ABBOTTSCOLLEGE

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ROLE OF INVERTEBRATES IN AGRICULTURE

ROLES OF THE INVERTEBRATES2

Pollination

Decomposition

Soil aeration

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POLLINATION

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Is the transfer of ripe pollen containing the male gametes from the anthers to the stigma to allow for fertilization

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IMPORTANCE OF POLLINATION4

Without pollinators:

Natural ecosystems would collapse

Agricultural production would be badly

affected and humans would be short of food

DEFINITIONS5

Pollinator = animal that moves the

pollen

Polleniser = the plant from which

the pollinators get their pollen

BEST INSECT POLLINATORS6

Butterflies Moths Ants Flies Beetles Bees

BEES7

Most of their life is spent collecting

pollen

Honey bee is the most commonly used agricultural

pollinator

CROPS POLLINATED BY INSECTS8

Fruit crops Vegetables Oilseed crops Nuts Coffee and

cocoa

PROBLEMS9

Bee populations are declining Fields/orchards and monocultures have led to

crops needing managed pollination Pollination management involves agricultural

practices that ensure the pollination of a crop so that the yield and quality of the crop is improved

Often involves commercial beekeepers becoming pollination contractors and transporting the bees to areas where they are needed

MONOCULTURE10

Monoculture is the agricultural practice of producing or growing a single crop or plant species over a wide area and for a large number of consecutive years. It is widely used in modern industrial agriculture and its implementation has allowed for large harvests from minimal labour.

DEFINITION

DECOMPOSITION11

Is a biological process that includes the physical and

chemical breakdown of complex organic molecules of dead

material into simpler organic and inorganic molecules

It is brought about by invertebrates and micro-

organisms

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INVERTEBRATES12

Beetles, slugs and worms feed on organic material, breaking it down

They break down plant litter (dead roots, leaves and grasses) = detritus

A complex stable organic material called humus is formed

Which improves the texture of soil and adds nutrients to it

MICRO-ORGANISMS13

Complete the breakdown process of organic matter

Nitrogen, phosphorus and sulphur are released into the soil

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SOIL AERATION15

Earthworms feed on detritus which they drag down into their burrows

Burrowing improves soil drainage by

creating passageways for air and water

Worms excrete casts

Worms work as pistons forcing air through the tunnels and aerate the

soil

Tunnels also allow roots to penetrate into

the soil

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  Vermicast, also called worm castings, worm humus or worm manure, is the end-product of the breakdown oforganic matter by an earthworm

DEFINITION

TO DO 17

LEARNING ACTIVITY 9

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POLLINATORS

TO DO18

LEARNING ACTIVITY 11

PAGES 90 – 92

SHORT QUESTIONS

THE END