Most gardeners know that earthworms (蚯蚓) help keep soils healthy. Now scientists have assessed just how important their underground activities are to global food production — and how to protect them.
In research published this September, scientists found that earthworms may contribute to more than six percent of global grain production every year, because of their crucial role in soil ecosystems.
Worms help to break down dead plant material, releasing nutrients plants need to grow, and their tunneling (挖隧道) helps plant root growth. Evidence suggests they also help plants protect themselves against common soil-related diseases by stimulating their defenses.
“Their contribution may even be larger,” said Steven Fonte, an associate professor at Colorado State University in the United States who co-authored the research. “This is because earthworm populations are likely underestimated in many places, especially in the tropical areas, due to a lack of research and funding in the global south.” he explained.
The authors said their findings represent one of the first attempts to quantify the contribution of a beneficial soil organism to global agricultural production. They found that earthworm contribution is especially high in the global south, contributing about 10 percent of total grain production in sub-Saharan Africa and roughly eight percent in Latin America and the Caribbean. They owed this to soils there generally having higher acid and clay content and being less exposed to fertilizer (肥料), increasing the role earthworms play in plant growth.
Scientists figured that earthworms are threatened by today’s intensive and chemical-heavy agricultural techniques. Agricultural and environmental policies should support earthworm populations and soil biodiversity to promote more sustainable development. Measures could include reducing the use of land for growing crops, cutting the use of poisonous chemical substances, and increasing the application of worm food sources. “Soils are estimated to contain approximately half of all biodiversity on the planet and are incredibly important for biodiversity conservation efforts,” Fonte said.
【小题1】How do earthworms benefit the soil ecosystems?| A．By increasing the number of plant roots. | B．By reducing fertilizer’s effects. |
| C．By helping plants against certain diseases. | D．By breaking down nutrients. |
| A．The good soil quality. | B．The advanced agriculture. |
| C．The supportive policy. | D．The earthworm-friendly climate. |
| A．Expanding the farming land. | B．Providing healthy food for them. |
| C．Banning intensive agriculture. | D．Using fewer harmful chemicals. |
| A．Earthworms: An Assistant to Soil Health |
| B．Earthworms: Their Threats and Conservation |
| C．Earthworms: The Decisive Factor in Biodiversity |
| D．Earthworms: A Contributor to World Food Production |
