bluuebunny/crossref_metadata_2025 huggingface dataset:
4  Phylogeny of the dasycladales (ulvophyceae, chlorophyta) based on analyses of nuclear‐encoded large subunit rDNA
Authors: M. P. Ashworth , F. W. Zechman
Published: January 2004

The Dasycladales is an ancient order of tropical benthic marine green algae, unique in their radially arranged unicellular thalli and well‐preserved fossil record due to extensive calcification of the thallus. The inference of an accurate phylogeny for the Dasycladales is important in order to better understand stratigraphy, character evolution, and classification. Previous analyses (rbcL and 18S rDNA) suggested that the Family Acetabulariaceae is monophyletic, but that the Family Dasycladaceae is a basal paraphyletic assemblage. However, the two data sets disagreed regarding genus‐ and species‐level relationships within the Dasycladales. For example, the placement of the genera, Halicoryne, Bornetella and Cymopolia were incongruent. Given the conflicting results of these previous analyses, the current project examined a third highly conserved nuclear‐encoded gene, 26S rDNA. Aligned 26S rDNA sequences were analyzed with parsimony and model‐based methods and compared to previous results based on18S and rbcL sequences. Family‐level relationships based on 26S rDNA were congruent with previous studies: the Acetabulariaceae is monophyletic while the Dasycladaceae is paraphyletic. In addition, acetabulariacean genera are not monophyletic, suggesting that the presence of a corona inferior or calcification of gametes may not be appropriate to define genera. Within the Dasycladaceae, the basal position of Cymopolia is supported by 26S rDNA, a result congruent with rbcL and stratigraphy but not with 18S data. These results will be discussed in the context of morphological character evolution, fossil stratigraphy and family, tribal and generic relationships among these living algal fossils. Supported in part by NSF grant DEB‐0128977 to FWZ.
40  Phytoplankton biomass and community dynamics in the lake pont‐chartrain estuary of southeast louisiana, usa: effects of light and nutrients upon seasonal and spatial patterns
Authors: Evens T. J. , Wee J. L. , Kirkpatrick G. J. , Millie D. F. , Boihem L. L.
Published: January 2004

A yearlong study (2002–2003) was conducted in the Lake Pontchartrain Estuary (LPE) of Southeast Louisiana in order to examine the temporal and spatial variability of phytoplankton biomass and community dynamics in relation to nutrients, light climate and other abiotic parameters. Variability was assessed through a north‐south transect across the estuary and at five of the major tributaries of the LPE at bi‐weekly intervals. Phytoplankton pigmentation was analyzed by HPLC and used to calculate biomass (as chlorophyll a) and to determine the relative abundances of phylogenetic groups and taxa (via CHEMTAX). Microscopic analyses of select samples were used to verify the efficacy of the CHEMTAX method in the waters of the LPE. Water‐column up‐/down‐welling irradiance (PAR) and colored dissolved organic matter (CDOM) measurements were used to characterize the light climate. Results indicate that LPE phytoplankton biomass and community composition are: 1) highly variable at the spatial and temporal scales of this study, 2) can significantly impact the light field of the LPE, and 3) are influenced by macro‐nutrient ratios.
41  Incidence of paralytic shellfish toxin in bivalve mollusc tissue from the oregon coast
Authors: Everroad R. C. , Cannon D. , Burkland K. R. , Wood A. M.
Published: January 2004

Saxitoxin and domoic acid sequestration by bivalve molluscs occurs periodically along the Oregon coast, presumably as a result of harmful algal blooms (HABs). Since 1958 and more continuously since 1979, the Oregon Shellfish Program (OSP) has assayed toxin levels in these molluscs as part of a monitoring program for paralytic (PSP) and amnesic (ASP) shellfish poisoning. We have created a working data base for all PSP sampling by the OSP between 1958 and 2001 and have examined the data for spatial and temporal trends in the appearance of toxin in shellfish, amount of toxin, and apparent duration of toxic events. In this report, we examine the data from the five stations with the longest record of continuous sampling (1979–2000) for evidence of correlation with El Niño events, upwelling, and/or a pattern of increasing frequency or intensity of toxic events. We also compare the pattern of appearance of toxin at open coast stations with the timing of first appearance of toxin in shellfish at adjacent estuarine stations. This is an important analysis because, in Oregon, shellfish closures due to PSP occur frequently in mussel beds on the open coast and the source of toxin‐producing organisms is unknown.
42  Diversity of phycoerythrin‐containing picocyanobacteria that share the same spectral phenotype
Authors: Everrroad R. C. , Wood A. M.
Published: January 2004

Phycoerythrin (PE) is an important light‐harvesting pigment for many marine picocyanobacteria. There are numerous spectral forms of PE, which differ in their ability to absorb blue and green wavelengths of light, depending on the precise chromophore composition. It remains unclear how the evolutionary history of this family of proteins relates to the diversity of the marine picocyanobacteria. In order to ascertain the level of diversity present in marine picocyanobacterial communities and to determine if specific spectral phenotypes are homologous or convergent, we have begun to examine the genetic diversity found in marine picocyanobacterial strains that share the same or similar spectral signatures for PE fluorescence. The strains we examined are all clonal cultures isolated from a range of environments, including the Arabian Sea and Black Sea. We report results from sequence data obtained using degenerate primers for 16S rRNA, rpoC1, and PE genes; we also examine the utility of taxonomically grouping these organisms by using physiological characteristics such as size and PE signature.
43  Testeria gen. nov. (dinophyceae) from manatee cay belize, Central America
Authors: Faust M. A.
Published: January 2004

