Subject: duckweeds
----------forwarded message-------------
From: Susan Goldhor [70760.742@CompuServe.COM]
It is always difficult to say what the appropriate handling of a waste =
will be on someone else's facility. It may be that the most effective =
use of the pig manure on the SAC Farms in Western Samoa would be to =
treat digestion or partial digestion as an initial step, using a simple =
settling of the wastes in anaerobic pits or tanks. A simple system for =
this is described in a booklet entitled "Duckweed Aquaculture: A New =
Aquatic Farming System for Developing Countries" by Skillicorn, Spira & =
Journey, and published by the World Bank in 1993. I agree with George =
Chan that handling raw wastes is no fun, but they can be separated by =
settling with a minimum of handling. The liquid fraction can then run =
off and be used to grow duckweed, which is an interesting and unique =
crop for the developing world.
The family, Lemnaceae, includes Lemna, Spirodela, Wolffia and Wolfiella. =
Duckweeds grow naturally in most climatic zones. Although duckweed =
growing wild may contain only 15 to 25% protein (on a dry weight basis), =
duckweed cultivated on highly nutritious waters, such as sewage, can be =
as high as 35 or 45% protein. Similarly, fiber content goes down in =
high nutrient culture from 15 to 30% to 5 to 15%. Duckweed's essential =
amino acid composition resembles animal protein more closely than it =
does most plants, and it also contains high concentrations of beta =
carotene and xanthophyll. Yields are very high -- in an experimental =
culture situation in Bangladesh (grown on sewage), from 13 to 38 metric =
tons/hectare/year of dry matter were estimated to have been produced. I =
mention these characteristics because they are sufficiently unique that =
it may be worth the trouble to settle and separate wastes to grow such a =
potentially valuable crop, particularly for an organization such as the =
SAC Farms, which has expressed an interest in growing fish, since wet =
duckweed may be used very successfully as is, in carp polyculture. =
(Including wet duckweed grown on human sewage.) =20
There are also some interesting characteristics of duckweed which permit =
it to be grown rapidly on high nutrient sewage containing some level of =
toxins and heavy metals, and to be harvested as a safe feed; this is =
possible because of little uptake of these compounds during rapid =
growth; the final effluent, with most nutrients removed is then sent =
into a polishing tank where duckweed growing under low nutrient =
conditions takes up these more toxic compounds.
Lemna is well suited to growing on sewage and is being increasingly used =
for secondary and tertiary sewage treatment, both commercially in the US =
and in small, low tech systems suitable for many countries and climates. =
Although almost everyone's initial impression is similar to yours, =
which is that it is unsanitary and dangerous to grow a crop on sewage, =
the data do not seem to bear this out. Of course, certain practices =
must be followed to allow parasites to sediment and bacteria to die off. =
However, these practices are very simple, and long-term studies carried =
out in Peru showed no instances of human pathogens carried by human =
sewage-grown duckweed in four years of testing. =20
Whether duckweeds grown on human or swine sewage could be used as human =
food is a subject which I don't feel capable of addressing, and should =
be approached with caution! However, there are precedents for the safe =
use of such plants as fish or poultry feed.
I would suggest that any interested person obtain a copy of the World =
Bank booklet on Duckweed Aquaculture as a starting point. I am not an =
expert on duckweed, but have become very interested in its potential =
over the last year, and I believe that it has far more to offer than we =
are currently taking advantage of.
I hope that this has been helpful. Best wishes,
Susan Goldhor =20
----------forwarded message------------
From: Robert Faust [drfist@ilhawaii.net]
Since mushroom compost is already "compost" and one of the best if it is =
made right, it has no value for ruminants, or earthworms initially, =
because it has most of the soluble nutrients removed by the crop and it =
is then steamed before removal from the beds to prevent the spred of of =
lafrance and other mushroom diseases, so you have a practically sterile, =
dead, already composted material. Hence ageing is necessary to get, low =
molecular weight humic acids formed, this takes time. The value of humic =
acids is clear, the important ones are the low weight fulvic, which have =
so many effects. To understand the benefits of these things you need to =
understand what humic acids are about how they are formed. Mushroom =
compost is a good source but this takes time and there is no substitute =
for time when it comes to specific production of humic bio-polymers. =
Fungus product humic acids to protect themselves from toxic components =
of the substrate,once these are produced then greenplants can utilize =
the humic acids produced.
Robert H. Faust Ph.D. Agroecologist
Faust Bio-Agricultural Services, Inc.
P.O. Box 800, Honaunau, Hawaii 96726 U.S.A.
