Table 1.
Main hypotheses that may contribute to explain contrasting growth responses to temperature in Iberian Angiosperm and Conifer trees on a large scale.
| Hypotheses | Angiosperms | Conifers | References |
|---|---|---|---|
| 1.1 Eco-physiological and hydraulic traits | Narrower hydraulic safety margins and higher capacity to reverse embolisms | Wide hydraulic safety margins, early drought-induced stomatal closure and lower carbon gain, low stomatal conductance sensitivity to VPD | Martínez-Ferri et al., 2000; Brodersen et al., 2010; Choat et al., 2012; Epron et al., 2012; Johnson et al., 2012; Michelot et al., 2012; Sala et al., 2012; Brodersen and McElrone, 2013; Coll et al., 2013; Meinzer et al., 2013; Ogasa et al., 2013 |
| 1.2 Phenology | Tree productivity more sensitive to growing season length | Positively affected but less sensitive to growing season length | Churkina et al., 2005; Piao et al., 2007; Welp et al., 2007; Delpierre et al., 2009; Richardson et al., 2010; Gómez-Aparicio et al., 2011; Coll et al., 2013 |
| 1.3 Intra- and inter-specific competition and forest succession | Growth less sensitive to intra and inter-specific stand competition | Growth severely reduced by intra- and inter-specific competence in small, non-dominant trees | Sánchez-Gómez et al., 2008; Gómez-Aparicio et al., 2011; Carnicer et al., 2013a; Coll et al., 2013; Vayreda et al., 2013 |
| 1.4 Size, age and allometry | Different growth allometry and less apical dominance | Peak of crown growth reached at lower sizes | Gómez-Aparicio et al., 2011; Poorter et al., 2012 |
| 1.5 Drought and temperature | Angiosperm trees are able to maintain substantial transpiration levels during summer drought events | Drought and heat waves often results in early stomatal closure in Mediterranean conifers | Martínez-Ferri et al., 2000; de Luis et al., 2007, 2011; Zweifel et al., 2007; Eilmann et al., 2009; Camarero et al., 2010; Klein et al., 2011; n, Coll et al., 2013; Poyatos et al., 2013 |
| 1.6 Winter freezing | Angiosperm trees are more vulnerable to freeze-thaw embolism | Less sensitive to freeze-thaw embolism | Sperry and Sullivan, 1992; Gómez-Aparicio et al., 2011; Brodribb et al., 2012 |
| 1.7 Interactions between multiple factors | Yes | Yes | Linares et al., 2010; Gómez-Aparicio et al., 2011; Vayreda et al., 2012; Coll et al., 2013; Ruiz-Benito et al., 2013 |
| 1.8 Local adaptation, individual and provenance variation | Yes | Yes | Rehfeldt, 1978, 1982; Santos et al., 2010; Ramírez-Valiente et al., 2010, 2011; Chmura et al., 2011; Robson et al., 2012; Alberto et al., 2013 |
| 1.9 Phenotypic plasticity | Yes | Yes | Camarero et al., 2010; Nicotra et al., 2010; de Luis et al., 2011 |