Multifunctionality of an Urbanized Coastal Marine Ecosystem

Abstract

Coastal marine ecosystems provide numerous invaluable services and benefits to humankind. However, urbanization of coastal areas has homogenized and reduced the biodiversity of the surrounding marine environment and the sustainability of the multiple ecosystem services it provides. Studies have focused on single ecosystem functions despite human populations relying on several functions being delivered at once (known as multifunctionality). This study investigates five ecosystem functions (primary productivity, herbivory, predation, organic matter decomposition and carbon sequestration) and overall multifunctionality in four sites along a gradient of 16 environmental parameters. Ecosystem function varied significantly between sites that were farthest apart. In determining factors that drove ecosystem functioning, we found a positive relationship between coral cover and primary productivity but negative relationships between coral cover and levels of herbivory and predation intensity. Higher temperatures and greater concentrations of chlorophyll-a had a positive impact on predation and herbivory, respectively. Notably, we found a significant negative impact of total inorganic nitrogen and significant positive impact of total Kjeldahl nitrogen on carbon sequestration. Further, individual functions were compared with fish abundance (obtained from seawater eDNA), and benthic community composition (obtained from plate % coverage of autonomous reef monitoring structures). Increasing herbivorous fish abundance had a positive impact on Ulva mass loss. Overall, relative abundance of predatory, omnivorous and planktivorous fish exerted overriding influences on primary productivity and predation intensity, implying that fishing pressure and marine protected area status are important factors. Importantly, we found significant effects from environmental parameters indicating that reliably predicting the effects of future anthropogenic impacts will not be straightforward as multiple drivers are likely to have complex effects. Taken together, urbanized coastal ecosystems exhibit varying levels of multifunctionality depending on the extent of human impact, and the functional diversity of the benthic community present.

Inter-annual variability patterns of reef cryptobiota in the central Red Sea across a shelf gradient

“…Only a few studies focused on the largest fraction of the reef biodiversity (the cryptobenthos) 59 , 60 . While ARMS have previously been used to investigate differences in the cryptobiome across spatial gradients (e.g., 5 , 16 , 48 , 49 , 51 , 53 , 54 , 61 , 62 , to the authors knowledge this is the first time a temporal aspect has been incorporated into the analysis of cryptobenthic communities associated with ARMS and across a bleaching event.…”

Conservation in coastal soft‐sediment ecosystems: valuing places and recovery

“…The concept of multifunctionality acknowledges that ecological functions interact with and can be dependent on one another. There are numerous studies that explore methods for calculating multifunctionality, which involves measuring functions and assessing them together under a framework of multifunctionality (e.g., Alsterberg et al 2014; Dooley et al 2015; Archana & Baker 2020; Siwicka et al 2020; Siwicka et al 2021; Zhang et al 2021).…”