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Sample records for earthworm avoidance test

  1. THE POTENTIAL OF AN EARTHWORM AVOIDANCE TEST FOR EVALUATION OF HAZARDOUS WASTE SITES

    EPA Science Inventory

    An earthworm avoidance test has potential advantages for use in evaluation of hazardous wastes sites. Because organisms often exhibit behavioral responses at lower levels of stress than those that acute toxicity tests are able to detect, avoidance tests could provide increased se...

  2. The potential of an earthworm avoidance test for evaluation of hazardous waste sites

    SciTech Connect

    Yeardley, R.B. Jr.; Gast, L.C.; Lazorchak, J.M.

    1996-09-01

    An earthworm avoidance test has potential advantages for use in evaluation of hazardous wastes sites. Because organisms often exhibit behavioral responses at lower levels of stress than those that acute toxicity tests are able to detect, avoidance tests could provide increased sensitivity to hazardous chemicals. Avoidance is an ecologically relevant endpoint that neither acute nor sublethal tests measure. Avoidance can potentially indicate sublethal stress in a short period of time, testing is easily done in a soil matrix, and an avoidance test has the potential for specialized applications for soil testing. Dual-control test data established that, in absence of a toxicant, worms did not congregate, but instead distributed themselves fairly randomly with respect to the two sides of the test chambers, that is, they did not display behavior that might be mistaken for avoidance. In tests with artificial soil spiked with reference toxicants and hazardous site soils, worms avoided soils containing various toxic chemicals. Avoidance behavior proved in most cases be a more sensitive indicator of chemical contamination than acute tests. Determination of avoidance was possible in 1 to 2 d, much less than the current duration of acute and sublethal earthworm tests.

  3. Avoidance tests with Collembola and earthworms as early screening tools for site-specific assessment of polluted soils.

    PubMed

    da Luz, Tiago Natal; Ribeiro, Rui; Sousa, José Paulo

    2004-09-01

    Avoidance tests with earthworms and collembolans were conducted to demonstrate their feasibility as early screening tools for assessing the toxic potential of metal-polluted soils. Four different soils, with different degrees of metal contamination, were obtained from an abandoned mining area. All possible paired combinations were assessed for an avoidance response by the organisms. Data revealed that both species were able to avoid the most contaminated soils at the center of the ore extraction and treatment areas compared to those collected further away from the mine. However, earthworms and springtails differed in sensitivity to metals, especially when testing the two most polluted soils that had different contamination profiles. Earthworms exhibited a more consistent, less variable response than springtails. Overall results showed that avoidance tests with collembolans and earthworms have the potential to be used as screening tools in ecological risk assessment schemes for contaminated land, to trigger other tests in case of concern. However, further method development is needed to reduce variability in the data, particularly in the Collembola assays, and to gain knowledge about the possible effects of soil properties on the outcome of the tests. PMID:15378996

  4. Survival, Pb-uptake and behaviour of three species of earthworm in Pb treated soils determined using an OECD-style toxicity test and a soil avoidance test.

    PubMed

    Langdon, Caroline J; Hodson, Mark E; Arnold, Rebecca E; Black, Stuart

    2005-11-01

    Mature (clitellate) Eisenia andrei Bouché (ultra epigeic), Lumbricus rubellus Hoffmeister (epigeic), and Aporrectodea caliginosa (Savigny) (endogeic) earthworms were placed in soils treated with Pb(NO(3))(2) to have concentrations in the range 1,000 to 10,000 mg Pb kg(-1). After 28 days LC50(-95%confidence limit)(+95%confidence limit) values were E. andrei 5824(-361)(+898) mg Pb kg(-1), L. rubellus 2867(-193)(+145) mg Pb kg(-1) and A. caliginosa2747(-304)(+239) mg Pb kg(-1) and EC50s for weight change were E. andrei2841(-68)(+150) mg Pb kg(-1), L. rubellus1303(-201)(+240) mg Pb kg(-1) and A. caliginosa1208(-206)(+212) mg Pb kg(-1). At any given soil Pb concentration, Pb tissue concentrations after 28 days were the same for all three earthworm species. In a soil avoidance test there was no difference between the behaviour of the different species. The lower sensitivity to Pb exhibited by E. andrei is most likely due to physiological adaptations associated with the modes of life of the earthworms, and could have serious implications for the use of this earthworm as the species of choice in standard toxicological testing. PMID:15951078

  5. Earthworm (Eisenia andrei) Avoidance of Soils Treated with Cypermethrin

    PubMed Central

    de Sousa, Ana Paula A.; de Andréa, Mara M.

    2011-01-01

    The pyrethroid insecticide cypermethrin is used for agricultural and public health campaigns. Its residues may contaminate soils and the beneficial soil organisms, like the earthworms, that may ingest the contaminated soil particles. Due to its ecological relevance, earthworms Eisenia andrei/fetida have been used in different ecotoxicological tests. The avoidance of soils treated with cypermethrin by compost worms Eisenia andrei was studied here as a bioindicator of the influence of treatment dosage and the pesticide formulation in three different agricultural soils indicated by the Brazilian environmental authorities for ecotoxicological tests. This earthworms’ behavior was studied here as a first attempt to propose the test for regulation purposes. The two-compartment test systems, where the earthworms were placed for a two-day exposure period, contained samples of untreated soil alone or together with soil treated with technical grade or wettable powder formulation of cypermethrin. After 48 h, there was no mortality, but the avoidance was clear because all earthworms were found in the untreated section of each type of soil (p < 0.05). No differences were found by the Fisher’s exact test (p ≤ 1.000) for each soil and treatment, demonstrating that the different soil characteristics, the cypermethrin concentrations and formulation, as well as the smaller amounts of soil and earthworms did not influence the avoidance behavior of the earthworms to cypermethrin. The number and range of treatments used in this study do not allow a detailed recommendation of the conditions applied here, but to the best of our knowledge, this is the first reported attempt to identify the avoidance of pesticide treated tropical soils by earthworms. PMID:22247652

  6. Biochar aging reduces earthworm avoidance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biochar, a black carbon substance produced by the pyrolysis of organic feedstocks, has been used in many soil improvement strategies ranging from nutrient addition to sequestration of C. Simple toxicity studies and laboratory preference/avoidance assays are recommended but results rarely reported. ...

  7. Avoidance behaviour response and esterase inhibition in the earthworm, Lumbricus terrestris, after exposure to chlorpyrifos.

    PubMed

    Martínez Morcillo, S; Yela, J L; Capowiez, Y; Mazzia, C; Rault, M; Sanchez-Hernandez, Juan C

    2013-05-01

    The avoidance response of earthworms to polluted soils has been standardised using a simple and low-cost test, which facilitates soil toxicity screening. In this study, the avoidance response of Lumbricus terrestris was quantified in chlorpyrifos-spiked soils, depending on the pesticide concentration and exposure duration. The inhibition of acetylcholinesterase (AChE) and carboxylesterase (CbE) activities was also determined as indirect measures of pesticide bioavailability. The effects of different chlorpyrifos concentrations were examined in a standardised test (two-chamber system) with 0.6, 3 and 15 mg/kg chlorpyrifos. A modification of the test involved a pre-exposure step (24, 48 or 72 h) in soils spiked with 15 mg/kg. In both protocols, earthworms were unable to avoid the contaminated soils. However, the esterase activities showed that all earthworms were exposed to chlorpyrifos. Acetylcholinesterase activity did not change in earthworms in the standardised behavioural test (0.58 ± 0.20 U/mg protein, mean ± SD; n = 72), whereas the CbE activity was significantly inhibited (62-87 % inhibition) in earthworms exposed to 3 and 15 mg/kg. In the modified test, earthworms had greatly inhibited AChE activity (0.088 ± 0.034 U/mg protein, n = 72), which was supported by reactivation of the inhibited enzyme activity in the presence of pralidoxime (2-PAM). Similarly, the CbE activity was significantly inhibited in earthworms with all treatments. This study suggests that the avoidance behaviour test for organophosphorus-contaminated soils could be supported by specific biomarkers to facilitate a better understanding of pesticide exposure and toxicity during this test. PMID:23435687

  8. Assessment of avoidance behaviour by earthworms (Lumbricus rubellus and Octolasion cyaneum) in linear pollution gradients.

    PubMed

    Lowe, Christopher N; Butt, Kevin R; Cheynier, Kevin Yves-Marie

    2016-02-01

    Avoidance behaviour by earthworms is recognised as a valuable endpoint in soil quality assessment and has resulted in the development of a standardised test (ISO 17512-1, 2008) providing epigeic earthworms with a choice between test and control soils. This study sought to develop and evaluate an avoidance test utilising soil-dwelling earthworms in linear pollution gradients with Visible Implant Elastomer (VIE) tags used to identify individual organisms. Sequential experiments were established in laboratory-based mesocosms (0.6m×0.13m×0.1m) that determined the relative sensitivities (in terms of associated avoidance behaviour) of Octolasion cyaneum and Lumbricus rubellus at varying levels of polluted soil and also assessed the influence of introduction point on recorded movement within gradients. In an initial gradient (0%, 25%, 50%, 75%, 100% polluted soil), both species exhibited a clear avoidance response with all surviving earthworms retrieved (after 7 days) from the unpolluted soil. In a less polluted gradient (0%, 6.25%, 12.5%, 18.75%, 25%) L. rubellus were retrieved throughout the gradient while O. cyaneum were located within the 0% and 6.25% divisions, suggesting a species-specific response to polluted soil. Results also showed that the use of a linear pollution gradient system has the potential to assess earthworm avoidance behaviour and could provide a more ecologically relevant alternative to the ISO 17512: 2008 avoidance test. However, further work is required to establish the effectiveness of this procedure, specifically in initial chemical screening and assessment of single contaminant bioavailability, where uptake of pollutants by earthworms could be measured and directly related to the point of introduction and retrieval. PMID:26590693

  9. Evidence for avoidance of Ag nanoparticles by earthworms (Eisenia fetida).

    PubMed

    Shoults-Wilson, W A; Zhurbich, Oksana I; McNear, David H; Tsyusko, Olga V; Bertsch, Paul M; Unrine, Jason M

    2011-03-01

    Silver nanoparticles have been incorporated into a wide variety of consumer products, ideally acting as antimicrobial agents. Silver exposure has long been known to cause toxic effects to a wide variety of organisms, making large scale production of silver nanoparticles a potential hazard to environmental systems. Here we describe the first evidence that an organism may be able to sense manufactured nanoparticles in a complex, environmentally relevant exposure and that the presence of nanoparticles alters the organism's behavior. We found that earthworms (Eisenia fetida) consistently avoid soils containing silver nanoparticles and AgNO(3) at similar concentrations of Ag. However, avoidance of silver nanoparticles occurred over 48 h, while avoidance of AgNO(3) was immediate. It was determined that avoidance of silver nanoparticles could not be explained by release of silver ions or any changes in microbial communities caused by the introduction of Ag. This leads us to conclude that the earthworms were in some way sensing the presence of nanoparticles over the course of a 48 h exposure and choosing to avoid exposure to them. Our results demonstrate that nanoparticle interactions with organisms may be unpredictable and that these interactions may result in ecologically significant effects on behavior at environmentally relevant concentrations. PMID:21229389

  10. Contact tests for pentachlorophenol toxicity to earthworms

    SciTech Connect

    Spontak, D.A.

    1994-12-31

    The standardized contact filter paper test (EEC and OECD) provides an effective screening test for toxicity to earthworms in a laboratory setting. A need exists for a reliable and inexpensive technique for non-laboratory settings where screening is desired, but facilities cannot provide for the acquisition and maintenance of the glass vials required by the standardized test. This study evaluated two modifications of the standardized test using clear polyethylene bags, with and without filter paper, with Eisenia fetida and domesticated surface-feeding earthworms. The tests were conducted according to EEC and OECD guidelines. Results of the modified tests corresponded in dose and effect to the standardized contact filter paper test indicating the usefulness of the modified tests.

  11. Avoidance behaviour of two eco-physiologically different earthworms (Eisenia fetida and Aporrectodea caliginosa) in natural and artificial saline soils.

    PubMed

    Owojori, O J; Reinecke, A J

    2009-04-01

    We studied the avoidance behaviour of Eisenia fetida and Aporrectodea caliginosa in OECD artificial soil spiked with NaCl and in natural saline soil (of varying ionic constitutions) collected from Robertson Experimental Farm (ROBS) in Western Cape, South Africa. For each organism, the ecotoxicological test was performed using a two-chamber test over a period of 48 h. The results showed that in the OECD soil, the avoidance EC50 (the concentration/electrical conductivity at which there is effect on 50% of the organisms) for A. caliginosa of 667 mg kg(-1) NaCl was lower than 1164 mg kg(-1) for E. fetida. Similarly in ROBS soil, the avoidance EC50 for A. caliginosa of 0.26 dS m(-1) was lower than 0.56 dS m(-1) in E. fetida. These results indicated that A. caliginosa showed better avoidance to salinity than E. fetida irrespective of soil types or ionic constitution. When compared with literature data, EC50 values in avoidance tests were either lower or comparable to those of reproduction, which was the most sensitive life-cycle parameter. The only exception was the EC50 value for avoidance of E. fetida in natural soil which was higher than for reproduction suggesting that the predictive value of the avoidance test for this species might be lower in natural soils. The variation in sensitivities of these earthworms could be as a result of differences in their eco-physiology. These findings suggest the relevance of the avoidance test as a suitable screening method showing first tendencies of saline stress on the habitat function of soils. PMID:19211128

  12. Survival, Reproduction, Avoidance Behavior and Oxidative Stress Biomarkers in the Earthworm Octolasion cyaneum Exposed to Glyphosate.

    PubMed

    Salvio, Carla; Menone, Mirta L; Rafael, Sergio; Iturburu, Fernando G; Manetti, Pablo L

    2016-03-01

    The massive use of glyphosate (GLY) in several countries has increased the interest in investigating its potential adverse effects in non-target organisms. The aim of the present study was to assess the potential effects in survival and reproduction; avoidance behavior and oxidative stress under short-term (48 h) and subchronic exposures (28 days) to GLY in the earthworm Octolasion cyaneum. After 48 h no significant changes in the behavior was observed. In addition, a lower catalase activity at 498 μg GLY kg(-1) dry soil section relative to earthworms from the control section was obtained. After 28 days of exposure inhibition of glutathione S-transferase activity was observed at 535 μg GLY kg(-1) dry soil while no changes in the other endpoints were detected. These results indicate that environmentally relevant concentrations of GLY (up to 996 µg GLY kg(-1) dry soil) did not exert a toxic effect to O. cyaneum. PMID:26754543

  13. Relating results from earthworm toxicity tests to agricultural soil

    USGS Publications Warehouse

    Beyer, W.N.

