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As part of an ongoing investigation into the species delineation and distribution of Porphyra from Long Island Sound to the Canadian Maritimes, cytological investigations are being undertaken. A variety of methods have been attempted and of the techniques used, DAPI fluorescent-dye staining was found to be most preferable. Three different Porphyra purpurea (Roth) C. Agardh populations were found within this geographic range, each with different chromosome numbers or arrangements. Different populations of P. leucosticta Thuret in Le Jolis were also delineated using this cytological method. The use of chromosome counts as an aid to traditional taxonomic methods has proved useful in this species-distribution investigation of Porphyra in the Northwest Atlantic.

The red algae Gracilaria edulis, Hypnea valentiae, Acanthophora spicifera and Sarconema indica have been observed to occur and grow in a culture pond. Over a period of eight months, the algae grew to 104 kg in the pond of 800 sq m. The hydrological conditions in the pond are compared to those in the sea containing natural beds of these algae during the period of observations. This occurenceand growth may open up the possibility of growing  thses algae in culture ponds providing the requisite hydrological and nutrient conditions.

Ocean acidification (OA) is expected to reduce the calcification rates of marine organisms, yet we have little understanding of how OA will manifest within dynamic, real-world systems. Natural CO2, alkalinity, and salinity gradients can significantly  alter local carbonate chemistry, and thereby create a range of susceptibility for different ecosystems to OA. As such, there is  a need to characterize this natural variability of seawater carbonate chemistry, especially within coastal ecosystems. Since  2009, carbonate chemistry data have been collected on the Florida Reef Tract (FRT). During periods of heightened  productivity, there is a net uptake of total CO2 (TCO2) which increases aragonite saturation state (Varag) values on inshore  patch reefs of the upper FRT. These waters can exhibit greater Varag than what has been modeled for the tropical surface  ocean during preindustrial times, with mean (6 std. error) Varag-values in spring = 4.69 (60.101). Conversely, Varag-values on offshore reefs generally represent oceanic carbonate chemistries consistent with present day tropical surface ocean  conditions. This gradient is opposite from what has been reported for other reef environments. We hypothesize this pattern  is caused by the photosynthetic uptake of TCO2 mainly by seagrasses and, to a lesser extent, macroalgae in the inshore  waters of the FRT. These inshore reef habitats are therefore potential acidification refugia that are defined not only in a  spatial sense, but also in time; coinciding with seasonal productivity dynamics. Coral reefs located within or immediately  downstream of seagrass beds may find refuge from OA.

Ocean warming and increased stratification of the upper ocean caused by global climate change will likely lead to declines in the dissolved O2 in the ocean interior (ocean deoxygenation) with implications for ocean productivity, nutrient cycling, carbon cycling, and marine habitat.

Ocean models predict declines of 1 to 7% in the global ocean O2 inventory over the next century, with declines continuing for a thousand years or more into the future. An important consequence may be an expansion in the area and volume of so-called oxygen minimum zones, where O2 levels are too low to support many macrofauna and profound changes in biogeochemical cycling occur. Significant deoxygenation has occurred over the past 50 years in the North Pacific and tropical oceans suggesting larger changes are looming. The potential for larger O2 declines in the future suggests the need for an improved observing system for tracking ocean O2 changes.