Using multilayer socioecological networks to assess ecosystem service flow in a subsistence farming community in Papua New Guinea

Abstract Ecosystem services are rapidly degrading under anthropogenic pressure. Therefore, it is increasingly important to understand how ecosystem services flow, particularly at local scales, where people directly rely on nature for their livelihoods and well‐being. Many ecosystem services are underpinned by ecological (e.g. frugivory) and socioecological (e.g. cultivation) interactions, connected as multiple stages of ecosystem service flow. We use a multilayer network, constructed with local ecological knowledge, to assess how ecosystem services flow in a subsistence farming community in Papua New Guinea. Our results highlight the relative importance of plant species in directly providing different ecosystem services (e.g. food, medicine, etc.), as well as their role in structuring ecosystem service flow. Specifically, we found that firewood services may be more vulnerable to future environmental or social changes, with a single species, Pometia pinnata, disproportionately supporting over 30% of firewood services to the local community. Furthermore, we found that the value of plants to local farmers is linked to their role in maintaining connectivity of ecosystem service flow, with more important (i.e., less replaceable) plants for providing specific services also being more important for cohesive ecosystem service flows. The results of our study can be used to understand how disturbances could impact the provision of ecosystem services to local communities, as well as key species and actors that can influence the flow of ecosystem services under different conservation or agricultural practices. We also critically assess our framework, providing key lessons learned to improve accuracy for future applications. Read the free Plain Language Summary for this article on the Journal blog.