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This paper presents a methodology to evaluate life safety risk of coastal communities vulnerable to seismic and tsunami hazards. The work explicitly incorporates two important aspects in tsunami evacuation modeling: (1) the effect of earthquake-induced damage to buildings on building egress time, (2) the effect of earthquake-induced debris on horizontal evacuation time. The city of Seaside, Oregon, is selected as a testbed community. The hazard is based on a megathrust earthquake and tsunami from the Cascadia Subduction Zone that was defined in a previous study. The built environment consists of buildings and the transportation network for the city. Fragility analysis is used to estimate the seismic damage to buildings and resulting debris that covers portions of the road network. The horizontal evacuation time is determined based on the shortest path to shelters, including the increased travel time due to the earthquake-generated debris. The effects of different mitigation strategies are quantified. Results indicate the fatality and life safety risk of a near-field tsunami increases by 4.2–8.3 times when the effects of building egress and earthquake-induced debris are considered. The choice of population layer affects the life safety risk and thus the maximum risk is obtained when daytime populations are considered. Use of mitigation strategies result in a significant decrease in the number of fatalities. For hazards with recurrence intervals larger than 500- to 1000-years, the seismic retrofit is comparable to vertical evacuation and an effective strategy in reducing fatalities and associated risks. Implementing all mitigation strategies reduces the life safety risk by 90%. [ABSTRACT FROM AUTHOR]

Access after disasters to resources such as food poses planning problems that affect millions of people each year. Understanding how disasters disrupt and alter food access during the initial steps of the recovery process provides new evidence to inform both food system and disaster planning. Our research took a supply-side focus and explored the results from a survey of food retailers after Hurricane Harvey in three Texas counties. The survey collected information on how the disaster affected a store's property, people, and products and the length of time a store was closed, had reduced hours, and stopped selling fresh food items. We found that a focus only on store closures and property damage would underestimate the number of days residents had limited fresh food access by nearly 2 weeks. Further, stores in lower-income communities with chronically low access to supermarkets (food deserts) were closed longer than other stores, potentially compounding pre-existing inequalities. To plan for a more equitable food supply after a disaster, planners should embrace more dimensions of access, encourage retailer mitigation, and assess the types of retailers and their distribution within their communities. Practicing planners aspire to ensure equitable access to resources (e.g., food, education, and health care). In the context of food access, planners should consider that a) common proximity-based measures of accessibility (e.g., food deserts) may underestimate inequality and that the inclusion of multiple dimensions of access may provide a more accurate picture, b) efforts to encourage business resilience can complement food systems planning, and c) targeted engagement with local food retailers, food suppliers, and food aid agencies is important for both day-to-day community needs and for disaster planning. [ABSTRACT FROM AUTHOR]

This paper presents a building‐level post‐hazard functionality model for communities exposed to flood hazards including the interdependencies between the population, buildings, and infrastructure. An existing portfolio of building archetypes is used to model the post‐hazard physical flood functionality of different building typologies within the community with the goal of supporting resilience‐informed decision‐making. Specific fragility‐based flood functionality curves were developed for this portfolio to quantify the exceedance probability of a prescribed set of functionality states. While the physical functionality of buildings is significant to the total functionality of a building and community resilience assessment, the functionality of utilities such as power and water along with the accessibility of the household to essential services such as schools and hospitals is crucial to measure their total functionality. Therefore, functionality models for essential infrastructure were developed to assess housing unit‐ and building‐level functionality following flood hazards. This model also accounts for the functionality of the road network following a flood hazard to identify the level of accessibility of households to different services (e.g., schools, hospitals, gas stations, shopping centers, etc.). The main novelty of this paper is the ability to quantify the total functionality of buildings based on a socio‐physical formulation after including the interdependencies between the functionality of the physical systems and the subsequent functionality of the socio‐economic systems, which is key to measuring resilience at the community level. This was evident from the analysis results using a testbed community of Lumberton, NC, showing that the physical functionality is not sufficient to quantify the total post‐hazard functionality of buildings and that the functionality of other subsystems such as utilities and accessibility to essential services are also needed to quantify the total functionality of buildings and the livability of households. [ABSTRACT FROM AUTHOR]

When reproductive success is determined by the relative availabilities of a series of essential, non‐substitutable resources, the theory of balanced fitness limitations predicts that the cost of harvesting a particular resource shapes the likelihood that a shortfall of that resource will constrain realized fitness. Plant reproduction through female function offers a special opportunity to test this theory; essential resources in this context include, first, the pollen received from pollinators or abiotic vectors that is used to fertilize ovules, and, second, the resources needed to provision the developing seeds and fruit. For many plants realized reproductive success through female function can be readily quantified in the field, and one key potential constraint on fitness, pollen limitation, can be assessed experimentally by manually supplementing pollen receipt. We assembled a comparative dataset of pollen limitation using only studies that supplement pollen to all flowers produced over the plant's reproductive lifespan. Pre‐ and post‐pollination costs were estimated using the weight of flowers and fruits and estimates of fruit set. Consistent with expectations, we find self‐incompatible plants make greater pre‐pollination investments and experience greater pollen limitation. However, contrary to theoretical expectations, when variation due to self‐compatibility is accounted for by including self‐compatibility in the statistical model as a covariate, we find no support for the prediction that plants that invest more heavily in pre‐pollination costs are subject to greater pollen limitation. Strong within‐species, between‐population variation in the expression of pollen limitation makes the quantification of mean pollen limitation difficult. We urge plant ecologists to conduct more studies of pollen limitation using whole‐plant pollen supplementation to produce a richer comparative dataset that would support a more robust test of the balanced limitations hypothesis. [ABSTRACT FROM AUTHOR]

Here we describe the nesting behavior of a previously unstudied solitary groundnesting wasp, Ammophila boharti Menke, 1964. Species in the genus Ammophila are of particular interest because they exhibit a variety of parental care strategies. Ammophila boharti wasps were observed at two California field sites, one in the Mojave Desert and the other at the Antioch Dunes National Wildlife Refuge. Ammophila boharti begins its nesting cycle by hunting for a single, large caterpillar; all prey observed at Antioch Dunes were Neoterpes ephelidaria (Hulst, 1886) (Lepidoptera: Geometridae), which were feeding on California poppies, Eschscholzia californica Cham. (Papaveraceae). Female A. boharti wasps sting the caterpillar, inducing permanent paralysis, and then cache the prey off the soil surface on a plant while they excavate a shallow, unicellular nest. The caterpillar is then placed in the nest, a single egg laid on the caterpillar, and a permanent closure placed on the nest. No nest parasites were seen at any stage of the nesting process, and offspring within all excavated nests developed successfully through the larval stages to spin cocoons. Thus, this species exhibits a 'prey-nest' sequence of nesting behavior with almost no contact between the mother and her offspring, a minority condition within the genus. [ABSTRACT FROM AUTHOR]

