Forest soils in southwestern Germany absorbed about 3% more methane each year on average over up to 24 years of measurements, according to a study by the University of Göttingen and the Baden-Württemberg Forest Research Institute. Lead researcher Martin Maier said the team "observed a significant long-term increase in methane uptake," in a summary republished by ScienceDaily on Oct. 17.

The finding runs against earlier U.S. research showing forest soils taking up less methane over time. Together, the studies suggest this small natural climate sink behaves differently from place to place, which matters for how scientists estimate the world's methane budget.

It is modest good news, not a fix — methane is a potent greenhouse gas, and soil uptake removes only a small share of it. Nothing in this research offsets emissions from fossil fuels, agriculture, or landfills.

Microbes That Eat Methane

Methane traps far more heat than carbon dioxide over its first two decades in the atmosphere, which is why scientists track every source and sink closely. Most methane is removed by chemical reactions in the air. Soils are the only significant biological sink.

Healthy forest soils host bacteria that use methane as an energy source, consuming it from air that seeps into the ground. How much they remove depends on how easily gas can move through the soil.

The German team measured soil gas every two weeks at 13 forest sites through thin tubes buried in the ground, then confirmed uptake with airtight chambers on the surface. Uptake was highest when rainfall was lower, and temperatures were higher.

The researchers offer two explanations. Drier soil has more air-filled pores, letting methane reach deeper layers where microbes live. Warmer conditions can also speed up the microbes' activity, so they consume methane faster.

A Long Record From Southwest Germany

The study, published in Agricultural and Forest Meteorology in December 2025 and first publicized by the university in February, draws on a forest monitoring program that has run for more than two decades. Uptake varied widely among the 13 sites, but the overall upward trend held. The team's long record matters because methane uptake swings from season to season and year to year, so a trend of a few percent a year only becomes clear after many years of repeated measurements.

It is an observational, peer-reviewed field study limited to one region of Germany. It found an association between warmer, drier conditions and greater methane uptake. It did not prove that warming caused the increase at every site, and it does not mean climate change benefits forests overall. The release did not list funding sources.

Maier argued that long monitoring is essential to see real trends. He suggested that short studies, or analyses that pool very different forests, can hide gradual regional changes.

Northeastern U.S. Forests Tell a Different Story

The German result stands out because earlier American work pointed the other way. A 2018 study by Xiangyin Ni and Peter Groffman, summarized by the Cary Institute of Ecosystem Studies, found uptake fell 53% to 62% at forest sites in the Baltimore area over 18 years and 74% to 89% at New Hampshire's Hubbard Brook Experimental Forest over 14 years. The authors blamed wetter soils that block gas from reaching microbes.

Groffman drew a cautious lesson. "We can't rely on natural processes to solve our greenhouse gas problems," he said.

That explanation is itself now under debate — a paper published in July 2026 in Biogeosciences re-examined the same Baltimore and Hubbard Brook data and found rainfall and soil moisture explained less than 1% of the variation in methane flux. Its author, an independent researcher, proposed that the decline may instead reflect damage to methane-eating microbes, possibly from nitrogen pollution or invasive earthworms.

A Small Sink with Big Accounting Stakes

Upland forest soils remove roughly 22 to 38 million metric tons of methane a year, about 5% of the planet's total methane sink, according to the Biogeosciences paper. Small changes in that sink can shift global estimates, and climate models depend on getting it right.

The studies together suggest the answer depends on local rainfall, soil type, pollution, and land use. A forest in Germany may gain uptake while one near Baltimore loses it. That is a reason for more long-term monitoring stations, not for assuming forests will offset rising methane.

The disagreement also shows why U.S. ecological monitoring sites matter. Hubbard Brook and the Baltimore Ecosystem Study are long-running research forests whose records now underpin a global debate, and the German result depended on a state forest program that kept measuring for more than two decades. Gaps in such records make it harder to tell real trends from short-term noise.

The divide is not about whether methane harms the climate. It is about how a small natural process responds to changing weather, pollution, and soil life, and the answer appears to vary by region.

For readers, the practical lessons are indirect. Protecting healthy forest soils, limiting nitrogen pollution and supporting long-running ecological monitoring programs help preserve this natural sink. Cutting methane at its sources, from leaking gas infrastructure to landfills, remains the step that matters most.

The bottom line is that German forest soils are absorbing a bit more methane as conditions turn warmer and drier, while some U.S. forests are absorbing far less for reasons still in dispute. The sink is real but small, and it will not make up for human emissions.

What Readers Want to Know

What did the German study find?

Soils at 13 forest sites in southwestern Germany absorbed about 3% more methane each year on average over up to 24 years.

How do soils absorb methane?

Bacteria in the soil use methane as an energy source. Drier, airier soil lets more methane reach them.

Does this cancel out human methane emissions?

No. Forest soils remove only about 5% of the global methane sink, and the increase is small.

Why did U.S. studies find declines?

A 2018 study linked falling uptake at Baltimore-area and New Hampshire forests to wetter soils, though a 2026 reanalysis points to microbial damage instead.

Is this study new?

The paper was published in December 2025 and publicized in February 2026. It recirculated in October through ScienceDaily.

What can people do to protect this sink?

Supporting healthy forests, reducing nitrogen pollution, and cutting methane at its sources all help.