Aquatic habitats , Aquatic Ecosytems and Aquaculture Systems.-Introduction

1. Aquaculture

2. What we will cover
Theory
 Fresh Water Aquatic Habitats
 Aquatic Food Web
 Aquaculture Design
 Focus on Ponds
Practice
 Tyre Pond building after lunch

3. Rivers- Rain Fed
Head Waters-Upper Reaches Middle Reaches-Un spoilt Lowland Rivers
Spring-Fed Rivers
Lake Fed Rivers
Short Mountain Rivers
Estuaries

4. Brackish Still Water
Dune Slack
Saltpans
Brackish Lagoons and Pools

5. Upland Still Waters
Acid, Peat-Bog Pools Tarns
Glacial, Linear Valley Lakes

6. Lowland Still Waters
Fens
Meres
Ponds

7. What determines The Plant and Animal
Biota ?-
•Nutrient Content
•Depth and light penetration
•Acidity

8. What determines The Plant and Animal
Biota ?-Nutrient Content
The level of nutrients in the water underpins the existence of all
life, plant and animal
The nutrient content is affected by
 The geology of the catchment.
 The topography of the catchment.
 Intensiveness of agriculture in the surrounding area
 Size of surrounding human population (sewage)

9. Nutrients
Nutrients and Light = Phytoplankton
Algae-Diatoms-CyanoBacteria

10. Oligotrophic Waters
Glacial, Linear Valley Lakes
Tarns

11. Eutrophic Waters
Meres
Fens
Ponds

12. What determines The Plant and Animal
Biota ?-Depth and light penetration
 A high density of phytoplankton quickly absorbs the light and reduces the
depth at which the light can penetrate to approx 2m ,below this point nothing
can grow and animals cannot live.

13. What determines The Plant and Animal
Biota ?- Acidity
 Some species only live in PH 4-6 and some species only exist in slightly alkaline
waters pH >7.

14. An Optimum Aquatic Habitat
 A good supply of Nutrients supporting a high diversity of Plant and Animal life
 A balanced level of phytoplankton (PRIMARY PRODUCERS) so that light can penetrate
through the water
 A water body deep enough for plants to grow on the floor utilizing the filtered light
We can easily design this optimum Habitat.

15. Chinampas

16. Aquaponics

17. Ponds

18. Niche habitats for Aquatic plants

19. Emergents
Phragmites australis –
Common Reed
Uses
 Edible shoots, roots
 Insulation
 Fast growing biomass
 Basketry
 Tolerant of Wind

20. Deep Marginal
Nymphaea alba-White Water Lilly
Uses
 Edible roots and seeds
 Medicinal
 Shade

21. Oxygenators
Myriophyllum sp.-Water-mifoil
USES
 Forage for Fish
 Providing oxygen
 Edible roots

22. Floaters
Lemna minor- Duckweed
USES
 Forage for Fish
 Shade the water
 Edible –great for Chickens
 The dried plant repels mosquitoes
 Medicinal properties

23. Common Carp - Cyprinus carpio
Uses
 High Protein food
 Tolerance of a lack of oxygen
 Rapid growth
 Easy to feed
Info
•Common carps feed on small plants and
zooplankton, molluscs, detritus and dead
plants.
•The deep water is needed for winter
hibernation
•Logs and rocks with cavities for young fish
to shelter

24. Toads and Frogs
Uses
 Frogs and Toads will keep pest populations low
 A single adult toad can eat as many as 10,000 insects per summer.
Including Mosquitoes Edible Frog
 Frogs legs , taste a bit like chicken apparently :- Rana esculenta Rana esculenta
 Water quality control :they need clean water ,if you have them around
you can be assured your water is clean. If they start growing extra legs
be concerned.
.
Position
•The ideal pond for frogs and toads includes plenty of shallows for toads
to rest and breed.
•A deep area of at least 1.3 meters for overwintering frogs, and plenty of
vegetation around the edges to hide out in.
•Provide shallow, not steep, edges so frogs and toads can easily climb in
and out, or add a couple logs partly in and partly out of the water.
• Both frogs and toads will also really appreciate some rocks around the
edges for sunning themselves

25. Edge

26. Paulownia Garden Pond Design