Blue carbon ecosystems such as mangroves and salt marshes store large amounts of carbon (C) in the form of plant biomass and soils that are often rich in organic matter. These C stocks have a high degree of spatial variability within and among coastal wetland ecosystem types, but quantifying location-specific C stocks is both labor intensive and time-consuming. Above- and belowground C stock data were compiled from field efforts in Southwest Florida and from published georeferenced C data. These data were used in conjunction with ecosystem maps, remote-sensing parameters, and existing vegetation models to create 30-m resolution spatial models quantifying aboveground C stocks and belowground C stocks up to 1-m depth in mangroves and salt marshes along 360 km of coast in Southwest Florida (Tampa Bay to the Everglades). Based on modeling results, mangroves and salt marshes in Southwest Florida store an average of 393.9 ± 107.1 and 286.7 ± 71.9 Mg C ha−1, respectively, in above- and belowground C stocks. Soil C density and belowground C stocks increased at lower latitudes within the study region. Total C stocks in mangroves increased from 265.1 ± 43.2 Mg ha−1 in Tampa Bay and Sarasota Bay to 409 ± 104.4 Mg ha−1 in the Everglades. Substrate stability and C stocks are susceptible to impacts from climate change, sea-level rise, hydrologic changes, and episodic disturbances such as tropical cyclones. The long-term storage of C in these ecosystem types depends on ecosystem stability in the face of these stressors. [ABSTRACT FROM AUTHOR]

Food pantries play a growing role in supporting households facing or at risk of food insecurity in the United States. They also support emergency response and recovery following disasters and extreme weather events. Although food pantries are often placed in close proximity to communities with the highest rates of poverty and risk of food insecurity, access to these facilities can be disrupted during and after extreme events. Decreased access to food pantries following disasters can be particularly problematic as the need for these services is also likely to grow after such events. Despite the vast body of research on food retail access and food environments, relatively little research has utilized spatial analysis to understand food pantry access, particularly after extreme events. Using Geographic Information Systems (GIS), we characterize changes in access to food pantries following flooding events in Harris County, Texas—a highly populated and flood prone region with high levels of food insecurity and poverty. Specifically, our study models disruptions in road networks due to flooding and assesses the impacts of these disruptions on proximity to food pantries. The results reveal that much of Harris County sees only small increases in travel distance to food pantries due to extreme flooding, but some areas may be unable to access food pantries at all. This research highlights the potential and some of the limits of private food assistance networks to support emergency response efforts. [ABSTRACT FROM AUTHOR]

During the 2018–2019 Antarctic field season, the Subglacial Antarctic Lakes Scientific Access project team cleanly accessed Mercer Subglacial Lake, West Antarctica, to sample water and sediments beneath 1087 m of overlying ice. A multicorer was successful in sampling the sediment–water interface, with 4 deployments retrieving 10 cores between 0.3 and 0.4 m in length. Gravity coring was also successful, retrieving cores of 0.97 and 1.78 m in glacial diamict. However, sediment cores retrieved by the gravity cores were shorter than the core barrel penetration (as measured by mud streaks on the outside of the coring system), indicating that the system can likely be improved. This manuscript describes the design, implementation, successes, and lessons learned while coring sediments in a subglacial lake. [ABSTRACT FROM AUTHOR]

The behavioral phenotypes of hosts may be altered during parasitism, which could favor either the host or the parasite. Pea aphid Acyrthosiphon pisum hosts parasitized by the primary parasitoid wasp Aphidius ervi leave the stems or lower leaf surfaces where they are most commonly found and move to upper leaf surfaces before they die and mummify. In order to test whether the change of microhabitat benefits the host or the parasitoid, we transplanted pea aphid mummies reared in the laboratory to three different microhabitats on alfalfa plants in the field: the upper leaf surfaces, the lower leaf surfaces, and the stems. Survival analysis revealed no significant differences in mummy survival to emergence across the microhabitat treatments before an alfalfa harvest, when predation pressure was very high, and 2 weeks after an alfalfa harvest, when predation pressure was very low. In contrast, 5 weeks after an alfalfa harvest, when predation pressure was intermediate differences in predation risk were apparent: mummies transplanted to the upper leaf surface had the lowest mortality rates, mummies transplanted to the lower surface of leaves had intermediate mortality rates, and mummies transplanted to the stems had the highest mortality rates. Furthermore, a laboratory study suggested that, compared to other plant substrates, mummies on stems were more likely to be preyed upon by the ladybeetle, Hippodamia convergens, which concentrated its search on stems. Our results support the adaptive manipulation hypothesis, in that parasitized aphids appear to induce their host to move to a region of reduced predator foraging, where their risk of attack is reduced. [ABSTRACT FROM AUTHOR]

Sexual harassment is a pervasive problem on oceanographic research vessels and while conducting fieldwork in general. A variety of factors contribute to inadequate protection against sexual harassment, such as poor training in prevention, support, and response; remoteness of field sites; academic hierarchies that reinforce uneven power dynamics that extend to fieldwork; and multi-institutional teams with distinct policies or reporting structures that can lead to confusion in reporting and responding to incidents in the field. In compromising individuals' physical and mental health, sexual harassment can negatively affect research expeditions. For example, harassed individuals may decide to refrain from working on complicated teambased tasks, which can be a safety issue. A broader concern is that sexual harassment deters talented people from pursing or maintaining employment in ocean science. Harassment must be treated with the same gravity as research misconduct and safety policy infringements. When planning a research expedition, science team leaders are responsible for the safety of their team and other colleagues aboard and would benefit from resources aimed at helping team leadership create a plan to ensure safety and inclusivity. To address this resource gap, 18 participants in the Workshop to Promote Field Safety in Ocean Sciences, convened by the Consortium for Ocean Leadership and held May 17-18, 2022, in Washington, DC, developed a checklist for use by scientific leaders and others to assist in planning for participant safety and to prevent harassment the field. The checklist specifies the timing of, and who is responsible for, specific actions that should be taken to improve safety while conducting fieldwork, whether on a research vessel or on land. It also provides additional resources and suggestions for leaders on how to amend the checklist to address their specific fieldwork situations. [ABSTRACT FROM AUTHOR]

Deep-sea corals have the potential to provide high resolution paleotemperature records to evaluate oceanographic changes in settings that are vulnerable to current and future warming. The geochemical records preserved in coral skeletal carbonate, however, are limited by their large offsets from isotopic equilibrium with seawater. These "vital effects" are the result of biological influences (kinetic and metabolic) on the calcification of coral skeletons and are well known to drive oxygen and carbon stable isotope ratios (d18O and d13C, respectively) away from an environmental signal. Additionally, vital effects as they pertain to deep-sea branching corals are not well understood, thus hindering the utility of paleoceanographic archives with a vast latitudinal range. Here we describe the likely growth structure of a deep-sea stylasterid coral taxon and demonstrate the optimal sampling location for paleotemperature reconstructions. We sampled two coral specimens over cross sections through their primary growth axes to create skeletal d18O and d13C maps. Such maps reveal a consistent trend of increasing isotopic values toward the innermost portion of the coral slices; the average center values being ~1‰ closer to seawater equilibrium values than a traditional bulk sample. The difference between the higher center and lower bulk d18O values result in temperature difference as much as 5.1° C (±1.8° C) between the sampling methods. These results support a two-step biomineralization consisting of a rapid initial skeletal construction, followed by a slower infilling concentrated towards the center, not yet described for this coral taxon. We anticipate this work to initiate efforts to sample deep-sea branching corals, potentially informing advanced visualization techniques to achieve the most accurate paleotemperature reconstructions. [ABSTRACT FROM AUTHOR]

Cannibalism, once viewed as a rare or aberrant behavior, is now recognized to be widespread and to contribute broadly to the self‐regulation of many populations. Cannibalism can produce endogenous negative feedback on population growth because it is expressed as a conditional behavior, responding to the deteriorating ecological conditions that flow, directly or indirectly, from increasing densities of conspecifics. Thus, cannibalism emerges as a strongly density‐dependent source of mortality. In this synthesis, we review recent research that has revealed a rich diversity of pathways through which rising density elicits increased cannibalism, including both factors that (a) elevate the rate of dangerous encounters between conspecifics and (b) enhance the likelihood that such encounters will lead to successful cannibalistic attacks. These pathways include both features of the autecology of cannibal populations and features of interactions with other species, including food resources and pathogens. Using mathematical models, we explore the consequences of including density‐dependent cannibal attack rates on population dynamics. The conditional expression of cannibalism generally enhances stability and population regulation in single‐species models but also may increase opportunities for alternative states and prey population escape from control by cannibalistic predators. [ABSTRACT FROM AUTHOR]

