1.This report seeks to understand the role that nature-based solutions can and should play in the UK’s path to net zero. Nature-based solutions are actions that involve working with nature to address the climate and biodiversity crises, as well as other societal challenges. They include actions that protect or restore natural ecosystems, or that manage working land sustainably. They can also help the UK and the world to achieve net zero emissions. The means by which they can mitigate climate change include by drawing down greenhouse gases from the atmosphere and by preventing further emissions from habitat degradation. But nature-based solutions are not a substitute for decarbonising all sectors of the economy, which remains the main task. Their potential contribution to a net zero world should not be overstated. However, compared to other means of drawing down greenhouse gases, they may have substantial co-benefits. These co-benefits include mitigating flood-risk and reducing other climate impacts, improving water and air quality, increasing biodiversity, and providing areas for human recreation.
2.Not every scheme that uses natural processes to sequester greenhouse gases is a nature-based solution. Establishing a single species (monoculture) tree plantation on formerly species rich grassland would sequester CO2, but it would provide fewer biodiversity benefits than the grassland it replaced, so it would not be an effective nature-based solution. Some practices may be nature-based solutions in one area, but not in another. Planting the right tree in the right place is certainly beneficial. But tree-planting on deep peat, as occurred in the UK in the 1970s, leads to net environmental harm. Careful, ecologically sensitive, location and future climate specific planning are essential to attaining the emissions reductions and the attendant co-benefits of nature-based solutions.
3.Schemes must be monitored to ensure that any carbon sequestered, and any other benefits, are permanent (at least on societally relevant timescales) and additional. Additional means that more CO2 is sequestered than there would have been in the absence of the interventions. In the absence of regulations to reduce emissions at source, schemes that treat nature-based solutions as a way of offsetting ongoing greenhouse gas emissions could allow polluters to continue polluting—acting as a sort of ‘get out of jail free card’. In the climate change context this is called “mitigation deterrence.”
4.In October 2021, we wrote to the President for COP26, Rt Hon Alok Sharma MP, calling for nature-based solutions to be included in the COP decision text. At COP26, the UK Presidency’s initial draft of the text included a reference to “nature-based solutions”. This was later changed to “protecting, conserving and restoring nature and ecosystems”, which echoes the International Union on the Conservation of Nature definition of nature-based solutions. In the letter, we outlined principles that should underpin the roll-out of nature-based solutions:
(a)Nature-based solutions are not a substitute for rapid decarbonisation of all sectors of the economy.
(b)Nature-based solutions should involve a wide range of ecosystems on land and in the sea, not just tree-planting.
(c)Nature-based solutions should be designed and implemented in partnership with local communities and stakeholders.
(d)Nature-based solutions should provide measurable benefits to biodiversity.
(e)Protection of existing ecosystems should be emphasised.
(f)Resilience must be a key factor in design and implementation.
(g)Any carbon benefits claimed must be rigorous in their accounting.
(h)Substantial financing and expertise should be provided by wealthy nations to poorer nations, subject to suitable regulations.
5.The Government has committed to domestic and international targets that will require nature-based solutions to be deployed at scale. To achieve the domestic net zero target by 2050, the Government’s indicative pathway is that net emissions from the agriculture, forestry and other land use sector must fall by between 70 and 80% by 2050. Internationally, the UK has committed to “reverse global biodiversity loss”, and to ensure that 30% of land and 30% of marine areas are “protected for nature” by 2030. Even with optimistic assumptions about productivity increases in agricultural land, meeting these targets will require widespread changes in land-use. Experience has shown how much easier it is for governments to announce targets than to meet them.
6.Environmental policy has been devolved to the nations of the UK, and the conclusions and recommendations in this report are aimed at the UK Government. But many of the issues identified and suggestions made apply equally to the devolved nations, which will all need ambitious policies to meet the challenge of climate change.
7.On 21 July 2021 we launched our inquiry into nature-based solutions for climate change. We heard oral evidence from multiple witnesses and we received over 40 written submissions. We invited experts to comment on our letter to the President of COP26. We are grateful to all who provided evidence and contributed to our seminar discussions. We thank our specialist advisor for this inquiry, Professor Pete Smith, Professor of Soils and Global Change, University of Aberdeen.
8.Chapter 2 of this report outlines the key habitats in the UK for nature-based solutions. It discusses the state of the UK’s natural environment and outlines the scientific uncertainties that remain for each habitat, as well as their potential contributions to achieving net zero emissions. Chapter 3 of the report discusses the Government’s policy. It outlines the targets that the Government has set and the mechanisms that it must put in place to support these, as well as the obstacles to deploying nature-based solutions.
1 Letter from the House of Lords Science and Technology Committee to the Rt Hon Alok Sharma MP, COP26 President, 15 October 2021:
2 Carbon Brief, ‘COP26: Key outcomes for food, forests, land use and nature in Glasgow’ (17 November 2021): ; and IUCN, ‘IUCN Global Standard for NbS’: [accessed 17 December 2021]
3 HM Government, Net Zero Strategy: Build Back Greener (October 2021) p 169: [accessed 17 December 2021]
4 HM Government, ‘Global Ocean Alliance: 30 by 30 Initiative’: [accessed 29 November 2021]
5 The Committee on Climate Change estimate that to meet net zero by 2050, a fifth of agricultural land will have to be converted to some form of carbon sequestration or practice that reduces emissions: The Committee on Climate Change, The Sixth Carbon Budget The UK’s path to Net Zero (December 2020) p 170: [accessed 17 December 2021]