The Effects of Experimental Manipulations of Substrata and Nutrients on a Colonizing Diatom Community

Abstract

This study examined the effects of nutrient level on diatom communities that colonized glass slides in artificial pools. These pools simulated gravel pit ponds with different substrate type. Following a three-week colonization period, 119 species of diatoms were identified from the pools. Early colonizers or r-selected species tended to dominate the experimental ponds. The diatom species Achnanthtes linearis and Amphora perpusilla were dominant in all ponds comprising from 40–90% of all specimens enumerated. Nearly half of the diatom species were found in only one pond, suggesting that a high degree of stochastic colonization is present for many species. A greater number of rare species were found when the pools were apparently N-limited.