Voice 1-808-328-2083 FAX 1-808-328-9760
"To be economical and ecological, agriculture must be biological"
http://www.wp.com/bioag/
http://www.humic.com
Subject: [IBS-GEN] IBS using earthworms in the Philippines
Jim McNelly [compost@cloudnet.com] wrote:
>>>>>Dr. Edwards....best example of an integrated biosystem was of a =
site he visited in the Phillippines in the mid 1980s while researching =
the earthworm perionyx excavatus which is native, I believe, to the =
islands there. He visited a farm that was on a hill where discarded =
food products from a city were fed to pigs; the pig manure was washed =
downhill to earthworm beds after which the surplus worms were fed to =
geese that lived in a pond where the liquid run-off was captured that =
also fed water plants that fed ducks. The worm castings were harvested =
into intensive gardens and the final water was discharged into rice =
paddies that also grew carp.<<<<
very interesting.
This is just out of curiosity: Jim - you wrote - "the pig manure was =
washed downhill to earthworm beds" - Q; it does sound like a wet system =
for earthworm cultivation if you use the word "washed" ?? Please confirm =
! Is the liquid handled to separate the solids and the liquid run-off =
allowed to go into the pond for water plants ? or is this a "natural" =
process where the manure is flushed into an area where earthworms =
flourished because of to the accumulation of solids. Since we have a =
hill, the run-offs accumulate at a spot that turned into a pond for =
water plants. Or was it designed to operate this way!!.=20
I once saw solid pig manure piled in a row due to space limitation and =
housefly margots started to grow well to such a nuisance that the =
piggery had to recruit the help of ducks to keep the margot numbers =
down. This turned out to be so effective and the farmer was proud to =
talk about his production of duck eggs.=20
The pig-earthworm-geese-water plants-garden-rice-fish system looks like =
a complex system, esp. with the interesting input of food wastes. There =
is always the hygienic aspects that one must be careful in such types of =
practices esp. when no technology is used and where land space is =
limited so limiting the time needed to kill pathogens naturally. The =
introduction of anaerobic digestion can keep things under control and =
further the biogas produced can be used to cook food wastes; cooking =
food wastes helps to reduce diarrhoea occurrences in pigs.
regards, jacky
Subject: [IBS-GEN] Spent Mushroom substrate
Jim McNelly [compost@cloudnet.com] wrote:=20
>>>>Regarding spent mushroom compost as an earthworm feed, my experience =
based on working nine years at a mushroom farm in Colorado was that the =
mushrooms were direct competitors with the worms for nutrients and that =
the worms did not thrive in the compost or reproduce in any significant =
quantity in spent mushroom compost. Worms disrupted the culture =
necessary for mushroom cultivation when placed in the same beds. =
Redworms also require a high moisture content in their bedding that does =
not support commercial mushroom cultivation.
Other species of soil worms such as lumbricus terrestris, the common =
nightcrawler will come to the surface of their burrows and feed on land =
applied mushroom compost. I am certain that in a controlled regimin, =
that the population of this popular bait worm can be increased to =
harvestable levels. But I would look to other animals than the common =
redworms that are used in intensive vermiculture.
Earthworm castings have had excellent results, I am told, as a =
substitute for sphagnum peat moss as a casing media on the surface of =
mushroom compost during the cultivation period. Perhaps this is one way =
to harvest the benefit of the worm in an integrated system. In the =
potting soils I have marketed since 1974, I use both earthworm castings =
and mushroom compost in the media along with bark mulch, peat, and =
vermicultite.>>>>>
I think we have some mix-up here. There are 3 things involved in this =
discussion -
(a) "mushroom compost" i.e. compost that is prepared to serve as a =
substrate for mushroom (spawn) cultivation =20
(b) "spent mushroom substrate" i.e. after mushroom cultivation, the =
waste residues is called the spent mushroom substrate
(c) "spent mushroom compost" i.e. compost made from spent mushroom =
substrate.
In making the mushroom compost, we need to keep earthworms out. In using =
spent mushroom substrate for composting, yes we need the earthworms in.
Statements:
(a) with reference to vermiculture: "the worms did not thrive in the =
compost or reproduce in any significant quantity in spent mushroom =
compost" . Yes, I agree. To grow earthworms we need fresh food (note: =
for some materials a short decay period will make the food more =
digestable to erthworms). Spent mushroom compost is already a product =
and therefore should be used on growing plants and not for growing =
earthworms. I note Robert Faust's recommendations and importance to =
enhance humus production by longer composting time.
Q: Nick (and others), have you grown earthworms on spent mushroom =
substrate or do you know of any references ?
Q: Nick (and others), do you know of any work where spent mushroom =
substrate is used as livestock feeds ?
regards, jacky
Subject: Re: [IBS-GEN] growing termites on wastes
I like the idea of using termites to digest lignocellulosic wastes,might
make real sense for tropcial aquaculture to feed the larva to fish,higher
amino acids the fish need, actually I do this with plurotus sp. and other
whiterot fungi, and get good feed as well, but with termites less
processing may be neccessary resulting in cheaper feed from L/C wastes.
