SPATIAL DISTRIBUTION OF ATTACHED ALGAE IN A SAND RIVER

Abstract

While the growth of attached algae is usually observed on gravel bed river, the large growth of them is sometimes seen even in sand rivers if river discharge is considerably small enough to provide the favorable habitat for attached algae. In the present study, field observations and numerical simulations were performed to know the growth of attached algae in a sand river. In the field observations, the growth of attached algae on fixed sand bed was measured weekly to identify the physiological characteristics of attached algae on sand surface. An integrated numerical simulation model is presented to describe the growth of attached algae on sand river, and the model can roughly predict the spatial distribution of attached algae. A series of numerical tests of growth of attached algae was performed under the various discharge conditions, and the effects of river discharge on growth of attached algae were discussed.