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The Toxicology Investigators Consortium 2023 Annual ReportNARA Subscribed
The Toxicology Investigators Consortium 2022 Annual ReportNARA Subscribed
The distribution of mycosporine-like amino acids in phytoplankton across a Southern Ocean transectOA Marine
Interactions between phytoplankton and ultraviolet radiation (UVR: 280 – 400 nm) are undergoing changes dictated by variability in ocean temperature, the depth of mixed layers, nutrient availability, and the thickness of the ozone layer. There are a variety of mechanisms for phytoplankton to cope with UVR stress, one of the most prevalent being the presence of mycosporine-like amino acids (MAAs). Despite the importance of thes...
Natal experience and pre‐breeding environmental conditions affect lay date plasticity in Savannah SparrowsNARA Subscribed
Phenotypic plasticity allows organisms to adjust the timing of life‐history events in response to environmental and demographic conditions. Shifts by individuals in the timing of breeding with respect to variation in age and temperature are well documented in nature, and these changes are known to scale to affect population dynamics. However, relatively little is known about how organisms alter phenology in response to other d...
Development of a multi-excitation fluorescence (MEF) imaging method to improve the information content of benthic coral reef surveysNARA Subscribed
Benthic surveys are a key component of monitoring and conservation efforts for coral reefs worldwide. While traditional image-based surveys rely on manual annotation of photographs to characterise benthic composition, automatic image annotation based on computer vision is becoming increasingly common. However, accurate classification of some benthic groups from reflectance images presents a challenge to local ecologists and co...
Light and nutrient control of photosynthesis in natural phytoplankton populations from the Chukchi and Beaufort seas, Arctic OceanNARA Subscribed
During the 2010–2011 ‘Impacts of Climate Change on the EcoSystems and Chemistry of the Arctic Pacific Environment’ project, we measured photosynthetic parameters in natural Arctic phytoplankton assemblages from the Chukchi and Beaufort seas. Water‐column samples were taken from the near surface (3.1 ± 0.9 m) and subsurface (28 ± 10.3 m) at ∼ 85 stations each year representing a wide range of ecological conditions, including un...
Processes influencing phytoplankton bloom development in the southern Drake Passage were studied using shipboard iron‐enrichment incubations conducted across a surface chlorophyll gradient near the Antarctic Peninsula, in a region of water mass mixing. Iron incubation assays showed that Antarctic Circumpolar Current (ACC) waters were severely iron limited, while shelf waters with high ambient iron concentrations (1–2 nmol L −1...
Estimation of the absorption and backscattering coefficients from inߚwater radiometric measurementsNARA Subscribed
Numerical simulations of radiative transfer within the ocean surface mixed layer have been used to derive a set of simple equations for estimating the absorption, a, and backscattering, b b , coefficients in the blue‐green spectral region from measurements of downwelling irradiance, E d , upwelling irradiance, E u , and upwelling nadir radiance, L u . Two relationships are used in this derivation: (i) irradiance reflectance, R...
Photophysiological acclimation of Phaeocystis antarctica Karsten under light limitationNARA Subscribed
Primary production models and pigment algorithms for remote optical systems including satellites, moorings, or drifters depend on an improved understanding of the relationship between spectral light absorption, pigments, and photosynthesis for species of phytoplankton that are widespread and numerically abundant. Cultures of colonial Phaeocystis antarctica , a prymnesiophyte that can dominate the phytoplankton community in the...
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