Rainfall variation and marsh plants Dr. Steven C. Pennings University of Houston

Department of Biology and Biochemistry University of Houston Houston Texas 77204-5513 USA

scpennin@central.uh.edu https://uh.edu/nsm/biology-biochemistry/people/profiles/steven-pennings/ https://orcid.org/0000-0003-4757-7125 Georgia Coastal Ecosystems LTER Project

Dept. of Marine Sciences University of Georgia Athens Georgia 30602-3636 USA

gcelter@uga.edu https://gce-lter.marsci.uga.edu/ Dr. Steven C. Pennings University of Houston

Department of Biology and Biochemistry University of Houston Houston Texas 77204-5513 USA

scpennin@central.uh.edu https://uh.edu/nsm/biology-biochemistry/people/profiles/steven-pennings/ https://orcid.org/0000-0003-4757-7125 Principal investigator 2026

Pennings (UH) is testing the hypothesis that annual variation in high-marsh plant species composition is driven by variation in rainfall. Salt marsh vegetation often consists of discrete stands with abrupt borders between different species or associations. Pennings has monitored mid-summer plant composition at permanent plots located on 3 types of vegetation borders (Spartina alterniflora-Juncus roemerianus, S. alterniflora-meadow, meadow-Juncus roemerianus), at two sites each, since 1996. Vegetation composition in these plots is dynamic and appears to be related to variation in rainfall, although again more years of data will be needed to test this hypothesis rigorously.

Area 2: Patterns within the Domain (more information) Question 2: How do the spatial and temporal patterns of biogeochemical processes, primary production, community dynamics, decomposition, and disturbance vary across the estuarine landscape, and how do they relate to environmental gradients? (more information)

rainfall LTER NSF Georiga GCE Juncus Spartina salt marsh vegetation Overall geographic extent of the research project -81.297445 -81.289170 31.418899 31.400830 1996-01-01

National Science Foundation grant numbers OCE-9982133 and OCE-0620959

estuary marsh complex Marsh Landing - Marsh landing, where the Georgia DNR ferry docks on its route between the mainland (Meridian) and Sapelo Island. -81.297445 -81.294606 31.418899 31.416399 Shell_Hammock - Shell_Hammock sampling site used by Amy Kunza in 2005 to study plant species richness -81.289170 -81.289170 31.400830 31.400830 Pennings, S.C., Bertness, M.D., Donnelly, J.P., Ewanchuk, P.J., Silliman, B.R. and Callaway, R.M. 2001. Presentation: Impacts of global change on coastal salt marshes. Keynote address to the German Limnological Association, September 17-21, 2001, Kiel, Germany.