Accession Number : ADA119063

Title :   The Role of Mycorrhizal Fungi in Ecosystem Energetics.

Descriptive Note : Doctoral thesis,


Personal Author(s) : Biever,Lawrence Joseph

Full Text :

Report Date : Mar 1982

Pagination or Media Count : 172

Abstract : The vast majority of vascular plants in all nonhydric terrestrial ecosystems are mycorrhizal. While the effect of mycorrhizae on nutrition, survival and growth of plants (especially commercially important crops and trees) has been extensively investigated, little attention has been devoted to their role in the ecosystem as a whole. A review of the extensive literature has led me: (1) to conclude that energy flow through the mycorrhizal network represents a distinct and major food chain and (2) to test this hypothesis in a field study on experimental pine plantations. To obtain a minimum estimate of energy flow via the mycorrhizal path, sporocarps of Pisolithus tinctorium were harvested and annual production of woody tissue and needles measured in pine plantations on extremely poor soils at Copper Hill, Tennessee and at the Savannah River Plant, South Carolina. Addition of sporocarp production to tree growth increased the estimate of net primary production (NPP) by as much as 11%. Up to 10% of total NPP was estimated to pass through the sporocarps alone, an indication that total energy flow along this active extraction food chain can be quite large. The experiments, together with voluminous information in the literature, support the hypothesis that mycoorhizal fungi constitute a major energy flow pathway in terrestrial ecosystems.

Descriptors :   *Fungi , Ecosystems , Energetic properties , Energy transfer , Efficiency , Food chains , Plant growth , Production , Plants(Botany) , Theses

Subject Categories : Anatomy and Physiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE