Macroalgae and phytoplankton support highly productive coastal marine ecosystems. Research based on stable isotope analyses has supported the idea that macroalgal detritus, especially that of giant kelp Macrocystis, is a major source of dietary carbon to benthic suspension feeders.

Seagrass meadows are declining worldwide as a result of nutrient over-enrichment, warming water temperatures, and anthropogenic disturbances. In many areas, restoration projects are attempting to the reverse the trend with varying success. In the Virginia coastal lagoons, seagrasses (Zostera marina) were lost in the 1930’s due to a large hurricane impacting meadows already weakened by the wasting disease. A large-scale restoration effort has been underway since the early 2000’s and has resulted in >1000 acres of seagrass coverage.

The southern California Current System (CCS) is a moderate upwelling system comprised of water masses with differing nutrient loadings and consequently community structure. The mesozooplankton community of the CCS is dominated by copepods and euphausiids; the copepod species Calanus pacificus is one of the two dominant copepod species in this region, and the dominant euphausiid species is Euphausia pacifica. The abundances of both of these species vary significantly with El Niño Southern Oscillation conditions.

The PAL study area encompasses a 200 x 500 km region extending from the nearshore coastal zone heavily influenced by seasonal sea ice cover to the open Southern Ocean, and from a northern area where sea ice cover is now limited to only the colder winters, to the south where perennial sea ice cover persists into summer months. In this region, primary production is dominated by unicellular phytoplankton and limited by light availability to the October-April period. The region is characterized by spring phytoplankton blooms that have declined by up to 90% in the northern region since 1978.

Biologically-mediated carbon export transports carbon from the sunlit surface layers into the ocean's interior where it can be sequestered for centuries.  It is a process mediated primarily by plankton ecology, particularly the phytoplankton that fix inorganic carbon and zooplankton that either rerespire it or repackage it into larger particles.  On a cruise in the CCE, we tracked parcels of water for four-day "cycles" during which we measured carbon flux and biological rates while measuring net changes to the plankton community.  These experimental cycles provided

Dispersal ability can affect the dynamics and composition of intertidal communities. Sandy beach ecosystems, where several key taxa have limited dispersal, are increasingly impacted by growing coastal development, and human use, while facing additional habitat loss and fragmentation from sea level rise. Implications of low dispersal rates for populations of key beach taxa, such as talitrid amphipods, include susceptibility to local extinctions and potentially lengthy recolonization times relative to lifespans/generation times.

A conspicuous feature of the Western Antarctic Peninsula (WAP) continental shelf is the presence of deep submarine canyons that extend from the shelf break to the land margin, where during summer large colonies of breeding Adélie penguins occur.

Ocean acidification has severe implications for marine ecosystems. Tropical coral reef communities are particularly vulnerable as they are dominated by marine calcifiers such as corals and crustose coralline algae (CCA). CCA are a fundamental component of reef communities in that they cement reef fragments together, provide critical settlement cues for coral larvae, build reef caps (algal ridges), and are a source of primary production. Despite the key role of CCA in tropical communities, little is known about species- specific physiological responses to ocean acidification.

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 The productivity of giant kelp forests is highly variable across time and space. Winter storms and summer periods of nutrient limitation act as bottom-up regulators of kelp abundance and growth in a geography-dependent manner. Our goal is to develop a predictive understanding of giant kelp forest dynamics in the nearshore waters of California using a combination of (i) bio-optical modeling of kelp productivity, (ii) high-resolution remote sensing of kelp cover, biomass and its physiological state.