DAWN.COM

Today's Paper | May 23, 2024

Published 13 Oct, 2008 12:00am

Earthworms intestine of the soil

ARISTOTLE called worms the intestines of the soil but the multi nationals loath competition with the world's natural systems, that create energy and productivity in a sustainable manner.

Former president Sardar Farooq Ahmed Leghari kept on egging me to get earthworms from the US. Our earthworms are malnourished and not as productive as the American ones. So I asked a friend to send me some earthworms from there.

When I received them, I promptly set about multiplying them and then used them where fertiliser and chemicals were not applied. Nurseries were created all over the country particularly in Balochistan. That effort was destroyed by those who came into power afterwards.

The earthworms have a significant role in raising productivity of crops and maintaining sustainability of soils at a cost that might surprise everyone. Though a macro-organism, earthworms loosen the soil by burrowing and digging, they help decompose plant tissues and through their waste help create beneficial compounds for plant use.

The earthworms break up soil hardpans (natural occurring and in the rice wheat system when we kaddoo the soil), drill miles of burrow that soak up fast falling rains (during monsoon and thus help the drainage of the soils), help plants root more deeply into the soil (no lodging as is seen in the rice fields these days) and help balance nutrients and loosen compaction.

The earthworm does not ride a Merck or Lexis or a BMW and is a friend of the earth and improves productivity in many ways, at the same time, it helps balance the natural systems in the earth. How ? Some of the ways are indicated as follows

Water absorption The earthworms dig pencil sized vertical tunnels that allow rainfall to flow deep into subsoil so that even hard pans can soak in rather than run off and erode the ground. Water runs through the worm tunnels and soaks slowly from these underground conduits into the surrounding soil so that the entire root zone is evenly watered. This is particularly important in heavy clay soils. These earthworm tunnels help prevent water logged, anaerobic soils by removing excess water from the root zone.

Aeration From the surface to the depth of three to five feet, the earthworms bring oxygen down by way of tunnels to stimulate microbial conversion of minerals into plants nutrients. The aerobic depth of the soil is increased and carbon dioxide is more effectively moved up to the soil surface and released.

The linings of tunnels are rich with glue like nutrient sugars or polysaccharides that help the tunnels remain in place for years. The oxygen, nutrients, and rich bacterial life associated with the tunnels encourage plant growth down in to subsoil moisture.

Root growth stimulation The earthworms pull scraps of decaying matter from the ground surface down into the network of tunnels that enables the root to grow six or seven inches a-day through otherwise compacted soils. As generations of root residue fill these tunnels, deep moisture also moves by osmosis up through the pipelines to feed roots near the surface.

Tilling The worms bring minerals from the subsoil to the top. They also bring the debris to the top soil and then help to digest the raw residue and convert them into nutrient-rich humus and other compounds beneficial to plants.

Hormones The earthworms break down crop growth inhibitors such as phenols and formaldehydes from decaying residue and add to plant growth stimulants containing auxins and cytokinins. The worms can treat 50 tons of top soil per acre per year. Their castings encourage vigorous root growth.

The earlier species obtained from the US has been lost due to neglect of the NARC. Now it has acquired three new species from elsewhere and it is intended to rear them and pass them on to the poor farmers who cannot afford chemical fertiliser.

With it a package of bio-pesticides will also come that will be friendly to the earthworms and bio-hormones, for the farmer must understand that growth of plants is not only through root structures but also through leaves provided nutrients are given on the leaf surface. The third option being exercised is that the farmer will be educated on hands on basis in the NARC. Such a programme has already been initiated and the initial steps are going to be taken.

These are only a few of the advantages. Remember the natural balance is not to be disturbed.

Read Comments

In anticipation of mangoes Next Story