Living world 1

abiotic

non-living things, ex = soil, rocks, water, sunlight

biotic

living things, ex = plants, animals, bacteria

biodiversity

variety of life in an ecosystem

biome

large areas on the earths surface with fauna and flora adapting to their environment, ex = tropical rainforests

biomass

renewable organic materials that comes from living or dead animals/organisms, such as wood, agricultural crops or wastes. can be used to generate electricity.

consumer

eats herbivores and/or plant matters

decomposer

organisms such as bacterium/fungus, that break down dead tissue, which is recycled to the environment.

ecosystem

natural system that compromises a community of plants and animals that interact with each other and their physical environment.

food chain

connections between different organisms (plants and animals) that rely upon one another as their source of food

food web

complex hierarchy of plants and animals relying on each other for food

nutrient cycling

set of processes whereby organisms extract minerals necessary for growth from soil or water, before passing then on through the food chain - and back to the soil and water.

producer

organism/plant that is able to absorb energy from the sun through photosynthesis

An ecosystem

important inter-relationships of biotic and abiotic components.

these interrelationships consist of =

- physical linkages between different parts of the ecosystem (ex = animal eating plants)

- chemical linkages (ex = mild acids in rain water speed up decay of dead leaves)

ecosystems rely on constant inputs such as

sunlight and rain from the atmosphere.

rainwater leaves the ecosystem when it evaporates or runs off into a river

Types of biomes

temperate boreal forest, temperate deciduous forest, artic & alpine tundra, grassland, tropical rainforest, desert, chaparral, tropical savannah

temperate boreal forest, 'taiga'

A northern coniferous (evergreen) forest. Cold woodland found North of deciduous forests. Largest biome covers 17% of earths land area.

Found in Canada, Europe, Asia and US

Temperate deciduous forest

Few extremes of climate, found in eastern half of North America, West of Europe and East Asia.

Has 4 distinct seasons (summer, winter, spring, autumn)

Winter = leaves fall off trees.

Autumn = leaves change colour.

Artic & alpine tundra

Covers 1/5 of earth. Little precipitation, short growing season and poor nutrients. Below freezing at night year round.

Grassland

Large biome with rolling terrains or grasses, flowers & herbs. Average annual precipitation is great enough to support grasses, in some areas a few trees. Precipitation is so unpredictable that drought & fire prevent large forests from growing.

Tropical rainforest

Very hot and wet biome located on/around the equator. Greatest biodiversity (no. of plants and animals) found anywhere on earth)

Desert

Very hot and very dry. Very little grows - only very hardy plants such as cactus can survive droughts.

Chaparral

Found in small areas of continents. West of US, West of South America, South Africa, West of Australia, coastal areas of Mediterranean.

Has flat plains, rocky hills and mountain slopes. Its very hot and dry. Winter is mild 10C, Summer is hot and dry at 40C that fires & droughts are common.

Tropical savannah

dry and hot, composed of mainly grassland and scattered shrubs and isolated trees, which can be found between a tropical rainforest and desert biome in Africa, Arabia and Australia.

Local factors affecting ecosystem distribution

Altitude, Mountain ranges, Ocean currents, Latitude

Altitude

100m increase in altitude (m above sea level = 1/2 C drop in temp

Mountain ranges

force moist air from oceans to rise, cool and condense, forming rain clouds - it rains on the ocean side of the mountain - leaving the other side dry, called rain shadow

Ocean currents

gulf stream keeps our west coast fairly mild even though we are out 50 degrees latitude.

Latitude

Global atmospheric circulation of winds in similar in certain latitudes. At the equator air masses come together (converge) and rise (low pressure) causing clouds to form - therefore it rains alot. At a round 30C N/S of the equator, air is sinking, forming an area of high pressure - no rain and calm conditions - it's still really hot here as it causes to the tropics - where we find our deserts.

Global factors affecting biome distribution

- 60-90 degrees from equator N/S = Polar cell, high pressure; cool air sinks and no clouds are formed = no rainfall, tundra - cold and dry.

- 30-60 degrees from equator N/S = Ferrel cell, low pressure; warm air rises, cools and condenses to form clouds and rain, temperate deciduous/coniferous forest - mild and wet.

- 0-30 degrees from equator N/S = Hadley cell, high pressure; cooler air sinks and no clouds are formed, no rainfall, deserts - hot and dry.

- Equator = Low pressure; warn air rises, cools and condenses to form clouds and rain, tropical rainforests - hot and wet.

producers

green plant that use photosynthesis and take nutrients from the soil

Primary consumers

herbivores, plant eating animals

secondary consumers

carnivores, meat eating animals

tertiary consumers

top predators, animals that feed on herbivores and other carnivores

What happens to biomass up the food chain?

Decreases.

Not all of plants/animals are eaten by animals, ex = bones & roots.

Energy is lost at each level, hunters us alot of kinetic energy as chasing prey can be time consuming and exhausting. Energy constantly used up in respiration. Much of animals daily calorie intake is used simply to stay alive rather than build new biomass.

Nutrient cycling

Decomposers break down dead organic matter and return nutrients to the soil as humus. Decomposers can be insects, detritivores, bacteria

Examples of a small scale uk ecosystem

detritus -> midge larva -> great diving beetle -> fish -> heron

Factors that disturb an ecosystem balance

Extreme weather, climate change, deforestation, tourism, disease, hunting

Inputs and outputs to an ecosystem

plants and animals can migrate in and out of ecosystem bringing change.

Inputs = sunlight, rainwater.

outputs = water evaporating to the atmosphere

rewilding

restore to a natural state. reintroduce species to natural environment or one similar.

ecosystem restoration

assisting recovery of an ecosystem that has been degraded, damaged or destroyed by human interaction/ action