The occurrence and distribution of actinomycetes in lakes of the English Lake District

Investigation of the occurrence of mesophilic actinomycetes in the lakes of the English Lake District revealed their widespread distribution in the lacustrine environment. Although only low numbers of actinomycetes occurred in the water, high numbers were recovered from all the lake muds. Total numbers of actinomycetes in the muds correlated quite well with the lakes’ productivity status. High numbers of Micro-monospora, Streptomyces and nocardioform actinomycetes were isolated from all the lakes sampled. Low numbers of Streptosporangium were isolated from all the muds but strains of Actinomadura, Actinoplanes, Dactylosporangium, Microbispora and Thermomonospora were only encountered occasionally. Micromonospora was the numerically dominant genus isolated from all the lakes sampled. This dominance was even more striking in deeper layers of mud and this was thought to reflect a more resistant spore stage in Micromonospora than in either of the other two main genera.