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Nature’s chain reaction 2014.10.21
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Humans share planet Earth with countless species out there, each one closely linked with the other. As biodiversity shrinks, species may disappear one by one, bringing disasters to the world.

About one billion people are suffering from hunger because of climate change, according to a United Nations Intergovernmental Panel on Climate Change report. Millions of families do not even have enough food to survive.

The latest report has taken on a more sombre tone than previous ones, such as that in 2007, which was positive. This report clearly pointed out the serious effect of climate change, including lowering the yield of major food crops such as wheat and maize.

Climate change, as well as human activities such as hunting, deforestation and pollution, is endangering the survival of many species, diminishing biodiversity.

In the early 1990s, more than 100 states signed the Convention on Biological Diversity, which aimed to ensure biodiversity and the sustainable use of natural resources. More than 20 years have passed since the convention became effective, yet there has been clear evidence that our biodiversity remains threatened. If the biodiversity continues to diminish, what consequences will we face?


Broken food chain

ECOLOGISTS have found that in the last 200 years, the number of carnivores has gone down while the number of herbivores has gone up. This has led to streams and rivers to change course, threatening the survival of small animals. The increase in plant-eating animals has also depleted vegetation, and some agricultural land has become barren because of this.

Such changes upset the food chain, and although human beings are at the top of the food chain, we will feel the effect sooner or later.


Food crisis

SOME important food crops species are disappearing. This has happened to some 90 percent of wheat species in China and 1,500 species of rice in Indonesia.

As we lose DNA diversity, it would be hard to find cures if there is an outbreak of crop disease. Massive crop failure would lead to shortage of food.


Infectious diseases

THERE is an intricate relationship between biodiversity and human diseases. When plants and animals become extinct, the variety of food becomes smaller. This would make it more difficult for people to have a balanced diet.

Also, there could be certain elements in the natural environments that are responsible for suppressing pathogens that cause human diseases. Damage to the environment could cause these pathogens to multiply unchecked.


Stop the damage

ECOLOGISTS are warning that the problem of diminishing biodiversity has reached an alarming stage. Some of them even fear that the world is silently moving towards the sixth massive extinction. They said this could be the most devastating extinction event since the asteroid impact that wiped out the dinosaurs.

As a member of the global village, each of us is responsible for the well-being of the Earth, our home. So governments and citizens must join hands to conduct conservation work to arrest the trend of diminishing biodiversity.

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