Living under water for up to four months of the year: observations on the rheophytes of
the Mekong River in the Pha Taem National Park area (Thailand/Laos border)
Abstract
Rheophytes of the Mekong were investigated in the Pha Taem National Park area (Thailand/Laos border); a stretch of river ca. 100 km long was studied. The unusually harsh environmental conditions (water levels changing by several meters; plants submerged for up to four months per year) are described, and general characteristics and adaptations of these “extreme rheophytes” are elaborated on. The kinds of rheophyte habitats are characterized. A list of observed rheophytes (25 taxa) is provided and comments are made on their distribution patterns both in the study area and elsewhere. A comparison with “Siphandone Wetlands”, a well studied area of the Mekong in southern Laos, is included.
Key words: Mekong, rheophytes; Pha Taem National Park, Thailand/Laos border.