A new marine dinoflagellate genus, Testeria gen. nov., is reported from coral reef‐mangrove pond. A new generic name is proposed for two species: Testeria novellus sp. nov. and a new combination fot Testeria steidingerae (Balech) comb. nov. These two species differ in thecal plate morphology from Protoperidinium species based on the following characteristics. Plates of Testeria novellus and T. steidingerae exhibit: 1) a wide, symmetric, ortho apical plate 1' disconnected from a slender apical horn and in direct contact with the cingulum. 2) apical pore complex absent. 3) anterior intercalary plate (2a) hexa situated dorsally. The thecal plate formula is as follows: 4′, 3a, 7′′, 4c)3+t), 5′′′, 6s, 2′′′′. Cells are colorless or pale pink, chloroplasts absent. The similarities and differences of Testeria and Protoperidinium are discussed with respect to their taxonomical history, species associations and ecology.
44  Diversity of the picoplankter choricystis (trebouxiophyceae, chlorophyta) from minnesota and north dakota lakes
Authors: Fawley Karen P. , Fawley M. W.
Published: January 2004

Choricystis (Trebouxiphyceae, Chlorophyta) is considered a very common member of the freshwater picoplankton. We have established a culture collection from Itasca State Park (ISP), Minnesota, and Arrowwood National Wildlife Refuge (ANWR), North Dakota, that includes many Choricystis isolates. We examined 109 Choricystis isolates from ISP and 19 isolates from ANWR using PCR‐RFLP of the rbcL gene. Twelve types for ISP and 7 types forANWR were distinguished by this technique. Sequence analysis revealed additional diversity within some of the RFLP types. Moreover, none of the Choricystis isolates from ANWR possessed rbcL sequences identical to any isolate from ISP. Phylogenetic analysis of the sequence data revealed at least 2 major lineages. These results indicate that Choricystis is much more diverse than previously thought. This material is based upon work supported by the National Science Foundation under Grant Nos. DEB‐0128953, DBI‐0070387 and MCB
45  Phylogeny and systematics of pseudodictyosphaerium, mychonastes and related coccoid green algae (chlorophyceae)
Authors: Fawley M. W. , Fawley K. P. , Buchheim J. A. , Buchheim M. A.
Published: January 2004

Species of Mychonastes, Pseudodictyosphaerium, and Korshpalmella all have spherical (or nearly so) coccoid cells without pyrenoids. Mychonastes and Pseudodictyosphaerium are apparently frequent components of the picoplankton of lakes, although they had not been reported from North America prior to our studies. We have examined several isolates of Mychonastes, Pseudodictyosphaerium, and Korshpalmella from lakes and ponds in Itasca State Park, Minnesota (USA) and Arrowwood National Wildlife Refuge, North Dakota (USA). These isolates comprise 5 different 18S rDNA sequence types, none of which have a sequence identical to any published sequence for Mychonastes or Pseudodictyosphaerium. Four of these 18S types produce solitary cells, consistent with Mychonastes spp. However, other isolates all have identical 18S rDNA sequences, but are either unicellular, colonial with connecting stalks, or colonial in an amorphous matrix, consistent with Mychonastes spp., Pseudodictyosphaerium spp. or Korshpalmella spp, respectively. For some isolates, the colonial character is plastic, with different morphologies seen with different growth conditions. Ribosomal ITS and rbcL sequences also indicate little or no diversity among the isolates with various morphologies. These results suggest that the colonial habit is not a reliable generic character. Phylogenetic analyses of both rbcL and 18S rDNA sequences indicate that Mychonastes and Pseudodictyosphaerium spp. are a distinct lineage within the Chlorophyceae and should be placed in a new family. This material is based upon work supported by the National Science Foundation under Grant Nos. DEB‐0128953, DEB‐0129030, DBI‐0070387 and MCB‐0084188.
46  Near shore sediment diatoms of the great lakes and their use as biological indicators
Authors: Ferguson M. J. , Halady S. W. , Sgro G. V. , Johansen J. R.
Published: January 2004

The great Lakes Environmental Indicators (GLEI) project, funded through the U.S. EPA, has set goals to identify taxa that will be useful in determining ecosystem integrity in near shore waters of the Great Lakes ecosystem. Through the development of biological indices, rapid, consistent, and inexpensive methods of bioassessment of the Great Lakes can be utilized. This particular study focuses on the use of near shore sediment diatoms. Sediment core collection and water sampling and analysis were completed at nearly 100 stratified randomly selected sites across all five of the Great Lakes. Canonical correspondence analysis (CCA) indicated a gradient of water quality throughout the Great Lakes. Lake Superior was determined to have the lowest concentration of measured nutrients, while Lake Erie and Lake Ontario had the highest. Lake Michigan and Lake Huron shared a similar transitional water quality. Although analyses and indices have been developed thus far, GLEI is in its third year of a 4‐year schedule.
47  Phenology of Paralemanea Annulata (lemaneaceae, rhodophyta) in a low‐order woodland stream
Authors: Filkin N. R. , Vis M. L.
Published: January 2004

