U.S. flag

An official website of the United States government

PubAg

Main content area

Search

13  Search Results

1 - 13 of 13
Number of results to display per page

Search Results

1. Approach deliberation for source identification of sedimentary organic matters via comparing freshwater lakes with multi-ecotypes

Author:
Xu, Xiaoguang; Li, Wei; Deng, Hui; Fujibayashi, Megumu; Nomura, Munehiro; Nishimura, Osamu; Wang, Guoxiang
Source:
The Science of the total environment 2019 v.649 pp. 327-334
ISSN:
0048-9697
Subject:
Bacillariophyceae; Chlorophyta; Cyanobacteria; Miozoa; Nelumbo; Nymphoides; Phragmites; Trapa; bacteria; biomarkers; ecotypes; eutrophication; fatty acid composition; fatty acids; freshwater ecosystems; freshwater lakes; microalgae; organic matter; plants (botany); sediments; stable isotopes; statistical models; China; Japan
Abstract:
... Despite of the importance of understanding the sediment quality for lacustrine management, the source evaluation of sedimentary organic matter (SOM) in freshwater lakes is still insufficient. In this study, two shallow eutrophic lakes of Lake Taihu, China and Lake Izunuma, Japan were systematically investigated. Results of fatty acid profiles demonstrated that a wide range of organic matters, vary ...
DOI:
10.1016/j.scitotenv.2018.08.236

2. Biological sources of sedimentary organic matter in Neoproterozoic–Lower Cambrian shales in the Sichuan Basin (SW China): Evidence from biomarkers and microfossils

Author:
Wang, Ning; Li, Meijun; Hong, Haitao; Song, Daofu; Tian, Xingwang; Liu, Peng; Fang, Ronghui; Chen, Guo; Wang, Maolin
Source:
Palaeogeography, palaeoclimatology, palaeoecology 2019 v.516 pp. 342-353
ISSN:
0031-0182
Subject:
Bacillariophyceae; Cambrian period; Cyanobacteria; Ediacaran period; Miozoa; Pelagophyceae; Rhizobiales; algae; ancestry; basins; biomarkers; carbon; methane; methanotrophs; microfossils; organic matter; shale; stable isotopes; China
Abstract:
... Study of the occurrence and formation of sedimentary organic matter in the Sichuan Basin, southern China, provides valuable insights into the biological sources and compositions of Neoproterozoic to Lower Cambrian shales. Rock samples from two sets of shales in the Sichuan Basin and adjacent areas, including the Ediacaran Doushantuo shale and the Lower Cambrian Qiongzhusi shale in the Gaoshiti-Mox ...
DOI:
10.1016/j.palaeo.2018.12.012

3. Different ecological mechanisms lead to similar grazer controls on the functioning of periphyton Antarctic and sub-Antarctic communities

Author:
Valdivia, Nelson; Pardo, Luis M.; Macaya, Erasmo C.; Huovinen, Pirjo; Gómez, Iván
Source:
Progress in oceanography 2019 v.174 pp. 7-16
ISSN:
0079-6611
Subject:
Bacillariophyceae; Chlorophyta; Cyanobacteria; Fissurellidae; Miozoa; Phaeophyceae; biocenosis; chlorophyll; ecosystems; grazing; habitats; herbivores; littoral zone; models; periphyton; primary productivity; Antarctic region; Antarctica; Argentina
Abstract:
... The processes underpinning the differences between Antarctic and sub-Antarctic ecological communities are still unclear. Dispersal, drift, speciation, and abiotic environmental filtering have been considered to explain these differences; biotic interactions, however, have received less attention. Antarctic intertidal assemblages of macrobenthic grazers are characterised by numerically abundant pop ...
DOI:
10.1016/j.pocean.2018.01.008

4. Dynamics of Species and Size Structures of Phytoplankton at Different Levels of Bottom-Up and Top-Down Effects in Experimental Conditions

Author:
Sakharova, E. G.; Feniova, I. Yu.; Gorelysheva, Z. I.; Rzepecki, M.; Kostshevska-Shlakovska, I.; Krylov, A. V.; Zilitinkevicz, N. S.
Source:
Contemporary problems of ecology 2019 v.12 no.3 pp. 245-253
ISSN:
1995-4255
Subject:
Bacillariophyceae; Chlorophyta; Cyanobacteria; Miozoa; algae; eutrophication; fish; phytoplankton; zooplankton
Abstract:
... An experimental study of the impacts of trophic conditions and the activity of zooplankton and fish on the phytoplankton structure has shown that, at the beginning of the experiment, the species and size structures of algae were dependent on the N : P ratio. This parameter causes the differences in phytoplankton structures between mesotrophic and eutrophic conditions so that, in mesotrophic condit ...
DOI:
10.1134/S1995425519030119

5. Effects of different culture periods of commercial invasive red alga Kappaphycus alvarezii (Doty) Doty on plankton community structures in tropical marine environment, Southeast coast of India

