HIV-1 specific IgA detected in vaginal secretions of HIV uninfected women participating in a microbicide trial in Southern Africa are primarily directed toward gp120 and gp140 specificities.

CAPRISA, 2014.Abstract available in pdf

Examination of Geospatial Patterns of Salt Marsh Dieback Development and Recover Using Historical Aerial Photography, Field Data, and Climatic Conditions

Presentation given at the Association of American Geographers Annual Meeting. Tidal marshes are one of the most valuable ecosystems on earth, as they provide habitats for various marine life species, protect shorelines, and improve water quality. Since 2001, Georgia salt marshes have experienced episodes of marsh death, termed dieback, in the dominant macrophyte, Spartina alterniflora. Previous studies suggested that climatic factors including temperature and precipitation pattern changes, sea level rise, drought severity, and changes in river discharge contributed to salt marsh dieback onset. Historical high resolution aerial imagery and field-based differential GPS (DGPS) were used to map changes in dieback extent over time. We collected aerial imagery between the years 1999 and 2017 and high resolution DGPS data from 2014 – 2018 for a dieback salt marsh near Saint Simons Island, Georgia. Dieback area was digitized in a GIS and rates of dieback growth and recovery were determined using the AMBUR package in R. Preliminary results showed that the site is currently undergoing a decline in dieback area (recovering), with numerous periods of growth and recovery from initial dieback onset to present. This study highlights the value of applying remote sensing techniques to monitor the changes in dieback, especially when historical field data are unavailable

Geospatial Patterns of Marsh Dieback Development and Recovery Using Aerial Photography, DGPS, and Climatic Conditions

Presentation given at the 25th Biennial CERF Conference

Response of stressed marsh following Hurricane Irma

Presentation given at the Georgia Water Resources Council. Salt marshes buffer developed coastal areas from storm surge produced by large storm events, like Hurricane Irma. Salt marshes have also been experiencing dieback events, leading to large mudflats, which erode, lose elevation, and impede marsh recovery. We have been monitoring vegetation, soil, groundwater, and dieback boundaries at a dieback site near St. Simons Island, GA, since 2014. The dieback was recovering before Hurricane Irma, which impacted the area in September 2017. Following the hurricane, once healthy Spartina alterniflora on the platform and upland boarder vegetation became stressed, most-likely from elevated salinities and storm surge flooding. New dieback along the creek bank also appeared. Periodic monitoring of the site in the months following the hurricane has shown that the upland boarder vegetation and new dieback along the creek bank have largely recovered. The existing dieback on the platform has continued to recover, however; the stressed S. alterniflora has remained stressed. Overall, we find that the marsh is generally resilient, with most areas of the marsh returning to pre-hurricane conditions within one year following the hurricane