Key components of a marine population system include:

1. Species Diversity: The variety of marine species, including fish, invertebrates, mammals, and plants, that interact within the ecosystem.
2. Population Dynamics: The study of how populations of marine organisms change over time due to factors like reproduction, mortality, migration, and environmental changes.
3. Habitat: The specific environments where marine species live, such as coral reefs, kelp forests, and deep-sea areas, which influence their population and health.
4. Interactions: Relationships between species, including predator-prey dynamics, competition, and symbiosis, which affect population sizes and ecosystem balance.
5. Human Impact: The effects of activities such as fishing, pollution, and climate change on marine populations and ecosystems.