Paralemanea annulata (Kütz) Vis et Sheath, a member of Lemaneaceae (Batrachospermales, Rhodophyta), is patchy in its distribution across North America, but seems to be most prevalent in the southern United States. Although the stages in the life history of this alga are well‐documented, only scant details are available about the timing of these events and which environmental factors may act as cues. Studies conducted on other members within this family showed correlations between growth and environmental parameters such as daylength, temperature and current velocity. Our study was conducted to investigate whether P. annulata was similarly affected by environmental parameters. A stream reach with varying current velocity and light regimes was investigated. Macroscopic gametophytes were present December‐July and had spermatangia present in all months except December. The presence of carposporophytes in thalli was observed in May and June. The thalli were heavily colonized by Audouinella hermannii March‐June after which the gametophytes were not present. This also corresponded with the drying up of the stream and increased water temperature. New growth of gametophytes was observed in December. Gametophyte percent cover showed a significant positive correlation with both current velocity (p<0.001) and light intensity (p<0.001). Other parameters were correlated for certain regions of the stream reach based on light and current velocity regimes.
48  The effects of environmental factors on the resumption of photosynthetic activity of cyanobacterial mats following rehydration
Authors: Fleming E. D. , Norris T. B. , Castenholz R. W.
Published: January 2004

Extensive cyanobacterial mats cover the intertidal zone near Guerrero Negro, Baja California Sur. These mats are exposed to extreme desiccation and osmotic stress between tidal flows and rains, and spend most of the time dry and metabolically inactive. Therefore, periods of hydration are extremely important for growth as well as for repair of cellular damage from desiccation and ultraviolet radiation (UVR) accrued when the mat is dry. PAM fluorometry in conjunction with carbon incorporation assays were used to determine the effects of salinity, irradiance and UVR on the recovery of photosynthetic activity in these mats after an extended period of desiccation. The mat used in our study was primary composed of Lyngbya sp. Photosynthetic activity recovery rates (using PAM fluorometry) decreased with increasing salinity. This trend was similar under high and low light intensities, but rates were significantly lower under low light. Alternatively, the carbon incorporation method showed rates increased faster in salinities of 27 and 55 ppt than in salinities of 0 or 75 ppt. The Lyngbya mat also failed to recover photosynthetic potential in the dark. Although these mats recovered faster under high intensity light, the effect of salinity on photosynthesis is more complex. UVR did not affect the recovery of photosynthetic activity, no matter which method was used. This lack of effect is most likely due to the high content of the UVR screening pigment, scytonemin, in the upper layer of the mat.
49  Use of biomarkers and core incubations to investigate how changes in benthic ecosystems influence sediment n fluxes in western australia
Authors: Forehead H. I. , Thompson P. A. , Kendrick G. A.
Published: January 2004

The west coast of Australia is dominated by warm, oligotrophic waters, shallow carbonate‐rich sediments and little terrigeneous nutrient input. Irradiance and light penetration are generally high so that benthic primary production is substantial and can equal that in the water column. Microphytobenthos has been shown to have a major influence on nutrient cycling in northern hemisphere waters, but little work has been published on this subject describing the Western Australian marine environment. This presentation focuses upon anthropogenic impacts on microphytobenthos and sediment‐water column nitrogen cycling. The effects of artificial enclosures (harbours) on microphytobenthic communities and nitrogen cycling were examined over an annual cycle at 2 locations in Cockburn Sound, Western Australia. Core and bulk sediment samples were taken from bare sandy areas in water 6–7 m deep at paired sites inside and outside sea walls. Ex‐situ core incubations were used to determine rates of N2 fixation, denitrification, fluxes of macronutrients and oxygen. Bulk sediment samples were analysed for pigments, fatty acids, sterols and grain size. Significant differences were found in both flux and biomarker data between the 2 areas, inside and outside the harbours and between summer and winter. Biomarker data gave information about the algal, bacterial and faunal composition of the sediments and how it changed across the same temporal and spatial scales as the fluxes. The combination of process studies and biomarker information promises to be a powerful tool for resolving a range of questions on the magnitude and mechanisms of nitrogen inputs and exports from these shallow ecosystems.
5  The origin of the dinoflagellate plastid
Authors: Bachvaroff T. R. , Concepcion G. T. , Rogers C. R. , Herman E. M. , Delwiche C. F.
Published: January 2004

