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Abstract Lowland tropical forest soils are relatively N rich and are the largest global source of N₂O (a powerful greenhouse gas) to the atmosphere. Despite the importance of tropical N cycling, there have been few direct measurements of N₂(an inert gas that can serve as an alternate fate for N₂O) in tropical soils, limiting our ability to characterize N budgets, manage soils to reduce N₂O production, or predict the future role that N limitation to primary productivity will play in buffering against climate change. We collected soils from across macro‐ and micro‐topographic gradients that have previously been shown to differ in O₂availability and trace gas emissions. We then incubated these soils under oxic and anoxic headspaces to explore the relative effect of soil location versus transient redox conditions. No matter where the soils came from, or what headspace O₂was used in the incubation, N₂emissions dominated the flux of N gas losses. In the macrotopography plots, production of N₂and N₂O were higher in low O₂valleys than on more aerated ridges and slopes. In the microtopography plots, N₂emissions from plots with lower mean soil O₂(5%–10%) were greater than in plots with higher mean soil O₂(10%–20%). We estimate an N gas flux of ∼37 kg N/ha/yr from this forest, 99% as N₂. These results suggest that N₂fluxes may have been systematically underestimated in these landscapes, and that the measurements we present call for a reevaluation of the N budgets in lowland tropical forest ecosystems. 

Soil nitrous oxide (N 2 O) emissions are an important driver of climate change and are a major mechanism of labile nitrogen (N) loss from terrestrial ecosystems. Evidence increasingly suggests that locations on the landscape that experience biogeochemical fluxes disproportionate to the surrounding matrix (hot spots) and time periods that show disproportionately high fluxes relative to the background (hot moments) strongly influence landscape-scale soil N 2 O emissions. However, substantial uncertainties remain regarding how to measure and model where and when these extreme soil N 2 O fluxes occur. High-frequency datasets of soil N 2 O fluxes are newly possible due to advancements in field-ready instrumentation that uses cavity ring-down spectroscopy (CRDS). Here, we outline the opportunities and challenges that are provided by the deployment of this field-based instrumentation and the collection of high-frequency soil N 2 O flux datasets. While there are substantial challenges associated with automated CRDS systems, there are also opportunities to utilize these near-continuous data to constrain our understanding of dynamics of the terrestrial N cycle across space and time. Finally, we propose future research directions exploring the influence of hot moments of N 2 O emissions on the N cycle, particularly considering the gaps surrounding how global change forces are likely to alter N dynamics in the future. 

Gender equity in academia is a long-standing struggle. Although common to all disciplines, the impacts of bias and stereotypes are particularly pronounced in science, technology, engineering and mathematics (STEM) disciplines. This paper explores what barriers exist for the career progression of women in academia in STEM disciplines in order to identify key issues and potential solutions. In particular, we were interested in how women perceive the barriers affecting their careers in comparison to their male colleagues. Fourteen focus groups with female-identifying academics showed that there were core barriers to career progression, which spanned countries, disciplines and career stages. Entrenched biases, stereotypes, double standards, bullying and harassment all negatively impact women’s confidence and sense of belonging. Women also face an additional biological burden, often being pushed to choose between having children or a career. Participants felt that their experiences as STEM academics were noticeably different to those of their male colleagues, where many of the commonly occurring barriers for women were simply non-issues for men. The results of this study indicate that some of these barriers can be overcome through networks, mentoring and allies. Addressing these barriers requires a reshaping of the gendered norms that currently limit progress to equity and inclusion. 

Abstract Gender biases and stereotypes are prevalent in science, technology, engineering and mathematics (STEM) fields, which can create obstacles for the attraction, retention and progression of girls and women to STEM studies and careers. There are many initiatives which are used to attempt to address these biases and stereotypes, including the use of visible role models. This study explores the perceptions of the stereotypes applied to female STEM professionals who publicly speak about their work in both academic and non-academic settings. Using workshops with over 300 participants, predominantly female STEM professionals, from over 25 different cultural backgrounds, the results showed women who publicly communicate their work are likely to be stereotyped as ‘bitchy’, ‘bossy’, and ‘emotional’—often by their own gender. These findings suggest that women may be in a more vulnerable position when communicating publicly about their work, which could have implications for them participating fully in their careers. It may also have implications for programs which use role models to address prevailing STEM stereotypes. Systematic cultural and institutional change is needed in STEM fields to address the underlying bias and negative stereotypes facing women. However, it should be ensured that the intended solutions to facilitate this change are not compounding the problem. 

Coastal ecosystems display consistent patterns of trade-offs between resistance and resilience to tropical cyclones. 

Abstract Tropical cyclones play an increasingly important role in shaping ecosystems. Understanding and generalizing their responses is challenging because of meteorological variability among storms and its interaction with ecosystems. We present a research framework designed to compare tropical cyclone effects within and across ecosystems that: a) uses a disaggregating approach that measures the responses of individual ecosystem components, b) links the response of ecosystem components at fine temporal scales to meteorology and antecedent conditions, and c) examines responses of ecosystem using a resistance–resilience perspective by quantifying the magnitude of change and recovery time. We demonstrate the utility of the framework using three examples of ecosystem response: gross primary productivity, stream biogeochemical export, and organismal abundances. Finally, we present the case for a network of sentinel sites with consistent monitoring to measure and compare ecosystem responses to cyclones across the United States, which could help improve coastal ecosystem resilience.