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A diminutive new species of Predaea (Gigartinales, Rhodophyta) is described from coral reef habitats in Puerto Rico, Caribbean Sea. It is composed of compressed lobes which radiate to form an irregularly rounded shape. The new species is characterized by its cylindrical cortical cells, 3-celled carpogonial branches, small number of nutritive cells associated with auxiliary cells and initiation of gonimoblasts from connecting filaments. [ABSTRACT FROM AUTHOR]

Dasya puertoricensis is newly described from subtidal habitats in southwestern Puerto Rico. The new species is characterized by its conspicuously dense, brush-like branch tips, rhizoidal cortication and by its indeterminate adventitious filaments which arise from pseudolateral basal cells. Adventitious monosiphonous laterals are absent. Tetrasporangial stichidia normally possess 6 sporangia per fertile whorl. The cystocarps are sessile with cortical cells at their broadened bases enveloping the bearing branches. [ABSTRACT FROM AUTHOR]

Forty eight HPLC peaks from three distinct TLC zones obtained from crude lipid extracts of the tropical marine red alga Spyridia filamentosa were assayed against five pathogenic microorganisms. Of these, nineteen showed detectable activities (seven HPLC peaks from TLC zone 5; five peaks from TLC zone 9; seven peaks from TLC zone 12). Activities by single HPLC peaks were generally against one or two assay microorganisms. The total number of biologically active compounds in a given alga is shown to be substantially greater than can be ascertained by assaying whole-algal extracts. [ABSTRACT FROM AUTHOR]

Forty eight HPLC peaks from three distinct TLC zones obtained from crude lipid extracts of the tropical marine red alga Spyridia filamentosa were assayed against five pathogenic microorganisms. Of these, nineteen showed detectable activities (seven HPLC peaks from TLC zone 5; five peaks from TLC zone 9; seven peaks from TLC zone 12). Activities by single HPLC peaks were generally against one or two assay microorganisms. The total number of biologically active compounds in a given alga is shown to be substantially greater than can be ascertained by assaying whole-algal extracts. [ABSTRACT FROM AUTHOR]

Examines the fatty acid composition of the tropical genus Halimeda. List of Caribbean species; Measurement of principal fatty acids among species; Identification of tetracosanoic acid, pentacosanoic acid, and hexacosanoic acid.

Reduction of visual clarity in streams by diffuse sources of fine sediment is a cause of water quality impairment in New Zealand and internationally, in this paper we introduce the concept of a load of optical cross section (LOCS), which can be used for load-based management of light-attenuating substances and for water quality models that are based on mass accounting. In this approach, the beam attenuation coefficient (units of m-1) is estimated from the inverse of the visual clarity (units of m) measured with a black disc. This beam attenuation coefficient can also be considered as an optical cross section (OCS) per volume of water, analogous to a concentration. The instantaneous 'flux' of cross section is obtained from the attenuation coefficient multiplied by the water discharge, and this can be accumulated over time to give an accumulated `load' of cross section (LOCS). Moreover, OCS is a conservative quantity, in the sense that the OCS of two combined water volumes is the sum of the OCS of the individual water volumes (barring effects such as coagulation, settling, or sorption). The LOCS can be calculated for a water quality station using rating curve methods applied to measured time series of visual clarity and flow. This approach was applied to the sites in New Zealand's National Rivers Water Quality Network (NRWQN). Although the attenuation coefficient follows roughly a power relation with flow at some sites, more flexible bess rating curves are required at other sites. The hybrid mechanistic-statistical catchment model SPARROW (SPAtially Referenced Regressions On Watershed attributes), which is based on a mass balance for mean annual load, was then applied to the NRWQN dataset. Preliminary results from this model are presented, highlighting the importance of factors related to erosion, such as rainfall, slope, hardness of catchment rock types, and the influence of pastoral development on the load of optical cross section. [ABSTRACT FROM AUTHOR]