Laboratory evaluation of stable isotope labeling of Culicoides (Diptera: Ceratopogonidae) for adult dispersal studies.

BackgroundStable isotope labeling is a promising method for use in insect mark-capture and dispersal studies. Culicoides biting midges, which transmit several important animal pathogens, including bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV), are small flies that develop in various semi-aquatic habitats. Previous Culicoides dispersal studies have suffered from the limitations of other labeling techniques, and an inability to definitively connect collected adult midges to specific immature development sites.ResultsAdult C. sonorensis were successfully labeled with 13C and 15N stable isotopes as larvae developing in a semi-aquatic mud substrate in the laboratory. High and low-dose isotope treatments for both elements significantly enriched midges above the background isotope levels of unenriched controls. Enrichment had no effect on C. sonorensis survival, though a slight (~ 5 day) delay in emergence was observed, and there was no significant effect of pool size on 13C or 15N enrichment levels.ConclusionsStable isotope labeling is life-long, and does not interfere with natural insect behaviors. Stable isotope enrichment using 13C or 15N shows promise for Culicoides dispersal studies in the field. This method can be used to identify adult dispersal from larval source habitat where a midge developed. It may be possible to detect a single enriched midge in a pool of unenriched individuals, though further testing is needed to confirm the sensitivity of this method

Reproducibility of Ba/Ca variations recorded by northeast Pacific bamboo corals

Author Posting. © American Geophysical Union, 2017. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Paleoceanography 32 (2017): 966–979, doi:10.1002/2017PA003178.Trace elemental ratios preserved in the calcitic skeleton of bamboo corals have been shown to serve as archives of past ocean conditions. The concentration of dissolved barium (BaSW), a bioactive nutrientlike element, is linked to biogeochemical processes such as the cycling and export of nutrients. Recent work has calibrated bamboo coral Ba/Ca, a new BaSW proxy, using corals spanning the oxygen minimum zone beneath the California Current System. However, it was previously unclear whether Ba/Cacoral records were internally reproducible. Here we investigate the accuracy of using laser ablation inductively coupled plasma mass spectrometry for Ba/Cacoral analyses and test the internal reproducibility of Ba/Ca among replicate radial transects in the calcite of nine bamboo corals collected from the Gulf of Alaska (643–720 m) and the California margin (870–2054 m). Data from replicate Ba/Ca transects were aligned using visible growth bands to account for nonconcentric growth; smoothed data were reproducible within ~4% for eight corals (n = 3 radii/coral). This intracoral reproducibility further validates using bamboo coral Ba/Ca for BaSW reconstructions. Sections of the Ba/Ca records that were potentially influenced by noncarbonate bound Ba phases occurred in regions where elevated Mg/Ca or Pb/Ca and coincided with anomalous regions on photomicrographs. After removing these regions of the records, increased Ba/Cacoral variability was evident in corals between ~800 and 1500 m. These findings support additional proxy validation to understand BaSW variability on interannual timescales, which could lead to new insights into deep sea biogeochemistry over the past several centuries.NSF Grant Number: OCE-1420984; NOAA/OE Grant Number: NA16RP2637; MIT-WHOI Joint Program; American Geophysical Union Travel Grant; UC Davis President's Undergraduate Fellowship; Bowdoin College Gibbons Summer Research Fellowship2018-03-1

Corrigendum to “Insights into methane dynamics from analysis of authigenic carbonates and chemosynthetic mussels at newly-discovered Atlantic Margin seeps” [Earth Planet. Sci. Lett. 449 (2016) 332–344]

This paper is not subject to U.S. copyright. The definitive version was published in Earth and Planetary Science Letters 475 (2017): 268, doi:10.1016/j.epsl.2017.07.037

Heterotrophy of oceanic particulate organic matter elevates net ecosystem calcification

Author Posting. © American Geophysical Union, 2019. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 46(16), (2019): 9851-9860, doi:10.1029/2019GL083726.Coral reef calcification is expected to decline due to climate change stressors such as ocean acidification and warming. Projections of future coral reef health are based on our understanding of the environmental drivers that affect calcification and dissolution. One such driver that may impact coral reef health is heterotrophy of oceanic‐sourced particulate organic matter, but its link to calcification has not been directly investigated in the field. In this study, we estimated net ecosystem calcification and oceanic particulate organic carbon (POCoc) uptake across the Kāne'ohe Bay barrier reef in Hawai'i. We show that higher rates of POCoc uptake correspond to greater net ecosystem calcification rates, even under low aragonite saturation states (Ωar). Hence, reductions in offshore productivity may negatively impact coral reefs by decreasing the food supply required to sustain calcification. Alternatively, coral reefs that receive ample inputs of POCoc may maintain higher calcification rates, despite a global decline in Ωar.Data needed for calculations are available in the supporting information. Additional data can be provided upon request directly from the corresponding author or accessed by links provided in the supporting information. The authors declare no competing financial interests. We thank Texas Sea Grant for providing partial funding for this project to A. Kealoha through the Grants‐In‐Aid of Graduate Research Program. We also thank the NOAA Nancy Foster Scholarship for PhD program funding to A. Kealoha and Texas A&M University for funds awarded to Shamberger that supported this work. This research was also supported by funding from National Science Foundation Grant OCE‐1538628 to Rappé. The Hawaii Institute of Marine Biology (particularly the Rappé Lab and Jason Jones), NOAA's Coral Reef Ecosystem Program, Connie Previti, Serena Smith, and Chris Maupin were instrumental in sample collection and data analysis.2020-02-2

