Ecology Unit
A: organization of the Environment
B: Interactions in the Environment
C: Humans and the Environment
Vocabulary:
- Ecology- the branch of biology that deals with the interactions between organisms , and the relationships between the organisms and the environment.
2. Population- members of the same species living in a given area.
3. Community- includes all populations in a given area.
4. Ecosystem- all living things and the physical environment that they live in.
5. Biosphere- the portion of the Earth where life exists.
Requirements for a Stable Ecosystem:
- A constant supply of energy (SUN).
- Living organisms that can turn energy from the sun into organic compounds.
- Material must be recycled between organisms and the environment.
(Ex.- an aquarium is a stable, balanced ecosystem.)
Abiotic Factors:
- The non-living parts of the environment.
- Abiotic factors are:
- Air
- Water
- Soil
- Light (Sun)
- Temperature
- Minerals
Biotic Factors:
- The living things that directly or indirectly affect the ecosystem.
- Examples of Biotic Factors are:
- Producers- organisms that make their own food.
- Consumers- organisms that get their food from other sources.
- Decomposers- break down, and recycle, dead and decaying organisms.
Habitats and Niches:
- A habitat is the place in and ecosystem where an organism lives.
- A Niche is the role or job an organism has in an ecosystem.
Biodiversity:
Biodiversity is the diversity of species on the Planet as a result of the evolutionary process.
- Biodiversity increases the chance thatat least some species will survive in the face of large environmental changes.
- Biodiversity also increases the stability of an ecosystem and guarantees the availability of a variety of genes (large gene pool).
Interactions in the Environment:
- Food relationships involve interacting organisms.
- Organisms are either Autotrophs (organisms that make their own food- plants) or Heterotrophs (organisms that get their food from other sources).
- There are 3 types of Heterotrophs:
- Herbivore- eat plants
- Carnivore- eat meat
- Omnivore- eat plants and meat
- Carnivores can be further divided into 3 groups:
- Predators- carnivores that kill and consume their prey.
- Prey- the animals that are killed and eaten.
- Scavengers- eat the dead animals they find that are left over from the predators.
Symbiotic Relationships:
Symbiosis involves organisms of different species living together in close association with at least one of the organisms benefiting.
- Mutualism- both organisms benefit
- Commensalism- one organism benefits, the other is not harmed.
- Parasitism- one organism benefits (parasite), the other organism is harmed (host).
Food Chains:
Producer Primary Consumer Secondary Consumer
**Decomposers are found at every level of a food chain.
Food Webs:
A food web is made up of many interconnecting food chains.
Energy Pyramid:
- The Sun is the primary source of energy in an ecosystem.
- Energy is lost at each level on the energy pyramid.
- The greatest amount of energy is found at the producer level (bottom).
- The higher up in the pyramid the less energy.
Material Cycles:
Materials must be recycled between the living and the non-living environment.
There are 3 Material Cycles:
- Oxygen-Carbon Dioxide Cycle- (photosynthesis, cellular respiration)
- Nitrogen Cycle- dead and decaying organisms, nitrogenous wastes are converted.
- Water Cycle- evaporation, condensation, and precipitation.
Competition:
- Competition occurs when there is a struggle for the same limited resources.
- Competition may eventually cause one species to become extinct.
- Competition usually establishes one species per niche in a community.
Humans and the Environment:
- Humans differ from all other kinds of organisms in their ability to change the environment.
- Human activities upset various natural systems and have negative effects on the biotic and abiotic environment.
- Some changes in the environment can be repaired, some can not.
- In order for humans to survive as a species they must interact with many different forms of life, as well as, the non-living parts of the environment.
- The abiotic environment provides us with essential components upon which our survival depends.
- Acid Rain
- Greenhouse Effect
- Air Pollution
- Water Pollution
- Global Warming
These are just some examples of negative effects that mankind has had on the environment. These changes are caused by advances in technology.
Environmental Pollution:
- A pollutant is something that is put into the air, water, or soil that makes it dirty and unfit for living things.
- Pollutants are toxic (poisonous).
- Pollutants are by products of technology.
Negative Human Activities:
- Over-hunting
- Importing of organisms
- Exploitation
- Poor land management
- Deforestation
- Improper waste disposal (biodegradable)
- Use of biocides (pesticides, herbicides)
- Poaching
Conservation of Natural Resources:
- Conservation involves the protectionand wise use of our natural resources.
- Natural resources include the basic things in the natural world (soil, air, water, energy, wildlife, and open space).
- Renewable resources are able to be reused or replaced.
- Nonrenewable resources cannot be replaced.
- Recycling resources that are nonrenewable is recommended to conserve them.
- Erosion causes much soil to be lost because it is worn away by wind and water.
- Wildlife preservation is efforts to help endangered species and to protect other forms of wildlife.
- Laws to protect wildlife continue to be passed to help protect wildlife in danger of becoming extinct.