Green HealthGreen TalkPollution
February 21, 2021 — 04:43pm GMT+0000

Why toxic algae blooms like Florida’s are so dangerous to people and wildlife

Pramodya Editor

Algal blooms including toxic events can be a result of a natural phenomenon or else that can be a result of man-made pollution (Anderson, D.M., Glibert, P.M. and Burkholder, J.M., 2002). The term algal blooms refer, rapid growth of microscopic algae or cyanobacteria in water often resulting in a colour scrum on the water surface. Even though algal blooms can also happen due to natural environmental activities, it also taken place due to industrial runoff. In recent decades algal growth in waterways has been rising exponentially due to the influx of wastewater containing high amounts of nutrients. Industrialized countries like America, Europe and Eastern Asia have become hotbeds for these incidents due to runoff of industrial waste and because of the high consumption of manufactured fertilizers. The events become highly noticeable when the colour and odor of natural water change with a visible fish kill.

A highly visible new case lately developed in Florida, was an intense algal growth in the largest freshwater lake of the state. The algal bloom of this lake Okeechobee, grabbed the attention because of the large size of the algal bloom, which covered 33 square miles of the water surface. This matter was taken into consideration seriously by the authorized people, because that triggered damages to the economy of the state, harming local tourism, fishing, and boating businesses. Also due to this, Floridians bothered about the environmental degradation that occurred as a result of this incident.

Blue-green algae, Diatoms, and Dinoflagellates are the three types of single-celled algae that cause algal blooms. Among those three, Blue green algae frequently cause harmful blooms in coastal waters. The other two tend to bloom at more seaward locations. It is still in debate about the cocktail of nutrients responsible for blooms; whether it is nitrate, ammonia, orthophosphates or it is, organic nutrients such as urea. Anyway, it has clearly been understood that land use has a strong bearing on types of nutrients that are delivered downstream to bloom-prone water bodies.

Manufactured fertilizers for agricultural crops, animal feed and rain borne emissions from burnt fuel can add mass nutrients to water sources. The effects of algal blooms are direct and indirect. Most prominent indirect effect is hypoxia, which refers to the low level of oxygen in the water source. This hypoxia situation can reach into anoxia level at an instance, causing severe damage to the aquatic life creating mass fish and other aquatic deaths. Toxicity is the most direct effect of algal blooms. Blooms of algal types such as red tide organism, a dinoflagellate (Karenia brevis) creates a toxin called brevitoxin that can create high fish kills.

It has been found that water stagnation enhances blooms by giving the algae enough time to remain calm in surface waters, where the sunlight needed for photosynthesis is most abundant. In Florida, as the water is withdrawn from the water sources, for various activities, the stagnation process enhances creating rapid algal blooms. As the possible remedies for the above economic, health and ecosystem impacts, Floridian managers have set pollution limits to waterways to lessen the nutrient runoff that fuels algal blooms. Detailed computer models of water circulation should be used more routinely in the course of water management to predict the locations where the algal blooms would occur in the future.