Directions: Use the information provided and your knowledge of Life Science to answer the following questions. Show all work where necessary.
Directions: Use the information provided and your knowledge of Life Science to answer the following questions. Show all work where necessary.
Coral reefs are among the most diverse ecosystems on Earth, but they are increasingly threatened by rising atmospheric carbon dioxide (
Diagram 1.
Source: https://www.britannica.com/science/ocean-acidification
Corals grow by creating hard skeletons, and this process requires a steady supply of carbonate ions. When pH declines, the ocean becomes more corrosive to carbonate-based structures and reduces coral growth rates. As acidification increases, many species of coral struggle to repair damage, reproduce successfully, or maintain their structures. These stresses make corals more vulnerable to disease, storms, and warming temperatures.
The decline of living coral cover has cascading effects throughout the ecosystem. Coral reefs provide habitats and shelter for thousands of species, from fish and crustaceans to sponges and mollusks. As corals die, the complexity of the reef decreases, reducing habitat space and causing many dependent species to decline or disappear. In some regions, reefs have already lost over half of their coral cover, resulting in major losses of biodiversity.
Diagram 2.
Source:
https://www.e-education.psu.edu/earth103/node/649
Data from long-term monitoring show strong relationships between decreasing pH levels and coral decline. For example, between 1980 and 2020, ocean pH dropped by about
These patterns demonstrate how environmental change - in this case, ocean acidification driven by human activity - can lead to both declines in species numbers and local extinctions. If current trends continue, scientists project further reductions in coral growth, additional species losses, and a risk that some reef ecosystems could collapse entirely.
Table 1.
Year | Average Ocean pH | Living Coral Cover (%) |
|---|---|---|
1980 | 8.11 | 42 |
1990 | 8.08 | 38 |
2000 | 8.05 | 33 |
2010 | 8.03 | 27 |
2020 | 8.01 | 18 |
2030 | 7.98 | 10 |
Graph of Information - Figure 1.
Table 2.
Reef pH Level | Coral Species Richness |
|---|---|
8.1 | 220 |
8.05 | 185 |
8 | 140 |
7.95 | 90 |
Graph of Information - Figure 2.
Using Table 1, describe the relationship between average ocean pH and living coral cover from 1980 to 2030. What overall trend is shown in the data?
Based on Figure 1, which statement best describes the decline in coral cover over time?
Using evidence from Diagram 1, explain how decreasing pH affects the availability of carbonate ions. How could this chemical change influence coral growth?
Make a claim about how ocean acidification affects coral reef biodiversity.
Include a claim, evidence, and reasoning.
According to Table 2, which pH level is associated with the lowest coral species richness?
Compare the trends shown in Figure 1 and Figure 2. How do changes in pH relate to both coral cover and species richness across the data provided?