Digital library

  • Coral reef fish abundance and diversity of seagrass beds in Kavaratti atoll, Lakshadweep, India

    The community organization of coral reef fishes in the seagrass sub-habitat of Kavaratti toll, Lakshadweep, India was studied during the period from January 1991 to June 1992. Twenty-seven families represented by 65 species were recorded by the visual censes method. The community diversity for families and species was 2.49 and 3.14 respectively. Juveniles and sub-adults of the most adult reef fish, which inhabit other sub-habitats, were recorded here. The high species diversity in the seagrass beds is due to their roles as nurseries, shelter and foraging grounds for many species.

    Labridae, Chaetodontidae, Acanthuridae and Mullidae were the most speciose families. Ocurrence of siganids was highly seasonal. The cover that seagrass canopy provides conceals many species and perhaps influenced counts. The occurrence of balistids could be related to the presence of interstitial and patches and abundant invertebrate food. Scorpaenids subsisted on abundant invertebrates and juveniles fishes. High counts and pronounced variations make seagrass beds unstable habitats. However, monsoon assemblages were relatively stable perhaps due to lack of excessive new recruits and a habitat shift by most species.

    Author(s): Vijay Anand, P E, Pillai, N G K

  • Coral and macroalgal exudates vary in neutral sugar composition and differentially enrich reef bacterioplankton lineages

    Increasing algal cover on tropical reefs worldwide may be maintained through feedbacks whereby algae outcompete coral by altering microbial activity. We hypothesized that algae and coral release compositionally distinct exudates that differentially alter bacterioplankton growth and community structure. We collected exudates from the dominant hermatypic coral holobiont Porites spp. and three dominant macroalgae (one each Ochrophyta, Rhodophyta and Chlorophyta) from reefs of Mo’orea, French Polynesia. We characterized exudates by measuring dissolved organic carbon (DOC) and fractional dissolved combined neutral sugars (DCNSs) and subsequently tracked bacterioplankton responses to each exudate over 48h, assessing cellular growth, DOC/DCNS utilization and changes in taxonomic composition (via 16S rRNA amplicon pyrosequencing). Fleshy macroalgal exudates were enriched in the DCNS components fucose (Ochrophyta) and galactose (Rhodophyta); coral and calcareous algal exudates were enriched in total DCNS but in the same component proportions as ambient seawater. Rates of bacterioplankton growth and DOC utilization were significantly higher in algal exudate treatments than in coral exudate and control incubations with each community selectively removing different DCNS components. Coral exudates engendered the smallest shift in overall bacterioplankton community structure, maintained high diversity and enriched taxa from Alphaproteobacteria lineages containing cultured representatives with relatively few virulence factors (VFs) (Hyphomonadaceae and Erythrobacteraceae). In contrast, macroalgal exudates selected for less diverse communities heavily enriched in copiotrophic Gammaproteo- bacteria lineages containing cultured pathogens with increased VFs (Vibrionaceae and Pseudoal- teromonadaceae). Our results demonstrate that algal exudates are enriched in DCNS components, foster rapid growth of bacterioplankton and select for bacterial populations with more potential VFs than coral exudates. 

    Author(s): Craig E Nelson, Stuart J Goldberg, Linda Wegley Kelly, Andreas F Haas, Jennifer E Smith, Forest Rohwer, Craig A Carlson

  • Conversion of Seaweed to Biofuels - Potential and Challenges

    A PDF on SINTEF's "Conversion of Seaweed to Biofuels - Potential and Challenges" Power Point.

    Author(s): Olaf T. Berglihn, Inga M. Aasen, Bernd Wittgens

  • Consumption of seaweeds and the human brain

    Much of the content of the human head is brain matter. This functions as the epicenter of human physical ex- istence, including a sense of well-being and the manifestation of human consciousness. The human brain is a precious and complex organ which increases from 350 to 400 g in infants to 1.3–1.4 kg in adults; it comprises ca. 78 % water, 12 % lipid, 8 % protein, and 1 % carbohydrate. Significant progress in behavioral and analytical science has accelerated understand- ing of the multifaceted responses of the brain to stimuli, whether it be the microbial breakdown products of ingested foods, the influences of environment, or in relation to genetic predisposition. The science of seaweeds, and particularly their broad range of applications, is gathering momentum as studies repeatedly underscore the natural health and nutritional bene- fits of dietary macroalgae. This article reviews research highlighting the potential impacts of the consumption of a variety of seaweeds on human brain health and includes the- ories in relation to the benefits to early Homo sapiens. The emphasis is on a varied diet including macroalgae and the gut/ 

    microbe/brain axis, the importance of polyunsaturated fatty acids, and the impacts of anti-oxidant activities in neuropro- tection. These elements have the capacity to help in the de- fense of human cognitive disorders, such as dementia, Alzheimer’s disease, depression, bipolar diseases, and adverse conditions characterized by progressive neurodegeneration. Psychological benefits associated with the moderate con- sumption of a diet fortified with macroalgae are also discussed in terms of reduction of depressive symptoms and furthermore highlighting possible improvements in sexual function. 

