Coral reefs (珊瑚礁) are a unique ocean ecosystem consisting of rocky structures mainly formed by coral animals and some other ocean life. Despite only covering 0. 2 percent of the ocean floor, coral reefs support at least 25 percent of marine species, as well as providing food and economic security for hundreds of millions of people.

However, coral reefs across the world are under threat. Warmer oceans can cause the coral bleaching (漂白). It happens when the corals lose colored algae (海藻) living in their bodies and turn completely white. Without the algae, the corals lose their main food source and can die. In addition, as oceans become more acidic (酸性的) from absorbing CO2, corals in acidic conditions become weak in forming reefs.

In 2021, the United Nations reported a 14 percent loss of corals across the world largely from rising sea temperatures in the previous 13 years. Australia declared mass bleaching events in 2022 across large parts of the Great Barrier Reef, four times since 2016. Data from the Philippines showed higher than usual ocean temperatures between 2015 and 2017 had caused a serious three-year bleaching events in reefs across the planet.

Scientists have been cooperating to see how coral reefs can be protected. Thankfully, they find those coral reefs in the hot parts of the globe are the worst affected. They contain corals with better heat resistance. So their research focus on finding genes (基因) for heat tolerance so that they can be passed on to future generations. Biologists also mix corals that are more resilient to higher temperatures with those that are not and the resulting generation has a better chance of survival.

Ultimately, scientists add that without a serious reduction in greenhouse gas, 99 percent of the world’s coral reefs will be gone by the end of the century. There is a limit to how quickly corals can adapt warm climate, but if temperatures rise rapidly, then extinction is certain.

We all agree that we should recycle more at home, in the office or when out and about. 【小题1】 As a result, they can be collected and taken to the right place for recycling. This is what the process of sorting allows us to do.

【小题2】 And the effective sorting needs to happen first in our own home, and second in sorting plants to which waste is collected. When you put a plastic bottle in the right recycling bag or bin, you are helping sort recyclable things so that the right material can be fed into the right recycling process. If sorting does not happen, a lot of recyclable materials can end up in landfills. It will lead to valuable resources lost from our economy.

【小题3】 For instance, in Brussels consumers put plastic packaging, cans and soft drink cartons in blue bags designed for recyclable packaging; paper in yellow bags for recycling; and glass needs to be taken to specific collection bins. Somewhat differently, in Vienna(Austria), citizens can expect their paper, metal, glass and plastic to be separately collected in different weeks of the year. 【小题4】.

Once recyclable materials are collected from your home, they are further sorted in specialized facilities which ensure the quality of the recycling process. 【小题5】 Traditionally, sorting has been done either by hand with workers sorting what can be recycled and picking out the materials to be thrown away. Today, however, new sorting technologies are being developed in order to speed up the process of sorting but to also cause better results. Exciting technologies using magnets or optical systems are being used to effectively sort materials so more of them can be recycled.

Over the past decade, drug-resistant (抗药性) diseases have appeared as a major health threat. But where do they develop the drug resistance? One surprising theory: they may have developed the resistance on farms, and not in hospitals.

The crop protection products farmers use to control many plant diseases are almost the same as the drugs doctors use to treat infections, including fungi (真菌). Fungi are continually mutating (变异), and with a life cycle measured in days or weeks, they mutate quickly. When a mutation produces resistance to a chemical–killing fungi, fungi will jump to any host that provides a welcoming environment, such as a human body. And if the treatment for the fungal infection involves a drug similar to the fungicide (杀菌剂) met on the farm, fungi may develop quickly in the human body—just as they did in the field.

An obvious solution is to use less fungicide in the field. Reducing fungicide use would not only slow the development of the drug resistance, but it would also help restore diversity to the fungal world. Fungicides are a must in the farming community. Plant diseases cause a major problem for farmers globally—in some crops, disease can reduce harvests by more than 70 percent—and failure to deal with the problem can mean financial ruin.

Just like fungi—or, indeed, any living thing—plants continually evolve(进化). This is how natural gene editing (基因编辑) works, and without it, we’d all still be single cells in a salty soup. Through natural selection, almost any plant will eventually produce resistance to fungi. But this can take centuries, so we don’t have the time to wait.

On the other hand, advances in genetics have given us an understanding of nature’s gene editing process in plants, helping us develop resistance to a disease. Gene editing techniques can then enable us to produce disease resistance－just as nature would do, if given enough time.