Question

Diatoms grow very quickly, but require silica (a silicon-based nutrient which is abundant in river water and in neritic waters). Dinoflagellates typically grow much more slowly, but they do not require silica. Your initial sampling indicates that the population is nearly 50/50. What changes (if any) would you expect if the initial phytoplankton community were transported closer to the mouth of Biloxi Bay? What changes (if any) would you expect if the population were transported further offshore? Explain your answers…

Consider your answer to Question above, particularly the population of diatoms and dinoflagellates which were transported near the shore. Consider also that holoplankton and meroplankton are typically very abundant in nearshore waters... If the dinoflagellates in that phytoplankton community happened to be a foul-tasting, toxic species (like K. brevis), how do you think the holo/meroplankton would respond? Hypothesize how grazing could cause a Red Tide near the coast. Now hypothesize how grazing could prevent/eliminate a Red Tide near the coast. Be explicit in your hypotheses...

Answer 1

QUESTION 1- What changes would you expect if the initial phytoplankton community were transported closer to the mouth of Biloxi Bay ?

ANSWER -  The phytoplanktons grow abundantly closer to the shore and these will harmful to other organisms on that area. They consume nutrients from the shore and further effects the organisms health thereby reduces economy . With the available nutrients, they will grow . Especially , diatoms grow faster than dianoflagellates because coastal water contains more silica .

QUESTION 2 - What changes would you expect if the population were transported further offshore ?

ANSWER - If they transported to the offshore both of them will grow. Dianoflagellates grow slower than diatoms in normal conditions . Here , the growth of diatoms depends on silica availability of the offshore water. The diatoms growth may retards without the availability of silica.

QUESTION 3 - How do you think the holo/meroplankton would respond?

ANSWER - Dianoflagellates produce chemicals and acts as neurotoxins to holo/meroplankton . These toxins are harmful to them and also effect their growth . Red tide is harmful for these planktons and even causing death of them .

QUESTION 4 - Hypothesize how grazing could cause a Red Tide near the coast .

ANSWER - Red tide is harmful to both animals and plants. Grazing of Karenia brevis by other phytoplanktons cause harmful to them.

If grazing is strong ,to sustain K.brevis life they will move towards the coast.

QUESTION 5 - Hypothesize how grazing could prevent/eliminate a Red Tide near the coast .

ANSWER - The harmful Ride Tide near the coast can be eliminate by bio-control ,potential grazers by providing an food for grazer species. There by , Red Tide can be eliminate.