Farming boom hollowing out world’s biodiversity hotspots: Global study

Wild and ecologically rich landscapes across the globe are being rapidly transformed into agricultural land to feed a growing human population — a shift that is exacting a heavy toll on wildlife, especially in some of the planet’s most biologically important regions.

A new global study published on 26 December 2025 in Communications Earth & Environment has found that agricultural expansion inside biodiversity hotspots has led to sharp declines in species diversity and abundance. The findings, reported by Down To Earth, underline the growing tension between food security and ecological survival.

The research was led by scientists from the Chinese Academy of Sciences and China Agricultural University, with collaborators from the University of Cambridge, the University of Maryland and the University of Oklahoma.

The authors warned that conservation efforts must urgently prioritise biodiversity hotspots, where agricultural pressure is rising faster than anywhere else.

Biodiversity hotspots are regions that harbour an exceptional variety of plant and animal life, much of it found nowhere else on Earth. Though biologically rich, these areas are already severely degraded — having lost more than 70 per cent of their original natural vegetation. What remains of their unique biodiversity is now confined to increasingly fragmented and shrinking habitat patches, making their protection critical to preventing mass extinctions.

As Down To Earth has previously reported, these hotspots are facing mounting pressure from farms, cities and infrastructure projects, with land-use change emerging as one of the leading drivers of biodiversity loss worldwide.

The new study focused on small-ranged vertebrates — including mammals, birds and amphibians — whose distributions are limited to narrow geographic zones. Such species are especially vulnerable because even modest habitat loss can wipe out entire populations.

Many of these animals play essential ecological roles such as pollination, seed dispersal and pest control. Their decline can therefore trigger cascading disruptions that destabilise entire ecosystems.

Researchers found that farming within biodiversity hotspots has caused a 26 per cent drop in species richness, meaning croplands support far fewer species than the natural habitats they replace. There was also a substantial fall in the total number of individual animals and plants.

At the same time, agriculture is expanding most aggressively in tropical regions close to the equator — areas that also tend to host the highest biodiversity.

Compounding the problem, the study found that much of the wildlife in biodiversity hotspots exists outside formally protected parks and reserves. These unprotected landscapes are far more vulnerable to conversion for farming, further squeezing already rare and endemic species.

To assess the impact of agriculture, the researchers analysed wildlife survey data from the global PREDICTS database, comparing intact forests and grasslands with areas converted to farmland. They examined three indicators: the number of species present, the total abundance of individuals, and community diversity adjusted for population size.

The results were stark. In hotspot areas converted to farmland, species richness fell by 26 per cent, total abundance by 12 per cent, and community diversity by nearly 9 per cent compared to natural habitats.

Using high-resolution satellite imagery, the researchers also tracked cropland expansion between 2000 and 2019. Cropland within biodiversity hotspots grew by 12 per cent during this period — significantly faster than the global average of 9 per cent.

This expansion was particularly pronounced in regions such as the Cerrado and Atlantic Forest in South America, Indo-Burma and Sundaland in Southeast Asia, and parts of eastern and southern Africa, Down To Earth reported.

By overlaying cropland expansion maps with the distribution of small-ranged vertebrates, the study identified 3,483 high-risk zones across global biodiversity hotspots, covering about 1,741 million hectares. Alarmingly, nearly 1,031 million hectares of these zones lie outside protected areas.

India’s Western Ghats under pressure

The global patterns highlighted in the study are playing out sharply in India’s Western Ghats — one of the world’s most critical biodiversity hotspots. Reporting from the region, Down To Earth spoke to Akshay Gawade of the Applied Environmental Research Foundation (AERF), Pune, who said land-use change is accelerating rapidly.

Large tracts of the northern Western Ghats are being converted into orchards, driven in part by government subsidies. “Traditional farming systems are breaking down,” Gawade said. “As younger generations move out, land is often sold to orchard owners or wood loggers. This is changing land-use patterns very quickly.”

Unlike industrial monoculture farming, agricultural expansion in the Western Ghats often takes the form of plantations and mixed-use farms. But these still fragment natural habitats into smaller, disconnected patches, making it harder for wildlife to move, breed and survive.

This poses serious risks for a region that supports over 5,000 flowering plant species, 139 mammals, 508 birds and at least 325 globally threatened species — many of them, especially amphibians and plants, found nowhere else.

Research has already documented these impacts. A study by researcher Vijayan Jithin found that when rocky plateau ecosystems in Maharashtra’s northern Western Ghats were converted into rice paddies and orchards, amphibian diversity declined dramatically.

The International Union for Conservation of Nature has also flagged the Western Ghats as being of “significant concern” in its 2025 World Heritage Outlook 4 report, citing land-use change and development pressures. The assessment drew on inputs from state forest departments and recommendations from the Western Ghats ecology expert panel.

Protecting biodiversity in such landscapes is particularly challenging because, unlike national parks, privately owned farms and plantations are difficult to regulate amid strong economic and political pressures.

Although the global study does not directly analyse plantation systems, its findings reinforce the risks of continued land conversion in biodiversity-rich regions, regardless of how agriculture is structured.

The authors argued that simply expanding farmland to meet rising food demand is not a viable strategy in biodiversity hotspots. Instead, they called for a combination of measures: strategically expanding protected areas where rare, small-ranged species are concentrated; strengthening enforcement within existing reserves; improving productivity on already cultivated land to reduce pressure for further clearing; and increasing international cooperation on food trade so biodiversity-rich but poorer countries are not forced to degrade ecosystems to feed wealthier nations.

Crucially, they also stressed the need to involve local communities in conservation and monitoring, recognising that people living in these landscapes must be part of any lasting solution.