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Water
"In an animal or a plant, 99 molecules in 100 are water... an organism is a pool in a stream of water along which metabolites and energy moves through ecosystems."
- W.V. MacFarlane
Design and land selection
All other factors (soil type, present uses, market potential, etc.) are secondary to water availability. With water we have the power to increase surface storage, reduce runoff, and decrease evaporation.
The techniques are:
Soil storage
Swales
Mulching
Small surface storages like dams and tanks
1. Soil Storage
Freshwater is mostly held in soils and plants, not in rivers, streams, etc. The amt. of soil water is 15 times the amount in channel storage in rivers.? (Nace in Chorley, 1969) Soil: largest storage system in the landscape if it is allowed to absorb it. Soil conditioning (passive building up of soil or conservation tillage) followed by tree planting, trace element addition, non-destructive agriculture, sparse grazing increases (up to 70-85%) the ability of soils to hold and infiltrate water. Areas of 85% run-off can be converted to zero overland flow with proper techniques. Soils contain many times the water of open storages/streams which increases cycling (via evaporation and transpiration.) SO soil treatments now need to proceed tree planting over many areas previously used by contemporary agriculture.
2. Swales
Level grooves to hold water momentarily to keep it form running away rapidly downhill. Water soaks into the ground, and eventually slowly charges up with water. Trees planted either side of swale will thrive. Swales stop water and infiltrate overland flow.
Village Homes, Davis, California - With 15" rainfall, recharged groundwater supplies to 17 feet in 4 years.
3. Mulch
Imitation of the forest floor. Reduces evaporation, prevents erosion, and builds up soils.
4. Small Surface Storages
Tanks, water catchment, small ponds in gardens, stock ponds, steep hillside path ends. Water storage should be roughly 15% of the land. Try to place water as high as possible. Make a few smaller dams rather then a big one to cut back evaporation.
Rain catchment: Sq. ft. x inches/rain/year = x (converted to gallons.)
Irrigation
Drip or trickle - Dusk or Night
Under canopy - Under Mulch (Reduces salt, increases efficiency)
Techniques:
In dry areas, long waterings are better (every 3-5 days rather then a little every day) to increase leaching in poor/arid soils, and to take water down farther to tree roots) Use a network of distribution like nets and pans, pipes, channels, buckets. Keep in mind energy sources: water at head (high), pressure with the pump (electric, fuel, wind, hand, etc.) Sprinklers are NOT efficient. Note driplines of trees, structures, etc.
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Aquaculture
Water ceases to be an erosive influence and becomes a productive medium for plant and animal cultures. Aquaculture and tropical rainforests are the 2 most productive systems in the world. Given the same inputs we can get 4-20 times the yield in an
aquaculture systems than from adjoining land. A pond polyculture can act as a mirror, a heat store, a run-off area, a cleanser of pollutants, a transport systems, a fire area, a recreation asset, an energy storage, or an irrigation accessory.
Limiting Factors
1. Energy accounting
Carnivorous fish are the most expensive to raise. However, in relation to other meat production, fish of any kind is the more efficient to produce.
Fish: 1.5-2.3 lb/food (high quality) to 1 lb fish flesh (1:1 or 2:1)
Poultry: 3.5 lb/food to l lb bird (4:1)
Beef, pork, lamb: double or triple feed cost of fish, need MUCH more energy to produce.
2. Oxygen level (above 5ppm)
3. Temperature (Site specific)
4. pH between 6-8
5. Nutrients Too much, low quality (anerobic.) Need herbivorous fish or shrimp.
Design Strategies
1. Take off a season to drain and lime pond periodically.
2. Keep one bank clear.
3. Fertilizing-pig, duck, bird manure (perches over water, animals at edge). Increases yield 2-10x. Yield of the species near the pond will double if the pond is fertilized such as melon, tomato, fuel forests.
4. Incorporate filter feeders for water quality: fertilizers evaporate quickly. Ex. Potash is gone in 12-14 hours. There are VERY quick cycles in pond: we need filter feeders to trap (store) nutrients.
Fish alone: 316.6kg yield of fish
Fish plus mussels: 464.4kg yield of fish.
5. Create shelters/refuges for fish, crabs, other creatures in the system.
6. Species selection
Bass (omnivours) 196kg/hectare/yr.
HOWEVER - Diversity of fish: Yield 40-200% by selecting many species (Research
this. Some species will eat others.)
7. Stocking. (Do not over or under stock.)
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