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Cladorhiza Corona Sp. Nov. (Porifera : Demospongiae : Cladorhizidae) From The Aleutian Islands (Alaska), H. Lehnert, Les Watling, R. Stone
Cladorhiza Corona Sp. Nov. (Porifera : Demospongiae : Cladorhizidae) From The Aleutian Islands (Alaska), H. Lehnert, Les Watling, R. Stone
Marine Sciences Faculty Scholarship
A new species of Cladorhizidac, front the Aleutian Islands is described and compared with all known species of Cladorhizza worldwide. Cladorhiza corona sp. now has a unique growth form with two planes of differently shaped appendages. Appendages are Inserted directly at the stalk; a spherical or conical body at the stalk is lacking. It is the only species reported where different spicule types occur in three morphologically different areas of the sponge. The spiculation of the basal plate is characterized by the occurrence of short, thick anisoxcas and the lack of anisochelae. Anisochelac arc found in the stalk and the …
Reproductive Biology Of The Deep-Sea Polychaete Gorgoniapolynoe Caeciliae (Polynoidae), A Commensal Species Associated With Octocorals, Kevin Eckelbarger, Les Watling, H. Fournier
Reproductive Biology Of The Deep-Sea Polychaete Gorgoniapolynoe Caeciliae (Polynoidae), A Commensal Species Associated With Octocorals, Kevin Eckelbarger, Les Watling, H. Fournier
Marine Sciences Faculty Scholarship
Some aspects of the reproductive biology of the polychaete Gorgoniapolynoe caeciliae have been described for the first time. Gorgoniapolynoe caeciliae is a deep-sea commensal species associated with Candidella imbricala, all octocoral that populates the New England Seamount chain. Gorgoniapolynoe caeciliae is a dioccious species with an equal sex ratio and fertile segments throughout most of the adult body. The gonads of both sexes are associated with genital blood vessels emerging from the posterior surface of most intersegmental septa. In the female, oogenesis is intraovarian with oocytes being retained within the ovary until vitellogenesis is completed. The largest female examined contained …
A Comparison Of Hydrographically And Optically Derived Mixed Layer Depths, D. G. Zawada, J. R.V. Zaneveld, Emmanuel Boss, W. D. Gardner, M. J. Richardson, A. V. Mishonov
A Comparison Of Hydrographically And Optically Derived Mixed Layer Depths, D. G. Zawada, J. R.V. Zaneveld, Emmanuel Boss, W. D. Gardner, M. J. Richardson, A. V. Mishonov
Marine Sciences Faculty Scholarship
Efforts to understand and model the dynamics of the upper ocean would be significantly advanced given the ability to rapidly determine mixed layer depths (MLDs) over large regions. Remote sensing technologies are an ideal choice for achieving this goal. This study addresses the feasibility of estimating MLDs from optical properties. These properties are strongly influenced by suspended particle concentrations, which generally reach a maximum at pycnoclines. The premise therefore is to use a gradient in beam attenuation at 660 nm (c660) as a proxy for the depth of a particle-scattering layer. Using a global data set collected during World Ocean …
Theoretical Derivation Of The Depth Average Of Remotely Sensed Optical Parameters, J. Ronald V. Zaneveld, Andrew H. Barnard, Emmanuel Boss
Theoretical Derivation Of The Depth Average Of Remotely Sensed Optical Parameters, J. Ronald V. Zaneveld, Andrew H. Barnard, Emmanuel Boss
Marine Sciences Faculty Scholarship
The dependence of the reflectance at the surface on the vertical structure of optical parameters is derived from first principles. It is shown that the depth dependence is a function of the derivative of the round trip attenuation of the downwelling and backscattered light. Previously the depth dependence was usually modeled as being dependent on the round trip attenuation. Using the new relationship one can calculate the contribution of the mixed layer to the overall reflectance at the surface. This allows one to determine whether or not to ignore the vertical structure at greater depth. It is shown that the …