Dinoflagellates are griffins, that is the merger of two eukaryotes: a heterotrophic host, the dinoflagellate, and a photosynthetic eukaryote. Our work has been focussed on the endosymbiont's identity and the massive gene transfer implied by secondary endosymbiosis. Dinoflagellates have many different types of chloroplasts, but the majority of photosynthetic dinoflagellates are pigmented with the carotenoid peridinin and chlorophyll c. The chloroplast genome of these organisms is cryptic. Genes that have been attributed to the chloroplast are encoded on minicircles that contain one or two genes. Phylogenetic analysis using these genes suggests that the peridinin chloroplast was derived from haptophytes. Since these minicircle genes have an extreme rate of change phylogenetic methods may produce misleading results. Statistical tests were used to test the quality of phylogenetic methods given these data, particularly the maximum likelihood model. To find plastid associated genes with more reasonable evolutionary rates an expressed sequence tag survey was begun. Among these sequences many typically plastid encoded genes were found including six genes that are exclusively plastid encoded in other eukaryotes. These data suggest massive chloroplast to nucleus gene transfer in dinoflagellates, and fits well with the small complement of minicircle genes. Phylogenetic analyses using these typically plastid encoded genes was also performed. It is now possible to directly test hypotheses of plastid origin within dinoflagellates and the chlorophyll c containing algae.
50  Can the effects of ocean warming on temperate reef communities be accurately predicted? lessons from a large scale, long term field experiment in central California
Authors: Foster M. S.
Published: January 2004

One of the most commonly predicted effects of global ocean warming on marine communities is a poleward shift in the distribution of species with an associated replacement of cold‐water species by warm‐water species. Such predictions are imprecise and based largely on broad correlations in uncontrolled studies that examine changes in species composition and abundance relative to seawater temperature. Before‐After‐Control‐Impact (BACI) analyses of the effects of a large thermal discharge shows that an induced 3.4 deg. C rise in seawater temperature over 10 years along 2 km of rocky coastline resulted in significant community‐wide changes in 150 species of algae and invertebrates relative to controls. Contrary to predictions from biogeographic models, there was no trend towards warm‐water species with southern geographic affinities replacing cold‐species with northern affinities. Instead, communities were greatly altered in apparently cascading responses to changes in abundance of several habitat‐forming taxa, particularly subtidal kelps (e.g. Pterygophora californica) and intertidal foliose red algae (e.g. Mazzaella flaccida). Many temperature sensitive algae decreased greatly in abundance, whereas many invertebrate grazers increased. The results indicate that the responses of temperate reef communities to ocean warming can be strongly coupled to direct effects on habitat‐forming taxa and indirect effects operating through ecological interactions. Given our understanding of temperate reef ecology and its local variability, the results also suggest that accurate predictions of the effects of global ocean warming will be difficult to make.
51  Characterization of the northwestern gulf of Mexico macroalgae
Authors: Fredericq S. , Cho T. O. , Gavio B. , Gurgel C. , Krayesky D. , Lin S.‐M. , Lopez‐bautista J. M. , Phillips N. , Schmidt W. , Won B. Y. , Wysor B.
Published: January 2004

The upper Northwestern Gulf basin is characterized by a relatively shallow but well developed continental shelf with an extensive system of mid‐ and outer shelf hard banks formed on unique tectonically created salt diapirs of varying origin and composition. Collections made by our laboratory from ∼30 m depth by SCUBA while participating in monitoring cruises to the National Marine Sanctuaries of the East and West Flower Garden Banks (Texas), Stetson Banks (Texas) and Sonnier Banks (Louisiana), and while dredging off Louisiana at ∼45–90 m depth, reveal a surprisingly different floristic composition among the sites. Several range extensions, new macroalgal records for the Gulf of Mexico, and the establishment of new species for the region indicate that the NW Gulf encompasses complex macroalgal biota. Our ongoing project includes the development of a modern taxonomic, phylogenetic, morphological and genetic database essential to informed management for preservation of biological diversity. It also provides a framework for seasonal algal composition against which long‐term trends and anomalies in algal distribution and health of the Gulf of Mexico can be assessed at future dates.
52  Beta‐dimethylsulfoniopropionate (Dmsp) as a grazing deterrent in coastal phytoplankton communities
Authors: Fredrickson K. A.
Published: January 2004

While not much is known about the role of chemical defenses in marine planktonic systems, it has been hypothesized that beta‐dimethylsulfoniopropionate (DMSP) may act as a signal for the presence of potentially harmful algal cells. Previous laboratory experiments indicate that DMSP can inhibit feeding in some species of protists, but it is unknown whether this holds true when DMSP is present in coastal communities. Using laboratory and field experiments, the role of dissolved DMSP as a chemical defense in ambient seawater was examined. DMSP (twenty micromolar) added to both laboratory cultures and natural planktonic communities led to a decrease in protist feeding rates; in natural communities, feeding on phytoplankton greater than twenty microns in size was affected more strongly than feeding on smaller cells.
53  A Seaweed's perspective on marine reserves
Authors: Gaines S. , Kinlan B.
Published: January 2004

In response to major changes in coastal ecosystems in recent decades, a number of governmental agencies around the world are establishing marine reserves – areas where removal of animals or plants is prohibited. Although marine reserves are touted as an ecosystem based approach to management of marine resources, the vast majority of attention on reserve design and impact focuses solely on fish. Although a few species of algae are commercially harvested, most are not. As a result, they will receive little direct benefit from protection by reserves aside from habitat protection. From the perspective of a seaweed, the primary impacts of marine reserves will therefore be indirect through species interactions. We examine the rapidly growing theoretical and empirical literature on marine reserves to anticipate the likely responses of seaweeds to exclusion of fishing. The key issues that emerge are: the trophic level of prior fishing and the dispersal scales of seaweeds relative to their competitors and consumers. The latter issue is poorly understood and poses a key challenge to phycologists if we are to effectively incorporate seaweeds into future marine reserve design.
54  Benthic marine algal herbarium of long island sound digital collection
Authors: Cudiner S. , Gillies N. , Yarish C.
Published: January 2004

