Current status and conservation of the Lusitan Duriensean Orchids (Duero Basin, NE Portugal and CW Spain)

摘要: Twenty eight orchids species and subspecies are presently recognised as indigenous in the Lusitan Duriensean biogeographical sector, which covers part of Duero Basin Portugal Spain. one these (75%) rare or very this sector under threat from different agents. This paper provides a detailed study their distribution estimates sizes populations. The latter were based on our own census data, collected at sites where found. All potentially reproductive individuals counted. causes rarity factors responsible for regression that still affects many analysed; main threats destruction woods by human activities overgrazing. These data may be use to nature conservation authorities