Grasslands and wetlands are disappearing under the plow at nearly four times the rate of forests, according to a peer-reviewed study published in the Proceedings of the National Academy of Sciences on March 3, 2026. The finding challenges the longstanding assumption that deforestation is the primary front in the battle against agricultural land conversion. Between 2000 and 2020, somewhere between 173 and 243 million hectares of non-forest ecosystems were converted to cropland globally, dwarfing the 18 to 173 million hectares of forest lost to the same cause over the same period.
The Numbers Behind the Disparity
The gap between forest and non-forest conversion is not a rounding error. Researchers found that the conversion rate of natural non-forest ecosystems was nearly four times that of lands with tree cover exceeding 5%, a ratio that held across a 15-year analytical window from 2005 to 2020 as global demand for meat, cereals, nuts, and oilseeds accelerated. The team relied on multiple 30-meter-resolution global land-cover datasets to cross-check those results, using overlapping time series to reduce errors and reconcile differing land classifications.
The range of non-forest conversion, 173 to 243 million hectares, reflects the way different mapping products interpret mixed landscapes, but the trend line is consistent. One of the core datasets, derived from high-resolution land-cover analysis, was paired with other global products to bracket uncertainty. Even at the upper bound of forest conversion, 173 million hectares, non-forest losses still match or exceed forest clearing, and at the lower bound they overwhelm it. This reframes agricultural expansion as a broader habitat issue rather than a problem confined to tree-covered regions.
Methodologically, the researchers followed an approach similar to earlier regional land-use studies, combining satellite imagery with change-detection algorithms and post-classification checks. That allowed them to distinguish new cropland from existing fields, and to separate natural grasslands and wetlands from managed pastures or already-degraded land. The resulting maps show a patchwork of encroachment that rarely appears in national statistics, where small, dispersed losses are easy to overlook.
Why Forests Dominate the Conversation
Forests have long claimed the center of conservation attention, and for understandable reasons. They are visually dramatic, home to charismatic species, and central to carbon sequestration narratives that drive international climate policy. Grasslands and shrublands, by contrast, lack that same cultural resonance. A treeless prairie does not trigger the same alarm as a burning rainforest, even when its ecological value per hectare may be comparable in terms of biodiversity, soil carbon, and water regulation.
That perception gap has real policy consequences. As researchers at Oxford’s Environmental Change Institute have emphasized, natural non-forest ecosystems are under major threat from agriculture yet remain sidelined in global frameworks designed around forest protection. Regulations aimed at curbing deforestation often define risk in terms of tree cover, which means that commodities grown on recently converted savannas, steppes, or peatlands can still enter “deforestation-free” markets. The European Union’s deforestation rule, for example, focuses on forest clearing linked to specific commodities but does not extend equivalent safeguards to grassland conversion.
The result is a kind of displacement. When forest protections tighten or public scrutiny intensifies, agricultural expansion can simply shift sideways into neighboring non-forest habitats. From a climate and biodiversity perspective, that is a shell game rather than a solution, because many grassland and wetland systems store large amounts of belowground carbon and support specialized species that cannot relocate to cropland or forest.
The Western Corn Belt as a Case Study
The pattern is not confined to the tropics or to low-income countries. In the United States, the Western Corn Belt has experienced its own version of quiet conversion. A peer-reviewed analysis in the Proceedings of the National Academy of Sciences documented extensive grassland loss to corn and soy across the Dakotas, Nebraska, Minnesota, and Iowa, with associated impacts on prairie pothole wetlands that store carbon and filter water. That study, which can be accessed through open-source archives, showed that much of the new cropland replaced intact grassland rather than previously farmed or degraded fields.
The Western Corn Belt example illustrates a broader dynamic. When commodity prices rise or biofuel mandates expand, marginal lands that were previously uneconomical to farm suddenly become attractive. Grasslands and wetlands, which often sit on fertile but unplowed soil, are the first to go. The conversion is incremental, field by field, rather than occurring as dramatic clear-cuts, and it rarely triggers the kind of satellite-imagery headlines that Amazonian deforestation generates. Yet the cumulative ecological damage can rival or exceed the better-publicized loss of tree cover, especially when drainage of small wetlands is factored in.
Similar processes are underway in parts of South America, Central Asia, and sub-Saharan Africa, where rangelands and savannas are being converted to row crops and intensive pasture. In many of these regions, land-tenure systems and weak enforcement make it easier to plow native grasslands than to clear recognized forest reserves, further skewing expansion toward non-forest ecosystems.
What Is Driving the Conversion
The commodities behind this shift are familiar. Meat production, cereal grains, nuts, and oilseeds are the primary drivers identified in the new global analysis, all of them deeply embedded in internationally networked supply chains. Rising incomes and urbanization have increased demand for animal protein and processed foods, which in turn boosts demand for feed crops like soy and maize and for vegetable oils used in everything from cooking to cosmetics and biofuels.
This supply-chain connection creates a feedback loop that most trade policies still ignore. International agreements on deforestation-free sourcing have gained traction over the past decade, but there is no equivalent framework for grassland-free or wetland-free supply chains. A soybean grown on a recently plowed South American grassland faces no additional trade barrier compared with one grown on land that has been farmed for generations. For producers operating on thin margins, the economic signal is straightforward: convert the cheapest available land, which is often land that is not officially forest.
Domestic policies can amplify these pressures. Subsidies for biofuel feedstocks, tax incentives for agricultural expansion, and infrastructure projects that open previously remote regions all tilt the playing field toward conversion. Without explicit safeguards for non-forest ecosystems, those policies can undermine conservation goals even when they are framed as climate-friendly or pro-rural-development measures.
Mapping the Loss With Machine Learning
The latest global findings were made possible by a new generation of satellite-derived mapping tools that combine high spatial resolution with advanced classification algorithms. Projects such as Global Pasture Watch have produced annual 30-meter maps of grassland extent, allowing scientists to track subtle changes in grazing lands and natural prairies that would have been invisible in coarser datasets. Machine learning models trained on field data and expert-labeled imagery can now distinguish natural grasslands from croplands, plantations, and urban areas with increasing accuracy.
These tools build on decades of investment in open scientific infrastructure. Much of the underlying remote-sensing and ecological literature is indexed through platforms like the National Center for Biotechnology Information, which, although best known for biomedical research, also hosts interdisciplinary work on land-use change, ecosystem health, and climate impacts. Researchers can create personalized dashboards via MyNCBI accounts, enabling them to track new publications on topics such as grassland conversion and to curate relevant citations.
Those curated collections, managed through specialized bibliography tools, help synthesize findings from regional case studies, global modeling efforts, and policy analyses into coherent narratives for decision-makers. At the same time, evolving account settings and data-sharing policies are making it easier for researchers to link land-cover datasets with ecological and socio-economic information, deepening understanding of how agricultural expansion affects both people and nature.
Looking ahead, the combination of high-resolution mapping, open data, and targeted policy reform could begin to close the protection gap for non-forest ecosystems. Incorporating grasslands and wetlands into zero-conversion commitments, expanding conservation finance beyond forests, and recognizing the cultural and economic value of pastoral landscapes are all steps that flow logically from the new evidence. The data are clear: if the world continues to treat forests as the only front line in the fight against habitat loss, it will lose some of its most productive and irreplaceable landscapes by stealth, one plowed field at a time.
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*This article was researched with the help of AI, with human editors creating the final content.
