ECOLOGY!

What is Ecology? - study of the interactions among organisms and between organisms and their environment. Some Vocabulary Review!

What is Ecology BIOTIC FACTORS – all living things in an environment Ex: plants and animals ABIOTIC FACTORS – all the non living things (physical and chemical)

Vocabulary Smallest unit in Ecology…. Individual Organism – one organism in an ecosystem Population – group of individuals of the same species living in a particular area.

Ecology Community – two or more different populations living together Ecosystem – all abiotic and biotic factors in an area

Ecology Biosphere – the sum of all Earth’s ecosystems

Ecology Main ABIOTIC factors to know! Sunlight Water Temperature Soil Wind Severe disturbances

Different environments on Earth : CLIMATE What is climate? - usually look at the temperature and rainfall of a particular area - Different patterns due largely to the uneven heating of the Earth

Uneven heating patterns Because the earth is a sphere – the sun’s rays hit it at different angles causing the different climate zones

Wind and Rain patterns

Food Webs and Energy Review: –Autotrophs- producers –Heterotrophs- consumers and decomposers –Herbivores- primary consumers (eat plants) –Carnivores- secondary consumers (eat herbivores) –Decomposers- consume organic wastes and dead organisms.

Food Webs and Energy 10% rule- each level of the food pyramid receives 10% of the energy from the level below it. Hawk (8 kcal) Snakes (80 kcal) Herbivores (800 kcal) Grasses (8,000 kcal) Hawks need to eat a lot more to get the energy they need

Food Web and Energy Biomass- the total quantity of living matter at each trophic level. Just like available energy decreases, so does biomass at each level.

Relationships in Ecosystems Predation- one species (predator) consumes another (prey). Competition occurs when two species are consuming the same prey.

Relationships in Ecosystems Niche- particular combination of resources that a species is adapted to. Example: A niche is available in forests for an animal that can live in the treetops and eat fruit.

Relationships in Ecosystems Symbiosis- Relationships in which species live together –Mutualism- both species benefit –Parasitism- one organism gains at the expense of the other –Commensalism- one organism benefits and the other is unaffected

Limiting Factors Factors that limit productivity in an ecosystem –Supply of water for desert plants –Supply of light –Supply of iron for algae –Supply of nitrogen in the soil –Temperature

Limiting Factors Productivity and population size of other species –Population size of birds is limited by productivity of insects that they eat –Or by the availability of nesting sites

Population Dynamics Two types of population growth –Exponential- growth under ideal conditions. Will result in enormous numbers of individuals. –Logistic- At first grows normally but slows down as competition and other factors limit reproduction and survival.

Carrying capacity The largest population of a species that the environment can support. –Are not stable –Invention of fertilizers led to more crops which led to more humans. The increase in crops could support a higher carrying capacity for humans.