The University of Connecticut presents the “Benthic Marine Algal Herbarium of Long Island Sound Digital Collection.” The collection is available on the web for teaching and identification purposes. Phase One of this project will be finished later by early next year. Currently, the collection has approximately 60% of all Long Island Sound macroalgae species. The taxonomy is part of a collaboration between the University of Connecticut and the Northeast Algal Society (NEAS). Thus far, the specimens have come from Dr. Charles Yarish's herbarium and from the Environmental Laboratory at Millstone Power Station on Long Island Sound. The botanical illustrations are from “Illustrated Key to the Seaweeds of New England” by Martine Villalard‐Bohnsack. Database features include the ability to create searches and generate sets based on subjects, division, class, order, family, genus, habitat, species, keyword, and location. Data retrieved includes JPG image, cataloged data, map regions, synonyms, and illustrated microscopic, cross section and surface view for some species. The web site is available for use at: http://www.algae.uconn.edu
55  Ice age kelp forests: climate‐driven changes in kelp forest distribution since the last glacial maximum
Authors: Graham M. H.
Published: January 2004

Kelp forest distributions are constrained by the availability of rocky substrate within the depth range tolerable for growth and reproduction, which can vary over relatively short geological timescales (millennia) due to interactions between coastal bathymetry and climate‐driven changes in eustatic sea level. Using GIS, a digital bathymetric map, sea level curves, and published kelp depth tolerances, I reconstructed changes in the size and distribution of giant kelp (Macrocystis pyrifera) forests in the Southern California Bight since the last glacial maximum. Reconstructions predicted that the total area of available kelp forest habitat for the California Channel Islands during the last glacial maximum (18.5 kyr BP; 628 square km) was greater than at present (382 square km) but less than at 16.5 kyr BP (1130 square km). Available kelp forest habitat along the southern California mainland also increased rapidly from 18.5 to 16.5 kyr BP but continued to increase with sea level rise. Differences in the effects of sea level rise on coastal geomorphology between the islands and mainland further constrained the extent of rocky substrate available to kelps. Given biomass and productivity estimates from present‐day kelp forests, these reconstructions suggest more productive and spatially extensive island kelp forests near the last glacial maximum than at present, but the opposite pattern for the mainland. These climate‐driven changes in kelp forest distribution and productivity likely had important historical impacts on the ecology and evolution of the present‐day kelp ecosystem including kelp forest exploitation by early human inhabitants of southern California.
56  Algaebase
Authors: Guiry M. D. , Nic dhonncha E.
Published: January 2004

AlgaeBase (http://www.algaebase.org) is a web‐searchable store of information on those protists generally considered to be algae. Access is free and some 10,000 browser searches on average now take place each month. The database was established in 1996 and at first only included seaweeds. Its main function at this time was as a catalog of the marine algae of Europe for the European Union‐funded BioMar and European Register of Marine Species (ERMS) projects, and for the recently published Atlas and Check‐list of the Seaweeds of Britain and Ireland. The data are now being extended to cover all algae. Over 50,000 names, of which about half are presently accepted species names, are now included, together with the names of some 3500 genera, about 3000 common names, approximately 700 pictures, and in excess of 28,000 literature references. URL‐based links from a number of other databases including the Species 2000 Annual Check‐list, BIOSIS, GenBank, and Codes for Australian Aquatic Biota have been implemented. It is intended to initiate similar connections from new initiatives such as EuroCat and SPICE, and a number of other global biodiversity databases. As part of a further EU‐funded project, SeaweedAfrica (http://www.seaweedafrica.org), AlgaeBase is being completely rewritten as an SQL database with a browser‐enabled interface, enabling access by a panel of taxonomic experts. AlgaeBase hopes thereby to continue to provide high‐quality access to community‐serviced data in the best traditions of the Internet.
57  Systematics of hydropuntia montagne (gracilariaceae, gracilariales, rhodophyta) based on comparative morphology and rbcL sequence analysis
Authors: Gurgel C. F. D. , Fredericq S. , Norris J. N.
Published: January 2004

The taxonomic validity of the genus Hydropuntia Montagne (1843) (including Polycavernosa) within the Gracilariaceae (Gracilariales, Rhodophyta) is controversial. Morphological characters that define species of Hydropuntia are said to be variable and to overlap with those of Gracilaria. Here we present a global phylogenetic study of the family based on a Bayesian analysis of a large rbcL DNA sequence dataset indicating that the genus Hydropuntia forms a well supported monophyletic clade within the family, and recognize Hydropuntia as a genus distinct from Gracilaria. We also conducted smaller phylogenetic analyses in which thirty four Hydropuntia rbcL sequences resulted in two major clades within the genus, comprising a Caribbean clade and an Indo‐Pacific clade. Diagnostic reproductive stages that separate these two clades will be illustrated.
58  Determining the total dietary fiber content in hawaiian marine algae
Authors: Haleakala O. J. , Mccutcheon S. M. , Stuercke B. , Mcdermid K. J.
Published: January 2004