    Author(s): M. Lynn Cornish, Alan T. Critchley, Ole G. Mouritsen

  • Construction of Artificial Seaweed Beds; Using the Spore Bag Method

    Kelp forests and Sargassum beds not only are commercially important in themselves but also play an important role in spawning, breeding and feeding grounds for many kind of fish, shellfish, lobster and other important fisheries resources (Komatsu et al. 1982; Komatsu 1985; Ohno et al. 1990; Watanuki and Yamamoto 1990; Terawaki et al. 1998). The distributions of kelp forests comprising of the Ecklonia and Eisenia species are restricted to warm-water regions. A number of ecological studies on these plants have been undertaken with particular attention focused the re-establishment of kelp forests. This is due to declining populations that are a result of various factors, including human activities (Tsutsui et al. 1996). Thus, there has been development of construction techniques of artificial foundation, for kelp forests, and transplanting techniques of seed and adult marine algae, on artificial foundations (Hasegawa et al. 1995). Techniques of formation for seaweed bed may fall under either of the following classifications: 1. Spore dispersal technique; 2. The spore bag technique; 3. Ropeseeding technique; 4. Adult-plant transplantation method; 5. Concrete blocks; 6. The threading technique; 7. Gravel-bag technique; and 8. Transplantation of young plants (Largo and Ohno 1993). In this study, we used the spore bag on the roof of an artificial iron reef and a natural rock for a seaweed bed. The present paper describes the formation of seaweed beds by the spore bag method on an artificial iron reef and a natural rock (habitat).

    Author(s):

  • Construction of Artifical Seaweed Beds; Using the Spore Bag Method

    Kelp forests and Sargassum beds not only are commercially important in themselves but also play an important role in spawning, breeding and feeding grounds for many kind of fish, shellfish, lobster and other important fisheries resources (Komatsu et al. 1982; Komatsu 1985; Ohno et al. 1990; Watanuki and Yamamoto 1990; Terawaki et al. 1998). The distributions of kelp forests comprising of the Ecklonia and Eisenia species are restricted to warm-water regions. A number of ecological studies on these plants have been undertaken with particular attention focused the re-establishment of kelp forests. This is due to declining populations that are a result of various factors, including human activities (Tsutsui et al. 1996). Thus, there has been development of construction techniques of artificial foundation, for kelp forests, and transplanting techniques of seed and adult marine algae, on artificial foundations (Hasegawa et al. 1995).Techniques of formation for seaweed bed may fall under either of the following classifications: 1. Spore dispersal technique; 2. The spore bag technique; 3. Ropeseeding technique; 4. Adult-plant transplantation method; 5. Concrete blocks; 6. The threading technique; 7. Gravel-bag technique; and 8. Transplantation of young plants (Largo and Ohno 1993).In this study, we used the spore bag on the roof of an artificial iron reef and a natural rock for a seaweed bed. The present paper describes the formation of seaweed beds by the spore bag method on an artificial iron reef and a natural rock (habitat).

    Author(s): Chang Geun Choi, Yukihiko Serisawa, Masao Ohno, Chul Hyun Sohn

  • Connecticut-Sized Dead Zone Found in Gulf of Mexico

    Imagine if all of the animals throughout the entire state of Connecticut left or died. This is what happens every year in the Gulf of Mexico. The size of the dead zone varies—sometimes it’s as big as New Jersey or only the size of Rhode Island, but the problem always persists.

    Researchers from the Louisiana Universities Marine Consortium just spent a week measuring dissolved oxygen concentrations off the coasts of Louisiana and Texas to determine how big the dead zone is this year. And they found that it is about 5,800 square miles, or roughly, the size of the state of Connecticut.

