Global Warming

American Trees Are Moving West Due to Climate Change

As the consequences of climate change strike across the United States, ecologists have a guiding principle about how they think plants will respond. Cold-adapted plants will survive if they move “up”—that is, as they move further north (away from the tropics) and higher in elevation (away from the warm ground).

A new survey of how tree populations have shifted over the past three decades finds that this effect is already in action. But there’s a twist: Even more than moving poleward, trees are moving west.

About three-quarters of tree species common to eastern American forests—including white oaks, sugar maples, and American hollies—have shifted their population center west since 1980. More than half of the species studied also moved northward during the same period.

These results, among the first to use empirical data to look at how climate change is shaping eastern forests, were published in Science Advances on Wednesday.

Trees, of course, don’t move themselves. But their populations can shift over time, and saplings can expand into a new region while older growth dies in another.

While climate change has elevated temperatures across the eastern United States, it has significantly altered rainfall totals. The northeast has gotten a little more rain since 1980 than it did during the proceeding century, while the southeast has gotten much less rain. The Great Plains, especially in Oklahoma and Kansas, get much more than historically normal.

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Disease

China bird flu: 1st case in Shanxi Province

According to the Health and Family Planning Commission of Shanxi Province, a 66-year-old woman from Datong, Shanxi Province has contracted avian influenza A(H7N9), becoming the first such human case in the province. The patient is currently in serious but stable condition.

Foot and Mouth Disease Outbreak in Rwanda

The Ministry of Agriculture has banned livestock movement from Nyagatare District following an outbreak of foot-and-mouth disease in the area. The disease was first detected on Tuesday in some cows in Gabiro area. Local farmers supply more than 60 000 liters of milk per day to local milk processors. The ban will result in a substantial loss to the local milk and beef cattle industry.