Energy And Nutrient Transfer (BIOL2)

SUN

LIGHT ENERGY (photosynthesis - chemical energy)

TREE (producer)

CATERPILLAR (consumer - herbivore)

SMALL BIRD (consumer 2 - carnivore)

HAWK (consumer 3 - top carnivore)

(Direction of energy and nutrient flow going down the page)

1) Much of the light energy can't be used by the plant because-

• most doesn't hit the plants
• Some is reflected from the leaf's surface e.g waxy cuticle
• only part of the light is used/useful and can be absorbed by chlorophyll    
• right colour- red / wrong colour - green

2)Energy is lost from animals and plants

• Sun ----> 98% energy lost
• Producer ----> 90% energy lost
• Primary Consumer ----> 90% energy lost
• Secondary Consumer ----> 90% energy lost
• Teritary Consumer

• Not enough energy to sustain another level

Energy is lost by -

A)Respiration produces heat

B)Death and decomposistion (including urine and faeces) as the energy goes into decomposers, Bacteria and Funghi

C)Some parts of the body cant be digested e.g- callulose,bones,teeth

1) Respiration - all cells need energy to work, heat, repair

2)For Growth - when a plant grows, biomass increases

3) Transferred to decomposers ( funghi and bacteria)

4) For reproduction

A)Number

ALWAYS A PYRAMID

BIO - Living

MASS - weight in an area - quantity determined by number and size

No nutrients are ever lost from an environment (energy) they are changed from one form to another

Excretion (urine)                              The nutrients must be released to be used

Egestion (faeces)  ------>                        

Death                                             Cycling of nutrients to give a balance

• This is achieved by DECOMPOSERS = BACTERIA AND FUNGHI
• They use the nutrients for themselves - for respiration (energy) reproduction and growth

They are then available for other organisms

1) Digging/Ploughing/Draining - improve aeration --> denitrifying bacteria die - nitrifying bacteria increase

2)Fertiliser

a) Artficial eg nitrates

b) Natural -  maunure, compost (impoves texture of soil) --> help restart the nitrogen cylce (nitrifying bacteria increase)

1) Deforestation - removes tress - less photosynthesis - CO2 NOT REMOVED

2) Increased combustion for energy - CO2 is produced

Effects

• CO2 + Water(rain) = ACID RAIN - erosion of stone - plant leaves destroyed - lakes acidified
• Greenhouse effect - GLOBAL WARMING - climate change