Chapter 4 Flashcards
Niche
Role of an organism in an ecosystem
Niche consists of
What eats you, what you eat where you live, where you breed, when you are active
Why do animals not have similar niches?
Can lead to competition
Why are exotic species not good for ecosystems
Because they lack natural predators to keep the m from over competing the native species. Naturally or from human transportation
What are biomes?
A large geographic are that has specific climate withplants and animals adapted to the area.
What are the four majour biomes in Canada>?
Grasslands, Tundra, Taiga, Desidedeous forest
Biomes in Alberta
Muskeg, Tiaga, Grasslands, Desidedeous forest,
What varys at the bottom of lakes?
Tempurature, light, oxygen, and amount of organisms.
Littoral zone
Frpm the lake shore to the point where you find no more plants. Most productive part of the lake where algae and plants use sunlight for photosynthesis.
Limnetic zone
Area of open where there is enough lit for photosynthesis most lite can be done
Profundal zone
Deepest part of the lake where no light is available
What are plankton?
Autorotrophs and heterotrophs
What are the layers of soil going in order
Litter, top soil, subsoil, bedrock
Soil
Determines what plants ca grow and affect biodiversity
Available water
deters what is able to grow in the soil
Temperature and sunlight
Derters what can live in an area. More sunlight means more photosynthesis
Factors affecting aquatic ecosystems
Chemical evironment (fresh water or salt), Amount of dissolved oxygen, Water pressure
What is an ecotone?
Two areas where both ecosystems meet
What happens in the spring?
THe ice melts and oxygen can dissolve into the water and is stirre into the waves. the cold surface water warms. As it reaches 4°C, it sinks carrying its dissolved O2 with it.
This mixing process is called spring turnover
What happens in the winter?
Water is covered in iced acting as insulator. When there is a lot of snow coverage, no light penetrates, meaning lower oxygen levels.
What happens in the Summer
As the surface water warms above 4°C, it won’t sink. Layers are set up again. There is little movement of O2 from the surface to the depths in the summer. Organisms in
the hypolimnion (bottom level) must rely on O2 reserves brought down during the spring turnover.
* The epilimnion (Top level) may also face an O2 problem. As the water warms up, it can’t hold as much
dissolved O2. During a hot spell, a shallow lake may lose too much O2 that some species (ie.
Lake trout) may die.
What happens in the fall?
Temperatures drop. The surface water cools. When it reaches 4°C, it sinks. This fall turnover renews dissolved O2 levels at lower levels
Biotic potential
How quickly a population can increase in size if conditions were perfect. The four factors are birth potential,
Birth potential
Maximum amount of offspring per each birth potential, capacity for survival, b
Capacity for survival
Number of offspring that reach a reproductive age.
Breeding frequency
Number of times that a species reproduces each year
Length of reproductive life
Age of sexual maturity and the number of years the organism can reproduce
Limiting factors
Factors in the environment that prevent
populations from attaining their biotic potential. Any resource that is in
short supply is a limiting factor.
Carrying capacity
The maximum number of individuals of a species
that can be supported by an ecosystem
Limits of tolerance
an organism can survive within (tolerate) a
particular range of an abiotic factor; above and below this range, it
cannot survive.
Law of the minimum
The nutrient in the least supply is the one that
limits growth
Law of tolerance
THe range in which a species can survive
Density dependent
Affects a population because of the density of the population tends to be biotic. e.g. how much food is available
Density independant
Affects population and is usually abiotic. Does not occur because of the density. e.g. Floods
Oliotrophic
Deep and cold lake that ha, few nutrients less life.
Eutrocentric
Lakes shallow and warm that has many nutrients, more life
What are indicators of water quality
Bacteria: indicate animal waste and harmful bacteria
Dissolved oxygen: lower levels supply less life
Biological Oxygen Demand
A measure of how quickly oxygen has been used up. High levels of BOD mean less oxygen