Author:
Rajaram, R.; Rameshkumar, S.
Source:
Regional studies in marine science 2019 v.32 pp. 100906
ISSN:
2352-4855
Subject:
Bacillariophyceae; Copepoda; Cyanobacteria; Kappaphycus alvarezii; Miozoa; analysis of variance; biochemical oxygen demand; chlorophyll; coasts; community structure; crop yield; farming systems; gross primary productivity; invasive species; marine environment; monsoon season; net primary productivity; nitrates; pH; phytoplankton; population density; salinity; species diversity; India
Abstract:
... The commercial invasive red alga Kappaphycus alvarezii was cultivated by floating raft technique for the assessment of crop yields, growth rates and their impacts on the plankton community related to hydrobiological parameters in the Munakadu coast, Southeastern India for the period of one year from February 2016 to January 2017. The ANOVA results showed that the crop yield and daily growth rate o ...
DOI:
10.1016/j.rsma.2019.100906

6. Feeding rates and prey selection of the invasive Asian clam, Corbicula fluminea, on microplankton in the Columbia River, USA

Author:
Bolam, Benjamin A.; Rollwagen-Bollens, Gretchen; Bollens, Stephen M.
Source:
Hydrobiologia 2019 v.833 no.1 pp. 107-123
ISSN:
0018-8158
Subject:
Bacillariophyceae; Corbicula fluminea; Cyanobacteria; Miozoa; clams; community structure; food webs; ingestion; predation; rivers; Columbia River; Europe; South America; United States
Abstract:
... The Asian clam, Corbicula fluminea, was introduced into North America in the 1920s—first observed in the Columbia River—and has expanded its range across the continent and into South America and Europe, yet little is known about its ecology and potential to impact food webs. To evaluate prey selectivity and feeding rates of C. fluminea, we conducted laboratory feeding experiments using water from ...
DOI:
10.1007/s10750-019-3893-z

7. Light-adaptive state transitions in the Ross Sea haptophyte Phaeocystis antarctica and in dinoflagellate cells hosting kleptoplasts derived from it

Author:
Stamatakis, Kostas; Broussos, Panayiotis-Ilias; Panagiotopoulou, Angeliki; Gast, Rebecca J.; Pelecanou, Maria; Papageorgiou, George C.
Source:
Biochimica et biophysica acta 2019 v.1860 no.1 pp. 102-110
ISSN:
0005-2728
Subject:
Bacillariophyceae; Chlorophyta; Cyanobacteria; Miozoa; Phaeocystis; Rhodophyta; absorption; algae; amino acids; autotrophs; chlorophyll; circular dichroism spectroscopy; fluorescence; kleptoplasts; photosynthesis; ultraviolet radiation; Antarctica
Abstract:
... Light state transitions (STs) is a reversible physiological process that oxygenic photosynthetic organisms use in order to minimize imbalances in the electronic excitation delivery to the reaction centers of Photosystems I and II, and thus to optimize photosynthesis. STs have been studied extensively in plants, green algae, red algae and cyanobacteria, but sparsely in algae with secondary red alga ...
DOI:
10.1016/j.bbabio.2018.11.016

8. Phytoplankton evolution during the creation of a biofloc system for shrimp culture

Author:
Llario, F.; Rodilla, M.; Escrivá, J.; Falco, S.; Sebastiá-Frasquet, M.-T.
Source:
International journal of environmental science and technology 2019 v.16 no.1 pp. 211-222
ISSN:
1735-1472
Subject:
Bacillariophyceae; Cyanobacteria; Miozoa; aquaculture systems; biofloc technology; biomarkers; community structure; computer software; heterotrophs; high performance liquid chromatography; light intensity; microalgae; microscopy; monitoring; net primary productivity; nutritive value; phytoplankton; pigments; shrimp; shrimp culture; toxins; water quality
Abstract:
... Microalgae play a key role in the dynamics of biofloc technology aquaculture systems. Some phytoplankton groups, such as diatoms, are desired for their high nutritional value and contribution to water quality. Other groups, such as cyanobacteria, are undesired because of their low nutritional value and capacity of producing toxins. So, monitoring the phytoplankton community structure and successio ...
DOI:
10.1007/s13762-018-1655-5

9. Phytoplankton response to climate changes and anthropogenic activities recorded by sedimentary pigments in a shallow eutrophied lake

Author:
Zhang, Hanxiao; Huo, Shouliang; Yeager, Kevin M.; He, Zhuoshi; Xi, Beidou; Li, Xiaochuang; Ma, Chunzi; Wu, Fengchang
Source:
The Science of the total environment 2019 v.647 pp. 1398-1409
ISSN:
0048-9697
Subject:
Bacillariophyceae; Chlorophyta; Cyanobacteria; Miozoa; air temperature; algae; anthropogenic activities; chlorophyll; climate; climate change; lakes; models; phosphorus; phytoplankton; pigments; primary productivity; sediments; variance; China
Abstract:
... Studies that address the potential effects of climate and anthropogenic activities on lacustrine phytoplankton succession are scarce in the shallow lakes. In the present work, the succession of phytoplankton community inferred from sedimentary pigments has been investigated; the impacts of climate and anthropogenic activities on the succession have been evaluated by the generalized additive models ...
DOI:
10.1016/j.scitotenv.2018.08.081

