Little Scope for Large-Scale Climate Plantations Without Breaching Planetary Boundaries

Little Scope for Large-Scale Climate Plantations Without Breaching Planetary Boundaries
by Robert Schreiber
Berlin, Germany (SPX) Feb 18, 2025

A new study by researchers at the Potsdam Institute for Climate Impact Research (PIK) reveals that the potential for carbon removal through climate plantations is significantly lower than previously assumed when planetary boundaries are taken into account. Without encroaching on existing agricultural land, the study estimates that biomass-based carbon capture and storage (BECCS) could remove less than 200 million tonnes of CO2 in 2050-far below the billions of tonnes expected in many climate models.

The research is based on the planetary boundaries framework, a concept introduced in 2009 under the leadership of PIK Director Johan Rockstrom. This framework identifies nine critical environmental limits, including climate stability, forest and ocean health, and biodiversity. A recent planetary health check by PIK found that six of these boundaries have already been breached, four of which are directly relevant to land use for climate plantations: nitrogen input from fertilization, freshwater use, deforestation, and biodiversity loss. The new study is the first to systematically model how BECCS potential is constrained if these thresholds are respected.

"Our computer simulation is one of the most sophisticated applications of the PIK-developed biosphere model to date," said Wolfgang Lucht, head of the Earth System Analysis research department and co-author of the study. "It provides a crucial perspective on the climate debate, particularly as global temperatures exceed the 1.5-degree limit. Addressing climate change requires more than just reducing CO2 emissions; we must also consider other planetary boundaries to maintain Earth's system resilience."

The study was conducted as part of the four-year EU-funded NEGEM project on responsible negative emissions. It employed the LPJmL global biosphere model, which simulates water, carbon, and nitrogen cycles daily at a resolution of half a degree latitude and longitude. Findings indicate that several planetary constraints severely limit the potential for large-scale BECCS:

- Restricting nitrogen input from fertilizers lowers carbon removal potential by 21%.

- Protecting freshwater systems leads to a 59% reduction.

- Avoiding further deforestation reduces the potential by 61%.

- Preventing biodiversity loss diminishes it by as much as 93%.

With all four planetary limits in place and explicit protections for existing forests, the study estimates that only a fraction of the projected BECCS carbon removal-less than 200 million tonnes of CO2-can be achieved in 2050.

"The most effective climate strategy remains the rapid reduction of emissions to near zero," said Johanna Braun, PIK researcher and lead author of the study. "To expand the scope for climate plantations, we would need to allocate less land for agriculture. This could be facilitated by shifting toward a more plant-based global diet, which could free up significant pastureland for alternative uses."

Braun emphasized the broader implications of the findings: "Reducing animal product consumption not only cuts agricultural emissions but also alleviates pressure on scarce resources, ultimately supporting the health of the entire Earth system."

Research Report:Multiple planetary boundaries preclude biomass crops for carbon capture and storage outside of agricultural areas