Nature-based solutions knowledge gaps

Explore the nature-based knowledge gap analysis below to help identify future avenues for research.

The knowledge gap database compiles an evidence base for nature-based solutions, to support defining research and innovation avenues, bolster policy and practitioners’ knowledge and knowledge-implementation. The database gathers 'gaps' collected through desk study and online consultations from August to October 2021 (see the NetworkNature report on practical, research and innovation needs for more information). 171 knowledge gaps were collected and categorized into 30 broad gap topics. This database will be updated during the course of the NetworkNature.


Displaying 121 - 140 of 169
Gap Description Origin of source Source Resource Broad topic

The effectiveness of small-scale NBs and large-scale NbS

Desk Study Academic literature

Ruangpan, L., Vojinovic, Z., Di Sabatino, S., Leo, L.S., Capobianco, V., Oen, A.M.P., McClain, M.E., Lopez-Gunn, E., 2020. Nature-based solutions for hydro-meteorological risk reduction: a state-of-the-art review of the research area. Natural Hazards and Earth System Sciences 20, 243–270. https://doi.org/10.5194/nhess-20-243-2020

  • Effectivennes at different geographical scales

The first group of knowledge gaps focuses on the effectiveness of NbS related to an incomplete evidence base concerning trade-offs and synergies between NbS for climate change mitigation/adaptation and biodiversity, human health, or social and economic aspects.

Desk Study Academic literature

Kabisch, N., Frantzeskaki, N., Pauleit, S., Naumann, S., Davis, M., Artmann, M., Haase, D., Knapp, S., Korn, H., Stadler, J., Zaunberger, K., Bonn, A., 2016. Nature-based solutions to climate change mitigation and adaptation in urban areas: perspectives on indicators, knowledge gaps, barriers, and opportunities for action. E&S 21, art39. https://doi.org/10.5751/ES-08373-210240

  • Synergies and trade-offs between goals

The following knowledge gaps are mainly related to research, planning and governance: insufficient knowledge of biodiversity (certain groups) and data on key ecosystem services in the area, but also the need for a common ground for prioritisation of biodiversity, ecosystem services and NbS at various administrative levels; and insufficient data on riparian forests and river pollutants

Desk Study Grey literature

De Vreese, R., 2021. Reviewing the knowledge on the importance of UF-NbS for resilient cities (D1.2).

  • Relationship between biodiversity, ecosystem functions and ecosystem services

The issue of monitoring the different scales of NbS impacts in both spatial and temporal dimensions, as well as the establishment of a common and holistic framework for the assessment of NbS impacts, are important directions for future research.

Desk Study Grey literature

Somarakis, G., Stagakis, S., Chrysoulakis, N., n.d. ThinkNature / Nature-Based Solutions Handbook. https://doi.org/10.26225/JERV-W203

  • Methodologies and tools for systematic evaluation
  • Monitoring tools

The links between air pollution mitigation and human health are not yet clear and conclusions tend to vary from study to study.

Desk Study Institutional publication

European Commission. Directorate General for Research and Innovation., 2020. Nature-based solutions: state of the art in EU funded projects. Publications Office, LU.

  • Impacts for health and well-being

The literature acknowledges the variation in size/type and scales of projects but there remains a lack of knowledge regarding the scale of activity necessary for social-environmental sustainability.

Desk Study Academic literature

Nelson, D.R., Bledsoe, B.P., Ferreira, S., Nibbelink, N.P., 2020. Challenges to realizing the potential of nature-based solutions. Current Opinion in Environmental Sustainability 45, 49–55. https://doi.org/10.1016/j.cosust.2020.09.002

  • Effectivennes at different geographical scales

The massive effort required for large-scale restoration of the planet's most degraded ecosystems requires robust scientific expertise on plant taxonomy. Field research on real forests cannot be replaced by satellite imagery, inventories and modelling alone. There is a need to closely investigate the habitats and plant lifestyle in original habitats, under the lens of simulating these environments in nature-based systems. Related to this, is the generation of adequate genetic material in every country, that is based on local plant species and varieties - eg. no imported plants for nature-based solutions to avoid species invasions.

Online public consulation University / Higher Education / Public research institute sector

BGCI (2021). State of the World’s Trees. BGCI, Richmond, UK.

  • Performance and characteristics of plants

The monetary profit generated by UF-NbS measures in the long term or the benefits from ecosystem services (society, health, environment, economy) are not sufficiently qualified and quantified.

Desk Study Grey literature

De Vreese, R., 2021. Reviewing the knowledge on the importance of UF-NbS for resilient cities (D1.2).

  • Effectivennes at different time scales
  • Cost/benefit evaluations

The new projects are developed just for a big cities however small countryside areas and towns have the problems of project staff, funding and at least Triple helix eco-system

Online public consulation Policy maker, advisor and public authority (national or local) sector
  • Effectiveness across socio-ecological contexts
  • Awareness and capacity building

The performance and characteristics of plants and soils for pollution control and water storage in different contexts under different maintenance regimes. More research is needed to estimate the particle-forming potential (plants emit species-specific volatile compounds that act as aerosol precursors), ozone forming potential (the same volatiles stimulate O3 formation and emission factors are missing for a huge number of species) and capacity of pollution uptake (data and models) for different plant species and plant-assembled NbS.

