Ecosystem and conservation Flashcards
Why is conservation bio becoming a distinct discipline
Increased concern over plant degradation
realisation of the extinction crisis
realising the need for intergrated sustainable land management to solve problems
First principle of conservation bio
Evolution is the basic axiom that unites all of biology.
(The evolutionary play)
2nd principle of conservation Bio
The ecological world is dynamic and largely
unbalanced.
(The ecological theatre)
3rd principle of conservation Bio
The human presence must be included in
conservation planning.
(Humans are part of the play)
Natural science involved in conservation bio
Genetics
Pop bio
Biogeography
ecology
Applied science involved in conservation bio
Agriculture
wildlife bio
forestry
Social science involved in conservation bio
law
economics
Sociology
Ecophilosophy
Species richness?
Total species number
Eveness meaning in bio diversity context…
Relative abundance of species
3 levels of biodiversity
Genetic diversity
Species diversity
Ecosystem diversity
Genetic diversity…
comprises genetic
variation within a population and between populations
Ecosystem services
Ecosystem services are goods (such as food) and services (such as waste assimilation) that human populations utilise
Four fundamental types of ecosystem service:
provisioning
regulating
cultural
supporting
Provisioning services (products obtained from
ecosystems):
Food, freshwater, fuel, fibre, biochemicals, genetic
resources
Regulating services (benefits obtained from regulation
of ecosystem processes):
Climate regulation, disease regulation, water regulation,
water purification, pollination
Cultural services (non-material benefits obtained from
ecosystems):
Spiritual & religious, recreation & ecotourism, aesthetic,
inspirational, educational, sense of place, cultural
heritage
Supporting services (services necessary for the
production of all other ecosystem services):
Soil formation, nutrient cycling, primary production
Biodiversity hotspot
A biodiversity hot spot is a relatively small area with a great concentration of endemic species and many endangered and
threatened species
Native/indigenous species:
- Species that naturally occur in an area. Have reached
the area of their own accord.
Endemic species:
Native species that do not occur anywhere else in the
world
Exotic/alien/introduced/non-native species:
Species that have been brought to an area by humans.
Naturalised species
- Exotic species that maintain wild populations
Invasive species
Naturalised species that are spreading rapidly, and
having negative impacts
Global diversity change drivers
- Climate change
- Over-exploitation
- Pollution
- Habitat loss
- Invasive species
Direct effect of climate change
- loss of native species that are unable to move to suitable sites
- invasion of exotic species (plant, animal, fungal)
Increased incidence of extreme weather events - loss of native species due to extreme conditions (drought, frost etc)
- small isolated remnants are especially vulnerable to damage from
extreme events (windstorms, floods etc)
Indirect climate change effects
Competition with invasive species
Increased disturbances at landscape scale (especially fire)
Reduced funding for biodiversity conservation due to socio-economic effects of climate change (e.g. cost of maintaining infrastructure like roads)
Over-expoloitation
is human harvesting of wild plants or animals at
rates exceeding the ability of populations of those species to rebound e.g fish// tuna
Polynesian settlement habitat loss
Key sources of evidence
Charcoal and wood
Soil instability
Pollen
Oral traditions
Reasons for deforestation
Moa hunting not important
Agriculture (bracken and kumara)
Security around Pā sites
Facilitate travel routes
Accidental
European settlement habitat loss
Much broader then the polynesian
Major drivers of habitat loss
Forest clearance for timber
Forest clearance for agriculture
Shrubland/grassland burning & cultivation for agriculture
Wetland draining for agriculture
Habitat loss also occurred as a result of invasive species
Accidental invasions (e.g. marram into sand-dunes)
Deliberate invasions (over-grazing in tussock grasslands)
Read invasive species slide lecture 30-31 side 35
raaa
Ecosystem ecology is dependant on…
organisms + abiotic
environment. Fluxes of matter and energy
Net prinmary production equation
NPP=GPP-R
Decomposition has what relationship to tropic levels
Decomposition links all tropic levels
Marine limiting factors of NPP..
Light, N, Iron
Freshwater NPP limiting factors…
Light, P
Terrestrial limiting factors
water, temp, N, P
Energy transfer// trophic levels
Energy transfer between trophic levels only 10% efficient
green world hypothesis
Herbivores consume a small percentage of
vegetation:
Green world hypothesis is due to herbivores being limited by..
– plant defenses
– nutrients
– abiotic factors (e.g. temperature)
– interspecific competition
– intraspecific interactions (e.g. predation)
Biogeochemical process/ nutrient cycling
essential elements of living matter are circulated from the nonliving compartment to living
litter decomposition varies due to..
– plant leaf traits (e.g. specific leaf area, leaf
nutrient concentrations)
– global drivers (e.g. temperature, moisture)
Human pop impacts
disrupting chemical cycles throughout the biosphere.
by removing nutrients from
one part of the biosphere and then
adding them to another.
human pop toxic chemical impacts
Toxins can become concentrated in
successive trophic levels of food webs
These toxins, are ingested and metabolized by the
organisms in the ecosystems and can accumulate in the
fatty tissues of animals.
And through bio magnification become concentrated going through tropic levels of the food web
Current Anthropocene
Is a decisive break from previous periods of Earth’s history (proposed as a new
geological epoch)
carbon dioxide high level
land change irreversible land damage
Challenges in climate change
Corruption and entrenched political influence of big oil etc
Poverty/wealth inequality
Climate change despair
CO2 already in atmosphere and feedback systems
Human activities on ecosystems
Humans population growth is the key driver of global environmental change
Human activities are altering many aspects of ecosystems globally
The most significant of these is global climate change
resulting from CO2 emissions
Earth has now entered a new Epoch
the Anthropocene
