soil

First there was Peak Oil, the idea that there’s only so much oil out there and we may have reached or even passed a turning point in global oil production. In his 2007 book “Peak Everything,” author Richard Heinberg said it’s not just fossil fuels: Everything from population to food production to freshwater availability has its own point of no return.

Any gardener can tell you that earthworms play a major role in soil ecology. But that information hasn’t always been common knowledge. Charles Darwin was one of the first to study earthworms, and in 1881, he discovered the curious fact that many species leave behind calcite crystals as they work their way through the soil. Now, new research might shed some light on the enduring mystery of how and why earthworms produce the crystals.

Don’t look now, but a slumbering beast rests in the north. It’s not news that the North American Arctic, where trees dare not grow, contains immense amounts of organic carbon in its soils. But according to a new study, past estimates of organic carbon concentrations in Arctic soils are too low — and that has some scientists worried about vast amounts of carbon being released as temperatures warm.

Beginning in the 1970s, international aid agencies dug hundreds of thousands of wells in Bangladesh to help people access clean drinking water. The effort curbed diarrheal diseases, but it led to a new problem: arsenic poisoning.

Arsenic occurs naturally in some rocks, including formations throughout the Himalayas. When these rocks weather, the groundwater can become contaminated with arsenic. At high doses, arsenic is lethal. But even small doses can cause cancer and other health problems over time.