What are some major human impacts on aquatic ecosystems?

1. What are some major human impacts on aquatic ecosystems? Kakakakimmi & Geoffrey

2. Leaching • Natural leaching: nutrients seeps out of soil and causes it to flow into rivers and streams without the help of humans. • Chemicals from fertilizers and pesticides tend to leach and make the water unsuitable for life. • Sulfurous compounds make water more acidic and can cause acid rain. • Oil can cover plants and animals making them unable to fly or photosynthesize

3. Deforestation • Eliminates plants whose roots hold soil in place • Causes runoff and increases rate of erosion • Sediment from runoff clouds up water and affects photosynthesis • May cause floods from the lack of absorption into the soil

4. Dams • Affect fish migration and mating. • Floods ecosystems and dries others.

5. Excess nutrients • Fertilizers or other sources of nutrients raise the nutrient level and cause algae blooms. • Dead algae sinks and takes out oxygen from the water.

6. Agriculture and Irrigation • Grazing promotes runoff and increases sediment • Livestock have contaminants and potentially dangerous bacteria that can kill plants and animals. • Irrigation lowers water levels of rivers and streams

7. Debris (aka litter) • Choking hazard for birds and fish • Blocks sunlight from penetrating water • May seep out chemicals • Clogs waterways

8. Alien species • May become invasive and kill off native plants an animals • May cause extinction