1.explain various relationships with respect to food chains, food webs, and food pyramids,...
TRANSCRIPT
1. Explain various relationships with respect to food chains, food
webs, and food pyramids, including:producer consumer (herbivore, carnivore, omnivore)
predation (predator‐prey cycle) decomposers symbiosis (mutualism, commensalism, parasitism)
2. Describe the relationships between abiotic and biotic elements within an ecosystem, including air, water, soil, light, temperature (abiotic) and bacteria, plants, animals (biotic)
3. Design and analyse experiments on the effects of altering
biotic or abiotic factors (e.g., nutrients in soil: compare two plant types with the same nutrients, compare one plant type with different nutrients)
EcosystemHabitatCommunitySpeciesPopulationSymbiosisMutualismCommensalismParasitismPredationNicheCompetitionPredatorPrey Biodiversity
• By studying past and present ecosystems, we can better understand what may happen in the future.– Historical ecology is the study of natural and
written materials to better understand the ecology of a certain area.
– Many First Nations sources provide detailed knowledge of plants, animals, and natural occurrences of an area.
An ecosystem has abiotic components that interact with biotic components.– Abiotic (non-living) factors include air, water, soil, nutrients, and
light.– Biotic (living) factors include plants, animals, and micro-
organisms.– Ecosystems can take up many hectares of land or can be small,
such as a tide pool or a rotting log.
A habitat is where an organism lives.
The habitat of the red fox often includes the edges of forests or marshlands.
HABITATS
There are all sorts of different ‘habitats’ that different species
occupy:• The Blind Flatworm
& the eyeless shrimp
Live in dark caves. They are called “troglobites” (cave-
dwellers). They have adapted to darkness - do not require eyes...
White-Spotted Puffer Fish
• Lives in coral reefs (in tropical waters)Second most poisonous vertebrate
in the world...It’s muscles, skin, liver and ovaries
contain toxin 3x deadlier than cyanide.
The Rattle Snake
Occupies different habitats depending on the time of year...SUMMER WINTER
Open grassland (areas with high rodent density)
Hibernating dens (rock fissures or
caves)
• The abiotic components are what allow the biotic components to survive in an ecosystem– Abiotic factors include oxygen, water, nutrients,
light and soil.• Oxygen is produced by the green plants and certain
micro-organisms and is used by animals and most other micro-organisms.
– An example of a micro-organism that produces oxygen is cyanobacteria. They are found in oceans, rivers, bare rocks, and soil. “Blue-green algae”
• Water is necessary for all life.• Nutrients often enter the food chain with plants and
are very important for plant and animal growth.• Light is required for photosynthesis, which is the
process in plants that converts and stores the Sun’s energy into starches and sugars.
• Soil not only contains water and nutrientsbut also is home to many plants and animals.
Earthworms in soil
– A species is a group of closely related organisms that can reproduce with each other.
– A population refers to all of the members of a certain species within an ecosystem.
– A community is all the populations of the different species that interact within an ecosystem.
• Symbiotic relationships are the interactions between members of two different species that live together in a close association. – Commensalism – one species benefits, one is not
affected• Example: the barnacles on a whale
– Mutualism – both species benefit• Example: a bee gathering nectar from a flower
– Parasitism – one species benefits, the other is harmed
• Example: hookworm living in dogs
Mutualism Video
COMMENSALISM(Biological hitch-hiking)
The Imperial shrimp hitches a rideon a large sea cucumber. It ridesalong through areas of potential food, at no cost to the other organism.
Anyone home?The pearlfish is a small fish (5-10cm) that livesinside a seacumber in the day and at night, exits through the anus of the seacumber to feed.
MUTUALISM
• Leaf Cutter AntsThese ants cultivate (grow) a
fungus. They feed the
fungus and the fungus
serves as their food!
Cut the leaf..
Chew into a pulp
Store the pulp with ant feces
and fungus spores
Fungus begins to grow...
Teachers' Domain: Ancient Farmers of the Amazon
MUTUALISM
LICHEN = algae + fungus
The algae provides food
(glucose) for the fungus through photosynthesis.
PARASITISM
HOOK WORMS
The common way for hook worms to enter is through the skin (walking barefoot)...
A parasitic worm that lives inside the intestines of its host (mammal). These worms such blood
from the host’s intestinal walls ...this leads to anemia (iron
deficiency).
MOUTH
PARASITISM
• The Pine Beetle
The pine beetle has infested lodgepole pine trees in BC’s Central Interior.
Burrows in the tree, feeds on trees phloem (nutrients) and lays its
eggs.
The Pine Beetle’s Legacy....• In B.C., the provincial government estimates the
beetle's spread will have economic implications for 30 communities and will impact 25,000 families whose livelihood depends on the pulp and paper industry.
• The environment is also affected: trees normally capture CO2 (greenhouse gas) – but the death of more trees has instead released carbon into the atmosphere, according to a study published in April 2008 in the journal Nature.
A niche refers to the role an organism has within an ecosystem, physically, chemically and biologically.– Within the niche, an organism interacts with other
individuals of the same species or with individuals of other species
Competition is a harmful interaction that occurs when a resource is needed by two or more individuals.– Competition usually means resources are limited.– This limits the size and health of that individual
and perhaps that population.– Resources include food, water, and mates.
Predation is the relationship between predators “the eaters” and their prey “the eaten”.– Predators have adaptations to help them catch their
prey.– Prey have adaptations to help avoid predators.
• Examples of adaptations include spines and shells, camouflage and mimicry.
– The numbers of predators and prey influence each other.
Biodiversity refers to the variety and number of different individuals and species in an ecosystem.– Healthy ecosystems generally have high biodiversity.– Most biodiversity losses occur from the loss of habitat.
• Humans often have a negative impact on biodiversity.
– Many efforts are now made to lessen this impact in order to maintain biodiversity.• Ecological management programs try to balance human progress with maintaining
biodiversity.