    1992-01-01

    The artificial soil tests of the European Economic Community and of the Organization for Economic Cooperation produce data relating earthworm mortality to pesticide concentrations in soil under laboratory conditions. To apply these results to agricultural soils it is necessary to relate these concentrations to amounts of pesticide applied per area. This paper reviews the relevant published literature and suggests a simple relation for regulatory use. Hazards to earthworms from pesticides are suggested to be greatest soon after application, when the pesticides may be concentrated in a soil layer a few millimeters thick. For estimating exposure of earthworms, however, a thicker soil layer should be considered, to account for their movement through soil. During favorable weather conditions, earthworms belonging to species appropriate to the artificial soil test have been reported to confine their activity to a layer about 5 cm. If a 5-cm layer is accepted as relevant for regulatory purposes, then an application of 1 kg/ha would be equivalent to 1-67 ppm (dry) in the artificial soil test.

  14. Avoiding Unnecessary Preoperative Testing.

    PubMed

    Rusk, Matthew H

    2016-09-01

    Given the low-risk nature of cataract surgery, no preoperative testing is indicated unless the patient needs it for another reason. Although electrocardiograms may have a role in preoperative testing in patients at high risk of cardiovascular disease, or if the procedure carries with it significant operative risks, they are often unnecessary. Urinalysis and coagulation studies not should be routine because they have not shown any value in predicting complications. Although these tests are not individually expensive, the aggregate cost is substantial. As good stewards of the medical system, physicians need to use these tests more judiciously. PMID:27542420

  15. Feasibility of vermicomposting dairy biosolids using a modified system to avoid earthworm mortality.

    PubMed

    Nogales, R; Elvira, C; Benítez, E; Thompson, R; Gomez, M

    1999-01-01

    A laboratory study was conducted to examine the feasibility of vermicomposting dairy biosolids (dairy sludge), either alone or with either of the bulking agents-cereal straw or wood shavings, using the epigeic earthworm-Eisinea andrei. Earthworms added directly to these three substrates died within 48 hours. A system was developed to overcome the toxic effect of unprocessed dairy biosolids. The substrates were placed over a layer of vermicomposted sheep manure into which the earthworms were inoculated. Within two weeks, all earthworms were within the upper layer of substrate. Compared to sheep manure which is a favourable substrate for vermicomposting, the three substrates containing dairy biosolids were more effective in supporting earthworm growth and reproduction. The final products obtained after 63 days of vermicomposting had 39-53% less organic carbon than the initial substrates. Organic fractionation indicated that vermicomposting increased the stability of the materials to biological decomposition. The vermicomposts obtained from the three substrates with dairy biosolids had low heavy metal contents and electrical conductivities, and did not inhibit plant growth when compared with a commercial vermicompost in a bioassay. PMID:10048210

  16. Comparative avoidance behaviour of the earthworm Eisenia fetida towards chloride, nitrate and sulphate salts of Cd, Cu and Zn using filter paper and extruded water agar gels as exposure media.

    PubMed

    Demuynck, Sylvain; Lebel, Aurélie; Grumiaux, Fabien; Pernin, Céline; Leprêtre, Alain; Lemière, Sébastien

    2016-07-01

    We studied the avoidance behaviour of the earthworm Eisenia fetida towards Cd, Cu, and Zn, trace elements (TEs) tested as chloride, nitrate and sulphate salts. Sub adults were exposed individually using dual-cell chambers at 20+2°C in the dark. Recordings were realised at different dates from 2h to 32h. We used filter paper and extruded water agar gel as exposure media to evaluate the contribution of the dermal and the digestive exposure routes on the avoidance reactions. Exposures to Cu or Cd (10mgmetal ionL(-1)) resulted in highly significant avoidance reactions through the exposure duration. Worms avoided Zn poorly and reactions towards Zn salts varied along the exposure. Worm sensitivity towards TEs differed between salts and this could result from differential toxicity or accessibility of these TE salts to earthworms. The anion in itself was not the determinant of the avoidance reactions since exposures to similar concentrations of these anions using calcium salts did not result in significant avoidance worm behaviour. Avoidance responses towards TEs were higher in the case of water agar exposures than in filter paper exposures. Thus, dermal contacts with TE solutions would elicit worm avoidance but signals from receptors located inside the digestive tract could reinforce this behaviour. The use of extruded water agar gels as the substrate allows checking the real sensitivity of earthworm species towards TEs since the TE concentrations leading to significant avoidance reactions were below those reported in the literature when using TE-spiked soils. PMID:26995062

  17. The soil-dwelling earthworm Allolobophora chlorotica modifies its burrowing behaviour in response to carbendazim applications.

    PubMed

    Ellis, Sian R; Hodson, Mark E; Wege, Philip

    2010-09-01

    Carbendazim-amended soil was placed above or below unamended soil. Control tests comprised two layers of unamended soil. Allolobophora chlorotica earthworms were added to either the upper or the unamended soil. After 72 h vertical distributions of earthworms were compared between control and carbendazim-amended experiments. Earthworm distributions in the carbendazim-amended test containers differed significantly from the 'normal' distribution observed in the control tests. In the majority of the experiments, earthworms significantly altered their burrowing behaviour to avoid carbendazim. However, when earthworms were added to an upper layer of carbendazim-amended soil they remained in this layer. This non-avoidance is attributed to (1) the earthworms' inability to sense the lower layer of unamended soil and (2) the toxic effect of carbendazim inhibiting burrowing. Earthworms modified their burrowing behaviour in response to carbendazim in the soil. This may explain anomalous results observed in pesticide field trials when carbendazim is used as a control substance. PMID:20580088

  18. ACAT Ground Collision Avoidance Flight Tests Over

    NASA Video Gallery

    NASA's Dryden Flight Research Center has concluded flight tests of an Automatic Ground Collision Avoidance System (Auto GCAS) under the joint U.S. Air Force/NASA F-16D Automatic Collision Avoidance...

  19. Flight Tests Validate Collision-Avoidance System

    NASA Video Gallery

    Flights tests of a smartphone-assisted automatic ground collision avoidance system at NASA's Dryden Flight Research Center consistently commanded evasive maneuvers when it sensed that the unmanned ...

  20. Effects of silver nanoparticles and silver nitrate in the earthworm reproduction test.

    PubMed

    Schlich, Karsten; Klawonn, Thorsten; Terytze, Konstantin; Hund-Rinke, Kerstin

    2013-01-01

    The widespread use of silver nanoparticles (Ag-NPs), for example, in textiles and cleaning products, means that they are likely to reach the environment via biosolids or the effluent from wastewater treatment plants. The aim of the present study was to determine the ecotoxicity of Ag-NPs in the earthworm reproduction test using Eisenia andrei. In addition to the usual endpoints, the authors also investigated the uptake and accumulation of Ag by adult earthworms and the concentration of free Ag(+) in soil pore water. Silver nanoparticles and Ag nitrate showed similar toxicities in the earthworm reproduction test. The uptake of Ag from Ag-NPs in the earthworm was slightly higher than the uptake of Ag from Ag nitrate. Spiked soils showed a concentration-dependent effect on reproduction, but there was no concentration-dependent increase in the amount of Ag in earthworm tissues. The authors noted a concentration-dependent increase in the levels of free Ag(+) in the soil pore water regardless of the Ag source. The number of juveniles is a more suitable endpoint than biomass or mortality. The uptake of Ag does not appear to inhibit reproduction. Instead, inhibition seems to reflect Ag(+) released into the soil pore water, which affects cocoons and juveniles in the soil. Analysis of transformed Ag-NPs after purification in wastewater treatment plants would provide additional information. PMID:23059754

  1. EVALUATION OF ALTERNATIVE REFERENCE TOXICANTS FOR USE IN THE EARTHWORM TOXICITY TEST

    EPA Science Inventory

    The use of the 14-d earthworm toxicity test to aid in the evaluation of the ecological impact of contaminated soils is becoming increasingly widespread. However,the method is in need of further standardization. As part of this continuing process, the choice of reference toxicants...

  2. Toxicity of the ionophore antibiotic lasalocid to soil-dwelling invertebrates: avoidance tests in comparison to classic sublethal tests.

    PubMed

    Žižek, Suzana; Zidar, Primož

    2013-07-01

    Lasalocid is a veterinary ionophore antibiotic used for prevention and treatment of coccidiosis in poultry. It enters the environment with the use of contaminated manure on agricultural land. Despite its extensive use, the effects of lasalocid on non-target soil organisms are poorly explored. We used classical subleathal ecotoxicity tests to assess the effects of lasalocid on earthworms (Eisenia andrei) and isopods (Porcellio scaber) and compared the results with tests using avoidance behaviour as the endpoint. The results showed that avoidance is a much more sensitive endpoint. For earthworms, EC50 for avoidance (12.3 mg kg(-1) dry soil) was more than five times lower than EC50 for reproduction (69.6 mg kg(-1) dry soil). In isopods the sensitivity of the behavioural response test was even higher. While the highest lasalocid concentration 202 mg kg(-1) had no significant effects on isopod growth or survival, already the lowest used concentration in the behavioural assay (4.51 mg kg(-1)) caused significant impact on isopod behaviour. Using the avoidance test results for calculating the predicted no-effect concentration (PNEC) of lasalocid to soil invertebrates, the value is close to the predicted environmental concentration (PEC). This indicates that the use of lasalocid-contaminated manure could potentially impair the habitat function of agricultural soils. PMID:23635534

  3. Depleted uranium mobility across a weapons testing site: isotopic investigation of porewater, earthworms, and soils.

    PubMed

    Oliver, Ian W; Graham, Margaret C; MacKenzie, Angus B; Ellam, Robert M; Farmer, John G

    2008-12-15

    The mobility and bioavailability of depleted uranium (DU) in soils at a UK Ministry of Defence (UK MoD) weapons testing range were investigated. Soil and vegetation were collected near a test-firing position and at eight points along a transect line extending approximately 200 m down-slope, perpendicular to the firing line, toward a small stream. Earthworms and porewaters were subsequently separated from the soils and both total filtered porewater (<0.2 microm) and discrete size fractions (0.2 microm-100 kDa, 100-30 kDa, 30-3 kDa, and <3 kDa)obtainedvia centrifugal ultrafiltration were examined. Uranium concentrations were determined by inductively coupled plasma optical emission spectrometry (ICP-OES) for soils and ICP-mass spectrometry (MS) for earthworms and porewaters, while 235U:238U atom ratios were determined by multicollector (MC)-ICP-MS. Comparison of the porewater and earthworm isotopic values with those of the soil solids indicated that DU released into the environment during weapons test-firing operations was more labile and more bioavailable than naturally occurring U in the soils at the testing range. Importantly, DU was shown to be present in soil porewater even at a distance of approximately 185 m from the test-firing position and, along the extent of the transect was apparently associated with organic colloids. PMID:19174886

  4. Contact and artificial soil tests using earthworms to evaluate the impact of wastes in soil

    SciTech Connect

    Neuhauser, E.F.; Loehr, R.C.; Malecki, M.R.

    1986-01-01

    The study was designed to evaluate two methods using earthworms that can be used to estimate the biological impact of organic and inorganic compounds that may be in wastes applied to land for treatment and disposal. The two methods were the contact test and the artificial soil test. The contact test is 48-h test using an adult worm, a small glass vial, and filter paper to which the test chemical or waste is applied. The test is designed to provide close contact between the worm and a chemical, similar to the situation in soils. The method provides a rapid estimate of the relative toxicity of chemicals and industrial wastes.

  5. Acute and chronic toxicity testing of TPH-contaminated soils with the earthworm, Eisenia foetida

    SciTech Connect

    Stewart, A.J.; Wicker, L.F.; Nazerias, M.S.

    1995-12-31

    Responses of Eisenia foetida to petroleum-contaminated soils are being assessed using a 21-day test described previously. The authors prepared dilutions of two soils, referred to as A and B, using their reference-soil counterparts, collected from near the contaminated sites. The total petroleum hydrocarbon (TPH) content of each soil was measured by latroscan before the dilutions were prepared. References for the A and B soils contained 167 and 1,869 ppm of TPH, respectively. Thus, neither reference soil was pristine. Dilutions of the A soil tested with E. foetida contained from 179 to 305 ppm TPH; dilutions of the B soil contained from 1,875 to 1,950 ppm TPH. E foetida survival was 100% in both dilution series. Mean growth of Eisenia in dilutions of the A soil ranged from 48 to 74 mg dry-weight growth per pair of worms; these values were lower than those in any dilution of the B soil series. Lipid levels of worms in higher concentrations of the A and B soils were similar to one another and to published values, suggesting little inhibition of feeding in either dilution series. Earthworm reproduction was zero in the A series, but moderately high in the B series. Thus, the A soil apparently contained materials other than TPH that inhibited earthworm growth and reproduction. This study shows that (1) TPH at concentrations as high as 1,800 ppm may not always be inhibitor to earthworm growth or reproduction and (2) that earthworm survival, as a test endpoint, is much less sensitive than either growth or reproduction.

  6. Contact Dermatitis, Patch Testing, and Allergen Avoidance.

    PubMed

    Burkemper, Nicole M

    2015-01-01

    In patients presenting with a complaint of rash, contact dermatitis is often the underlying diagnosis making it an entity with which health care providers should be familiar. Contact dermatitis can be divided into irritant contact dermatitis and allergic contact dermatitis. In a patient suspected of having allergic contact dermatitis, patch testing can be done to identify specific allergens. Education focused on allergen avoidance and safe products is an integral part of treatment for the contact dermatitis patient. Knowledge of the most common allergens is helpful for clinicians to be able to provide this education. PMID:26455061

  7. Development of a suitable test method for evaluating the toxicity of contaminated soils to earthworms in Canada

    SciTech Connect

    Stephenson, G.L.; Scroggins, R.

