For decades, ecological researchers and practitioners have been examining, experimenting with, modelling, or managing bits of the natural environment. From this painstaking work, we know vastly more about ecosystem function and how biodiversity is maintained than we did fifty or sixty years ago. Sadly, this gain in knowledge is driven by the need to understand the complex ways human activities have impacted nature. We know a lot about the consequences of clearing forests, building cities, polluting rivers, overfishing, intensive farming, moving species around the globe, changing the climate, and the many other anthropogenic pressures which have contributed to the current state of nature, both in the UK and worldwide.
However, this knowledge is not just critical for understanding the crisis, it can also be repurposed. The more we understand how ecosystems work, the better we can identify the ways in which many environmental problems can be addressed by the enhancement, creation, management, and restoration of natural systems and the functions they perform. Some of these ideas are already very familiar. The notion that planting more trees can help capture and store carbon is well known from the media, practical conservation activities, government policy, and even commercial products (offsets anyone?). However, there are many other ways in which nature can be an important ally in addressing environmental problems – climate change in particular – and these are being increasingly bundled together under the term Nature-based Solutions (NbS). While such approaches draw on many different areas of ecological research, giving them a collective name hugely increases their public and policy visibility, and encourages a more holistic approach to their application.
A welcome guide to these ideas is a recently published report from the British Ecological Society (a CEE Bill supporter) titled Nature-based solutions for climate change in the UK. The report is the work of a large number of ecological scientists, drawn from across the BES membership, who have contributed their expertise to write, and independently review, eleven chapters summarising the options for Nature-based Solutions we could consider in the UK, their potential to address climate change issues, and the practical considerations associated with their implementation. The report primarily considers three roles for Nature-based Solutions: climate change mitigation, by reduction of emissions from ecosystems and increased sequestering of carbon; climate change adaptation, for example by flood reduction or cooling (and as pointed out by the recent Climate Change Committee report, a worryingly neglected issue); and benefits to biodiversity, by protecting or restoring habitats and making them more resilient. These are not the only benefits to be had from making use of what nature can do, but they reflect the particular expertise in the BES.
The UK is a mosaic of woodlands, heathlands, peatlands, grasslands, arable systems, freshwaters, coastal areas, and urban environments and, as the eight core chapters of the report explain, in all these restoration and enhancement of ecological processes could make significant contributions to climate change mitigation and adaptation. Whether it is rewetting degraded peat bogs, protecting and planting hedgerows, creating new salt marsh, encouraging the development of new woodlands, or enhancing urban green space, there are climate change benefits to be had everywhere. Moreover, the majority of these also have the potential to provide benefits for biodiversity and human well-being. So, if Nature-based Solutions “… have great potential to tackle the two defining crises of our age” (as reported by Seddon et al., 2020), then what’s stopping us?
As the report points out, NbS have to be implemented appropriately. Planting woodland – for which the current target is 30,000 ha per year by halfway through this decade – is good, but where? On productive agricultural land it may reduce food production and if the result is to increase food imports and consequently drive forest clearance in other countries then any benefits may be negated. Planting trees on peatlands compromises their carbon storage function, and planting on unproductive grasslands spares more productive land, but could destroy habitats important for biodiversity. There are many such trade-offs to be considered. The potential is there – in the case of woodland, development on low diversity, lower quality, grasslands, and other places such as steep slopes or peri-urban areas, could accommodate a doubling of tree cover – but will only be fully realised by doing it right. This example also makes clear that Nature-based Solutions are closely tied to the issue of agricultural and food system reform which, as the recent National Food Strategy Report highlights, sits at the critical intersection of health, climate, and biodiversity. The demands we place on the food system, such as levels of meat production, have significant implications for land availability for other purposes (such as woodland creation) and other impacts of agriculture, such as pesticide use, pollinator abundance, soil erosion, and water quality. By changing what we do with the land, and where we do it, we can have positive impacts on many of these issues.
And it is not just the ‘where?’ that matters, but also the ‘what?’ and the ‘how?’. In many cases, the delivery of effective mitigation or adaptation may require a combination of different Nature-based Solutions across a landscape. In the case of natural flood management, this could involve a coordinated programme of woodland planting, drainage blocking, wetland creation, stream side planting, floodplain restoration, and channel naturalisation across an entire catchment. Optimising the effectiveness of such suites of measures will need spatial planning: what goes where? It will also need governance, legislation, and incentives that create coherent action among multiple landowners and managers. How do we make it happen? As the report points out, these are challenges, but it also highlights the rapid development of new planning and assessment tools, and ideas about potential financial mechanisms to address many of these problems. None of the issues are insurmountable.
While it is clear that Nature-based Solutions alone are not sufficient to address the problem of climate change and must be coupled with curbs to demand and technical approaches, what is also clear is that right now we need all the tools in the toolbox. In particular, we should welcome tools that, like NbS, are available now, are cost-effective, can be implemented at large scales, and crucially, contribute to reducing the drivers and effects of climate change as well as benefiting biodiversity and people.
“Strategic and well-executed NbS will simultaneously provide significant additional public goods. This includes biodiversity benefits that could help drive the delivery of conservation targets and also benefit people’s health and wellbeing.” (Stafford et al., 2021)
All this echoes the central principle of the CEE Bill – that the twin problems of the climate and biodiversity crises should not be treated as separate, and that solutions to both must also consider fairness and equitability. The BES Report – although ecologically focused – also points out the potential importance of well-placed Nature-based Solutions for realising economic and social benefits, whether in the form of health and wellbeing or through the creation of green jobs. Comparatively low overhead and infrastructure requirements for many Nature-based Solutions may make for accessible and cost-effective employment.
The CEE Bill does not prescribe specific solutions (which are many and diverse) but defines the conditions to be met and principles to be followed. To complement this we need to assemble all the relevant ideas which can contribute to meeting those responsibilities and honestly assess their strengths and weaknesses. The BES report demonstrates that when it comes to Nature-based Solutions, we know a good deal about them and they have much to offer. Scientific challenges remain in the design of Nature-based Solutions, but novel approaches to governance and economic valuation are going to be critical to realising their potential.
It should perhaps come as no surprise that restoring and enhancing natural processes can help address many environmental problems. It is, after all, human alteration of ecosystems that lies at the root of so many of them. Ecological science is deeply engaged with the challenge of turning hard-won scientific understanding into these practical solutions but it is now critical to see that legislation drives their widespread application.
“Policy change will be necessary to overcome some of the challenges associated with NbS and to ensure that they fulfil their potential, yet the rewards are vital in meeting national climate change and biodiversity targets.” (Stafford et al., 2021)
1 – Stafford, R., Chamberlain, B., Clavey, L., Gillingham, P.K., McKain, S., Morecroft, M.D., Morrison-Bell, C. and Watts, O. (Eds.) (2021). Nature-based Solutions for Climate Change in the UK: A Report by the British Ecological Society. London, UK. www.britishecologicalsociety.org/nature-based-solutions
2 – Seddon, N., Chausson, A., Berry, P., Girardin, C.A.J., Smith, A., Turner, B., 2020. Understanding the value and limits of nature-based solutions to climate change and other global challenges. Philosophical Transactions of the Royal Society B: Biological Sciences 375, 20190120. https://doi.org/10.1098/rstb.2019.0120