Establecimiento de cuatro especies de Quercus en el sur de la ...

Capítulo 5
Lamhamedi et al., 1998). In fact, stomatal conductance reflects the water use strategy
of plants; thus, stomatal closure avoids excessive transpiration and xylem cavitation
(Cochard et al., 1996), but can compromise photosynthesis and reduce the growth
potential of plants as a result (Larcher, 1995). Because seedlings must develop long
roots rapidly enough to compete with the herbaceous layer and access deeper water
soil profiles during the dry season, adopting a spender strategy in order to facilitate
growth may be more successful at an early development stage (Bragg et al., 1993).
In summary, the choice of a particular afforestation method is dictated by a
number of factors including site conditions, seedling quality and water status, the
particular species to be regenerated and the specific objectives of the restoration
project (Dey et al., 2008). Identifying the best possible choice in each case usually
entails assessing various methods under different conditions, and examining the
morphological and physiological processes that underlie seedling outplanting
performance. No previous simultaneous assessment of direct seeding and planting of
1‐ and 3‐year‐old seedling with Q. ilex and Q. suber oaks has to the authors’ knowledge
been done. The primary purposes of this work were thus as follows: (a) to compare
direct seeding with planting of 1‐ and 3‐year‐old seedlings of the two most common
oak species in the Iberian Peninsula; (b) to confirm whether morphological or
physiological attributes can be used to explain seedling performance in the field; (c)
and to identify the most suitable afforestation method for the two species.
MATERIAL AND METHODS
Site description
The study was carried out in an experimental plot at the University of Córdoba
(Campus de Rabanales, Córdoba, Spain, 37°51’N, 4°48’W, 100 m a.s.l.) that was
formerly used as agricultural land. The site has a small slope (< 2%) and the soil is a
fluvisol consisting of heterometric silical gravels containing occasional calcareous
boulders (Table 1).
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