Nature as infrastructure - a hierarchy of impact, metrics and claims

Introduction

As we confront escalating climate challenges and biodiversity loss, there is a growing recognition that natural ecosystems should be valued as critical infrastructure.

Here we explore the concept of Nature as Infrastructure, proposing that investments at an ecosystem level are not only environmentally responsible but also economically sound. By treating nature as an asset that can yield measurable returns, we can channel investments into sustaining and improving ecosystem integrity, through high-level restoration and protection efforts, ensuring they remain durable, adaptable to perturbations like climate change, and capable of providing ecosystem services in perpetuity.

Through a structured consideration of a hierarchy of metrics, impacts and claims, this document provides a pathway for stakeholders, from corporations to governments, to make meaningful and verifiable contributions to ecosystem health, while positioning these efforts within a broader market for nature-based investments. By anchoring investments to the resilience of ecosystem infrastructure, we can create a sustainable legacy for future generations, with a clearer understanding of how to track and verify nature's valuable contributions to society.

Nature as infrastructure

In the context of nature investments and ecosystem restoration, viewing Nature as Infrastructure repositions natural ecosystems as critical assets with intrinsic value, similar to built infrastructure.

Just as a well-planned city relies on roads, bridges, and utilities to support the movement of people, goods, and services, an intact ecosystem infrastructure supports the movement and interactions of species, nutrients, and energy.

When the city’s infrastructure is carefully designed and maintained, it can handle increased demands, adapt to new challenges, and serve its residents effectively over time. However, neglected or poorly designed infrastructure results in breakdowns, inefficiencies, and costly repairs. Similarly, ecosystem infrastructure in good condition, such as connected habitats and balanced food webs, can withstand pressures like climate change, pollution, and habitat fragmentation.

However, unlike built systems, ecosystems in good condition are self-willed and self-maintaining, naturally fulfilling roles akin to city maintenance teams, and doing so with an effectiveness and efficiency that no engineered system can replicate. This ecosystem infrastructure provides essential ecosystem services—such as carbon sequestration, water purification, cultural services, soil fertility, and flood regulation—thereby delivering tangible returns to society and investors alike.

This perspective of nature as infrastructure emphasises that investments into nature should not just aim for isolated, fragmented gains (such as optimisation for carbon sequestration or mean species abundance), but should focus on the restoration and protection of the foundational structure, function, and composition of ecosystems. When intact and well-maintained, this infrastructure ensures the resilience and integrity of ecosystems, providing a myriad of ecosystem services, while avoiding the risks of narrow interventions and fragmented gains that could inadvertently undermine ecosystem functionality.

Investing in ecosystem infrastructure not only supports critical ecological functions but also offers significant cost advantages over traditional built infrastructure. For example, species reintroductions or the creation of wildlife corridors to facilitate recovery of trophic functions drives natural disturbance regimes, strengthens ecological balance and promotes genetic diversity, thereby reducing the need for continual intervention.

Similarly, restoring hydrological systems in degraded wetlands can naturally regulate water flow, reducing the need for costly artificial flood control measures; while enhancing vegetation diversity through native reforestation improves habitat complexity, resilience against invasive species, and carbon sequestration.

These interconnected restoration activities collectively reinforce the structure, function, and composition of ecosystems, providing both sustainable returns on investment and a cost-effective approach to landscape resilience and climate adaptability.

Hierarchy of impact and claims

The type and scale of investment in nature can vary, and this affects the type of claims that can be made in relation to the impact of those investments. Broadly the type of claim depends on whether you are targeting ecosystems, habitats or species (see Table 1). Specifically, higher-order restoration efforts aim at restoring ecosystems, whereas lower-order efforts focus on single species or specific habitats which have less of an impact on overall ecosystem function or integrity.

Whilst the initial investment for higher-order restoration may be higher, there are typically multiple ‘returns’, investments are more durable, and the ongoing operational or maintenance cost is lower.

In contrast, lower-order restoration often requires intensive management of species and habitats, focusing on parameters like rarity or cultural resonance, which can be high-cost but limited in fostering self-sustaining, dynamic ecosystems.

Higher-order restoration efforts are directed at restoring or maintaining the ecosystem infrastructure itself, ensuring the interconnectedness of natural processes across a landscape. These efforts are best measured using a jigsaw of interrelated metrics that capture structural, functional, and compositional aspects of ecosystem integrity.

Ideally, they should be relevant across different ecoregions to build a library of case studies, data feeds, and reference areas, ensuring claims in different jurisdictions are comparable in global nature markets.

However, taking a "shopping list" approach to nature metrics—where metrics are selected individually to suit preferences or project goals—risks neglecting the essential "nutrients" that underpin ecosystem function, much like choosing items from a shelf that may not fully align with health and well-being.

This fragmented approach can result in claims and units that lack fungibility, creating inconsistencies across projects and buyers.

