Structural differences between cerrado species with different leaf phenologies are linked to crown architecture, leaf production, and biomass allocation to shoots and leaves. The present study characterized crown structures and the patterns of biomass allocation to leaves and shoots in two woody cerrado species with contrasting leaf phenologies and quantified the irradiance reaching their leaves to determine the best period during the day for photosynthetic activity. The shoots and leaves of five individuals of both Annona coriacea (deciduous) and Hymenaea stigonocarpa (evergreen) were collected along a 50 m transect in a cerrado fragment within the urban perimeter of Catalão - GO, to determine their patterns of biomass allocation in their crowns. The evergreen H. stigonocarpa had significantly higher mean values of shoot inclination (SI), petiole length (PL), leaf area (LA), leaf display index (LDI), and individual leaf area per shoot (ILA), while the deciduous species A. coriacea had significantly higher leaf numbers (LN). The more complex crown of H. stigonocarpa had shoots in more erect positions (orthotropic), with intense self-shading within shoots; A. coriacea, on the other hand, had slanting (plagiotropic) shoots in the crown, allowing similar irradiance levels to all leaf surfaces. The production of plagiotropic shoots by the deciduous species (A. coriacea) is a strategy that enables its use of incident sunlight early in the morning and preventing excessive water loss or excessive irradiance. Hymenaea stigonocarpa (an evergreen), by contrast, had orthotropic shoots and uses intense self-shading as a strategy to avoid excessive irradiance, especially at midday. Differences in crown architectures between evergreen and deciduous species of cerrado sensu stricto can therefore be viewed as adaptations to the environmental light regime.

The post-summer leaf demography of the wintergreen species Aristotelia chilensis growing near San Carlos de Bariloche, Argentina, is described. Its specific leaf mass (SLM, g m-2) is compared to that of the deciduous and evergreen species of the Andean-Patagonian forests and to that of other communities abroad. The pattern of leaf emergence is intermediate, with leaf flush in spring (basal cohort, BC), followed by successive unfolding of the remaining leaves (distal cohort, DC) during summer. The senescence of the BC occurs mainly in autumn, with a loss of 11-31 % of its SLM. The DC falls synchronously in mid-spring and the SLM loss in winter is 10-13 %. The SLM of A. chilensis (103.6 ± 6.2 g m-2) is intermediate when compared to the general mean values of deciduous (73.7 ± 15.9 g m-2) and evergreen species (154.8 ± 45.8 g m-2). The SLM of deciduous and evergreen species of three different forests near San Carlos de Bariloche varied significantly at the end of the growing season while that of A. chilensis showed more constant values. The periodicity of leaf production and senescence in A. chilensis allows the maintenance of one leaf cohort throughout the year, covering the carbon demand for flowering and leaf production in spring. This differentiates the deciduous from the wintergreen species, despite their similar mean leaf life span values, while the evergreen species have a longer leaf turnover. Considering the conditions for growth in each studied forest, the leaf life span was not the only factor determining the SLM value. This variable would also depend on multiple stresses that may act during the ontogenesis and evolution of the leaves in each phenological group

Se describe la demografía foliar después del verano de la especie invierno-verde Aristotelia chilensis, creciendo cerca de la ciudad de San Carlos de Bariloche, Argentina. Se compara su peso específico foliar (SLM, g m-2) con los valores de especies deciduas y siempreverdes de los bosques andino-patagónicos y de comunidades de otras regiones. El patrón de emergencia foliar es intermedio, con un pulso de hojas en primavera (cohorte basal, BC) seguido por la emergencia en forma sucesiva de las restantes hojas (cohorte distal, DC) durante el verano. La senescencia de BC ocurre principalmente en el otoño, con una pérdida de 11-31 % de su SLM. La DC cae sincrónicamente a mediados de primavera y su pérdida de SLM en el invierno es de 10-13 %. El SLM de A. chilensis (103.6 ± 6,2 g m-2) es intermedio cuando se compara con los valores medios generales de especies deciduas (73,7 ± 15,9 g m-2) y siempreverdes (154,8 ± 45,8 g m-2). El SLM de las especies deciduas y siempreverdes pertenecientes a tres diferentes bosques cercanos a San Carlos de Bariloche varió significativamente al final de la estación de crecimiento, mientras que A. chilensis mostró valores más constantes. La periodicidad en la producción y senescencia de las hojas en A. chilensis permite el mantenimiento de una cohorte foliar a través del año, cubriendo la demanda de carbono para la floración y la producción de hojas en primavera. Esto distingue a las especies invierno-verdes de las deciduas a pesar de sus similares tiempos promedio de vida de la hoja, mientras que las especies siempreverdes tienen un ciclo de reemplazo foliar más largo. Tomando en consideración las condiciones de crecimiento en cada uno de los bosques estudiados, el tiempo de vida de la hoja no fue el único factor que determinó el valor de SLM de las especies. Esta variable también dependería de múltiples estreses, que pueden actuar durante la ontogénesis y la evolución de la hoja en cada grupo fenológico