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A case study of ocean acidification and South Florida’s coral reefs.
Title
A case study of ocean acidification and South Florida’s coral reefs.
Name/Creator
Camden, Lauren
Abstract/Description
Levels of the greenhouse gas carbon dioxide have been increasing dramatically in the atmosphere since the onset of the Industrial Revolution with a sharp escalation occurring due to anthropogenic causes such as the burning of fossil fuels. The ocean acts as a carbon sink for this atmospheric CO2, absorbing a large majority of it. This process causes a chemical reaction that has been increasing the acidity level of ocean water and progressively lowering the average pH value. When a carbon...
Show moreLevels of the greenhouse gas carbon dioxide have been increasing dramatically in the atmosphere since the onset of the Industrial Revolution with a sharp escalation occurring due to anthropogenic causes such as the burning of fossil fuels. The ocean acts as a carbon sink for this atmospheric CO2, absorbing a large majority of it. This process causes a chemical reaction that has been increasing the acidity level of ocean water and progressively lowering the average pH value. When a carbon dioxide molecule is absorbed into sea water, two positively charged ions are produced. Because pH value is a measurement of hydrogen ion concentration in any given solution, these added hydrogen ions effectively lower the pH value of the ocean. Since these hydrogen ions are positively charged, they go on to interact with the negatively charged bases already present in the ocean. One of these bases is CaCO3, or the carbonate ion. Carbonate is essential to calcifying marine organisms, who use this ion to build and maintain their shells and skeletons. However, as atmospheric carbon dioxide levels increase and the resulting chemical reactions occur, the ocean’s carbonate saturation decreases. Coral is one such calcifying organism that essential to the aquatic ecosystem in a number of ways, most of which can be attributed to the fact that coral reefs are one of the planet’s most biodiverse ecosystems despite inhabiting only a very small portion of the ocean. Several studies have linked coral’s carbonate production to their ability to create functional skeletons. One such study was published by Kuffner et al in 2013 in the Florida Keys. Four sites ranging from Miami to the Dry Tortugas were selected, and two batches of forty Siderastrea siderea (massive starlet coral) each were selected for two experimental runs. At six-month intervals, these samples were analyzed to determine linear expansion rates and calcification levels. After analysis in both runs, a strong correlation between linear expansion rates and calcification levels was determined. Corals that experienced heightened calcification rates also experienced heightened linear expansion. This experiment solidified the negative affect ocean acidification will have in future years on coral reefs if left unacknowledged. Langdon et al also published an experiment done in the Florida Keys in 2013 that determined a relationship between increased atmospheric CO2 levels and decreased calcification rates of coral. Eleven samples of a combination of Siderastrea radians (shallow water starlet coral) and Solenastrea hyades (smooth star coral) were epoxied to cinderblocks with sensors recording environmental data at thirty-minute intervals. Random samples were incubated in tanks in situ and given a treatment regime designed to simulate increased ocean acidification conditions through chemical injections of NaHCO3 (sodium bicarbonate) and HCl (hydrogen chloride). This treatment lowered pH value in the incubation chambers by 0.1 to 0.2 units. Calcification rates of the incubated coral samples were determined through statistical analysis. Coral samples that experienced a 0.1 unit drop in pH value experienced decreased calcification rates of 50% and coral samples that experiences a 0.2 unit drop in pH value experienced a decreased calcification rate of 52%. Both of these studies combined showcases the two-part threat ocean acidification is placing on coral reefs in the Florida Keys. As the average pH of ocean water drops, corals are unable to achieve net carbonate accretion and calcification rates drop. This causes corals to experience stunted linear expansion, density, rugosity, and reproduction rates. As coral population dwindles, Florida will experience several negative socio-economic impacts such as diminished coastal protection from storms, tourism, income and jobs created by fisheries, and medicinal opportunities as new life-saving medicines will no longer be able to be harvested from dying reefs. Mitigation and adaptation methods must include reducing other local stressors to coral.
