Dissolution of coccolithophorid calcite by microzooplankton and copepod grazing

Abstract. Independent of the ongoing acidification of surface seawater, the majority of the calcium carbonate produced in the pelagial is dissolved by natural processes above the lysocline. We investigate to what extent grazing and passage of coccolithophorids through the guts of copepods and the food vacuoles of microzooplankton contribute to calcite dissolution. In laboratory experiments where the coccolithophorid Emiliania huxleyi was fed to the rotifer Brachionus plicatilis, the heterotrophic flagellate Oxyrrhis marina and the copepod Acartia tonsa, calcite dissolution rates of 45–55%, 37–53% and 5–22% of ingested calcite were found. We ascribe higher loss rates in microzooplankton food vacuoles as compared to copepod guts to the strongly acidic digestion and the individual packaging of algal cells. In further experiments, specific rates of calcification and calcite dissolution were also measured in natural populations during the PeECE III mesocosm study under differing ambient pCO2 concentrations. Microzooplankton grazing accounted for between 27 and 70% of the dynamic calcite stock being lost per day, with no measurable effect of CO2 treatment. These measured calcite dissolution rates indicate that dissolution of calcite in the guts of microzooplankton and copepods can account for the calcite losses calculated for the global ocean using budget and model estimates.

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Observation: A Vehicle for Generating Information between Partners in Problem Solving

Journal of Education ◽

10.1177/002205747615900406 ◽

1976 ◽

Vol 159 (4) ◽

pp. 49-61

Author(s):

Jonathan Clark ◽

Pierre Johannet

Keyword(s):

Problem Solving ◽

Direct Experience ◽

Natural Processes ◽

Problem Resolution ◽

New Perspective ◽

The Individual ◽

Search For Information ◽

Direct Encounter

The individual employs two basic sources for perception: direct experience and the interpretations of the culture. Natural processes can lead individuals who seek to resolve problems together to excessive reliance on socialized perceptions while overlooking valuable direct experience. As the partners establish assumptions, they may prematurely cease the search for information which could lead to a new perspective on the problem. A cycle is mobilized in which information generated by direct encounter fails to check powerful assumptions. The authors offer an observational model through which partners share both their experiences and their interpretations of these experiences. The model is designed to reduce the power of assumptions and to restore the influence of direct experience in problem resolution.

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Individual growth of Heleobia piscium in natural populations (Gastropoda: Cochliopidae) from the multiple use natural Reserve Isla Martin Garcia, Buenos Aires, Argentina

Brazilian Journal of Biology ◽

10.1590/s1519-69842008000300020 ◽

2008 ◽

Vol 68 (3) ◽

pp. 617-621 ◽

Cited By ~ 5

Author(s):

SM. Martin

Keyword(s):

Buenos Aires ◽

Natural Populations ◽

Dynamic Structure ◽

Reproductive Period ◽

Individual Growth ◽

Growth Equation ◽

Multiple Use ◽

Natural Reserve ◽

Drainage Channels ◽

The Individual

The present work analyses the individual growth of Heleobia piscium in natural conditions in coastal drainage channels of the Multiple Use Natural Reserve Isla Martín García, Buenos Aires, Argentina. Isla Martín García is located in the Upper Río de la Plata, to the south of the mouth of the Uruguay river (34° 11' 25" S and 58° 15' 38" W). Monthly collections were made from July 2005 to July 2006 in the eastern part of the island (Arena Beach). The population of H. piscium showed a complex and dynamic structure of sizes during a long period of the annual cycle. Two cohorts could be detected. The Bertalanffy growth equation was: Lt = 6 (1-e -1.85 (t+0.38)) and Lt = 3.9 (1-e -0.19 (t+4.84)) for cohorts 1 and 2, respectively. The pattern of population growth displayed a staggered model, where the greatest growth is observed during the summer. The reproductive period occurred during six months, from the beginning of summer to middle of fall. Based on only one reproductive effort, this pattern is not similar to that of other cogeneric species already studied.

