1.3.3 Final remarks

In this chapter we have assessed evidence for tipping dynamics across the biosphere, finding that many ecosystem tipping points are possible. Compared to tipping points in the cryosphere (Chapter 1.2) and ocean/atmosphere circulations (Chapter 1.4), biosphere tipping points tend to feature more co-drivers, including habitat degradation and loss, direct exploitation and nutrient pollution with often complex interactions (IPBES, 2019). Along with strong spatial variability, this often makes ecosystem tipping thresholds and risks more difficult to assess. However, these complexities also provide opportunities for action to avert tipping. 

While climate change is a common leading driver, requiring urgent global emissions phaseout, compared to the cryosphere or ocean circulation it is more possible to directly increase the resilience of some at-risk systems. Actions such as ecological restoration and inclusive conservation, adaptive management and improved governance can help protect biodiversity and bio-abundance and so help to maintain key stabilising feedbacks that can help counter tipping (see Chapter 3.2). Such restoration and regenerative land use practices would also help to draw down some carbon from the atmosphere, helping to slow climate change (Girardin et al., 2021; Rockström et al., 2021). Such ‘nature-based solutions’ would not be enough to stop climate change though, which can only be achieved with a rapid cessation of greenhouse gas emissions.

Most ecosystems considered in this chapter can also be considered social-ecological systems, with people living within, and being integral to, the dynamics of these systems (Folke et al., 2016, 2021). While in some heavily degraded ecosystems restoration might entail minimising human impacts, in most places actions like supporting sustainable livelihoods for local communities can better help promote both ecological restoration and support human wellbeing in a way that makes both more sustainable in the long term (IPBES, 2019). The rights of Indigenous peoples – whose territories cover more biodiverse area globally than officially protected areas (ICCA Consortium, 2021) – must be respected, and their knowledge recognised as critical. Many other societal shifts are also necessary to underpin ecological restoration, including transformative changes to the global food system and commodity consumption (which together are key drivers behind much habitat loss and pollution – IPBES, 2019).

From a research perspective, we have identified several critical areas where improved knowledge could help us better understand biosphere tipping dynamics. In particular, deep uncertainties exist around the relative strength of feedbacks controlling ecosystem tipping dynamics, such as the complex interactions between ecohydrological and fire feedbacks in forest, savanna and dryland biomes. The role of increasing extreme event frequency and intensity in reducing and overcoming ecological resilience is also critical for ecosystems such as coral reefs, mangroves and forests, but it is not well resolved in models. Plant adaptability and spatial variability are also not well represented in models, despite being key factors adding complexity to ecosystem tipping dynamics. More observations, experiments and improved models, and integrations across these, are all required to address these issues. 

Observations from field and remote sensing can also help monitor and detect declining ecosystem resilience, as well as potential early warning signals (see Chapter 1.6). Greater data sharing and international collaboration would improve both monitoring and understanding. Lastly, co-designing research with researchers from across the natural and social sciences, Global South and North, and from multiple knowledge systems including Indigenous and traditional ecological knowledge is critical for fully understanding ecological dynamics and the potential for tipping.