What is biodiversity enhancement?

Biodiversity enhancement refers to actions and strategies aimed at increasing the variety of life in all its forms, including species diversity, genetic variation, and ecosystem diversity.

Addressing biodiversity with NbS

Evaluating biodiversity net-gain when implementing a NbS requires a thorough understanding of the characteristics of the ecosystem in question before biodiversity targets can be set. A so-called baseline assessment must include information about the ecological state, the main drivers for biodiversity loss, and potential for improvement. This information should have a scientific basis while also making use of local knowledge, where possible.  

 

What to think about...

The evaluation of biodiversity enhancement is not always as straightforward as it sounds, and the following factors should always be considered when evaluating biodiversity enhancement in NbS: 

  • Scale: NbS implementation may cause a species increase locally, but without considering this increase in a wider regional or even global context, it is difficult to evaluate the biodiversity benefit. For example, if the NbS favors common species at the expense of uncommon, or endemic species, an increase in species richness cannot be considered a benefit for biodiversity as a whole. The implementation of NbS should therefore consider potential conflicts associated with the protection of species or habitats of special interest (e.g., species listed in the annexes to the Habitats Directive; IUCN red listed species). 

  • Target species: It is important to consider which species are and are not desired as an outcome of an implemented NbS. A lower number of desired target species (e.g. species being typical for the ecosystem, red-listed species, or keystone species) may often be a more desirable outcome than a large number of undesirable species. A large number of species that are common everywhere, or even worse, invasive to the region, are not generally a desirable outcome for biodiversity.  

  • Context dependency (ecosystem type/ local legislation): The evaluation of biodiversity enhancement for the same NbS may differ depending on the region. For example, rewetting of former wetlands can mediate both an increase and a decrease in species richness, depending on the characteristics of the area and the rewetting approach. If an area has potential to regain characteristics of a poor fen (low productivity), an increase in species richness may not be considered a biodiversity enhancement if this is a result of a high amount of nutrients in the water used for rewetting. Local legislation may help set goals for the desired biodiversity outcomes, for example if there are existing management plans for specific species or nature types. 

  • Connectivity: To ensure the long-term persistence of the target species of an NbS, it is important to consider landscape connectivity. If a population of species is isolated and unable to move to other areas to feed or reproduce, it is less likely to be able to survive over time. It is therefore always better to have the whole landscape in mind – e.g. are there other areas near the area of interest that can be used as corridors for movement or as foraging areas? Are there barriers around the area of interest that stop the species from being able to move, feed and reproduce? Ideally, NbS should improve biodiversity over the long term and across a large area by linking conservation efforts with more specific NbS measures within the region.  

To ensure that the NbS is meeting its goals for biodiversity enhancement, it is also essential to have monitoring in place to follow up on these goals. Better monitoring will help us to learn more about the efficacy of different NbS in the Nordic region and inform management to halt biodiversity declines.   

NbS with a focus on biodiversity enhancement

To ensure that every NbS has biodiversity benefits, it is essential to consider the context-specific potential that is determined by ecosystem characteristics. We encourage users of this handbook to fully realize the biodiversity potential within the specific context of the ecosystem and to set clear biodiversity targets that can be followed over time. 

Are you unsure how to choose an NbS that addresses biodiversity enhancement? See our general guidance on Nature-based solutions!