Home Science Only 3% of the Earth’s surface has not been ‘plowed’.

Only 3% of the Earth’s surface has not been ‘plowed’.

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Human activities have had a profound effect on the number and abundance of other species.

Oos Lions, hyenas and other predators still stalk the wildebeest, preventing them from eating too much of the plant. The variety of plants and grass supports other species, from fish birds to insects. In turn, these animals carry seeds or pollen throughout the plains, creating conditions for many types of plants to reproduce. Humans also appear there, but with relatively meager density. This is a prime example of an intact ecosystem: complex relationships that together maintain the rich diversity of the Earth. According to a survey of the ecosystems on Earth, most of the land on Earth – about 97% – no longer qualifies for ecological integrity. Researchers announced on April 15 in the journal Frontiers in Forest and Global Change: in the past 500 years, too many species have been either extinct or in decline. Specifically, scientists set the year 1500 AD, which means that only parts of the world are ecologically intact like 500 years ago with the addition of species of similar abundance. can be considered a wilderness. As a result, only 2.8% of planet Earth’s surface matches the description. These “wild plaques”, each with an area of ​​10,000 square kilometers or more, are scattered in various parts of the world. Of the few intact ecosystems, only about 11% of the land is in existing protected areas. These include Nouabale-Ndoki National Park in Congo, Serengeti-Ngorongoro in Tanzania, Alto Rio Negro indigenous territory in the Amazon forest, Great Siberian Polynya in northern Russia, and Kawésqar National Park in southern Chile. These are very rare and special places to be preserved, but only 11% of them are in protected areas. “Those are the best of the best, the last places on Earth have not lost a species as we know it,” said Oscar Venter, a conservation scientist at the University of North British Columbia. . It is important to identify such places, he said, especially for areas under development threats that need protection, such as the Amazon rainforest. Conservation scientists have long tried to map places that have not been affected by human activity. Researchers estimate that 20-40% of the Earth’s soil surface can be considered ecologically intact. But what can be detected by satellite is the ugly reality of the true extent of wildlife habitat. Beneath the seemingly intact tree canopy, the extinction of mammals and large birds from hunting, invasive species or disease has undermined the biodiversity of the areas. wild in the world. Biologist Andrew Plumptre, University of Cambridge said: “Hunting, impact of invasive species, climate change – these can harm ecosystems, but they are not easily detected. right through the satellite ”. Plumptre and his colleagues began looking for habitats that fully retain natural species, in abundance, in 1500 AD. That is the basis that the International Union for Conservation of Nature uses to evaluate the extinction of species, even though humans have changed their ecosystems by wiping out many large mammals over the past thousands of years. Overall, the amount of ecologically intact soil “is much lower than we expected,” said Plumptre. This shows how terribly man has affected nature. Some scientists question whether study authors are too strict in their definition of ecosystem integrity. Many ecosystems around the world have lost one or two species, but they remain vibrant, diverse communities. The decline of some species may not cause a catastrophe to the entire ecosystem, as other species may replace the role of lost species. The researchers calculated that while only 3% of the land is currently ecologically intact, bringing in up to five species lost could restore 20% of the land as before. This helps the ecosystem gradually return to balance.

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