Choose 3 different biome types. Give a description of each. Warm Up Choose 3 different biome types. Give a description of each.
Ecology
What is Ecology? Ecology is the study of interactions among organisms and their environments, or surroundings also includes the study of human interactions and the impact of human activities on the environment
The Biosphere The combined portion of the planet where life exists
Levels of Organization within the Biosphere Species- group of organisms so similar they can interbreed and produce fertile offspring Population- group of organisms of the same species living in the same area Community- collection of all species populations living in the same area Ecosystem- living community + nonliving physical environment Abiotic- nonliving factors Climate, sunlight, soil composition, nutrients ect… Biotic- living organisms community Biome- group of similar ecosystems with similar climate and similar communities Usually cover a large geographic area
Energy with Ecosystems Producers (autotrophs)- organisms capable of making their own energy supply Plants on land and algae in water (photosynthesis) Consumers (heterotrophs)- organisms that rely on other organisms for food supply (must consume other organisms to obtain energy supplies Herbivores, carnivores, omnivores, etc.… Primary, secondary, tertiary Decomposers- obtain energy by breaking down organic matter Bacteria & Fungi Very important- return nutrients to abiotic environment (soil)
Relative Importance Which class of organisms do you feel are most important and why? Producers- most vital (important) make energy for themselves all other organisms in their ecosystems. WITHOUT PRODUCERS there is NO OTHER LIFE! Decomposers- very important because they break down organic matter Return nutrients to soil/abiotic environment Consumers- complete the “balance of life” yet are least important
The Food Chain Series of steps that show feeding relationships and flow of energy through an ecosystem Each STEP IN FOOD CHAIN = TROPHIC LEVEL Starts with producer Convert energy from sunlight
Food Webs Show all the feeding relationships or interconnected food chains within an ecosystem
Flow of Energy Through an Ecosystem Energy Flows Through an ecosystem in ONE DIRECTION. It is not recycled! Organisms use approximately 90% of the energy they take in for metabolic activity (life processes) Most of this energy is lost to the environment as heat. Only about 10% of the energy that an organism takes in is stored in its structures and available for organisms at the next trophic level (step of the food chain) This relationship can be shown in an energy pyramid
The ENERGY Pyramid
Biomes of the World
The Niche An organism’s “role” within the ecosystem Feeding Relationships Where does it belong in food chain Physical requirements (temperature, shelter, etc…) Other relationships with other species
Community Interactions Competition- organisms of the same or different species trying to use the same resource at the same time Water, nutrients, mates, space Predation-one organism captures and feeds upon another organism Ex: Deer and wolf Predator-Wolf Prey-Deer
Community Interactions Symbiosis-when two organisms live close to one another and have some sort of Relationship Mutualism- a relationship in which both species benefit Ex: Oxpecker and cattle Commensalism- a relationship in which one species benefits and the other is neither helped not harmed Ex: Tree and bird Parasitism- a relationship in which one species benefits and the species is harmed Parasite vs Host Ex: Tapeworm (parasite) and Animals (Host)
Ecological Succession Ecological Succession- changes in a community after human or natural disturbances
Primary Succession Primary succession- no soil present Follows volcanic lava flows or eruptions Pioneer species- 1st species to populate the area Lichens, bacteria Other species follow as rock is weathered to create soil that is suitable Lichens grasses small shrubs trees This process is SLOW Eventually Reaches Climax Community Climax Community- steady community with lots of diversity and many community interactions
Secondary Succession Secondary Succession- Soil is already present Follows Forest Fires, Floods, Changes in Abiotic Environment, Human Disturbances etc.. Occurs much, much faster than primary succession Soil is already present
Limiting Factors A limiting factor is an abiotic or biotic factor that restricts the number of individuals in a population.
Limiting Factors Limiting factors can include: Competitors Disease and parasites Weather Fires Available habitat Predators
Population Growth 4 Factors that influence the growth of a population Immigration- individuals moving Into a population Emigration- individuals leaving or Exiting the population Birth Rate- Individuals being born per year Death Rate- individuals dying per year
Types of Population Growth Exponential Growth Continuous growth Must have unlimited resources and no limiting factors restricting a populations size/growth -not usually realistic in nature
Types of Population Growth Logistic Growth begins w/ rapid grow exponential phase Carrying Capacity- max # of individuals that ecosystem support growth rate slows as population size nears carrying capacity. WHY? Limiting Factors- limit pop. growth predation, competition, parasitism & disease Natural disasters, unusual weather and/or climate change, and human activity
Logistic Growth (cont.) Slight fluctuation near carrying capacity is normal Population could “crash” and reenter exponential phase
Biodiversity All the different species living on Earth Human activity has significantly lowered the amount of biodiversity on Earth. Are we currently causing a mass extinction? Extinction is a natural process but… It is estimated that human activity has increased the rate of extinction by 1,000 to 10,000 times the natural rate 30-50% of all species will be extinct by mid century (2050)
Who Cares? Human survival is tied to biodiversity Humans are dependent upon living things for: Natural resources Food and goods Pharmaceuticals (medicines)
Human Actions Habitat Destruction/Alteration- This is the leading cause of extinction. Urban development Industrial development Dams/Alteration of Aquatic Environments Agricultural Development Deforestation Habitat Fragmentation- splitting of ecosystems into pieces (islands) many organisms such as GRIZZLIES need a large area to survive. Fragmentation can equal extinction
Overfishing/Overhunting/Poaching
INVASIVE (nonnative) SPECIES Introduction of Invasive (nonnative) species has a negative impact on ecosystems Invasive species can outcompete native species and disrupt balance or relationships within a natural ecosystem
Pollution Acid Rain Toxic Waste Chemicals within smog combine with water from rain to form nitric and sulfuric acid Changes acidity of marine systems and terrestial systems Toxic Waste Biological Magnification- build up of toxins as they pass through food chain Some toxins do not degrade These toxins reach lethal level as they reach upper levels of a food chain Example- DDT
OZONE DEPLETION CFC’s and other Air Pollutants destroy the ozone layer Ozone (O3) is in the upper layer of the atmosphere and deflect much solar and UV radiation CANCER KILLS ALSO Contributes to global warming
GLOBAL WARMING Burning of Fossil Fuel INCREASES CO2 levels in the atmosphere CO2 is a greenhouse gas and traps heat Excess CO2 is causing global climate change is taking place
Conservation Efforts Today, focus is on saving entire ecosystems in addition to single species Ecological Reserves National Parks Ect… Doing so preserves relationships in nature and provides an increased chance of saving many species.
Write a story of ecological succession Write a story of ecological succession. Be sure to include whether its primary or secondary succession, what the cause is, and what organisms are arising.