    1995-12-31

    Environment Canada has embarked on a five year program to develop, standardize, and validate a battery of soil toxicity tests which can be used to assess the relative toxicity of contaminants in soils to terrestrial organisms. These tests must be applicable to soil conditions typically found in Canadian environments and the test species must be representative of the species of soil invertebrates or plants inhabiting soil ecosystems in Canada. One of the toxicity tests being developed is designed to assess the toxicity of contaminated soils to earthworms. Five of the potential test species belong to the Lumbricidae family and include the Canadian worm (Allobophora calignosa/Aporrectodea tuberculate), the European bark worm (Dendrodtilus rubidus (rubida)), the pink soil worm (Eisenia rosea), the red marsh worm (Lumbricus rubellus), and the Canadian night crawler or dew worm (Lumbricus terrestris). The sixth species, the white pot worm (Enchytraeus albidus), belongs to the Enchytraeidae family. Further assessment reduced the number of representative species to three. Most earthworm test methods have been developed to assess the toxicity of chemically-spiked artificial soils to Eisenia fetida or E. andrei. Test methods have also been developed to assess the relative toxicity of contaminated soils from hazardous waste sites. Comparative acute toxicity data for three species of earthworm exposed to a hydrocarbon contamination will be presented. Comparative toxicity data for the same three species of earthworm will also be presented using test procedures and conditions that have been modified to accommodate biological differences among the species of earthworm. Recommendations regarding test design, methods, and conditions optimal for each test species will be summarized and discussed with respect to the precision of test results.

  8. Biochemical and genotoxic effect of triclosan on earthworms (Eisenia fetida) using contact and soil tests.

    PubMed

    Lin, Dasong; Xie, Xiujie; Zhou, Qixing; Liu, Yao

    2012-07-01

    Triclosan (TCS) is a broad-spectrum bactericide that is used for a variety of antimicrobial functions. TCS is frequently detected in the terrestrial environment due to application of sewage sludge to agricultural land. In the present study, 48-h paper contact and 28-day spiked soil tests were conducted to examine the toxic effects of TCS on the antioxidative and genetic indices of earthworms (Eisenia fetida). The activity of antioxidative enzymes (superoxide dismutase, SOD; catalase, CAT) and the content of the lipid peroxidation product (malondialdehyde, MDA) were determined as biomarkers of oxidative stress in E. fetida. Moreover, single cell gel electrophoresis (SCGE) was used as a biomarker of genotoxicity. The results showed that triclosan induced a significant increase (P < 0.05) in antioxidative enzyme activities and MDA content. Of all of the biomarkers examined, CAT activity was most sensitive to TCS, and the CAT activity increased significantly (P < 0.05) at bactericidal concentrations of 7.86 ng cm⁻² in the contact test and 10 mg kg⁻¹ in the spiked soil test. The comet assay showed that TCS treatments significantly induced (P < 0.05) DNA damage in E. fetida, and that 78.6 ng cm⁻² caused significant genotoxic effects in the acute test (48 h). Clear dose-dependent DNA damage to E. fetida was observed both in contact and spiked soil tests. These results imply that TCS may have potential biochemical and genetic toxicity toward earthworms (E. fetida). A battery of biomarkers covering multiple molecular targets of acute toxicity can be combined to better understand the impacts of TCS on E. fetida. PMID:22707219

  9. Searching for a more sensitive earthworm species to be used in pesticide homologation tests - a meta-analysis.

    PubMed

    Pelosi, C; Joimel, S; Makowski, D

    2013-01-01

    Pesticide risk assessments include experiments designed to measure the effect of pesticides on earthworms using the Eisenia fetida fetida or Eisenia fetida andrei species. There is no clear consensus in the literature on the sensitivity of different earthworm species to pesticides. We performed a meta-analysis on the sensitivity of several earthworm species to pesticides to determine the most sensitive species, and to discuss their suitability for European homologation tests. A dataset including median lethal dose (LC50) values reported in 44 experimental treatments was constructed and then analyzed in order to compare the sensitivity levels of E. fetida with that of other earthworm species. Results showed that LC50 values reported for Lumbricus terrestris and Aporrectodea caliginosa were on average significantly lower than for E. fetida. Considering the relatively high LC50 values reported for E. fetida and the absence of this species from zones where pesticides are usually applied, the relevance of using E. fetida for pesticide homologation tests is questionable and we advise risk assessors to use A. caliginosa as model species. A new protocol based on this species could be proposed for European homologation tests but its implementation will require the definition of a new standard and take time. In the meantime, the results obtained with E. fetida should be interpreted with caution taking into account the low sensitivity of this species. Our study illustrates the value of the meta-analysis approach for comparing the sensitivity of different earthworm species to pesticides. It would be useful to extend the dataset presented in this paper in order to analyze the sensitivity of other aquatic or terrestrial organism groups used for pesticide homologation or ecotoxicology tests. PMID:23084259

  10. Twenty Common Testing Mistakes for EFL Teachers to Avoid

    ERIC Educational Resources Information Center

    Henning, Grant

    2012-01-01

    To some extent, good testing procedure, like good language use, can be achieved through avoidance of errors. Almost any language-instruction program requires the preparation and administration of tests, and it is only to the extent that certain common testing mistakes have been avoided that such tests can be said to be worthwhile selection,…

  11. Biomarker responses in earthworm Eisenia andrei exposed to pirimiphos-methyl and deltamethrin using different toxicity tests.

    PubMed

    Velki, Mirna; Hackenberger, Branimir K

    2013-01-01

    The effects of two widely used insecticides - organophosphate pirimiphos-methyl and pyrethroid deltamethrin - were investigated under laboratory conditions following OECD guidelines using the epigeic earthworm Eisenia andrei as the test organism. The overall aim of this study was to evaluate the effects of these pesticides on molecular biomarkers of earthworm E. andrei using the in vitro, filter paper contact and artificial soil test. In this study for the first time the equivalent concentrations of investigated pesticide applied in different tests were calculated. Although the response of measured molecular biomarkers in different toxicity tests had certain similarities, some distinct differences were also evident. Both pesticides inhibited AChE and CES activities in all three applied toxicity tests; however only in the filter paper test the hormetic effect was recorded. The artificial soil test showed that duration of the exposure significantly changed the effects of the investigated pesticides on CAT and GST activities. Namely, after the initial increase, the prolongation of exposure caused the reduction of the CAT and GST activities. Both pesticides significantly inhibited the efflux pump activity. In the artificial soil test, the significant changes in measured biomarkers after application of doses lower than doses recommended for use in the agriculture indicate that the investigated pesticides could have a harmful effect on earthworms in the context of the realistic environment. PMID:23063481

  12. Joint Detect and Avoid Flight Testing

    NASA Technical Reports Server (NTRS)

    Maliska, Heather; Estrada, Ramon; Euteneuer, Eric; Gong, Chester; Arthur, Keith

    2015-01-01

    This presentation gives insight into a joint flight testing effort that included participation from NASA, Honeywell, and General Atomics. The presentation includes roles and responsibilities, test flow, and encounter requirements and summary.

  13. Evaluation of alternative reference toxicants for use in the earthworm toxicity test

    SciTech Connect

    Yeardley, R.B. Jr.; Lazorchak, J.M.; Pence, M.A.

    1995-07-01

    The use of the 14-d earthworm toxicity test to aid in the evaluation of the ecological impact of contaminated soils is becoming increasingly widespread. However, the method is in need of further standardization. As part of this continuing process, the choice of reference toxicants was evaluated. Reference toxicants were rated in relation to the following criteria: (a) reproducibility, (b) low human health hazard, (c) feasibility of measurement, and (d) chemical stability. Potassium chloride (KCl) and ammonium chloride (NH{sub 4}Cl) were evaluated as possible alternatives to the one currently in common use, 2-chloroacetamide. Potassium chloride rated the best for the combination of the four criteria, followed by NH{sub 4}Cl and 2-chloroacetamide. Coefficients of variation (C.V.s) from control charts of six definitive tests were use to measure reproducibility. The best reproducibility (lowest C.V.) was shown by KCl, followed by NH{sub 4}Cl and 2-chloroacetamide. Toxicants ranked KCl < NH{sub 4}Cl {much_lt} 2-chloroacetamide in terms of health hazard; and KCl = NH{sub 4}Cl > 2-chloroacetamide in terms of measurement feasibility. Both 2-chloroacetamide and NH{sub 4}Cl changed in concentration during testing. Evidence is also presented that 2-chloroacetamide degrades rapidly during testing, and that, as dead worms decay, ammonification may be adding another toxicant, ammonia, to tests.

  14. Ring-testing and field-validation of a terrestrial model ecosystem (TME)--an instrument for testing potentially harmful substances: effects of carbendazim on earthworms.

    PubMed

    Römbke, Jörg; Van Gestel, Cornelis A M; Jones, Susan E; Koolhaas, Josée E; Rodrigues, José M L; Moser, Thomas

    2004-01-01

    The effects of the fungicide carbendazim (applied in the formulation Derosal) on earthworms (Lumbricidae) was determined in Terrestrial Model Ecosystem (TME) tests and field-validation studies. TMEs consisted of intact soil columns (diameter 17.5 cm; length 40 cm) taken from a grassland or, in one case, from an arable site. The TMEs were taken from the same site where the respective field-validation study was performed. The tests were performed in Amsterdam (The Netherlands), Bangor (Wales, UK), Coimbra (Portugal) and Flörsheim (Germany). The sites selected had an earthworm coenosis representative of the different land use types and regions. In addition, the differences between the coenosis found in the TMEs and the respective field sites were in general low. A high variability was found between the replicate samples, which reduces the probability of determining significant differences by the statistical evaluation of the data. Similar effects of the chemical treatment were observed on abundance as well as on biomass. Effects were most pronounced 16 weeks after application of the test chemical. The observed effects on earthworm abundance and biomass did not differ between the TME tests and the respective field-validation studies. Effects on earthworm diversity were difficult to assess since the number of individuals per species was low in general. However, the genus Lumbricus and in particular L. terrestris and L. rubellus seemed to be more affected by the chemical treatment than others. NOEC and EC50-values derived from the TME pre-test, the TME ring-test and the field-validation study indicate that the TMEs of the different partners delivered comparable results although different soils were used. Due to the high variability NOECs could often not be determined. The EC50-values for the effect of carbendazim on earthworm abundance ranged between 2.04 and 48.8 kg a.i./ha (2.71-65.2 mg/kg soil) and on earthworm biomass from 1.02 to 34.6 kg a.i./ha (1.36-46.0 mg

  15. Development of a standardized reproduction toxicity test with the earthworm species Eisenia fetida andrei using copper, pentachlorophenol and 2,4-dichloroaniline

    SciTech Connect

    van Gestel, C.A.; van Dis, W.A.; van Breemen, E.M.; Sparenburg, P.M. )

    1989-12-01

    This article describes a standardized test method for determining the effect of chemical substances on the reproduction of the earthworm Eisenia fetida andrei. It is based on the existing guidelines for acute toxicity testing with earthworms, and for reasons of standardization the same artificial soil substrate and earthworm species were chosen as prescribed by these guidelines. After being preconditioned for one week in untreated soil, earthworms are exposed to the chemical substances for 3 weeks. The number of cocoons produced is determined, and cocoons are incubated in untreated artificial soil for 5 weeks to assess hatchability. Results are presented from toxicity experiments with pentachlorophenol, copper, and 2,4-dichloroaniline. For these compounds no-effect levels (NEL) for cocoon production were 32, 60-120, and 56 mg.kg-1 dry soil, respectively. Hatching of cocoons was influenced by pentachlorophenol (NEL, 10 mg.kg-1), but not by copper and dichloroaniline. Following exposure, earthworms were incubated in clean soil again to study the possibility of recovery of cocoon production. For copper and dichloroaniline earthworms did recover cocoon production to a level as high as the control level or even higher; in case of pentachlorophenol, cocoon production was still reduced after 3 weeks in clean soil.

  16. Comparison of sublethal and lethal criteria for nine different chemicals in standardized toxicity tests using the earthworm Eisenia andrei

    SciTech Connect

    Van Gestel, C.A.; Dirven-Van Breemen, E.M.; Baerselman, R.; Emans, H.J.; Janssen, J.A.; Postuma, R.; Van Vliet, P.J. )

    1992-04-01

    In this study, the effects of nine different chemicals on the survival, growth, and reproduction of the earthworm species Eisenia andrei were determined using a recently developed method. Earthworms were exposed for 3 weeks to the test chemicals in an artificial soil substrate. Additional data on the acute toxicity of these chemicals were derived from the literature. For some chemicals, cocoon production was the most sensitive parameter (cadmium, chromium, paraquat, fentin, benomyl, phenmedipham), while for others cocoon hatchability was most sensitive (pentachlorophenol, parathion, carbendazim). In the case of parathion, growth of the worms seemed to be even more sensitive than reproduction. As an overall parameter for the effect on earthworm reproduction, the total number of juveniles produced per worm appeared to be a useful parameter. Differences between (acute) LC50 values and the lowest NOEC value for effects on growth and reproduction were different for each chemical. Difference was greatest for cadmium (a factor of greater than 100) and smallest for fentin, benomyl, and pentachlorophenol (a factor of 5-6).

  17. Avoidance-preference testing in density stratified solutions

    SciTech Connect

    Smith, E.H.; Logan, D.T.; Hansen, S.

    1994-12-31

    Toxicity testing is sometimes required where density stratifies test and reference solutions. Examples include freshwater effluents that float in estuarine and marine waters and desalinating plant effluents that sink. Standard avoidance-preference testing methods and apparatus are designed to test horizontal rather than vertical gradients and so are inappropriate for density stratified solutions. To overcome associated deficiencies, the authors modified testing chambers to take advantage of density stratification. Exposure levels for tests were selected based on NOELs from standard toxicity testing. Behavior of 10 striped bass was simultaneously observed using electronic surveillance. Measure of behavior include position in two axes and swimming speed. Avoidance-preference between several types of high density byproducts of salt water evaporation and lower density receiving water were tested. Results indicate that the modified test protocols allowed the authors to determine behavior responses to test materials.

  18. Improvement of the applicability of ecotoxicological tests with earthworms, springtails, and plants for the assessment of metals in natural soils.

