Final material Flashcards
(136 cards)
Week 9 What are 4 natural ecological disturbances? What are four anthropogenic ecological disturbances?
Natural- Wildfires, Floods, inwd storms, drought
Anthropogenic- Invasive species, deforestation, habitat fragmentation, pollution
Are daily freeze thaw cycles small scale events?
yes
Are glaciations small scale events?
no, large scale events
are animal disturbances small scale events?
yes
Define disturbance?
Is a relatively discrete event in time that changes the structure of poplns, communities, and ecosystems, which causes changes in resource availability or the physical environment
What’s the difference between novel disturbances and frequent ones?
novel rare (for ex invasive species), frequent are casual
What is resilicience?
properties of ecosystem to enhance their capacity to sustain structure and function
What is the definition of ecological succession?
is the process of regrowth following a perturbation that open up a large space
Explain primary succession?
is when you just have rock which then goes to non living to forest community.
The pioneer stage is dominated by lichens, the intermediate stages are dominated by grasses and shrubs that are shade intolerant, and the climax community has shade tolerant trees
Explain secondary succession?
You start off with some degree of soil, get event like natural fire, and then get pioneer species, intermediate species, and climax community at a much faster time scale than primary succession.
What happens to the soil properties during succession? What do we see a increase in?
soil depth
nitrogen
organic matter ‘moisture retention
What happens to the soil properties during succession? What do we see a decrease in?
see decrease in pH and phosphorus
What ecosystem changes do we see during succession? What is increased?
biomass
primary production
nutrient retention
What are the three mechanisms that drive ecological succession? describe them
Facilitation (one species modifies the area which then allows other species to live there)
Inhibition (species modifies the area so that later species are inhibited through competition, parasitism, predation
Tolerance (species live in the area under stress and don’t effect settlement of other species)
What are the four phases of species in successional stages? Give examples
Establishment phase (ex grasses)
Early succession phase (ex shrubs)
transition phase-mid succesion phase (young forest, pines)
climax (mature forest)
What is a regime shift?
when the resilience of an ecosystem is exceeded, ie the boundaries and ecosystem condition are exceeded
High resilience ecosystems have what kind of diversity?
high diversity
When did Alberta experience an extreme fire season?
in 2019
What are the adaptations trees have to fire? List the four
serotinous cones (need heat to release seeds)
fire resistant bark
Crown sprouting (part of crown burns and causes dormant buds to grow)
Basal sprouting (subtearran buds regrow)
What are the 4 benefits of forest fires?
They promote plant diversity
It controls competition (by removiing dominating species)
it thermally prune slower limbs (good because they don’t acc provide energy, can’t get sunlight cause of shade.
Controls insect and disease by wiping the slate clean
What five things are needed for fire to be enacted as a management practice?
Low intensity fires
Supporting plants for food and basketry
Clearing out underbrush (reduces fire fuel)
facilitate shunting
knowing the history of fire suppression
What four things do forest fires get described by?
type (ground, surface, crown fire (which are hot and travel from surface and have intense long lasting damage)
frequency (more litter result in more frequency)
size
Intensity
How is climate change impacting fires?
It’s increasing wildfire season, increasing wild fires risk by driving up temps and making forests drier, and burning more land
Week 10 What is landscape heterogeneity?
Is patchiness (is areas that are similar), that are spatially complex