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Six
steps to abundant drylands in Brazil
Imagine
this scene: to one side, scorched earth, with tiny castor bean plants dying
of thirst. Five yards from that, a green wall two meters high, a complex
mixture of castor beans, pigeon peas, jack beans, sesame, cowpeas, opuntia (nopales-
an edible cactus) fodder trees, and young fruit trees. Below this mass, the
soil is so humid that one might think that it had just rained. Result of
irrigation? No. This is the result of an agricultural model appropriate to
drylands: polycultures.
There is
a myth which says that in the Brazilian drylands, called “Sertão,†it rarely
rains. In fact in the Sertão it rains “enough†(sometimes a lot!) for its
ecosystem. There is an enormous mix of flora, fauna, medicinal herbs, fine
woods, fruit, fodder and annual crops adapted to this climate. The problem
is the loss of rainwater and not the lack
of rain! Dryland research, confirmed by the EMBRAPA of Petrolina, show that
the present agricultural model leads to a loss of 80% of rainwater,
through wind, sun, and runoff. In the rainy seasons, the rivers in the
Sertão overflow their margens – where there are floods, there will be
drought, because that water has been lost to the system!
Therefore, the problem of
the drylands is wrong management and not lack of rain. In order to
create a form of sustainable agriculture, even in drought years, one needs
to take six simiple steps:
- Plant
windbreaks – the dry wind can carry off up to
1,500 mm of humidity – three time more than it rains in the region! Just
this one strategy could result in enormous advantages to the farmer.
- Cover the
soil – Mulch, besides shading the soil from
the direct rays of the sun, stores humidity, keeping the soil surface
cool, a fundamental condition for the presence of beneficial soil life.
In fact, the process of decomposition of this mulch material produces
water as one of its sub-products.
-
Polycultures – a diversity of plants takes
adavantege of every drop of rain, amply proven by the Polyculture
Project of the Bahian Permaculture Institute. With the intense
utilization of space by a variety of plants, the farmer harvests eight
to fifteen crops where before he harvested one or two, increasing
tremendously the number of products for sale and for his table.
Polycultures create a situation of financial and food security within
which the farmer can risk trying out new crops. A second advantage of
polycultures is the immense web of roots formed under the soil surface,
which keep it open and humid, making sure that all humdity remains
available to the plants, and does not easily slip below the root zone.
- Plant trees
wherever possible – Locally adapted trees produce fruits and fine
woods and firewood even in El Niño years, leaving the local microclimate
cooler and more humid. In spite of the belief that trees take a long
time to produce, with polycultures it is possible to have an
agricultural system which after one year produces short-term crops such
as elephant grass, cassava, opuntia, with two years produces dwarf
varieties of cashew, serigüela and fodder, with four years anonas,
cashew , guavas, and with five years the first woods for fence posts.
Thus, the farmer implements an integrated agroforest which produces over
the years with a minimum of intervention and without having to wait
years in order to start harvesting from the plot. Ideally the farmer
would leave a small area for annual crops (corn and beans, etc.) and
would transform the rest of his property into mixed agroforests (which
could also be forrage agroforests for his animals), a much more stable
proposal for an instable climate. In fact, this agroforest wil create
its own cooler microclimate, as the temperature difference sun-shade is
8 degrees centigrade!
- Plant
fodder systems for the animals – In drought
pasture dies, but the bushes and trees continue green. Having specific
fodder systems would avoid the necessity of turning the animals into the
crop stubble, scraping the fields clean of all organic material, to cook
in the sun, as is the case today.
- Put
cisterns on all roofs – A hundred meters of
roof surface can catch twenty thousand liters of water in the worst
years, and up to seventy thousand in better rain years.
The problem of the
Sertão, therefore, is not lack of water. It is the lack of information and
of extensionists working with a model which is appropriate for this climate.
The success of the Polyculture Project, which is into its fifth year, proves
that non-irrigated agriculture in the Sertão is capable of providing
abundance and income, even in drought years.
Marsha Hanzi
is Northamerican, permanent resident in Brazil for
30years, founder of the Bahian Permaculture Institute, author of the manual
“Permacultura- O SÃtio Abundante†(Permaculture- the Abundant Farm)
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