In Hawaii, many species of marine algae are eaten by people, as well as by green sea turtles, reef fish, shore crabs and other herbivorous invertebrates. The Total Dietary Fiber (TDF) content was determined for 30 species (17 Rhodophyta, 4 Phaeophyta, and 9 Chlorophyta) using an enzymatic‐gravimetric procedure. Overall, the seaweeds were rich in fiber. TDF values ranged from 58.48% dry wt. in Ahnfeltiopsis concinna (J. Agardh) Silva et DeCew to 12.80% dry wt. in Codium reediae Silva.
59  Utility of the periphyton index of biotic integrity (PIBI) as an indicator of acid mine drainage impacts in southeastern ohio
Authors: Hamsher S. E. , Vis M. L.
Published: January 2004

In the Appalachian region, numerous streams are polluted with acid mine drainage (AMD). These waters are sulfate‐rich with elevated amounts of total acidity, low pH, and high levels of dissolved metals. Biotic multimetric indices, such as the Periphyton Index of Biotic Integrity (PIBI) have been employed to determine water quality across a variety of environmental conditions and may prove useful for AMD impacts. This study was initiated (1) to evaluate the PIBI for distinguishing AMD impact in streams and (2) to examine whether PIBI scores are impacted by seasonal differences. Twelve AMD and three reference streams were sampled for periphyton in June, August, and October. Water chemistry was collected at least once during the sampling period. Preliminary results showed that PIBI scores were significantly different (p<0.05) among the seasons. In addition, the seasonal trends in PIBI scores among streams were not consistent. The PIBI scores were correlated with six water chemistry variables in August and with at least one variable indicative of AMD in each season sampled. PCA and UPGMA analyses of water chemistry data grouped the streams into five categories: (1) moderately impacted AMD streams with lower total dissolved solids, sulfate, total aluminum, and alkalinity, and higher sulfate; (2) AMD streams with higher alkalinity and lower total aluminum; (3) AMD streams with lower alkalinity and higher total aluminum; (4) reference streams and (5) an outlier reference stream affected by nutrients. Relationships between the groups based on water chemistry and the groups derived from the PIBI will be discussed.
6  Does temperature restrict the latitudinal distribution of symbiotic zooxanthellae within the sea anemone anthopleura elegantissima? Experiments with symbiodinium californium in culture
Authors: Baldauf B. , Muller‐parker G.
Published: January 2004

The intertidal anemone Anthopleura elegantissima hosts two species of symbiotic zooxanthellae with different latitudinal distributions within the anemone host. One of these species, Symbiodinium muscatinei, occurs in anemones from southern California to Washington, while the other species, Symbiodinium californium, is restricted to California and is not found in Oregon or Washington. To investigate if temperature restricts the latitudinal distribution of S. californium, thermal optima and limits to growth and photosynthesis were determined by culturing zooxanthellae at a range of temperatures (5–30 C). Mean growth rates (r) were highest between 15 and 28 C (0.21–0.26 d−1) and extremely low at 5, 10, and 30 C (0.02–0.03 d−1). Light‐saturated maximum photosynthesis (Pmax) increased with temperature between 20 and 30 C (2.93 to 13.18 pg C cell−1·h−1, respectively). The effect of temperature on cell motility and cell volume was assessed by culturing zooxanthellae at 10, 20, and 30 and determining% motility over a 24‐hour period. Cell volumes were also calculated. No apparent change in% motility was observed with respect to time of day. Percent motility and cell volumes were greatest at 10 C (60% and 820 mm3, respectively). S. californium exhibited a dramatic reduction in growth (−89%) and photosynthesis (−64%) at temperatures within the range of average coastal sea temperatures in Oregon and Washington (8–17 C) than at higher temperatures (20–30 C). The results strongly suggest that the latitudinal distribution of S. californium is restricted by its reduced ability to grow or photosynthesize at low temperatures. Comparative studies exploring thermal thresholds of S. muscatinei are needed to conclusively demonstrate the role of temperature in determining the latititudinal distribution of both zooxanthellae in A. elegantissima.
60  Identification of diatom‐lytic bacterium sk‐02 and its capability to degrade stephanodiscus hantzschii
Authors: Han M.‐S. , Kang Y.‐H. , Kim Y. H. , Lee J. B.
Published: January 2004

In order to control harmful algal blooms, many biological approaches have been tried. Specially, there have recently been discussions concerning the roles of bacteria in algal bloom dynamics. Then, algicidal bacteria are expected as an agent considerate for harmful algal blooms control. Development of these organisms as biological control agents involves isolation from environmental samples. With the aim of develop eco‐technology controlling water blooms in fresh waters, we isolated the diatom‐lysing bacteria from the sediments of Lake Seokchon and Pal¡¯tang River‐Reservoir. A soft agar‐overlay technique was used to isolate the diatom lytic bacteria. The SK‐02 showed a diatom lytic activity against Stephanodiscus hantzschii. Taxonomic identification including 16S rDNA base sequencing, and phylogenetic analysis indicated that the isolate SK‐02 had a 99.20% homology in its 16S rDNA base sequence with Pseudomonas putida. The nature of these diatom‐lying components is still under investigation. These results suggest that the indigenous bacteria isolated from the sediments may have a potential in the application and development of eco‐technology controlling harmful water blooms in the fresh water environments.
61  Tank cultivation of ulva (chlorophyceae) in florida
Authors: Hanisak M. D.
Published: January 2004

