3 Laws of Nature3 Laws of Nature

1.1. Everything is interconnected.Everything is interconnected.

2.2. Everything is always changing.Everything is always changing.

3.3. Everything must go somewhere.Everything must go somewhere.

An An ecosystemecosystem is an area where living things is an area where living things interact with the environment, functioning as interact with the environment, functioning as an entire unit.an entire unit.

All ecosystems are "open" systems in the All ecosystems are "open" systems in the sense that energy and matter are transferred sense that energy and matter are transferred in and out. in and out.

EcosystemsEcosystems

Biological OrganizationBiological Organization

Biological OrganizationBiological Organization

Abiotic & BioticAbiotic & Biotic All ecosystems contain interacting abiotic All ecosystems contain interacting abiotic

(non-living) and biotic (living) parts.(non-living) and biotic (living) parts.

Abiotic Parts (Lithosphere, Atmosphere,

Hydrosphere)

Climate - temperature - precipitation

Soil - minerals

Landscape

Atmosphere

Water

Sun

Biotic Parts (Biosphere)

Plants

Animals

Microbes

Fungi

Humans

Producers

Consumers

Decomposers

Energy Flow ThroughEnergy Flow ThroughFood ChainsFood Chains

Minerals

Producers Consumers

Decomposers

Energy for LifeEnergy for Life

PhotosynthesisPhotosynthesis (Plants) (Plants)

Carbon dioxide + Water Carbon dioxide + Water GlucoseGlucose + Oxygen + Oxygen

RespirationRespiration (Animals & Plants) (Animals & Plants)

Glucose + Oxygen Glucose + Oxygen EnergyEnergy + Carbon dioxide + Water + Carbon dioxide + Water

Sun

Energy PyramidsEnergy Pyramids

Energy Pyramid

Food Web – A more accurate Food Web – A more accurate picturepicture

Symbiotic InteractionsSymbiotic Interactions

MutualismMutualism – both organisms benefit – both organisms benefit

CommensalismCommensalism – one benefits, the other is – one benefits, the other is

not harmednot harmed

ParasitismParasitism – one benefits, the other is – one benefits, the other is

harmedharmed

Invasive SpeciesInvasive Species

Invasive SpeciesInvasive Species

They They thrivethrive in their introduced environment in their introduced environment because they:because they:

1.1. have no natural enemies.have no natural enemies.

2.2. adapt well to their new habitat and find adapt well to their new habitat and find an abundance of food and shelter.an abundance of food and shelter.

3.3. have good reproductive success.have good reproductive success.

4.4. have an extensive range of tolerance.have an extensive range of tolerance.

Hence, they have very few limiting factors.Hence, they have very few limiting factors.

Invasive Species continued…Invasive Species continued…

They They harmharm the existing ecosystem they are the existing ecosystem they are invading by:invading by:

a.a. out-competing native species for food and out-competing native species for food and space.space.

b.b. upsetting the balance of interactions in the upsetting the balance of interactions in the food web.food web.

c.c. lowering the overall bio-diversity of the lowering the overall bio-diversity of the ecosystem since native species can eventually ecosystem since native species can eventually become extinct.become extinct.

They can also become a pest to humans when They can also become a pest to humans when they eat crops or become a nuisance in our they eat crops or become a nuisance in our homes, businesses and recreation areashomes, businesses and recreation areas..