Effects of in situ experimental warming on metabolic expression in a soft sediment bivalve.

Ocean surface temperatures and the frequency and intensity of marine heatwaves are increasing worldwide. Understanding how marine organisms respond and adapt to heat pulses and the rapidly changing climate is crucial for predicting responses of valued species and ecosystems to global warming. Here, we carried out an in situ experiment to investigate sublethal responses to heat spikes of a functionally important intertidal bivalve, the venerid clam Austrovenus stutchburyi.

Seafloor sediment microtopography as a surrogate for biodiversity and ecosystem functioning.

Marine soft sediments play crucial roles in global biogeochemical cycles and biodiversity. Yet, with organisms often hidden in the sediment, they pose challenges for effective monitoring and management. This study introduces a novel approach utilizing sediment microtopography as a proxy for ecosystem functioning and biodiversity.

Integrating rapid habitat mapping with community metrics and functional traits to assess estuarine ecological conditions: A New Zealand case study.

Estuarine ecosystems are under pressure from anthropogenic stressors in many parts of the world. In a New Zealand estuary, we integrated rapid habitat mapping, univariate and multivariate benthic community metrics and functional traits-based metrics to provide a holistic assessment of its ecological condition. Our integrative approach identified 11 different habitat classes across the study estuary and revealed how univariate, multivariate, and functional traits-based metrics varied spatially.

Climatic, oceanic, freshwater, and local environmental drivers of New Zealand estuarine macroinvertebrates.

Understanding the responses of organisms to different environmental drivers is critical for improving ecosystem management and conservation. Estuarine ecosystems are under pressure from multiple anthropogenic stressors (e.g.

NZTD - The New Zealand Trait Database for shallow-water marine benthic invertebrates.

Macrobenthic traits, for example feeding mode, life history, morphology, are increasingly used for determining responses of macrobenthic fauna to environmental change and influences on ecosystem functioning. Yet, trait information is scarce or non-existent in several parts of the world, such as New Zealand. This deficit makes collecting trait data a difficult and time-consuming task, limiting its potential use in trait-based assessments.

Altered nitrogen transformation pathways and a legacy of sediment organic matter enrichment.

Estuaries are ecologically valuable ecosystems that process nutrients through complex biogeochemical processes. Here we identify drivers and inhibitors of nitrogen removal in unvegetated intertidal sandflats at six sites in Manukau Harbour (37° 2.00'S 174° 42.

Positive contribution of macrofaunal biodiversity to secondary production and seagrass carbon metabolism.

Coastal vegetated habitats such as seagrasses are known to play a critical role in carbon cycling and the potential to mitigate climate change, as blue carbon habitats have been repeatedly highlighted. However, little information is known about the role of associated macrofauna communities on the dynamics of critical processes of seagrass carbon metabolism (e.g.

Who is contributing where? Predicting ecosystem service multifunctionality for shellfish species through ecological principles.

A key challenge in environmental management is determining how to manage multiple ecosystem services (ES) simultaneously, to ensure efficient and sustainable use of the environment and its resources. In marine environments, the spatial assessment of ES is lagging as a result of data-scarcity and modelling complexity. Applying mechanistic models to link ecological processes with ecosystem functions and services to assess areas of high ES potential can bridge this gap and accommodate assessments of functional differences between service providers.

Sea Ice Dynamics Drive Benthic Microbial Communities in McMurdo Sound, Antarctica.

Climate change is driving dramatic variability in sea ice dynamics, a key driver in polar marine ecosystems. Projected changes in Antarctica suggest that regional warming will force dramatic shifts in sea ice thickness and persistence, altering sea ice-associated primary production and deposition to the seafloor. To improve our understanding of the impacts of sea ice change on benthic ecosystems, we directly compared the benthic microbial communities underlying first-year sea ice (FYI) and multi-year sea ice (MYI).

Informing the management of multiple stressors on estuarine ecosystems using an expert-based Bayesian Network model.

The approach of applying stressor load limits or thresholds to aid estuarine management is being explored in many global case studies. However, there is growing concern regarding the influence of multiple stressors and their cumulative effects on the functioning of estuarine ecosystems due to the considerable uncertainty around stressor interactions. Recognising that empirical data limitations hinder parameterisation of detailed models of estuarine ecosystem responses to multiple stressors (suspended sediment, sediment mud and metal content, and nitrogen inputs), an expert driven Bayesian network (BN) was developed and validated.

Climate cascades affect coastal Antarctic seafloor ecosystem functioning.

Polar seafloor ecosystems are changing rapidly and dramatically, challenging previously held paradigms of extreme dynamical stability. Warming-related declines in polar sea ice are expected to alter fluxes of phytoplankton and under-ice algae to the seafloor. Yet, how changes in food flux cascade through to seafloor communities and functions remains unclear.

Mapping the estuarine ecosystem service of pollutant removal using empirically validated boosted regression tree models.

Humans rely on the natural environment and benefit from the goods and services provided by natural ecosystems. Quantification and mapping of ecosystem services (ES) is required to better protect valued ES benefits under pressure from anthropogenic activities. The removal of excess nitrogen, a recognized catchment-derived pollutant, by biota in estuarine soft sediments is an important ES that potentially ameliorates the development of eutrophication symptoms.

Invasive ecosystem engineers threaten benthic nitrogen cycling by altering native infaunal and biofouling communities.

Predicting the effects of invasive ecosystem engineering species in new bioregions has proved elusive. In part this is because separating biological effects from purely physical mechanisms has been little studied and yet could help predict potentially damaging bioinvasions. Here we tested the effects of a large bio-engineering fanworm Sabella spallanzanii (Sabella) versus worm-like structures (mimics) on gas and nutrient fluxes in a marine soft bottom sediment.

