Hong Kong Student Science Project Competition 2007

Homemade EcosphereBy

Ho Fung College

Chan Hei Ting SHEERALo Tin Long KYAN

Lau Hiu Ching TRACY

Commercial

Our “ecosphere”

Why did we design an Ecosphere?

Glass/Plastic Bottle

Duckweeds (Producer)

Decayed leaf (Dead organic matter)Stream water

Snail (Consumer)

Shrimp (Consumer)

Algae (Producer)

Bacteria (Decomposer)

ECOSPHERE: Our Set Up

Algae & Duckweeds

Algae

Duckweeds

Algae

Shrimps & Snails

Shrimp

Shrimp

Large Stream Snail

Large Stream Snail

Semi-decayed leaf

Bacterial Culture

Collect solution from ecosphere Transfer solution to a beaker

Gently daub on agar plate Appearance of bacteria after incubation for 3 days

5 areas of investigation

•Population of consumers•Amount of duckweed•Air-to-water ratio •Size of Bottle•Light Intensity

Population of consumers

1. Effect of the population of the consumers in ecosphere

0%

20%

40%

60%

80%

100%

120%

1 shrimp + 0

snail

2 shrimp + 0

snail

3 shrimp + 0

snail

4 shrimp + 0

snail

% survive after1 week

Data 1

＊ The dead shrimps are removed

Population of consumers

Effect of the population of the consumers in ecosphere

0%

20%

40%

60%

80%

100%

120%

1 shrimp+ 0 snail

1 shrimp+ 2 snails

1 shrimp+ 4 snails

1 shrimp+ 6 snails

1 shrimp+ 8 snails

% survive after1 week

Data 2

＊ The dead shrimps are removed

1 Shrimp + 2 Snails / 1 shrimp + 0 Snail

Amount of duckweeds

0

5

10

15

20

50% coveredwater surface

100% coveredwater surface

200% coveredwater surface

Effect of the amount of duckweeds

1 shrimp + 2 SnailsData 3

>15 days

Duckweed (100% covering water surface)

Air-to-water ratio

0

5

10

15

Day

s of s

urvi

val

0.5:1.5 1:01:00 0.65:1.35 1.5:0.5

Effect of Ratio of air to water in ecosphere

1 shrimp + 2 Snails

Data 4

>14 Days

Air-to-water ratio=1:3

Size of Bottle

0

5

10

15

Day

s of s

urvi

val

2L 1.5L 0.75L

Size of bottle> 15 Days

1 shrimp + 2 Snails

Data 5

The bigger the bottle, the longer

the ecosphere survives.

Light intensity

0

5

10

15

Direct sunlight Diffused sunlight Dim light indoors

Light intensity

> 15 Days

1 shrimp + 2 Snails

Data 6

Diffused sunlight

ImprovementWhy do we add the land environment? To make it more close to the nature !!

NEW Set Up

• Glass bottle of 6 Liters • Land: water: air Ratio= 1:3:1• Inner container • Garden soil • Small plants • Small animals

Organisms

Water: duckweeds, algae, shrimps, pond snails

Land: snail, slug, earthworm,millipede

Main concepts

Interesting Video

References

www.eco-sphere.com/ www.abundantearth.com/store/ecosphere.htmlwww.en.wikipedia.org/wiki/Ecospherewww.watersavers.com/docs/otherwatersaver_ecos_ball.shtmlwww.ecospherics.net/pages/MosqEcoFun5.htmlwww.open2.net/diyscience/ecospherewww.trendhunter.com/trends/ecosphere-self-contained-ecosystems