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Patterns of Genetic Diversity in the Marine Heterotrophic Flagellate Oxyrrhis marina (Alveolata: Dinophyceae)

Protist ◽

10.1016/j.protis.2009.11.003 ◽

2010 ◽

Vol 161 (2) ◽

pp. 212-221 ◽

Cited By ~ 28

Author(s):

Chris D. Lowe ◽

David J.S. Montagnes ◽

Laura E. Martin ◽

Phillip C. Watts

Keyword(s):

Genetic Diversity ◽

Heterotrophic Flagellate ◽

Oxyrrhis Marina

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Understanding the trends and controlling factors of Indian Ocean acidification

10.5194/egusphere-egu21-14298 ◽

2021 ◽

Author(s):

Kunal Madkaiker ◽

Vinu Valsala

Keyword(s):

Indian Ocean ◽

Spatial Variability ◽

Dissolved Inorganic Carbon ◽

Total Alkalinity ◽

Global Ocean ◽

Strong Negative Correlation ◽

Chemical Balance ◽

Factors Affecting ◽

Water Ph ◽

The Individual

The Indian Ocean (IO) is witnessing acidification of its surface waters as a consequence of the continuous rising of atmospheric CO2 concentration thus disrupting the biological and chemical balance of the ecosystem in the region. The basin wide spatial variability of biogeochemical properties induces spatial variability of surface water pH. This study investigates the seasonality and trends of surface pH over the IO bioprovinces and regionally assesses the individual contribution of the factors affecting its variability. Simulations from global ocean models (OTTM and ROMS) coupled with suitable biogeochemical modules were validated with pH observations over the basin, and used to discern the regional response of pH seasonality (1990-2010) and trend (1961-2010) to changes in ocean temperature (SST), Dissolved Inorganic Carbon (DIC), Total Alkalinity (ALK) and Salinity (S). DIC and SST are the major contributors to the seasonal variability of pH in almost all bioprovinces consistent in both model simulations. The acidification in IO basin of 0.0675 units during 1961-2010 is attributed to 69.28% contribution of DIC followed by 13.82% contribution of SST. For most of the regions DIC remains a dominant contributor to changing trend in pH except for the Northern Bay of Bengal and Around India (NBoB-AI) region, wherein pH trend is dominated by ALK (55.6%) and SST (16.8%). The interdependence of SST and S over ALK is significant in modifying the carbonate chemistry and biogeochemical dynamics of NBoB-AI and a part of tropical, subtropical IO. The strong negative correlation between SST and pH infers the increasing risk of acidification in the bioprovinces with the rising SST.This study is an attempt to identify the regional influencers of pH variability so that adequate mitigation action can be planned and the acidification can be decelerated in near future.

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The Evolutionary Dynamics of Genetic Incompatibilities Introduced by Duplicated Genes in Arabidopsis thaliana

Molecular Biology and Evolution ◽

10.1093/molbev/msaa306 ◽

2020 ◽

Author(s):

Wen-Biao Jiao ◽

Vipul Patel ◽

Jonas Klasen ◽

Fang Liu ◽

Petra Pecinkova ◽

...

Keyword(s):

Evolutionary Dynamics ◽

Natural Populations ◽

Population History ◽

Duplicated Genes ◽

Genetic Incompatibility ◽

Additional Gene ◽

Genomic Changes ◽

Gene Copies ◽

Geographic Origins ◽

The Individual

Abstract Although gene duplications provide genetic backup and allow genomic changes under relaxed selection, they may potentially limit gene flow. When different copies of a duplicated gene are pseudofunctionalized in different genotypes, genetic incompatibilities can arise in their hybrid offspring. Although such cases have been reported after manual crosses, it remains unclear whether they occur in nature and how they affect natural populations. Here, we identified four duplicated-gene based incompatibilities including one previously not reported within an artificial Arabidopsis intercross population. Unexpectedly, however, for each of the genetic incompatibilities we also identified the incompatible alleles in natural populations based on the genomes of 1,135 Arabidopsis accessions published by the 1001 Genomes Project. Using the presence of incompatible allele combinations as phenotypes for GWAS, we mapped genomic regions that included additional gene copies which likely rescue the genetic incompatibility. Reconstructing the geographic origins and evolutionary trajectories of the individual alleles suggested that incompatible alleles frequently coexist, even in geographically closed regions, and that their effects can be overcome by additional gene copies collectively shaping the evolutionary dynamics of duplicated genes during population history.