Hacer memoria de la vida religiosa

Los autores intentan hacer una síntesis del camino que ha recorrido la vida religiosa en América Latina destacando la complejidad y la riqueza que supone la vocación a la vida religiosa expresado por los autores de esta manera: “el martirologio de América Latina está lleno en estos últimos tiempos, de religiosos y religiosas que testimoniaron con su vida lo que creían y predicaban". En este artículo se analiza el origen misionero de la vida religiosa antes del Concilio Vaticano II, las transformaciones que ha tenido la vida religiosa después del concilio con la relectura del mismo en Medellín, Puebla, también se analizan los grandes cambios que han surgido al final del S. XX, así como las implicaciones para los religiosos(as) y lo que sucede en Santo Domingo, Conferencia en la que se reafirma la opción por los pobres, se plantea el reto de la inculturación, se tratan temas como la tierra, los laicos, los jóvenes y la mujer en la encrucijada del paso de la modernidad a la postmodernidad. Se señala en el primer párrafo de este escrito: “No resulta fácil hacer una apretada síntesis del camino recorrido por la vida religiosa en América Latina. La vida es mucha más rica que cualquier expresión de ella. Y ciertamente la vida religiosa en América Latina ha escrito páginas bellísimas, de fidelidad y de compromiso con los más desheredados de la tierra, de comunión y participación en las grandes luchas por la promoción y la dignidad de todo hombre, sobre todo de los más empobrecidos y marginados, esforzándose hasta el sacrificio de la vida por desterrar la injusticia y la pobreza que han marcado duramente a esta tierra generosa. Han sido páginas, cargadas de creatividad y coraje, refrendadas, a veces, con el testimonio irrefutable de la sangre. Ya desde el comienzo fueron «intrépidos luchadores por la justicia, evangelizadores de la paz» y lo han continuado siendo hasta nuestros días: el martirologio de América Latina está lleno en estos últimos tiempos, de religiosos y religiosas que testimoniaron con su vida lo qué creían y predicaban”

Bottom-contact fisheries disturbance and signs of recovery of precious corals in the Northwestern Hawaiian Islands and Emperor Seamount Chain

Deep-sea precious corals in the octocoral family Coralliidae are among the dominant benthic megafauna at depths of 300–600 m on seamounts of the Northwestern Hawaiian Islands and lower Emperor Seamount Chain. Pleurocorallium secundum and Hemicorallium laauense were once abundant enough on these seamounts to support a targeted coral fishery in the 1960s and 1970s. Significant trawl finfish fisheries were also occurring in the same time frame on the same seamounts. Because they had high enough abundance to support a targeted fishery for two decades, these two coralliid species must have been a key component of the baseline community on these seamounts. Therefore, they provide an ideal indicator species for testing effects of large-scale disturbance and potential for recovery in deep-sea coral and seamount communities. Using AUVs and submersibles, we explored seamounts outside the US EEZ that are still actively fished by trawl, seamounts within the US EEZ that were historically trawled but have been protected since the establishment of the EEZ, and seamounts that have never been trawled, to determine population distributions and colony sizes for the targeted coral species. P. secundum had only one individual on actively trawled seamounts and occurred in low abundance on most Recovering seamounts. H. laauense was present in a few areas in Recovering and Still Trawled seamounts. Colony size distributions for H. laauense showed a smaller median size on Recovering and Still Trawled seamounts compared to the Never Trawled sites. P. secundum had a slightly smaller median colony size on the Recovering Seamounts than on the Never Trawled seamounts. These results indicate a reduction in abundance for both species in disturbed areas with some unexpected potential for recovery on protected seamounts. Recovery was uneven among sites and species with SE Hancock and Koko showing the largest populations of H. laauense among the Recovering and Still Trawled seamounts, respectively. P. secundum showed much less recovery, with its largest population on Bank 11 in the Recovering seamounts. Kammu, one of the primary seamounts of the coral fishery, had only a single coralliid observed. The other primary target, Yuryaku, had a small number of coralliids in a steeply sloped area. These two Still Trawled seamounts do not appear to be able to recover under the current levels of fishing pressure

Age determination of submillennial scale climate events of ODP Hole 146-893A

Evidence is presented from ODP Hole 893A, Santa Barbara Basin for possible synchroneity between Greenland and California Margin submillennial climate change records during Termination 1 and the Last Glacial Maximum (LGM). Planktonic foraminiferal isotope and faunal records are compared to the GISP2 d18O records (Greenland) for the interval between 30 and 10 ka using a new chronology, based on 38 planktonic 14C dates. Apparent synchronous climatic events include: Interstadial (IS) events 2, 3 and 4; A broad warming trend between 21 and 19 ka and a broad cooling trend between 19 and 17 ka; Bølling and Ållerød warm episodes separated by the cooler Older Dryas event; Younger Dryas cool episode; and the Preboreal. The resulting tight correlation supports an intimate teleconnection between Santa Barbara Basin surface waters and Greenland air temperatures. Differences between Greenland and Santa Barbara Basin suggest that some regional variations were superimposed on the global pattern of climate change (e.g. the Pre-Bølling Warming)