Desk Study Institutional publication

European Commission. Directorate General for Research and Innovation., 2020. Nature-based solutions: state of the art in EU funded projects. Publications Office, LU.

  • Performance and characteristics of plants

The second knowledge gap concerns the relationship between NbS and society and, more specifically, the stakeholder involvement and impact of human-nature interactions in forming or altering lifestyles, beliefs, and preferences while also considering place-impacts such as displacement and gentrification.

Desk Study Academic literature

Kabisch, N., Frantzeskaki, N., Pauleit, S., Naumann, S., Davis, M., Artmann, M., Haase, D., Knapp, S., Korn, H., Stadler, J., Zaunberger, K., Bonn, A., 2016. Nature-based solutions to climate change mitigation and adaptation in urban areas: perspectives on indicators, knowledge gaps, barriers, and opportunities for action. E&S 21, art39. https://doi.org/10.5751/ES-08373-210239

  • Social cohesion and environmental justice
  • Stakeholder engagement

The vague or very broad definition of the NbS that could lead to the possible confusion with other green “concepts” especially with green infrastructure on local scale. Moreover, on the national level, there is any mention of the NbS in legislative framework, e.g. Building Code, Act on nature and landscape protection, etc.

Online public consulation Policy maker, advisor and public authority (national or local) sector
  • Awareness and capacity building
  • Planning and policy frameworks

There is a general understanding about the possible impacts (benefits and co-benefits) of NbS solutions but, there is a lack of knowledge about how to design these NbS to maximize the benefits considering all the possible effects (positive impacts and trade-offs) to select the betterNbS per intervention (adapted to its local context)

Online public consulation Private Research Institute sector
  • Synergies and trade-offs between goals
  • Cost/benefit evaluations

There is a need for more standardised indicators to enhance cross-site comparisons of NbS

Desk Study Institutional publication

European Environment Agency., 2021. Nature-based solutions in Europe policy, knowledge and practice for climate change adaptation and disaster risk reduction. Publications Office, LU.

  • Methodologies and tools for systematic evaluation

There is also the need to better understand the direct climate mitigation benefits of NbS in terms of carbon sequestration and storage, but also indirect impacts such as the embedded carbon involved in the deployment of different types of solutions, and in a wider range of ecosystems beyond, e.g. forests

Desk Study Institutional publication

European Commission. Directorate General for Research and Innovation., 2020. Nature-based solutions: state of the art in EU funded projects. Publications Office, LU.

  • Relationship between biodiversity, ecosystem functions and ecosystem services

There is an urgent need to integrate NbS into policy goals related to health, economic development, finance, energy and construction in order to realise the full potential of NbS from a societal and economic perspective.

Desk Study Grey literature

McQuaid, Siobhán, Rhodes, Mary-Lee, Andersson, Thomas, Croci, Edoardo, Feichtinger-Hofer, Marianne, Grosjean, Matthieu, Lueck, Alina, Kooijman, Esmee, Lucchitta, Benedetta, Rizzi, Daniela, Reil, Alice, Schante, Joanne, 2021. From Nature-based Solutions to the Nature-based Economy - Delivering the Green Deal for Europe. Draft White Paper for consultation. Nature-based Economy Working Group of EC Task Force III on Nature-based Solutions. https://doi.org/10.5281/ZENODO.5055612

  • Planning and policy frameworks

There is limited understanding of the trade-offs involved in developing NbS for climate mitigation, both in relation to other environmental objectives (e.g. for biodiversity goals) and also in relation to other social and economic priorities. Further research on how NbS can be designed to contribute to the SDGs and the ways in which ‘just transitions’ can be enabled is needed.

Desk Study Institutional publication

European Commission. Directorate General for Research and Innovation., 2020. Nature-based solutions: state of the art in EU funded projects. Publications Office, LU.

  • Synergies and trade-offs between goals

There is not considerable knowledge regarding designing, implementing, and maintaining NbS or quantifying (including economic valuation) the benefits and co-benefits of their ecosystem services. There is also a lack of evidence of NbS effectiveness and the quantification of their environmental, economic, and social benefits.

Desk Study Grey literature

Somarakis, G., Stagakis, S., Chrysoulakis, N., n.d. ThinkNature / Nature-Based Solutions Handbook. https://doi.org/10.26225/JERV-W202

  • Cost/benefit evaluations
  • Synergies and trade-offs between goals

There is still limited understanding of the importance of biodiversity for ecosystem functioning and therefore services. A key example is soil. The contribution of broad groups of organisms to soil function is understood, but the contribution of the diversity of organisms within these broad groups is barely studied. This is also important in terms of resilience to environmental perturbations including climate change. In additional how management practices may alter soil biodiversity (e.g. grazing in grasslands) and therefore impact the resistance and resilience of soil processes to other perturbations.

Online public consulation University / Higher Education / Public research institute sector
  • Relationship between biodiversity, ecosystem functions and ecosystem services

Therefore, a more substantial knowledge and evidence base is needed in order to promote their wider acceptance and upscaling/uptake

Desk Study Institutional publication

European Commission. Directorate General for Research and Innovation., 2020. Nature-based solutions: state of the art in EU funded projects. Publications Office, LU.

  • Knowledge base