Coral Bleaching and Coral Core Data Analysis

Eleven samples of a coral species (Acropora hyacinthus) were placed to a moderately variable heat pool (MV, in blue) or a highly variable heat pool (HV, in red). After the corals spent a period of time in their new environments, they were exposed to heat stress. The amount of chlorophyll that remains in the corals after heat stress was then measured. Which of the following conclusions would be supported by the data (CHECK ALL THAT APPLY)

• Moderately Variable Heated corals were more resistant to bleaching

• Highly Variable Heated corals were more resistant to bleaching

• Zooxanthellae in moderately variable corals denatured more under heat stress

• Zooxanthellae in moderately variable corals denatured less under heat stress

Which number would represent photosynthetic activity when zooxanthallae enzymes have been denatured?

• 1

• 2

• 3

Researchers measured the amount of zooxanthellae symbiont present inside the body of corals. Which of the following accurately describes the results of the study?

• Symbiosis starts to fail at elevated temperatures

• Symbiosis remains stable at elevated temperatures

• Symbiosis is unaffected by temperature

Researchers measured the photosynthetic yield (how much energy in produced) by zooxanthellae at different temperatures. Which of the following accurately describes the effects of corals being exposed to elevated temperatures for extended periods?

• Coral are able to obtain more energy from the zooxanthellae because they are receiving more sunlight

• Coral are able to obtain more energy from the zooxanthellae because photosynthetic yield increases over time.

• Coral are able to obtain less energy because the symbionts have been expelled

When interpreting coral cores, ​ (a)   density bands indicate​ ​ (b)   months and ​ (c)   density bands indicate ​ (d)   months.

• summer
• winter
• high
• low
• stress
• irregular

What can be seen in the coral core x-ray image?

• Stress Bands

• Annual Banding

• Irregular Banding

• A Growth Hiatus

According to this coral core sample, what occurred in 1998?

• Increased River Discharge

• Coral Bleaching Event

What does the intensity of the luminescence tell us about what occured in 1991?

• Increased River Discharge

• Coral Bleaching

A distinctive dark line or irregular banding can indicate a growth what?

• reduction

• expansion

• hiatus

• period

Which statement best describes -the response of complete the macroalgal cover (green), coral cover (orange) and topographic complexity following a coral bleaching event.

• Coral bleaching caused an increase in coral cover which resulted in an increase in the amount of macroalgae cover. Overtime the reef recovers and there is an increase of structural cover, and fish habitat.

• Coral bleaching caused a decrease in coral cover which resulted in an increase in the amount of macroalgae cover. Overtime a phase shift occurs resulting in a loss of structural cover, and fish habitat.

• Coral bleaching caused an increase in coral cover which resulted in a decrease in the amount of macroalgae cover. Overtime a phase shift occurs resulting in a loss of structural cover, and fish habitat.