Seasonal Distribution Of Phytoplankton Research Articles

Seasonal distribution of phytoplankton in river Gauthami-Godavari, Andhra Pradesh

The present study was investigated to evaluate the seasonal variability of phytoplankton species at the places Vruddha and Bhairavapalem along the stretch of river Godavari in Konaseema region, Andhra Pradesh. A total of 123 phytoplankton species were identified during the study period (2015-2017) in which diatoms contributes 91, dinoflagellates -26, Blue Green Algae-1 chlorphyceae-4. Dissimilarity in phytoplankton species composition was noticed in all seasons. Diatoms found as the dominant prevailing phytoplankton group in all seasons in terms of number of species and abundance. Diatom species viz., Coscinodiscus sp., Thalassiothrix sp., Skeletonema costatus were ubiquitous off Godavari estuary throughout the year. Diatoms are the most abundant group dominated in late winter and early spring bloom whereas dinoflagellates, dominate during the late spring blooms.

Effects of Environmental Parameters on the Seasonal Distribution of Phytoplankton in the Shallow Lake Ketence, Turkey

The seasonal distribution of the phytoplankton and their relationship with environmental parameters of Lake Ketence was studied with monthly intervals in two stations between October 2016 and September 2017. A total of 93 taxa in 8 divisions were identified, and 11 taxa in 4 different divisions (Chlorophyta, Bacillariophyta, Euglenozoa, Miozoa) dominated the phytoplankton in different periods of the study. Main nutrients (NO3-N, NO2-N, TP, Si), some other parameters (T, EC, Secchi disk depth), and organic content of the lake had strong impacts on the distribution of phytoplankton assemblages. Although biomass values varied and indicated very good to very poor water quality during the studied period, especially the prevalence of chlorophytes such as T. minimum which prefer high nutrient and euglenoids such as E. clavata, E. rubra, P. longicauda, and T. oblonga that grew extremely well under high organic content has confirmed that Lake Ketence is eutrophic.

Seasonal distribution of phytoplankton and environmental factors in the offshore waters of Dokdo: Comparison between 2018 and 2019

Seasonal distribution of phytoplankton and environmental factors in the offshore waters of Dokdo: Comparison between 2018 and 2019

Seasonal distribution of phytoplankton and its association with physico-chemical parameters in coastal waters of Malvan, west coast of India.

Malvan coast is one of the Marine Protected Area (MPA) of Maharashtra because of its rich coral reef and biodiversity. The study investigated on phytoplankton assemblage and their diversity with respect to physico-chemical parameters covering protected and unprotected area of Malvan coast. Physico-chemical parameters such as salinity, nitrite, nitrate, and ammonia did not display seasonality due to inadequate fresh water influx and allochthonous nutrient input. Positive correlation of phosphate (r=0.96, p<0.0001) and silicate (r=0.91, p<0.0001) with Total Suspended Solids (TSS) confirmed their autochthonous origin as a result of resuspension of bottom sediments during monsoon. A total of 57 phytoplankton species were identified mostly dominated by Bascillariophyceae (40 species), followed by Dinophyceae (9 species), Chlorophyceae (5 species), Cyanophyceae (2 species), and Dictyochophyceae (1 species) from Malvan coast. Canonical correspondence analysis (CCA) revealed that water temperature and TSS were the most significant parameters influencing the distribution and seasonal shift in phytoplankton species such as Skeletonema costatum and Chaetoceros sp. during pre-monsoon and Psedo-nitzschia sp., Streptotheca thamensis, Eucampia zodiacus, and Lithodesmium undulatum during post-monsoon. Silicate and phosphate had minor influence on phytoplankton distribution. Shannon-Wiener diversity index as a pollution index suggested that the study area was incipiently polluted except at bay stations. Despite of various human interventions the water quality and phytoplankton assemblage of this area has not reached to an alarming situation. The current study provides a valuable baseline data on phytoplankton assemblage from Malvan coast.