    PubMed

    Römbke, Jorg; Jänsch, Stephan; Junker, Thomas; Pohl, Britta; Scheffczyk, Adam; Schallnass, Hans-Joachim

    2006-03-01

    The environmental risk assessment of metals in the soil compartment is based mainly on tests performed in Organization for Economic Cooperation and Development (OECD) artificial soil, but ecologically, the use of natural soils would be more relevant. In this contribution, the reproduction and growth of three standard species (an earthworm, a collembolan, and a dicotyledonous plant, respectively) was evaluated in nine natural soils (covering a wide range of pH values, organic matter content, texture, and so on) and in OECD artificial soil. Afterward, the effects of the model chemical zinc nitrate were assessed in all soils that were identified as being suitable for these species. The test results indicate that the toxicity of zinc nitrate can be higher by a factor of approximately four compared to artificial soil for invertebrates (earthworms and collembolans), whereas plants are only slightly more sensitive in some natural soils than in artificial soil. When comparing the different endpoints, it could be confirmed that the median effective concentration (EC50) is the most robust compared to the highly uncertain 10% effective concentration. Decreasing toxicity of zinc nitrate to collembolans was significantly correlated with an increase in soil pH but not with cation exchange capacity (CEC) or organic carbon (OC) content. No significant correlation was found between the toxicity of zinc nitrate to earthworms or plants and soil pH, CEC, or OC content. Possible consequences of the results are discussed, such as the testing of natural soils in addition to the OECD artificial soil or the inclusion of an additional safety factor to use the EC50 in current risk assessment schemes focusing on no-observed-effect concentrations. PMID:16566163

  19. COMPARATIVE TOXICITY OF TEN ORGANIC CHEMICALS TO FOUR EARTHWORM SPECIES

    EPA Science Inventory

    Ten organic chemicals were tested for toxicity to four earthworm species: Allolobophora tuberculata, Eisenia fetida, Eudrilus eugeniae and Perionyx excavatus, using the European Economic Community's (EEC) earthworm artificial soil and contact testing procedure. The phenols were t...

  20. Preliminary evidence of differences in cadmium tolerance in metal-free stocks of the standard earthworm test species Eisenia andrei (Oligochaeta).

    PubMed

    Otomo, Patricks Voua; Otomo, Laetitia Voua; Bezuidenhout, Carlos C; Maboeta, Mark S

    2016-08-01

    To test whether metal-tolerant and metal-sensitive earthworm specimens could be an inherent part of metal-free earthworm populations, (i) we used DNA barcoding to identify and categorize earthworms from 8 populations of the standard test species Eisenia andrei, and (ii) the earthworms carrying three of the identified COI haplotypes (named Hap1, hap3 and Hap3) were paired up and exposed to Cd in order to assess the difference in Cd sensitivity between the breeding pairs. A total of six breeding pairs were exposed to 0, 25, 50 and 100 mg Cd/kg for 4 weeks at 20 °C. The survival of the breeding pairs, their change in biomass and cocoon production were assessed. For all of the endpoints assessed, the results indicated that couple 6 (Hap3 × Hap3) was the most sensitive breeding pair whereas couple 4 (Hap1 × Hap3) was the least sensitive one. The analysis of Cd tissue contents revealed that with increasing Cd concentration, Cp6 (Hap3 × Hap3) could accumulate significantly more Cd than any other breeding pair (p ≤ 0.01). Our findings indicate that E. andrei may harbour intrinsically Cd-tolerant and Cd-sensitive individuals and that this may be due to individual differences in Cd accumulation kinetics. In the context of ecotoxicological testing, our results underline the importance of using genetically diverse populations in laboratory testing to prevent generating flawed data from genetically homogeneous laboratory stocks. Although we do not regard the present mitochondrial haplotypes as proxy for possibly nuclear encoded traits, we discuss the necessity of a standardised earthworm barcoding protocol that could help not only to confirm the taxonomy of laboratory earthworm stocks but also to select genetically diverse stocks suitable for laboratory testing. PMID:27151404

  1. Legacy of earthworms' engineering effects enlarges the actual effects of earthworms on plants

    NASA Astrophysics Data System (ADS)

    Mudrák, Obdřej; Frouz, Jan

    2015-04-01

    Earthworms were recognized as key factor responsible for changes from early to late successional plant communities. They incorporate organic matter into the soil and creates there persistent structures, which improves conditions for plant growth. Earthworm activity might be therefore expected to be more important in early stages of the succession, when earthworm colonization of previously earthworm free soil starts, than in the late stages of the succession, where the soil was previously modified by earthworms. However, earthworms affect plants also via other effects such as increase of nutrient availability. The relative importance of soil structure modification and other earthworm effects on plants is poorly known, despite it is important for both theoretical and applied ecology. To test the effect of earthworms (Lumbricus rubellus and Aporrectodea caliginosa) on plants we performed microcosm laboratory experiment, where earthworms were affecting early successional (Poa compressa, Medicago lupulina, and Daucus carota) and late successional (Arrhenatherum elatius, Lotus corniculatus, and Plantago laceolata) plat species in soil previously unaffected by earthworms and in soil with previous long term effect of earthworms. These soils were taken from the early and late successional monitoring sites of the Sokolov coal mining district with known history. Earthworms increased plant biomass proportionally more in late successional soil. It was mainly because they increased availability of nutrients (nitrate and potassium) and plants get higher advantage out of this in late successional soil. Earthworms increased plant biomass of both early and late successional species, but late successional species suppressed early successional species in competition. This suppression was more intensive in presence of earthworms and in late successional soil. We therefore found multiplicative effect between earthworm soil engineering activity and their other effects, which might be

  2. Herbivory of an invasive slug is affected by earthworms and the composition of plant communities

    PubMed Central

    2013-01-01

    Background Biodiversity loss and species invasions are among the most important human-induced global changes. Moreover, these two processes are interlinked as ecosystem invasibility is considered to increase with decreasing biodiversity. In temperate grasslands, earthworms serve as important ecosystem engineers making up the majority of soil faunal biomass. Herbivore behaviour has been shown to be affected by earthworms, however it is unclear whether these effects differ with the composition of plant communities. To test this we conducted a mesocosm experiment where we added earthworms (Annelida: Lumbricidae) to planted grassland communities with different plant species composition (3 vs. 12 plant spp.). Plant communities had equal plant densities and ratios of the functional groups grasses, non-leguminous forbs and legumes. Later, Arion vulgaris slugs (formerly known as A. lusitanicus; Gastropoda: Arionidae) were added and allowed to freely choose among the available plant species. This slug species is listed among the 100 worst alien species in Europe. We hypothesized that (i) the food choice of slugs would be altered by earthworms’ specific effects on the growth and nutrient content of plant species, (ii) slug herbivory will be less affected by earthworms in plant communities containing more plant species than in those with fewer plant species because of a more readily utilization of plant resources making the impacts of earthworms less pronounced. Results Slug herbivory was significantly affected by both earthworms and plant species composition. Slugs damaged 60% less leaves when earthworms were present, regardless of the species composition of the plant communities. Percent leaf area consumed by slugs was 40% lower in communities containing 12 plant species; in communities containing only three species earthworms increased slug leaf area consumption. Grasses were generally avoided by slugs. Leaf length and number of tillers was increased in mesocosms

  3. Bioaccumulation of polycyclic aromatic hydrocarbons and survival of earthworms (Eisenia andrei) exposed to biochar amended soils.

    PubMed

    Malev, O; Contin, M; Licen, S; Barbieri, P; De Nobili, M

    2016-02-01

    Biochar has a charcoal polycyclic aromatic structure which allows its long half-life in soil, making it an ideal tool for C sequestration and for adsorption of organic pollutants, but at the same time raises concerns about possible adverse impacts on soil biota. Two biochars were tested under laboratory-controlled conditions on Eisenia andrei earthworms: a biochar produced at low temperature from wine tree cuttings (WTB) and a commercial low tar hardwood lump charcoal (HLB). The avoidance test (48-h exposure) showed that earthworms avoid biochar-treated soil with rates higher than 16 t ha(-1) for HLB and 64 t ha(-1) for WTB. After 42 days, toxic effects on earthworms were observed even at application rates (100 t ha(-1)) that are generally considered beneficial for most crops. The concentration of HLB and WTB required to kill half of earthworms' population (LC50; 95% confidence limits) in the synthetic OECD soil was 338 and 580 t ha(-1), respectively. Accumulation of polycyclic aromatic hydrocarbons (PAH) in earthworms exposed to the two biochar types at 100 t ha(-1) was tested in two soils of different texture. In biochar-treated soils, the average earthworm survival rates were about 64% in the sandy and 78% clay-loam soils. PAH accumulation was larger in the sandy soil and largest in soils amended with HLB. PAH with less than four rings were preferentially scavenged from the soil by biochars, and this behaviour may mask that of the more dangerous components (i.e. four to five rings), which are preferentially accumulated. Earthworms can accumulate PAH as a consequence of exposure to biochar-treated soils and transfer them along the food chain. Soil type and biochar quality are both relevant in determining PAH transfer. PMID:26490928

  4. Sequential Probability Ratio Test for Collision Avoidance Maneuver Decisions

    NASA Technical Reports Server (NTRS)

    Carpenter, J. Russell; Markley, F. Landis

    2010-01-01

    When facing a conjunction between space objects, decision makers must chose whether to maneuver for collision avoidance or not. We apply a well-known decision procedure, the sequential probability ratio test, to this problem. We propose two approaches to the problem solution, one based on a frequentist method, and the other on a Bayesian method. The frequentist method does not require any prior knowledge concerning the conjunction, while the Bayesian method assumes knowledge of prior probability densities. Our results show that both methods achieve desired missed detection rates, but the frequentist method's false alarm performance is inferior to the Bayesian method's

  5. Sequential Probability Ratio Test for Spacecraft Collision Avoidance Maneuver Decisions

    NASA Technical Reports Server (NTRS)

    Carpenter, J. Russell; Markley, F. Landis

    2013-01-01

    A document discusses sequential probability ratio tests that explicitly allow decision-makers to incorporate false alarm and missed detection risks, and are potentially less sensitive to modeling errors than a procedure that relies solely on a probability of collision threshold. Recent work on constrained Kalman filtering has suggested an approach to formulating such a test for collision avoidance maneuver decisions: a filter bank with two norm-inequality-constrained epoch-state extended Kalman filters. One filter models the null hypotheses that the miss distance is inside the combined hard body radius at the predicted time of closest approach, and one filter models the alternative hypothesis. The epoch-state filter developed for this method explicitly accounts for any process noise present in the system. The method appears to work well using a realistic example based on an upcoming, highly elliptical orbit formation flying mission.

  6. Responses of earthworm to aluminum toxicity in latosol.

    PubMed

    Zhang, Jia'en; Yu, Jiayu; Ouyang, Ying; Xu, Huaqin

    2013-02-01

    Excess aluminum (Al) in soils due to acid rain leaching is toxic to water resources and harmful to soil organisms and plants. This study investigated adverse impacts of Al levels upon earthworms (Eisenia fetida) from the latosol (acidic red soil). Laboratory experiments were performed to examine the survival and avoidance of earthworms from high Al concentrations and investigate the response of earthworms upon Al toxicity at seven different Al concentrations that ranged from 0 to 300 mg kg(-1) over a 28-day period. Our study showed that the rate of the earthworm survival was 100 % within the first 7 days and decreased as time elapsed, especially for the Al concentrations at 200 and 300 mg kg(-1). A very good linear correlation existed between the earthworm avoidance and the soil Al concentration. There was no Al toxicity to earthworms with the Al concentration ≤ 50 mg kg(-1), and the toxicity started with the Al concentration ≥ 100 mg kg(-1). Low Al concentration (i.e., <50 mg kg(-1)) enhanced the growth of the earthworms, while high Al concentration (>100 mg kg(-1)) retarded the growth of the earthworms. The weight of earthworms and the uptake of Al by earthworms increased with the Al concentrations from 0 to 50 mg kg(-1) and decreased with the Al concentrations from 50 to 300 mg kg(-1). The protein content in the earthworms decreased with the Al concentrations from 0 to 100 mg kg(-1) and increased from 100 to 300 mg kg(-1). In contrast, the catalase (CAT) and superoxide dismutase (SOD) activities in the earthworms increased with the Al concentrations from 0 to 100 mg kg(-1) and decreased from 100 to 300 mg kg(-1). The highest CAT and SOD activities and lowest protein content were found at the Al concentration of 100 mg kg(-1). Results suggest that a high level of Al content in latosol was harmful to earthworms. PMID:22645004

  7. Adaptive Stress Testing of Airborne Collision Avoidance Systems

    NASA Technical Reports Server (NTRS)

    Lee, Ritchie; Kochenderfer, Mykel J.; Mengshoel, Ole J.; Brat, Guillaume P.; Owen, Michael P.

    2015-01-01

    This paper presents a scalable method to efficiently search for the most likely state trajectory leading to an event given only a simulator of a system. Our approach uses a reinforcement learning formulation and solves it using Monte Carlo Tree Search (MCTS). The approach places very few requirements on the underlying system, requiring only that the simulator provide some basic controls, the ability to evaluate certain conditions, and a mechanism to control the stochasticity in the system. Access to the system state is not required, allowing the method to support systems with hidden state. The method is applied to stress test a prototype aircraft collision avoidance system to identify trajectories that are likely to lead to near mid-air collisions. We present results for both single and multi-threat encounters and discuss their relevance. Compared with direct Monte Carlo search, this MCTS method performs significantly better both in finding events and in maximizing their likelihood.

  8. Reproductive and behavioral responses of earthworms exposed to nano-sized titanium dioxide in soil.

    PubMed

    McShane, Heather; Sarrazin, Manon; Whalen, Joann K; Hendershot, William H; Sunahara, Geoffrey I

    2012-01-01

    Nanometer-sized titanium dioxide (nano-TiO(2) ) is found in a number of commercial products; however, its effects on soil biota are largely unknown. In the present study, earthworms (Eisenia andrei and Eisenia fetida) were exposed to three types of commercially available, uncoated TiO(2) nanomaterials with nominal diameters of 5, 10, and 21 nm. Nanomaterials were characterized for particle size, agglomeration, surface charge, chemical composition, and purity. Standard lethality, reproduction, and avoidance tests, as well as a juvenile growth test, were conducted in artificial soil or field soil amended with nano-TiO(2) by two methods, liquid dispersion and dry powder mixing. All studies included a micrometer-sized TiO(2) control. Exposure to field and artificial soil containing between 200 and 10,000 mg nano-TiO(2) per kilogram of dry soil (mg/kg) had no significant effect (p > 0.05) on juvenile survival and growth, adult earthworm survival, cocoon production, cocoon viability, or total number of juveniles hatched from these cocoons. However, earthworms avoided artificial soils amended with nano-TiO(2) . The lowest concentration at which avoidance was observed was between 1,000 and 5,000 mg nano-TiO(2) per kilogram of soil, depending on the TiO(2) nanomaterial applied. Furthermore, earthworms differentiated between soils amended with 10,000 mg/kg nano-TiO(2) and micrometer-sized TiO(2) . A positive relationship between earthworm avoidance and TiO(2) specific surface area was observed, but the relationship between avoidance and primary particle size was not determined because of the agglomeration and aggregation of nano-TiO(2) materials. Biological mechanisms that may explain earthworm avoidance of nano-TiO(2) are discussed. Results of the present study indicate that earthworms can detect nano-TiO(2) in soil, although exposure has no apparent effect on survival or standard reproductive parameters. PMID:21993953

  9. Can earthworms survive fire retardants?

    USGS Publications Warehouse

    Beyer, W.N.; Olson, A.

