Marine fungal diversity: a comparison of natural and created salt marshes of the north-central Gulf of Mexico

Abstract

Marine fungal communities of created salt marshes of differing ages were compared with those of two reference natural salt marshes. Marine fungi occurring on the lower 30 cm of salt marsh plants Spartina alterniflora and Juncus roemerianus were inventoried with morphological and molecular methods (ITS T-RFLP analysis) to determine fungal species richness, relative frequency of occurrence and ascomata density. The resulting profiles revealed similar fungal communities in natural salt marshes and created salt marshes 3 y old and older with a 1.5 y old created marsh showing less fungal colonization. A 26 y old created salt marsh consistently exhibited the highest fungal species richness. Ascomata density of the dominant fungal species on each host was significantly higher in natural marshes than in created marshes at all three sampling dates. This study indicates marine fungal saprotroph communities are present in these manmade coastal salt marshes as early as 1 y after marsh creation. The lower regions of both plant hosts were dominated by a small number of marine ascomycete species consistent with those species previously reported from salt marshes of the East Coast of USA.

• ITS T-RFLP analysis
• Juncus roemerianus
• salt marsh fungi
• Spartina alterniflora

The authors thank the faculty, staff and students of the University of Southern Mississippi’s Gulf Coast Research Laboratory, the staff of the Grand Bay National Estuarine Research Reserve for field assistance, A. Rossman and H. Raja for literature, and C. Park for technical assistance. Financial support from the Mississippi-Alabama Sea Grant Consortium (MASGC Grant No. R/CEH-25), the Mississippi Department of Marine Resources Tidelands Trust Fund Program (Tide-lands 05-002/FY004-M0204-2) and the University of Southern Mississippi (Thesis Research Grant and Lytle Coastal Sciences Scholarship to AKW) is gratefully acknowledged.