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Background and Aims Freshwater nitrogen inputs are increasing globally, altering the structure and function of wetland ecosystems adapted to low nutrient conditions. Carnivorous wetland plants of the genus Utricularia are hypothesized to reduce their reliance on carnivory and increase their assimilation of environmental nutrients when the supply of ambient nutrients increases. Despite success in using stable isotope approaches to quantify carnivory of terrestrial carnivorous plants, quantifying carnivory of aquatic Utricularia requires improvement. Methods We developed stable isotope mixing models to quantify aquatic plant carnivory and used these models to measure dietary changes of three Utricularia species, Utricularia australis , U. gibba and U. uliginosa , in 11 wetlands across a 794-km gradient in eastern Australia. Diet was assessed using multiple models that compared variations in the natural-abundance nitrogen isotope composition (δ15N) of Utricularia spp. with that of non-carnivorous plants, and environmental and carnivorous nitrogen sources. Key Results Carnivory supplied 40–100 % of plant nitrogen. The lowest carnivory rates coincided with the highest availability of ammonium and dissolved organic carbon. Conclusions Our findings suggest that Utricularia populations may adapt to high nutrient environments by shifting away from energetically costly carnivory. This has implications for species conservation as anthropogenic impacts continue to affect global wetland ecosystems. [ABSTRACT FROM AUTHOR]

While the idea of a named language as a separate and discrete identity is a political and social construct, in the cases of Sardinian and Asturian doubts over their respective 'languageness' have real material consequences, particularly in relation to language policy decisions at the state level. The Asturian example highlights how its lack of official status means that it is either ignored or subjected to repeated challenges to its status as a language variety deserving of recognition and support, reflecting how 'official language' in the Spanish context is often understood in practice as synonymous with the theoretically broader category of 'language'. In contrast, the recent state recognition of Sardinian speakers as a linguistic minority in Italy (Law 482/1999) illustrates how legal recognition served to overcome existing obstacles to the implementation of regional language policy measures. At the same time, the limited subsequent effects of this Law, particularly in the sphere of education, are a reminder of the shortcomings of top-down policies which fail to engage with the local language practices and attitudes of the communities of speakers recognized. The contrastive focus of this article thus acknowledges the continued material consequences of top-down language classification, while highlighting its inadequacies as a language policy mechanism which reinforces artificial distinctions between speech varieties and speakers deserving of recognition.

Stable isotope ratios of nitrogen and oxygen (15N/14N and 18O/16O) of nitrate (NO3–) are excellent tracers for developing systematic understanding of sources, conversions, and deposition of reactive atmospheric nitrogen (Nr) in the environment. Despite recent analytical advances, standardized sampling of NO3–) isotopes in precipitation is still lacking. To advance atmospheric studies on Nr species, we propose best-practice guidelines for accurate and precise sampling and analysis of NO3– isotopes in precipitation based on the experience obtained from an international research project coordinated by the International Atomic Energy Agency (IAEA). The precipitation sampling and preservation strategies yielded a good agreement between the NO3– concentrations measured at the laboratories of 16 countries and at the IAEA. Compared to conventional methods (e.g., bacterial denitrification), we confirmed the accurate performance of the lower cost Ti(III) reduction method for isotope analyses (15N and 18O) of NO3– in precipitation samples. These isotopic data depict different origins and oxidation pathways of inorganic nitrogen. This work emphasized the capability of NO3– isotopes to assess the origin and atmospheric oxidation of Nr and outlined a pathway to improve laboratory capability and expertise at a global scale. The incorporation of other isotopes like 17O in Nr is recommended in future studies. [ABSTRACT FROM AUTHOR]

In this article, the editors introduce the Digital Modern Languages Special Collection that results from an open call that sought out new and emerging research at the intersection of Modern Languages and digital culture, media and technologies. They explain the intentionally wide-ranging and transdisciplinary scope of the Collection, which reflects an openness to the many ways Digital Modern Languages research is practised. The Collection also includes research on a wide range of geographical and linguistic contexts, reflecting wider calls to move beyond the limited range of languages traditionally associated with "Modern Languages". Through this combined transdisciplinary and cross-languages focus, the Collection seeks to contribute to the broader strategic identity transformation of the wider field. [ABSTRACT FROM AUTHOR]

