Spatio-temporal Distribution Of Phytoplankton Research Articles

Biogeochemical Markers to Identify Spatiotemporal Gradients of Phytoplankton across Estuaries

The spatiotemporal distribution of phytoplankton in estuaries is indicative of processes and transport across the land–ocean aquatic continuum (LOAC). Estuaries, as biogeochemically and physically active systems, process large amounts of nutrients and organic matter influencing the transformation of ecological functions. The transformation of the water column drives variation in phytoplankton composition, biomass, and their spatial distribution. Understanding the dynamics of nutrients and organic matter is challenging, yet it provides a comprehensive insight into phytoplankton spatiotemporal distribution across estuaries. Multiple studies have been conducted to understand the spatiotemporal distribution of phytoplankton. Recently, phytoplankton photosynthetic pigments, fatty acids and stable isotopes have been widely used to identify and quantify phytoplankton distribution. This review highlights the use of biogeochemical markers to identify phytoplankton functional groups. It also assesses the current understanding of patterns in the spatiotemporal distribution of phytoplankton and the impact of physical and environmental factors on their distribution in estuaries and coastal oceans. The review will also gather information from in situ sampling studies to evaluate the current state of knowledge and identify gaps.

Spatio-Temporal Distribution of Phytoplankton and Water Quality of Some Rivers of Haute Sanaga Department (Central Africa)

In Cameroon, rivers are subjected to physicochemical disturbances, which increase the degradation of water quality. The aim of this study was to determine the spatio-temporal diversity of the phytoplankton groups and to evaluate the environmental parameters of the sampling sites in order to assess the quality of water in two hydrographic networks. Physicochemicals analyzes were carried out according to the standard methods while phytoplankton organisms were harvested by direct sampling and analyzed by the Utermöhl method. The analysis of Ammonia Nitrogen, Dissolved Oxygen, Electric Conductivity, Nitrates, Orthophosphates, pH, Temperature, and Turbidity.of water revealed the poor state of health of the water. Data from the Long Dry Season differed significantly (p < 0.05) from those recorded in other seasons. The phytoplankton communities were made up of Chlorophyta, Chrysophyta, Cyanophyta, and Euglenophyta with 11 classes dominated by Bacilliarophyceae (12 210 Ind/mL) and Cyanophyceae (6 208 Ind/mL). Phytoplankton densities were higher the Long Rainy Season and much lower in the Small Dry Season than in the Long Dry Season. Station near NODISCAM indicated significant organic pollution under the effect of agro-industrial discharges operating upstream of this company. For this station, the different values showed significant differences (p < 0.05) from one station to another. Finally, spatio-seasonal variations of phytoplankton densities showed logical responses to changes of physicochemical conditions in the environment. This work highlights the need to treat wastewater from collection channels before its dump into the natural environment, to prevent progressive eutrophication of the receiving aquatic environment, and poisoning by water consumption.

Spatial variation in the phytoplankton community of the Pemba Channel, Tanzania, during the south-east monsoon

The spatiotemporal distribution of phytoplankton within Tanzanian coastal waters is considered to be poorly known. Improved knowledge of the phytoplankton community, including the spatiotemporal distribution, is desirable for understanding certain aspects of trophic linkages to small pelagic fish, a key marine resource in Tanzania, and for understanding how anthropogenic activities such as terrestrial run-off and effluent discharge may impact the phytoplankton community of these waters. In this study the abundance, diversity and distribution of microphytoplankton was determined throughout the Pemba Channel during the Southeast monsoon and assessed in relation to local environmental parameters. A total of 88 species were identified during this study. Generally, diatoms dominated the microphytoplankton community of the Pemba Channel with 55 identified species (62.5% of total), followed by 31 dinoflagellate species (35.2%) and 2 cyanobacteria species (2.27%). Abundances were low, generally less than 100 cell L−1. Despite a clear dominance by diatoms within the samples, no obvious spatial pattern in their distribution was identified within the channel. Cyanobacteria meanwhile displayed a significant latitudinal gradient being more abundant in the northern half of the channel. Several harmful or potentially harmful phytoplankton species were also identified in this study including Pseudo-nitzschia sp. and Dinophysis sp., although their abundances were below the thresholds of harmful algal bloom warning systems. Nevertheless, to understand whether these species are increasing with time in response to anthropogenic activities, regular phytoplankton monitoring programs are recommended.

