Eco warriors

Introduction

Earthworms can now be used to help plants clean up soil faster. Researchers at Reading University at Berkshire in the UK have found that subtle changes occurred in metals as earthworms ingested and excreted soil. These changes make it easier for plants to take up toxic metals from contaminated land. Earthworms are ideal soil detectives and have evolved a mechanism that allows them to survive in soils contaminated with toxic metals including arsenic, lead, copper and zinc, the researchers said. They found that properties of metals in the material excreted from earthworms were a little different from those found in the rest of the soil. Some plants can pull out toxic metals from the soil and incorporate them into their tissues, from where the metals can be removed. But this process can take a very long time. Earthworms make the metals more readily available to plants, speeding up the process.

Source

Down To Earth, October 2008