Leaf Size and Leaf Area Index in Fagus sylvatica Forests: Competing Effects of Precipitation, Temperature, and Nitrogen Availability

Abstract

Plants across diverse biomes tend to produce smaller leaves and a reduced total leaf area when exposed to drought. For mature trees of a single species, however, the leaf area-water supply relationship is not well understood. We tested the paradigm of leaf area reduction upon drought by a transect study with 14 mature Fagus sylvatica forests along a steep precipitation gradient (970-520 mm y )1 ) by applying two independent methods of leaf size determination. Contrary to expectation, average leaf size in dry stands (520-550 mm y )1 ) was about 40% larger and SLA was higher than in moist stands (910-970 mm y )1 ). As a result of increased leaf sizes, leaf area index significantly increased from the high-to the low-precipitation stands. Multiple regression analyses suggested that average leaf size was primarily controlled by temperature, whereas the influence of soil moisture and soil C/N ratio was low. Summer rainfall of the preceding year was the most significant predictor of total leaf number. We assume that leaf expansion of beech was independent of water supply, because it takes place in May with ample soil water reserves along the entire transect. In contrast, bud formation, which determines total leaf number, occurs in mid-summer, when droughts are severest. We conclude that leaf expansion and stand leaf area of beech along this precipitation gradient are not a simple function of water availability, but are controlled by several abiotic factors including spring temperature and possibly also nitrogen supply, which both tend to increase toward drier sites, thus overlaying any negative effect of water shortage on leaf development.

Is anticipated seed cutting an effective option to accelerate transition to high forest in European beech (Fagus sylvatica L.) coppice stands?

“…For example, leaf and total litter values for the unthinned plot were higher than those reported for various beech forests aged 47-200 years (Matteucci et al 1999), and for beech forests aged 83-147 years in France (Lebret et al 2001). In addition, leaf area index values were higher than those observed in other Italian beech forests (Cutini 2002), and agreed with those from other studies (Lebourgeois et al 2005;Meier and Leuschner 2008). This outcome is important because medium-high stand productivity (with reference to canopy attributes) represents one of the main requirements for improving forest management systems, particularly regarding the conversion of coppice woods.…”

“…Moreover, the use of ecological variables in our analyses allowed an objective and broadly comparable evaluation of the influence of the applied management options. The selected variables and experimental designs used were in accordance with that of other studies specifically addressing beech forest dynamics (e.g., Chianucci and Cutini 2013;Genet et al 2010;Lebourgeois et al 2005;Leuschner et al 2006;Meier and Leuschner 2008). Based on comparisons with these reports, we conclude that our studied stands are characterized by medium-high productivity, as revealed by the average values of canopy attributes.…”

Variation in leaf flushing date influences autumnal senescence and next year’s flushing date in two temperate tree species

“…Buds of oak and beech were formed in late summer, in line with previous studies (55,56). Leaf flushing observations were conducted on the terminal bud of each individual sapling, according to the following phenology scale: (1) undeveloped bud: bud still in winter dormancy; (2) swollen bud: green or elongated bud with broken scales; (3) leaf flushing: leaf bases still hidden in bud scales but leaf tips detached from the bud axis; and (4) leaf unfolded: the entire leaf blade and the leaf stalk were visible.…”

Raznolikost i strukturiranost hrvatskih kontinentalnih i alpsko-dinarskih populacija bijele johe (Alnus incana /L./ Moench subsp. incana); geografska i okolišna izolacija kao uzrok fenotipske divergencije

“…Similar results were also obtained by Meier and Leuschner (2008) for Fagus sylvatica stands in central Germany. Authors concluded that stand leaf area of the beech along this precipitation gradient is not a simple function of water availability, but is controlled by several abiotic factors including spring temperature and possibly also nitrogen supply, which both tend to increase toward drier sites, thus overlaying any negative effect of water shortage on leaf development.…”