By Tim Radford
Nature concentrates its riches in selected spots. Save those natural hotspots, and you could save biodiversity. Really?
Nations that signed up to preserve biodiversity − the richness of living things in the world’s forests, grasslands and wetlands − are not doing so very well: in one generation they have altered, degraded or cleared at least 1.48 million square kilometres of natural hotspots unusually rich in wildlife.
This is an area in total larger than South Africa, or Peru. It is almost as large as Mongolia. And importantly, this lost landscape adds up to 6% of the scattered ecosystems that make up the world’s biodiversity hotspots.
The biodiversity hotspot was defined, in 2000, as an area of land home to at least 0.5% of the world’s endemic species of plant. That means that a tract of marsh, savannah, upland or forest that may have already lost 70% of its cover is host to at least 1500 species native to that landscape and nowhere else.
Researchers at the time calculated that 44% of all vascular plants and 35% of all amphibians, reptiles, birds and mammals could be concentrated in just 25 such hotspots on the world’s continents and islands.
The hotspot count has since been increased to 34. But the message has remained. Focus on preserving and protecting these areas and you have a “silver bullet” strategy for conserving wildlife worldwide.
First such inventory
But, say scientists in the journal Frontiers in Ecology and the Environment, between 1992 and 2015 much of this precious wilderness has been consumed by agriculture, or paved by sprawling cities.
Their analysis of high resolution land-cover maps made by the European Space Agency is the first to try to look at the global inventory of hotspots, over a time frame of almost a quarter century.
“We see that not even focusing protection on a small range of areas worked well,” said Francesco Cherubini of the Norwegian University of Science and Technology, who with colleagues carried out the research. “There was major deforestation even in areas that were supposed to be protected.”
Two fifths of the lost landscapes were in forests, and agriculture accounted for most of this loss, particularly in the tropical forests of Indonesia, the Indo-Burma region and Mesoamerica. Five per cent of the lost hotspots were in areas formally declared as under state protection.
“The soils in these areas are very fertile, and agricultural yields can be very high. So it’s very productive land from an agricultural point of view, and attractive to farmers and local authorities that have to think about rising local incomes by feeding a growing population,” Professor Cherubini said.
“Not even focusing protection on a small range of areas worked well … There was major deforestation even in areas that were supposed to be protected.”
But most of the lost land went not to feeding people: it went instead to producing palm oil or soybeans for cattle feed. And local people may not have benefited: the change was driven by commercial agribusiness.
“You have these big companies that are making these investments, with high risks of land overexploitation and environmental degradation. The local population might get some benefits from revenues, but not much.”
The tension between hungry humans and vulnerable wilderness continues. Once again, such research supports a call for the people of the planet to consider a switch to plant-based diets, a switch that could contain climate change and preserve the natural capital on which all life depends. But many of those rich habitats are in some of the poorest countries.
“We need to be able somehow to link protection to poverty alleviation, because most of the biodiversity hotspots are in underdeveloped countries and it’s difficult to go there and say to a farmer, ‘Well, you need to keep this forest − don’t have a rice paddy or a field to feed your family’”, Professor Cherubini said.
“We need to also make it possible for the local communities to benefit from protection measures. They need income, too.” − Climate News Network