Traspirazione e flusso di linfa xilematica in un ecosistema mediterraneo: confronto tra specie mediante trasduttori di flusso di linfa a bilancio termico ed eddy covariance

The vegetation of Mediterranean type ecosystem includes a large variety of plant life forms that have different strategies to withstand environmental stresses. Plant or stem sap flow has been used to understand these mechanisms (both down-scaling it to monitor leaf and stomatal responses and up-scaling it to entire stand). In complex natural vegetation where there are gaps in the canopy, plants of a range of size and a mixture of species, the relationship between ground area and sap flow is likely to vary with species and position in the canopy hierarchy. The best sampling method needs to be tailored to each ecosystem and plant stand. In this preliminary study we will examine the relationships between sap flow and plant characteristics in Mediterranean ecosystem and compare transpiration rates measured with 'heat balance' sap flow gauges to micro-meteorological techniques (eddy covariance). We will also compare the sap flow responses of three perennial woody species during a natural drying cycle.