Harmful algal bloom

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Cyanobacteria is a form of blue-green algae that produces toxins that can be harmful to both human and marine health. [1] These blooms are commonly referred to as harmful algal blooms (HABs). They can develop in aquatic environments, both fresh water and salt water which can be accumulated through fish that feed on the algae like sardines, anchovies, and other microorganisms. Consequently, birds and other animals that feed on them are poisoned as well. [2] HABs can be especially threatening to drinking water and marine life even with the slightest toxin level.

The growth of cyanobacteria in fresh water, Photo courtesy of Dr. Jennifer L. Graham, U.S. Geological Society "[Harmful algal blooms]".

Effects of climate change on HABs

Harmful blooms are predicted to occur more often due to a combination of factors including: global warming, ocean acidification, and land-use changes. [3] With the rise of ocean temperatures, warmer water will be able to generate better circumstances for HABS to grow; meaning blooms can potentially cause more relentless toxic outbreaks. [4] Additionally, more severe blooms will be a result of heavy rainfall producing discharge and nutrients from rivers surrounding Lake Erie. Ultimately, feeding to the growth of algae blooms. Large amounts of nutrients from fertilizers and sewage are flowing into lakes and streams threatening aquatic ecosystems. [1] Agencies such as NOAA, NASA, EPA, and the U.S. Geological Survey are all taking action to research an early warning system for toxic algal blooms in fresh water using satellites. These satellites scan Earth’s freshwater forms to gather color data, which show the spread of HABs. This project will further help scientist to understand the environmental causes and health effects of cyanobacteria blooms. [1]

Effects on aquatic ecosystems

HABs have been known to poison a number of fresh water lakes and marine life including fish and shellfish. Several U.S. coastal states have suffered a number of harmful algal blooms attacks over the last decade. As a result, species have appeared in new locations that were not previously known to have problems with HABs. [5] However, when these blooms emerge, shellfish fisheries are monitored for toxins and are closed when necessary to protect human health. Although HABs are toxic and dangerous for both human and marine life, nontoxic blooms can be just as threatening by suffocating fish, blocking light from bottom-dwelling plants, and depleting the oxygen in the water. Low oxygen can occur naturally, but it is often caused by poor water quality from human activities including excessive nitrogen or phosphorus, pollution, sewage, and urban runoff. [5]

Lake Erie

Lake Erie is one of the most discussed lakes that has been in high risk of HABs. [1] NOAA has predicted that the 2015, Western Lake Erie HABs season will be the most severe. HABs in Lake Erie are expected to measure 8.7 on the severity index, ranging from 8.1 to 9.5 as the potential high. The effects of these blooms initiate higher costs for cities and government to treat drinking water and ensure swimmer safety in areas highly concentrated. With the use of satellite color data, HABs will be forecasted for potential threats of dangers in surrounding areas of Lake Erie. [1]

NASA satellites capture HABs currents in lake Erie "[HABs in Lake Erie]".

Shellfish fisheries

HABs are growing across the West Coast, specifically in California. For this reason, a number of fisheries have been closed in Washington, Oregon, and California due to high levels of domoic acid in filter feeders like mussels and clams. Toxicity levels in shellfish range from 95 parts per million to 400 parts per million, while the legal limit for safe human intake is 20 parts per million. These toxins are found in filter feeders digestive tracts, which can ultimately be fatal. [4] As a result, Northwest Fisheries Science Center (NWFSC) has been monitoring toxin levels and enforcing closures to ensure commercial seafood remains safe to eat. [2] Another concern of HABs in fisheries is Hypoxia, a deficiency in the amount of oxygen reaching the tissues. It is closely related to HABs because these toxins can cause reduced oxygen in aquatic ecosystems. In the Gulf of Mexico, large oxygen-depleted areas also known as “dead zones” are endangering fisheries and threatening water supply. [5] HABs are a national concern and understanding and predicting algal blooms is the biggest challenge. NOAA has received a $2.1 million grant that will contribute to organizations around the country addressing HABs and hypoxia. The project will consist of developing a network of ecological forecasts, so that communities are protected and more resilient to the threats of HABs. Additionally, NOAA is currently developing a robotic system to better detect algal blooms that pose a threat to water ecosystems. [5]

Overcoming environmental threats

Wayne State University in Detroit, Michigan recently discovered that HABs can be converted into material for Na-ion batteries after collecting samples from Lake Erie. [6] These findings can be promising for the future of HABs to overcome environmental threats. Based on the findings at the University, HABs can provide reversible sodium storage in Na-ion batteries. Amazingly, HABs can also be converted into hard carbon with heat and there is no need for purification or additional processes. More importantly, researchers discovered that the overall electrode maintained a good capacity for retention. Although this is only a possible solution for HABs, other environmental organizations such as NOAA Fisheries, USGS, EPA, NASA and many more are still conducting research on how to effectively prevent potential threats of toxic blooms. [6]

See also

Other closely related articles in this wiki include:


  1. 1.0 1.1 1.2 1.3 1.4 NOAA. (2015, July 9). NOAA, partners predict severe harmful algal bloom for Lake Erie. Retrieved September 24, 2015 [1]
  2. 2.0 2.1 Milstein, M. (2015, June). NOAA Fisheries mobilizes to gauge unprecedented West Coast toxic algal bloom - Northwest Fisheries Science Center. Retrieved September 24, 2015 [2]
  3. Kerlin, K. (2015, June 4). What killed California’s sea stars and urchins? - Futurity. Retrieved October 10, 2015 [3]
  4. 4.0 4.1 Hill, T. (2015, June 19). The West Coast’s Massive Algal Bloom Could Be the Toxic Wave of the Future | TakePart. Retrieved October 9, 2015 [4]
  5. 5.0 5.1 5.2 5.3 NOAA. (2015, September 17). NOAA awards $2.1 million to improve observation, forecasting, and mitigation of harmful algal blooms and hypoxia. Retrieved October 2, 2015 [5]
  6. 6.0 6.1 Tecson, K. (2015, October 12). Harmful algae may be used to boost high-performance batteries, scientists reveal. Retrieved October 10, 2015 [6]

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