【推荐1】In the oceans, concrete is the main construction material, accounting for more than 70% of coastal and marine construction such as ports, coastal defence structures and waterfronts. "Concrete is damaging in the ocean because, to put it in place, natural ecosystems are destroyed," says Alex Rogers, director of science at REV Ocean, a not-for-profit company studying ocean health and raising awareness of global impacts on the marine environment. "Concrete is a conventional material, and it is low cost. But really, in this day and age, we should be looking at alternative materials that have a lower impact on the environment."

Those alternatives might already be here. Among them is a substance called ECOncrete, developed as an eco-friendly concrete. ECOncrete produces bio enhancing concrete products intended to protect coastlines and marine resources. This is achieved by using a mixture made almost entirely of by-products and recycled materials, and is thus nearly carbon neutral. This mixture is combined with up to 70% slag cement(a by product of the steel industry which has a low carbon footprint) and is beneficial for marine concrete thanks to its high chloride resistance. The overall result is a low-carbon concrete.

Furthermore, unlike traditional concrete, which is highly alkaline, the specially designed concrete has a pH value near to that of sea water, which helps to promote the growth of marine species such as crabs, molluscs, clams, mussels and oysters. ECOncrete's products are already in use across eight countries and six different seas, from seawalls in Hong Kong to the Port of Rotterdam.

However, Beth Strain, a lecturer in marine biology and a project leader for Australia's National Centre for Coasts and Climate, says the evidence for eco-friendly concrete as a better surface for marine organisms is very mixed. “It can be location specific. We did an experiment in 15 harbours around the world with the same type of concrete surface complexity. Largely, the results were positive, but in Penang, Malaysia, for example, using eco-friendly concrete that would theoretically retain moisture and be better for organisms to survive on made no difference.” Strain thinks this is because of the area's typhoons, which make the area very wet already, so the features of the concrete aren't a big help.

“There is a degree of difference and each location will have its own environmental challenges,” says Strain.

Nevertheless, from multiple perspectives, it appears that nature-based solutions are definitely the way forward.

【推荐3】The heavy use of fossil fuels over the last 150 years has released massive amounts of greenhouse gases, which have caused Earth to warm up. Just planting trees and protecting forests won’t solve the problem. When the plants and trees die, the carbon they’ve stored gets released again. That means humans need to come up with ways of removing carbon from the air and storing it. This is called Direct Air Capture (捕获) (DAC).

A company called Heirloom has just opened the first DAC plant in the United States. Heirloom’s process uses limestones, a kind of common rocks, to capture carbon dioxide (CO₂). The company heats up the limestones to separate out the CO₂, which are then locked away in concrete. Heirloom uses renewable electricity to produce the heat, so the process doesn’t produce more CO₂.

The process is extremely expensive, but many large polluting companies are paying Heirloom to share the credit for removing CO₂. The new plant can remove 1,000 tons of CO₂ a year. That’s a tiny amount compared to how much carbon needs to be removed from the atmosphere. But the company says it hopes to remove a billion tons per year by 2035.

Graphyte is another US company working on DAC. The company claims its carbon capture method is very cheap, mainly because Graphyte lets plants do the work of capturing CO₂. The company collects unwanted plants and wood products and dries them completely so they can’t break down. Graphyte says its process doesn’t use much energy and can work anywhere. The plant and tree material the process uses would release carbon if it weren't treated.

Not everyone is excited about carbon removal. Some people worry that focusing on removing carbon could take attention away from more important climate actions, like switching from fossil fuels to renewable energy. But experts say even if people stopped using fossil fuels tomorrow, the climate crisis wouldn't go away. There are still many greenhouse gases, like CO₂, in our atmosphere. The world needs to end fossil fuel use and pull carbon out of the air.

【推荐2】On a farm in England, Gavin and Alice Munro are taking sustainability (持续性) to the next level: they harvest trees which they grow into chairs.