Estuaries play an important role in regulating nitrous oxide (N2O) fluxes to the atmosphere, but little is known about how catchment land‐use changes influence benthic N2O cycling. We measured seasonal benthic N2O fluxes and constructed N2O budgets in three sub‐tropical estuaries draining catchments with contrasting levels of land‐use intensity. Benthic habitats were a net N2O sink in the minimally impacted Noosa River Estuary (−287 nmol m−2 h−1) and a net source of N2O in the highly impacted Brisbane River Estuary (126 nmol m−2 h−1). Vegetated habitats can act as an important sink of N2O with uptakes of −286 and −35 nmol m−2 h−1 in the Noosa and Maroochy River Estuaries, respectively. Benthic N2O fluxes were significantly correlated with benthic NO3− fluxes, suggesting NO3− availability was an important control on benthic N2O fluxes. Combining benthic flux data with surface water N2O emissions measurements showed that increased benthic N2O fluxes helped drive increasing water–air N2O emissions over the land‐use intensity gradient. Overall, our results show that land‐use driven changes to both the diversity and sediment composition of benthic habitats play an important role in regulating N2O dynamics in estuarine ecosystems. This highlights that both sediment quality and nitrogen loading need to be considered in order to reduce emissions of greenhouse gases in the coastal ecosystems. Plain Language Summary: Nitrous oxide (N2O) is the third most important long‐lived greenhouse gas that accumulates in the atmosphere. Increasing land‐use intensities such as intensifying agricultural production and coastal urbanization deposit large amounts of anthropogenic nitrogen (N) into estuarine ecosystems, which in‐turn increases estuarine N2O production. To date most studies have focused on the impacts of land‐use change on water column N2O emissions, or benthic N2O cycling, with very few looking at both compartments simultaneously. In this study, we measured benthic N2O fluxes together with water–air N2O fluxes in three sub‐tropical estuaries across a land‐use gradient. We find that benthic sediments can uptake N2O under low land‐use intensity, while increased land‐use intensity can switch benthic sediments from net consumers to produces of N2O, potentially accelerating whole‐estuary N2O emissions. This is an important finding as benthic sediments play an important functional link between estuarine ecosystems. Key Points: Estuary sediments switch from sinks to sources of N2O with increasing land‐use intensityVegetated coastal habitats can act as a sink of N2ONO3− availability was the important control on benthic N2O fluxes [ABSTRACT FROM AUTHOR]

Estuaries make an important contribution to the global greenhouse gas budget. Yet modeling predictions of carbon dioxide (CO2) and methane (CH4) emissions from estuaries remain highly uncertain due to both simplified assumptions about the underpinning hydrologic and biologic processes and inadequate data availability to uniquely define parameters related to CO2 and CH4 processes. This study presents a modeling framework to quantify the sensitivity and uncertainty of predicted CO2 and CH4 concentrations and emissions, which is demonstrated through application to a subtropical urban estuary (Brisbane River, Australia). A 3D hydrodynamic‐biogeochemical model was constructed, and calibrated using the model‐independent Parameter ESTimation software (PEST) with field data sets that captured strong gradients of CO2 and CH4 concentrations and emissions along the estuary. The approach refined uncertainty in the estimation of whole‐estuary annual emissions, and enabled us to assess the sensitivity and uncertainty of CO2 and CH4 dynamics. Estuarine CO2 concentrations were most sensitive to uncertainty in riverine inputs, whereas estuarine CH4 concentrations were most sensitive to sediment production and pelagic oxidation. Over the modeled year, variance in the daily fluctuations in carbon emissions from this case‐study spanned the full range of emission rates reported for estuaries around the world, highlighting that spatially or temporally limited sampling regimes could significantly bias estuarine greenhouse gas emission estimates. The combination of targeted field campaigns with the modeling approach presented in this study can help to improve carbon budgeting in estuaries, reduce uncertainty in emission estimates, and support management strategies to reduce or offset estuary greenhouse gas emissions. Plain Language Summary: Global estuaries are a major source of CO2 emission and play a disproportionate role in global carbon cycling relative to their area. Estuaries are also a source of CH4 that has approximately 34 times the global‐warming potential of CO2 over a 100‐year time period. However, large uncertainties remain in estimating the CO2 and CH4 emissions from estuaries due to limited observations to cover their large spatiotemporal variations, and lack of knowledge of their dynamics in response to the external inputs and internal biogeochemical reactions. In this study, we developed a modeling framework to address the sensitivity and uncertainty of CO2 and CH4 dynamics in the Brisbane River Estuary to both the riverine and wastewater inputs and biogeochemical reaction parameters. We showed that CO2 concentrations were most sensitive to catchment inputs and CH4 concentrations were most sensitive to the rate of sediment production and oxidation in the water. The estimated annual‐total CO2 equivalent emission from Brisbane River Estuary in 2016 was 3,514 ± 445 tonnes. The combination of targeted field campaigns with the modeling approach can help to improve carbon budgeting in estuaries, reduce uncertainty in emission estimates, and support management strategies to reduce or offset estuary greenhouse gas emissions. Key Points: Estuarine CO2 is most sensitive to external riverine CO2 inputsEstuarine CH4 is most sensitive to sediment production and oxidation in the waterThe modeling approach constrained the uncertainty in the estimation of CO2 and CH4 outgassing [ABSTRACT FROM AUTHOR]