Module 5: Biodiversity and Ecosystem (De)stabilization Flashcards
why is it important to be concerned about the current rate of biodiversity loss (3)
- biodiversity is needed to maintain human wellbeing
- responsibility to protect who we share Earth with
- biodiversity is beautiful
biodiversity
- the variety of forms of life, from genes to species, through to the broad scale of ecosystems
genetic diversity (2)
- all different genes contained in all living species
- includes genes inside plants, animals, fungi, and microorganisms
species diversity
- all of the different species as well as the differences within and between species
why is species diversity a harder to analyze then other diversity types (2)
- species are defined by us
- challenging to determine loss/extinction
ecosystem diversity
- all different habitats, biological communities, ecological processes, and variation within individual ecosystems
is biodiversity uniform across the globe (2)
- not uniform due to the availability of limiting factors across the globe
- bottom of the food chain must be established before the top of the food chain can develop
what are some limiting factors for biodiversity (2)
- water
- sunlight
where is the most biodiversity on earth (2)
- near the equator where sunlight and water is abundant
- more diversity near shore (shallow seas) as there is more access to sunlight
ecosystem (2)
- a biological community of interacting organisms and their physical environment
- both biotic and abiotic components
what is the stock of an ecoSYSTEM
- it can be biodiversity
what makes an ecosystem a good candidate to be a system (3)
- it is full of interconnections
- lots of influencing factors that create emergent properties that cannot be studied as individual component
- contains lots of feedback loops
what kind of feedback loop is the nitrogen cycle
- balancing/stabilizing feedback loop
what is driving biodiversity loss (2)
- land use conversion
- temperature changes
global biodiversity loss
- over 58% of world’s land surface has experienced biodiversity loss significant enough to threaten ecosystem function
how has biodiversity loss affected the ecoSYSTEM
- emergent properties/function is becoming damaged
what is the relationship between biodiversity and ecosystem function (2)
- positively related; more biodiversity will allow for higher ecosystem functioning
- more species allow for greater stability of the ecosystem
ecosystem function (2)
- the collective life activities of plants, animals, and microbes and the effects of these activities
- feeding, growing, moving, excreting waste, etc all have physical and chemical effects on the environment
old paradigm of biodiversity and ecosystem functioning (2)
- environmental variation drives biodiversity and ecosystem functioning
- environment affects biodiversity and ecosystem function, and ecosystem functioning affects biodiversity, but biodiversity does not affect the other sphered
what was studied to change the old paradigm of biodiversity and ecosystem functioning
- isolating effects of biodiversity on ecosystem functioning
what is the new paradigm of biodiversity and ecosystem functioning
- biodiversity and environmental variation jointly drive ecosystem functioning
how does having more species make ecosystems more stable (2)
- different species will vary in responses to environmental fluctuations
- allows for persistence of functionalities despite stressors on system
species richness
- number of species present
species composition
- identity of species present
insurance hypothesis (2)
- when different species are present, they are able to fulfil a variety of ecological niches within an ecosystem
- by contrast, with monocultures, all of the individual plants are competing for the resources held within one specific ecological niche
how does the subsystem (species) serve the larger system (ecosystem) (3)
- species stability is lower when more species are present within the same niche
- ecosystem stability is higher when more species are present within the same niche
- species lose out to support ecosystem, but this inevitably supports the species again as the ecosystem is stable
what happens if one species stability increases significantly overtime (eg. invasive species) (2)
- sub-optimization; subsystem benefits at the cost of system
- ecosystem stability will go down and may collapse
resilience
- ability of an ecological system to return to its initial state after being changed in some way
resilience vs stability (2)
- stability is staying at ONE stable state
- resilience can be described as bouncing from each stable state
the adaptive cycle (3)
- dynamic systems do not tend towards some equilibrium state
- they pass through characteristics phases of growth, conservation, collapse, and renewal
- this cycle does not tend towards stability, but rather resilience
the adaptive cycle: coral reef (2)
- coral has went extinct and come back/evolved multiple times
- for humans, this evolution is not short enough to be relevant, so we need to find a solution to stop reef from hitting tipping point
tipping points
- critical threshold where a small change has a large, long-term consequence for a system
why are tipping points useful
- predicting point in time where the system moves from one state to the next
resilient ecosystem vs vulnerable system: tipping points (2)
- troughs are much deeper in resilient systems
- vulnerable systems have shallow troughs following by a deep regenerative trough that is too long to be significant to humans (eg. desert state)
what systems are approaching tipping points that are concerning to humans (2)
- coral reefs becoming bleached
- fish stocks collapsing
extinction (trophic) cascade
- well-ordered ecosystems can become disordered in a cascade-like way when biodiversity is impacted
extinction trophic cascade: whales (7)
- overharvesting of plankton-eating whales allows plankton-eating and less nutritious fish to thrive
- nutritious fish are outcompeted by plankton-eating fish
- sea lions and harbor seals decrease as less nutritious fish cannot sustain them
- killer whales don’t have enough pray and being to prey on sea otters
- sea otters decline
- sea urchins, the food source of sea otters, increases
- kelp forests are thinned by sea otters and can no longer support fish eaten by eagles….etc, etc
how do giant kelp forests support biodiversity (2)
- similar ecosystem type to coral
- persistent giant kelp forests create and modify habitats, year after year
how does loss of kelp forests affect biodiversity (3)
- changes coastal biodiversity
- more understory seaweeds, sponges, anemones, and sea fans
- fewer fishes, invertebrate carnivores, and invertebrate herbivores
functional redundancy
- when there is more than one species with a similar ecological role in a system
- allows for greater resilience of the ecosystem
species composition vs species richness (2)
- species composition may be more important than species richness
- species composition is the identity of the species, whereas species richness is the amount of species in general
ecosystem services
- conditions and processes through which natural ecosystems, and the species that make them up, sustain and fulfill human life
ecosystem functions vs service (2)
- function: all emergent properties
- services: category of emergent properties beneficial to humans and would require payment or creation if the ecosystem did not exist
what are some ecosystem services (6)
- tourism
- food
- oxygen/nutrients
- substate stability (agriculture)
- water filtering and purification
- pollen deposition
how would humans replace ecosystem services
- synthetics services that require a lot of money and energy
Ecological/Green Economics (3)
- views economic activity as occurring within an environmental context
- economy is a subsystem of nature
- emphasis on preserving natural capital
how do green economics view economic growth (3)
- recognize that economic growth cannot continue indefinitely
- growth is limited by carrying capacity of the earth’s ecosystem
- value a steady state economy/circular economy
how does the green economy achieve a circular economy (5)
- equitable distribution of goods and services
- incorporations of social values in decision-making
- improvement of human well-being
- social justice: inclusion of marginalized groups
- concern for future generations
what aspects of the economy and environment are connected (4)
- human activities and economic/cultural benefits
- global changes: biogeochemical cycles, land use, species invasion, and biodiversity
- ecosystem processes
- ecosystem good and services