    1996-01-01

    Most common fire retardants are foams or are similar to common agricultural fertilizers, such as ammonium sulfate and ammonium phosphate. Although fire retardants are widely applied to soils, we lack basic information about their toxicities to soil organisms. We measured the toxicity of five fire retardants (Firetrol LCG-R, Firetrol GTS-R, Silv-Ex Foam Concentrate, Phos-chek D-75, and Phos-chek WD-881) to earthworms using the pesticide toxicity test developed for earthworms by the European Economic Community. None was lethal at 1,000 ppm in the soil, which was suggested as a relatively high exposure under normal applications. We concluded that the fire retardants tested are relatively nontoxic to soil organisms compared with other environmental chemicals and that they probably do not reduce earthworm populations when applied under usual firefighting conditions.

  10. Unexpected earthworm effects on forest understory plants

    PubMed Central

    2013-01-01

    Background Introduced earthworms are widespread in forests of North America creating significant negative impacts on forest understory communities. However, much of the reported evidence for negative earthworm effects comes from field investigations either comparing invaded and non-invaded forests or across invasion fronts. While important, such work is rarely able to capture the true effect of earthworms on individual plant species because most forests in North America simultaneously face multiple stressors which may confound earthworm impacts. We used a mesocosm experiment to isolate effects of the anecic introduced earthworm, Lumbricus terrestris L. on seedlings of 14 native plant species representing different life form groups (perennial herb, graminoid, and tree). Results Earthworm presence did not affect survival, fertility or biomass of any of the seedling plant species tested over a 17-week period. However, L. terrestris presence significantly decreased growth of two sedges (Carex retroflexa Muhl. ex Willd. and Carex radiata (Wahlenb.) Small) by decreasing the number of culms. Conclusions Our mesocosm results with seedlings contrast with field reports indicating extensive and significant negative effects of introduced earthworms on many mature native forbs, and positive effects on sedges. We suggest that earthworm impacts are context- and age-specific and that generalizations about their impacts are potentially misleading without considering and manipulating other associated factors. PMID:24314263

  11. Earthworm in the 21st century

    NASA Astrophysics Data System (ADS)

    Friberg, Paul; Lisowski, Stefan; Dricker, Ilya; Hellman, Sidney

    2010-05-01

    Earthworm (Johnson et al., 1995) is a fully open-source earthquake data acquisition and processing package that is in widespread use through out the world. Earthworm includes basic seismic data acquistion for the majority of the dataloggers currently available and provides network transport mechanisms and common formats as output for data transferral. In addition, it comes with network seismology tools to compute network detections, perform automated arrival picking, and automated hypocentral and magnitude estimations. More importantly it is an open and free framework in the C-programming language that can be used to create new modules that process waveform and earthquake data in near real time. The number of Earthworm installations is growing annually as are the number of contributions to the system. Furthermore its growth into other areas of waveform data acquistion (namely Geomagnetic observatories and Infrasound arrays) show its adaptability to other waveform technologies and processing strategies. In this presentation we discuss the coming challenges to growing Earthworm and new developments in its use; namely the open source add-ons that have become interfaces to Earthworm's core. These add-ons include GlowWorm, MagWorm, Hydra, SWARM, Winston, EarlyBird, Iworm, and most importantly, AQMS (formerly known as CHEETAH). The AQMS, ANSS Quake Monitoring System, is the Earthworm system created in California which has now been installed in the majority of Regional Seismic Networks (RSNs) in the United States. AQMS allows additional real-time and post-processing of Earthworm generated data to be stored and manipulated in a database using numerous database oriented tools. The use of a relational database for persistence provides users with the ability to implement configuration control and research capabilities not available in earlier Earthworm add-ons. By centralizing on AQMS, the RSNs will be able to leverage new developments by easily sharing Earthworm and AQMS

  12. Teacher's Guide for Earthworms.

    ERIC Educational Resources Information Center

    Bruno, Merle S.; And Others

    This teacher's guide on earthworms includes four major sections: (1) introduction, (2) caring for earthworms in the classroom, (3) classroom activities, and (4) the appendix. The introduction includes information concerning grade level, scheduling, materials, obtaining earthworms, field study, classroom clean-up, and records. Caring for earthworms…

  13. Earthworms and Soil Pollutants

    PubMed Central

    Hirano, Takeshi; Tamae, Kazuyoshi

    2011-01-01

    Although the toxicity of metal contaminated soils has been assessed with various bioassays, more information is needed about the biochemical responses, which may help to elucidate the mechanisms involved in metal toxicity. We previously reported that the earthworm, Eisenia fetida, accumulates cadmium in its seminal vesicles. The bio-accumulative ability of earthworms is well known, and thus the earthworm could be a useful living organism for the bio-monitoring of soil pollution. In this short review, we describe recent studies concerning the relationship between earthworms and soil pollutants, and discuss the possibility of using the earthworm as a bio-monitoring organism for soil pollution. PMID:22247659

  14. Sensitivity of Eisenia andrei (Annelida, Oligochaeta) to a commercial formulation of abamectin in avoidance tests with artificial substrate and natural soil under tropical conditions.

    PubMed

    Nunes, Maria Edna Tenório; Espíndola, Evaldo Luiz Gaeta

    2012-05-01

    Obtaining ecotoxicological data on pesticides in tropical regions is imperative for performing more realistic risk analysis, and avoidance tests have been proposed as a useful, fast and cost-effective tool. Therefore, the present study aimed to evaluate the avoidance behavior of Eisenia andrei to a formulated product, Vertimec® 18 EC (a.i abamectin), in tests performed on a reference tropical artificial soil (TAS), to derive ecotoxicological data on tropical conditions, and a natural soil (NS), simulating crop field conditions. In TAS tests an adaptation of the substrate recommended by OECD and ISO protocols was used, with residues of coconut fiber as a source of organic matter. Concentrations of the pesticide on TAS test ranged from 0 to 7 mg abamectin/kg (dry weight-d.w.). In NS tests, earthworms were exposed to samples of soils sprayed in situ with: 0.9 L of Vertimec® 18 EC/ha (RD); twice as much this dosage (2RD); and distilled water (Control), respectively, and to 2RD: control dilutions (12.5, 25, 50, 75%). All tests were performed under 25 ± 2°C, to simulate tropical conditions, and a 12hL:12hD photoperiod. The organisms avoided contaminated TAS for an EC(50,48h) = 3.918 mg/kg soil d.w., LOEC = 1.75 mg/kg soil d.w. and NOEC = 0.85 mg/kg soil d.w. No significant avoidance response occurred for any NS test. Abamectin concentrations in NS were rather lower than EC(50, 48h) and LOEC determined in TAS tests. The results obtained contribute to overcome a lack of ecotoxicological data on pesticides under tropical conditions, but more tests with different soil invertebrates are needed to improve pesticides risk analysis. PMID:22297724

  15. Approach/avoidance motives, test emotions, and emotional regulation related to testing.

    PubMed

    Schutz, Paul A; Benson, Jeri; Decuir-Gunby, Jessica T

    2008-07-01

    This research stems from our program of work that focuses on understanding how students regulated their emotions related to testing. The primary goal for this study was to incorporate the approach/ avoidance motives into a model of emotional regulation related to testing. In addition, a secondary goal was to report on efforts at construct validation of the scores obtained during the refinement of the Emotional Regulation Related to Testing (ERT) Scale. Our results suggest that underlying beliefs, such as approach/avoid motives and the cognitive-appraisal process, of the ERT had both direct and indirect effects to both pleasant and unpleasant emotions related to testing. In addition, the ERT accounted for 56% of the variance in Pleasant and 87% of Unpleasant Test Emotions. PMID:18612854

  16. Accident Avoidance Skill Training and Performance Testing. Final Report.

    ERIC Educational Resources Information Center

    Hatterick, G. Richard; Barthurst, James R.

    A two-phased study was conducted to determine the feasibility of training drivers to acquire skills needed to avoid critical conflict motor vehicle accidents, and to develop the procedures and materials necessary for such training. Basic data were derived from indepth accident investigations and task analyses of driver behavior. Principal…

  17. Measuring Experiential Avoidance: A Preliminary Test of a Working Model

    ERIC Educational Resources Information Center

    Hayes, Steven C.; Strosahl, Kirk; Wilson, Kelly G.; Bissett, Richard T.; Pistorello, Jacqueline; Toarmino, Dosheen; Polusny, Melissa A.; Dykstra, Thane A.; Batten, Sonja V.; Bergan, John; Stewart, Sherry H.; Zvolensky, Michael J.; Eifert, Georg H.; Bond, Frank W.; Forsyth, John P.; Karekla, Maria; Mccurry, Susan M.

    2004-01-01

    The present study describes the development of a short, general measure of experiential avoidance, based on a specific theoretical approach to this process. A theoretically driven iterative exploratory analysis using structural equation modeling on data from a clinical sample yielded a single factor comprising 9 items. A fully confirmatory factor…

  18. Off to the (Earthworm) Races: A Quick and Flexible Lab Experiment for Introductory Zoology Courses.

    ERIC Educational Resources Information Center

    Switzer, Paul V.; Fritz, Ann H.

    2001-01-01

    Presents a hands-on, investigative lab activity for use in an introductory zoology course. Tests the behavioral hypothesis that substrate texture affects earthworm locomotor ability. Provides background information on earthworm locomotion followed by details of the lab exercise. (NB)

  19. Influence of copper fungicide residues on occurrence of earthworms in avocado orchard soils.

    PubMed

    Van Zwieten, Lukas; Rust, Josh; Kingston, Tim; Merrington, Graham; Morris, Steven

    2004-08-15

    The compost worm Eisenia fetida was used to demonstrate the avoidance by worms of Cu contaminated soil. Soils were collected from two avocado orchards in north eastern New South Wales, Australia. In avoidance trials, worms preferred non-contaminated control soils, sourced from adjacent to the orchard or an OECD control soil, when Cu residues in the orchard soils reached 4-34 mg Cu kg(-1). At levels of 553 mg Cu kg(-1), 90% avoidance of orchard soil was observed. The worms showed preference for the soils in the order; uncontaminated field derived soil >OECD standard soil >Cu contaminated orchard soil. It was demonstrated that OECD standard soil was less favoured by worms than control soil derived from the test sites. While Cu was found to be the primary influence on worm avoidance in orchard soil, other factors, such as elevated soil Zn concentrations, could not be discounted. In a corresponding field study, it was shown that earthworms occurred at lower density in orchard soils with a history of Cu fungicide use. In one such orchard, soil Cu concentrations of up to 270 mg kg(-1) were determined and no earthworms were found, while nearby control sites and less contaminated sites within the orchard had up to 40.7 g m(-2) earthworm biomass. Considering the potential for Cu to accumulate in these soils and the subsequent impacts on soil biota, our results highlight the importance of limiting future application of Cu based fungicides. PMID:15262156

  20. Earthworms lost from pesticides application in potato crops

    NASA Astrophysics Data System (ADS)

    Garcia-Santos, Glenda; Forrer, Karin; Binder, Claudia R.

    2010-05-01

    Bioturbation from earthworm's activity contributes to soil creep and soil carbon dynamics, and provide enough aeration conditions for agricultural practices all over the world. In developing countries where there is a long term misuse of pesticides for agricultural purposes, lost of these benefits from earthworms activity might already yielded negative effects in the current crop production. Little research has been performed on earthworms avoidance to pesticides in developing countries located in the tropics. Furthermore, the complete avoidance reaction (from attraction to 100% avoidance) from earthworms to most of the pesticides used in potato cultivation in developing countries like Colombia is incomplete as yet. Hence the aim of this study is to assess the lost of earthworm on the soils caused by different concentrations of pesticides and associated agricultural impacts caused by a lost in the soil bioturbation. As a first stage, we have studied earthworm's avoidance to pesticide concentration in a potato agricultural area located in Colombia. Local cultivated Eisenia fetida were exposed to four of the most frequent applied active ingredients in potato crops i.e. carbofuran, mancozeb, methamidophos and chlorpyriphos. Adult earthworm toxicity experiments were carried out in two soils, untreated grasslands under standard (ISO guidelines) and undisturbed conditions, and exposed to six different concentrations of the active ingredients. The results of the avoidance reaction on the standard soils were significant for carbofuran, mancoceb and chlorpyrifos. For each of the three active ingredients, we found i) overuse of pesticide, ii) applied dose of carbofuran, mancoceb and chlorpyrifos by the farmers potentially caused 20%, 11% and 9% of earthworms avoidance on the cultivated soils, respectively.

  1. Implementation and testing of a real-time 3-component phase picking program for Earthworm using the CECM algorithm

    NASA Astrophysics Data System (ADS)

    Baker, B. I.; Friberg, P. A.

    2014-12-01

    Modern seismic networks typically deploy three component (3C) sensors, but still fail to utilize all of the information available in the seismograms when performing automated phase picking for real-time event location. In most cases a variation on a short term over long term average threshold detector is used for picking and then an association program is used to assign phase types to the picks. However, the 3C waveforms from an earthquake contain an abundance of information related to the P and S phases in both their polarization and energy partitioning. An approach that has been overlooked and has demonstrated encouraging results is the Component Energy Comparison Method (CECM) by Nagano et al. as published in Geophysics 1989. CECM is well suited to being used in real-time because the calculation is not computationally intensive. Furthermore, the CECM method has fewer tuning variables (3) than traditional pickers in Earthworm such as the Rex Allen algorithm (N=18) or even the Anthony Lomax Filter Picker module (N=5). In addition to computing the CECM detector we study the detector sensitivity by rotating the signal into principle components as well as estimating the P phase onset from a curvature function describing the CECM as opposed to the CECM itself. We present our results implementing this algorithm in a real-time module for Earthworm and show the improved phase picks as compared to the traditional single component pickers using Earthworm.

  2. EARTHWORMS AS ECOTOXICOLOGICAL ASSESSMENT TOOLS

    EPA Science Inventory

    Increased interest for earthworm research and the need for soil assessment methods has encouraged the use of earthworms as assessment organisms. Earthworms exhibit many advantages for use in assessing the impact of toxic and hazardous materials on soil systems. Earthworms are kno...

