Collaborative research: Quantifying the biological,
chemical, and physical linkages between chemosynthetic
communities and the surrounding deep sea
This research will identify the form, extent and nature of the physical, chemical, and biological linkages between methane seeps and the surrounding deep-sea ecosystem on the Costa Rica margin using quantitative sampling and manipulative studies within a 3-dimensional oceanographic framework. We will examine the shape of the quantitative functions of diversity and density for organisms of different size classes and trophic position ranging from microbes to megafauna over the transition from the seep habitat through the ecotone to the background deep sea. Further, we will examine how depth, dissolved oxygen concentrations, pH and carbonate ion availability, relative rates of fluid flux, and substrate (biogenic, authigenic carbonate, sediments) alter these linkages and interactions with the deep sea. We will examine the evidence for distinct transitional communities, quantify patterns in density and alpha and beta diversity, and place these communities in a global biogeographic context. All of these investigations will take place across biological size spectra: for microorganisms (archaea, bacteria, microeukaryotes), macrofauna, the background fauna, and the larger animal size classes that form biogenic habitats. Our research results will be interpreted in the context of potential effects of climate change in the equatorial Pacific to determine how the linkages with the surrounding deep sea may change as anthropogenic impacts (including ocean acidification, warming, and deoxygenation) proceed in the future.