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.

It was once a shoreline buried by enough garbage to make it invisible (看不见的), thus, given the unfortunate nickname "toilet bowl" . Now the Philippines' Manila Bay beach is totally different, compared with a few months ago. It happened so suddenly and extremely that it brought tears to the eyes of the local people.

The cleanup started on 27 January, when 5, 000 volunteers descended on Manila Bay to remove over 45 tons (公吨) of garbage, marking the beginning of a nation-wide environmental campaign. But some two months before this great movement began, a quiet revolution was already underway.

During the first week of December 2018, Brooklyn- based Bounties Network collected three tons of garbage from Manila Bay every two days through a project that paid a small group of people, mostly fishermen, with a digital currency (数字货币) based on the Ethereum system.

For the mostly non-bank -using Filipino fishermen, this was a first-ever experience with a digital currency. It's one that proves decisive in enabling poor communities around the world to take up arms in the fight against humanity's waste.

There are signs that this recycling-for-digital payment industry may be just about to take off. Earlier in September 2018, Plastic Bank, a Vancouver -based company powered by IBM technology, also started a similar project. They set up a project in Naga, a town in southern Luzon, the country's largest island, building a collection point to let people exchange plastic and recyclable materials for digital payouts through a system.

That both these pioneers have chosen the Philippines as their first location is not surprising considering the country's contribution to ocean waste. A Wall Street Journal study in 2015 revealed that the Philippines make the third-largest amount of plastic waste into global oceans.

Among the world’s waste-recycling pioneers, Germany is the leader. The country has quite a detailed way of sorting their waste-down to the color of glass waste, the type of paper, the separate bin for metals, etc.

Here below are what you should know about Germany’s waste sorting system：

◇You are expected to gather your waste in your apartment/housing area’s local public garbage bins.

◇There are commonly several types of public garbage bins available in the German’s apartment/housing areas：

Blue bin — for paper and cardboard

Green and white bin — for glass, different bins for differently colored glass, not available for holiday decorations and lights

Yellow/orange bin — for plastic and metals

Brown bin — for goods that can be changed naturally by bacteria into substances that don’t harm the environment, like leftovers, fruit and vegetables

Gray/black bin — for everything else that can’t be recycled such as used cat litter and animal waste

◇Some items don’t belong in these public garbage bins. Items like used batteries, electronics, unused paints, and lights must be returned to the special agent/locations so they can be properly recycled. Other items such as clothes, shoes, and oversized rubbish and furniture are advised to be donated or sold.

◇There’s this thing called Pfand in Germany, a certain part of the price for a bottled drink that you get back if you send back the bottle to certified (有资历的) shops. German law requires shops over a certain size selling bottled drinks have a Pfandruckgabestelle, or place for bottles with deposits (押金). These bottles usually made of glass or plastic will be refilled. Of course, there’re strict health regulations.