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Date Issued
2020-06-15
Identifier
BC744
Format
Document (PDF)
PURL
http://purl.flvc.org/broward/fd/BC744
A literature review of ocean acidification’s effect on coral calcification rates and skeletal growth.
Title
A literature review of ocean acidification’s effect on coral calcification rates and skeletal growth.
Name/Creator
Camden, Lauren
Abstract/Description
Ocean acidification is one of many threats to marine life as a result of increasing levels of atmospheric carbon dioxide being absorbed by ocean water. Anthropogenic levels of carbon dioxide have been rising dramatically in the atmosphere since the onset of the Industrial Revolution, with a sharp escalation occurring due to practices such as the burning of fossil fuels. The ocean acts as a carbon sink for atmospheric CO2, absorbing a large portion of it. This process causes a chemical...
Show moreOcean acidification is one of many threats to marine life as a result of increasing levels of atmospheric carbon dioxide being absorbed by ocean water. Anthropogenic levels of carbon dioxide have been rising dramatically in the atmosphere since the onset of the Industrial Revolution, with a sharp escalation occurring due to practices such as the burning of fossil fuels. The ocean acts as a carbon sink for atmospheric CO2, absorbing a large portion of it. This process causes a chemical reaction that progressively lowers the average pH of oceans globally. When a carbon dioxide molecule is absorbed into sea water, two positively charged ions are produced. As pH value is a measurement of hydrogen ion concentration in any given solution, these added hydrogen ions effectively lower the pH of the ocean and causes it to be more acidic. Since these hydrogen ions are positively charged, they to interact with the negatively charged bases already present in the ocean. One of these bases is CaCO3, or the carbonate ion. Carbonate is essential to calcifying marine organisms, who use this ion to build and maintain their shells and skeletons. However, as atmospheric carbon dioxide levels increase and the resulting chemical reactions occur, the ocean’s carbonate saturation decreases. Coral is one such calcifying organism that essential to the aquatic ecosystem in a number of ways, most of which can be attributed to the fact that coral reefs are one of the planet’s most biodiverse ecosystems despite inhabiting only a very small portion of the ocean. With this process occurring at accumulative speeds, how will ocean acidification affect the calcification rates- and therefore the growth and development- of coral in the coming years worldwide? Several studies have confirmed the relationship between increased carbon dioxide levels and the resulting decreased calcification levels and structural deformities present in coral reefs. In 2005 Langdon et al published a study that tested coral calcification rates with varying rates of carbon dioxide saturation in ocean water. Specimens of Porites compressa (finger coral) and Montipora verucosa (rice coral) were collected off the coast of Hawaii and placed in an offshore experimental flume where a series of incubations were performed in Summer 1999 and Winter 2000. From August to September 1999, eighteen incubations were performed with ambient conditions and nine incubations were performed with pCO2 levels at 1.7 times what ambient conditions were. A second round of fifteen incubations were performed from January to February 2000. Six incubations were done at an ambient pCO2, two were done at 1.4 times, and six were done at 2.0 times ambient conditions. Calcification rates for all incubations were calculated through statistical analysis. As a result, calcification decreased 26%, 40%, and 80% respectively to increased pCO2. Another such study was conducted by Langdon et al again in 2013, this time in the Florida Bay. Samples of Siderastrea radians (shallow starlet coral) and Solenastrea hyades (smooth star coral) were collected near Peterson Key and attached to cinderblocks with sensors logging environmental data such as pH and temperature at thirty-minute intervals. A random subset of these corals was incubated in situ and given a treatment regime designed to simulate increased ocean acidification conditions. This treatment lowered pH value in the incubation chambers by 0.1 to 0.2 units. Calcification rates of the incubated coral samples were determined through statistical analysis. Coral samples that experienced a 0.1 unit drop in pH value experienced decreased calcification rates of 50% and coral samples that experiences a 0.2 unit drop in pH value experienced a decreased calcification rate of 52%. These studies both exemplified the strong correlation that exists between pCO2 present, increased acidity in ocean water, and decreased calcification rates of coral. In 2016, Foster et al published a study that demonstrated the structural deformities coral experience as a result of this calcification reduct.
