Little is known about the local to regional scale variability in biomass and productivity of many subtidal ecosystems as direct surveys for these habitats are often time and labor intensive. Here, we combined high-resolution satellite imagery with detailed diver sampling to assess changes in giant kelp (Macrocystis pyrifera) canopy cover and biomass along a ~60 km stretch coastline in the Santa Barbara Channel, California. Kelp canopy extent was determined by using principal component analysis on multispectral SPOT 5 satellite imagery.

 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.

This session is intended both for social and biophysical scientists who want to help develop a proposal for the kind of “multi-site, highly collaborative and integrated research initiative” envisioned by the LTER planning group. The focus will be on what the LTER planning process calls the “centerpiece” of the group's conceptual framework, as well as one of “Grand Challenges” to be addressed at the network level – “the dynamics of coupled human-natural ecosystems.”

Quantifying variability in nutrient transport is important for understanding the maintenance of coastal ecosystems. Understanding of the processes that control variability in nutrient transport off of Southern California is complicated by the very narrow continental shelf (2-5 km) in this region, which creates a more direct connection between shallow reefs and deeper oceanic waters. The Santa Barbara Channel (SBC) is one of these environments.

An aspect of climate change in California has been an increase in the intensity and frequency of winter storms. Disturbance from storms is a major source of variation in the standing biomass of the giant kelp Macrocystis pyrifera, a competitive dominant on shallow reefs that forms a dense overstory canopy at the sea surface. Climate induced changes in the standing biomass of Macrocystis are expected to have a profound effect on the assemblage of subordinate understory macroalgae.

 Most climate change research has concentrated on the direct effects of environmental change for individual species and their interactions. By affecting key foundation species and ecosystem engineers, however, climate change may have a variety of indirect that may complicate our abilities to predict the response of communities and ecosystems. In California, climate change has increased the frequency and intensity of storms over the last half century.  Storms may directly alter the structure of kelp forest food webs via disturbance.

Fish predation is an important disturbance affecting corals, yet few studies have compared the response of multiple coral species to one or more modes of fish predation. The present study differs from previous work on this topic by utilizing short-term field experiments, and testing the effects of corallivory on life stages (i.e., small or juvenile colonies) that are thought to be sensitive with regards to the effects of damage, and which play important roles in population growth.

Land uses and management practices in residential parcels (e.g., aesthetic/recreational/economic uses, land-cover choices, irrigation and chemical applications) impact and are impacted by social (e.g., stratification and status, environmental perceptions, zoning) and ecological (e.g., carbon sequestration, nutrient cycling, water demand and quality) processes.

Water motion has wide-ranging effects on scleractinians, particularly during thermal bleaching when increased flow may aid in resistance to high temperature. Increased flow removes photosynthetically-derived oxygen radicals, causing greater efficiency of PSII and conferring resistance to bleaching. However, enhanced flow can have both positive and negative effects on coral photophysiology (light-adapted yield, QY). Modest increases in flow benefit QY, while larger increases can have detrimental effects, suggesting that there is a threshold effect in QY along a flow continuum.

In the face of a changing global climate, being able to predict the response of organisms and to assess their vulnerability is essential for the development of successful management and conservations strategies. We hope to study the impacts of ocean acidification on two important members of the Moorea coral reef ecosystem: the sea urchin Echinometra mathaei and the coral Pocillopora damicornis.