Ulva spp. has been grown in outdoor tank cultivation at Harbor Branch for the last 25 years. Initially, it was difficult to maintain individual strains throughout the year due to loss of biomass as a result of reproduction under the relatively high water temperature found during the summer. A search for potential warm‐water strains was conducted in nearby marine waters and several promising strains were isolated into laboratory cultures. Growth experiments in the laboratory and in greenhouse cultures resulted in the selection of strains that could grow year‐round, with little or no losses due to reproduction. There is significant physiological variability within a species; the relationship of growth to environmental conditions (e.g., temperature and salinity) is strain dependant. Productivity rates in intensive “tumble” cultivation (high aeration and seawater turnover) are typically 25–30 g dry weight/m2/d, but can reach 35 g dry weight/m2/d, averaged over the annual cycle. Currently, Ulva is being cultivated in this system and used either fresh or as a dried powder, as feed for animals, either to experimental animals in the lab or for inclusion in diets of marine fish. Ulva is a strong candidate in “integrated aquaculture”, which is the focus of renewed interest in recent years, due to Ulva's high rates of growth and nutrient uptake, and its excellent nutritional quality for many marine herbivores.
62  An updated checklist of the seaweeds and seagrasses of oregon
Authors: Hansen G. I.
Published: January 2004

The recent checklist of the marine macrobenthic marine algae and seagrasses of Oregon (Hansen 1997) was based primarily on the literature. Although it revealed a depauperate flora of only 387 species, the low count was thought to be due in part to a lack of adequate floristic investigation in this area. To help correct this problem, a database of the existing collections of marine algae from Oregon was initiated. To date, 7500 specimens from 10 major herbaria have been cataloged. New records from these archived specimens and from some new collections have increased the species count by over 50. Further cataloging and collecting should reveal additional new records for the state, but it is unlikely that the predominantly exposed, sand‐scoured coastline will ever be found to be as species rich as the more habitat diverse neighboring states of Washington and California. In addition to the updated checklist, the poster will include the early collection history of the state and some discussion of the problematic taxa.
63  Environmental change, interspecific interactions, and shifting algal distributions on rocky shores
Authors: Harley C. D. G.
Published: January 2004

Because intertidal organisms live close to their environmental tolerances, intertidal species are considered early harbingers of the effects of global change. Using a combination of spatial environmental gradients and long‐term datasets, I examine the likely consequences of global warming on the distribution of Mazzaella parksii (formerly Mazzaella cornucopiae), a turf‐forming red alga. On Tatoosh Island, WA, M. parksii is restricted almost entirely to north‐facing surfaces. On south‐facing slopes, the upper limit of M. parksii, which is set by abiotic stress, occurs much lower on the shore. However, its lower limit, which is set by herbivores, does not vary with aspect. Because its upper and lower limits are independent across the aspect gradient, M. parksii is effectively “squeezed out” of the system as one moves from a north‐facing to a south‐facing slope. This general pattern is observed at several spatial scales across gradients of wave exposure and air temperature. The vertical distributional patterns of M. parksii also shift across temporal gradients. Over the past 25 years, the upper limit of M. parksii on Tatoosh Island has shifted downshore by approximately 25 cm. Most of this change was driven by three consecutive harsh summers in the mid 1990's. These temporal patterns, combined with the insight gained from spatial patterns, suggest that M. parksii may go locally extinct in many parts of its range as its upper and lower limits converge. Furthermore, because vertical distributional shifts are linked to stochastic climatic effects, temporal change in marine algal populations may be rapid and unexpected.
64  Nucleus‐encoded, plastid‐targeted glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH) indicates a single origin for chromalveolate plastids
Authors: Harper J. T. , Keeling P. J.
Published: January 2004

Plastids (the photosynthetic organelles of plants and algae) ultimately originated through an endosymbiosis between a cyanobacterium and a eukaryote. Subsequently, plastids spread to other eukaryotes by secondary endosymbioses that took place between a eukaryotic alga and a second eukaryote. Recently, evidence has mounted in favour of a single origin for plastids of apicomplexans, cryptophytes, dinoflagellates, haptophytes, and heterokonts (together with their non‐photosynthetic relatives, collectively termed chromalveolates). As of yet, however, no single molecular marker has been described which supports a common origin for all of these plastids. One piece of the evidence for a single origin of chromalveolate plastids came from plastid‐targeted glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH), which originated by a gene duplication of the cytosolic form. However, no plastid GAPDH has been characterized from haptophytes, leaving an important piece of the puzzle missing. We have sequenced genes encoding cytosolic, mitochondrial‐targeted, and plastid‐targeted GAPDH proteins from a number of haptophytes and heterokonts, and found the haptophyte homologues to branch within the strongly supported clade of chromalveolate plastid‐targeted GAPDH genes. Interestingly, plastid‐targeted GAPDH genes from the haptophytes were more closely related to apicomplexan genes than was expected. Overall, the evolution of plastid‐targeted GAPDH reinforces other data for a red algal ancestry of apicomplexan plastids, and raises a number of questions about the importance of plastid loss and the possibility of cryptic plastids in non‐photosynthetic lineages such as ciliates.
65  Nutrient responses of harmful algal blooms in south carolina brackish lagoonal systems
Authors: Hayes K. C. , Lewitus A. J.
Published: January 2004

