Characteristics and processes of natural ecosystems can be used
as the basis for designing sustainable farm systems. This is, however, conditional to proper observation and collection of information for learning about the beneficial features of nature, as
well as in understanding the various natural processes. The international development organisation VECO collaborates in
Indonesia with more than 40 local NGOs, spread over 7
provinces, on the development of sustainable agricultural systems that can help to alleviate food insecurity.
LEISA developments
In mountainous Indonesia, soil and water conservation is an
obvious precondition for sustainable agriculture. Frequent losses
by erosion not only oppose basic ecological principles of LEISA
(“optimising nutrient availability and cycling”) but also harm
soil life and, therefore, affect the soil negatively, both quantitatively and qualitatively. When VECO partner organisations start
a new agricultural programme with rural communities, soil and
water conservation is, generally, a good starting point. After
making an inventory of the local conditions during a PRA exercise, programme staff and farmers are ‘fresh’ and eager to get
going, while the principles of building erosion structures are
quite straightforward and, by now, understood by many. In this
way some quick first results can be achieved which have an enormous impact on further LEISA developments.
Using the principles of agroforestry, shrubs and trees can be
added to protect and stabilise man-made erosion control structures. However, in cases where soils are not deep and slopes
rather steep, experiences from natural forests show that tallgrowing trees can be a hazard, and are frequently the cause of
landslides during the rainy season. Local farmers in the district
of Mamasa, on Sulawesi, recognise this danger and, therefore,
plant only shrubs on such slopes and frequently prune and lop the
woody species, which tend to grow tall.
Cover crops are in most agricultural development programmes
another means of curbing erosion. The soil-creepers, mostly leguminous plants, can also serve as soil fertility improvers. But what
could be done in situations where soils are rather acidic and common cover crops do not grow well? Or in cases where cattle roam
freely around and could destroy the cover crop by trampling or
browsing?
Learning from local insights
Ethnobotanical surveys often provide important information and
local insights with which such issues could be tackled. During an
ethnobotanical study in the area of Balla Satanatean village in
Mamasa District, an answer was discovered for the first question.
Soils here are acid and farmers use lime to increase pH on their
fields. The common, natural soil cover here is a creeping fern,
paken (Gleichenia linearis), and large areas on slopes have been
Production of different crops using Urea (250 kg/ha)
or compost (10 ton/ha)
Crop Yield with Urea Yield with compost
(kg/ha) (kg/ha)
Rice 1,200 2,680
Maize ,800 1,460
Groundnuts ,975 1,125
22
LEISA MAGAZINE . OCTOBER 2002
colonised by this “wire fern”. Local adat (customary law)
demands great respect for the functions of this plant and people
will think twice before they do anything that might damage the
protective ‘blanket’formed by this fern. The soil-holding capacities of paken are so well understood that most farmers plant this
species on dikes around their sawah (irrigated rice fields).
Farmers in Ngada District on Flores appreciate, already for a
long time, the natural presence of the “weed” putri malu
(Mimosa diplotricha or giant sensitive plant). This fast-growing
species can provide a quick cover on fields between cropping
periods or during a fallow. Covered with many small thorns, it is
not a crop that invites animals, and people alike, to walk through.
According to farmers it is not easy to clear putri malu afterwards,
but they take that for granted since it is an excellent soil
improver, cover crop and soil binder against erosion.
Another problem that many farmers on Flores face is very hard
soils. Low in organic matter after continuous use, soil compaction
makes it impossible to plough such soils. Women lament that they
cannot grow vegetables or fruit trees near the homes because the
soil has become as hard as a rock. Perhaps even worse, because in
rocky places there are still some plants and trees that grow.
This last observation has been a challenge to the community.
If plants can grow in the wild in places where there are only
rocks, then why can plants not grow in their hard soil?
Pits of 30x30x30 cm have now been chiselled out and filled
up with soil from other places mixed with organic material.
Vegetables and fruit trees have been planted in this olah lubang
(pit planting) system. The first results are promising and the
hope is that by bringing back some life to this hard soil, the soil
will eventually become healthy.
Maintaining soil fertility
To keep the soil in place is one thing. To keep soil fertility in pace
with day-to-day agricultural requirements is another. Farmers in
Indonesia are searching for alternatives to the chemical fertilisers
they have been using since the Green Revolution started.
Convinced that inorganic fertilisers have destroyed many of the
qualities of their soil, and stressed because of the high prices of the
chemicals since subsidies were abolished, farmers in the VECO
programmes are, for instance, experimenting with liquid manure.
