Algae bloom

1. Algae bloom

2. What is algae bloom ? In either freshwater or saltwater, it is the fast development and accumulation of phytoplankton, a tiny and basic free-floating water plant. Because of the colour the bloom provides the sea, algae blooms are also referred to as red tides. The flowers, however, are neither tidal nor entirely red.

3. What are harmful algae bloom ? When toxin-producing algae overgrow in a body of water, a hazardous algal bloom (HAB) arises. Algae are tiny creatures that live in water and, like plants, use photosynthesis to generate energy from sunlight. Depending on the kind of algae, the excessive algal growth, or algal bloom, becomes apparent to the human eye and can be green, blue-green, red, or brown.

4. Why do harmful algae bloom (HAB) occur? Warmer water temperatures in the summer, combined with extra nutrients from fertilisers or sewage waste carried by runoff, result in harmful algal blooms. According to experts, there might be a slew of additional causes for HABs, many of which are connected to climate change.

5. Impact of HAB on humans? Direct exposure to toxic algae can be harmful and can cause serious health problems such as - • Rashes • Stomach or liver illness • Vomiting • Respiratory problems • Neurological effects • Diarrhea • Short term memory loss

6. Impact of algal bloom on economy • Nitrates and algal blooms in drinking water drive up treatment costs dramatically. Cleaning up contaminated water bodies costs billions of dollars every year. • Every year, the tourism industry loses close to a dollar due to fishing and boating. • The fishing and boating sectors have suffered significant losses. • Clean water may increase the value of neighbouring properties by up to 25%.

7. Ways to control/prevent HABs There are several ways to control HABs- • Physical control • Chemical control • Biological control • Direct nutrient removal

8. Physical control Physical methods include - • Aeration • Mechanical mixing • Surface skimming • Ultrasound

9. Aeration Aeration is the process of pumping air into water bodies from an aeration device at the bottom of the water bodies. This causes plumes of air to develop, disrupting water body stratification and limiting nutrition availability.

10. Mechanical mixing Mixers are positioned on the surface of water bodies, and water is pushed downwards from the surface to remove the water. This procedure mixes the water, causing stratification to be disrupted and reducing the nutrients available to the algae.

11. Surface skimming Algae blooms frequently produce surface scums. Oil skimmers can be used to remove algae. .

12. Ultrasound To destroy the algae, ultrasonic vibrations of a certain frequency are utilised.

13. Chemical controls In chemical controls we include various methods - • Algaecides • Barley straw • Coagulation

14. Algaecides Algaecides are the compounds that kill algae and they generally include- • Copper sulphate • Potassiumpermanganate • Chlorine • lead

15. Barley straw Bales of barley straw that are placed in the water and when they are exposed to sunlight and oxygen , the straw produces a chemical that stops algae growth. The only problem with this method is that they cannot react chemically without the absence of sunlight.

16. Coagulation Coagulation is the process when chemicals are introduced into the water that makes the algae coagulated mand fall to the bottom of the pond or lake. At the bottom since there is no sunlight , oxygen or other critical resources eventually it dies.

17. Biological controls Biological controls include removal of algae from water which uses followingmethods- • Floatingartificial wetlands • Increasing grazingpressure

18. Floating artificial wetlands Floating treatment wetlands (FTWs), sometimes known as islands, are tiny man made platforms that allow aquatic emergent plants to thrive in water that is normally too deep for them. Their roots extend across the floating islands and into the sea, forming thick root columns with a large surface area.

19. Increasing grazing pressure

20. Direct nutrient removal We add alum and phoslock to the water in this approach, which reduces algal bloom control. However, the Thai method has the drawback of being ineffective and inefficient.