Humans have only a decade to take drastic actions and avert what some scientists describe as the Earth’s sixth mass extinction, the United Nations has warned.

It says that protecting the planet’s biodiversity, which includes all plant and animal life, could decide humanity’s survival.

The report, released by the UN Convention on Biological Diversity in January, says that Earth’s biodiversity has been “deteriorating worldwide” over the past decades because of pollution and urban encroachment. The trend is expected to worsen, which it says will pose a significant threat to man’s well-being.

To reverse biodiversity decline, “transformative changes”, including cutting pollution levels by half and protecting at least 30 per cent of our land and sea, will need to be achieved by 2030, it says.

Natural disasters which have been intensified by climate change, such as rampant bushfires, frequent flooding and stronger typhoons, have taken a toll on some 8.7 million species and organisms that exist on the planet.

Scientists say that a high-level of biodiversity ensures the functioning of Earth’s ecosystem, and is crucial for providing much-needed water, food, and medicine for humans.

Since the end of 2019, Australia’s bushfires have wreaked havoc across the country, killing dozens of people and destroying entire towns in the suburbs.

Scientists estimate that more than one billion animals have been killed by the inferno, and the very existence of many species, including native koalas, have become threatened.

Floods in India, which struck northern parts of the country in July, killed more than 100 people and significantly damaged one of the country’s best-known national parks, Kaziranga National Park, which is also a Unesco World Heritage site.

Park officials say that more than 200 animals in the park, such as rhinos, elephants and hog deers, were killed because their habitat was left submerged by torrential rain.

Human activity is also a major cause of habitat loss. According to the global conservation group WWF, more than 170,000 square km (65,600 square miles) of forests and woodlands disappear annually owing to agricultural activities.

Pollution and rapid urbanisation have also undermined habitat in both land and sea. In the ocean, some 100 million metric tonnes of aquatic life are taken for food each year.

How much is a metric tonne?

This has caused significant effects on wildlife – figures from the International Union for Conservation of Nature (IUCN) show that about 2,000 mammals have suffered the consequences.

The affected species include the blue whale, the largest animal known to have existed. According to the IUCN Red List, which records creatures whose existence is under threat, the blue whale is endangered because of over-hunting and habitat shifts.

Fortunately, conservation efforts have helped reduce the threat to some other species, including the humpback whale, which as recently as 1988 was listed as endangered. Its current status is listed by the WWF as “least concern”.

Black or grey humpback whales – which can reach up to 15 metres long and get their name from the distinctive hump in front of their small dorsal fin – were widely hunted by man from the 17th century up to the early 20th century.

The good news is, the WWF says the population of humpback whales has now recovered after all International Whaling Commission members agreed to a hunting moratorium in 1986 to allow whale numbers to recover. They are still hunted in a few places, including Greenland and Japan, which has now withdrawn from the IWC and – despite criticism – resumed commercial whaling last summer.

Biodiversity includes all ecosystems and life on Earth. However, it is not evenly spread across our planet. The richest source of land biodiversity is in the tropics.

Tropical forests cover less than 10 per cent of the Earth’s surface, yet contain 90 per cent of the world’s species.

The great hornbill, a bird native to Southeast Asia, is threatened with a decreasing population because of the loss of forest areas.

The same is true for marine biodiversity. The marine environment is far more diverse than that found on land. Thirty-two out of the 33 described animal phyla are represented there, according to WWF.

Cost of biodiversity loss

Biodiversity loss can cause detrimental effects on human beings, as we depend on it for the air we breathe, the water we drink and the food we eat.

According to the World Health Organisation, biodiversity loss can affect the functioning of ecosystems and result in health consequences. This is because biodiversity plays a crucial role in world food production through ensuring soil productivity and providing genetic resources for crops and livestock that humans harvest for food.

Its loss can have an adverse impact on the nutritional value of food, which in turn affects human health.

A study conducted by American researchers has also found that a high level of biodiversity loss could undermine plant growth at similar rates as other drivers of environmental change, such as ozone pollution and acid rain, the United States National Science Foundation says.

This means that biodiversity loss could significantly reduce nature’s ability to provide food, clean water and a stable climate needed for man’s survival.

Sustainable biodiversity is particularly important for developing countries, as wild animals are a critical source of food for the world’s poorest population, WWF says.

Biodiversity loss also has economic consequences. In Europe alone, the continent has annually lost about 3 per cent of its gross domestic product (GDP), or €450 million (US$500 million), owing to biodiversity loss, according to estimates from advocacy group Global Humanitarian Forum.

Biodiversity loss also affects us in other ways. For example, new cancer-fighting drugs are harvested from fungi that grow on the fur of sloths, while many industrial materials are derived from biological sources such as fibres, dyes, rubber and oil.

Money talks

If the value of our ecosystem can be measured monetarily, it can potentially be worth trillions of US dollars. Renowned American ecological economist Robert Constanza and his researchers valued the world’s ecosystem services at US$142.7 trillion in 2014.

According to the World Bank, the world’s top 15 economies represent 75 per cent of the total global GDP, which in 2018 was worth US$85.8 trillion.

Latest statistics show the world’s richest economy, the United States, has a GDP valued at US$21 trillion.