Study finds land availability limited to achieve biodiversity targets and apply climate mitigation strategy

Limitations in land availability could pose challenges in implementing biodiversity targets and a specific climate mitigation strategy, according to a new study published in journal Frontiers in Climate.

Countries have pledged 120 million square kilometres for land-based carbon dioxide removal (CDR) to achieve Net Zero goals. CDR involves activities removing carbon dioxide (CO2) from the atmosphere and durably storing it in geological, terrestrial or ocean reservoirs or products.

Countries have already committed in their nationally determined contributions (NDCs) to deploy additional CDR activities in the range of 100–650 metric tonnes of carbon dioxide equivalent (MtCO2) annually by 2030. Land-based CDRs include afforestation or reforestation, peatland management, and soil carbon sequestration, among others.

Read more: COP15 Montreal: Asia must speed up its protected area coverage 6 times to meet 30X30 goal

In 2022, nations agreed on a biodiversity “30×30” target, which aims to safeguard 30 per cent of the world’s terrestrial and marine areas by 2030. As of 2023, protected areas cover roughly 16 per cent of the world’s terrestrial area and 8 per cent of the world’s marine area.

“Climate change commitments and biodiversity conservation policies depend on land use. While some climate change mitigation strategies are also beneficial for biodiversity conservation, other land-based mitigation strategies are likely to conflict with the need to establish more protected areas due to the limited amount of land available,” the researchers wrote in their paper.

Of the available ice-free land of 130 million square kilometres (Mkm2), roughly 50 Mkm2 is used for agriculture and 30 Mkm2 for agroforestry.

As of 2023, roughly 12.3 Mkm2 of land is under protected areas. Per the 30×20 framework target, this figure has to be increased to 30 per cent, or 23 Mkm2, by 2030. 

Further, according to the paper, the international community has pledged to restore nearly 10 Mkm2 of degraded land, including around 20 per cent of existing cropland and 10 per cent of forest land.

Though the “30×30” target is ambitious, it may still not be enough to stop biodiversity loss as researchers estimate that a minimum of 44 per cent of global land (64 Mkm2) should come under protected areas to conserve biodiversity.

Read more: Faces of protection: 30×30 goal impossible without indigenous participation

Also, CDR activities alone cannot fulfill the Paris Agreement goal of limiting global warming to 1.5 or 2 degrees Celsius.

Further, the researchers raise doubts about the current commitments. For example, one question was how countries aim to allocate an additional 20.8 Mkm2 of land for establishing protected areas and restoring degraded land while also expanding food production and land-based CDR.

Large-scale deployment of CDR would require significant land-use changes, undermining the 30×30 goal. “This in turn would result in further biodiversity loss and could exacerbate competition for land used for food crops,” the paper reads.

When the two targets are compared, CDR policies are less important. Under the relevant treaty rules of international environmental law, emphasis is placed on emission reduction activities such as the rapid phasing-out of fossil fuels and minimising livestock farming, the researchers highlighted. In contrast, establishing protected areas is the primary measure for conserving biodiversity.

Read more: Protecting 30% of Earth’s surface for nature means thinking about connections near and far

However, the researchers argued that certain land-based CDR approaches, such as ecosystem restoration and the protection of existing sinks, could benefit biodiversity. There is no legal clause preventing the implementation of land-based CDR techniques and protected areas on the same parcels of land. 

The team recommended that governments focus on those CDR policies that effectively absorb greenhouse gases while also protecting biodiversity.

“The threat to biodiversity posed by climate change itself is far greater. If countries continue to emit greenhouse gases under a business-as-usual scenario, there would be severe consequences for all ecosystems and species,” the experts wrote.