The primary research focus of the Santa Barbara Coastal (SBC) LTER is on the relative importance of bottom-up processes and allochthonous inputs to giant kelp forests, a highly diverse and productive marine ecosystem that occurs on shallow rocky reefs at the interface of the land-ocean margin. Giant kelp forests are found along the temperate coasts of western North and South America, southern Africa, Australia and most sub Antarctic islands, including Tasmania and New Zealand. Because of their close proximity to shore, kelp forests are influenced by physical and biological processes that occur on land as well as in the open ocean. Integrative measurements, experiments, and modeling are being used by SBC investigators to determine how variability in subsidies and disturbance from terrestrial, atmospheric, and oceanic sources due to changing land use and climatic conditions affect the structure, dynamics, and function of giant kelp forest ecosystems. Effects of press and pulse environmental drivers on giant kelp forest ecosystems form the central focus of our current research, which is organized around three general themes (1) The influence of abiotic drivers on exchange rates of N and C between kelp forests and adjacent land and ocean habitats, (2) The direct and interactive effects of key drivers on kelp forest community structure and function through the modification of nutrient supply and wave disturbance, and (3) The indirect effects of these drivers on kelp forest community structure and function and the feedbacks between structure and function.