Spatial configuration of patches with different ecological maturity: Implications for service supply at the landscape level

Abstract

Traditional agrarian landscapes have been managed over centuries to provide complementary ecosystem services (provision and regulation) in a sustainable manner. The spatial arrangement of patches in these landscapes seems to connect ecosystems of different maturity that complement each other functionally, through exchanges of matter and energy, optimizing provisioning services supply while minimizing management effort (e.g., water and fertilizers supply). In this study we explored the implications that the spatial pattern of patches with different degrees of maturity (grasslands, scrublands, and oak groves) may have on service provision within an agrarian multifunctional landscape. To assess the ecological maturity of the evaluated patches, we sampled biotic and abiotic variables related to compositional and structural complexity of the plant community, as well as soil characteristics. Our results show that less mature ecosystems (grasslands) adjacent to the most mature ones (oak groves) had a higher structural complexity of the plant community than those adjacent to ecosystems with intermediate maturity (scrublands), which could be associated to a higher resource flow from oak groves. Furthermore, the relative topographic position of oak groves and scrublands influenced the ecological maturity of grasslands. Grasslands topographically located below oak groves and scrublands had more herbaceous biomass and fertile soils than grasslands located above them, which suggests that resource flow is accelerated by gravitational forces. This indicates that grassland patches can have higher human exploitation rates when located below the more mature patches, which can increase agricultural provisioning services (e.g., biomass extraction). Overall, our findings suggest that agrarian provisioning services can be improved by spatially arranging the patches that provide such services (e.g., grasslands) in the landscape, as well as those patches responsible for ecosystem regulating services, such as water flow regulation and material accumulation (e.g., forests).

Keywords: Agrarian landscape; Ecological maturity; Ecosystem services; Patch boundary; Principal component analysis; Topographic position.