Ch 2: Ecosystems and Ecology

Ecological footprint

are quantitative models which are usually measured for a given area and time.

Respiration

________ is the conversion of organic matter into carbon dioxide and water in all living organisations, releasing energy.

Ecosystem

________: is a community and the physical environment it interact with.

Exponential

________ or geometric growth: if no limiting factors are affecting or slowing down growth.

Photosynthesis

________: the process by which green plants make their food from water and carbon dioxide using energy from sunlight.

Commensalism

________: when one partner is helped and another is significantly harmed.

Ecology

________: the study of how organisms interact with the environment.

Mutualism

________: relation between two species where everyone benefits and no one suffers.

Autotrophs

________: make their own food from carbon dioxide and water using energy from sunlight.

Predation

________: when one animal (predator), eats another animal (prey)

Habitat

________: the environment in which a species normally lives.

Migration

________: immigration (moving into the area), emigration (moving out of the area)

Parasitism

________: relationship between two species in which one species lives in or on another (host), gaining food from it.

Chemosynthetic organism

________: make their own food from simple compounds.

Trophic level

A(n) ________ is the position that an organism occupies in a food chain, or a group of organisms in a community that occupy the same position in food chains.

Population

________: a group of organisms of the same species living in the same area at the same time, which are capable of interbreeding.

Community

________ is a group of populations living and interacting with each other in a common habitat (same place)

Consumers

________: feed on other consumers to get energy.

niche

A(n) ________ describes the particular set of abiotic and biotic conditions and resources to which an organism or population responds.

food chain

A(n) ________ is the flow of energy from one organism to another.

Herbivory

________: a herbivore animal eating a green plant some plants may have defence mechanisms.

Intraspecific competition

________: between members of the same species.

Population dynamic

________: the study of the factors that cause changes to population sizes.

Compensation point

________: point where a plant is neither adding biomass nor using it to stay alive.

abiotic factors

________: non- living physical factors that influence the organisms and ecosystems.

→ realised niche

describes the actual conditions and resources in which a species exists due to biotic interactions

Limiting factors

factors which slow down growth of a population as it reaches it carrying capacity

Population dynamic

the study of the factors that cause changes to population sizes

Intraspecific competition

between members of the same species

Interspecific competition

individuals of different species could be competing for the same resource

The principle of competitive exclusion

states that two species competing for the same resources cannot coexist

Predation

when one animal (predator), eats another animal (prey)

Herbivory

a herbivore animal eating a green plant some plants may have defence mechanisms

Parasitism

relationship between two species in which one species lives in or on another (host), gaining food from it

Mutualism

relation between two species where everyone benefits and no one suffers

Commensalism

when one partner is helped and another is significantly harmed

Exponential or geometric growth

if no limiting factors are affecting or slowing down growth

S shaped growth

starts with exponential growth, no limiting factors affect the growth

J shaped growth

population grows exponentially at first then collapses → called diebacks

Compensation point

point where a plant is neither adding biomass nor using it to stay alive

Chemosynthetic organism

make their own food from simple compounds

Ecological footprint

are quantitative models which are usually measured for a given area and time

Pyramid of productivity

shows the rate of flow of energy or biomass through each trophic level

**Productivity**

conversion of energy into biomass over a given period of time. It is the rate of growth or biomass in plants and animals

**Gross**

total amount of something made as a result of an activity

**Net**

amount left after deductions are made; what you have left, always lower than the gross amount

**Gross productivity**

total gain in energy or biomass of an organism before any reductions

**Net productivity**

gain in energy or biomass that remains after deductions due to respiration

**Gross primary productivity**

total gain in energy or biomass by green plants. It's the energy converted from light to chemical energy by photosynthesis in green plants

**Net primary productivity**

total gain in energy or biomass by green plants after allowing for losses to respiration.

**Biogeochemical cycles**

the natural pathways by which essential elements of living matter are circulated

**nitrification**

nitrifying bacteria in the soil which are able to convert ammonium to nitrates

**denitrification**

denitrifying bacteria in waterlogged and anaerobic conditions

**Energy budget**

can measure the quantities of energy entering and leaving the animal or population

**Maximum sustainable yield**

largest crop or catch that can be taken from the stock of a species without depleting the stock

**Biome**

is a collection of ecosystems sharing similar climatic conditions

**Biosphere**

part of the earth inhabited by organisms

**Zonation**

change in community and ecosystem aking and environmental gradient due to changes in altitude, latitude, tidal level or distance from shore/coverage by water

**Primary succession**

process of creating life in an area where no life previously existed

**Secondary succession**

when an established community is suddenly destroyed, an abridged version of succession starts

**K - strategies**

long life, slower growth, late maturity. Fewer large offspring, predator, high trophic level

**R-strategist**

short life, rapid growth, early maturity, prey, lower trophic level