Variability in population densities is key to the ecology of natural systems but also has great implications for agriculture. Farmers' decisions are heavily influenced by their risk aversion to pest outbreaks that result in major yield losses. However, the need for long‐term pest population data across many farms has prevented researchers from exploring the drivers and implications of pest population variability (PV). Here, we demonstrate the critical importance of PV for sustainable farming by analyzing 13 years of pest densities across >1300 Spanish olive groves and vineyards. Variable populations were more likely to cause major yield losses, but also occasionally created temporal windows when densities fell below insecticide spray thresholds. Importantly, environmental factors regulating pest variability were very distinct from factors regulating mean density, suggesting variability needs to be uniquely managed. Finally, we found diversifying landscapes may be a win–win situation for conservation and farmers, as diversified landscapes promote less abundant and less variable pest populations. Therefore, we encourage agricultural stakeholders to increase the complexity of the landscapes surrounding their farms through conserving/restoring natural habitat and/or diversifying crops. [ABSTRACT FROM AUTHOR]

Agricultural plant species differ in susceptibility to herbivores; therefore, identifying natural resistances or tolerances to pests can be leveraged to develop preventative, integrated pest management approaches. While many Citrus species are grown in California, most pest management guidelines are based upon research conducted on navel oranges [ Citrus sinensis (L.) Osbeck; Sapindales: Rutaceae]. A recent study has established European earwigs (Forficula auricularia L.; Dermaptera: Forficulidae) as herbivores of young navel orange fruit, causing damage ranging from small bite marks to large chewed holes. It is unknown whether earwigs damage fruit of other citrus species. We conducted field experiments in which we caged earwigs to branch terminals bearing young fruit to explore potential differences in susceptibility of Citrus species to European earwigs. Specifically, we tested whether three species, navel oranges, clementines (C. clementina hort. ex Tanaka), and true mandarins (C. reticulata Blanco) exhibit differences in: 1) feeding deterrence to earwigs; 2) suitability as food for earwigs; 3) preferential abscission of damaged fruit; and 4) healing of damaged fruit. Earwigs caused heavy damage on navel orange and clementine fruit, whereas heavy damage was rare on true mandarin fruit. There was little evidence of preferential abscission of damaged fruit or healing of seriously damaged fruit. Consequently, several heavily damaged navel orange and one clementine fruit were retained to harvest and developed large scars. Overall, we found that Citrus fruit vary in their susceptibility to earwigs, and pest management strategies for earwigs should be refined to consider their varying effects on different Citrus species. [ABSTRACT FROM AUTHOR]

Individuals with potential exposure to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) do not necessarily develop PCR or antibody positivity, suggesting that some individuals may clear subclinical infection before seroconversion. T cells can contribute to the rapid clearance of SARS-CoV-2 and other coronavirus infections1–3. Here we hypothesize that pre-existing memory T cell responses, with cross-protective potential against SARS-CoV-2 (refs. 4–11), would expand in vivo to support rapid viral control, aborting infection. We measured SARS-CoV-2-reactive T cells, including those against the early transcribed replication–transcription complex (RTC)12,13, in intensively monitored healthcare workers (HCWs) who tested repeatedly negative according to PCR, antibody binding and neutralization assays (seronegative HCWs (SN-HCWs)). SN-HCWs had stronger, more multispecific memory T cells compared with a cohort of unexposed individuals from before the pandemic (prepandemic cohort), and these cells were more frequently directed against the RTC than the structural-protein-dominated responses observed after detectable infection (matched concurrent cohort). SN-HCWs with the strongest RTC-specific T cells had an increase in IFI27, a robust early innate signature of SARS-CoV-2 (ref. 14), suggesting abortive infection. RNA polymerase within RTC was the largest region of high sequence conservation across human seasonal coronaviruses (HCoV) and SARS-CoV-2 clades. RNA polymerase was preferentially targeted (among the regions tested) by T cells from prepandemic cohorts and SN-HCWs. RTC-epitope-specific T cells that cross-recognized HCoV variants were identified in SN-HCWs. Enriched pre-existing RNA-polymerase-specific T cells expanded in vivo to preferentially accumulate in the memory response after putative abortive compared to overt SARS-CoV-2 infection. Our data highlight RTC-specific T cells as targets for vaccines against endemic and emerging Coronaviridae.Seronegative healthcare workers with an innate signature of infection preferentially expand pre-existing T cells targeting the conserved replication transcription complex of SARS-CoV-2 in abortive infection. [ABSTRACT FROM AUTHOR]

This paper presents a methodology that generates and links high-resolution spatial data on households and housing units with heterogeneous characteristics (i.e., size, tenure status, occupied, and vacant) to residential buildings which in turn are linked to critical infrastructure. The methodology utilizes areal demographic data from the US Census, which are probabilistically linked to an inventory of housing units located in residential buildings. By allocating high-resolution household socio-demographic data to housing units in single and multi-family residential structures themselves linked to critical infrastructure systems, coupled engineering-social science modeling is possible. This paper presents a workflow for linking social science and engineering data to enable integrated models for community resilience. The methodology is applied to Seaside, Oregon, a coastal community with a year-round population of over 6,000 persons. The application highlights the benefits of integrating social science and engineering data. Benefits include facilitating coupled modeling, accounting for uncertainty, visualization, and spatial exploration of modeled results. [ABSTRACT FROM AUTHOR]

Tornadoes occur at a high frequency in the United States compared with other natural hazards but have a substantially small footprint. A single high-intensity tornado can result in high casualty rates and catastrophic economic and social consequences, particularly for small- to medium-size communities. Comprehensive community resilience assessment and improvement requires the analyst to develop a model of interacting physical, social, and economic systems and to measure outcomes that result from specific decisions made. These outcomes often are in the form of metrics such as the number of people injured or the number of households and/or businesses without water, but it has been recognized that most community resilience metrics have socioeconomic characteristics. In this study, for the first time, a fully quantitative interacting model is used to examine the effect of a tornado damaging physical infrastructure (buildings and electrical power network) and the effects on the population and the local economy for a real community. Then, three residential building retrofit strategies are considered as alternatives to improve community resilience, and the metrics for the physical, economic, and social sectors are computed. An illustrative example is presented for the 2011 Joplin tornado in a new open-source Interdependent Networked Community Resilience Modeling Environment (IN-CORE), with a computable general equilibrium (CGE) economics model that computes household income, employment, and domestic supply before and after the tornado. Detailed demographic data was allocated to each structure to enable the calculation of resilience metrics related to population dislocation impacts from the tornado. The results of these analyses stemming from building damage estimation have a logical trend, but the substantial contribution of this work is that, for the first time, the effect of retrofit strategies for tornado loading can be quantified in terms of their effects on socioeconomic metrics. [ABSTRACT FROM AUTHOR]

