week 5: disturbance ecology Flashcards
define ecological disturbance
something that happens that kills organisms and changes occur
what are some examples of ecological disturbances?
- fire, wind, blowdown, climate change
- small or large scale
give an example of small scale disturbances
-flooding, windthrow, tree death, frost, compaction, roads ect.
what type of disturbance is Lake Kaindy and example of?
small; submerge forest , water so cold–> no decomposition of trees
what happens after a disturbance event? what plants arrive first?
succession ; ???
how do plants arrive during the succession?
- seedbank
- seeds germinated by fire
- seed dispersal by wind and animals
- seeds moved by disturbance
t or f: disturbance is a temporary change in an average env’tal conditions
false; disturbance is the average
-if species don’t adapt, won’t survive ie disturbance can influence community- level diversity
how does diversity and disturbance interact?
-increase in diversity - decrease in disturbance
-disturbance creates diversity which reduces disturbance
“chicken and egg”
name one species that benefits/ needs a fire disturbance to survive
- jack and pitch pine; seeds dont open until 400 c
- lack of fire in boreal forest IS disturbance
- pitch pine decreasing in ON
name the small scale issues that come with people clear cutting ( disturbance via people)
-aesthetics, $$m weathering, erosion, microclimate
describe the large scale issues with disturbance via people?
economies, societal benefits, climate change
give an example of societal impacts from disturbance
-border of haiti and Dominical republic; deforestation of haiti show differences in policies and social programs reflect on landform
describe a big ecological disturbance
Ice Age
ex Osage Orange –> originally from north, got pushed to Texas, no animal eats it, can’t disperse
describe the four big biological disturbances
- european settlement
- Chestnut Blight
- Dutch Elm disease
- Emerald Ash Borer
describe the overall impact of invasive species
- reduce diversity of plant and animal species –> put natives at risk by ‘crowding out’
- costs Can $34.5 billion annually
how can we prevent future catasprophe of our ecosystems?
-increase biodiversity–> allows life t oadapt to changing env’tal conditions including large changes
define biodiversity?
variety of genes, organisms, species and ecosystems in which organisms exist and interact
what effect foes biodiversity have on the ecosystem?
- increase stability in an ecosystem
- increases productivity
- decreases susceptibility to biotic invasions
what are the consequences of a shrinking habitat?
lose niche space;
- only tiny populations can exist in tiny habitats
- tiny populations are vulnerable to exinctino
t or f non-native plants support more insects than native
false; insects wont eat ‘alien’ plants
-most insects can only develop and reproduce on plants they share evolutionary history
–% of all phytophagous insect species eat plants in _ or fewer species
90%, 3
what should we designers consider when making a planting plan?
-plant species that support the most insect biodiversity
what 3 things must we do to share suburbia with wildlife?
- create corridors connecting natural areas
- reduce the area now in lawn
- begin the transition from alien ornamentals to native ornamentals
