Temperature and light effects on the seasonal succession of algal communities in shallow coastal lagoons

The regional differences in the composition of the phytoplankton assemblages in several coastal lagoons of the “Outer Delta of the Río Magdalena” (Caribbean coast of Colombia) were determined using microscopic counting and HPLC-pigment measurements. The study sites can be classified as 1) a group of limnic lagoons with relatively low (5.5-19 μg/l) chlorophyll a (chl a) concentrations and high inorganic suspension loading, 2) a group of brackish lagoons with high (62-90 μg/l) chl a concentrations and high amounts of organic seston, (two further lagoons form a transition between group 1 and 2, and 3) a fully marine Caribbean bay with very low (0.3 μg/l) chl a and seston concentrations. The regional variations in salinity of the lagoons are due to inflow of water from the Río Magdalena or to inflow of Caribbean Sea water. All lagoons are very shallow (less than 2 m) with small Secchi depths (20 to 30 cm). With the exception of the eutrophic brackish lagoons, where both methods indicated cyanobacteria to be the prevalent algal group, great discrepancies were encountered in all other study sites between the compositions of the algal communities obtained with both approaches. According to the microscopic analysis the phytoplankton of the marine Caribbean bay and the limnic and transient coastal lagoons consisted mainly (in several cases exclusively) of diatoms. The pigment analysis, on the other hand, indicated that cyanobacteria were the dominant algal group in all coastal lagoons, their percentage increased from the limnic over the transient to the brackish lagoons. Fractionated filtration of 14C-labelled phytoplankton revealed that algae of <5μm size in the coastal lagoons contributed 32-88% of the total radioactivity and that algae of >20μm size played only an insignificant role in primary production. Only in the Caribbean bay 14% of the 14CO2 was taken up by organisms >20μm. We assume that the small forms are greatly underrepresented in microscopic observations due to extreme difficulties in identification and counting caused by detritus and/or sediment loadings of the samples. We therefore believe that these small forms (probably mostly picoplanktonic cyanobacteria) are better represented by pigment analysis.

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Composition and structure of algal communities in a tributary stream of Lake Ontario

Canadian Journal of Botany ◽

10.1139/b72-205 ◽

1972 ◽

Vol 50 (8) ◽

pp. 1663-1674 ◽

Cited By ~ 16

Author(s):

J. W. Moore

Keyword(s):

Petromyzon Marinus ◽

Seasonal Succession ◽

Lake Ontario ◽

Hard Water ◽

Water Stream ◽

Algal Communities ◽

Southern Ontario ◽

Composition And Structure ◽

Planktonic Community ◽

New Occurrences

The composition and structure of epipelic and planktonic algal communities in Shelter Valley Creek, Ontario, was studied for 1 year. The overall assemblage consisted of 388 taxa of which 321 were Bacillariophyceae. On the sediments, seasonal succession and community structure was, with some exceptions, typical of a hard-water stream in the northern temperate zone. Taxa that occurred frequently throughout the year were Achnanthes minutissima Kütz., Cocconeis placentula var. euglypta (Ehr.) Cl., Gomphonema olivaceum var. balticum Cl., and Navicula tripunctata (O. F. Müller) Bory. The planktonic community was, for the most part, derived from the benthos. Herbivorous grazing by larval sea lamprey, Petromyzon marinus (Pisces: Cyclostomata) did not noticeably affect algal numbers in either the plankton or sediments.Sixty-six taxa are reported as new occurrences in southern Ontario.

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Seasonal Variation in Biomass and Production of the Macrophytobenthos in two Lagoons in the Southern Baltic Sea

Frontiers in Earth Science ◽

10.3389/feart.2020.542391 ◽

2021 ◽

Vol 8 ◽

Author(s):

Martin Paar ◽

Maximilian Berthold ◽

Rhena Schumann ◽

Sven Dahlke ◽

Irmgard Blindow

Keyword(s):

Primary Production ◽

Net Primary Production ◽

Coastal Lagoons ◽

Light Attenuation ◽

Seasonal Succession ◽

Trophic Levels ◽

Seasonal Development ◽

Nutrient Concentrations ◽

Eutrophic Lagoon ◽

The Impact

Baltic coastal lagoons are severely threatened by eutrophication. To evaluate the impact of eutrophication on macrophytobenthos, we compared the seasonal development in macrophytobenthic composition, biomass and production, water column parameters (light, nutrients), phytoplankton biomass and production in one mesotrophic and one eutrophic German coastal lagoon. We hypothesized that light availability is the main driver for primary production, and that net primary production is lower at a higher eutrophication level. In the mesotrophic lagoon, macrophytobenthic biomass was much higher with distinct seasonal succession in species composition. Filamentous algae dominated in spring and late summer and probably caused reduced macrophytobenthic biomass and growth during early summer, thus decreasing vegetation stability. Light attenuation was far higher in the eutrophic lagoon, due to high phytoplankton densities, explaining the low macrophytobenthic biomass and species diversity in every season. Areal net primary production was far lower in the eutrophic lagoon. The “paradox of enrichment” hypothesis predicts lower production at higher trophic levels with increased nutrient concentrations. Our results prove for the first time that this hypothesis may be valid already at the primary producer level in coastal lagoons.

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STRUKTUR KOMUNITAS MAKRO ALGA DI PESISIR PULAU KECAMATAN BULANG

SIMBIOSA ◽

10.33373/sim-bio.v3i2.282 ◽

2014 ◽

Vol 3 (2) ◽

Author(s):

Notowinarto Notowinarto ◽

Ramses Ramses ◽

Mulhairi Mulhairi

Keyword(s):

Community Structure ◽

Diversity Index ◽

Algal Species ◽

Algal Communities ◽

Marine Life ◽

Ph Values ◽

Abundance Patterns ◽

Coastal Marine ◽

Temperature Parameter ◽

Important Value Index

Bulang districts Batam Islands of Riau province (Riau Islands), its consists of many islands with as well as having the potential diversity of coastal marine life in particular kinds of macro algae or seaweed. Conducted research aimed to determine the structure of macro- algal communities in the intertidal zone islands. The results of the identification of algal species found 16 species are: the Order of Chlorophyceae as 6 spesies; Order Phaeophyceae as 2 spesies; and Order Rhodophyceae as 8 spesies. The community structure at the five stations showed the highest values were found in the island of dominance Cicir (D ' = 0.79) , uniformity index values on Tengah Island (E ' = 0.99) , while the island Balak had the highest diversity index (H ' = 0.88) , with the abundance patterns of population structure on the island is pretty good Central . Results of correlation analysis of regression between IVI types of algae with the conditions of environmental quality suggests that there is a significance (Fhit ˃ F table and the value of r = > 90 %) between IVI algae Halimeda sp and Cryptarachne polyglandulosa at each station with a temperature parameter surface (⁰C) , depth temperature (⁰C) and pH values. Keywords : Algae, Community Structure, Important Value Index.

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