Sell sand and talk about it.

20 19 September, a South African entrepreneur was shot dead. In August, two Indian villagers died in a gun battle. In June, a Mexican environmentalist was murdered. Although thousands of miles apart, they are all the latest victims of the growing wave of violence. The cause is one of the most important but least concerned commodities in 2 1 century: ordinary sand. Sand seems insignificant, but it is an important part of our life. It is the main raw material of modern cities. The concrete used to build shopping centers, office buildings and apartment buildings, and the asphalt we use to build roads are basically made of sand and gravel. Every window, windshield and glass on the smartphone screen are made of melted sand. Even the silicon chips in our mobile phones and computers, as well as almost all other electronic equipment in our home, are made of sand. Our planet is covered with sand. From the Sahara desert to the Arizona desert, there are rolling dunes. The beaches along the coastline all over the world are covered with sand. We can even buy some bags of sand at the local hardware store with a little change. But believe it or not, the world is facing a shortage of sand. Apart from water, sand is the most consumed natural resource on earth. Humans use about 50 billion tons every year? Polymerization? (? Gravel? Industry jargon), which is enough to cover the whole of Britain.

The problem lies in the type of sand we use. The sand in the desert is basically useless to us. Most of the sand we harvest is used to make concrete, so the shape of desert sand is wrong. They are too smooth and round to combine to form stable concrete due to wind erosion rather than water erosion.

The sand we need is angular things found in river beds, river banks, flood plains, lakes and coasts. The demand for this material is so great that all over the world, people strip riverbeds and beaches and destroy farmland and forests to obtain precious sand. In more and more countries, criminal gangs began to set foot in this industry, which gave birth to a deadly sand black market.

Urbanization has aggravated the problem of sandstorm.

Pascal, a researcher at the United Nations Environment Programme? Peduzzi said? The problem of sand surprises many people, but it shouldn't be like this. We can't extract 50 billion tons of anything every year if it doesn't have a great impact on the earth and people's lives. ?

The main driving force of this crisis is dangerous urbanization. Every year, more and more people on earth move from rural areas to cities, especially in developing countries. In Asia, Africa and Latin America, cities are expanding at an unprecedented speed and scale in human history.

Since 1950, the population living in urban areas has more than tripled, and now it is about 4.2 billion. The United Nations predicts that 2.5 billion people will join the urban population in the next 30 years. This is equivalent to adding eight cities the size of new york every year.

It takes a lot of sand to build buildings to accommodate all these people and to build roads to weave them together. In India, since 2000, the amount of sand and gravel used for construction has increased by more than three times every year, and it is still growing rapidly. In the whole decade, China alone may have used more sand than the United States used in the whole 20th century. The demand for some types of building sand is so great that Dubai, located on the edge of the huge desert, has to import sand from Australia, so Australian exporters are actually selling sand to Arabs. However, sand is not only used for buildings and infrastructure, but also increasingly used to make the land under your feet. From California to Hong Kong, bigger and more powerful dredgers suck millions of tons of sand from the seabed every year and pile it up in coastal areas to build land that never existed before. Palm Island in Dubai may be the most famous man-made land built from scratch in recent years, but they have many companions.

Lagos, Nigeria's largest city, is expanding 9.7 square kilometers to its Atlantic coastline. China is the fourth largest country on earth, its coastline has increased by hundreds of miles, and an entire island has been built to accommodate luxury resorts.

The high price paid for dredging sand

This new real estate is valuable, but its price is often high. Marine dredging has damaged coral reefs in Kenya, the Persian Gulf and Florida. It destroys marine habitats and makes the waters with dust plumes turbid, thus affecting aquatic life far away from the original site. Fishermen in Malaysia and Cambodia found that their livelihood was lost due to dredging. In China, land reclamation has destroyed coastal wetlands, destroyed the habitats of fish and waterfowl, and aggravated water pollution.

There is also Singapore, which is a world leader in land reclamation. In order to create more space for nearly 6 million residents, this crowded city-state has increased 130 square kilometers of land in the past 40 years, almost all of which are paved with sand imported from other countries. The collateral environmental damage is so serious that neighboring Indonesia, Malaysia, Vietnam and Cambodia all restrict the export of sand to Singapore.

According to the statistics of a Dutch research group, since 1985, human beings have increased 13563 square kilometers of artificial land in the coastal areas of the world, which is equivalent to the land area of Jamaica. Most of them are made of a lot of sand.

Sand mining for concrete and other industrial purposes is more destructive. Construction sand is usually mined from rivers. Sand can be easily pulled up with a pump or even a bucket, and once it is full, it is easy to transport. But dredging the riverbed will destroy the habitat occupied by benthos. Agitated sediments will make the water turbid, suffocate the fish and block the sunlight needed to maintain the growth of underwater vegetation.

