Historical, ecological, taxonomic and health characterization of the relict elm stand of Rivas-Vaciamadrid (Madrid)

摘要

A series of studies focused on the characterization of an elm stand located at Rivas-Vaciamadrid (Comunidad de Madrid, Central Spain) are presented, revised and discussed. Since 2000, the elm stand history, its health, taxonomy, dendrochronology, and the reproductive and genetic characteristics of the elms have been analysed. The elm stand could have a partially anthropic origin, as indicated by the coexistence of Ulmus minor s.l. of Iberian origin with Ulmus minor var. vulgaris of Italian origin. The presence of cosexual and functionally-male trees indicates the existence of a gender differentiation. Functionally-male trees are numerically more frequent, but they have less genetic variability than the cosexual trees. A low but progressive decline during the second half of 20th century has been observed, probably as a consequence of Dutch elm disease. In order to help towards the elm stand conservation, some actions are proposed.