INVASIVE ASIAN EARTHWORMS NEGATIVELY IMPACT WOODLAND SALAMANDERS: COMPETITIVE EXCLUSION, FORAGING INTERFERENCE, AND HABITAT DEGRADATION REDUCE SALAMANDER DENSITY

Asian earthworms (Amynthas spp.) are invading North American forests and consuming the vital detrital layer that forest floor biota (including the Eastern Red-backed Salamander, Plethodon cinereus) rely on for protection, food, and habitat. Salamander population decline has been associated with European earthworm-mediated leaf litter loss, but there have been few studies on the interactions between Amynthas spp. and P. cinereus. Since the large, active Amynthas spp. earthworms spatially overlap with salamanders beneath natural cover objects and in detritus, they may compound the negative consequences of resource degradation by physically disturbing important salamander activities (foraging, mating, and egg brooding). I predicted that Amynthas spp. would exclude salamanders from high quality microhabitat, reduce foraging efficiency, and negatively affect salamander fitness. In laboratory trials, salamanders used lower quality microhabitat and consumed fewer flies in the presence of earthworms than when alone. In a natural field experiment conducted on salamander populations from “non-invaded” and “Amynthas-invaded” sites in Ohio, salamanders and Amynthas spp. shared cover objects ~60% less than expected. However, there was no effect of Amynthas spp. invasion on salamander body condition. Amynthas spp. density was negatively associated with juvenile and male salamander density, but had no relationship with female salamander density. Juvenile and non-resident male salamanders do not hold stable territories, which results in reduced access to prey and a higher risk of desiccation. 2 Degraded leaf litter layers in Amynthas-invaded forests may uniquely challenge juvenile and male salamanders, exposing them to increased risk of desiccation, predation, and starvation as they search for suitable, unoccupied surface microhabitat. If habitat degradation and physical exclusion of salamanders from cover objects reduce juvenile and male salamander performance, then recruitment and ultimately salamander abundance may decline following Amynthas spp. invasion

Total Organic Carbon and the Contribution From Speciated Organics in Cloud Water: Airborne Data Analysis From the CAMP2Ex Field Campaign

This work focuses on total organic carbon (TOC) and contributing species in cloud water over Southeast Asia using a rare airborne dataset collected during NASA’s Cloud, Aerosol and Monsoon Processes Philippines Experiment (CAMP2Ex), in which a wide variety of maritime clouds were studied, including cumulus congestus, altocumulus, altostratus, and cumulus. Knowledge of TOC masses and their contributing species is needed for improved modeling of cloud processing of organics and to understand how aerosols and gases impact and are impacted by clouds. This work relies on 159 samples collected with an axial cyclone cloudwater collector at altitudes of 0.2–6.8 km that had sufficient volume for both TOC and speciated organic composition analysis. Species included monocarboxylic acids (glycolate, acetate, formate, and pyruvate), dicarboxylic acids (glutarate, adipate, succinate, maleate, and oxalate), methanesulfonic acid (MSA), and dimethylamine (DMA). TOC values range between 0.018 and 13.66 ppm C with a mean of 0.902 ppm C. The highest TOC values are observed below 2 km with a general reduction aloft. An exception is samples impacted by biomass burning for which TOC remains enhanced at altitudes as high as 6.5 km (7.048 ppm C). Estimated total organic matter derived from TOC contributes a mean of 30.7 % to total measured mass (inorganics + organics). Speciated organics contribute (on a carbon mass basis) an average of 30.0 % to TOC in the study region and account for an average of 10.3 % to total measured mass. The order of the average contribution of species to TOC, in decreasing contribution of carbon mass, is as follows (±1 standard deviation): acetate (14.7 ± 20.5 %), formate (5.4 ± 9.3 %), oxalate (2.8 ± 4.3 %), DMA (1.7 ± 6.3 %), succinate (1.6 ± 2.4 %), pyruvate (1.3 ± 4.5 %), glycolate (1.3 ± 3.7 %), adipate (1.0 ± 3.6 %), MSA (0.1 ± 0.1 %), glutarate (0.1 ± 0.2 %), and maleate (\u3c 0.1 ± 0.1 %). Approximately 70 % of TOC remains unaccounted for, highlighting the complex nature of organics in the study region; in samples collected in biomass burning plumes, up to 95.6 % of TOC mass is unaccounted for based on the species detected. Consistent with other regions, monocarboxylic acids dominate the speciated organic mass (∼ 75 %) and are about 4 times more abundant than dicarboxylic acids. Samples are categorized into four cases based on backtrajectory history, revealing source-independent similarity between the bulk contributions of monocarboxylic and dicarboxylic acids to TOC (16.03 %–23.66 % and 3.70 %–8.75 %, respectively). Furthermore, acetate, formate, succinate, glutarate, pyruvate, oxalate, and MSA are especially enhanced during biomass burning periods, which is attributed to peat emissions transported from Sumatra and Borneo. Lastly, dust (Ca2+) and sea salt (Na+/Cl−) tracers exhibit strong correlations with speciated organics, supporting how coarse aerosol surfaces interact with these water-soluble organics