Seasonal Distribution of Phytoplankton in Riwada Reservoir, Visakhapatnam, Andhra Pradesh, India

The present study deals with seasonal variations, correlation coefficient and biodiversity indices of phytoplankton during April 2011 to March 2012 in the Riwada reservoir, Visakhapatnam, Andhra Pradesh, India. Sampling was performed at five stations during pre-monsoon, monsoon and post monsoon. There were a total of 57 genera belonging to four major groups i.e., Chlorophyceae (27 genera), Bacillariophyceae (14 genera), Cyanophyceae (13 genera) and Euglenophyceae (three genera). Maximum and minimum total phytoplankton population and percentages were recorded at station three in pre monsoon and at station two during monsoon. The maximum and minimum species richness (Menhinick index R2) were found to be 1.29 at station one and 1.10 at station three respectively. Maximum and minimum species diversity (H1) were found at station four (3.98) and station two (3.71). Maximum species evenness was recorded at stations one, being four and five; minimum species evenness was recorded at station two. Correlation coefficient matrix indicated significant positive relationship with water temperature, pH, transparency, biological oxygen demand and chlorides, negative relationship with electric conductivity, total solids, total dissolved solids, total hardness, dissolved oxygen, nitrates, sulphates and phosphates of water. The diversity indices showed that the reservoir have a well balanced phytoplankton community.

Impacts of restoration of an uncontrolled phosphogypsum dumpsite on the seasonal distribution of abiotic variables, phytoplankton, copepods, and ciliates in a man-made solar saltern

The restoration of an uncontrolled phosphogypsum landfill was investigated for its effects on the seasonal distribution of phytoplankton, ciliates, and copepods. Sampling was carried out monthly from September 2007 to August 2008 at four ponds of increasing salinity (A1, 41psu; A5, 46psu; A16, 67psu; and C31, 77psu) in the Sfax solar saltern (southeastern Tunisia). Physicochemical and biological analyses were carried out using standard methods. Results showed drastic reduction of phosphate input and greater diversity of phytoplankton, ciliates, and copepods than before restoration. Pennate diatoms and new ciliates, considered bio-indicators of less-stressed marine ecosystems, proliferated in the A1 pond for the first time after restoration. Copepods appeared to feed on a wide range of prey. Economically, removal of the 1.7 million m(3) of phosphate improved the quality of the site's salt production, enabling the salt company to receive the quality ISO 9001 accreditation.

Seasonal distribution of phytoplankton in the Aby lagoon system, Ivory Coast, West Africa

Seasonal variability of phytoplankton species composition, abundance and physical and chemical factors influencing phytoplankton dynamics were investigated in the Aby lagoon system, south-eastern Ivory Coast, covering the main climatic seasons in 2006–2007. Seasonal and spatial variability of nutrient concentrations in the system were influenced by freshwater inflow from the Bia and Tanoé rivers. The decrease in the salinity gradient in Aby Lagoon, which is permanently stratified during the long dry season, increased the bottom inputs of soluble reactive phosphate and soluble reactive silicate which, in combination with good light penetration during the long dry season, enhanced phytoplankton production in the system. During the rainy seasons, water discharges into the system washed phytoplankton biomass out, preventing the development of blooms. Overall, 192 taxa from eight phyla were recorded: Bacillariophyta (32%), Chlorophyta (31%), Cyanobacteria (23%), Euglenophyta (12%), Dinophyta (0.5%), Xanthophyta (0.5%), Chrysophyta (0.5%) and Rhodophyta (0.5%). During the long dry season, Cyanobacteria cells comprised >50% of the phytoplankton abundance. The main phytoplankton taxa responsible for this high abundance were Microcystis aeruginosa, Oscillatoria princeps, Pseudanabaena limnetica, Aphanizomenon sp. 2 and Anabaena planctonica.

