Over the past century, the planet has undergone dramatic changes for the worse. The number of people, which in 1900 was less than 2 billion, doubled and then doubled again to almost 8 billion today. At the same time, more and more virgin land has been converted to artificial uses: agriculture, infrastructure, housing.
Wildlife habitats have been decimated. The forests have been cut down. The coastal areas have been rebuilt. However, all is not yet lost.
An international team of researchers from the National Geographic Society and the University of California has mapped the Earth for our collective footprint in areas of ice-free land to see how much has escaped being used for anthropogenic uses.
They estimate that roughly half of the earth's land areas (somewhere between 48% and 56%) have not been affected by us. Three out of four spatial assessments conducted by scientists have found that almost half of the non-permanent land covered in ice or snow has had little human influence, especially in areas with cold climates such as large parts of Canada and Siberia in Russia. .
That sounds like good news, but they caution in their recently published study that “much of the very low-influence parts of the planet are comprised of cold landscapes (eg, boreal forests, mountain grasslands, and tundra) or arid (p . Eg, Deserts). Only four biomes (boreal forests, deserts, temperate coniferous forests and tundra) have the most data sets that agree that at least half of their area has very low human influence.
Those most affected have been temperate grasslands, tropical coniferous forests, and tropical dry forests, of which only 1% have been largely unaffected by humans. Tropical grasslands and mangroves have fared just as badly. This is especially puzzling as these areas have been among the most biodiverse on the planet.
Overall, half of the Earth's land area has had relatively low human influence, "offering opportunities for proactive conservation actions to retain the last intact ecosystems on the planet," the experts write. However, they add, "although the relative abundance of ecosystem areas with low human influence varies widely by biome, keeping these latter areas intact should be a high priority before they are completely lost."
Today, about 15% of the planet's land surface is protected in some way, as are about 10% of its oceans. Conservationists have called for doubling the size of land-based protected areas by 2030. They would also like to see half of the oceans protected by mid-century to ensure that the planet's remaining ecosystems can still thrive.
"If we act swiftly and decisively, there is a thin window in which we can still preserve roughly half of the earth in a relatively intact state," said lead study author Jason Riggio, an academic at the Museum of Fish and Wildlife Biology in the University of California at Davis.