Background: Yellow fever vaccine (YFV) is not advised for multiple sclerosis (MS) patients because of the potential risk of post-vaccine relapses. Objective: To assess the risk of relapsing-remitting multiple sclerosis (RR-MS) worsening after YFV. Methods: Non-interventional observational retrospective, exposed/non-exposed cohort study nested in the French national cohort including MS. Results: 128 RR-MS were included. The 1-year annualized relapse rate (ARR) following YFV did not differ between exposed: 0.219 (0.420) and non-exposed subjects: 0.208 (0.521) (p = 0.92). Time to first relapse was not different between groups (adjusted hazard ratio (HR) = 1.33; 95% confidence interval (CI) = 0.53–3.30, p = 0.54). Conclusion: These results suggest that YFV does not worsen the course of RR-MS. [ABSTRACT FROM AUTHOR]

Background and purpose: This study was undertaken to validate a clinical score of vascular origin in patients with acute transient visual disturbances (TVDs) without diplopia. Methods: We conducted a prospective study in an ophthalmology emergency department and a transient ischemic attack (TIA) clinic. Patients underwent clinical evaluation including a tailored questionnaire, brain, vascular, and ophthalmologic investigations, and 3‐month follow‐up. TVDs were classified according to vascular or nonvascular origin by three independent experts based on all clinical, cerebrovascular, and ophthalmologic investigations, but blind to the questionnaire results. A clinical score was derived based on clinical variables independently associated with a vascular origin, and was externally validated in an independent cohort. Results: An ischemic origin of TVD was found in 45% (67/149) of patients in the derivation cohort. Age and six questions were independently associated with an ischemic origin. A nine‐point score (≥70 years old = 2; monocular visual loss = 2; black or white vision = 1; single episode = 1; lack of headache = 2; diffuse, constricted, altitudinal, or lateralized visual loss pattern on drawings = 1) showed good discriminative power in identifying ischemic origin (c‐statistic = 0.82) and was replicated in the validation cohort (n = 130, 25% of ischemic origin, c‐statistic = 0.75). With a score ≥ 4, sensitivity was 85% (95% confidence interval = 68−95) and specificity was 52% (95% confidence interval = 41−62). In both cohorts, ophthalmologic evaluation found a vascular cause in 4% and was noncontributive in 85%. After 3 months, no patients had a stroke, TIA, or retinal infarct. Conclusions: Our score may assist in predicting a vascular origin of TVD. Ophthalmologic evaluation, when not readily available, should not delay the neurovascular evaluation. [ABSTRACT FROM AUTHOR]

This paper presents a methodology to deaggregate the results of a multi-hazard damage analysis by extending the traditional multi-hazard damage analysis to consider both population characteristics and independent hazards. The methodology is applied to the joint seismic-tsunami hazard at Seaside, Oregon, considering four infrastructure systems: (1) buildings, (2) transportation network, (3) electric power network and (4) water supply network. Damages to all infrastructure systems are evaluated, and the networked infrastructures are used to inform parcel connectivity to critical facilities. US Census data and a probabilistic housing unit allocation method are implemented to assign detailed household demographic characteristics at the parcel level. Six dimensions of deaggregation are introduced: (1) spatial, (2) hazard type, (3) hazard intensity, (4) infrastructure system, (5) infrastructure component, and (6) housing unit characteristics. The damages, economic losses and risks, and connectivity to critical facilities are deaggregated across these six dimensions. The results show that deaggregated economic loss and risk plots can allow community resilience planners the ability to isolate high-risk events, as well as provide insights into the underlying driving forces. Geospatial representation of the results allows for the identification of both vulnerable buildings and areas within a community and is highlighted by the spatial pattern of parcel disconnection from critical facilities. The incorporation of population characteristics provides an understanding of how hazards disproportionately impact population subgroups and can aide in equitable resilience planning. [ABSTRACT FROM AUTHOR]

Radiocarbon (14C) is an isotopic tracer used to address a wide range of scientific research questions. However, contamination by elevated levels of 14C is deleterious to natural-level laboratory workspaces and accelerator mass spectrometer facilities designed to precisely measure small amounts of 14C. The risk of contaminating materials and facilities intended for natural-level 14C with elevated-level 14C-labeled materials has dictated near complete separation of research groups practicing profoundly different measurements. Such separation can hinder transdisciplinary research initiatives, especially in remote and isolated field locations where both natural-level and elevated-level radiocarbon applications may be useful. This paper outlines the successful collaboration between researchers making natural-level 14C measurements and researchers using 14C-labeled materials during a subglacial drilling project in West Antarctica (SALSA 2018–2019). Our strict operating protocol allowed us to successfully carry out 14C labeling experiments within close quarters at our remote field camp without contaminating samples of sediment and water intended for natural level 14C measurements. Here we present our collaborative protocol for maintaining natural level 14C cleanliness as a framework for future transdisciplinary radiocarbon collaborations. [ABSTRACT FROM AUTHOR]

The Subglacial Antarctic Lakes Scientific Access (SALSA) Project accessed Mercer Subglacial Lake using environmentally clean hot-water drilling to examine interactions among ice, water, sediment, rock, microbes and carbon reservoirs within the lake water column and underlying sediments. A ~0.4 m diameter borehole was melted through 1087 m of ice and maintained over ~10 days, allowing observation of ice properties and collection of water and sediment with various tools. Over this period, SALSA collected: 60 L of lake water and 10 L of deep borehole water; microbes >0.2 μm in diameter from in situ filtration of ~100 L of lake water; 10 multicores 0.32–0.49 m long; 1.0 and 1.76 m long gravity cores; three conductivity–temperature–depth profiles of borehole and lake water; five discrete depth current meter measurements in the lake and images of ice, the lake water–ice interface and lake sediments. Temperature and conductivity data showed the hydrodynamic character of water mixing between the borehole and lake after entry. Models simulating melting of the ~6 m thick basal accreted ice layer imply that debris fall-out through the ~15 m water column to the lake sediments from borehole melting had little effect on the stratigraphy of surficial sediment cores. [ABSTRACT FROM AUTHOR]

Each year, consultants and field scouts working in commercial agriculture undertake a massive, decentralized data collection effort as they monitor insect populations to make real-time pest management decisions. These data, if integrated into a database, offer rich opportunities for applying big data or ecoinformatics methods in agricultural entomology research. However, questions have been raised about whether or not the underlying quality of these data is sufficiently high to be a foundation for robust research. Here I suggest that repeatability analysis can be used to quantify the quality of data collected from commercial field scouting, without requiring any additional data gathering by researchers. In this context, repeatability quantifies the proportion of total variance across all insect density estimates that is explained by differences across populations and is thus a measure of the underlying reliability of observations. Repeatability was moderately high for cotton fields scouted commercially for total Lygus hesperus Knight densities (R = 0.631) and further improved by accounting for observer effects (R = 0.697). Repeatabilities appeared to be somewhat lower than those computed for a comparable, but much smaller, researcher-generated data set. In general, the much larger sizes of ecoinformatics data sets are likely to more than compensate for modest reductions in measurement precision. Tools for evaluating data quality are important for building confidence in the growing applications of ecoinformatics methods. [ABSTRACT FROM AUTHOR]

Although surveys of pest populations documenting evolved insecticide resistance often suggest abundant potential for insecticide control failures, studies documenting the actual occurrence of such failures in commercial agriculture are rare. If farmers currently practice adaptive management, abandoning the use of insecticides once resistance emerges, actual control failures could be rare. Here I use data gathered by independent pest management consultants to describe a case study of the realized efficacy of commercial field applications of insecticides, examining the control of Lygus hesperus Knight on cotton. On average, insecticides reduced target pest populations to 19% of their preapplication densities. Short-term efficacy of insecticides was variable, but only one severe control failure was observed (1 of 50, 2%). The rarity of severe control failures observed in this study is in agreement with the few other studies conducted in commercial settings, but additional research is needed to assess the generality of this result. Although pesticides can cause longer-term problems, including target pest resurgences and secondary pest outbreaks, risk-averse attitudes among farmers coupled with relatively consistent short-term insecticide efficacy may be potent forces propelling farmers toward the use of insecticides. [ABSTRACT FROM AUTHOR]

