Designing Ecological Habitats - Gaia Education

134 Designing ecological Habitats
gardens etc. as outlined above, HPC has developed ways of using domestic
waste-water from household use, which it demonstrates and trains to local
villagers. Normally, water is carried from taps or springs in containers and
used for cooking, dish washing and general household duties. Grey-water from
these uses is normally thrown away with little or no further use. By strategically
locating the hand and dish washing area close to a kitchen garden, or laying a
pipe that carries it there, this water also can be recycled for productive means.
Some washing is also done over compost heaps to provide moisture for faster
breakdown of biomass during the dry season. In this way, what was a limiting
factor of water has been linked to a waste product that had not been used.
Low-water use Rice Cultivation
There are many types of cultivation that can be used as part of water
conservation strategies. One of them, the System of Rice Intensification
(SRI) is a relatively new technique for rice cultivation. It involves four major
changes from conventional rice production:
1. The seedlings grown in the nursery beds are transplanted after just
8-12 days, or at the 2-leaf stage.
2. Seedlings are transplanted singly, not in a bunch.
3. Seedlings are transplanted at a wide spacing, from 25 to 50cm
apart.
4. Much less water is kept on the paddies, and the soil is allowed to
dry out (‘crack’) from time to time.
Paddy managed under SRI has shown good increases in yield. Double yields
are not difficult to achieve, and some farmers have achieved up to 4 times
their normal yield. The benefits are:
• rice production increased (up to 16T/Ha has been documented)
• less water needed (minimum around 15-25% of normal practice)
• less seed needed (about 12% of normal practice)
• no extra external inputs needed
• can use local/traditional seed
• more straw
• due to better soil and water management there is:
- less pests and disease
- better quality grain
- more fertile soil
SRI also has great potential to combine with other methods such as no-till
(see Fukuoka), mulching and green manures within the rice crop, as well as
intercropping with other crops.