The Communist Party has made great progress in reducing China’s pollution, but     1     perfect storm of northern winds and an industrial rebound has created dangerously high levels of pollution countrywide.

Sandstorms used     2     (be) a regular occurrence in spring. In previous decades, each May saw at least two rounds of sandstorms, according to state-run Xinhua news agency. The     3     (frequent) and severity of sandstorms was partly due to drought,     4     (grow) population pressure and poor progress in revegetation,     5     caused rapid desertification of land in the north and northwest.     6    , sandstorms have since decreased dramatically. The annual number of sandstorm     7     (impact) days in Beijing fell from a peak of 26 in the 1950s to just three days after 2010, Xinhua reported.

Since 2000, the Chinese government     8    (invest) billions of dollars toward sandstorm prevention. Authorities have launched     9     (variety) reforestation and ecological projects, and installed satellites to monitor sandstorms and alert weather agencies     10     of time.

3 . The fertile land of the Nile delta is being eroded (侵蚀) along Egypt’s Mediterranean coast at an astonishing rate, in some parts estimated at 100 metres per year. In the past, land washed away from the coastline by the currents of the Mediterranean Sea used to be replaced by sediment (沉淀物) brought down to the delta by the River Nile, but this is no longer happening.

Up to now, people have blamed this loss of delta land on the two large Aswan dams in the south of Egypt, which hold back almost all of the sediment that used to flow down the river. Before the dams were built, the Nile flowed freely carrying huge quantities of sediment. But when the Aswan dams were constructed to provide electricity and irrigation, and to protect the huge population centre of Cairo from annual flooding and drought, most of the sediment with its natural fertilizer accumulated up above the dam in the southern upstream half of Lake Nasser, instead of passing down to the della.

Now, however, there turns out to be more to the story. It appears that the sediment-free water picks up sand as it erodes the river bed and banks on the 800-kilometre trip to Cairo. Daniel Jean Stanley of the Smithsonian Institute noticed that water samples taken in Cairo indicated that the river sometimes carries more than 850 grams of sediment per cubic metre of water — almost half of what it carried before the dams were built.

International environmental organizations are beginning to pay closer attention to the region, partly because of the problems of erosion and pollution of the Nile delta, but mainly because they fear the impact this situation could have on the whole Mediterranean coastal ecosystem.

But there are no easy solutions. In the immediate future, Stanley believes that one solution would be to make artificial floods to flush out the delta waterways, in the same way that natural floods did before the construction of the dams. He says, however, that in the long term an alternative process such as desalination (脱盐) may have to be used to increase the amount of water available.

4 . As Plastic Chokes the Ocean, Technology Can Help

Some 8 million tons of non-recyclable (不可回收的) plastic end up in the ocean each year. At an alarming rate, the seas may have more plastic than fish by the middle of the century.     1    

Require a global solution to a global problem.     2     The developed countries and most of developing countries show their leadership in this process by setting goals, encouraging other member states, and offering support for poor countries.

    3     Although they are helpful to protect clean water and air, as it is known, non-recyclable plastic is widely used in the markets. Therefore, non-recyclable plastic still can be bought in our daily life. Its disappearance needs much more time and efforts.

Pay more attention to the new studies on plastic and technologies. Some of researchers are aiming to make replacements for plastic.     4     For example, “interceptors” can remove river pollution before it reaches the ocean.

Expect more responsibility from manufacturers.     5     As a start, they should be encouraged to simplify complex packaging. And their working with world governments will support poorer nations to improve waste collection and landfill (垃圾场) management.

The world doesn’t have enough time in trying to solve the problem. The sooner these efforts start, the better.

5 . The measurable threat to the environment has been worsened by the spread of COVID-19 that increases the need for plastic protective equipment. Most plastic is made from fossil fuels. Millions of tons of greenhouse gas are released from the development of these resources and plastic production and burning.

The end life of plastic is just worrisome. Less than 10% of the plastic produced has been recycled. Even more of it has been burned. But the vast majority of plastic has been buried inland, and it is increasingly polluting the environment. We hear mostly about ocean plastic and the harm done to sea creatures that mistake plastic bags and bits for food. But microplastic is even more worrisome. Plastic doesn't break down biologically but instead breaks down into tiny particles（a very small piece of something）, which have been found in every corner of the planet, on land and in the air, in drinking water and food sources.

Yet the public has not given this global environmental disaster the attention it requires. Instead, they have viewed single-use plastic—which makes up about 40% of plastic used each year—as a litter issue that can be solved through better recycling and waste management. That attitude must change because the recent global breakdown of the market for recycling has made it clear that it has never been, nor ever will be, able to keep up with plastic trash use.

California has been the forerunner of plastic waste reduction—it was the first state to ban single-use plastic bags and may be the first state to transform the way goods are packaged. The state also came close to passing an act which would have required that products sold in plastic packaging in the state have a proven recycling rate of 75% by 2032. California, though influential, can't solve this crisis alone. The US has long been producing a great amount of plastic trash and it should engage in reducing the use of plastic as well.

7 . When Abdus Salam looks across the garbage-filled river near his home in one of the major clothing producing districts in Dhaka, the capital of Bangladesh, he remembers a time before the factories moved in. “When I was young there were no clothing factories here. We used to catch fish in the river,” he said. The river beside him is now black like ink. Waste from nearby clothing factories has polluted the water.

Fashion is responsible for up to one-fifth of industrial water pollution, thanks in part to weak management and enforcement in producer countries like Bangladesh, the world’s second biggest clothing producing country, where wastewater is commonly discharged directly into rivers and streams. The wastewater not only hurts the environment, but pollutes drinking water sources.

Once in waterways, poisonous chemicals from dyes (染料) build up to the point where light is prevented from coming through the surface, reducing plants’ ability to photosynthesize (进行光合作用). This lowers oxygen levels in the water, killing plants and animals. These chemicals and heavy metals can also build up in the body, increasing the risk of serious illnesses and skin problems. What’s worse, chemical-rich water is also used to water crops, with one recent study finding that dyes were present in vegetables and fruit grown aiound Savaz, just north of Dhaka.

Luckily, change is coming. In Bangladesh, there are signs clothing producers are taking environmental responsibility more seriously, with brands committing to initiatives, such as the Partnership for Cleaner Textile, that tackle water, energy and chemical use in the industry. Shahab Uddin of Bangladesh’s Ministry of Environment, Forest and Climate Change said a range of measures were being taken to address pollution, including updating conservation and environmental laws, giving fines to polluters, setting up centralized treatment plants, and working with international development partners to improve wastewater treatment. And under a new environmental policy called Zero Liquid Discharge, dyeing, finishing and washing industries must submit a time-bound plan to reduce, recycle and reuse wastewater.

“There is definitely room for further improvement. These challenges cannot be solved overnight,” Uddin added.