IL-luminating active tuberculosis disease: Immune responses at the site of Mycobacterium tuberculosis (Mtb) infection can dictate pathogenesis within the infected individual and likelihood of transmission to others. However, the understanding of immunological distinctions between active, latent, and cured tuberculosis disease has been limited to assessment of peripheral blood of patients. Here, Pollara et al. evaluated immune response gene signatures in individuals with active, latent, or cured Mtb infection at the site of a tuberculin skin test, which reflects the immune response at the site of infection. The authors found that active disease, but not latent or cured disease, was associated with exaggerated interleukin-17A (IL-17A) activity and neutrophil recruitment. Thus, IL-17A may represent a therapeutic target for active Mtb infection. Host immune responses at the site of Mycobacterium tuberculosis infection can mediate pathogenesis of tuberculosis (TB) and onward transmission of infection. We hypothesized that pathological immune responses would be enriched at the site of host-pathogen interactions modeled by a standardized tuberculin skin test (TST) challenge in patients with active TB compared to those without disease, and interrogated immune responses by genome-wide transcriptional profiling. We show exaggerated interleukin-17A (IL-17A) and T helper 17 (TH17) responses among 48 individuals with active TB compared to 191 with latent TB infection, associated with increased neutrophil recruitment and matrix metalloproteinase-1 expression, both involved in TB pathogenesis. Curative antimicrobial treatment reversed these observed changes. Increased IL-1β and IL-6 responses to mycobacterial stimulation were evident both in circulating monocytes and in molecular changes at the site of TST in individuals with active TB, supporting a model in which monocyte-derived IL-1β and IL-6 promote TH17 differentiation within tissues. Modulation of these cytokine pathways may provide a rational strategy for host-directed therapy in active TB. [ABSTRACT FROM AUTHOR]

Due to the difficulty of tracking microbial dispersal, it is rarely possible to disentangle the relative importance of dispersal and species sorting for microbial community assembly. Here, we leverage a detailed multilevel network to examine drivers of bacterial community assembly within flowers. We observed flower visitors to 20 focal plant species in a coflowering community in the Sierra Nevada, revealing 289 species of arthropods. We also analyzed bacterial communities on flowers of each species. We found that plant species with similar visitor communities tend to have similar bacterial communities, and visitor identity to be more important than plant relatedness in structuring floral bacterial communities. However, plant species that were hubs of arthropod visitation were not necessarily hubs of floral bacteria, suggesting an important role for species sorting. Across plant species, the composition of flower‐visiting Diptera (flies), bees and non‐bee Hymenoptera best predicted bacterial species composition on flowers. Taken together, our analyses suggest dispersal is important in determining similarity in microbial communities across plant species, but not as important in determining the overall macrostructure (nestedness, modularity) and microstructure (connectedness based on shared interactors) of the floral bacterial network. A multilevel network approach thus allows us to address features of community assembly that cannot be considered when viewing networks as separate entities. [ABSTRACT FROM AUTHOR]

Parental investment by solitary nest‐building wasps and bees is predicted to be plastic, responding to variation in the sex of the offspring, the availability of food used as provisions ('resource limitation'), the female's inventory of mature oocytes ('egg limitation'), and risk imposed by nest parasites.I observed nest provisioning by Ammophila dysmica, a solitary, ground‐nesting wasp that provisions its nest with one or two caterpillar prey to evaluate the hypotheses that provisioning is shaped by caterpillar size, offspring sex, the hunting time required to capture prey, a female's egg load, and penetration of nests by the parasites Argochrysis armilla and Hilarella hilarella.Ammophila dysmica were more likely to add a second provision to the nest when the first prey item was relatively small and when provisioning daughters.Neither the hunting time required to capture the first caterpillar prey nor the female's inventory of oocytes predicted a female's likelihood of adding a second caterpillar to a nest. Variation in oocyte inventory across females was minimal; all females examined had a mature or nearly mature oocyte remaining in the ovaries immediately after laying an egg.Ammophila dysmica were much less likely to add a second caterpillar to nests that were penetrated by parasites during the first provisioning.Although many nest parasites have evolved adaptations to avoid detection by their hosts, oviposition by A. armilla often appears to reveal its presence, eliciting an abrupt truncation of investment by the host in that nest. [ABSTRACT FROM AUTHOR]

Breithaupt et al. (2020, https://doi.org/10.1029/2019JG005349) investigated why rates of organic carbon (OC) burial in coastal wetlands appear to increase over the past ∼120 years. After comparing dating methods and applying biogeochemical analyses, we concluded that neither dating method nor carbon degradation contribute to the observed trend. Rather, we concluded that OC burial has increased in the past century. Parkinson's (2021) Comment disagrees with our conclusion, contending that: (1) use of a density correction to account for soil auto‐compaction is a flawed methodology that artificially shortens a core's length, (2) there is limited evidence for an acceleration in the regional sea‐level rise (SLR) rate, and (3) vertical accretion rates in previous papers by Breithaupt et al. (2014, https://doi.org/10.1002/2014JG002715; 2017, https://doi.org/10.1016/j.margeo.2017.07.002) are lower than the regional mean rate of SLR and are not to be believed as these wetlands should have converted to open water by now. We reject these contentions because: (1) no density correction was applied to the cores in this study, (2) local tide gauge records and analyses in the literature support an increase in SLR rates coinciding with the timeframe of our OC burial records, and (3) Parkinson's comparison of the 100‐yr mean rate of SLR neglects temporal variability and uncertainties in the long‐term sea‐level record, as well as biophysical feedbacks between wetland surface elevation and SLR. Here, we provide detailed responses to Parkinson's contentions and establish the importance of differentiating operational definitions of OC burial and accretion to clarify why an auto‐compaction correction is not applicable for OC burial measurements. Key Points: Organic carbon burial rates are not altered by auto‐compaction and do not include a density correctionIncreasing rates of sea‐level rise are supported by regional data and analyses from the literature [ABSTRACT FROM AUTHOR]

The data and information available at the community-scale are directly linked to the ability to make a resilience-informed decision in natural hazards. This paper develops a systematic approach to quantify the implication of building inventory accuracy on resilience metrics for informed decision-making across engineering, economic and sociological dimensions at the community level. The method of approach consists of: (1) data and information availability, (2) community model development, (3) spatial hazard analysis, (4) physical damage and functionality analysis, and (5) socio-economic impact analysis. This process begins by generating a series of increasingly diminished data quality cases, i.e., increasing the apparent lack of knowledge about the building's structural attributes within a community and developing computational models for each case. Then, damage and functionality analysis are performed to obtain building-level damage estimates, which are then fed into a computable general equilibrium model as well as a population dislocation model to compute a series of physical, economic, and socio-demographics resilience metrics. The estimated metrics are used to quantify the effects of diminishing data availability on physical and socio-economic metrics within the community. The proposed methodology is demonstrated using the illustrative example of the Memphis Metropolitan Statistical Area (MMSA) in Tennessee, USA. [ABSTRACT FROM AUTHOR]