Evaluation of ecosystem health and potential human health hazards in the Hangzhou Bay and Qiantang Estuary region through multiple assessment approaches

Anthropogenic pollution has become a major issue governing ecosystem and human health risks. The Hangzhou Bay and Qiantang Estuary region are facing unusual perturbation due to rapid development along the embayment in recent decades. This study evaluated the organic and inorganic pollutants in water, sediment, and from the muscles of higher trophic organisms (fish, crustacean, shellfish) during four different seasons (in 2018–2019) along the Qiantang Estuary and Hangzhou Bay region to assess the ecosystem health and potential hazard status. Dissolved inorganic phosphate and nitrogen were the major pollutants in this area, which led to severe eutrophication throughout the study period. Eutrophication signals coincided well with the phytoplankton abundance, which revels the control of nutrient enrichment on the spatio-temporal distribution of phytoplankton. Food availability, along with salinity and temperature, drives the zooplankton population distribution. Heavy metals were not the issue of water quality as their concentrations meet the national and international baseline standards. However, in the sediments, Copper (Cu) and Arsenic (As) concentrations were higher than the baseline value. Towards the northwestern part of the Qiantang Estuary, the overall potential risk index of sediment with higher Cadmium (Cd) and Mercury (Hg) depicted delicate condition with moderate risk for the sediment contamination. The As concentration in fishes was close to the baseline standards limit irrespective of low As values within water and sediments. The higher concentrations of Zinc (Zn) and As in shellfish muscles, whereas other metals were within the limit of baseline standard in all the organisms. However, the hazard analysis (Targeted hazard quotient, THQ) values for the seafood consumption to human health indicates the potentially threatening consequences of shellfish and crustacean consumption on human health.

Landsat-derived environmental factors to describe habitat preferences and spatiotemporal distribution of phytoplankton

Phytoplankton species are among the most abundant and diverse organisms in marine ecosystems and are highly sensitive to physical-chemical variable changes, so they show high spatial and temporal variability related to environmental changes. This study applied Generalized Additive Models (GAM) to describe the effect of environmental factors on abundance of four phytoplankton genera recorded in a small coastal water body of northwestern Mexico. The most influential variables in order of importance were sea surface temperature, chlorophyll-a concentration, pH, salinity and dissolved oxygen. Predictions of the GAM suggested that abundance had strong spatial and seasonal variability; abundance of Tripos and Gymnodinium was higher in spring (Apr-Jun) and lower in summer (Jul-Sep); Prorocentrum was higher in autumn (Oct-Dec) and lower in winter (Jan-Mar); Pseudo-nitzschia was higher in winter and lower in autumn. The approach in this study represents one of the first efforts to use species distribution models (SDM) in phytoplankton communities using high spatial resolution environmental factors that derived from Landsat imagery. Therefore, this technique could be a useful tool with the potential to transform environmental monitoring and serve as a valuable resource in the study and application of management strategies in a wide range of activities in coastal environments, such as aquaculture, fisheries and public health.

Spatio-temporal distribution of phytoplankton in the Maralol and Salawatlol River on Salawati Island, Sorong Regency, West Papua

Maralol and Salawatlol River in southern Salawati Island, Sorong, West Papua receive tile as waste of upstream mining activities. The organic and inorganic materials in the waste could influence community structure of phytoplankton. The aim of this research was to study the relationship between plankton community and water quality. Research was conducted from 2010 to 2015 with six months sampling interval at ten sites that was separated into two temporal group. Spatial analysis was conducted to map the distribution pattern of plankton using ArcGIS 10.1 with IDW (Inverse Distance Weighted) interpolation method. There were 65 genera from six groups of phytoplankton community in Maralol River and 44 genera from five groups in Salawatlol River. There was different dominant phytoplankton group of each river at the first temporal cluster Chlorophyceae in Maralol and Cyanophyceae in Salawatlol. Furthermore, the dominant group at the second period was Cyanophyceae. The β diversity value in Maralol showed turn over condition or more variative than the Salawatlol that showed a nestedness condition. As a whole, the community of phytoplankton was highly correlated to several parameters of water quality, the TSS and dissolved inorganic nitrogen.

Spatio-temporal distribution of phytoplankton and environmental factors in the north part of Lake Gehu(Jiangsu) after muti-treatment

Lake Gehu is a representative shallow lake located in the downstream of Yangtze River in China. To identify the phytoplankton community distribution after its treatment,a survey was conducted on the phytoplanktonic community and environmental factors in its north part from January to December in 2013. According to the survey,there were altogether seven phylum,fourtythree genus and sixty-one species of phytoplankton,mainly with Scenedesmus and Cyclotella in spring and winter,Microcystis and Melosira granulata in summer and autumn. The maximum phytoplankton biomass during sampling period was 90. 6 mg / L in August,mainly with Microcystis aeruginosa. The average density of phytoplankton showed a decreasing trend from west to east,with lower vegetation coverage in the open water area. The environmental factor analysis indicated that total nitrogen,total phosphorus and water temperature were key factors that influence the phytoplanktonic density and biomass in this area. Comparing with the average biomass in the water chestnut area and reed area with that in the untreated open water area in the same month,we found that the water chestnut area decreased with the range of 72. 7%-91. 1%,and 63. 9%-83. 7% in the reed area. In August and September when algal bloom occurred in the open water area,the biomass in the chestnut area and in the reed area was only 14. 6% and30. 3% of that in the water area,respectively.