    Author(s): Alexis Baldera

  • Concise review of green algal genus Ulva Linnaeus

    The oldest green algal genus Ulva has wide spread distribution to all the continents. The distromatic and monostromatic thallus both now form single taxa based on ITS rDNA and rbcL gene sequencing. Ulva is known to occupy several ecological niches including fresh and marine (intertidal and subtidal) habitats, attributed to its tolerance to key determinants such as light, temperature, salinity etc. The genus is perceived as model system to study life-cycle, morphogenesis and development from simple to complex multicellularity. The life cycle is isomorphic and biphasic type, knowledge of which is important in developing viable cultivation techniques. The culture is being attempted by photo-bioreactor, land based and open sea farming which registered 1,500 tones dry annum-1 biomass production. The understanding of scientific basis for eutrophication-driven green tide events is of paramount importance for coastal ecosystem management. The studies related to cross – kingdom cross – talk between Ulva and surrounding microbe are recently undertaken through high-throughput techniques to understand their role in growth, development and morphogenesis. The several regional species are rich in vital nutrients thus qualify in functional food sector, but recent research is poised to develop bio-refinery model for complete utilization of feedstock.

    Author(s): Vaibhav Mantri, Mudassar Anisoddin Kazi , Nikunj B. Balar, Vishal Gupta, Tejal Gajaria

  • Comprehensive Oilgae Report - Energy from Algae: Products, Market, Processes & Strategies

    Algae fuels present an exciting opportunity. There is a strong view among industry professionals that algae represent the most optimal feedstock for biofuel production in the long run. It is also widely accepted that algae alone - and no other bio-feedstock - have the ability to replace the entire global fossil fuel requirements. Such a significant opportunity has resulted in companies both large and small investing in algal energy.

    Algae present multiple possibilities to fuel end-products - biodiesel, ethanol, methane, jet fuel, biocrude and more - via a wide range of process routes. Each of these process routes presents its own set of opportunities, parameters, dynamics and challenges. 

    Efforts into algae fuel research have accelerated in the past few years. As of mid 2010, about hundred companies and over a hundred universities have begun serious exploratory effects into algae fuels. 

    All these efforts will benefit enormously if a comprehensive resource is available that brings them up-to-date on the various critical aspects of the industry, status of past and on-going efforts, and critical data for assessing the technical and economic feasibility of algae fuels. Such a comprehensive resource has teh potential to save many months of research and analysis. 

    The Comprehensive Oilgae Report was developed to satisfy this clear need.

    The Comprehensive Oilgae Report is the most detailed report dealing with all aspects of the algae fuel industry. The report is divided into four main sections:

    • Concepts and Cultivation
    • Diverse Energy Products from Algae
    • Processes & Challenges
    • Industry & Market Information

    Each section provides in-depth information, details and updates on the most critical aspects relevant to it.

    The objective of the Comprehensive Oilgae Report is to facilitate tangible steps for an algae fuel venture. The emphasis hence is on providing practical data, updates and insights.

    In addition, the report has made special efforts in identifying the core challenges faced in each aspect of the algae fuels value chain. It also provides inputs on the current efforts and possible solutions to overcome these challenges.

    The report has been developed with over two years of in-depth research, and has been developed with inputs from biofuel industry experts, biotechnology researchers, and professioals who have been constantly interacting with the algae fuels industry for over four years.

    The Comprehensive Oilgae Report will be an invaluable guide to those keen on venturing into one of the most exciting renewable energy domains. 

    Author(s):

  • Composition and spatio temporal variability of the epiphytic macroalgal assemblage of Fucus vesiculosus Linnaeus at Clare Island, Mayo, western Ireland

    The composition and the patterns of spatial and temporal variability of the epiphytic assemblages of Fucus vesiculosus of Clare Island, on the western coast of Ireland, were investigated for an annual cycle. Specimens of Fucus were collected on seven sampling dates from three sites of the island (Portlea, Kinnacorra and Portnakilly). Data of cover of the most common epiphytic species were collected and analysed by multivariate and univariate techniques. Elachista fucicola, Polysiphonia lanosa, Porphyra umbilicalis, Spongonema tomentosum and Ulva compressa were the most common species. Spatial and temporal variation was detected both for the whole assemblage and for the most abundant species. In general, the assemblage was quantitatively more abundant and diverse in spring–summer than in autumn–winter. In spring–summer, there was a clear differentiation among the assemblage of Portnakilly and the assemblages of the other two sites. Individual species were also generally more abundant in spring – summer and their distribution at the three sites was often not consistent in time; P. lanosa was the only epiphyte for which a consistent effect of site was found. Spatial variation on a scale of meters to tens of meters was the most striking pattern of distribution of the epiphytic assemblage; significant effects related to this spatial scale were detected both for the whole assemblage and for individual species. Phenological patterns of the epiphytic species determining availability of propagules and limited dispersal, leading to aggregated patterns of distribution, are considered the main factors responsible of such patchiness. The importance of the incorporation of small spatial scales in sampling designs analysing the distributional patterns of epiphytic assemblages is discussed.

    Author(s): Fabio Rindi, Michael D. Guiry

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