An international study led by researchers from the University of Queensland (UQ) has found that many parts of the planet are still impacted by habitat destruction due to human activity.
According to the research, published this week in the journal Conservation Letters, recent decades have seen an uptick in the establishment of protected areas, however the historical rate at which humans have taken over means there are regions around the world where we risk losing biodiversity forever.
The research team, led by James Watson from UQ, has asserted that more than half of Earth’s land can be classified as completely converted to human use.
“An area of 4.5 million square kilometres, or about two thirds the size of Australia, has been converted to human-dominated land use in the past two decades alone,” said Watson.
The researchers focused on ‘habitats’—any place in nature where the plant and animal life hasn’t been significantly altered by humans, leaving the local ecosystem pretty much intact. Through agriculture, industrial logging, as well as building human settlements and cities, land becomes permanently converted for human use.
As part of the study, scientists calculated the ratio of habitat protection versus conversion across 825 land ecoregions—geographically distinct habitats—between 1993 and 2009. They found that habitat loss at 10% or more took place in 91 ecoregions.
“The vast majority of ecoregions have very high levels of habitat conversion compared to their overall areal protection,” the authors wrote.
"We've cleared half the planet already. We don't need to clear any more land”
Habitat loss affects biodiversity, being one of the main drivers of species extinction—but it’s not just protection of wildlife that makes it relevant, because ecosystems also sustain humans, especially in developing areas.
“The most vulnerable people on Earth, the bottom billion, rely entirely on the services of nature,” explained Watson. “When you degrade nature, you have huge impacts on those ecological and evolutionary services that help people survive, and in the long term it means that humanity suffers."
The researchers are saying that the current land conversion practices need to stop.
"Let's be clear - we've cleared half the planet already. We don't need to clear any more land,” Watson said. “Through current farming regimes we produce more than enough food for the planet, but we're very greedy and we don't share that food around, and our trading practices mean that certain countries have more food than others.”
Watson believes that trade policies need to be altered globally to allow for an equitable distribution of food “across all nations.”
"Our farming practices are getting far more efficient, we're creating more and more food on the same plots of land, which means that we don't need to clear out more," he said.
According to Watson, this is especially true for rich developed nations such as United States and Australia where habitats are still being cleared at a startling pace, instead of focussing on land management and sustainable living in urban areas where the land has already been claimed by humans.
“[Rich countries] should be environmental leaders and they should be actually enabling poorer countries to develop in more sustainable ways."