Spatio-temporal distribution of phytoplankton in four coastal rivers of southeastern of Ivory Coast (Soumié, Eholié, Ehania and Noé)

Spatio-temporal dynamics of phytoplankton and their relation to abiotic environmental factors in four rivers of south-eastern Ivory Coast (Soumié, Eholié, Ehania and Noé) was analysed from July 2003 to March 2005. The pelagic zone of each river was sampled upstream and downstream. Phytoplankton abundance was higher in Noé River (154.3 104 cells l−1) and lower in Eholié river (23.05 104 cells l−1). Dominant taxa were Microcystis aeruginosa (Kütz.) Lemmerm. and Aphanocapsa incerta (Lemmerm.) Cronberg & Komárek. In general, minimum densities of phytoplankton were observed during the rainy season, while maximum were observed in dry season in the whole stations of the rivers studied, such periods corresponding to low and high concentrations of nitrates. Among the rivers surveyed, Eholié river seems to be the least disturbed because of its higher species diversity. Seasonality fluctuations of algae abundance appear to be influenced by the flow of water and nitrate levels. This work is a useful starting point for future research on micro algae in Ivory Coast. Nous avons analysé la dynamique spatio-temporelle du phytoplancton et sa relation avec des facteurs environnementaux abiotiques dans quatre cours d'eau du sud-est de la Côte d'Ivoire (Soumié, Eholié, Ehania et Noé) de juillet 2003 à mars 2005. Des échantillons furent prélevés dans la zone pélagique de chaque cours d'eau, en amont et en aval. Le phytoplancton était plus abondant dans la Noé [(154,3 104 cellules l−1) et moins dans l'Eholié (23,05 104 cellules l−1). les taxons dominants étaient Microcystis aeruginosa (Kütz.) Lemmerm, et Aphanocapsa incerta (Lemmerm.] Cronberg & Komárek. En général, nous avons observé les densités minimales de phytoplancton pendant la saison des pluies et les densités maximales pendant la saison sèche dans toutes les stations des cours d'eau étudiés, ces périodes correspondant respectivement à des concentrations faibles et élevées de nitrates. De toutes les rivières étudiées, l'Eholié semble être la moins perturbée vu sa plus grande diversité d'espèces. Les fluctuations saisonnières de l'abondance d'algues semblent être influencées par le débit de l'eau et les taux de nitrates. Ce travail est un point de départ utile pour toute recherche future sur les micro-algues de Côte d'Ivoire.

Spatio-temporal distribution of phytoplankton in the Danjiangkou Reservoir, a water source area for the Southto-North Water Diversion Project (Middle Route), China

One of the water source areas of the South-to-North Water Diversion Project is the Danjiangkou Reservoir (DJKR). To understand seasonal variation in phytoplankton composition, abundance and distribution in the DJKR area before water diversion, as well as to estimate potential risks of water quality after water diversion, we conducted an investigation on phytoplankton in the DJKR from August 2008 to May 2009. The investigation included 10 sampling sites, each with four depths of 0.5, 5, 10, and 20 m. In this study, 117 taxa belonging to 76 genera were identified, consisting of diatoms (39 taxa), green algae (47 taxa), blue-green algae (19 taxa), and others (12 taxa). Annual average phytoplankton abundance was 2.01 × 106 ind./L, and the highest value was 14.72 × 106 ind/L (at site 3 in August 2008). Phytoplankton abundance in front of the Danjiangkou Dam (DJKD) was higher than that of the Danjiang Reservoir Basin. Phytoplankton distribution showed a vertical declining trend from 0.5 m to 20 m at most sites in August 2008 (especially at sites of 1, 2, 4 and 10), but no distinct pattern in other sampling months. In December 2008 and March 2009, Stephanodiscus sp. was the most abundant species, amounting to 55.23% and 72.34%, respectively. We propose that high abundance of Stephanodiscus sp. may have contributed greatly to the frequent occurrence of Stephanodiscus sp. blooms in middle-low reaches of the Hanjiang River during the early spring of 2009. In comparison with previous studies conducted from 1992 to 2006, annual average phytoplankton density, green algae and blue-green algae species, as well as major nutrient concentrations increased, while phytoplankton diversity indices declined. This indicates a gradual decline in water quality. More research should be conducted and countermeasures taken to prevent further deterioration of water quality in the DJKR.

A recently landlocked brackish-water lagoon of Lake Tanganyika: physical and chemical characteristics, and spatio-temporal distribution of phytoplankton

Monthly measurements of physical and chemical characteristics were made at two localities in the eastern part of a recently landlocked lagoon of Lake Tanganyika. Variables analysed were: temperature, pH, conductivity, sodium, potassium, magnesium, calcium, carbonate, bicarbonate, chloride and sulphate. Large seasonal fluctuations of salinity were recorded (1.68–8.21 g l−1). The seasonal water input controlled algal seasonality mainly through its effect on salinity and indirectly through its influence on nutrient concentration by dissolution and dilution of the excrements of the numerous cattle and other organic matter. Phytoplankton was mainly composed of Cyanophyta and Euglenophyta. Euglenophyta dominated during the dry periods with high salinity and probably very high nutrient levels, while Cyanophyta preferred moderate salt and nutrient concentrations during the rainy periods. The phytoplanktonic community was composed of a large number of perennial and a reduced quantity of annual organisms.