To address this, a jigsaw of metrics should aim to capture indicators of structure, function, and composition, ensuring that key natural processes, such as species dispersal (Landscape Connectivity), food web complexity (Trophic Function), natural disturbance regimes (Vegetation Spatial Diversity), and niche utilisation (Bird Trait Diversity), are included. Claims made against these efforts can address ecosystem-wide impacts, focusing on improvements in ecosystem condition, integrity, and resilience. These are credible, high-level claims that reflect a meaningful return on investment into the ecosystem as an asset.

Lower- to middle-order efforts target specific species, populations or habitats that might be a focus of and relevant for local conservation efforts or that may be afforded priority or protected status, often improving isolated aspects of biodiversity without necessarily addressing long-term ecosystem-level resilience or integrity. These efforts are often evaluated using an unrelated basket of metrics, targeted metrics or multi-metric type approaches, which focus on measurable but isolated indicators, such as increases in specific species populations or habitat patches.

Integrity of claims

Claims associated with these lower-order efforts should be more limited in scope, focusing on specific biodiversity gains rather than systemic improvements. For instance, rather than claiming ecosystem-wide recovery, or gains in biodiversity, a lower-order project may claim that it has enhanced the population of a threatened species or improved the condition of a specific habitat.

Each level of claim should come with validation processes to ensure that claims made are credible. Higher-order claims about ecosystem integrity should involve extensive, longitudinal data collection and analysis, at the landscape scale, demonstrating that multiple ecological processes are being positively impacted. Users of such claims should be informed as to the validity of their claims, whether these relate to claims made by governments, corporate, or financial institutions. Such users should be guided in the use of this hierarchy and make claims in a way that avoids overstatement. For instance, only projects with measurable ecosystem-wide impacts should make ecosystem integrity claims, or claims about biodiversity gain, while projects focusing and reporting on individual species or habitats should make species and habitat-specific claims.

Ecosystem Services as Returns on Investment

By focusing at a higher-order ecosystem level, investors claim the delivery of ecosystem services benefits, as a return on their investments. Ecosystem services like carbon sequestration, water purification, and habitat for pollinators are inherently tied to the integrity and functionality of the ecosystem. Using this model, each landscape can be tailored to optimise associated ecosystem service benefits, resulting in a more resilient environment.

By investing in the restoration and preservation of ecosystem infrastructure, investments are effectively translated into sustainable ecosystem service provisioning assets that benefit both nature and people.

Metrics and indicators

When nature is treated as an asset, it is important to consider the types of metrics and indicators that can be used to evidence the recovery of the asset.

For example, both the Taskforce on Nature-related Financial Disclosures (TNFD) and the European Union Corporate Sustainability Reporting Directive (EU CSRD) encourage companies to focus on broader indicators of ecosystem health, such as ecosystem integrity, connectivity, and resilience to climate change, aligning with regulatory and financial disclosure requirements.

Similarly, the Science Based Targets for Nature (SBTN) emphasises setting science-based goals that promote ecosystem restoration and resilience, advocating for holistic approaches that move beyond single-species or habitat-specific metrics.

It is important to note that there are important natural processes and interactions happening between species and the habitats they reside in, with disruptions cascading through the ecosystem, undermining higher-order ecological functions and ultimately compromising ecosystem integrity and resilience. Recognising and preserving these interactions within a hierarchy of ecosystem metrics is essential and should not be overlooked.

An ecosystem condition index (created through a combination of interrelated ecological metrics) becomes a valuable tool for providing a quantifiable benchmark for assessing improvements in ecosystem integrity, making it possible to track the value of these assets over time. Projects can demonstrate the sustained provision of ecosystem services as an ongoing "yield" from well-maintained natural capital.

In brief

Nature as Infrastructure: By identifying ecosystems as critical infrastructure and valuable assets, nature investment schemes can prioritise the protection and restoration of ecosystem integrity, which is essential for long-term resilience and sustainable service provisioning as benefits for nature and society. These high-integrity, infrastructure-based projects can promise consistent and specific ecosystem service provisioning as a return on investment, making these higher-order, ecosystem-level investments more attractive and meaningful for investors.

Higher-Order Claims: Claims based on ecosystem integrity reflect systemic improvements and have validated claims against the ecosystem’s service provisioning. These claims should be supported by interrelated metrics that collectively measure ecosystem condition.

Lower-Order Claims: Lower-order claims are valid but limited in scope, typically associated with species and habitats, focusing on isolated gains without necessarily impacting overall ecosystem resilience.

By adopting this hierarchical approach to metrics, impacts and claims, nature markets can foster a more resilient, holistic, and impactful system of investment in nature, ensuring that each dollar invested contributes meaningfully to the long-term integrity of ecosystems and the services they provide.

Hierarchy of claims