The most effective ways to protect, preserve, and rebuild ecosystems

Below are the key takeaways and introduction to our research into preserving ecosystems. Read the full report.

Our key takeaways

• Ecosystem health provides a holistic view of ecosystems, taking into account their biodiversity, functioning, and resilience. As such, we recommend focusing on ecosystem health as a measure of ecosystem integrity and collapse risk. The ecosystem health approach also incorporates intuitive notions of preserving vibrant ecosystems. Biodiversity, on the other hand, is unlikely to be a useful metric for prioritization as it can conflict with other aspects of ecosystem integrity.
• The International Union for the Conservation of Nature (IUCN) has begun a process to assess the collapse risk of all ecosystems on earth based on an ecosystem health approach. There is not enough data yet to attempt a global prioritization based on ecosystem vulnerability. However, we recommend that philanthropists use the IUCN risk data to compare candidate interventions that have been selected along other metrics such as human welfare or climate impacts.
• We find that concentrating on wetlands, coastal systems and coral reefs as well as a geographical focus on Central Africa, Southeast Asia, and the Amazon Rainforest likely maximize the marginal impact of ecosystem protection. This analysis of marginal impacts—ecosystem services—aims to capture all impacts of an ecosystem on human welfare. Examples include water purification and flood protection. Because ecosystem services are not traded on markets, there is large uncertainty in any individual estimates of ecosystem service values. However, combining multiple studies leads us to conclude that the above focus areas are most impactful.
• An additional prioritization analysis based on climate impacts finds that carbon storage is largest for peatlands and seagrass beds, suggesting that protecting those ecosystem subtypes is particularly important. In general, climate benefits are to a large degree included in ecosystem services. However, climate tipping points include the Amazon rainforest, which underscores its potential as a high-benefit ecosystem. Lastly, we do not have enough certainty to recommend a particular prioritization based on animal welfare considerations or risks of civilizational collapse.
• Principles of cost-effective conservation interventions are a focus on low-cost and low-yield countries and areas with a high chance of counterfactual development. Philanthropists should pay particular attention to potential displacement effects. Displacement occurs when conservation of a particular area merely shifts developers to expand on a different but equally societally valuable piece of land. If displacement is likely, conservation impact is low. To prevent displacement, we recommend funding large-scale projects that protect all or most of a specific ecosystem type within an area. However, these projects could negatively impact farmers as their most profitable land is no longer available. On a case-by-case basis, ecosystem benefits need to be weighed up against potentially lower farmer incomes.
• Water quality protection programs should focus on areas with high eutrophication¹ potential in low-cost regions (e.g., West and East Africa, and Southeast Asia). Lake Victoria, in particular, stands out as a potential focus area due to its high degradation risk and low intervention cost status. Additionally, we suggest philanthropists identify large organizations focusing on nutrient pollution of waterways and evaluate their cost-effectiveness based on whether their target areas are at risk of eutrophication, use proven nutrient pollution reduction interventions, and have low project costs.

An introduction

Ecosystems are ecological collectives defined by four elements (Keith et al. 2013):

1. A biotic component, such as the flora and fauna of an area
2. An abiotic complex, such as specific water resources
3. The interactions between and within the biotic and abiotic spheres
4. A physical space

As such, ecosystems are different from mere geographical landscapes or collections of animals or species. They describe environmental systems made up of different living and nonliving components and interactions between them. As a system, they can provide environmentally and socially important services such as water filtration or pollination. Adopting ecosystems as the unit of analysis therefore shifts the focus from conservation of certain areas or species to ecological collectives with various functions.

There is a wide variety of ecosystems on earth, from deep sea floors to savannas and caves. The International Union for the Conservation of Nature (IUCN) has developed a global typology of the various ecosystems. Starting from 4 global realms (terrestrial, subterranean, freshwater, and marine), the typology further segments ecosystems into 25 biomes within these realms. These biomes are at the level of generality of savannas, lakes, shoreline systems etc.²

Overall, ecosystems are threatened on a large scale today. While global numbers are hard to come by, select statistics indicate the degree of vulnerability. In North America, 33% of terrestrial ecosystems are threatened (Comer, Hak, and Seddon 2022). In Ecuador, 22% of forest ecosystems are threatened (Noh et al. 2020), and in China, 40% of wetlands are at risk (Convention on Biological Diversity).

This report provides a guide for philanthropists interested in protecting these threatened ecosystems. Section 1, Measuring Ecosystems, explores how the health and vulnerability of ecosystems can be quantified, investigating the concepts of ecosystem health, “preserving vibrant ecosystems”, biodiversity, and measures of collapse risk. Section 2, Impacts of ecosystem decline, analyses the benefits of ecosystem protection along the dimensions of human welfare, climate, civilization progress, and animal welfare. It concludes with a list of heuristics based on which philanthropists can find ecosystems that are most beneficial for society. Section 3, Conservation Philanthropy, evaluates the expected cost-effectiveness of various philanthropic approaches, including traditional conservation projects, and finally provides recommendations for the most cost-effective interventions to protect ecosystems.

Read the full report.

Notes

1. Eutrophication describes the process whereby an increase in nutrients in the water leads to excessive algae growth and a lack of oxygen to support other species. ↩

2. See Appendix Table 1 in Keith et al. 2020 for a full list and Global Ecosystem Typology for an interactive website to explore the typology. The section on Impacts of ecosystem decline uses this typology to prioritize across different interventions as the functions and thus the value that ecosystems provide vary across types. ↩