Wildfires cause rapid changes to estuarine benthic habitat. (1st September 2022)

• Record Type: Journal Article
• Authors: Barros, Thayanne L.; Bracewell, Sally A.; Mayer-Pinto, Mariana; Dafforn, Katherine A.; Simpson, Stuart L.; Farrell, Mark; Johnston, Emma L.
• Is Part Of: Environmental pollution. Volume 308(2022)
• Publication Date: 2022-09-01
• Subjects: Bushfires -- Estuary -- Soft-sediment -- Coastal management -- Pyrogenic carbon -- Climate impacts; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2022.119571
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: Estuaries are one of the most valuable biomes on earth. Although humans are highly dependent on these ecosystems, anthropogenic activities have impacted estuaries worldwide, altering their ecological functions and ability to provide a variety of important ecosystem services. Many anthropogenic stressors combine to affect the soft sedimentary habitats that dominate estuarine ecosystems. Now, due to climate change, estuaries and other marine areas might be increasingly exposed to the emerging threat of megafires. Here, by sampling estuaries before and after a megafire, we describe impacts of wildfires on estuarine benthic habitats and justify why megafires are a new and concerning threat to coastal ecosystems. We (1) show that wildfires change the fundamental characteristics of estuarine benthic habitat, (2) identify the factors (burnt intensity and proximity to water's edge) that influence the consequences of fires on estuaries, and (3) identify relevant indicators of wildfire impact: metals, nutrients, and pyrogenic carbon. We then discuss how fires can impact estuaries globally, regardless of local variability and differences in catchment. In the first empirical assessment of the impact of wildfires on estuarine condition, our results highlight indicators that may assist waterway managers to empirically detect wildfire impacts in estuaries and identify catchment factors that should be included in fire risk assessments for estuaries. Overall, this study highlights the importance of considering fire threats in current and future estuarine and coastal management. Graphical abstract: Image 1 Highlights: ∙ Megafires represent an emerging threat to estuarine and coastal ecosystems ·The extent and proximity of wildfire influence the impact on estuaries ∙We identify relevant environmental indicators of wildfire in estuarine sediments ∙Concentration of nutrients, carbon, metals, and silt increased following wildfires ∙Changes to sediment condition are expected to cause ecological changes in estuaries