Effect of Habitat Modification on the Distribution of the Endangered Aquatic Fern Ceratopteris thalictroides (Parkeriaceae) in China

ABSTRACT

Progressive decline in natural populations of Ceratopteris thalictroides has resulted from the deterioration or complete loss of its primary habitat. We surveyed 22 tropical and subtropical areas in China where C. thalictroides occurred based on historical records and/or from observations during preliminary field surveys. Ten previously recorded populations have been extirpated, and human activity was identified as the most important cause of destruction and loss of the primary habitat of C. thalictroides. The distribution and occurrence of C. thalictroides were closely associated with water chemistry, with pH and conductivity being the most important factors.