The couple have a furniture (家具) farm in Derbyshire where they are growing 250 chairs and 50 tables. It is their answer to what they see as the inefficient (效率低的) process of cutting down mature trees to create furniture.

“Instead of growing a tree for 50 years and then cutting it down and making it into smaller and smaller bits ... the idea is to grow the tree into the shape that you want directly. It’s like a kind of 3D printing,” said Gavin.

Part of the inspiration for the idea came when Gavin was a young boy. He found an overgrown bonsai tree (盆景树) which looked like a chair.

The 44-year-old man began experiment in 2006. In 2012, Gavin and Alice set up the company Full Grown. Within several years, the couple developed the most effective way to shape a tree without limiting its growth. They guide shoots (新枝) heading in the right direction, rather than forcing them the wrong way against their natural growth.

The average chair takes six to nine years to grow and another year to dry out. The labor and time involved in producing the organic pieces mean they do not come cheap. Chairs sell for￡10,000 each and tables for￡2.500 to £12.500.

【推荐2】Looking out of the window of his truck, Bob Fitzgerald sees dying forests and empty farmland. Fitzgerald says the land has been in his family since the 17th century. “I can show you the land around here that people grew tomatoes on when I was a little boy. And now it’s gone.”

Climate change is making things worse. As sea levels rise, salt water is entering rivers and other waterways. As a result, the land is becoming too salty for crops (庄稼) to grow on. Hundreds of millions of people will have to move inland because of rising waters.

Kate Tully, a researcher in the University of Maryland, wants to keep coastal (沿海的) farmers in business as the seas rise. She has seen the forests filled with pine trees killed by the increasingly salty soil. The United States Department of Agriculture gave Tully and other researchers $1.1 million to study the problem. She and her team hope to give farmers ways to stay on their land.

They are testing different crops on pieces of land around the Eastern Shore. “Sorghum is my new favorite crop because it can grow without rain and it can grow with lots of rain.” The grain crop (谷类庄稼) may be a good choice to feed the nearly 600 million chickens kept in the area each year. As farmers know, chickens can deal with salt, dry weather conditions and heavy rains. Yet just being able to grow a crop is not enough. The crop has to bring in money.

Some people believe the land should be given back to nature. They say the fields should be turned into wetlands, which are popular with duck hunters (猎人). “There’s money in duck hunting,” Tully said. “Hunting organizations will pay farmers for hunting on their land. Farmers could make a lot of money from duck hunting.”

Tully and her team are just getting started. It will be a few years before they really understand how to save the farms.

【推荐3】It’s mid­February and along Britain’s south coast gilt­head bream (鲷鱼) are swimming from the open sea into the river mouths. And this summer, countryside visitors throughout southern England will catch sight of blue flashes as small red­eyed damselflies fly across starry ponds. Both events are happening much further north than they would have 20 years ago.

Fingers point at climate change. As areas become too hot or dry, many wildlife populations are declining, while some species are showing up in places that were historically too cold or wet.

Our team, led by Alba Estrada, wanted to explain this phenomenon. If we could predict which species can and can’t colonise (移居) in new locations, we could decide which are most in need of conservation.

How far individual animals or plant seeds can move was long thought to be the most important factor. But according to our findings, other characteristics also turned out to be highly important. For example, how quickly plants and animals can produce, how well they can compete with other species for resources, and what kinds of food they can eat or habitat they can live in.

The result of this is that we might be able to predict which animals will survive under climate change. The wood mouse is found throughout continental Europe. As climate changes, we think the mouse will move north because it can breed quickly, live in lots of habitats, has a broad diet, and individuals can travel a long way. And consider the European ground squirrel. We think it might stay just in southeast Europe because it can only live in grasslands and climate change won’t suddenly turn farms and forests into meadows (草地).

It’s encouraging to know that some species are doing well under climate change. There are some headaches, however. Those gilt­head bream are feeding on the local shellfish, which might be taking food away from the native fish. Small red­eyed damselflies look great, but they could become all too common around British ponds and outcompete native species. Climate change is once again posing us some tricky conservation questions.