Calcium

Definition

Calcium is a chemical element with the symbol Ca and atomic number 20, which is an essential nutrient and a major component of seawater. It plays a vital role in marine ecosystems, particularly in the formation of shells and skeletons of marine organisms like corals and mollusks, and it also affects the overall chemistry and biological processes in ocean waters.

5 Must Know Facts For Your Next Test

1. Calcium is one of the most abundant elements in seawater, typically present at concentrations around 400 mg/L.
2. In marine ecosystems, calcium is crucial for the growth of calcareous organisms, enabling them to create protective shells and structures that provide habitat for other marine life.
3. Calcium ions can influence the solubility and precipitation of other minerals in seawater, affecting the overall mineral composition and biological availability.
4. Marine organisms use calcium for various physiological processes beyond calcification, including muscle function and neurotransmission.
5. The balance of calcium in seawater can be affected by factors like temperature, salinity, and biological activity, all of which play a role in shaping marine habitats.

Review Questions

• How does calcium contribute to the process of calcification in marine organisms?
  • Calcium is essential for calcification as it provides the necessary ions that marine organisms, like corals and mollusks, use to form calcium carbonate structures. This process allows them to create shells and skeletons that are critical for their survival and growth. The availability of dissolved calcium ions in seawater directly impacts how efficiently these organisms can build their structures.
• Discuss the impact of ocean acidification on calcium availability for marine organisms.
  • Ocean acidification occurs when excess CO2 dissolves in seawater, leading to lower pH levels. This process decreases the concentration of carbonate ions, which are essential for organisms that rely on calcium for building their shells. As a result, calcifying organisms face challenges in maintaining their structures, potentially leading to decreased biodiversity and altered marine ecosystems.
• Evaluate the role of calcium in influencing marine ecosystem dynamics and its importance in addressing climate change impacts.
  • Calcium plays a significant role in marine ecosystem dynamics by supporting the growth and sustainability of calcifying organisms that are foundational to many marine food webs. Its importance is further underscored when considering climate change impacts; as ocean acidification alters calcium availability, it can disrupt species interactions and ecological balance. Understanding these connections is crucial for developing strategies to mitigate climate change effects on marine biodiversity and ecosystem health.

Related terms

Calcification:

The process by which marine organisms, such as corals and shellfish, build their calcium carbonate structures from dissolved calcium ions in seawater.

Ocean Acidification: The decrease in pH levels of the ocean due to increased atmospheric CO2, which reduces the availability of carbonate ions necessary for calcification.

Seawater Chemistry: The study of the chemical composition of seawater, including the concentrations of various ions such as calcium, which influence biological and physical processes in marine environments.