Ecological processes that can be used for developing Nature-based solutions for biological invasions, aligned with the framework of Resist – Direct – Adapt. While processes aligned with resist and direct category can be used for developing solutions for controlling invasions, the processes aligned with adaptations can be used when invasions are beyond control and their negative impacts must be mitigated. The invasion magnitude, ecosystem novelty, human interventions and management cost incurred, in general, increase from dark green to light green.

By Ninad Avinash Mungi, Alejandro Ordonez Gloria, Rajat Rastogi, Jens-Christian Svenning.

Read the full paper here.

Invasive species, those species humans have introduced to ecosystems beyond the specie’s native range, are harming ecosystems and human well-being worldwide. A recent IPBES global assessment highlighted the urgency of controlling invasions globally. Traditional methods to manage invasive species often involve intensive, long-term interventions that can be costly with unintended negative effects on ecosystems and societies. For example, invasive species threaten around 66% natural forests and open ecosystems in India. Conventional methods like bulldozing invasive trees or chemical-control can harm native species and dependent people. In response, there is growing interest in Nature-based Solutions (NbS), which involves capitalizing on ecological processes to control invasions.

To ease the utilization of NbS for biological invasions for intended outcomes, we use an adaptive management typology ranging from resisting invasions, to directing a mixed-community of alien and native species, to accepting an invaded ecosystem. This framework offers flexible decisions by including severity of invasions, interactions with native species, degree of human interventions, and management goals. For example, in the Indian case:

  1. Resist: To control/resist herbaceous invasions, natural fire regime could be restored in fire-adapted savannas, whereas density and canopy of native trees could be conserved in wet forests, both known to reduce invasions effectively.
  2. Direct: The dominance of large-scale invasions could be reduced by introducing megaherbivores or biocontrol agents to guide the ecosystem towards a state with native species dominance, even if some invasive species remain.
  3. Adapt: When invasions are old-growth and extensive to reverse, strengthening human adaptations like utilizing invasive plant biomass for craft and furniture production may help mitigate the invasion-led loss of traditional ecosystem services, while also helping remove invasions.

NbS for biological invasions focuses on conserving/restoring ecological processes, serving co-benefits like enhanced biodiversity, improved ecosystem services, and contributing towards climate change mitigations. Such solutions can be more equitable by enabling adaptative choices of Indigenous Peoples and Local Communities and helping resolve ethical conflicts in removing invasive species. However promising, NbS are not a one-size-fits-all solution and require tailored scientific approaches. Nonetheless, they provide a way to manage biological invasions that is more aligned with ecological autonomy, aiming to reduce chronic human interventions.

A) Grassy ecosystems invaded by woody Lantana camara in Indian dry ecosystems. B) Uprooting Lantana camara by management team and local communities C) Recovery of native flora and megafauna that can potentially further resist dominance of invasions at the restored site D) utilization of Lantana camara plant parts for making baskets and other furniture by local communities. These efforts are seen as a combination of directing ecosystem towards biodiverse state while adapting to use invasive plant biomass for social and economic benefits (Photographs: A, B: Rajat Rastogi, C: Jayanta Bora, D: Kannan et al., 2014)