Effect of Physico-chemical Parameters on the Population Diversity of Potentially Harmful Micro-algae during Post-monsoon Season along the Malabar Coast

Abstract

There are several toxic microalgae species known as Harmful algal bloom (HAB) causing serious effects to the environment and economy. Knowledge on these groups of marine micro-flora is scanty and several areas remain unexplored. The present study focuses on the analysis of microalgal diversity in the Malabar coastal areas at Southwest and Northeast monsoon. The diatoms, dinoflagellates and total microalgal population were analysed and quantified. Predominant species were identified. Physicochemical parameters of the seawater at different time intervals and Correlation between diatoms, dinoflagellates and total microalgae population with physicochemical parameters were identified. From the analysis, a total of 53 diatoms and 15 dinoflagellates were identified. The predominant species including toxic or harmful bloom-forming were found to be Dinophysis caudata, Noctiluca scintillans, Prorocentrum lima and Tripos furca. The total microalgae population varied from 18,592 cells/L to 7,832 cells/L in the months of April and December. Dinoflagellates were positively correlated with salinity (r = 0.848; p = 0.008), nitrite (r = 0.752; p = 0.032) and total phosphorous (r = 0.734, p = 0.038). Diatoms were positively correlated with temperature (r = 0.804; p = 0.016) and nitrate (r = 0.774, p = 0.024). Total microalgal density was positively correlated with temperature (r = 0.825; p = 0.012) and nitrate content (r = 0.811, p = 0.15).

Using FlowCam and molecular techniques to assess the diversity of Cyanobacteria species in water used for food production

“…Calculations of mean and standard deviation were also carried out using the Microsoft (MS) Excel 2010 spreadsheet for each sampling point. Pearson’s correlation coefficient analysis was used to measure aspects of the linear relationship between various physicochemical parameters observed in all water samples 49 , 50 .…”

Water physicochemical characterization and phytoplankton diversity of arid region in Meggarine Lake, Ouargla, Algeria

“…Furthermore, phytoplankton abundance increased when nutrient concentrations rose, and vice versa (Litchman et al 2015). In the study carried out by Sankaranarayanan et al (2021), it was determined that the relation between total microalgal density and physicochemical properties was positively correlated with temperature (r = 0.825; p = 0.012), salinity (r = 0.848; p = 0.008), Diatoms (r = 0.804; p = 0.016), and Dinoflagellates (r = 0.848; p = 0.008). Dinoflagellates positively connected with total phosphorus and nitrite (r = 0.734, p = 0.038, and 0.752, respectively).…”

“…Microalgae are thought to be responsible for approximately 2x10 9 tons of the total yearly primary generation of carbon in the world's oceans. In addition, the creation of 80% of the oxygen we breathe is also carried out by them (Verfaillie et al 2020;Sankaranarayanan et al 2021). Changes in their physicochemical properties significantly impact the organisms that inhabit ecosystems.…”

Impacts of Agricultural Practices (Pesticides and Fertilizers) and Amalnala Stream on Amalnala Lake in Gadchandur, India

“…8 C y a n o b a c t e r i a c a n u t i l i ze t h e organophosphates present in the water bodies as nutrient and grow luxuriantly. 9 Certain cyanobacteria are known to favour the growth in alkaline environments and may produce uniform growths called as blooms. Anthropogenic activities and the mining activities (open cast and underground) are responsible for altering the ecology of nearby waterbodies.…”