Ecology.txt

All the external factors that influence an organism

Ecology is the study of how living things relate to each other and to their environment

An ecosystem is a group of clearly distinguished organisms that interact with each other and their environment as a unit

A community is all of the organisms in an ecosystem

A population is all the members of the same species in an ecosystem

The biosphere is the part of the planet containing living organimss

A habitat is the particular place within the ecosystem where an organism lives

• Abiotic - non living factors
• Biotic - living factors
• Climatic - weather conditions over a long period of time
• Edaphic - factors referring to the soil

• Temperature of land and water
• pH
• Light intensity
• Water

• Plats - food and shelter
• Predators - reduce number of prey
• Prey
• Parasites
• Humans (pollution)

• Temperature
• Rainfall
• Wind

• Soil pH
• Available water
• Air and mineral content

• Light penetration
• Currents
• Wave action

Producers are organisms that carry out photosynthesis

Primary consumers feed on producers

Secondary consumers feed on primary consumers

A sequence of organisms in which each one is eaten by the next member in the chain

One where the initial plant is living

One where the chain begins with dead organic matter and animal waste (detritus)

2 or more interconnected food chains

Refers to position of an organism in a food chain

Size (e.g. Single rosé bush can support thousands of green flies) INVERTED

distorted when parasites

A niche is the functional role of an organism in an ecosystem

• 1. Respiration in plants, animals and microorganisms
• 2. Decay caused by microorganisms
• 3. Combustion ie. fossil fuels

Nitrogen gas must first be 'fixed' ie changed to a suitable form (ammonia in nitrate)

Protein, DNA and RNA manufacture

A conversion of gaseous nitrogen to a form that can be used by organisms

The conversion of ammonia to nitrites and then to nitrates

The conversion of nitrates into nitrogen gas

Pollution is any undesirable change to the environment

A condition where lakes become over enriched with nutrients, resulting from excess artificial fertilisers washed into rivers and lakes

Avoid spreading on wet, frozen, sloping land

Fossil fuels release acidic CO2 and SO2

• Erosion of limestone
• Lower soil pH
• Breathing problems

• Burn less fossil fuels
• Switch to clean energy

Conservation is the protection and wise management of natural resources and the environment

• Existing environments are maintained
• Endangered species are preserved for reproduction
• The balance of nature is maintained
• Pollution and it's effects are teduced

• Availability of suitable landfill sites
• Toxic or polluting content of fumes from incineration
• Decaying waste produces methane
• Harmful substances may leak into ground water supplies

Use microorganisms

Reduce reuse recycle

• Unpleasant odours
• Infestation of rats
• Maggots

• Animal feeds and oils
• Fish offal is converted to fish meal and this is sold as animal Feed
• Oil is extracted, refined, health food supplements

• 1. Completion
• 2. Predation
• 3. Parasitism
• 4. Symbiosis

• Food and shelter
• Safer in a group
• Availability of a mate for breeding purposes

When organisms of the same or different species "fight" for the necessary resources that are in short supply

Between members of the same speoes

Between members of different species

Light, water, minerals and space

Food, water, shelter, territory and mates

Involves an active physical confrontation between two organisms

Is when each organism tries to acquire as much of the resource as poddible

• Restricts population size
• Only successful competitors survive and reproduce
• A driving force behind ecolutoon

• Changing feeding habits
• Camouflage
• Producing protective costs
• Moving away from over populated areas

• Plants
• Produce large number of seeds
• Plants thrive even in poorer soil conditions

The act of some animals capturing and killing other animals for food

Animals that hunt, kill and eat other animals for food

• Stabilises the community
• Control the number of herbivores, prevent overgrazing
• Eliminate the less well adapted prey

• Keen senses and sharp teeth
• Catch easiest prey, old and sick
• Live and hunt in packs
• Migrate to where prey is plentiful
• Camouflage

• Hawks have good eyesight
• Cheetahs can run at 60km/hr

• Plants have thorns, spines or stings
• Nasty taste when eaten
• Are faster than their predators
• Safety in numbers
• Camouflage

One organism, the parasite, benefits from another, the host, and does harm to it

Where two organisms of different species have a close relationship where at least one of them benefits

1. The availablity an abundance of food

• 2. Concealment
• Less prey, hide better. Allows population to survive and increase

• 3.Movement of prey and predators
• When not enough food, prey will migrate
• Predator moves to area with more pret

• Immigration to new area
• Rise in birth rates

• Death
• Emigration

• 1. Famine
• 2. War
• 3. Disease
• 4. Contraception