Beavers(海狸), like humans, change their surroundings to fit their needs. Known as nature’s engineers, they tear trees down to build homes to live in and dams to raise water levels for protection from endemics. Dams also slow water’s flow while blocking sediment(沉积物)that would otherwise flow downstream. The resulting wetlands often attract wildlife diversity where none had existed. There are challenges, though. Beaver dams sometimes cause flooding, and most people prefer trees alive and upright.

Communities face a delicate balancing act, learning to coexist with beavers. Last winter, many people enjoying Winston Path became beaver fans as one furry family transformed Swallow Pond into an oasis for birds, frogs, turtles and deer.

Yet such activity caused concern. As beavers worked, they raised water levels about five feet. The increased depth allows beavers to survive underwater if the pond ices over. But county officials were concerned about how higher water would affect the soil bank supporting Winston Path.

To find a good balance between protecting the path and the beavers, the county introduced a “beaver baffle”- a pond leveler. Beavers often rush to fill holes in their dams. Baffles stabilize water levels by creating a hidden exit for high water to escape through the dam, unnoticed by the beavers.

People love the beavers but they also love the mature trees. Recently, Catherine Jones,18, organized a tree-caging event-putting wire cloth around large tree trunks to discourage beavers from biting them. It also protects people from injury due to random trees falling. “We cover the trees we don’t want them to eat, while planting periodically others they like,” said Jones. “We need to learn to give up a little of our wants to share the Earth’s resources.”

Swallow Pond’s 2023 project will restore proper water depth and improve wildlife habitat without creating problems for the path. The balancing act continues.

As reported in the journal Nature, one system can directly remove carbon dioxide from sources ranging from flue gas (烟道气) to the atmosphere by using electricity to induce a water-and-oxygen-based electrochemical reaction. This technological achievement could turn direct air capture (捕获) from edge industry into a promising front for climate change relief.

Most carbon-capture systems involve a two-step process: First, high-pH liquids are used to separate the carbon dioxide, which is acidic, from mixed-gas streams such as flue gas. Next, the carbon dioxide is regenerated from the solution through heating or by injecting a low-pH liquid.

“Once the carbon dioxide is trapped in these solvents (溶剂), you have to regenerate it,” says Haotian Wang, assistant professor at Rice University. “There are literally no chemicals produced or consumed with our process. We also don’t need to heat up or pressurize our device, we just need to put it into a power outlet and it will work.”

Another drawback of current carbon-capture technologies is their reliance on large-scale, centralized infrastructure. By contrast, the system developed in the Wang lab is an extensible, modular, point-of-use concept that can adapt to a variety of scenarios. “The technology can be scaled up to industrial settings-power plants, chemical plants-but the great thing about it is that it allows for small-scale use as well: I can even use it in my office.” Wang says.

Also the reactor can continuously remove carbon dioxide from a simulated (模拟的) flue gas with efficiency above 98% using a relatively low electricity input. Wang notes that the process has “no carbon footprint or a very limited footprint” if powered by electricity from renewable sources such as solar or wind. “This is great news considering that renewablel electricity is becoming more and more cost-effective,” Wang says.

It has been almost six and a half years since the American music group Pearl Jam published its tenth album. That changed Friday when the band dropped its eleventh collection, Gigaton. Critics (批评家) have noted that this new album includes hard rock. Entertainments Weekly called the music “a gathering storm of guitars”. In other words, there is some loud and wild music on Gigaton. But most reviewers agree that Pearl Jam continues to experiment with less traditional rock and roll sound on the album.

But back to the name of the album — Gigaton can also mean the weight mass equal to 1 billion tons. The word is most often used these days in stories related to climate science and environmental damage. In fact, former U. S. President Obama famously defined the word during a speech about climate change in Alaska and the Arctic. When discussing the huge yearly loss of ice from Alaska’s glaciers, he compared the amount to the size of the national Mall in Washington, as if it were a solid (固体的) block that stood almost 700 meters tall.

And climate change issues are at the heart of Pearl Jam’s Gigaton. The album picture shows icefalls in Svalbard, Norway. Svalbard is one of the northernmost places where humans live in the world. Some climate scientists say it is warming faster than any other place. Pearl Jam has spent most of its 30-year existence on environmental causes. The band and its members have won honors for raising money, climate change educational efforts and more. They also put money into environmental health projects to reduce the group’s carbon footprint.

Pearl Jam was officially introduced into the Rock and Roll Hall of Fame in 2017. The lead singer Vedder’s opening comments were about the environment. “So, climate change is real,” he said. “And we...cannot...cannot be the generation that history will look back upon and wonder why they didn’t do anything possible to solve the biggest danger in our time.”