[permaculture] Water Hyacinth

Lawrence F. London, Jr. lfl at intrex.net
Sun Sep 15 21:49:18 EDT 2002

Claude Genest wrote:
> I think John Todd is experimenting with using wather hyancinth as a medium
> in whicg to grow mushrooms (?)

Just to show you how big they can get -
Water Hyacinths in a lake in China:
See also:

That is covered in this website for Gaviotas:

"The African lake districts have an abundance of the waterweed commonly
known as water hyacinth (Eichhornia crassipes). This aquatic weed
has become a serious problem because it grows very fast and in the
process chokes up waterways, blocks navigable waterways, reduces
fishing points, and in some cases blocks water pumps. In Zimbabwe,
Chivero Lake became choked to the extent that the water hyacinth
mat could support human weight (Machena, 1997). The adverse impact
of the excessive growth of the water hyacinth is being felt in the
economies of all lake districts of Africa including Zimbabwe, Malawi,
Zambia, Tanzania, Kenya, and Uganda.
However, water hyacinth has a unique capacity to absorb and concentrate
massive amounts of inorganic minerals dissolved in the water mass.
As a result of this special charactersistic, the biomass can serve
as a productive resource for mushroom cultivation.
A year later Professor George Chan and Professor Mshigeni visited
Malawi to discuss with scientists from Bunda College of Agriculture
of the University of Malawi. Mr. Pauli and Professor Chan later
visited Tanzania for the same purpose. Under the ZERI vision, the
great water hyacinth problem came to be seen as a great opportunity.
The Tanzanian Commission for Science and Technology and colleagues
at the University of Dar es Salaam, all support the vision of promoting
the harvesting and using of water hyacinth as an agro-fertilizer,
as a livestock feed supplement, as a substrate for raising mushrooms
and earthworms, and as a source of biogas energy. These uses provide
both an immediate and a long term solution to the problem.
Scientific research initiated by Margaret Tagwira for ZERI Foundation
demonstrated that dried water hyacinth is the best substrate for
farming mushrooms. This program directed by Prof. S. T. Chang, an
authority on the matter, confirmed that the water hyacinth is a
blessing in disguise. Sociological studies confirmed that nearly
all African cultures had mushrooms as a part of their diet. The
spent substrate after fungi harvesting is rich in protein from the
mycelia of the mushrooms and are excellent feed for earthworms,
which convert it all into humus and can be fed to chickens, ducks and pigs.

After only 30 days, the dried substrate from water hyacinth produced
a variety of mushrooms. Once harvested, it did not take more than
ten days to harvest a second and even a third flush. One hundred
kilograms of dried water hyacinth generates more than 100 kilograms
of mushrooms. The water hyacinth outperforms traditional substrate
materials such as sawdust. In addition, since the substrate of water
hyacinth is rich in minerals and nutrients, the oyster and straw
mushrooms cultivated ended up enriched with potassium, magnesium,
iodine and calcium, along with numerous other components that are
critical to a healthy food diet. Much of what was lost in the form
of washed away topsoil can be recovered in the mushroom. The water
hyacinth can also recover harmful metals such as cadmium and lead
and store them in their roots if these metals are found in the rivers
or lakes.
The residual substrate of water hyacinth after mushroom farming,
is a rich food-base for cattle. Since nearly all the lignocellulose
has been broken down by the enzymes of the mushroom, the rest of
the material can also be used to farm earthworms, which will convert
the material into a humus. The humus that is produced in the process
can then be reapplied to the soils, recovering and replenishing
some of the lost topsoil. The earthworms can be used as high protein
chicken feed.
The cycle of biomass around the water hyacinth also allows for
the production of biogas generated from the waste streams. This
biogas is needed to sterilise the substrate for the mushrooms. Cattle
and chickens produce a lot of manure, which can be channelled into
a digester. This eliminates the need to cut firewood. The advantage
is a system that generates both revenues and jobs and converts a
problem into an opportunity."

lfl at intrex.net

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