Here in Hawaii the trick is to build a house that will survive termites
before the mortage is paid off. Being an entomologist and pest control
advisor among other things, I build a termite proof house. So I respect the
power of termites, they own the forest in places like Belize. Here they can
eat your wooden chair from the inside and it will fall apart, so yes.
Robert H. Faust Ph.D. Agroecologist
Faust Bio-Agricultural Services, Inc.
P.O. Box 800, Honaunau, Hawaii 96726 U.S.A.
Voice 1-808-328-2083 FAX 1-808-328-9760
"To be economical and ecological, agriculture must be biological"
http://www.wp.com/bioag/
http://www.humic.com
Subject: [IBS-GEN] growing termites on wastes
note:=20
(a) in this message: "spent mushroom compost" has been replaced with =
"spent mushroom substrate".
in order to distinguish between "mushroom compost" that is used for =
mushroom cultivation and "spent mushroom substrate" which is the residue =
after mushroom cultivation.
=20
----------forwarded message--edited---
From: Tim Myles
Re: Possible use of termites on spent mushroom substrate or other =
agricultural byproducts.
Spent mushroom substrate is likely to be an excellent physical and =
nutritional medium for termites. Termites are the main group of =
invertebrate animals that digest low-nutrient, lignocellulosic, "brown" =
matter. We northern hemisphere biologists have a profound blind spot =
when in comes to appreciating the stupendous importance of termites in =
the carbon cycle. Termites are the major animal bioconverters of plant =
cell wall matter into animal biomass on this planet. I'll just repeat =
that: Termites are the major animal bioconverters of plant cell wall =
matter into animal biomass on this planet. In performing this they =
support a huge percentage of small vertebrate insectivore biodiversity.
One popular misconception about termites is that they eat only wood. =
This is true of only the most notorious pests. It is estimated that over =
50% of all termite species are humivorous. Entire subfamilies of the =
higher termite family Termitidae, such as the Apicotermitinae and =
Termitinae are humivourous. Many other termites feed on surface litter, =
dry leaves, grass, and even lichens. In arid areas, where animal dung =
rapidly becomes too dry for dung flies and dung beetles, termites are =
the major decomposers of herbivore dung. In fact, many of the most =
abundant termites in arid and semi-arid regions of the world are dung =
feeders. This is true in the American Southwest, where several species =
of Amitermes, Gnathamitermes, and even Reticulitermes are commonly found =
in dung. In fact, I am in the process of describing a new =
dung-specialist genus which is found in the American southwest and =
Northern Mexico.
Decompiculture, or the culturing of decomposer organisms, is the =
inevitable next step in mankind's utilization of natural resources and =
ecological integration in the biosphere. Large scale composting is the =
first evidence that we are waking up to this ecological imperative.
The most important candidate decomposer organisms are bacteria, =
actinomycetes, fungi, earthworms, termites, beetles and flies. Up until =
now, these organisms (decomposers) have not been seen as sources of =
production. Those of us who study these organisms tend to study the =
relatively few that are pests. The majority however are beneficial and =
essential cogs in the cycling of nutrients. Now that humankind has =
progressed to the point of having numerous large organic waste streams =
we must now develop intensive decomposition systems to match our =
intensive production systems.
"Termite ranching" or termiticulture inevitably will be much more =
important than vermiculture because termites are able to utilize lower =
nutrient substrates, wood and humus. Termiticulture could probably be =
easily integrated with mushroom production. However termites do not =
develop quite as quickly as many other insects thus the start up time =
might be several years before the population could consume at the rate =
of spent compost delivery. Containment and rearing facilities would =
have to take into account their social habits.
Termiticulture may not be feasible out of doors in the temperate part of =
the northern hemisphere. The southern tier state of the US would be =
adequate for a few genera such as Reticulitermes and Amitermes, but =
large scale termiticulture would work best in conjunction with tropical =
agriculture, especially wherever there is a large cellulosic waste =
component in the food processing. Termite production could also be =
integrated with dairy and livestock production as a manure management =
system. Matching species to wastes and to stage of waste would be =
necessary.
If anyone knows of an innovative tropical agribusiness that would be =
interested in putting up the capital for a pilot study, I'd like to hear =
from them.
Sincerely,
Tim Myles
++
Dr. Timothy G. Myles, Faculty of Forestry, University of Toronto, 33 =
Willcocks Street, Toronto, Ontario M5S 3B3, CANADA. t.myles@utoronto.ca =
phone: (416) 978-5755 fax: (416) 978-2403 home phone (905) =
877-9351