Time-Efficient Inspiratory Muscle Strength Training Lowers Blood Pressure and Improves Endothelial Function, NO Bioavailability, and Oxidative Stress in Midlife/Older Adults With Above-Normal Blood Pressure

Background High‐resistance inspiratory muscle strength training (IMST) is a novel, time‐efficient physical training modality. &nbsp; Methods and Results We performed a double‐blind, randomized, sham‐controlled trial to investigate whether 6&nbsp;weeks of IMST (30&nbsp;breaths/day, 6&nbsp;days/week) improves blood pressure, endothelial function, and arterial stiffness in midlife/older adults (aged 50&ndash;79&nbsp;years) with systolic blood pressure &ge;120&nbsp;mm&nbsp;Hg, while also investigating potential mechanisms and long‐lasting effects. Thirty‐six participants completed high‐resistance IMST (75% maximal inspiratory pressure, n=18) or low‐resistance sham training (15% maximal inspiratory pressure, n=18). IMST was safe, well tolerated, and had excellent adherence (&asymp;95% of training sessions completed). Casual systolic blood pressure decreased from 135&plusmn;2&nbsp;mm&nbsp;Hg to 126&plusmn;3&nbsp;mm&nbsp;Hg (P&lt;0.01) with IMST, which was &asymp;75% sustained 6&nbsp;weeks after IMST (P&lt;0.01), whereas IMST modestly decreased casual diastolic blood pressure (79&plusmn;2&nbsp;mm&nbsp;Hg to 77&plusmn;2&nbsp;mm&nbsp;Hg, P=0.03); blood pressure was unaffected by sham training (all P&gt;0.05). Twenty‐four hour systolic blood pressure was lower after IMST versus sham training (P=0.01). Brachial artery flow‐mediated dilation improved &asymp;45% with IMST (P&lt;0.01) but was unchanged with sham training (P=0.73). Human umbilical vein endothelial cells cultured with subject serum sampled after versus before IMST exhibited increased NO bioavailability, greater endothelial NO synthase activation, and lower reactive oxygen species bioactivity (P&lt;0.05). IMST decreased C‐reactive protein (P=0.05) and altered select circulating metabolites (targeted plasma metabolomics) associated with cardiovascular function. Neither IMST nor sham training influenced arterial stiffness (P&gt;0.05). &nbsp; Conclusions High‐resistance IMST is a safe, highly adherable lifestyle intervention for improving blood pressure and endothelial function in midlife/older adults with above‐normal initial systolic blood pressure. &nbsp; Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT03266510. &nbsp;</p

Genetic Testing: Pass or Fail?

Testing genetic testing companies for substantiated evidence behind testingSummer 201

Data from: Invasive Asian earthworms negatively impact keystone terrestrial salamanders

Asian pheretimoid earthworms (e.g. Amynthas and Metaphire spp.) are invading North American forests and consuming the vital detrital layer that forest floor biota [including the keystone species Plethodon cinereus (Eastern Red-backed Salamander)], rely on for protection, food, and habitat. Plethodon cinereus population declines have been associated with leaf litter loss following the invasion of several exotic earthworm species, but there have been few studies on the specific interactions between pheretimoid earthworms and P. cinereus. Since some species of large and active pheretimoids spatially overlap with salamanders beneath natural cover objects and in detritus, they may distinctively compound the negative consequences of earthworm-mediated resource degradation by physically disturbing important salamander activities (foraging, mating, and egg brooding). We predicted that earthworms would exclude salamanders from high quality microhabitat, reduce foraging efficiency, and negatively affect salamander fitness. In laboratory trials, salamanders used lower quality microhabitat and consumed fewer flies in the presence of earthworms. In a natural field experiment, conducted on salamander populations from “non-invaded” and “pheretimoid invaded” sites in Ohio, salamanders and earthworms shared cover objects ~60% less than expected. Earthworm abundance was negatively associated with juvenile and male salamander abundance, but had no relationship with female salamander abundance. There was no effect of pheretimoid invasion on salamander body condition. Juvenile and non-resident male salamanders do not hold stable territories centered beneath cover objects such as rocks or logs, which results in reduced access to prey, greater risk of desiccation, and dispersal pressure. Habitat degradation and physical exclusion of salamanders from cover objects may hinder juvenile and male salamander performance, ultimately reducing recruitment and salamander abundance following Asian earthworm invasion

