Calcium

Definition

Calcium is a chemical element represented by the symbol 'Ca' and atomic number 20. It is an essential component of seawater and plays a vital role in various marine biological processes, including the formation of shells and skeletons in marine organisms. As a major ion in seawater, calcium contributes to the chemical balance and physical properties of ocean water.

5 Must Know Facts For Your Next Test

1. Calcium is one of the most abundant elements in seawater, typically found at concentrations around 400 mg/L.
2. In addition to supporting marine life, calcium plays a crucial role in regulating pH levels in ocean water through its interaction with carbonate ions.
3. The availability of calcium can be influenced by factors such as temperature, pressure, and salinity, which affect its solubility in seawater.
4. Marine calcifiers rely on sufficient levels of calcium for building their shells and skeletons; disruptions in calcium availability can lead to weakened structures and population declines.
5. Calcium also participates in biogeochemical cycles, influencing nutrient cycling and the overall health of marine ecosystems.

Review Questions

• How does calcium contribute to the chemical composition of seawater and influence marine life?
  • Calcium is a significant component of seawater, affecting its chemical composition by influencing pH levels and contributing to ionic balance. Marine organisms, particularly calcifiers like corals and mollusks, rely on calcium to form their calcium carbonate shells and skeletons. This dependence means that fluctuations in calcium levels can have profound effects on marine biodiversity and ecosystem health.
• Discuss the impact of changing ocean conditions on the availability of calcium and its implications for marine calcifiers.
  • Changing ocean conditions such as rising temperatures and increased CO2 levels can lead to ocean acidification, which reduces the availability of carbonate ions needed for calcification. As a result, marine calcifiers may struggle to maintain their calcium carbonate structures, leading to potential declines in populations and alterations in community dynamics. This impact not only affects individual species but can also disrupt entire marine ecosystems that depend on these organisms.
• Evaluate the role of calcium in the biogeochemical cycles within ocean ecosystems and its significance for overall marine health.
  • Calcium plays a critical role in various biogeochemical cycles within ocean ecosystems, notably through its involvement in nutrient cycling and buffering capacity. By participating in reactions that regulate pH and support the growth of calcifying organisms, calcium is integral to maintaining balanced ecosystems. An understanding of these processes highlights the importance of preserving stable environmental conditions, as disruptions can lead to cascading effects on marine health and biodiversity.

Related terms

Calcium Carbonate: A compound (CaCO3) that forms the primary structure of shells and coral in marine ecosystems, often precipitated from dissolved calcium in seawater.

Marine Calcifiers: Organisms such as mollusks, corals, and some plankton that utilize calcium to form calcium carbonate structures, which are essential for their growth and survival.

Salinity:

The concentration of salts in seawater, which affects the solubility and availability of calcium ions, influencing marine life and chemical processes.