Succession, Nutrient Cycles & Pollution Compare primary and secondary succession. How are matter and nutrients recycled through an ecosystem?

Succession – the predictable changes that an environment goes through as its being established or redeveloping Competition for light influences the stages of succession.

Primary Succession -

Stages of Primary Succession: Pioneer species – Lichens Mosses & Ferns Grasses Shrubs & small softwood trees Large hardwood trees (climax community)

Secondary Succession -

Keystone species – critical to homeostasis ex Keystone species – critical to homeostasis ex. Top predators (sharks, mountain lions), hummingbirds -pollinators Climax community – stable ecosystem in equilibrium or steady state Other Vocab

Nutrient Cycles Matter and Nutrients are recycled through an ecosystem. Energy, however, is replenished by the sun.

Turn and Talk Why are the Carbon Cycle, the Water Cycle and the Nitrogen Cycle so important to humans? (hint: biomolecules and cell transport)

Water Cycle Water occurs on Earth as a solid, liquid, and gas. PrecipitationAccumulationEvaporationCondensation

Water Cycle

Carbon Cycle Carbon is found in ALL living things- Organic Molecules Photosynthesis, Cellular Respiration, pollution are major components

Nitrogen Cycle Nitrogen makes up almost 78% of air. Every living organism needs nitrogen to make proteins & nucleic acids Nitrogen fixation caused by lightning & bacteria

Nitrogen Fixation N2 in the air is unusable Nitrogen Fixation- bacteria living on roots of legumes (bean family) convert N2 to NH3 “Fixed” Nitrogen NH3 “Fixed” Nitrogen is then passed from consumer to consumer along the food chain The nitrogen is then “reused”

Eutrophication of a lake

Algal bloom leads to dead zones. Causes: fertilizer runoff, wastes in water, increased water temp.

Nutrient Cycling Stations

Toxic Chemicals Nonbiodegradable materials CANNOT be broken down in nature, remain in environment Ex. Glass, plastic, Styrofoam, DDT Biological magnification concentration of harmful nonbiodegradable substance increases as it moves up food chain

Biomagnification of DDT Video

Biological magnification Fish-Eating Birds Magnification of DDT Concentration 10,000,000 100,000 10,000 1,000,000 1 1000 Large Fish Small Fish Zooplankton Producers Water Biological magnification

2 main causes of pollution Increase in human population Demand for better lifestyle

Endangered Species Organisms threatened with extinction Caused by hunting, disease, pollution, habitat destruction Ex. Sea turtles, Ivory-billed woodpecker

Ten Animals that May Go Extinct Video