  3. Darwin, Earthworms & Circadian Rhythms: A Fertile Field for Science Fair Experiments

    ERIC Educational Resources Information Center

    Burns, John T.; Scurti, Paul J.; Furda, Amy M.

    2009-01-01

    This article discusses why the study of earthworms has fascinated many scientists, and why earthworms make ideal experimental animals for students to test in the laboratory. Although earthworms may appear to be primitive, they are governed by both circadian and seasonal rhythms, just as more advanced organisms are. They possess an intelligence…

  4. Acute toxicity testing of chemicals-Opportunities to avoid redundant testing and use alternative approaches.

    PubMed

    Creton, Stuart; Dewhurst, Ian C; Earl, Lesley K; Gehen, Sean C; Guest, Robert L; Hotchkiss, Jon A; Indans, Ian; Woolhiser, Michael R; Billington, Richard

    2010-01-01

    Assessment of the acute systemic oral, dermal, and inhalation toxicities, skin and eye irritancy, and skin sensitisation potential of chemicals is required under regulatory schemes worldwide. In vivo studies conducted to assess these endpoints can sometimes be associated with substantial adverse effects in the test animals, and their use should always be scientifically justified. It has been argued that while information obtained from such acute tests provides data needed to meet classification and labelling regulations, it is of limited value for hazard and risk assessments. Inconsistent application of in vitro replacements, protocol requirements across regions, and bridging principles also contribute to unnecessary and redundant animal testing. Assessment of data from acute oral and dermal toxicity testing demonstrates that acute dermal testing rarely provides value for hazard assessment purposes when an acute oral study has been conducted. Options to waive requirements for acute oral and inhalation toxicity testing should be employed to avoid unnecessary in vivo studies. In vitro irritation models should receive wider adoption and be used to meet regulatory needs. Global requirements for sensitisation testing need continued harmonisation for both substance and mixture assessments. This paper highlights where alternative approaches or elimination of tests can reduce and refine animal use for acute toxicity requirements. PMID:20144136

  5. Young Men's Aggressive Tactics to Avoid Condom Use: A Test of a Theoretical Model

    ERIC Educational Resources Information Center

    Davis, Kelly Cue; Logan-Greene, Patricia

    2012-01-01

    Although research has demonstrated that men's aggression against women and inconsistent condom use are related phenomena, little is known about what factors increase risk for aggression to avoid condom use. The present article tests a theory-based model of condom avoidance through use of sexual aggression. Adult male participants (N = 289) were…

  6. Influence of feeding and earthworm density on compound bioaccumulation in earthworms Eisenia andrei.

    PubMed

    Šmídová, Klára; Šerá, Jana; Bielská, Lucie; Hofman, Jakub

    2015-12-01

    Earthworm density and feeding during exposure to contaminated soil have been used inconsistently in bioaccumulation studies, which may lead to possible errors in risk assessment and modeling. Hydrophobic organic pollutants with a wide range of environmental properties (phenanthrene, pyrene, lindane, p,p'-DDT, and PCB 153) were used to study the effect of different earthworm densities in combination with the presence or absence of feeding on bioaccumulation factors (BAFs). Similar BAFs were found at various soil-to-worm ratios, with the exception of phenanthrene. We recommend using at least 15 gsoil dw per earthworm. The absence of feeding doubled the BAFs and, thus, using no food ration can be considered as "the worst case scenario". Whenever food is to be applied (i.e. to ensure the validity of the test in earthworm mass loss), we suggest feeding depending on the organic carbon content of the studied soil. PMID:26378968

  7. Effects of metals on earthworm life cycles: a review.

    PubMed

    Sivakumar, S

    2015-08-01

    Earthworms are abundant and ecologically very important organisms in the soil ecosystem. Impacts by pollutants on earthworm communities greatly influence the fertility of the terrestrial environment. In ecotoxicology, earthworms are good indicators of metal pollution. The observed median lethal concentrations (LC50) and the effective concentrations that cause 50% reduction of earthworm growth and reproduction (EC50) are referred to as toxicity concentrations or endpoints. In addition, the 'no observed effective concentration' (NOEC) is the estimation of the toxicity of metals on earthworms expressed as the highest concentration tested that does not show effects on growth and reproduction compared to controls. This article reviews the ecotoxicological parameters of LC50, EC50 and NOEC of a set of worms exposed to a number of metals in various tested media. In addition, this article reviews metal accumulation and the influences of soil characteristics on metal accumulation in earthworms. Morphological and behavioural responses are often used in earthworm toxicity studies. Therefore, earthworm responses due to metal toxicity are also discussed in this article. PMID:26215824

  8. Earthworm Effects without Earthworms: Inoculation of Raw Organic Matter with Worm-Worked Substrates Alters Microbial Community Functioning

    PubMed Central

    Aira, Manuel; Domínguez, Jorge

    2011-01-01

    Background Earthworms are key organisms in organic matter decomposition because of the interactions they establish with soil microorganisms. They enhance decomposition rates through the joint action of direct effects (i.e. effects due to direct earthworm activity such as digestion, burrowing, etc) and indirect effects (i.e. effects derived from earthworm activities such as cast ageing). Here we test whether indirect earthworm effects affect microbial community functioning in the substrate, as when earthworms are present (i. e., direct effects). Methodology/Principal Findings To address these questions we inoculated fresh organic matter (pig manure) with worm-worked substrates (vermicompost) produced by three different earthworm species. Two doses of each vermicompost were used (2.5 and 10%). We hypothesized that the presence of worm-worked material in the fresh organic matter will result in an inoculum of different microorganisms and nutrients. This inoculum should interact with microbial communities in fresh organic matter, thus promoting modifications similar to those found when earthworms are present. Inoculation of worm-worked substrates provoked significant increases in microbial biomass and enzyme activities (β-glucosidase, cellulase, phosphatase and protease). These indirect effects were similar to, although lower than, those obtained in pig manure with earthworms (direct and indirect earthworm effects). In general, the effects were not dose-dependent, suggesting the existence of a threshold at which they were triggered. Conclusion/Significance Our data reveal that the relationships between earthworms and microorganisms are far from being understood, and suggest the existence of several positive feedbacks during earthworm activity as a result of the interactions between direct and indirect effects, since their combination produces stronger modifications to microbial biomass and enzyme activity. PMID:21298016

  9. Nutrition Studies with Earthworms.

    ERIC Educational Resources Information Center

    Tobaga, Leandro

    1980-01-01

    Describes experiments which demonstrate how different diets affect the growth rate of earthworms. Procedures for feeding baby worms are outlined, the analysis of results are discussed, and various modifications of the exercise are provided. (CS)

  10. Portable conduction velocity experiments using earthworms for the college and high school neuroscience teaching laboratory.

    PubMed

    Shannon, Kyle M; Gage, Gregory J; Jankovic, Aleksandra; Wilson, W Jeffrey; Marzullo, Timothy C

    2014-03-01

    The earthworm is ideal for studying action potential conduction velocity in a classroom setting, as its simple linear anatomy allows easy axon length measurements and the worm's sparse coding allows single action potentials to be easily identified. The earthworm has two giant fiber systems (lateral and medial) with different conduction velocities that can be easily measured by manipulating electrode placement and the tactile stimulus. Here, we present a portable and robust experimental setup that allows students to perform conduction velocity measurements within a 30-min to 1-h laboratory session. Our improvement over this well-known preparation is the combination of behaviorally relevant tactile stimuli (avoiding electrical stimulation) with the invention of minimal, low-cost, and portable equipment. We tested these experiments during workshops in both a high school and college classroom environment and found positive learning outcomes when we compared pre- and posttests taken by the students. PMID:24585472

  11. Disposal of dredged sediments in tropical soils: ecotoxicological effects on earthworms.

    PubMed

    Cesar, Ricardo; Natal-da-Luz, Tiago; Sousa, José Paulo; Colonese, Juan; Bidone, Edison; Castilhos, Zuleica; Egler, Silvia; Polivanov, Helena

    2014-03-01

    The upper limit concentrations of metals established by international legislations for dredged sediment disposal and soil quality do not take into consideration the properties of tropical soils (generally submitted to more intense weathering processes) on metal availability and ecotoxicity. Aiming to perform an evaluation on the suitability of these threshold values in tropical regions, the ecotoxicity of metal-contaminated dredged sediment from the Guanabara Bay (Rio de Janeiro, Brazil) was investigated. Acute and avoidance tests with Eisenia andrei were performed with mixtures of dredged sediment with a ferralsol (0.00, 6.66, 13.12, 19.98, and 33.30 %) and a chernosol (0.00, 6.58, 13.16, 19.74, and 32.90 %). Mercury, lead, nickel, chromium, copper, and zinc concentrations were measured in test mixtures and in tissues of surviving earthworms from the acute tests. While ferralsol test mixtures provoked significant earthworm avoidance response at concentrations ≥13.31 %, the chernosol mixtures showed significant avoidance behavior only at the 19.74 % concentration. The acute tests showed higher toxicity in ferralsol mixtures (LC50 = 9.9 %) compared to chernosol mixtures (LC50 = 16.5 %), and biomass increased at the lowest sediment doses in treatments of both test soils. Most probably, the expansive clay minerals present in chernosol contributed to reduce metal availability in chernosol mixtures, and consequently, the ecotoxicity of these treatments. The bioconcentration factors (BCF) for zinc and copper were lower with increasing concentrations of the dredged sediment, indicating the existence of internal regulating processes. Although the BCF for mercury also decreased with the increasing test concentrations, the known no biological function of this metal in the earthworms metabolism lead to suppose that Hg measured was not present in bioaccumulable forms. BCFs estimated for the other metals were generally higher in the highest dredged sediment doses

  12. Earthworms, as ecosystem engineers, influence multiple aspects of a salamander's ecology.

    PubMed

    Ransom, Tami S

    2011-03-01

    Ecosystem engineers create habitat that can be used by other species in multiple ways, such as refugees from predators, places to breed, or areas with increased prey resources. I conducted a series of enclosure experiments to: (1) determine if salamanders use earthworm burrows, and (2) examine the potential influence of earthworm burrow use and indirect effects on salamander intra- and interspecific competition, predator avoidance, and seasonal performance. I found that one species of woodland salamander, Plethodon cinereus, used earthworm burrows 50% of the time when burrows were present. Neither adults nor juveniles of the congeneric P. glutinosus used earthworm burrows. Intraspecific, but not interspecific, competition by P. cinereus affected salamander behavior when earthworms were absent, with P. cinereus found under cover objects >70% of the time when alone or with a P. glutinosus, but only 40% of the time when with another P. cinereus. When earthworms were present, the behavior of P. cinereus was similar across salamander treatments. Earthworms decreased the amount of leaf litter and microinvertebrates, although this did not affect salamander mass. In subsequent experiments using only P. cinereus, the refuge provided by earthworm burrows increased the survival of P. cinereus over the winter and allowed P. cinereus to avoid being consumed by the common garter snake (Thamnophis sirtalis). Because earthworm burrows provide a refuge for P. cinereus during intraspecific encounters, in the presence of a predator and over the winter, they may serve as an important belowground-aboveground linkage in eastern forests where salamanders are common. PMID:20848134

  13. Buffering the responses of avoidantly attached romantic partners in strain test situations.

    PubMed

    Farrell, Allison K; Simpson, Jeffry A; Overall, Nickola C; Shallcross, Sandra L

    2016-08-01

    Strain tests are unique contexts that have important implications for relationships, but they have rarely been studied in social interactions. We investigate how more avoidant individuals (responders) react when their romantic partners (askers) request cooperation with an important plan/goal that requires a major sacrifice from responders. As predicted, more avoidant responders were less accommodating when asked to sacrifice and showed drops in trust and commitment following the strain test discussion. However, certain asker behaviors-expressing confidence that the responding partner will facilitate the request, and acknowledging their sacrifices in doing so-led more avoidant responders to react more positively during and after the strain test discussions. Showing responsiveness, another positive asker behavior, promoted growth in trust and commitment, but it did not help more avoidant responders react more positively to the asker's goal. Blending key principles of interdependence and attachment theory, this is the first behavioral observation study to identify the specific partner behaviors that help highly avoidant people respond constructively in strain test situations and to suggest how avoidant partners can become more trusting and committed in their romantic relationships. (PsycINFO Database Record PMID:26914433

  14. Native and exotic earthworms affect orchid seed loss

    PubMed Central

    McCormick, Melissa K.; Parker, Kenneth L.; Szlavecz, Katalin; Whigham, Dennis F.

    2013-01-01

    Non-native earthworms have invaded ecosystems around the world but have recently received increased attention as they invaded previously earthworm-free habitats in northern North America. Earthworms can affect plants by ingesting seeds and burying them in the soil. These effects can be negative or positive but are expected to become increasingly negative with decreasing seed size. Orchids have some of the smallest seeds of any plants, so we hypothesized that earthworm consumption of seeds would decrease seed viability and lead to burial of ingested seeds. We used a combination of mesocosms and field measurements to determine whether native and non-native earthworms would affect Goodyera pubescens seed germination by decreasing seed viability through digestion or burial. To determine soil depths at which seed burial would decrease chances of germination, we used field measurements of the abundance of mycorrhizal fungi needed for G. pubescens germination at different soil depths. We found that the combined effects of earthworm ingestion and burial would be expected to result in a loss of 49 % of orchid seeds in mature forests and 68 % of those in successional forests over an average year. Differences in seed ingestion and burial among soils from mature and successional forests were probably driven by differences in their ability to support earthworm biomass and not by differences in earthworm behaviour as a function of soil type. The combined effects of earthworm ingestion and burial have the potential to result in substantial loss of orchid seeds, particularly in successional forests. This effect may slow the ability of orchids to recolonize forests as they proceed through succession. Determining whether this strong effect of earthworms on G. pubescens viability and germination also applies to other orchid species awaits further testing.

  15. The evaluation of the activity of medicinal remedies of plant and animal origin on the regeneration of the earthworms' tail segments.

