavana-Bryant, Cecilia; Prohaska, Neill; Serbin, Shawn P.; Guan, Kaiyu; Albert, Loren P.; Yang, Xi; Van Leeuwen, Willem Jan DirkLeaf age structures the phenology and development of plants, as well as the evolution of leaf traits over life histories. However, a general method for efficiently estimating leaf age across forests and canopy environments is lacking. Here, we explored the potential for a statistical model, previously developed for Peruvian sunlit leaves, to consistently predict leaf ages from leaf reflectance spectra across tw...
Plant physiological ecology and the global changes
Barbosa, J. P.R.A.D.; Rambal, Serge; Soares, Ângela Maria; Mouillot, Florent; Nogueira, Joana Messias Pereira; Martins, Giordane AugustoThe global changes are marked by alteration on the normal patterns of important biochemical and biophysical processes of the Earth. However, the real effects as well as the feedbacks of the global changes over vegetation are still unclear. Part of this uncertainty can be attributed to the inattention of stakeholders and scientists towards vegetation and its complex interrelations with the environment, which dri...
Estimating the IAF of coffee from the volume occupied by leaves and plant archi...
Barbosa, João Paulo Rodrigues Alves Delfino; Martins, Giordane Augusto; Ferreira, Rafael Teixeira; Pennacchi, João Paulo; Souza, Vinícius Fernandes deThe methods used for estimating the leaf area index (LAI) of coffee (Coffea arabica L.) show limitations related to therepresentation of some aspects of coffee crops, affecting the LAI in time and space. This work was developed to propose a method forassessing the LAI of coffee aiming to reduce those limitations. We studied plants in the production phase of the Mundo Novo and Catuaívarieties, in plantations loc...