Regional, vertical and seasonal distribution of phytoplankton and photosynthetic pigments in Lake Baikal

A 3-year phytoplankton study was carried out in Lake Baikal (Siberia) as part of the CONTINENT project and in conjunction with a 60-year long monitoring programme by the Irkutsk State University. A combination of microscopy and high performance liquid chromatography (HPLC) pigment analysis was used. All over the lake, the dominant functional group (by biovolume) was the vernal diatom blooms, due to the dominance of endemic Cyclotella species. Chlorophyll a (Chl a) was significantly highest at the Selenga and Barguzin inflows (2.39 ± 0.34 and 2.49 ± 0.18 nmol L–1, mean ± 95% CI, respectively) and higher in the South than in the North (1.43 ± 0.26 and 0.96 ± 0.13 nmol L−1). This variation of Chl a reflected changes in the phytoplankton composition. Diatoms and Chrysophyceae were the major contributors to the total Chl a except in the South (Chlorophyceae) and Selenga Delta (cyanobacterial picoplankton). There were also indications of species composition changes due to enhanced P-loading from the Selenga River. However, canonical analyses indicated that temperature and stratification were the major driving forces for regional distribution patterns and seasonal succession. It seems likely that further global warming will cause a shift in the species and group composition towards small cells at the expense of the large endemic diatom flora.

Ocean colour and the spatial and seasonal distribution of phytoplankton in the Barents Sea

The temporal and spatial distributions of phytoplankton biomass in polar seas are strongly influenced by physical factors, the most important of which are the light regime and mixing processes in the water masses. Field measurements and estimates for chlorophyll based on satellite data from the experimental Coastal Zone Color Scanner show that the distribution of chlorophyll concentrations in surface waters is closely related to the different water masses in the region. As expected, the highest chlorophyll-like concentrations are found in the coastal waters and in the Atlantic waters south of the Polar Front. Surface chlorophyll concentrations near the ice edge in the north are high during a short period following ice melting but decrease rapidly due to nutrient depletion. The intensity of this ice-edge bloom decreases with increasing latitude. The chlorophyll distribution patterns observed in satellite imagery are consistent with field observations,but remotesensing data provide additionalinformation because of their higher spatial resolution. Local phytoplankton blooms can be observed on the banks near Svalbard and Novaya Zemlya. Improved ocean colour satellites available in the near future will provide more frequent coverage and will allow more detailed studies of seasonal variations in phytoplankton distribution and primary production in this highly productive region.

Spatial and seasonal distribution of phytoplankton in an African Rift Valley lake (L. Albert, Uganda, Zaire)

An account is given of the seasonal succession and spatial distributionof phytoplankton derived from a one-year sampling programme (1961–62)on Lake Albert, a large African rift lake. There is evidence of regulationby both physical and nutrient factors. These are influenced by a markedseasonality of temperature/density stratification (temperature range 100 µg l-1), but those ofinorganic nitrogen are low and, with large depletions of silicate-silicon,may limit algal production. The diatom and cyanophyte components of thephytoplankton show different relationships to the seasonal cycle of limitedstratification and vertical mixing. There are possible relationships, bygrazing, to the described seasonal and spatial abundance of planktonicCladocera. Comparisons are made with other African lakes, especially LakeTurkana which is of similar shape and size and shows end to end polarizationof the aquatic biota.

Phytoplankton community structure and succession in a tropical estuarine complex (central west coast of India)

The seasonal distribution of phytoplankton in the Mandovi-Zuari estuarine complex (central west coast of India) from November 1979 to October 1980 is described. Of the 82 species of phytoplankton recorded, diatoms (63 species) showed an overwhelming predominance over dinoflagellates (14 species), blue-green algae (three species) and green algae (two species). Among the several factors affecting phytoplankton, the commencement of the south-west monsoon results in a drastic change in hydrographic conditions which are instrumental in the transformation of the phytoplankton population size and structure. The great variability in the ecosystem is amply illustrated by species succession.

濠の植物性〓の季節的消長

濠の植物性〓の季節的消長