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Written by Administrator
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Sunday, 11 September 2005 |
by Matthew Werner, University of California, Santa Cruz, from our issue #5
Jorge Ramon Cuevas, researcher and self-professed rebel, has been
working since 1985 to develop technologies for using earthworms to
transform organic wastes into fertilizers. According to Cuevas, "When I
started this work, people thought I was crazy." But since 1989, with
the advent of the worst economic crisis in Cuba's history, he and other
scientists working on sustainable agriculture and development issues
have been thrust to the forefront of Cuba's efforts to survive in the
face of incredible adversity.
The economic crisis, known as the Special Period, was brought on by
reductions in aid from and trade with the former Soviet Union and other
Eastern European countries. Importations of fertilizers, pesticides,
animal feed and petroleum products from these countries have been cut
by as much as 80%. The problem has been compounded by the tightening of
the U.S. embargo against Cuba. As a result, food is scarce in Cuba, and
caloric intake per capita has dropped by 1/3 since 1989. In response to
food shortages, many Cubans are planting home gardens, and in Havana
there are 30,000 community gardens.
But The Worm Man of Cuba is cheerful and optimistic. In some crops, he
has found that earthworm castings can replace up to 70% of fertilizer
inputs. For crops where synthetic fertilizers were replaced by 45
metric tons/ha of cow manure, he has found that the manure can be
successfully replaced by 4 metric tons/ha of earthworm castings and
production is improved by 31%. This reduced bulk of vermicompost
fertilizers has the added benefit of reducing transportation costs. The
earthworm castings contain 2% nitrogen, 1.5% phosphorous, 1.5%
potassium and 65% organic matter. The castings are relatively stable
and can last up to 5 years in the soil.
Cuevas has experimented with several species for vermicomposting,
including Pheretima species brought over from the Philippines, and
Lumbricus rubellus and L. terrestris obtained from Mexico. His work
currently focuses on the 2 species that he feels are most useful under
Cuban conditions: Eisenia foetida andrei, which he finds to be more
tolerant of the humid, sub-tropical Cuban climate than the subspecies
Eisenia foetida foetida, and Eudrilus eugeniae, which is called the
African Red Worm. Eudrilus eugeniae is not as successful as E. foetida
because it is less tolerant and prone to escaping when conditions
aren't quite right. However it produces more protein than E. foetida
and is especially useful as a supplemental animal feed.
I visited a vermicompost production center in Pinar del Rio, the
largest of 172 centers around the country that produced a total of
70,000 tons of vermicompost in 1993. The center I visited began in the
1980's with 2 small boxes of earthworms received from Cuevas. In 1993
it produced 10,000 tons of vermicompost. When it is available, chicken
manure is used in a 50/50 mix with cow manure to feed the worms .
Cuevas is also experimenting with sugar-cane processing wastes and pig
manure. The city of Havana pumps 5 cubic meters/sec. of human manure
into the ocean, but Cuba apparently is not quite ready to begin
utilizing this valuable resource.
Cuevas has developed a two-box vermicomposting system for processing
household food waste that he calls the "Sanitary Box." He currently has
pilot projects going in two restaurants, an eco-tourism hotel, and a
169-household community. The sanitary boxes (60 x 40 x 50cm high) are
begun with about 1500 worms with the population building and maintained
at about 20,000 per box. The earthworms are fed kitchen scraps and
paper wastes in the first box until it is full. Then the second box,
which is slatted on the bottom, is placed on top of the first and food
provided. The worms move up through the slats to where the food is. In
this way the earthworms separate themselves from the finished
vermicompost.
The worm man of Havana is a familiar face these days. His weekly TV
show Entorno, about the environment, and the flora and fauna of Cuba,
is one of the most popular shows in the country. His research program
is carried out mainly at the Institute of Soils and Fertilizers in
Playa, near Havana. Cuba is also exporting earthworm technologies to
other countries. In 1992 Cuevas helped set up two units in Peru that
are producing 1200 tons of earthworm castings. This year he will travel
to Venezuela to set up a vermicompost project utilizing supermarket
wastes.
Werner traveled to Cuba as a part of the group Global Exchange, 2017
Mission St., San Francisco, CA 94110; 415-255-7296, which organizes
exchanges and monthly study trips there. |
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Last Updated ( Sunday, 18 September 2005 )
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