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Date Issued
2020-06-15
Identifier
BC742
Format
Document (PDF)
PURL
http://purl.flvc.org/broward/fd/BC742
Establishing a Long term Monitoring Plan for Hallandale Beach, Florida Nearshore Coral Reef Habitats.
Title
Establishing a Long term Monitoring Plan for Hallandale Beach, Florida Nearshore Coral Reef Habitats.
Name/Creator
Pollard, Madison Jane
Abstract/Description
The city of Hallandale Beach, Florida adopted the “Our Local Coral Reef Protection Ordinance” in June of 2019, with plans to restore their coastline and protect the community from future storm surges. Ordinance No. 2019 1- 011 added sections 5 to 8 in Chapter 13 "Health and Sanitation" of the city of Hallandale Beach code of ordinances, which outline strategies to protect and restore the resilience of the nearshore coral reef. Complex coral reef systems bring higher biodiversity and will...
Show moreThe city of Hallandale Beach, Florida adopted the “Our Local Coral Reef Protection Ordinance” in June of 2019, with plans to restore their coastline and protect the community from future storm surges. Ordinance No. 2019 1- 011 added sections 5 to 8 in Chapter 13 "Health and Sanitation" of the city of Hallandale Beach code of ordinances, which outline strategies to protect and restore the resilience of the nearshore coral reef. Complex coral reef systems bring higher biodiversity and will raise the economic value of the reef to tourism. The length of Hallandale Beach shoreline is approximately 0.80mi (4200ft). Acropora cervicornis (Staghorn coral), a critically endanger species, is said to be found ½ mile off the coast of Hallandale Beach and is an important reef-building species to be monitored. This proposal will establish a long-term monitoring plan and baseline for the nearshore coral reef based on the Atlantic and Gulf Rapid Reef Assessment (AGRRA) protocols. It will briefly outline procedures needed to accomplish the three different monitoring surveys and important indicators each SCUBA diver will be required to record. Corals are the primary builders of reef habitats and they benefit from the presence of reef fish and benthic organisms. Reef fish have different eating habits that promote positive structure changes such as, keeping turf algae in check clearing room for recruitment of polyps. Benthic promotors such as, crustose coralline algae and minimal turf algae encourage a healthy reef habitat. According to a map of Broward County, Florida reef structure created by Brain Walker, the linear reef inner begins about 0.80 mi (4200ft) and the liner reef middle ends at about 1.75mi (9240ft) from the shore. There appears to be no linear outer reef off the coast of Hallandale Beach. There is no previous baseline to compare future surveyed data or confirm presence and density of diver sighted Acropora cervicornis. Baselines are important historical data that enables the city to identify changes in the complexity of the reef structure and responses to climate change to make proactive decisions. An initial baseline of Hallandale’s reef will be made to be comparable with future monitoring data, as well as determine the effectiveness of the management plans in place. AGGRA protocols require a minimum of six divers and with the use of city vendors, equipment costs can be as low as 230 dollars. Without a coral reef, the city may face costly damages from natural disasters such as hurricanes. Coral Reefs provide protection against storm surges that without, coastal erosion would increase and leave the city without an offshore defense against high energy wave action. AGRRA protocols will be applied to create a basic level survey easily adaptable, this will provide community building and outreach opportunities through citizen science and volunteering.
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Date Issued
2020-06-15
Identifier
BC746
Format
Document (PDF)
PURL
http://purl.flvc.org/broward/fd/BC746
Monitoring coral bleaching and disease through the Southeast Florida Action Network BleachWatch program.
