Contributo alla Conoscenza dell'idratazione e della Pressione Osmotica Nelle Specie di Tre Associazioni Forestali delle Marche: I° - L'idratazione

Abstract

Abstract Researches on the water content and osmotic pressure in plants of three forest associations in the Marche. I° - The water content. — The main forest associations of the Umbro-Marchigiani Appennines are the Orneto-Quercetum ilicis, the Quercetum pubescentis (s. l.) and the Fagetum. In each of these associations a typical station has been chosen where the most important species have been followed from March to November 1963 in order to determine the seasonal variations of their water content (« T.I. »)expressed as percentage of fresh weight. The annual curves show that the water content reaches very high levels in the early stages of plant development while it falls to lower levels later in the season when the leaves are full grown. The water content of each species follows a different course and can be considered a specific character. Taking into account the maximum and minimum levels of water content of the three groups of species a « hydric spectrum » has been worked out for the three associatio...