Invasive Asian Earthworms Negatively Impact Keystone Terrestrial Salamanders

<div><p>Asian pheretimoid earthworms (e.g. <i>Amyntha</i>s and <i>Metaphire</i> spp.) are invading North American forests and consuming the vital detrital layer that forest floor biota [including the keystone species <i>Plethodon cinereus</i> (Eastern Red-backed Salamander)], rely on for protection, food, and habitat. <i>Plethodon cinereus</i> population declines have been associated with leaf litter loss following the invasion of several exotic earthworm species, but there have been few studies on the specific interactions between pheretimoid earthworms and <i>P</i>. <i>cinereus</i>. Since some species of large and active pheretimoids spatially overlap with salamanders beneath natural cover objects and in detritus, they may distinctively compound the negative consequences of earthworm-mediated resource degradation by physically disturbing important salamander activities (foraging, mating, and egg brooding). We predicted that earthworms would exclude salamanders from high quality microhabitat, reduce foraging efficiency, and negatively affect salamander fitness. In laboratory trials, salamanders used lower quality microhabitat and consumed fewer flies in the presence of earthworms. In a natural field experiment, conducted on salamander populations from “non-invaded” and “pheretimoid invaded” sites in Ohio, salamanders and earthworms shared cover objects ~60% less than expected. Earthworm abundance was negatively associated with juvenile and male salamander abundance, but had no relationship with female salamander abundance. There was no effect of pheretimoid invasion on salamander body condition. Juvenile and non-resident male salamanders do not hold stable territories centered beneath cover objects such as rocks or logs, which results in reduced access to prey, greater risk of desiccation, and dispersal pressure. Habitat degradation and physical exclusion of salamanders from cover objects may hinder juvenile and male salamander performance, ultimately reducing recruitment and salamander abundance following Asian earthworm invasion.</p></div

Equal probability plot for high quality (HQ) microhabitat use when salamanders (<i>Plethodon cinereus</i>) were alone or paired with pheretimoid earthworms.

<p>The diagonal line indicates no difference in a salamander’s HQ zone use when they were alone vs. paired with an earthworm. Points above the line represent salamanders that used the HQ zone more often when alone, while points below the line represent salamanders that used the HQ zone more often when paired with an earthworm.</p

Amphibian Dispersal Traits Not Impacted by Triclopyr Exposure during the Juvenile Stage

Exposure to agrochemicals can have lethal and sublethal effects on amphibians. Most toxicology studies only examine exposure during the aquatic larval stage. Survival of the juvenile stage is the most important for population persistence and it is critical to understand the potential impacts of exposure during this life stage. We investigated how short-term exposure to triclopyr, an herbicide commonly used in forestry management, might impact several juvenile traits. To determine if juveniles perceived exposure as an environmental stressor, we measured their release of corticosterone. We also examined dispersal traits by measuring foraging and hopping behavior. We found no evidence that exposure negatively impacted these traits or was a stressor. Our results provide a preliminary assessment of the potential impact of triclopyr on juvenile amphibians, but we recommend additional research on the effects of agrochemicals on juvenile amphibians

A comparison of large pheretimoid earthworm population characteristics [33, 34] at the soil surface and <i>Plethodon cinereus</i> microhabitat occupancy [35] throughout the year in Ohio, USA.

<p>A comparison of large pheretimoid earthworm population characteristics [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0151591#pone.0151591.ref033" target="_blank">33</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0151591#pone.0151591.ref034" target="_blank">34</a>] at the soil surface and <i>Plethodon cinereus</i> microhabitat occupancy [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0151591#pone.0151591.ref035" target="_blank">35</a>] throughout the year in Ohio, USA.</p

The relationship between pheretimoid earthworm and <i>P</i>. <i>cinereus</i> as measured by earthworm abundance and LL score.

<p>Juveniles were significantly associated with earthworm abundance (A) and LL score (D). There was a negative relationship between earthworm and male salamander abundance (B) but no relationship between male salamanders and LL score (E). Female salamanders were neither associated with worm abundance (C) or LL score (F). Asterisks indicate statistically significant results.</p