LE3 .A278 2019

2019

Walker, Allison
López-Gutiérrez, Juan Carlos

Acadia University

Master of Science

Masters

Biology

Biology

Saltmarshes are ecosystems of significant ecological importance for their roles in coastal stability and fundamental roles in marine ecosystems. These ecosystems are in decline due to anthropogenic destruction and current climate regimes causing ocean level rise. Coastal restoration efforts are underway worldwide, but the success remains variable, with many failing in long term coastal stability. The fungal communities within saltmarsh sediment are understudied, especially in areas subject to mega-tidal influence such as the Bay of Fundy, Nova Scotia. My study investigates the fungi present in saltmarsh sediment and focuses on arbuscular mycorrhizal fungi (AMF); symbionts of the dominant saltmarsh grass Sporobolus pumilus (Roth) (Poaceae) (formerly Spartina patens). Internal transcribed spacer region 2 (ITS2)rDNA metaamplicon barcoding revealed many ubiquitous rhizosphere fungi, including AMF, in three saltmarsh sites around the Minas Basin, NS, but the persistent species composition may be based on the sediment characteristics. AMF colonization counts were conducted on S. pumilus roots and differed between the Kingsport saltmarsh and the Wolfville and Windsor saltmarshes, although the same Funneliformis species was found in all root tissue. Saltmarsh native AMF, Funneliformis geosporum, was propagated and used as a treatment for S. pumilus in three tidal mesocosm growth trials. This salt tolerant fungal symbiont increased host plant survival and growth under simulated saltmarsh conditions. These data indicate that fungal saltmarsh community establishment, especially AMF, are an essential consideration for improving saltmarsh restoration practices in areas of mega-tidal influence such as the Bay of Fundy.

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https://scholar.acadiau.ca/islandora/object/theses:3354