This manure is made by fermenting large amounts of leaves of certain shrubs and trees in containers with water. After a few weeks,
the concentrated liquid is diluted with water and used as a fertiliser
on small rice fields, vegetable plots or young fruit trees. Reactions
from farmers are all very positive. They observe good growth and
more healthy plants. There is less damage by pests and products
such as onions can be stored for a much longer period compared to
produce from fields treated with chemical fertilisers.
During technical monitoring and evaluation meetings, the
Wise lessons from Mother Nature
23
important soil processes concerning mineralisation and nutrient
availability are explained and discussed. The accelerating effect
that N and P fertilisers have on the decomposition of soil organic
matter is always a hot item of discussion. Initially, a bonus effect
is created by increasing the availability of macro and micronutrients to plant roots. On the longer term, this priming effect
causes a larger fraction of the soil organic matter to be broken
down annually. Arguably, this is the most important factor why
the Green Revolution scored its early successes but finally
caused serious problems for main soil qualities.
When confronted with this information, it is not so difficult
for farmers to draw a parallel between the use of chemical
fertilisers and the use of their liquid manure. Since the liquid
fertiliser contains only water, nutrients and microbes, they can
only agree that chances are high that similar priming effects
could cause new problems, especially because of decreasing the
content of soil organic matter.
Therefore, it becomes imperative that organic material of a
certain quality is regularly added to the soil. The usual green
manures are not applicable since research in alley cropping
has shown that the easily decomposable leafy material from
leguminous species contributes to a priming effect and does
not add significantly to soil organic matter. Animal manure
would be fine, but not all farmers keep animals while quantities
of animal manure are often not sufficient. This leaves compost as
the better option. Especially compost made out of fibrous
material such as rice straw and alang-alang grass (Imperata
cylindrica) could provide the necessary, long-lasting organic
supplement for soils. Crop yields are significantly higher with
the application of compost in comparison to inorganic fertilisers
as seen in the table. Compost starters are popular amongst
farmers and have become cheap and accessible due to farmer
innovation (see box).
Conclusion
In order to imitate natural ecosystems in our pursuit of developing
sustainable agricultural systems, we – development agents and
the farming communities - should be prepared to observe well the
many different components, and ingenious arrangements between
components, that make up such a natural ecosystem.
■
Ambarwati D. Rahayu (Programme Officer) and Rik Thijssen (Advisor Sustainable
Agriculture), VECO Indonesia, Jalan Letda Kajeng 22, 80234 Denpasar, Bali.
Email: fadori@denpasar.wasantara.net.id
Farmer innovation in compost-starters
During a study visit in 1998, to an extension institute in Bogor, the use of a
commercial compost-starter EM4 (“effective microbes”) was demonstrated
to farmers from Bandungrejo village in Malang District, East Java. This
technology, developed by a Japanese biotechnology professor, was, of course,
tried by the farmers once they got home. The conclusion of the group was that
the process of composting mixtures of rice straw and other organic waste was
indeed accelerated by using EM4. Where it would take normally months for
rice straw to degrade, the new technology took only few weeks!
However, the expenses of buying the litre bottles of EM4 were relatively
high (about 25,000 Rupiah or US$ 2.80). One of the group members, Mr.
Kusno, therefore decided to try to develop his own compost-starter. From
their visit to Bogor, it had become clear what natural processes and
components were important for a more rapid composting process. Mr.
Kusno, who had ample experience with the fermentation of cassava roots
to the local food product tape, reasoned that if the ragi (“yeast”) used was
able to make the hard cassava root soft, than maybe it would even be able
to break down the fibres of the rice straw.
Using the ragi for making tape from cassava roots, they found it is
possible to produce mature compost in only a matter of weeks. The
compost was analysed by the Soil Laboratories of the Agricultural
Department of Brawijaya University in Malang. A cost-benefit study was
done and also proved very favourable - using compost could save almost
50% of expenses on chemical fertilisers. While it could even be lucrative
to produce compost for selling, since production costs for 200 kg of
compost was about 10,000 Rupiah, while compost was sold for 200
Rupiah per kg.
The results of the experimentation by Mr. Kusno and his farmer group
has triggered off a complete new thinking about composting. After
extension officers had shown them how to make the ragi themselves,
farmers have also started experimenting with alternative ingredients to
make effective compost-starters. While the ragi for cassava tape is based on
micro-organisms from the roots of laos (Languas galanga), starters have
now been developed using roots of other plants as well as over-ripe fruits.
Mr. Kusno died in 2000 at the age of 58 years. His work will always
be remembered by the many farmers in Indonesia who implement
‘his’ technology under the name pupuk ragi Kusno (fertiliser from Kusno’s
ragi).
LEISA MAGAZINE . OCTOBER 2002
Farmers plant the creeping fern paken (Gleichenia linearis),
a natural soil cover by traditional law protected, on dikes around
their sawah (irrigated rice fields).