Earth & Environment

Cities can break up passing storms, plus wild boar contamination, altered spider sense and more in this week’s news

Side of fungal compounds with wild boar The industrial age has exposed people to numerous chemical contaminants, but the ancient tradition of feasting on wild boar did as well. When carrying out routine food-inspection tests on wild boar meat, German researchers detected unusually high levels of a previously unknown substance from a class of halogenated compounds that typically persists in the environment and the food chain. Further investigation revealed the suspicious compound is made by a mushroom that boars delight in, the researchers report in an upcoming Journal of Agricultural and Food Chemistry . The team concludes that humans have likely been exposed to this contaminant for as long as they’ve been eating wild boar, an ancient practice that continues today. — Rachel Ehrenberg Warming shifts forest’s carbon stores As forest soils warm — and they’re expected to, with climate change — they will release substantial amounts of carbon, a seven-year field study finds. After experimentally warming the forest soil 5 degrees Celsius, they showed this increase also fostered an increased uptake of carbon by trees. By the end of the study the bonus storage by trees almost totally compensated for soil carbon losses, scientists in the United States and China reports online the week of May 23 in the Proceedings of the National Academy of Sciences . Boosting the trees’ carbon uptake, the team says, was a temperature-related increase in the availability of soil nitrogen, a fertilizing nutrient. — Janet Raloff Weed killer confuses spiders Glyphosate, the active ingredient in many weed killers, can make it hard for male wolf spiders to sniff out a willing mate. Although the chemical is not toxic to the spiders, researchers at Miami University in Oxford, Ohio, show that it impaired a male’s ability to detect a female’s scent. Through tests in the field and the lab, the researchers showed that males normally ignore the weed killer’s scent. Males are also twice as likely to ignore a female if she’s in a glyphosate-treated site. And fast-trekking males were most likely to miss a virgin female, the team reports online in Chemosphere , ahead of print. — Janet Raloff Cities alter storm intensity Urban areas have “a strong climatological influence on regional thunderstorms,” scientists conclude in the May Journal of Applied Meteorology and Climate . An international team analyzed 91 summer T-storms passing through the Indianapolis region. Storms tended to be “organized” and exhibit a medium intensity over rural regions. As storms approached the city, their structure changed in 71 percent of daytime storms and 42 percent of nighttime ones. Many storms broke or skirted the urban area. Downstream, they typically remained tiny — or coalesced and gained energy, becoming huge super-intense events. The scientists suspect the changes trace to urban areas’ tall buildings, pollution and heat-island effect. — Janet Raloff