Improved understanding of drought controls on seasonal variation in Mediterranean forest canopy CO2 and water fluxes through combined in situ measurements and ecosystem modelling

Water stress is a defining characteristic of Mediterranean ecosystems, and is likely to become more severe in the coming decades. Simulation models are key tools for making predictions, but our current understanding of how soil moisture controls ecosystem functioning is not sufficient to adequately constrain parameterisations. Canopy-scale flux data from four forest ecosystems with Mediterranean-type climates were used in order to analyse the physiological controls on carbon and water flues through the year. Significant non-stomatal limitations on photosynthesis were detected, along with lesser changes in the conductance-assimilation relationship. New model parameterisations were derived and implemented in two contrasting modelling approaches. The effectiveness of two models, one a dynamic global vegetation model ('ORCHIDEE'), and the other a forest growth model particularly developed for Mediterranean simulations ('GOTILWA+'), was assessed and modelled canopy responses to seasonal changes in soil moisture were analysed in comparison with in situ flux measurements. In contrast to commonly held assumptions, we find that changing the ratio of conductance to assimilation under natural, seasonally-developing, soil moisture stress is not sufficient to reproduce forest canopy CO2 and water fluxes. However, accurate predictions of both CO2 and water fluxes under all soil moisture levels encountered in the field are obtained if photosynthetic capacity is assumed to vary with soil moisture. This new parameterisation has important consequences for simulated responses of carbon and water fluxes to seasonal soil moisture stress, and should greatly improve our ability to anticipate future impacts of climate changes on the functioning of ecosystems in Mediterranean-type climates.

Developmental Readiness in the Understanding of Own and Other’s False Beliefs

One of the most important milestones in the development of theory of mind is the understanding of false beliefs. This study compares children’s understanding of representational change and others’ false beliefs and evaluates the effectiveness of an appearance-reality training for improving children’s false belief understanding. A total of 78 children ranging in age from 41 to 47 months were trained in three sessions and evaluated in a pretest and in a posttest. The results show that for children it is easier to understand representational change than false beliefs in others, and that the improvement after training was greater when starting from a higher score in the pretest. The implications of this for training in false belief understanding are discussed

Children's understanding of pretend emotions

This preliminary study aims to investigate children’s ability to understand that the emotional expressions that occur in pretend play do not necessarily coincide with the emotions people feel inside. Previous research has found that children aged 4 and 6 have difficulty to distinguish between the external and the internal emotion of a character who pretends an emotion. In the present work, thirteen 4-year-olds and eight 6-year-olds were administered stories in which a character simulated an emotion. Differently from previous research, the questions addressed to the children did not focus on the distinction external/internal emotion but on the distinction between real/pretend emotion. Furthermore, since previous research has suggested that children may understand better selfpretence than pretence of others, the participants in our study were engaged in a pretence situation where they had to pretend to be happy. The results obtained showed that, contrary to previous research, most 4- and 6-year-olds realize that pretend emotions may not be real, and this was true both for self-pretence and for the pretence of others