HABITAT CONDITIONS ON VALLISNERIA HIGOENSIS AS ENDANGERED SPECIES

Abstract

The comprehension of the diversity and ecological nature of native aquatic plants is fundamental necessity for conservation of healthy river environment. Vallisneria higoensis is endemic to Kumamoto Prefecture, Japan. Although it is designated as a vulnerable species in the Japanese edition of the Red Data Book, little is known about its distributions or habitat.

In this paper, field surveys have been completed to clarify the reason of the exclusion or the factors that determine abiotic tolerance and biotic interactions on Vallisneria higoensis. The results showed that Vallisneria higoensis has been invaded by alien Canadian waterweed but survived in relatively shallow, fast flow field and sand bed.