The widespread occurrence of harmful algal blooms (HABs) in South Carolina brackish lagoons has recently been documented. Over the last 2 years, dense blooms of raphidophytes, dinoflagellates, cyanobacteria, and prymnesiophytes were commonly observed, mostly in storm water retention ponds associated with housing developments or golf courses. As part of an effort to understand the physiological ecology of these blooms, bioassays were performed testing the effects of nutrients on HAB population growth. The first bioassay was conducted on a mixed bloom of Heterosigma akashiwo and Chattonella verruculosa, and the second on a mixed bloom of Fibrocapsa japonica, Karlodinium micrum and C. verruculosa. The growth of all species but F. japonica could be stimulated by the addition of DIN or DON substrates, including nitrate, ammonium, urea, and glycine. F. japonica was only stimulated by the addition of a fertilizer (Miracle Grow™) or an inhibitor of photosynthesis (DCMU). Stimulation by the fertilizer, but not N or P substrates, suggests that this response was related to trace metal (e.g. Fe) use. Growth stimulation by DCMU may reflect a high heterotrophic capability or insensitivity of F. japonica's photosynthetic system to this inhibitor. The results suggest that the nutritional versatility of these species may contribute to their widespread occurrence and ability to form blooms in these low flow, nutrient‐ and organic‐rich systems. Also, the responses of F. japonica infer that contaminant loading (e.g. herbicides with similar effects as DCMU) should be considered as a selective factor in HAB initiation or maintenance.
66  Algal bioremediation of mine waste tailings by application of moss protonema
Authors: Henderson M. , Mitman G. G.
Published: January 2004

Moss was discovered growing on mine waste tailings with high heavy metal content and low pH at the Badger State Mine near Butte, MT. It has been proposed that inoculation of plots with moss protonema, a stage of moss development, will produce a microbial mat. This process is fairly straightforward in mesic environments, but the aridity, acidity and high metal content of the tailings present some difficulty with the establishment of moss protonema or even algae. Consequently, a hydrophilic polymer and nutrients will be applied in addition to the protonema. This combination may assist in the retention of moisture to ensure the growth of the mature moss and other pioneer organisms. Soil from the mine tailings will be analyzed for evidence of cyanobacterial and other algal diversity. Benefits of cyanobacteria growth include their ability to fix nitrogen for use by other plants and production of photosynthates that leak organic carbon into the soil at a rate that can feed the heterotrophic microbes found in the microbial mat. The combination of algae, fungi, bacteria, protists and moss in a self‐sustaining microbial mat may help to stabilize the soil and create a hospitable environment for the colonization of vascular plants. Formation of a microbial mat in this xeric environment of mine waste tailings with the use of a hydrophilic polymer may be an ideal solution for the stabilization of mine wastes.
67  Patterns of reproduction and morphological variation in southern california populations of the lower intertidal kelp egregia menziesii (turner) areschoug
Authors: Henkel S. K. , Murray S. N.
Published: January 2004

Egregia menziesii is a complex kelp with an adult morphology that varies considerably across its geographic range. Fertility in Egregia also varies geographically. We studied intertidal populations of Egregia at three southern California sites to determine spatial and temporal patterns of reproduction, recruit‐qment, and morphology. Growing axes of Egregia were collected monthly to quantify sporophyll production and lateral blade morphology. Band transects were surveyed quarterly (2001) and monthly (2002) to determine temporal patterns of sporophyte recruitment. Sporophylls were found throughout the year, but sporophyll densities showed a strong peak during winter periods of colder seawater temperatures and shorter daylengths. Sporophytes recruited almost exclusively from March to July, suggesting a gametophyte period of <5 months. Lateral blade morphologies varied in a consistent pattern; thalli initially developed spatulate blades but then produced increasing numbers of filiform laterals as axes grew. Thalli in habitats populated by higher grazer densities had shorter axes, dominated by spatulate blades, while those growing under low grazing pressure exhibited longer fronds and more filiform laterals. Differences in lateral morphology had effects on thallus productivity and susceptibility to grazers. Filiform laterals had higher light‐saturated photosynthetic rates than spatulate laterals and a 1‐m long frond with filiform laterals was estimated to be 12% more productive than one with spatulate laterals. Kelp snails, but not urchins, consistently chose spatulate over filiform laterals, this suggests that Egregia thalli dominated by spatulate laterals are more susceptible to grazing molluscs, while lateral morphology has no effect on Egregia's susceptibility to urchins.