IB Environmental systems and societies 4.3B Consumption of Organisms from Freshwater and Marine Environments Notes

Aquatic Organisms Are a Vital Source of Human Food

1. Humans depend heavily on aquatic organisms, both flora (plants and algae) and fauna (fish, shellfish, and invertebrates), as food.
2. These foods supply vital proteins, vitamins, minerals, and fatty acids for human nutrition.
3. What people eat varies by region, depending on culture, resource availability, and sustainability.

Aquatic Flora Consumed by Humans

1. Watercress (Nasturtium officinale), local example
   1. A freshwater plant widely grown in Europe, especially the UK.
   2. Cultivated in shallow streams or hydroponic systems with clean, flowing water.
   3. Eaten raw in salads or cooked in soups, and rich in vitamins A, C, K, and calcium.
2. Nori (Pyropia spp.), global example
   1. A marine red alga cultivated in coastal Japan, Korea, and China.
   2. Dried and pressed into thin sheets for sushi, snacks, and condiments.
   3. Rich in iodine, iron, and protein, and a major aquaculture export.

Aquatic Fauna Consumed by Humans

1. Queen conch (Aliger gigas), local example
   1. A large marine mollusc from the Caribbean Sea and parts of the Atlantic.
   2. Eaten as a delicacy in dishes like conch chowder and fritters.
   3. Overharvested for meat and its pink shell, and now protected under CITES Appendix II.
2. Tilapia (Oreochromis niloticus), global example
   1. A freshwater fish native to Africa, now farmed worldwide.
   2. Raised in aquaculture for its rapid growth and mild flavour.
   3. One of the most farmed fish globally and a key source of affordable protein in Asia, Africa, and Latin America.

Rising Demand: Seafood Is Outpacing Population Growth

1. Global seafood demand is rising faster than population growth, driven by economic development, health awareness, and cultural globalization.