Biodiversity breakpoints along stress gradients in estuaries and associated shifts in ecosystem interactions.

Denitrification in coastal sediments can provide resilience to eutrophication in estuarine ecosystems, but this key ecosystem function is impacted directly and indirectly by increasing stressors. The erosion and loading of fine sediments from land, resulting in sedimentation and elevated sediment muddiness, presents a significant threat to coastal ecosystems worldwide. Impacts on biodiversity with increasing sediment mud content are relatively well understood, but corresponding impacts on denitrification are uncharacterised.

Calcium carbonate alters the functional response of coastal sediments to eutrophication-induced acidification.

Coastal ocean acidification research is dominated by laboratory-based studies that cannot necessarily predict real-world ecosystem response given its complexity. We enriched coastal sediments with increasing quantities of organic matter in the field to identify the effects of eutrophication-induced acidification on benthic structure and function, and assess whether biogenic calcium carbonate (CaCO) would alter the response. Along the eutrophication gradient we observed declines in macrofauna biodiversity and impaired benthic net primary productivity and sediment nutrient cycling.

In situ response of Antarctic under-ice primary producers to experimentally altered pH.

Elevated atmospheric CO concentrations are contributing to ocean acidification (reduced seawater pH and carbonate concentrations), with potentially major ramifications for marine ecosystems and their functioning. Using a novel in situ experiment we examined impacts of reduced seawater pH on Antarctic sea ice-associated microalgal communities, key primary producers and contributors to food webs. pH levels projected for the following decades-to-end of century (7.

Sediment carbon and nutrient fluxes from cleared and intact temperate mangrove ecosystems and adjacent sandflats.

The loss of mangrove ecosystems is associated with numerous impacts on coastal and estuarine function, including sediment carbon and nutrient cycling. In this study we compared in situ fluxes of carbon dioxide (CO) from the sediment to the atmosphere, and fluxes of dissolved inorganic nutrients and oxygen across the sediment-water interface, in intact and cleared mangrove and sandflat ecosystems in a temperate estuary. Measurements were made 20 and 25months after mangrove clearance, in summer and winter, respectively.

Changes in the location of biodiversity-ecosystem function hot spots across the seafloor landscape with increasing sediment nutrient loading.

Declining biodiversity and loss of ecosystem function threatens the ability of habitats to contribute ecosystem services. However, the form of the relationship between biodiversity and ecosystem function (BEF) and how relationships change with environmental change is poorly understood. This limits our ability to predict the consequences of biodiversity loss on ecosystem function, particularly in real-world marine ecosystems that are species rich, and where multiple ecosystem functions are represented by multiple indicators.

Same pattern, different mechanism: Locking onto the role of key species in seafloor ecosystem process.

Seafloor biodiversity is a key mediator of ecosystem functioning, but its role is often excluded from global budgets or simplified to black boxes in models. New techniques allow quantification of the behavior of animals living below the sediment surface and assessment of the ecosystem consequences of complex interactions, yielding a better understanding of the role of seafloor animals in affecting key processes like primary productivity. Combining predictions based on natural history, behavior of key benthic species and environmental context allow assessment of differences in functioning and process, even when the measured ecosystem property in different systems is similar.

Effects of Detrital Subsidies on Soft-Sediment Ecosystem Function Are Transient and Source-Dependent.

Detrital subsidies from marine macrophytes are prevalent in temperate estuaries, and their role in structuring benthic macrofaunal communities is well documented, but the resulting impact on ecosystem function is not understood. We conducted a field experiment to test the effects of detrital decay on soft-sediment primary production, community metabolism and nutrient regeneration (measures of ecosystem function). Twenty four (2 m(2)) plots were established on an intertidal sandflat, to which we added 0 or 220 g DW m(-2) of detritus from either mangroves (Avicennia marina), seagrass (Zostera muelleri), or kelp (Ecklonia radiata) (n = 6 plots per treatment).

Detecting Subtle Shifts in Ecosystem Functioning in a Dynamic Estuarine Environment.

Identifying the effects of stressors before they impact ecosystem functioning can be challenging in dynamic, heterogeneous 'real-world' ecosystems. In aquatic systems, for example, reductions in water clarity can limit the light available for photosynthesis, with knock-on consequences for secondary consumers, though in naturally turbid wave-swept estuaries, detecting the effects of elevated turbidity can be difficult. The objective of this study was to investigate the effects of shading on ecosystem functions mediated by sandflat primary producers (microphytobenthos) and deep-dwelling surface-feeding macrofauna (Macomona liliana; Bivalvia, Veneroida, Tellinidae).

The up-scaling of ecosystem functions in a heterogeneous world.

Earth is in the midst of a biodiversity crisis that is impacting the functioning of ecosystems and the delivery of valued goods and services. However, the implications of large scale species losses are often inferred from small scale ecosystem functioning experiments with little knowledge of how the dominant drivers of functioning shift across scales. Here, by integrating observational and manipulative experimental field data, we reveal scale-dependent influences on primary productivity in shallow marine habitats, thus demonstrating the scalability of complex ecological relationships contributing to coastal marine ecosystem functioning.

Experimenting with ecosystem interaction networks in search of threshold potentials in real-world marine ecosystems.

Thresholds profoundly affect our understanding and management of ecosystem dynamics, but we have yet to develop practical techniques to assess the risk that thresholds will be crossed. Combining ecological knowledge of critical system interdependencies with a large-scale experiment, we tested for breaks in the ecosystem interaction network to identify threshold potential in real-world ecosystem dynamics. Our experiment with the bivalves Macomona liliana and Austrovenus stutchburyi on marine sandflats in New Zealand demonstrated that reductions in incident sunlight changed the interaction network between sediment biogeochemical fluxes, productivity, and macrofauna.