stability of ecosystems
what does the stability of an ecosystem mean
it is the ability of an ecosystem to maintain its structure & function over time, even though there are changes or disturbances
if an ecosystems is stable, then it will be able to resist changes that may disrupt its steady state
if there is a disruption that affects its structure of function, a stable ecosystem should be able to restore itself to its original state
what’re some examples of stable ecosystems
tropical rainforests
coral reefs
boreal forests
sonoran desert
tropical rainforests as an example of stable ecosystems
mature tropical rainforests (like Amazon, Congo) hv high biodiversity with complex food webs
these complex interactions allow rainforests to recover despite disruptions such as natural disasters
but recovery is slow
distribution & amount/abundance of species are typically constant over time
coral reefs as an example of stable ecosystems
are found in a variety of habitats, where they offer a home & food source to different organisms
are threatened by human actions, such as pollution & climate change
but some are still stable & continue to support diverse marine life
boreal forests as an example of stable ecosystems
also known as taiga
are characterised by coniferous trees & are home to lots of wildlife & plants
this diverse range of animals & plants helps maintain the balance of the ecosystem
are able to tolerate a range of environmental conditions, such as long, cold winters & short, warm summers
Sonoran desert as an example of stable ecosystems
supports a variety of life forms
bi-seasonal rainfall pattern supports more plant species than any other desert
cacti of the desert also provides food & shelter to many desert invertebrates & vertebrates
what are the 2 things that an ecosystem needs in order to maintain its stability over time
resistance - ability of an ecosystem to maintain stability regardless of disturbances
resilience - ability to recover after a disturbance
what’re some factors that contribute to ecological stability in ecosystems
energy supply
recycling of nutrients
climatic variables are within the tolerance levels
genetic diversity
accumulation of diversity is good cuz it means that if there is the loss of a particular species, it’s less likely to disrupt the stability of the ecosystem
energy supply as a factor that influences an ecosystem’s stability
energy is needed for all life processes
no energy supply = collapse of ecosystems
diversity of producers is something that controls the energy supply in food webs
since the producers are the organisms that convert sunlight into energy, which other consumers acquire through feeding on the producers
ecosystem with high diversity of producers = increased resistance to changes in biotic & abiotic factors
stable ecosystem also needs a balanced energy flow, which ensures that no species is dominant or scarce
recycling of nutrients as a factor that influences an ecosystem’s stability
recycling of nutrients is important for the long-term health of ecosystems
also allows for redistribution & regulation of nutrients
efficient recycling of nutrients = ecosystems can maintain nutrient availability = supports productivity of ecosystems
nutrient recycling also helps maintain diversity of ecosystem
biodiversity as a factor that influences an ecosystem’s stability
kinda already suggested this, but the more diverse an ecosystem is, the more likely it is to be stable
different types of biodiversity:
species diversity - ensures there’s enough species to fill the different roles in an ecosystem, contributing to its resilience
hving more than one species that performs similar roles, also allows for alternative pathways of flow in ecosystems
also means that if a species is removed, there’s other species to complete its role, so its absence doesn’t largely affect the ecosystem
habitat diversity - diversity within a geographical area
the more habitats there are, the more there may be species diversity, while means there are diverse interactions
ex - wetlands have diverse habitats, such as marshes, swamps, and bogs
genetic diversity - allows populations to hv a variety of genetic traits & variations
species with different traits hv different responses to environmental changes
these genetic variations also increase individual fitness, reproductive success & overall population health
climatic factors as a factor that influences an ecosystem’s stability
ecosystems that experience extreme physical changes, or experience extreme weather events, are less likely to be stable
climatic conditions determine the geographic distribution of species & composition of ecosystems
different species have different climatic needs or tolerances
changes in climatic conditions can lead to shifts in species ranges/tolerances, and change the composition of ecosystems
if a species can no longer tolerate a climatic condition, it may disrupt the stability of ecological communities
how do temperature & precipitation influence ecosystem productivity & nutrient cycling
temperature - affects plant growth, nutrient availability, & the rate of biochemical reactions
precipitation patterns - determine water availability, and thus influence plant growth & nutrient transport
whats a tipping point
a critical threshold in a system where a small change can hv significant & potentially irreversible effects
if an ecosystem reaches the tipping point, the ecosystem experiences a transformation, which leads to the loss of biodiversity, collapse of populations & degradation of ecosystem services
what are tipping points often associated with
often associated with hidden dynamics, where small changes can cause larger effects
whats an example of tipping points
deforestation of the Amazon rainforest
after a small amount of tree removal, remaining trees & vegetation can support the recovery of the cleared area
but the recovery is very slow & the resulting forest may differ in community composition & structure
when deforestation occurs at a higher rate, it can push the forest past a critical point, where its ability to regenerate & maintain its ecological stability is compromised
whats a consequence of deforestation of the Amazon rainforest
lack of absorption of water
trees absorb water from the ground through their roots & release it from their leaves as water vapour - process is called transpiration
this process is important as it forms clouds, allows for precipitation, & affects the water cycle, and removes large amounts of water from soil, preventing water-logged soil
more precipitation also allows more trees to grow, and these new trees will produce new precipitation (positive feedback)
note - a large area of forest is needed for transpiration
during transpiration, the released water absorbs heat from surrounding environment, cooling the surroundings
this cooling effect helps to regulate temperatures within the rainforest & can have larger implications for regional climate patterns
there is also uncertainty over the minimum area of rainforest that is enough to maintain the processes
how do you calculate the percentage change
(final value-initial value)/initial value X 100
can check kognity for example