Uncertainties Of Inherent Optical Properties Obtained From Semianalytical Inversions Of Ocean Color, Peng Wang, Emmanuel S. Boss, Collin Roesler
Uncertainties Of Inherent Optical Properties Obtained From Semianalytical Inversions Of Ocean Color, Peng Wang, Emmanuel S. Boss, Collin Roesler
Marine Sciences Faculty Scholarship
We present a method to quantify the uncertainties in the in-water constituent absorption and backscattering coefficients obtained from an inversion of remotely sensed reflectance (rrs). We first find a set of positive inversion solutions within a given uncertainty range around the values of the inverted rrs. The uncertainties of the solutions are then computed based on the statistics of these solutions. We demonstrate the uncertainty calculation algorithm using a specific semianalytic inversion model applied to both a field and a simulated data set. When the associated uncertainties are taken into account, the inverted parameters are generally within the uncertainties of …
Physical And Biological Controls On The Latitudinal Asymmetry Of Surface Nutrients And Pco(2) In The Central And Eastern Equatorial Pacific, M. S. Jiang, Fei Chai
Physical And Biological Controls On The Latitudinal Asymmetry Of Surface Nutrients And Pco(2) In The Central And Eastern Equatorial Pacific, M. S. Jiang, Fei Chai
Marine Sciences Faculty Scholarship
Surface nutrients and dissolved inorganic carbon (DIC) in the central (CEP) and eastern equatorial Pacific (EEP) show much higher concentrations to the south than to the north of the equator. In this study, the physical and biological controls on this asymmetry are investigated using a coupled physical-biogeochemical model. Two numerical experiments are conducted to examine the effects of asymmetrical photosynthetic efficiency (a) due to asymmetrical iron supply about the equator. The experiment with asymmetrical photosynthesis produces improved results as compared with historical observations. A nitrate budget analysis suggests that in the EEP the divergence of upwelling waters controls the surface …
Denitrification In The Hypolimnion Of Permanently Ice-Covered Lake Bonney, Antarctica, B. B. Ward, J. Granger, M. T. Maldonado, K. L. Casciotti, S. Harris, Mark Wells
Denitrification In The Hypolimnion Of Permanently Ice-Covered Lake Bonney, Antarctica, B. B. Ward, J. Granger, M. T. Maldonado, K. L. Casciotti, S. Harris, Mark Wells
Marine Sciences Faculty Scholarship
The distribution of denitrification was investigated in the hypolimnion of the east and west lobes of permanently ice-covered Lake Bonney, Taylor Valley, Antarctica. Anomalously high concentrations of dissolved inorganic nitrogen (DIN; nitrate, nitrite, ammonium and nitrous oxide) in the oxygen-depleted hypolimnion of the east lobe of the Lake implied that denitrification is or was active in the west, but not in the east lobe. While previous investigations reported no detectable denitrification in the east lobe, we measured active denitrification in samples from both the east and west lobes. In the west lobe, measured denitrification rates exhibited a maximum at the …
Carbon-Based Ocean Productivity And Phytoplankton Physiology From Space, M. J. Behrenfeld, Emmanuel Boss, D. A. Siegel, D. M. Shea
Carbon-Based Ocean Productivity And Phytoplankton Physiology From Space, M. J. Behrenfeld, Emmanuel Boss, D. A. Siegel, D. M. Shea
Marine Sciences Faculty Scholarship
Ocean biogeochemical and ecosystem processes are linked by net primary production (NPP) in the ocean's surface layer, where inorganic carbon is fixed by photosynthetic processes. Determinations of NPP are necessarily a function of phytoplankton biomass and its physiological status, but the estimation of these two terms from space has remained an elusive target. Here we present new satellite ocean color observations of phytoplankton carbon (C) and chlorophyll (Chl) biomass and show that derived Chl:C ratios closely follow anticipated physiological dependencies on light, nutrients, and temperature. With this new information, global estimates of phytoplankton growth rates (mu) and carbon-based NPP are …