The cycle of matter in anaerobic environments

In anaerobic environments, provided that light can penetrate, distinctive microorganisms are able to maintain an almost completely closed anaerobic cycle of matter (Fig. 4.18). 

Mosley, J.W. In Transmission of Viruses by the Water Route. G. Berg (ed.). Intersience Publ., New York 1967, p. 5. 

Ainsworth, C.C. Dictionary of the Fungi, 6th ed. Commonwealth Mycological Institute, Kew 1971. 

Webster, J. Introduction to Fungi. Cambridge University Press, Cambridge 1970. 

Pojasek, R.A. Drinking Water Quality Enhancement through Source Protection. Ann Arbor Science Publishers, Ann Arbor 1977. 

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