10. Relationship between seasonal variations of primary production, abiotic factors and phytoplankton composition in the coastal zone of the south-eastern part of the Baltic Sea

Author:
Kudryavtseva, Elena; Aleksandrov, Sergey; Bukanova, Tatiana; Dmitrieva, Olga; Rusanov, Igor
Source:
Regional studies in marine science 2019 v.32 pp. 100862
ISSN:
2352-4855
Subject:
Bacillariophyceae; Chlorophyta; Cyanobacteria; Miozoa; ammonium nitrogen; biomass; coasts; environmental factors; eutrophication; latitude; nitrates; nutrients; organic matter; phosphates; photosynthesis; phytoplankton; primary productivity; runoff; seasonal variation; spring; summer; Baltic Sea
Abstract:
... Seasonal variations in marine primary production (PP) in the coastal zone of the south-eastern part of the Baltic Sea were studied between April 2008 and April 2009. The spring PP maximum was observed to be limited by the concentration of nitrates. Following a decrease in photosynthetic consumption of nutrients, an increase in ammoniacal nitrogen due to the decomposition of organic matter and conc ...
DOI:
10.1016/j.rsma.2019.100862

11. The occurrence of isorenieratane and 24-n-propylcholestanes in Paleogene lacustrine source rocks from the Dongying Depression, Bohai Bay Basin: Implications for bacterial sulfate reduction, photic zone euxinia and seawater incursions

Author:
Xu, Huiyuan; George, Simon C.; Hou, Dujie
Source:
Organic geochemistry 2019 v.127 pp. 59-80
ISSN:
0146-6380
Subject:
Bacillariophyceae; Botryococcus; Chlorobiaceae; Chromatiaceae; Cyanobacteria; Eocene epoch; Miozoa; algae; alkanes; anaerobic conditions; bacterial communities; basins; biomarkers; euphotic zone; hydrogen sulfide; isoprenoids; lakes; organic matter; petroleum; rocks; salinity; seawater; sulfate-reducing bacteria; sulfates; sulfur; surface water; transgressive segregation; China
Abstract:
... Lacustrine organic-rich source rocks (shales and mudstones) were examined to assess the depositional environment and organic input sources of the third and fourth members of the Eocene Shahejie Formation, Bohai Bay Basin, China. Major organic contributions to the Shahejie Formation from dinoflagellates, diatoms, Botryococcus and marine pelagophyte/chrysophyte algae were determined using n-alkane d ...
DOI:
10.1016/j.orggeochem.2018.11.008

12. The role of mixing in controlling resource availability and phytoplankton community composition

Author:
Villamaña, Marina; Marañón, Emilio; Cermeño, Pedro; Estrada, Marta; Fernández-Castro, Bieito; Figueiras, Francisco G.; Latasa, Mikel; Luis Otero-Ferrer, Jose; Reguera, Beatriz; Mouriño-Carballido, Beatriz
Source:
Progress in oceanography 2019
ISSN:
0079-6611
Subject:
Bacillariophyceae; Cyanobacteria; Hemiaulus; Miozoa; biomass; community structure; environmental factors; light intensity; marine environment; microstructure; mixing; nitrogen; nitrogen fixation; nutrient availability; nutrient content; photosynthesis; phytoplankton; pigments; regression analysis; subtropics; turbulent flow; Iberian Peninsula; Indian Ocean
Abstract:
... We investigate the role of mixing, through its effect on nutrient and light availability, as a driver of phytoplankton community composition in the context of Margalef́s mandala. Data on microstructure turbulence, irradiance, new nitrogen supply and phytoplankton composition were collected at 102 stations in three contrasting marine environments: the Galician coastal upwelling system of the northw ...
DOI:
10.1016/j.pocean.2019.102181

13. Variation in phytoplankton pigment composition in relation to mixing conditions in temperate South-Central Chilean lakes

Author:
Vannieuwenhuyze, Wim; Van de Vyver, Evelien; Van Wichelen, Jeroen; Vanormelingen, Pieter; Van Nieuwenhuyze, Wim; Daveloose, Ilse; De Jong, Rixt; De Blok, Reinhoud; Urrutia, Roberto; Tytgat, Bjorn; Verleyen, Elie; Vyverman, Wim
Source:
Limnologica 2019 v.79 pp. 125715
ISSN:
0075-9511
Subject:
Bacillariophyceae; Cyanobacteria; Miozoa; algae; altitude; biomarkers; chlorophyll; euphotic zone; freshwater lakes; light intensity; limnology; lutein; mixing; nutrient content; phytoplankton; primary productivity; radiation resistance; silica; summer; thermal stability; violaxanthin; volcanoes; watersheds; zeaxanthin; Chile
Abstract:
... Thermal lake properties are sensitive to changes in windiness and precipitation, and affect the physical and chemical properties of the water column, which in turn control phytoplankton dynamics and primary production. We assessed the use of phytoplankton pigment profiling as a potential indicator of stratification conditions in temperate lakes in South-Central Chile. Spring and early summer phyto ...
DOI:
10.1016/j.limno.2019.125715