Effects of phytoplankton blooms on the cycling of manganese and iron in coastal waters

Bays in coastal upwelling regions are physically driven and biochemically fueled by their interaction with open coastal waters. Wind-driven flow over the shelf imposes a circulation in the bay, which is also influenced by local wind stress and thermal bay–ocean density differences. Three types of bays are recognized based on the degree of exposure to coastal currents and winds (wide-open bays, square bays, and elongated bays), and the characteristic circulation and stratification patterns of each type are described. Retention of upwelled waters in bays allows for dense phytoplankton blooms that support productive bay ecosystems. Retention is also important for the accumulation of larvae, which accounts for high recruitment in bays. In addition, bays are coupled to the shelf ecosystem through export of plankton-rich waters during relaxation events. Ocean acidification and deoxygenation are a concern in bays because local extrema can develop beneath strong stratification.

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Seasonal variability of phytoplankton blooms in the coastal waters along the East coast of India

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprsarchives-xl-8-1065-2014 ◽

2014 ◽

Vol XL-8 ◽

pp. 1065-1071 ◽

Cited By ~ 3

Author(s):

T. Preethi Latha ◽

K. H. Rao ◽

E. Amminedu ◽

P. V. Nagamani ◽

S. B. Choudhury ◽

...

Keyword(s):

Fresh Water ◽

Bay Of Bengal ◽

Coastal Waters ◽

Algal Blooms ◽

East Coast ◽

Water Discharge ◽

Marine Ecosystem ◽

Chlorophyll Concentration ◽

Phytoplankton Blooms ◽

East Coast Of India

Bay of Bengal (BOB) is a semi enclosed tropical basin located in the north eastern part of the Indian Ocean with high influence of fresh water discharge from major rivers and rainfall. Bay of Bengal (BOB) is highly influenced by monsoons and represents a natural laboratory to study the effect of fresh water fluxes on the marine ecosystem. Bay of Bengal (BOB) is very low in productivity often with the observations of Phytoplankton Blooms. Phytoplankton blooms are one of the prominent features of biological variability in the coastal ecosystems such as estuaries, lagoons, bays, and tidal rivers with rapid production and accumulation of phytoplankton biomass in the ocean. These blooms usually respond to changing physical forcings originating in the coastal ocean like tides, currents and river runoff and to the atmospheric forcing like wind. These physical forcings have different timescales of variability, so algal blooms can be short-term episodic events, recurrent seasonal phenomena, or rare events associated with exceptional climatic or hydrologic conditions. Bloom events and their variability on spatial & temporal scales monitoring through field measurements is difficult. Based on this key hypothesis an effort is made to understand the seasonal and spatial variability of Phytoplankton Blooms along the East Coast of India. In this paper we present the bloom dynamics in their context to the chlorophyll concentration along with species composition and abundance in estuarine and near shore coastal waters of Godavari basin using Oceansat-2 Ocean Colour Monitor (OCM). The initial results revealed that the quasi permanent phytoplankton blooms initiates in the month of mid- February and evolves for a period of two months and then slowly starts decaying by the mid of May month. The results also stand as a base for the study of influence of Phytoplankton Blooms on the carbon flux estimations and bio-geo-chemical processes in the Bay of Bengal.

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Phytoplankton dynamics and Red Tides (1987-1997) in the Bulgarian Black Sea

Water Science & Technology ◽

10.2166/wst.1999.0378 ◽

1999 ◽

Vol 39 (8) ◽

pp. 27-36 ◽

Cited By ~ 7

Author(s):

Violeta Velikova ◽

Snejana Moncheva ◽

Daniela Petrova

Keyword(s):

Time Series ◽

Black Sea ◽

Coastal Waters ◽

Algal Biomass ◽

Phytoplankton Community ◽

Red Tides ◽

Phytoplankton Dynamics ◽

Phytoplankton Blooms ◽

High Productivity ◽

Open Sea

Time series of phytoplankton density, biomass and species composition in the Bulgarian Black Sea (specifically Varna Bay) are analysed. The main patterns of year-to-year fluctuations in the phytoplankton community controlled by natural and man-induced factors are discussed. Many indications lead to the conclusion that phytoplankton blooms have not become less frequent in comparison with the period of progressive eutrophication (1975-85), and there is a trend towards an increase in the number of blooming species involved. The community maintains the capacity to produce a lot of biomass. Areas of high productivity occur mainly in coastal waters. In open sea areas the level of algal biomass is higher than in the 80s. Irrespective of low silicate concentrations, in general the 90s are the period of diatom predomination.

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