Sweet oranges (Citrus sinensis (L.) Osbeck Sapindales: Rutaceae) dominated commercial citrus production in California until recently when there has been a shift to mandarins, mostly Citrus reticulata (Blanco) mandarins and Citrus clementina (hort. ex Tanaka) clementines. Past analyses of commercial field scouting and harvest data indicated that fork-tailed bush katydids (Scudderia furcata Brunner von Wattenwyl), a major pest in oranges, are present in clementine groves, but that fruit scarring attributed to katydids is rare. Conversely, jagged or web-like scarring attributed to caterpillars was more prevalent than expected. We used two field experiments in four representative cultivars of clementines to test four explanatory hypotheses for this observation: 1) katydids do not feed on clementine fruit, 2) damaged clementine fruit recover, 3) damaged clementine fruit preferentially abscise, and 4) katydid scars on clementine fruit have a different, undocumented morphology, not recognized as katydid damage. We find support for the latter two hypotheses. Katydids fed readily on the clementine fruit of all cultivars tested, chewing irregular holes that developed into jagged or web-like scars of a range of shapes and often led to splitting and abscission of maturing fruit. The katydid scars often more closely resembled chewing caterpillar damage than the round katydid scars in oranges, suggesting that katydid damage is being misclassified in clementines. The resistance documented in some other mandarins was not observed. Katydids are clearly a frugivorous pest causing previously unrecognized scarring in clementines. [ABSTRACT FROM AUTHOR]

Diversifying agricultural landscapes may mitigate biodiversity declines and improve pest management. Yet landscapes are rarely managed to suppress pests, in part because researchers seldom measure key variables related to pest outbreaks and insecticides that drive management decisions. We used a 13‐year government database to analyse landscape effects on European grapevine moth (Lobesia botrana) outbreaks and insecticides across c. 400 Spanish vineyards. At harvest, we found pest outbreaks increased four‐fold in simplified, vineyard‐dominated landscapes compared to complex landscapes in which vineyards are surrounded by semi‐natural habitats. Similarly, insecticide applications doubled in vineyard‐dominated landscapes but declined in vineyards surrounded by shrubland. Importantly, pest population stochasticity would have masked these large effects if numbers of study sites and years were reduced to typical levels in landscape pest‐control studies. Our results suggest increasing landscape complexity may mitigate pest populations and insecticide applications. Habitat conservation represents an economically and environmentally sound approach for achieving sustainable grape production. [ABSTRACT FROM AUTHOR]

Understanding the nature of immunity following mild/asymptomatic infection with SARS-CoV-2 is crucial to controlling the pandemic. We analyzed T cell and neutralizing antibody responses in 136 healthcare workers (HCW) 16-18 weeks after United Kingdom lockdown, 76 of whom had mild/asymptomatic SARS-CoV-2 infection captured by serial sampling. Neutralizing antibodies (nAb) were present in 89% of previously infected HCW. T cell responses tended to be lower following asymptomatic infection than in those reporting case-definition symptoms of COVID-19, while nAb titers were maintained irrespective of symptoms. T cell and antibody responses were sometimes discordant. Eleven percent lacked nAb and had undetectable T cell responses to spike protein but had T cells reactive with other SARS-CoV-2 antigens. Our findings suggest that the majority of individuals with mild or asymptomatic SARS-CoV-2 infection carry nAb complemented by multispecific T cell responses at 16-18 weeks after mild or asymptomatic SARS-CoV-2 infection. [ABSTRACT FROM AUTHOR]

Recent authors have suggested that declines of insect abundance or diversity, documented first for particular insect taxa of high interest (e.g., butterflies, bees), may apply to insect diversity more generally. This has led to an urgent call for analysis of additional longitudinal datasets to examine trends in general insect diversity.Here we present a dataset gathered from 1982 to 2018 by advanced undergraduate students and graduate students enrolled in a taxonomy course that involved collecting as many insect families as possible over a 5‐week period at a high‐elevation protected forested site in the Sierra Nevada, California, USA.The data do not support any consistent gain or loss of family‐level richness between 1982 and 2018 (no linear trend); a non‐linear model suggested a possible small decrease in family‐level richness collected between 1986 and 1990, followed by a gradual increase from 1990 to 2018. Neither weather variables nor collector experience or skill appeared to explain among‐year variation in collected insect diversity.We urge caution in attempting to draw conclusions from single‐site, longitudinal datasets like this one; a definitive answer to the hypothesis of a broad, global decline of insect diversity will require the joint analysis of many datasets like the one we share here. [ABSTRACT FROM AUTHOR]

Enemy‐risk effects, often referred to as non‐consumptive effects (NCEs), are an important feature of predator–prey ecology, but their significance has had little impact on the conceptual underpinning or practice of biological control. We provide an overview of enemy‐risk effects in predator–prey interactions, discuss ways in which risk effects may impact biocontrol programs and suggest avenues for further integration of natural enemy ecology and integrated pest management. Enemy‐risk effects can have important influences on different stages of biological control programs, including natural enemy selection, efficacy testing and quantification of non‐target impacts. Enemy‐risk effects can also shape the interactions of biological control with other pest management practices. Biocontrol systems also provide community ecologists with some of the richest examples of behaviourally mediated trophic cascades and demonstrations of how enemy‐risk effects play out among species with no shared evolutionary history, important topics for invasion biology and conservation. We conclude that the longstanding use of ecological theory by biocontrol practitioners should be expanded to incorporate enemy‐risk effects, and that community ecologists will find many opportunities to study enemy‐risk effects in biocontrol settings. [ABSTRACT FROM AUTHOR]

Pesticides are a ubiquitous component of conventional crop production but come with considerable economic and ecological costs. We tested the hypothesis that variation in pesticide use among crop species is a function of crop economics and the phylogenetic relationship of a crop to native plants because unrelated crops accrue fewer herbivores and pathogens. Comparative analyses of a dataset of 93 Californian crops showed that more valuable crops and crops with close relatives in the native plant flora received greater pesticide use, explaining roughly half of the variance in pesticide use among crops against pathogens and herbivores. Phylogenetic escape from arthropod and pathogen pests results in lower pesticides, suggesting that the introduced status of some crops can be leveraged to reduce pesticides. [ABSTRACT FROM AUTHOR]

Integrated pest management (IPM) guidelines for horticulture are typically established from years of experimental research and experience for a crop species. Ecoinformatics methods can help to quickly adapt these guidelines following major changes in growing practices. Citrus production in California is facing several major challenges, one of which is a shift away from sweet oranges [ Citrus sinensis (L.) Osbeck Sapindales: Rutaceae] toward mandarins (including mostly cultivars of C. reticulata Blanco and C. clementina hort. ex Tanaka). In the absence of IPM guidelines for mandarins, growers are relying on pest information developed from oranges. We mined a database of management records from commercial growers and consultants to determine densities for four arthropod pests: cottony cushion scale (Icerya purchasi Maskell Hemiptera: Monophlebidae), citricola scale (Coccus pseudomagnoliarum Kuwana Hemiptera: Coccidae), European earwig (Forficula auricularia Linnaeus Dermaptera: Forficulidae), citrus red mite (Panonychus citri McGregor Acari: Tetranychidae), and a natural enemy, predatory mites in the genus Euseius (Congdon Acarina: Phytoseiidae). Densities of cottony cushion scale were approximately 10–40 times higher in the two most commonly grown mandarin species than in sweet oranges, suggesting this pest is reaching outbreak levels more often on mandarins. Densities of the other pests and predatory mites did not differ significantly across citrus species. This is a first step toward establishing IPM guidelines for mandarins for these pests; more research is needed to determine how arthropod densities relate to crop performance in mandarins. [ABSTRACT FROM AUTHOR]