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From cells to globe: approaching the dynamics of DMS(P) in the ocean at multiple scales

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f04-030 ◽

2004 ◽

Vol 61 (5) ◽

pp. 673-684 ◽

Cited By ~ 73

Author(s):

Rafel Simó

Keyword(s):

Multiple Scales ◽

Cellular Level ◽

Trophic Levels ◽

Global Ocean ◽

Surface Mixed Layer ◽

Sulfur Transfer ◽

Ocean Level ◽

Ecosystem Level ◽

Major Carrier ◽

The Individual

Major advances in dimethylated sulfur research are being made by approaching its dynamics at multiple scales. At the molecular to cellular level, single-cell techniques in molecular biology allow us to identify the microbes involved in cycling of dimethylated sulfur. Also, we find that dimethylsulfoxide (DMSO) is as ubiquitous as dimethyl sulfoniopropionate (DMSP) in marine plankton, which supports the recent suggestion that both compounds are involved in coping with oxidative stress. At the community level, there is recent evidence for the role of DMSP as a major carrier in organic sulfur transfer and cycling through trophic levels, from phytoplankton to bacteria and to zooplankton through herbivore protozoans. As a consequence, the food web dynamics drive the oceanic emission of atmospheric sulfur. At the ecosystem level, the diverse and intricate effects of the physicochemical setting (light, wind, nutrients) on the oceanic cycling of dimethylated sulfur are being uncovered. A proposed shortcut to detailed understanding of the individual processes presents the depth of the surface mixed layer as the variable that integrates most of the environmental effects and serves for predicting dimethylsulfide (DMS) concentrations, even at the global ocean level. This opens the door to assessing the strength of the DMS biogeophysical system as a climate regulator.

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Pawilony bioniczne

BUILDER ◽

10.5604/01.3001.0013.3332 ◽

2019 ◽

Vol 258 (1) ◽

pp. 26-28

Author(s):

Anna Nowak ◽

Wiesław Rokicki

Keyword(s):

Fibonacci Sequence ◽

Natural World ◽

Digital Tools ◽

Biological Processes ◽

Structural Elements ◽

Biological Models ◽

Natural Processes ◽

Advanced Knowledge ◽

The Individual ◽

Advanced Computer

INSPIRATIONS OF NATURE IN ARCHITECTURE. BIONIC PAVILIONS. The search for bionics is an interesting design notion, where the form of architectural objects is not only inspired by the aesthetics or patterns found in nature, but how its shape is reproduced by the natural processes of morphogenesis. Depending on how various patters in nature are replicated, a number of bionic modeling can be observed. The design based on the principles of forming natural structures requires some understanding of the ongoing processes and their changes. Thanks to the improvement of generative design methods allowing for the advanced knowledge in the field of technology to build the individual structural elements, a structural replication and analysis of biological processes is possible. The creation of mathematical models is an attempt to describe the forms found in the natural world, in particular the aspects of the morphogenesis. The Voronoi diagrams, or the Fibonacci sequence, which are increasingly used as a method of the discretization of the surface, deserve special consideration among the mentioned patterns found in nature. Digital tools play an important role in this process through the application of appropriate algorithms and advanced computer programs, but also experimental activities geared to building prototype solutions. The design of complicated spatial forms under different aspects is also aimed at searching for optimized technical and material solutions, in which unnecessary geometry is being eliminated. The transfer of biological models into architecture also applies to functional processes and systems found in nature in terms of shaping the coating elements. This paper is dedicated to the presentation of the completed experimental pavilions, which were created based on the bionic ideas, where the search for the multifunctional materials seems to be particularly important and could in turn revolutionize the building industry.