    PubMed

    Bybin, Viktor Alexandrovich; Stom, Daevard Iosifovich

    2014-01-01

    Now, in the global community there is enough hard recommendation to replace the vertebrate test animals into simpler organisms at the development, testing, and evaluation of the quality pharmaceuticals. The feature of planarian to regenerate in new individual planarian from a piece, which is only 1/7 of the original animal, allowed to create the alternative methods of testing of drugs, dietary supplements, water quality, influence of electromagnetic fields, and other radiations. The tests on planarian can replace the ones that are held today on mammals. However, the lacks of the bioassays based on the planarian regeneration are the need for complex and expensive video equipment for recording the regrowth of worms' body, the difficulties of culturing of flatworms and fairly long period of response. These difficulties can be avoided by using another group of the worms of type Annelida. The new individual can be fully recovered only from the front half of the body in many species of earthworms. Thus, the influence of the pharmaceuticals from earthworms, mummy, and Orthilia secunda on the ability of earthworms to regenerate lost tail segments has been investigated. The relations of the activity of preparations tested with doses and the time of the storage have been revealed. The principal possibility of applicability of the test reaction studied as a way to evaluate the effects and quality of remedies based on medicinal plants and earthworms has been shown. PMID:26692755

  16. Approach, avoidance and weight-related testing: An investigation of frontal EEG asymmetry.

    PubMed

    Faries, Mark D; Kephart, Wesley; Jones, Eric J

    2015-01-01

    Two motivational systems underlie behaviour and affective responses - an inhibition/avoidance system and an activation/approach system. The purpose of the present study was to explore if individual differences in these motivational systems would occur in response to common weight and body composition testing within a sample of young, adult women. Electroencephalogram was used to distinguish approach or avoidance orientations via frontal asymmetry before and after testing sessions. Clear distinctions in motivational response were found, with 65% of the sample responding with an approach motivation, while 35% responded with an avoidance motivation. Even though all participants, on average, experienced a negative affective response, only the avoidance group self-reported a subsequent increase in "comfort food" consumption of desserts and snacks the week following the testing session. As shown with other stressors, clear individual differences exist in motivational responses to common weight and body composition testing. Such testing produces a general negative affective response; however, the individual differences in motivational responses might produce different behavioural choices. Future research and interventions in health communication should be considerate to this variation in motivational responses to help explain changes in both healthy and unhealthy behaviours following interactions involving one's body weight and/or body composition. PMID:25220609

  17. Young Men's Aggressive Tactics to Avoid Condom Use: A Test of a Theoretical Model

    PubMed Central

    Davis, Kelly Cue; Logan-Greene, Patricia

    2012-01-01

    Although research has demonstrated that men's aggression against women and inconsistent condom use are related phenomena, little is known about what factors increase risk for aggression to avoid condom use. The present article tests a theory-based model of condom avoidance through use of sexual aggression. Adult male participants (N = 289) were recruited nationally through online advertisements. Aggressive tactics to avoid condom use were measured using an adapted version of the revised Sexual Experiences Survey, and a variety of aggressive behaviors spanning coercion to physical force were assessed. One hundred participants (35.3%) reported at least one instance of coercion or aggression to avoid using a condom. Structural equation modeling indicated that attitudes toward women, inconsistent condom use, and number of sexual partners were significant predictors of aggressive tactics to avoid condom use. A better understanding of the attitudinal and behavioral pathways through which men avoid condom use through aggressive and coercive means will ultimately result in improved education and prevention efforts for at-risk men and women. PMID:23139623

  18. Fighting Testing ACAT/FRRP: Automatic Collision Avoidance Technology/Fighter Risk Reduction Project

    NASA Technical Reports Server (NTRS)

    Skoog, Mark A.

    2009-01-01

    This slide presentation reviews the work of the Flight testing Automatic Collision Avoidance Technology/Fighter Risk Reduction Project (ACAT/FRRP). The goal of this project is to develop common modular architecture for all aircraft, and to enable the transition of technology from research to production as soon as possible to begin to reduce the rate of mishaps. The automated Ground Collision Avoidance System (GCAS) system is designed to prevent collision with the ground, by avionics that project the future trajectory over digital terrain, and request an evasion maneuver at the last instance. The flight controls are capable of automatically performing a recovery. The collision avoidance is described in the presentation. Also included in the presentation is a description of the flight test.

  19. Odor-cued taste avoidance: a simple and robust test of mouse olfaction.

    PubMed

    Slotnick, Burton; Coppola, David M

    2015-05-01

    In odor-cued taste avoidance (OCTA), thirsty mice, offered either an odorized nonaversive fluid (S+) or an odorized aversive fluid (S-), quickly learn to use odor to avoid drinking the S-. Acquisition of both odor detection and odor discrimination tasks is very rapid with learning evidenced in most cases by either long response times or total avoidance on the second presentation of the S- stimulus. OCTA is perhaps one of the simplest conditioning procedures for assessing olfaction in mice; it requires only a test box, drinkometer circuit, and thirsty mice accustomed to drinking in the apparatus. Its advantages over the most commonly used alternatives, habituation-dishabituation, and the mouse dig test, are discussed. PMID:25787943

  20. Simulation and Flight Test Capability for Testing Prototype Sense and Avoid System Elements

    NASA Technical Reports Server (NTRS)

    Howell, Charles T.; Stock, Todd M.; Verstynen, Harry A.; Wehner, Paul J.

    2012-01-01

    NASA Langley Research Center (LaRC) and The MITRE Corporation (MITRE) have developed, and successfully demonstrated, an integrated simulation-to-flight capability for evaluating sense and avoid (SAA) system elements. This integrated capability consists of a MITRE developed fast-time computer simulation for evaluating SAA algorithms, and a NASA LaRC surrogate unmanned aircraft system (UAS) equipped to support hardware and software in-the-loop evaluation of SAA system elements (e.g., algorithms, sensors, architecture, communications, autonomous systems), concepts, and procedures. The fast-time computer simulation subjects algorithms to simulated flight encounters/ conditions and generates a fitness report that records strengths, weaknesses, and overall performance. Reviewed algorithms (and their fitness report) are then transferred to NASA LaRC where additional (joint) airworthiness evaluations are performed on the candidate SAA system-element configurations, concepts, and/or procedures of interest; software and hardware components are integrated into the Surrogate UAS research systems; and flight safety and mission planning activities are completed. Onboard the Surrogate UAS, candidate SAA system element configurations, concepts, and/or procedures are subjected to flight evaluations and in-flight performance is monitored. The Surrogate UAS, which can be controlled remotely via generic Ground Station uplink or automatically via onboard systems, operates with a NASA Safety Pilot/Pilot in Command onboard to permit safe operations in mixed airspace with manned aircraft. An end-to-end demonstration of a typical application of the capability was performed in non-exclusionary airspace in October 2011; additional research, development, flight testing, and evaluation efforts using this integrated capability are planned throughout fiscal year 2012 and 2013.

  1. Cooperative Collision Avoidance Step 1 - Technology Demonstration Flight Test Report. Revision 1

    NASA Technical Reports Server (NTRS)

    Trongale, Nicholas A.

    2006-01-01

    The National Aeronautics and Space Administration (NASA) Access 5 Project Office sponsored a cooperative collision avoidance flight demonstration program for unmanned aircraft systems (UAS). This flight test was accomplished between September 21st and September 27th 2005 from the Mojave Airport, Mojave, California. The objective of these flights was to collect data for the Access 5 Cooperative Collision Avoidance (CCA) Work Package simulation effort, i.e., to gather data under select conditions to allow validation of the CCA simulation. Subsequent simulation to be verified were: Demonstrate the ability to detect cooperative traffic and provide situational awareness to the ROA pilot; Demonstrate the ability to track the detected cooperative traffic and provide position information to the ROA pilot; Demonstrate the ability to determine collision potential with detected cooperative traffic and provide notification to the ROA pilot; Demonstrate that the CCA subsystem provides information in sufficient time for the ROA pilot to initiate an evasive maneuver to avoid collision; Demonstrate an evasive maneuver that avoids collision with the threat aircraft; and lastly, Demonstrate the ability to assess the adequacy of the maneuver and determine that the collision potential has been avoided. The Scaled Composites, LLC Proteus Optionally Piloted Vehicle (OPV) was chosen as the test platform. Proteus was manned by two on-board pilots but was also capable of being controlled from an Air Vehicle Control Station (AVCS) located on the ground. For this demonstration, Proteus was equipped with cooperative collision sensors and the required hardware and software to place the data on the downlink. Prior to the flight phase, a detailed set of flight test scenarios were developed to address the flight test objectives. Two cooperative collision avoidance sensors were utilized for detecting aircraft in the evaluation: Traffic Alert and Collision Avoidance System-II (TCAS-II) and

  2. Running Wheel for Earthworms.

    PubMed

    Wilson, W Jeffrey; Johnson, Brandon A

    2016-01-01

    We describe the construction and use of a running wheel responsive to the movement of the earthworm. The wheel employs readily available, inexpensive components and is easily constructed. Movement of the wheel can be monitored visually or via standard behavioral laboratory computer interfaces. Examples of data are presented, and possibilities for use in the teaching classroom are discussed. PMID:27385934

  3. Structure and earthworms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Earthworms are an important part of the soil ecosystem and an indicator of soil quality. Sometimes referred to as ecosystem engineers, they play a pivotal role in maintaining soil productivity. Their burrowing, feeding, and casting activities alter the physical, chemical, and biological properties o...

  4. Running Wheel for Earthworms

    PubMed Central

    Wilson, W. Jeffrey; Johnson, Brandon A.

    2016-01-01

    We describe the construction and use of a running wheel responsive to the movement of the earthworm. The wheel employs readily available, inexpensive components and is easily constructed. Movement of the wheel can be monitored visually or via standard behavioral laboratory computer interfaces. Examples of data are presented, and possibilities for use in the teaching classroom are discussed. PMID:27385934

  5. Strategies for avoiding errors and ambiguities in the analysis of oscillatory pumping tests

    NASA Astrophysics Data System (ADS)

    Cardiff, Michael; Sayler, Claire

    2016-09-01

    Oscillatory pumping tests have recently seen a resurgence in interest as a strategy for aquifer characterization. In a cross-well pumping test, measured responses to oscillatory pumping tests consist of the amplitude and phase delay of pressure changes at an observation well. This information can be used to obtain estimates of effective aquifer parameters (conductivity and storage coefficients), by fitting field data with an analytical model through parameter estimation. Alternately, multiple pumping tests can be fit simultaneously through tomographic analyses. However, in both cases, analysis of obtained test results may be ambiguous if "phase wrapping" occurs, i.e. if signals are delayed by more than one period. In this work, we demonstrate scenarios under which phase wrapping can make analysis of oscillatory testing difficult, and present guidelines for avoiding ambiguity in oscillatory testing results.

  6. Small UAV Automatic Ground Collision Avoidance System Design Considerations and Flight Test Results

    NASA Technical Reports Server (NTRS)

    Sorokowski, Paul; Skoog, Mark; Burrows, Scott; Thomas, SaraKatie

    2015-01-01

    The National Aeronautics and Space Administration (NASA) Armstrong Flight Research Center Small Unmanned Aerial Vehicle (SUAV) Automatic Ground Collision Avoidance System (Auto GCAS) project demonstrated several important collision avoidance technologies. First, the SUAV Auto GCAS design included capabilities to take advantage of terrain avoidance maneuvers flying turns to either side as well as straight over terrain. Second, the design also included innovative digital elevation model (DEM) scanning methods. The combination of multi-trajectory options and new scanning methods demonstrated the ability to reduce the nuisance potential of the SUAV while maintaining robust terrain avoidance. Third, the Auto GCAS algorithms were hosted on the processor inside a smartphone, providing a lightweight hardware configuration for use in either the ground control station or on board the test aircraft. Finally, compression of DEM data for the entire Earth and successful hosting of that data on the smartphone was demonstrated. The SUAV Auto GCAS project demonstrated that together these methods and technologies have the potential to dramatically reduce the number of controlled flight into terrain mishaps across a wide range of aviation platforms with similar capabilities including UAVs, general aviation aircraft, helicopters, and model aircraft.

  7. Comparison of heavy-metal uptake by Eisenia foetida with that of other common earthworms. Final technical report

    SciTech Connect

    Stafford, E.A.; Edwards, C.A.

    1986-01-01

    Earthworms have been used in the field to indicate levels of soil pollution and in the laboratory for the ecotoxicological testing of industrial chemicals. An earthworm bioassay procedure developed at the Waterways Experiment Station (Vicksburg, Mississippi) was modified and evaluated as a method of providing information on heavy-metal bioavailability in contaminated soils and sediments from Europe. Eight soils/sediments containing elevated levels of a least one of the elements Zn, Cu, Cd and Pb were selected as well as a control and a reference soil. Six species of earthworm, including the WES bioassay earthworm E. foetida, and five field species were grown in the soils/sediments for periods of 15, 28 or 56 days. Concentrations of the elements Zn, Cu, Cd, Ni, Cr and Pb present in the earthworm samples (corrected for the presence of soil-derived metals within the earthworm gut) were compared between earthworm species from the same soil and for each earthworm species from a range of metal contaminated soils/sediments. A close linear relationship between metal uptake by E.foetida and the field species of earthworm emerged and good correlation between total (HNO3/HC104) soil Pb and Cd levels and earthworm tissue concentrations and between DTPA extractable soil Cu and Cc levels and earthworm tissue concentrations was observed.

  8. Interaction of plant and earthworm during primary succession in heaps after coal

    NASA Astrophysics Data System (ADS)

    Roubíčková, Alena; Frouz, Jan

    2015-04-01

    These results of field manipulation experiment show that earthworms can remarkably influence vegetation succession on spoil heaps, namely promoting grasses and late succession species. This is in agreement with concurrent appearance of earthworms and some plant species typical for late-succession communities of meadows and forests aren't purely coincidental. On the other hand, facilitation of soil conditions by plant communities during succession is an important factor in earthworm distribution on the spoil heaps; earthworms showed a low survival on sites with sparse vegetation cover and thin litter layer, which means that their occurrence in certain stages of succession isn't determined only by migration abilities or passive dispersal. More field experiments are needed to test if earthworms could be used in directed succession management practices to speed up the natural rate of succession. Preliminary results from an experiment with introduction earthworms to a 20- year old, earthworm-free site indicate that colonization of this site from a single deposition of about 100 specimen of epigeic and 100 endogeic earthworms is slow and not very efficient. Results show that interaction between earthworm and vegetation are important in ecosystem development in post mining sites.

  9. Flight test of a low-altitude helicopter guidance system with obstacle avoidance capability

    NASA Technical Reports Server (NTRS)

    Zelenka, Richard E.; Clark, Raymond F.; Branigan, Robert G.

