Ecophysiology of selected tree species in different plant communities at the periphery of the Atlantic Forest of SE-Brazil. III. Three legume trees in a semi-deciduous dry forest

• Published in: Trees (Berlin, West) Vol. 19; no. 5; pp. 523 - 530
• Main Authors: Gessler, A, Duarte, H.M, Franco, A.C, Luttge, U, Mattos, E.A. de, Nahm, M, Rodrigues, P.J.F.P, Scarano, F.R, Rennenberg, H
• Format: Journal Article
• Language: English
• Published: Berlin Springer 01.09.2005; Springer Nature B.V
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Biological and medical sciences; Caesalpinia echinata; Caesalpinia ferrea; carbon; coastal forests; dry environmental conditions; environmental factors; Fabaceae; forest ecology; forest ecosystems; Fundamental and applied biological sciences. Psychology; Machaerium obovatum; niches; nitrogen compounds; nitrogen metabolism; phloem; photoinhibition; Photosynthesis; photosynthetic capacity; plant physiology; sap; stable isotopes; sugars; Synecology; Terrestrial ecosystems; trees; Brazil; Machaerium; Forests; Plant community; Phylogeny; Metabolism; Caesalpinia; N-metabolism; Phloem; Photosystem; Stable carbon isotope ratios; Leguminosae; Geographic distribution; Dicotyledones; Angiospermae; Ecological niche; Photoinhibition; Spermatophyta; Phloem-sap; Photosynthesis; Ecophysiological niche
• ISSN: 0931-1890; 1432-2285
• DOI: 10.1007/s00468-005-0423-6

Three legume tree species (Fabaceae) occurring abundantly in a semi-deciduous tropical dry forest of the Atlantic forest complex in southeastern Brazil were subjected to a comparative ecophysiological study at the end of the dry season/beginning of the wet season. The trees chosen were morphologically very similar: Caesalpinia echinata Lam. and Caesalpinia ferrea Mart. ex. Tul., both 10-20 m of height, of the sub-family Caesalpinioideae, and the somewhat smaller, 2-4 m tall, Machaerium obovatum Kuhlm. & Hoehne of the sub-family Faboideae. Despite their similarities with respect to their geographic distribution restricted to Brazilian dry forests, their comparable abundance in the study site and their phylogenetic proximity, the three species display distinctly different ecophysiological behaviour. Compared to the other two species, C. ferrea had the highest photosynthetic capacity (maximum apparent photosynthetic electron transport rate, ETR^sub max^) and higher saturation light-intensity, was less subject to photoinhibition as indicated by potential quantum yield of photosystem II (F^sub v^/F^sub m^) and had the lowest bulk N content of which soluble non-protein N compounds were only 1.5%. It showed stronger sun plant characteristics. C. echinata had lower photosynthetic capacity, was under chronic photoinhibition and had high bulk N content of which 6.1% were soluble N compounds with high concentrations of proline. In addition to proline, high concentrations of sugars may serve as osmoprotectants. M. obovatum also showed lower photosynthetic capacity and was under chronic photoinhibition. Here, arginine may have a function as osmoprotectant. The ecophysiological differences between the three species are not related to local abundance. However, the observations presented highlight a contrasting behaviour of the otherwise very similar compatriot species.[PUBLICATION ABSTRACT]