My Ph.D.dissertation research focused upon the San Francisco Bay where I studied the Holocene evolution of three estuarine marshes and related this to climatically forced changes in river flow and eustatic sea level rise (Goman and Wells, 2000; and Goman et al., 2004; Goman et al., 2008). A parallel theme within the dissertation was the development and statistical analysis of surface calibration data sets using a variety of analyses (grain size, loss-on-ignition, trace metal and macro fossil analysis) to serve as calibration proxies for salinity and tidal inundation (Goman, 2001 and 2005).
Strait of Juan de Fuca
Geoducks (Panope abrupta) are long-lived clams (100-160 years) that live in water depths from low intertidal to 100 meters depth and are found from southern California to Alaska; the clams lay down annual growth rings. This project was undertaken in collaboration with Lynn Ingram, my host during a yearlong visit to U.C. Berkeley. I analyzed growth rings from several clams for their oxygen and carbon isotopic signal, with the goal of reconstructing sea surface temperatures and upwelling for the historic period.
The purpose of this study was to initially reconstruct changes in vegetation through time for the region, so as to provide information on climate and paleoenvironmental change for archaeologists working at the Fort Bragg Military Base. I have two records from the base, one spanning the Holocene and the second a partial record encompassing the Last Glacial Maximum (LGM). The PAW site has an interesting record of Holocene climate change and suggests that the region was much wetter during the early Holocene than previous studies have shown and that this time period correlates with the possible northerly movement of the Bermuda High Pressure system (Goman and Leigh, 2004; 2006). This research was undertaken in conjunction with fluvial geomorphologist David Leigh (University of Georgia). The LGM record is interesting from a paleoecological perspective as it suggests that Picea (spruce) did not dominate the site throughout the late Pleistocene unlike other regions in the southeast (Goman, 2003).
Working with diatomist Sherri Cooper (Brynn Athyn College) I analyzed the pollen record from 2 cores from the Everglades Water Conservation District. The purpose of this research was to document broad scale environmental changes that have resulted because of historical human alterations to the natural flow of water in the region. In particular, Cladium (sawgrass) has been displaced by Typha (cattail) in part due to changes in water residency time but also due to changes in water alkalinity (Cooper et al., 2008).
My master's research focused on the pollen and microscopic charcoal record of Laguna Pompal, Veracruz. In this project I documented early agricultural activity and tropical forest clearance beginning about 5,000 years ago (Goman, and Byrne, 1998).