Industrial wastelands to wildlife oases: Five nature wins that have actually worked:

World leaders are gathering in Cali, Colombia, to agree ways to save species from extinction and restore nature. Here are five powerful solutions to halt biodiversity loss.

There's a treasure trove of ways to save species in decline, and restore their habitats so they can live safely. In a healthy state, rich and biodiverse habitats can replenish our water, air, soil and reduce the risk of dangerous contagious diseases.

World leaders will meet at the UN in New York later for more talks to save the world's oceans from overexploitation.

The UN High Seas Treaty has been through 10 years of negotiations but has yet to be signed.

If agreed, it would put 30% of the world's oceans into conservation areas by 2030.

Campaigners hope it will protect marine life from overfishing and other human activities.

Two-thirds of the world's oceans are currently considered international waters, which mean all countries have a right to fish, ship and do research there. But only 1.2% of these high seas, as they are referred to, are protected.

Namibia has one of the world's largest populations of cheetahs

For the first time in 70 years, India's forests will be home to cheetahs.

Eight of them are set to arrive in August from Namibia, home to one of the world's largest populations of the wild cat.

Their return comes decades after India's indigenous population was declared officially extinct in 1952.

The world's fastest land animal, the cheetah can reach speeds of 70 miles (113km) an hour.

Humanity depends on Nature - on habitat for food availablity, pollution control, water purification, and agriculture; on other species for food availability, pollution control and pollination; on the atmospheric and oceanic currents for temperature control and freshwater generation and distribution; on atmosphic layers to protect us from cosmic radiation; and much, much more.

We could never afford to do what Nature does for us - we don't have the capacity or ability, and it would cost us thousands or millions times more than the total wealth of the planet - if we could.

Furthermore, human engineering, rather than replacing Nature, only causes more pollution, which makes the situation worse.

Neither can we find another planet in Space to go live on. We do not know of any other habitable planets, and we do not have the technology to get us there, when we do. Furthermore, this "option" will only be available for a very select few and will be horribly expensive, and won't come before the 22nd century, most likely. Planet Earth and our Human civilization won't survive that long unless we change the way we live dramatically.

The only answer for our Human survival is to reduce and limit our numbers, reduce and limit our development and destruction of the natural world, and reduce and limit our types and amounts of pollution. That is the only way we can save Nature, which we are part of, and upon which we depend absolutely.