Ecosystems Lecture 1 Part 2 (unfinished)

Ecosystem services

Benefits we obtain from the ecosystem

Provisioning services

Food, shelter, water, pharmaceuticals, chemicals, energy, etc.

Regulating services

Climate regulation, carbon sequestration, waste decomposition & detoxification, air & water purification, crop pollination, pest & disease control

Cultural services

Cultural, intellectual and spiritual inspiration, recreation, scientific discovery

Supporting services

Soil formation, primary production

Does energy flow through an ecosystem?

Yes

Does matter flow through an ecosystem?

No, it cycles within an ecosystem (recycled)

Where does energy come from?

Majority of energy comes from the sun

Primary producers

Autotrophs = self-feeders

• Photoautotrophs = sunlight + CO2 (photosynthesis by plants)

• Chemosutotrophs = oxidise inorganic compounds (H2S, NH3, Fe²+) + CO2

Consumers

Heterotrophs = other-feeding

• Herbivores

• Carnivores

Decomposers

Heterotrophs

• Detritivore = ingest and digest detritus (dead organic matter)

• Saprophytes = external digestion via enzyme discetion

How is energy processed?

1. Original energy source = light energy (sun)

2. Transformed into chemical-bond energy (photosynthesis and respiration)

3. Converted into heat energy – lost from system