Post on 11-Jan-2016
transcript
THE BIOSPHERE“LIFE BALL”
Unit 3
What is Ecology?
The Scientific study of the interaction among organisms and between organisms and their environment.Ernst Harckel coined the term ecology
based on the Greek word for house.Harckel saw the earth and its various
environments as “houses” with each of its organisms playing a role (interacting) to keep the “houses” going.
Houses….. Nature’s “houses” come in many sizes from single
cells to the entire planet. The largest of nature’s houses is called a
biosphere. Biosphere- the part of earth in which life exists
including land, water(11km), and air or atmosphere(8km).
Levels of Organization
Biosphere (largest)Biome-group of ecosystems that have the same
climate and dominant communities.○ Ecosystem-collection of all the organism that live in a
particular place, together with non-living things.Community-assemblage of different populations
that live together in a defined area.- Population-group of individuals of the same
species that live in the same area.- Individual (species)-a group of organisms so
similar that they can breed and produce fertile offspring. (smallest)
How do ecologists study the biosphere??
Three Ecological Methods of Study.Observing: What lives here? How many? Etc.Experimenting: Imitation of natural environmentsModeling: Create models using computer or mathematical
formulas
Energy Flow in the Biosphere Sunlight: The main source of energy for all
living things on earth. Producers: An organism that can capture
energy from the sun and use it to produce food (autotroph).Photosynthesis- uses light to make food
(Phototrophs)Chemosynthesis- uses inorganic molecules
(Chemotrophs) Consumers: An organism that relies on other
organisms for its energy (heterotroph).
Consumers Cont….
Types of HeterotrophsHerbivores- Eat only plants (ex. Cow).Carnivores- Eat only other animals (ex.Owl).Omnivores- Eat both plants and animals (ex.
Humans).Detritvores- Feed on detritus, dead or
decaying materials (snails, crabs).Decomposers- Breaks down dead organic
matter (bacteria). Sunlight Autotrophs (producers) Heterotrophs (consumers)
Energy continued…. Feeding Relationships: Energy flows
through an ecosystem in one direction from the sun or inorganic compounds to autotrophs and then to heterotrophs.Food Chain: Series of steps in an
ecosystem in which organisms transfer energy by eating and being eaten.
Food Web: Network of complex interactions formed by the feeding relationships among organisms in an ecosystem.○ Trophic Levels The steps in a food chain or
web.
Food Web Ex.
Ecological Pyramids A diagram that shows the relative
amounts of energy or matter within each trophic level in a food chain.Energy pyramid- shows relative amount of
energy available at each trophic level.Biomass pyramid-total amount of living
tissue within a trophic level.
Cycle of Matter
Recycling in the biosphere- Unlike the one-way flow of energy within a biosphere, matter is recycled. Water CycleNutrient Cycle (Biochemical cycles)
○ Carbon Cycle (key ingredient in living things)○ Nitrogen Cycle
Needed to make amino acids78% of the Earth’s air
○ Phosphorus CycleEssential for DNA and RNA
Water Cycle
Evaporation- Liquid Gas Transpiration- evaporation from the leaves of plants Precipitation- The release of condensed liquid from clouds Condensation- Gas Liquid Runoff- Precipitation runs along surface of ground until it enters a
river or stream. Seepage- Rain water seeps into the soil and becomes ground water.
Nutrient Cycle
Carbon Cycle Nitrogen Cycle
Four Types of Processes that Impact the Biosphere Biological-Take up carbon and release
oxygen (ex. photosynthesis & respiration) Geochemical-Erosion and volcanic activity
that release carbon dioxide. Mixed Biogeochemical- Decomposition of
dead organisms, underground pressure that leads to formation of coal.
Human Activities- Release CO2 into the air by cutting and burning forests, burning fossil fuels.
Nutrient Limitations
Primary ProductivityRate at which producers make organic matter.Controls the amount of nutrients available.
Limiting NutrientsScarce nutrients, limits organism’s growth.Farmers use fertilizer to try and fix this
problem.Can have sudden increase in limiting nutrients
usually in aquatic ecosystems due to runoff.○ Algae Bloom