Cycling of matter Water, nitrogen, carbon and more!

What is cycling?  The constant reuse of matter  May be found in biotic and abiotic components of the ecosystem at different times

Biogeochemical cycles  Carbon, nitrogen, phosphorus  Bio = alive (or part of an organic compound at some stage of cycle)  Geo = present in non-living parts of environment  Chemical = is a chemical substance

Carbon cycle

Nitrogen cycle

Phosphorus cycle

Human interference  Some mineral nutrient cycles are disrupted by human intervention eg. Logging of trees removes phosphorus, magnesium and calcium Soils depleted of nitrogen due to over- cultivation (growing too many plants)

Water cycle  As well as biogeochemicals, water also cycles in ecosystems

Bioaccumulation (biological magnification)  Chemicals that do not biodegrade (break down) build up in organisms through the trophic levels Algae has concentration of 3 ppm (parts per million). For simplicity, we will call this 3 per cell Shrimp consumes millions of algae cells in lifetime Cod consumes thousands of shrimp Ringed seal consumes thousands of cod Polar bear consumes hundreds of seals. There has been no break down or excretion of toxin 3 toxins 3, 000, 000 toxins 3, 000, 000, 000 toxins 3, 000, 000, 000, 000 toxins 300, 000, 000, 000, 000 toxins

Activities Glossary: biogeochemical, carbon cycle, nitrogen cycle, phosphorus cycle, water cycle, bioaccumulation, non-biodegradable Quick Check pg 467 Biochallenge pg 468, Chapter review (see term planner)