Eutrophication

The video explains how excessive plant growth is caused by extra nutrients from fertilizers used in agriculture. These nutrients are washed into rivers or streams by rain, leading to rapid algae growth. This process results in a drop in oxygen levels, which kills fish and other aquatic organisms, creating dead zones where no life can survive.

What are the consequences of low oxygen levels in water bodies?

Describe what is meant by 'dead zones' in aquatic ecosystems.