Week 1 - Module 1 (Lec 1)
Earth's ecosystem
What is an ecosystem?
Energy flow and production
Biodiversity and ecosystem functioning
The distribution of ecosystems
Ecosystem is a defined community containing a mix of living organisms linked by energy and material transfer and interacting with its physical environment
Non-living = temperature, pH and water and
nutrient availability
Living = cellular organisms (i.e. bacteria,
archaea and eukarya) and viruses
Living and non-living = linked through nutrient cycles and energy flows
Photoautotrophs = Organisms capable of obtaining carbon and energy
also known as primary producers
Primary production
The process of converting inorganic carbon to
organic matter
Gross Primary Production
The total amount of solar energy captured by all of
the photoautotrophs in a given ecosystem combined
Net Primary Production
GPP minus energy use for respiration
Heterotrophs
rely on
obtaining organic carbon molecules from the environment
also known as primary consumers
Secondary consumers
eat primary consumers
succession of this = food chain
Solar flow, only 2% captured by photosynthesis, then 10% of that by primary and so on...
Ecosystem functions
The habitats, properties or processes of ecosystems.
Ecosystem Services
represent the benefits human populations derive, directly or indirectly, from
ecosystem functions.
functional groups
Groups of ecologically/functionally equivalent species
functional
redundancy
The presence of more than one species within a functional group
Biomes
rain forests, temperate forests and deserts