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Taxonomic and conservation implications of ecological speciation in Nesospiza buntings on Tristan da Cunha

Bird Conservation International ◽

10.1017/s095927090800004x ◽

2008 ◽

Vol 18 (1) ◽

pp. 20-29 ◽

Cited By ~ 6

Author(s):

Peter G. Ryan

Keyword(s):

Species Conservation ◽

Natural Populations ◽

Morphological Diversity ◽

Ecological Speciation ◽

Conservation Priority ◽

Evolutionary Processes ◽

Natural Processes ◽

Tristan Da Cunha ◽

Conservation Implications

AbstractIn addition to protecting species, conservation also includes the maintenance of evolutionary processes, but this aspect is often overlooked. Nesospiza buntings provide a good case study of the need to conserve evolutionary processes. They are endemic to the South Atlantic Tristan da Cunha archipelago, and traditionally have been treated as two species, with each having different subspecies on Nightingale and Inaccessible Islands. Both species are listed as Vulnerable because of their small ranges (<20 km2) and the threat posed by the possible introduction of alien organisms such as mice or rats. The two species differ markedly in size, especially bill size, related to dietary differences. However, recent research suggests that morphological diversity evolved independently on Nightingale and Inaccessible Islands, necessitating a revision of the taxonomy within the genus. I recommend that five taxa be recognized, with two endemic to Nightingale and three to Inaccessible Island. N. wilkinsi and N. questi on Nightingale are well-defined species, but there is considerable hybridization between taxa on Inaccessible Island. These three taxa may be incipient species, but are perhaps best treated as subspecies: N. acunhae acunhae, N. a. dunnei and N. a. fraseri (nom. nov.). All three species qualify as threatened, with N. acunhae and N. questi Vulnerable and N. wilkinsi Endangered. With fewer than 200 individuals, N. wilkinsi has one of the smallest natural populations of any bird. A reassessment of its population size is a conservation priority, following the 2001 storm that damaged many Phylica trees on Nightingale Island. Improved biosecurity quarantine measures are also needed for Nightingale Island. Care should be taken not to disrupt the natural processes occurring among bunting taxa on Inaccessible Island.

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HORDEIN VARIATION IN WILD (HORDEUM SPONTANEUM) AND CULTIVATED (H. VULGARE) BARLEY

Canadian Journal of Genetics and Cytology ◽

10.1139/g79-043 ◽

1979 ◽

Vol 21 (3) ◽

pp. 391-404 ◽

Cited By ~ 94

Author(s):

Hans Doll ◽

A. H. D. Brown

Keyword(s):

Linkage Disequilibrium ◽

Wild Species ◽

Storage Protein ◽

Natural Populations ◽

Hordeum Spontaneum ◽

Allele Frequencies ◽

Evolutionary Processes ◽

Highly Correlated ◽

The Individual ◽

Allozyme Loci

The storage protein hordein contains two major groups of polypeptides which are highly polymorphic in barley, and in its evolutionary progenitor Hordeum spontaneum Koch. Crosses between the two species showed that the complex electrophoretic phenotypes within the two groups of polypeptides are governed by codominant alleles at two corresponding loci, Hor-1 and Hor-2, which are moderately linked (11% ± 2). In natural populations of the wild species, the two complex hordein loci were much more polymorphic than the allozyme loci. Furthermore, the variation at these two loci was highly correlated so that individuals differ from one another at both loci much more frequently than expected from the allele frequencies at the individual loci. Considerable hordein variation was also present in Composite Cross XXI, and there was evidence of reassortment of patterns by the seventeenth generation. Thus the complex hordein loci, with their extreme diversity and linkage disequilibrium, are ideal markers for monitoring evolutionary processes in both natural, or composite cross populations.

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Cave airflow patterns control calcite dissolution rates within a cave stream: Blowing Springs Cave, Arkansas, USA

10.31223/osf.io/t7a4q ◽

2020 ◽

Author(s):

Matthew Covington ◽

Katherine Knierim ◽

Holly Young ◽

Josue Rodriguez ◽

Hannah Gnoza

Keyword(s):

Dissolution Rates ◽

Calcite Dissolution

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