Understanding ice sheet evolution through the geologic past can help constrain ice sheet models that predict future ice dynamics. Existing geological records of grounding line retreat in the Ross Sea, Antarctica, have been confined to ice‐free and terrestrial archives, which reflect dynamics from periods of more extensive ice cover. Therefore, our perspective of grounding line retreat since the Last Glacial Maximum remains incomplete. Sediments beneath Ross Ice Shelf and grounded ice offer complementary insight into the southernmost extent of grounding line retreat, yielding a more complete view of ice dynamics during deglaciation. Here we thermochemically separate the youngest organic carbon to estimate ages from sediments extracted near the Whillans Ice Stream grounding line to provide direct evidence of mid‐Holocene (7.5–4.8 kyr B.P.) grounding line retreat in that region. Our study demonstrates the utility of accurately dated, grounding‐line‐proximal sediment deposits for reconstructing past interactions between marine and subglacial environments. Plain Language Summary: Ice sheet grounding lines, where ice loses contact with the underlying bed and transitions to an ice shelf floating on the ocean, are critical areas that govern the stability of marine‐based ice sheets. However, the short period (years to decades) that we have been able to map grounding lines from ground, airborne, and satellite observations compared to the long periods over which ice sheets change (centuries to millenia) limits our knowledge of grounding line stability. We focus our geologic perspective of grounding line retreat in the Ross Sea, a region that has experienced a high degree of change throughout the last glacial‐interglacial cycle. Prior work reconstructing the timeline of ice sheet change in this region is based heavily on ice‐free marine sedimentary records, where dates of the first open marine sedimentation after ice retreat can be estimated. Dating sediments from beneath floating ice shelves and near grounding lines has proven difficult for both logistical and methodological reasons, limiting our understanding of grounding line evolution. We used novel radiocarbon dating methods on sediments collected from beneath the floating Ross Ice Shelf to find that the grounding line retreated inland of the current position during the mid‐Holocene and subsequently readvanced. Key Points: Direct evidence is found for mid‐Holocene grounding line retreat on the Siple Coast, West AntarcticaChronological constraints at Whillans Ice Stream imply western Ross Sea forcing on the southern Siple Coast, in contrast to other Siple Coast ice streamsRamped PyrOx allows for accurate 14C dating of low carbon, grounding‐line‐proximal sediments [ABSTRACT FROM AUTHOR]

Rates of organic carbon (OC) burial in some coastal wetlands appear to be greater in recent years than they were in the past. Possible explanations include ongoing mineralization of older OC or the influence of an unaccounted‐for artifact of the methods used to measure burial rates. Alternatively, the trend may represent real acceleration in OC burial. We quantified OC burial rates of mangrove and coastal freshwater marshes in southwest Florida through a comparison of rates derived from 210Pb, 137Cs, and surface marker horizons. Age/depth profiles of lignin: OC were used to assess whether down‐core remineralization had depleted the OC pool relative to lignin, and lignin phenols were used to quantify the variability of lignin degradation. Over the past 120 years, OC burial rates at seven sites increased by factors ranging from 1.4 to 6.2. We propose that these increases represent net acceleration. Change in relative sea‐level rise is the most likely large‐scale driver of acceleration, and sediment deposition from large storms can contribute to periodic increases. Mangrove sites had higher OC and lignin burial rates than marsh sites, indicating inherent differences in OC burial factors between the two habitat types. The higher OC burial rates in mangrove soils mean that their encroachment into coastal freshwater marshes has the potential to increase burial rates in those locations even more than might be expected from the acceleration trends. Regionally, these findings suggest that burial represents a substantially growing proportion of the coastal wetland carbon budget. Plain Language Summary: Coastal mangroves and marshes use photosynthesis to change carbon dioxide into plant material like leaves, wood, and roots. As these materials die over time, they do not decompose the same way they might in a dry soil environment. Instead, daily ocean tides flood the soil, removing the oxygen and allowing dead plant materials to be buried and preserved for hundreds to thousands of years or more. This "carbon burial" process is a global benefit because it means that carbon dioxide, a greenhouse gas, is stored belowground where it can no longer warm the atmosphere. Mangroves and marshes bury carbon more quickly than most other ecosystems, but little is known about how burial rates change over time. In this study, we quantify how rates of carbon burial have changed in southwest Florida coastal wetlands in the past century. We find that carbon burial is 2.5–4.5 times greater today than it was a century ago in mangroves and 1.9–2.3 times greater in marshes. We propose sea‐level rise as the most likely cause of increased carbon burial. Rising seas provide the means and opportunity for wetlands to bury more carbon, but if sea level rises too quickly, these wetlands may drown. Key Points: Organic carbon burial rates increased by factors of 2.5 to 6.2 for mangroves and 1.4 to 2.4 for coastal freshwater marshes in the past ~120 yearsIncreasing rates represent acceleration rather than a record influenced by an artefact of the dating method or postdepositional degradationAcceleration has increased soil carbon stocks by 5.7–8.0 kg m−2 for mangroves and 4.2–4.5 kg m−2 for coastal freshwater marshes [ABSTRACT FROM AUTHOR]

Recent recession of the Larsen Ice Shelf C has revealed microbial alterations of illite in marine sediments, a process typically thought to occur during low-grade metamorphism. In situ breakdown of illite provides a previously-unobserved pathway for the release of dissolved Fe2+ to porewaters, thus enhancing clay-rich Antarctic sub-ice shelf sediments as an important source of Fe to Fe-limited surface Southern Ocean waters during ice shelf retreat after the Last Glacial Maximum. When sediments are underneath the ice shelf, Fe2+ from microbial reductive dissolution of illite/Fe-oxides may be exported to the water column. However, the initiation of an oxygenated, bioturbated sediment under receding ice shelves may oxidize Fe within surface porewaters, decreasing dissolved Fe2+ export to the ocean. Thus, we identify another ice-sheet feedback intimately tied to iron biogeochemistry during climate transitions. Further constraints on the geographical extent of this process will impact our understanding of iron-carbon feedbacks during major deglaciations. Recent recession of the Larsen Ice Shelf C has revealed that microbial alteration of illite can occur within marine sediments, a process previously thought to only occur abiotically during low-grade metamorphism. Here, the authors show that such microbial alteration of illite could provide a potential source of Fe release to Southern Ocean waters during Holocene glacial cycles. [ABSTRACT FROM AUTHOR]

Plants use a variety of mechanisms to defend against herbivore damage, each with different consequences for agricultural production. Crops relying on tolerance strategies may need different pest management approaches versus those relying on resistance strategies. Previous work suggested that densities of fork-tailed bush katydids (Scudderia furcata Brunner von Wattenwyl [Orthoptera: Tettigoniidae]) that generated substantial scarring on cultivars of sweet oranges (Citrus sinensis , (L.) Osbeck [Sapindales: Rutaceae]) produced only low levels of scarring on cultivars of Citrus reticulata Blanco mandarins. We used field experiments in representative cultivars of these species to test non-mutually exclusive hypotheses regarding the mechanisms underlying this observation: 1) katydids are averse to feeding on mandarin fruits, 2) damaged mandarin fruits preferentially abscise, 3) damaged mandarin fruit tissue recovers during development, and 4) katydid scars on mandarins have a different morphology that may result in misclassification. We found strong support for the first hypothesis, demonstrating that katydids reject opportunities to feed on C. reticulata fruit. Instead of chewing deep holes in the fruit, as was commonly observed for C. sinensis , the katydids only scratched the surface of the C. reticulata fruits. The hypotheses of preferential abscission of damaged fruits and of recovery of damaged tissue were not supported. The low incidence of damage to the mandarins prevented a comprehensive assessment of the scar morphology; however, at harvest, the superficial cuts in C. reticulata were not easily distinguishable from background damage. This indicates that in contrast to C. sinensis , C. reticulata has substantial natural resistance to fork-tailed bush katydids making them a non-pest in this crop. [ABSTRACT FROM AUTHOR]

