The Antarctic represents the last of the world's still unexplored continents. Since 1985, Italy has sent 10 expeditions to this region, three of those have been exclusively devoted to research on the marine ecology of the Ross Sea region. This volume presents a global picture of this research. It includes contributions on water mass characteristics, particulate organic matter and nutrient utilization, and physiological aspects of primary production. Further topics are zooplankton, krill and top predator interactions in relation to physical and biological parameters, ecological features of coastal fish communities and the spatio-temporal variability of benthic biocenoses.

This dissertation examines several aspects of the unique physical-biological system that controls biogeochemical cycling in the Ross Sea, the largest continental shelf sea along the Antarctic margin and the most biologically productive region in the Southern Ocean. The core component of the research involves interpretation of data from two oceanographic cruises to the region, one during Summer of 2005--2006 and another in Spring of 2006--2007. Four key research questions are addressed. (1) What physical mechanisms force spatial and temporal variability in mixing depths? (2) How does the dynamic physical environment characteristic of Antarctic continental shelf seas structure distributions of biomass and chemical tracers of production? (3) What key physical and physiological mechanisms control the 13C/12C ratio of organic and inorganic carbon in waters on the Ross Sea continental shelf? and (4) How do physiological variables interact with environmental variability to control phytoplankton taxonomic zonation? Chapter 1 presents an introduction to ocean carbon biogeochemistry and the oceanography of the Southern Ocean and the Ross Sea. Chapter 2 examines the mechanisms effecting early season stratification in the Ross Sea. Lateral advection in the region of upper ocean fronts is shown to be an important mechanism setting early season stratification. Chapter 3 examines several tracer-based methods for estimating upper ocean net community production in the Ross Sea, with explicit recognition of the complexities associated with control volume assumptions and high rates of temporal change. Chapter 4 considers the environmental controls on the distribution of 13C/12C ratios in the Ross Sea. It is shown quantitatively that the two dominant phytoplankton taxa in the Ross Sea have different intrinsic fractionation factors, likely as a result of differing carbon-acquisition physiologies. Air-sea exchange is shown to occur with very noisy fractionation. Finally, Chapter 5 examines the interaction of algal physiology with environmental variability, addressing the key physiological-environmental controls on the taxonomic distribution of phytoplankton in the Ross Sea. While it is difficult to draw concrete conclusions, the most compelling line of evidence suggests that differing photoprotective capacities is the most important physiological characteristic structuring taxonomic distributions. An appendix presents a design for an infrared absorbance-based instrument for the determination of total dissolved inorganic carbon in seawater.

A stunning collection of oceanic photography documenting the world’s last pristine ocean. Due to its remoteness and harsh weather, Antarctica’s Ross Sea remained free from human interference until 1996, when commercial fishing discovered it. Now that fishery removes 3,000 tons of fish annually, threatening to destroy the world’s last intact ecosystem. The Last Ocean organization started in 2004, joining scientists and environmental groups in a campaign to have the entire Ross Sea designated as an international marine protected area. One of the founding members of The Last Ocean is John Weller, whose photographs from the Ross Sea were collected during four trips to the Antarctic, including a four-month stay at McMurdo and Cape Royds, home of the southernmost penguin colony in the world. Offering a rare glimpse into life at the edge of the world—from Emperor and Adélie penguins to silverfish, seals, and minke whales—Weller takes the reader on an unprecedented journey above and below the ocean surface. The Last Ocean is more than stunningly beautiful photography. It is a story central to our own: our struggle to sustain a population in a changing climate and with exponentially increasing pressures on world resources.