River sand mining has also led to the slow disappearance of the Mekong Delta in Vietnam. This area is the home of 20 million people, the source of half of the country's food, and the supplier of most rice in other parts of Southeast Asia. The sea level rise caused by climate change is one of the reasons why the delta loses an area equivalent to one and a half football fields every day. But researchers believe that another reason is that people are plundering the sand in the delta.

For centuries, the sediments brought by the Mekong River from the mountains of Central Asia have supplemented the delta. But in recent years, in various countries along the way, miners have begun to pull a lot of sand from the riverbed. According to a study conducted by three French researchers in 20 13, these miners mined about 50 million tons of sand in 20 1 1 year, which was enough to cover the depth of 5 cm in Denver. Meanwhile, in recent years, five dams have been built on the Mekong River, and another 65,438+02 dams are planned in China, Laos and Cambodia. The dam further reduces the sediment flow to the delta.

In other words, although the natural erosion of the delta continues, its natural recharge has not continued. WWF？ Greater Mekong project? Some researchers believe that at this rate, nearly half of the delta will disappear by the end of this century.

To make matters worse, in Cambodia and Laos, dredging the Mekong River and other waterways is causing banks to collapse, destroying farmland and even houses. Farmers in Myanmar revealed that the same thing happened along the Irrawaddy River.

Sand mining from rivers has also caused millions of dollars in damage to infrastructure around the world. The stirred sediment blocked the water supply equipment. Dig all these materials away from the river bank, and the foundation of the bridge will be exposed without support. In Ghana, sand diggers dig too much ground, which exposes the building foundation on the hillside to danger and threatens to collapse at any time. Not just a theoretical risk. In 2000, a bridge in Taiwan Province Province collapsed due to sand mining. The following year, a bridge in Portugal collapsed when a bus passed by, killing 70 people.

The darkness and sin behind the sand

The demand for high-purity silica sand is also surging. Silica sand is used to make glass and high-tech products, such as solar panels and computer chips. America's prosperity? Hydraulic fracturing industry? You also need ultra-durable high-purity silica sand. This has led to the destruction of large areas of farmland and forests in rural Wisconsin, and these places happen to have a lot of precious sand.

The competition for sand has become so fierce that in many places, criminal gangs have begun to set foot in this industry, and the excavated sand is sold on the black market. Human rights organizations say that in parts of Latin America and Africa, children are forced to be slaves in sandpits. Like organized crime elsewhere, these criminal gangs evade punishment by bribing corrupt police and government officials. When they think it is necessary, they will attack or even kill people who hinder their actions.

Jose? Louis? Alvarez? Flores is an environmental activist in Chiapas, southern Mexico. He was shot for opposing illegal sand mining in a local river. It is reported that a note threatening his family and other environmentalists was found on him. Two months later, police in Rajasthan, India, were shot while trying to stop a tractor full of illegally mined sand. The ensuing gun battle resulted in the death of two miners and the hospitalization of two policemen. Earlier this year, a sand miner in South Africa was shot seven times in a dispute with another group of miners.

These are just the latest casualties. In recent years, violence related to sand trade has claimed many lives in Kenya, Gambia and Indonesia. In India, the local media call it? Sand mafia? , causing hundreds of injuries and dozens of deaths. The victims included an 8 1 year-old teacher and a 22-year-old activist who were hacked to death, a journalist who was burned to death and at least three policemen who were run over by a sand truck.

People are more and more aware of the dangers of relying on sand. Many scientists are studying to replace sand in concrete with other materials, including fly ash left by coal-fired power plants, plastic fragments, and even crushed oil palm shells and rice husks. Other companies are developing concrete that needs less sand, and researchers are looking for more effective ways to grind and recycle concrete.

In many western countries, river sand mining has been basically eliminated. However, it is difficult for other parts of the world to follow suit. A report on the global sand industry recently released by the World Wide Fund for Nature (WWF) said: In order to prevent or reduce the possible damage to rivers, the construction industry must stop using Heyuan aggregate. This kind of social transformation is similar to the social transformation needed to cope with climate change, which will force people to change their understanding of sand and rivers and change the design and construction of cities. ?

University of Colorado coastal geographer Mette? More and more scholars call on the United Nations and the World Trade Organization to take more measures to limit the damage caused by sand mining, and bendiksen is one of them. ? We should have a monitoring plan. Bendiksen said,? Because there is no management at present, more management is needed. ?

At present, no one even knows how much sand has been dug out of the ground, and no one knows where and under what conditions, most of which are illegal. Bendiksen said,? We know that the more people there are, the more sand we need. ?

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