Several domesticated Citrus species are grown as major commercial crops in California. Despite this, farmers currently use a single set of management practices, originally created for sweet oranges (Citrus sinensis (L.) Osbeck [Sapindales: Rutaceae]), for both sweet oranges and all mandarin species. Mandarins, primarily Citrus reticulata Blanco , Citrus clementina hort. ex Tanaka, and Citrus unshiu Marcovitch, comprise almost 25% of California citrus acreage, and little work has been done to assess host–pest interactions for these species. Citrus thrips (Scirtothripscitri Moulton [Thysanoptera: Thripidae]) are one of the main pests in California citrus and are major targets for early spring, "petal fall" insecticide applications. We used mixed species citrus blocks to test the influence of Citrus species, including C. sinensis, C. reticulata, C. clementina, and C. unshiu , on 1) citrus thrips densities following petal fall; 2) citrus thrips-induced scarring on both the calyx and stylar ends of fruit; and 3) fruit deformation. Citrus sinensis and C. unshiu had relatively high citrus thrips densities and scarring levels, whereas C. reticulata had lower densities of citrus thrips and scarring levels. The age structure of citrus thrips populations also varied across Citrus species. Fruit deformity associated with citrus thrips scarring was found on all Citrus species examined. Scarring on the stylar-end of fruit, a previously largely ignored location of citrus thrips scarring, was found to be common in C. reticulata. It is clear from our work that species-specific management guidelines for citrus thrips are needed in sweet oranges and mandarins. [ABSTRACT FROM AUTHOR]

One of the major challenges facing citrus integrated pest management (IPM) in California is the recent, sharp increase in the acreage of mandarins being planted. The current citrus IPM guidelines have been established from years of experiments and experience in oranges, with no specific guidelines for mandarins. In the absence of research into key arthropod pest effects in mandarins, the assumption that the pest management practices for oranges appropriately transfer for optimal production in mandarins has not been tested. We used a data mining or 'ecoinformatics' approach in which we compiled and analyzed production records collected by growers and pest control advisors to gain an overview of direct pest densities and their relationships with fruit damage for 202 commercial groves, each surveyed for 1–10 yr in the main production region of California. Pest densities were different among four commonly grown species of citrus marketed as mandarins (Citrus reticulata , C. clementina , C. unshiu , and C. tangelo) compared with the standard Citrus sinensis sweet oranges, for fork-tailed bush katydids (Scudderia furcata Brunner von Wattenwyl [Orthoptera: Tettigoniidae]), and citrus thrips (Scirtothrips citri Moulton [Thysanoptera: Thripidae]). Citrus reticulata had notably low levels of fruit damage, suggesting they have natural resistance to direct pests, especially fork-tailed bush katydids. These results suggest that mandarin-specific research and recommendations would improve citrus IPM. More broadly, this is an example of how an ecoinformatics approach can serve as a complement to traditional experimental methods to raise new and unexpected hypotheses that expand our understanding of agricultural systems. [ABSTRACT FROM AUTHOR]

For households of all income levels, and especially for those that are food insecure, food access can be threatened by natural hazards. Extreme natural hazards can disrupt critical infrastructure systems, such as the transportation or electrical power networks, damaging the roads and bridges critical for food supply chains or electrical transmission lines providing electricity for food preservation. Interdependencies among infrastructure systems within the food supply chain make it vulnerable to unanticipated and cascading consequences. Maintaining food security in the aftermath of a natural hazard challenges a community's resilience, recovery, and social well-being. This study introduces a methodology to consider how the interconnectedness among civil infrastructure systems impacts food-security of urban inhabitants. To this end, different infrastructure systems along with their spatial distribution are modeled to evaluate the restoration of food security within a community. Food security metrics, including food availability, accessibility, and affordability, are defined and quantified to provide risk-informed decision support to policymakers in the aftermath of an extreme natural hazard. The methodology proposed herein that considers system interconnectedness and uncertainties in demand and supply can be applied to identify practical policy interventions to hasten recovery of food systems and reduce the adverse impacts of food-insecurity on a community. [ABSTRACT FROM AUTHOR]

Disease and cannibalism are two strongly density-dependent processes that can suppress predator populations. Here we show that California populations of the omnivorous predatory bug Geocoris pallens are subject to infection by a pathogen, as yet unidentified, that elicits elevated expression of cannibalism. Laboratory experiments showed that the pathogen is moderately virulent, causing flattened abdomens, elevated nymphal mortality, delayed development, and reduced body size of adult females. Infection furthermore increases the expression of cannibalism. Field populations of Geocoris spp. declined strongly in association with sharp increases in the expression of egg cannibalism by adult G. pallens. Increased cannibalism was accompanied by a strongly bimodal distribution of cannibalism expression, with some females (putatively uninfected) expressing little cannibalism and others (putatively infected) consuming most or all of the eggs present. Highly cannibalistic females did not increase their consumption of Ephestia cautella moth eggs, suggesting that the high cannibalism phenotype reflected a specific loss of restraint against eating conspecifics. Highly cannibalistic females also often exhibited reduced egg laying, consistent with a virulent pathogen; less frequently, more cannibalistic females exhibited elevated egg laying, suggesting that cannibalism might also facilitate recycling of nutrients in eggs. Elevated cannibalism was not correlated with reduced prey availability or elevated field densities of G. pallens. Geocoris pallens population crashes appear to reflect the combined consequences of direct virulence—adverse pathogen effects on the infected host's physiology—and indirect virulence—mortality of both infected and uninfected individuals due to elevated cannibalism expression by infected individuals. [ABSTRACT FROM AUTHOR]

Hydrocarbons released during the Deepwater Horizon (DWH) oil spill weathered due to exposure to oxygen, light, and microbes. During weathering, the hydrocarbons’ reactivity and lability was altered, but it remained identifiable as “petrocarbon” due to its retention of the distinctive isotope signatures (14C and 13C) of petroleum. Relative to the initial estimates of the quantity of oil-residue deposited in Gulf sediments based on 2010–2011 data, the overall coverage and quantity of the fossil carbon on the seafloor has been attenuated. To analyze recovery of oil contaminated deep-sea sediments in the northern Gulf of Mexico we tracked the carbon isotopic composition (13C and 14C, radiocarbon) of bulk sedimentary organic carbon through time at 4 sites. Using ramped pyrolysis/oxidation, we determined the thermochemical stability of sediment organic matter at 5 sites, two of these in time series. There were clear differences between crude oil (which decomposed at a lower temperature during ramped oxidation), natural hydrocarbon seep sediment (decomposing at a higher temperature; Δ14C = -912‰) and our control site (decomposing at a moderate temperature; Δ14C = -189‰), in both the stability (ability to withstand ramped temperatures in oxic conditions) and carbon isotope signatures. We observed recovery toward our control site bulk Δ14C composition at sites further from the wellhead in ~4 years, whereas sites in closer proximity had longer recovery times. The thermographs also indicated temporal changes in the composition of contaminated sediment, with shifts towards higher temperature CO2 evolution over time at a site near the wellhead, and loss of higher temperature CO2 peaks at a more distant site. [ABSTRACT FROM AUTHOR]