【推荐2】A bike road in Krommenie, city in the Netherlands, isn't just helping people get around—it's also producing energy. The road, named Solar Road, is paved with solar batteries, which use the power of the sun to make electricity.

The project was created to show that the places where people ride, walk, or drive can also serve to make energy. And the solar-powered path, which was fixed last year, is doing an even better job at that than expected. So far, it's created enough electricity to power three houses for a year.

Many cities are already equipping rooftops with solar panels (镶板). By changing renewable sources of energy, city areas can reduce their dependence on fossil fuels, like coal, oil, and natural gas. Renewable sources of energy don't get used up or create pollution as fossil fuels do.

Roads could provide an even larger space than roofs to get energy from the sun, Sten de Wit, one of the innovators (改革者) behind SolarRoad, tells the business magazine Fast Company. "In the Netherlands, we have about 140,000 kilometers of roads—enough to go three times around the world and more. It's a huge area, more than all of the rooftops combined (联合的)."

To create the experimental bike path, the SolarRoad team laid down concrete slabs (平板) lined with rows of solar cells. A layer of glass, designed to be stronger, covers and protects the cells. Sunlight passes through the glass and into the cells, which change the rays into electrical energy.

Although the bike path was expensive to build, with the energy it's producing, it could pay for itself within 15 years. Sten de Wit thinks that by fixing solar-powered bike paths and roads, cities could make enough energy to power street lights, traffic lights, and even electric cars.

Most people don't notice that the bike path is different from a traditionally paved street, says de Wit. "That is exactly what we intend to achieve: roads doing whatever they have to do to be a proper road, while getting solar energy at the same time."

【推荐3】As everybody knows, tourism (旅游业) plays an important part in the development of a country, the life of people and so on. It can open our eyes to the outside world, bring us more knowledge, and make us feel good. However, tourism can also lead to pollution and many other problems to places of interest (名胜古迹).

Luckily, “Green Tourism” is now being promoted and developed around the world. As time goes by, people will begin to realize the importance of these places of interest. “Green Tourism” teaches a person to love nature more and to protect it by enjoying its beautiful scenery (风景) and learning more about it. “Green Tourism” is the best kind of tourism as its purpose (目的) is to let people enjoy natural environments including wild plants and animals, and of course the cultures of many places.

Compared with traditional tourism, “Green Tourism” is to learn more about nature and people. Traditionally, people travel around the world to enjoy themselves and pass time pleasantly. But “Green Tourism” are different. The tourists travel because they fall in love with the beauty of the protected areas. They want to make good use of natural resources (资源) but not use them up. For example, they study the animals, the culture and the customs (风俗) or a place so that they can learn more about the history and value (价值) of the area.

In short, “Green Tourism” has a purpose and a plan, but not to pollute our places of interest.

【推荐1】In the past, African penguins laid their eggs in holes dug in their own guano (粪便). But in the 1800s, most of the guano was shipped by traders to the UK, where it was used to make plants grow better. Since then, many penguins have nested in the open, leaving them easy to get heatstroke (中暑). Their eggs are also at risk of being stolen. Shaun Welman, an animal expert, has seen penguins sitting with their eyes closed, heads down and mouths open in the burning midday heat, trying to protect their eggs.

Because penguins evolved (演变) to keep heat in cold water, they can easily overheat on land. Usually, penguins leave their nests regularly to cool off in the sea. But without proper holes, this leaves their eggs unprotected.

“Now the African penguin is on the endangered species (物种) list, mainly because of humans,” Welman says. Since 1900, the African penguin population has dropped from three million to only 48,000.

Luckily, a team of researchers seems to have found a way. Over the past years, the team has put more than 1,500 handmade ceramic (陶瓷的) nest boxes in five areas where the penguins live, including Bird Island in Algoa Bay, South Africa, which is home to nearly half of the world’s remaining African penguins. Looking like small round houses, the double-walled ceramic nests can keep African penguins cool.

The ceramic nests remain around 1°C lower than a penguin’s resting body temperature, which is about 37°C. “The nests are so useful,” Welman says. “Even if adults had to leave nests for some reasons, their eggs would never be at any risk of overheating. In an experiment, the team recorded ground temperatures of nearly 51°C outside a ceramic nest box, while only 23℃ inside.

Welman adds that African penguins, which nest in the open, will be increasingly influenced by their environment as the climate changes.

【推荐3】Many animals are in danger around the world. Here are some examples.