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 1 - 8 of 8
Gap Description Origin of source Source Resource Broad topic

Combination of NBS with grey infrastructure

 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-20-243-2021
  • Effectiveness of hybrid solutions

demonstrate the economic viability of NbS in comparison to other types of solutions on a timescale compatible with that of global change.

 Desk Study Academic literature

Cohen-Shacham, E., Andrade, A., Dalton, J., Dudley, N., Jones, M., Kumar, C., Maginnis, S., Maynard, S., Nelson, C.R., Renaud, F.G., Welling, R., Walters, G., 2019. Core principles for successfully implementing and upscaling Nature-based Solutions. Environmental Science & Policy 98, 20–29. https://doi.org/10.1016/j.envsci.2019.04.016
  • Effectiveness of hybrid solutions
  • Effectivennes at different time scales

Fourth, there is insufficient information for practical design and implementation of BGI. For example, scenarios combining BGI and grey infrastructure or different levels of implementation of BGI would help understand investments needs

 Desk Study Academic literature

Hamel, P., Tan, L., 2021. Blue–Green Infrastructure for Flood and Water Quality Management in Southeast Asia: Evidence and Knowledge Gaps. Environmental Management. https://doi.org/10.1007/s00267-021-01467-w
  • Effectiveness of hybrid solutions

Furthermore, the question concerning performance of “networks” (or “trains”) of interconnected small-scale NBS, as well as their hybrid combinations with large-scale NBS and grey infrastructure still remains unclear and should be addressed in the future work.

 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.
  • Effectiveness of hybrid solutions
  • NbS interaction at the landscape scale

In particular, input may be required from those with expertise in monetary valuation of NBS, to understand data on primarily the economic values- side, but also on the prices- side of NBS cost-benefit analyses, enabling more realistic comparisons with hard-engineered approaches especially at finer scales and in specific development contexts

 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.
  • Effectiveness of hybrid solutions

In view of the complementary costs and benefits of NbS versus engineered approaches to dealing with the risks posed by climate change, there is growing consensus among ecologists, engineers and managers that a combination of green and grey may be the best solution in many contexts

 Desk Study Academic literature

Seddon, N., Chausson, A., Berry, P., Girardin, C.A.J., Smith, A., Turner, B., 2020. Understanding the value and limits of nature-based solutions to climate change and other global challenges. Phil. Trans. R. Soc. B 375, 20190120. https://doi.org/10.1098/rstb.2019.0124
  • Effectiveness of hybrid solutions

More information is needed on the synergies and trade‑offs of combining NbS with grey infrastructure (i.e. hybrid measures).

 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.
  • Effectiveness of hybrid solutions

What are the costs and multiple benefits generated by different types and scales of NBS and hybrid solutions ?

 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.
  • Effectiveness of hybrid solutions