Nature-based Solutions (NbS) represent a modern framework that intentionally links the health of the natural world with the well-being of human societies. This approach moves past traditional conservation by explicitly recognizing that functioning ecosystems provide services that address complex challenges like climate change, water scarcity, and disaster risk. By protecting, restoring, and sustainably managing nature, these solutions leverage the inherent power of ecological processes to deliver tangible benefits to communities and economies. Investing in nature acts as infrastructure, offering a robust and often more cost-effective alternative to purely engineered interventions. This integrated perspective ensures that environmental actions simultaneously advance both ecological health and human development goals.
Defining Nature Solutions
Nature-based Solutions are formally defined by organizations like the International Union for Conservation of Nature (IUCN) as actions that protect, sustainably manage, and restore natural or modified ecosystems to address societal challenges effectively and adaptively. NbS projects must provide human well-being benefits, such as improved livelihoods or reduced risk, alongside gains for biodiversity. This dual outcome distinguishes NbS from simple conservation, which may focus solely on species protection.
The concept often overlaps with, but is broader than, “green infrastructure,” which is a subset of NbS that typically focuses on engineered systems using natural elements, such as green roofs or constructed wetlands in urban settings. In contrast, “gray infrastructure” refers to conventional, built-environment solutions like concrete seawalls, large dams, or pipes. NbS often proves to be more economically sound than its gray counterpart, providing a wider array of co-benefits and appreciating in value as natural systems mature.
Guiding Principles for Implementation
For a project to qualify as a true Nature-based Solution, its design and execution must adhere to a set of guiding principles, ensuring robust outcomes for both people and nature. A requirement is that the solution must support or enhance biodiversity, meaning projects cannot rely on non-native or single-species plantings. Biodiversity is the underpinning for ecosystem function, boosting the delivery of services like water purification or carbon storage.
Successful implementation also demands inclusive and participatory governance, requiring the full engagement and consent of Indigenous Peoples and local communities. Projects must respect local rights, champion local knowledge, and be explicitly designed to deliver a range of local benefits, including improved livelihoods or reduced vulnerability to climate impacts. Furthermore, Nature-based Solutions are not a substitute for the rapid phase-out of fossil fuels and must not delay urgent action to decarbonize global economies.
Application in Climate Adaptation and Mitigation
Nature-based Solutions play a substantial role in addressing the climate crisis through both mitigation and adaptation. For mitigation, healthy ecosystems function as significant carbon sinks, removing and storing carbon in biomass, soils, and sediments. Reforestation and the prevention of deforestation are powerful tools, as are the conservation and restoration of coastal wetlands and peatlands, which store carbon at a faster rate and for longer periods than many terrestrial forests.
NbS also strengthens human defenses against climate impacts. For climate adaptation, NbS provides natural buffers that increase community resilience against extreme weather events. Coastal areas benefit from the restoration of ecosystems such as mangroves and coral reefs, which act as natural breakwaters, dissipating wave energy and reducing storm surge height. In urban environments, the establishment of green infrastructure like parks, urban forests, and green corridors helps to combat the urban heat island effect by providing shade and cooling the air through evapotranspiration.
Enhancing Water Security and Biodiversity
Beyond climate action, Nature-based Solutions are highly effective in managing the hydrological cycle, directly contributing to water security and the preservation of biological diversity. Watershed protection programs restore upstream ecosystems such as forests and wetlands that naturally filter and regulate water flow. By maintaining these healthy source watersheds, cities can significantly reduce the sediment and nutrient loads entering their water supplies.
The restoration of natural floodplains and wetlands is another powerful NbS for water management, allowing these areas to absorb excess runoff during heavy rainfall events, thereby reducing flood risk for downstream communities. These ecosystems also facilitate the natural recharge of groundwater aquifers and can filter pollutants from agricultural runoff using vegetative buffers before the water enters rivers.
Measuring and Sustaining Project Impact
The long-term success of Nature-based Solutions depends heavily on rigorous monitoring, evaluation, and adaptive management. Quantifiable metrics are required across multiple dimensions, including social and economic indicators, not just simple ecological measures. Frameworks like the IUCN Global Standard for Nature-based Solutions provide criteria and indicators to guide the design and evaluation process, ensuring projects achieve their dual goals. Monitoring and evaluation track a project’s performance against a baseline and assess whether the solution is working as expected. To ensure the longevity of these interventions, long-term funding and robust governance structures are necessary to maintain restored ecosystems and ensure benefits continue to flow to communities.