Title
Monitoring coral bleaching and disease through the Southeast Florida Action Network BleachWatch program.
Name/Creator
Camden, Lauren
Abstract/Description
Corals are made up of many animals called coral polyps, which receive ninety percent of their food and energy through photosynthesis from microscopic algae living within them called zooxanthellae. These algae have a symbiotic relationship with coral, both relying on each other to survive. The zooxanthellae give corals their characteristic colorful appearance. However, when placed under stress coral expel their zooxanthellae, exposing their white tissue and skeletons, and losing their main...
Show moreCorals are made up of many animals called coral polyps, which receive ninety percent of their food and energy through photosynthesis from microscopic algae living within them called zooxanthellae. These algae have a symbiotic relationship with coral, both relying on each other to survive. The zooxanthellae give corals their characteristic colorful appearance. However, when placed under stress coral expel their zooxanthellae, exposing their white tissue and skeletons, and losing their main food source. This is called coral bleaching and has been occurring in increasing severity in the last twenty years. Mass bleaching events have been increasingly observed where a wide range of species bleach over a large area of reef. These mass bleaching events have been correlated to rising sea surface temperatures that cause the coral thermal stress. A rise in temperature of only one to two degrees Celsius can trigger bleaching events, and when long term averages are raised, mass bleaching is more likely to occur. This can cause eventual mortality if environmental stressors are not resolved quickly enough to give corals a chance to recover. Disease is the second part of the two-part threat causing coral casualties in the tropical Atlantic and wider Caribbean region. Beginning in the 1970s, disease has been observed at staggering levels worldwide and is the result of a bacteria, virus, fungus, or abnormal growth. In the Florida Reef Tract, this can present as black band disease, stony soral tissue loss disease, or tumors. It is identified by a change in tissue color or structure and causes tissue loss and eventual mortality. BleachWatch is a program designed to detect and monitor coral bleaching events and disease outbreaks in the Florida Reef Tract and serve as an early warning system for bleaching events. Southeast Florida Action Network (SEAFAN) in conjunction with the Florida Department of Environmental Protection developed the SEAFAN BleachWatch program in 2013 as a compliment to the Florida Keys BleachWatch program managed by Mote Marine Laboratory and the Florida Keys National Marine Sanctuary. The northernmost one-third of the Florida Reef Tract is in the SEAFAN BleachWatch program’s jurisdiction, beginning at the end of Biscayne National Park, and ending at the Hobe Sound National Wildlife Refuge. BleachWatch consists of a combination of oceanographic data and field observations recorded by an Observer Network made up of trained volunteers and scientists that are used to generate a Current Conditions Report monthly, weekly, or bi-weekly, depending on conditions. The National Oceanic and Atmospheric Administration’s Coral Reef Watch is used to predict likelihood of future bleaching events and alerts are sent out to the Observer Network if a risk of bleaching is deemed. Participants then complete and submit data sheets to be used in the next Current Conditions Report. In 2019, three such reports were generated in July, September, and October. Sea surface temperatures remained consistently above monthly averages in two-thirds of the reports, and bleaching and disease were consistently reported, especially in Broward County. However, participation was low, with only nineteen data sheets being submitted over the entire annual period. More participation and submitted data sheets are greatly needed for more accurate results and better analysis. Still, the program has helped to improve scientific understanding regarding the timing, distribution, and severity of disease and bleaching in southeast Florida. It also gives citizen scientists the chance to be involved in collecting data to enable the restoration of their local reefs and enables assessment of the health of the Florida Reef Tract while providing an outlook for potential future events. Current Condition Reports aid in making responsible management decisions by the Florida Department of Environmental Protection and the Florida Keys National Marine Sanctuary regarding Florida’s beautiful and invaluable coral reef ecosystems.
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Date Issued
2020-06-15
Identifier
BC743
Format
Document (PDF)
PURL
http://purl.flvc.org/broward/fd/BC743