Nature-based solutions knowledge gaps

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

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

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.

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

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.

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)

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

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.

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.