1 . In films and TV shows, police officers study fingerprints to catch bad guys. Now, conservationists (people who work to protect animals and the environment) are using a similar method to deal with the illegal overfishing of sharks.

Overfishing is when too many of a particular type of fish are caught, putting that species in danger. Many sharks are killed because of a high demand — and high price — for their fins. In some countries they are used to make shark fin soup, which some people believe is good for health. Around 100 species of sharks are protected by CITES — the Convention on International Trade in Endangered Species of Wild Fauna and Flora, which is an agreement between 184 countries that protects wildlife that is sold.

CITES has teams of people who visit ports and fish factories to look for evidence of protected species being illegally caught and sold. The idea is to punish those responsible and stop it happening, but finding evidence is difficult and can take a long time. Often, fish are sold before teams arrive and if a fish is cut up ready for sale, it’s hard to tell which species it was.

Scientists have come up with a process that studies “fish dust” — tiny traces of fish that get left on the floor at ports and factories, even after the fish have gone. Using a process called metabarcoding, they examine the DNA in it and can tell if the DNA is from a protected species. The scientists tested the method in Indonesia, where many sharks are caught and sold. They studied dust from seven sites and found evidence of 61 shark species — more than 80% of them CITES-protected. Dr. Andhika Prasetyo, the scientist who led the research, hopes the new method could soon be helping to protect endangered sea life.

2 . In a world with limited land, water and other natural resources, the harm from the traditional business model is on the rise. Actually, the past decades has seen more and more forests disappearing and globe becoming increasingly warm. People now realize that this unhealthy situation must be changed, and that we must be able to develop in sustainable (可持续的) ways. That means growth with low carbon or development of sustainable products. In other words, we should keep the earth healthy while using its supply of natural resources.

Today, sustainable development is a proper trend in many countries. According to a recent study, the global market for low-carbon energy will become three times bigger over the next decades. China, for example, has set its mind on leading that market, hoping to seize chances in the new round of the global energy revolution. It is now trying hard to make full use of wind and solar energy, and is spending a huge amount of money making electric cars and high-speed trains.

In addition, we are seeing great growth in the global markets for sustainable products such as palm oil (棕榈油) , which is produced without cutting down valuable rainforest. In recent years the markets for sustainable products have grown by more than 50%.

Governments can fully develop the potential of these new markets. First, they can set high targets for reducing carbon emissions (排放) and targets for saving and reusing energy. Besides, stronger arrangement of public resources like forests can also help to speed up the development.

Finally, governments can avoid the huge expenses that are taking us in the wrong direction, and redirecting some of those expenses can accelerate the change from traditional model to a sustainable one.

The major challenge of this century is to find ways to meet the needs of growing population within the limits if this single planet. That is no small task, but it offers abundant new chances for sustainable product industries.

Researchers and wetland protectors in Wuhan, Hubei Province, are stepping up efforts to allow more wildlife to survive in their natural habitat.     1     treasured species of ducks is one of the animals benefiting from the growing focus     2     the environment.

In 2012, Baer’s pochard, the blue-headed duck,     3     (list) as critically endangered by the International Union for Conservation of Nature after its numbers declined due to a bad habitat. The ducks were rarely seen in Wuhan until bird-watchers observed     4     (they) living in the city in 2014. Despite that, no proof showed that, so far, the ducks     5     (turn) from migratory birds to resident birds in the city because researchers would not attach tracers to the animals     6     (prevent) humans disturbing them.

In 2019, the Wuhan Bird Watching Society started researching and rescuing the habitats of the duck. They found that the ducks feed on     7     (plant), shrimp and snails. The birds also like to rest in the shallow water     8     food is more than enough.     9     (base) on the results, the team will create an area toward the restoration of the habitat in the city’s Qijiawan for the blue-headed duck, first     10     (discover) in the area.

A small town in England is teaching the world that it is important     1    (grow) your own food. Any open space     2    (use) to grow fruit and vegetables. There are apples, pears, peaches, strawberries, cabbages and carrots, here and there. Everyone can pick them     3     free. Eight years ago, a woman named Pam in Todmorden dug up her rose garden. She planted vegetables, knocked down the garden walls and put up a sign     4    (say), “Help yourself.” Today, Pam has     5    (complete) changed the town. A new town has been born,     6     is called “Incredible Edible Todmorden”. Pam explained why she thought the idea was popular. “It’s possible and positive. Many people know we have to change,     7     how we do that is a question.” So one day, she gathered all the     8    (villager) together. They decided to do something     9    (differ) at once. They didn’t write reports. They didn’t ask for permission. They just did it. Only a short time later, Todmorden　    10    (become) a big garden of fruit and vegetables. In Todmorden, there is a motto: If you eat, you are in. But that’s not all. There are more than 700 edible towns popping up around the world, from Canada to Mali. People there think about food and protect the environment at the same time.

6 . A recent study has found that using wood for construction instead of concrete and steel can reduce emissions. But Tim Searchinger at Princeton University says many of these studies are based on the false foundation that harvesting wood is carbon neutral (碳中和). “Only a small percentage of the wood gets into a timber (木料) product, and a part of that gets into a timber product that can replace concrete and steel in a building,” he says. Efficiencies vary in different countries, but large amounts of a harvested tree are left to be divided into parts, used in short-lived products like paper or burned for energy, all of which generate emissions.

In a report for the World Resources Institute, Searchinger and his colleagues have modelled how using more wood for construction would affect emissions between 2010 and 2050, accounting for the emissions from harvesting the wood. They considered various types of forests and parts of wood going towards construction. They also factored in the emissions savings from replacing concrete and steel.

Under some circumstances, the researchers found significant emissions reductions. But each case required what they considered an unrealistically high portion (一部分) of the wood going towards construction, as well as rapid growth only seen in warmer places, like Brazil. In general, they found a large increase in global demand for wood would probably lead to rising emissions for decades. Accounting for emissions in this way, the researchers reported in a related paper that increasing forest s between 2010 and 2050 would add emissions equal to roughly 10 percent of total annual emissions.

Ali Amiri at Aalto University in Finland says the report’s conclusions about emissions from rising demand are probably correct, but the story is different for wood we already harvest. “Boosting the efficiency of current harvests and using more wood for longer-lived purposes than paper would cut emissions,” he says. “We cannot just say we should stop using wood.”

10 . Molai grew up in a tiny village in India. The village lay near some wetlands which became his second _______. He learned the value and beauty of _______ there from a very young age. 

When he was 16, Molai began to notice something _______ happening around his home. A flood had hit the area earlier that year and the _______ it caused had driven away a number of birds._______, the number of snakes had declined as well. He _______ that it was because there weren’t enough trees to protect them from the _______. The solution, of course, was to plant trees so the animals could seek _______ during the daytime. He turned to the _______ department for help but was told that nothing would grow there. However, Molai went looking on his own and ________ a nearby island where he began to plant trees.

________ young plants in the dry season was ________ for a lone boy. Molai built at the ________ of each sapling (幼树) a bamboo platform, where he placed earthen pots with small holes to ________ rainwater. The water would then drip (滴落) on the plants below.

Molai ________ to plant trees for the next 37 years. His efforts have resulted in 1,360 acres of naturally-grown land that has become home to many plants and animals.