    1995-01-01

    Military aircraft regularly conduct missions that include low-atltitude, near-terrain flight in order to increase covertness and payload effectiveness. Civilian applications include airborne fire fighting, police surveillance, search and rescue, and helicopter emergency medical service. Several fixed-wing aircraft now employ terrain elevation maps and forward-pointed radars to achieve automated terrain following or terrain avoidance flight. Similar systems specialized to helicopters and their flight regime have not received as much attention. A helicopter guidance system relying on digitized terrain elevation maps has been developed that employs airborne navigation, mission requirements, aircraft performance limits, and radar altimeter returns to generate a valley-seeking, low-altitude trajectory between waypoints. The guidance trajectory is symbolically presented to the pilot on a helmet mounted display. This system has been flight tested to 150 ft (45.7 m) above ground level altitude at 80 kts, and is primarily limited by the ability of the pilot to perform manual detection and avoidance of unmapped hazards. In this study, a wide field of view laser radar sensor has been incorporated into this guidance system to assist the pilot in obstacle detection and avoidance, while expanding the system's operational flight envelope. The results from early flight tests of this system are presented. Low-altitude missions to 100 ft (30.5 m) altitude at 80n kts in the presence of unmapped natural and man-made obstacles were demonstrated while the pilot maintained situational awareness and tracking of the guidance trajectory. Further reductions in altitude are expected with continued flight testing.

  10. Initial test of an emotional avoidance model of restriction in anorexia nervosa using ecological momentary assessment.

    PubMed

    Haynos, Ann F; Crosby, Ross D; Engel, Scott G; Lavender, Jason M; Wonderlich, Stephen A; Mitchell, James E; Peterson, Carol B; Crow, Scott J; Le Grange, Daniel

    2015-09-01

    It has been hypothesized that restrictive eating allows individuals with anorexia nervosa (AN) to avoid contact with negative emotions; however, this presumption has not been directly tested. In this study, we conducted an initial investigation examining whether restrictive eating serves an emotional avoidance function among individuals with AN. Females with AN (n = 118) reported on negative and positive affect, anxiety/tension, and eating behaviors at multiple time points daily over a 2-week period using ecological momentary assessment methodology. Affective patterns were compared using generalized estimating equation models between days in which participants reported either: (1) relatively high restriction (without binge eating); (2) relatively low restriction (without binge eating); (3) binge eating; or (4) no restriction or binge eating. We hypothesized that, if restriction were functioning to avoid negative affect, average negative affect and anxiety/tension, as well as average negative and positive affect lability, would be lower and average positive affect would be higher on days characterized by high levels of restriction compared to other eating patterns. Contrary to hypotheses: (1) average negative affect, anxiety/tension, and positive affect were not significantly different between days characterized by high restriction and those characterized by low or no restriction; (2) Negative affect and anxiety/tension lability were higher on days characterized by high restriction compared to no restriction or binge eating days; (3) Anxiety/tension lability was higher on days characterized by high versus low levels of restriction. This patterns of findings does not support an avoidance model of restrictive eating for individuals with AN. PMID:26228412

  11. The use of multiple-choice tests in anatomy: common pitfalls and how to avoid them.

    PubMed

    Vahalia, K V; Subramaniam, K; Marks, S C; De Souza, E J

    1995-01-01

    Multiple-choice questions (MCQ) are widely used to evaluate students in the health sciences, including anatomy. Unusual responses in 90 simple MCQ examinations have been identified and classified as to cause, including a number of illustrated examples. About one-quarter of these errors were attributable to the teacher and could have been avoided by a critical analysis of the questions before use. The increasing use of sophisticated formats of the MCQ in medical education indicates that teachers need to analyze their questions more carefully before and after actual tests to minimize errors. PMID:7697515

  12. Prey choice by carabid beetles feeding on an earthworm community analysed using species- and lineage-specific PCR primers.

    PubMed

    King, R Andrew; Vaughan, Ian P; Bell, James R; Bohan, David A; Symondson, William O C

    2010-04-01

    The carabid beetle Pterostichus melanarius is a major natural enemy of pests, such as aphids and slugs in agricultural systems. Earthworms are a dominant non-pest component of the diet of P. melanarius which help sustain the beetles during periods when the pest population is low or absent. In this study we wanted to test whether this predator exercises prey choice among different earthworm species or ecological groups. High levels of genetic diversity within morphological species of earthworm necessitated the development of primers that were specific not just to species but lineages and sub-lineages within species as well. Gut samples from beetles were analysed using multiplex-PCR and fluorescent-labelled primers. Calibratory feeding trials were undertaken to calculate median detection times for prey DNA following ingestion. Extensive testing demonstrated that the primers were species-specific, that detection periods were negatively related to amplicon size and that meal size had a highly significant effect on detection periods. Monte Carlo simulations showed that, in general, worms were being predated in proportion to their densities in the field with little evidence of prey choice, other than probable avoidance of the larger, deep-living species. There was no evidence that epigeic species were being taken preferentially in comparison with endogeic species. There was also no evidence that defensive secretions by Allolobophora chlorotica reduced predation pressure on this species by P. melanarius. We concluded that any management system that increases earthworm densities generally, regardless of component species, is likely to be optimal for increasing numbers of this beneficial beetle predator. PMID:20345680

  13. Anxiolytic effects of nicotine in a rodent test of approach-avoidance conflict

    PubMed Central

    Cohen, Ami; Young, Robert W.; Velazquez, Miguel; Groysman, Mariya; Noorbehesht, Kavon; Ben-Shahar, Osnat; Ettenberg, Aaron

    2010-01-01

    RATIONALE Nicotine has been reported to produce both anxiolytic and/or anxiogenic effects in humans and animals. OBJECTIVES This study examined whether pretreatment with nicotine would alter anxiety in a unique runway model of approach-avoidance conflict. MATERIALS AND METHODS Food-restricted rats were trained to run a straight alley once a day to obtain food upon goal-box entry. Beginning on trial 11, food reward was followed by a series of 5 foot-shocks (0.3–0.4 mA, 0.5 sec) in the goal-box. Non-shocked control rats continued to run for food only. The resulting association of the goal-box with both a positive (food) and negative (foot-shock) stimulus produced an approach-avoidance conflict (subjects exhibited “retreat behaviors” in which they would approach the goal-box, stop and then retreat back towards the start-box). Once retreats were established, their sensitivity to nicotine pretreatment (0.0, 0.03, 0.045, 0.06 or 0.075 mg/kg i.v.) was compared to saline. In subsequent tests, the effects of nicotine (0.06 or 0.03 mg/kg) were examined on spontaneous activity (locomotion) and center-square entries in an open field (anxiety). RESULTS 0.06 and 0.075 mg/kg, but not lower doses of nicotine, reduced the number of runway retreats and 0.06 mg/kg nicotine increased the number of open-field center entries relative to saline. No effects on locomotion were observed. CONCLUSIONS Nicotine reduced approach-avoidance conflict and increased the rats’ willingness to enter the center of an open field suggesting that the drug can produce anxiolytic properties, and that such effects may serve as an important factor in the persistence of smoking behavior. PMID:19241061

  14. Non-native earthworms promote plant invasion by ingesting seeds and modifying soil properties

    NASA Astrophysics Data System (ADS)

    Clause, Julia; Forey, Estelle; Lortie, Christopher J.; Lambert, Adam M.; Barot, Sébastien

    2015-04-01

    Earthworms can have strong direct effects on plant communities through consumption and digestion of seeds, however it is unclear how earthworms may influence the relative abundance and composition of plant communities invaded by non-native species. In this study, earthworms, seed banks, and the standing vegetation were sampled in a grassland of central California. Our objectives were i) to examine whether the abundances of non-native, invasive earthworm species and non-native grassland plant species are correlated, and ii) to test whether seed ingestion by these worms alters the soil seed bank by evaluating the composition of seeds in casts relative to uningested soil. Sampling locations were selected based on historical land-use practices, including presence or absence of tilling, and revegetation by seed using Phalaris aquatica. Only non-native earthworm species were found, dominated by the invasive European species Aporrectodea trapezoides. Earthworm abundance was significantly higher in the grassland blocks dominated by non-native plant species, and these sites had higher carbon and moisture contents. Earthworm abundance was also positively related to increased emergence of non-native seedlings, but had no effect on that of native seedlings. Plant species richness and total seedling emergence were higher in casts than in uningested soils. This study suggests that there is a potential effect of non-native earthworms in promoting non-native and likely invasive plant species within grasslands, due to seed-plant-earthworm interactions via soil modification or to seed ingestion by earthworms and subsequent cast effects on grassland dynamics. This study supports a growing body of literature for earthworms as ecosystem engineers but highlights the relative importance of considering non-native-native interactions with the associated plant community.

  15. Literature-derived bioaccumulation models for earthworms: Development and validation

    SciTech Connect

    Sample, B.E.; Suter, G.W. II; Beauchamp, J.J.; Efroymson, R.A.

    1999-09-01

    Estimation of contaminant concentrations in earthworms is a critical component in many ecological risk assessments. Without site-specific data, literature-derived uptake factors or models are frequently used. Although considerable research has been conducted on contaminant transfer from soil to earthworms, most studies focus on only a single location. External validation of transfer models has not been performed. The authors developed a database of soil and tissue concentrations for nine inorganic and two organic chemicals. Only studies that presented total concentrations in departed earthworms were included. Uptake factors and simple and multiple regression models of natural-log-transformed concentrations of each analyte in soil and earthworms were developed using data from 26 studies. These models were then applied to data from six additional studies. Estimated and observed earthworm concentrations were compared using nonparametric Wilcoxon signed-rank tests. Relative accuracy and quality of different estimation methods were evaluated by calculating the proportional deviation of the estimate from the measured value. With the exception of Cr, significant, single-variable (e.g., soil concentration) regression models were fit for each analyte. Inclusion of soil Ca improved model fits for Cd and Pb. Soil pH only marginally improved model fits. The best general estimates of chemical concentrations in earthworms were generated by simple ln-ln regression models for As, Cd, Cu, Hg, Mn, Pb, Zn, and polychlorinated biphenyls. No method accurately estimated Cr or Ni in earthworms. Although multiple regression models including pH generated better estimates for a few analytes, in general, the predictive utility gained by incorporating environmental variables was marginal.

  16. Earthworm ecotoxicological assessments of pesticides used to treat seeds under tropical conditions.

    PubMed

    Alves, Paulo Roger L; Cardoso, Elke J B N; Martines, Alexandre M; Sousa, José Paulo; Pasini, Amarildo

    2013-03-01

    Ecotoxicological laboratory tests (lower-tier tests) are fundamental tools for assessing the toxicity of pesticides to soil organisms. In this study, using these tests under tropical conditions, we quantified the impact of the insecticides imidacloprid, fipronil, and thiametoxam, and the fungicides captan and carboxin+thiram, all of which are used in the chemical treatment of crop seeds, on the survival, reproduction, and behavior of Eisenia andrei (Oligochaeta). With the exception of imidacloprid, none of the pesticides tested caused mortality in E. andrei in artificial soils. The LC(50) of imidacloprid was estimated as 25.53 mg active ingredient kg(-1) of dry soil. Earthworm reproduction rates were reduced by imidacloprid (EC(50)=4.07 mgkg(-1)), fipronil (EC(20)=23.16 mgkg(-1)), carboxin+thiram (EC(50)=56.38 mgkg(-1)), captan (EC(50)=334.84 mgkg(-1)), and thiametoxam (EC(50)=791.99 mgkg(-1)). Avoidance behavior was observed in the presence of imidacloprid (AC(50)=0.11 mgkg(-1)), captan (AC(50)=33.54 mgkg(-1)), carboxin+thiram (AC(50)=60.32 mgkg(-1)), and thiametoxam (AC(50)=>20 mgkg(-1)). Earthworms showed a preference for soils with the insecticide fipronil. Imidacloprid was the most toxic of the substances tested for E. andrei. The avoidance test was the most sensitive test for most pesticides studied, but results varied between pesticides. These results offer new insights on the toxicity of pesticides used to treat seeds in tropical regions. However, they should be complemented with higher-tier tests in order to reduce the uncertainties in risk assessment. PMID:23261124

  17. Microbial enzyme and biomass responses: Deciphering the effects of earthworms and seasonal variation on treating excess sludge.

    PubMed

    Ma, Xiaojie; Xing, Meiyan; Wang, Yin; Xu, Zhe; Yang, Jian

    2016-04-01

    This paper reports on a seasonal pattern comparison of microbial enzymatic activities and biomass responses based on a conventional biofilter (BF, without earthworm) and a vermifilter (VF, with earthworm, Eisenia fetida) for excess sludge treatment. The volatile suspended solids (VSS) reduction, viable cell number and enzyme activities were assayed to probe what made the VF operate stably. The results indicated that the earthworm activities can polish the VSS reduction with 27.17% more than the BF. Though the VF had a lower level in the viable cell number compared with the BF, the earthworm strongly improved the microbial enzymatic activities such as INT-dehydrogenase, protease, β-glucosidase and amylase, which can explain the excellent performance of VSS reduction. The correlation analysis documented that the VSS reduction was positively correlated with microbial enzyme activities. More importantly, the earthworm enabled the VF to avoid the detrimental influence of temperature, which guaranteed a stable performance during seasonal variations. PMID:26840985

  18. Effects of anesthetic compounds on responses of earthworms to electrostimulation.

    PubMed

    Podolak-Machowska, Agnieszka; Kostecka, Joanna; Librowski, Tadeusz; Santocki, Michal; Bigaj, Janusz; Plytycz, Barbara

    2014-01-01

    Earthworms play an important role in biomedical research, and some surgical procedures require anesthesia. Anesthetic treatments used so far usually induce convulsive body movements connected with extrusion of coelomocyte-containing coelomic fluid that may affect experimental results. Extensive movements connected with the expulsion of coelomic fluid are exploited by immunologists as a method of harvesting immunocompetent coelomocytes from worms subjected to mild electrostimulation (4.5V). The aim of the investigations was to find anesthetic drugs without unintentional coelomocyte depletion. Experiments were performed on adult specimens of Dendrobaena veneta, the coelomocytes of which consist of amoebocytes and riboflavin-storing eleocytes. Earthworm mobility was filmed and extrusion of coelomocytes was quantified by detection of eleocyte-derived riboflavin in immersion fluid. Treatments included earthworms (1) immersed either in physiological saline (controls) or in a solution of one of the tested anesthetic drugs; (2) electrostimulated immediately after anesthesia, and (3) electrostimulated a second time after a 1-hour recovery period. The well-established fish and amphibian anesthetic agent MS-222 induced coelomocyte expulsion. In contrast, solutions of the mammalian local anesthetic drug, prilocaine hydrochloride (0.25-0.5%, 5-10 min) caused temporal earthworm immobilization followed by recovery, thus showing utility as an efficient earthworm anesthetic. PMID:25134346

  19. A spatial paradigm, the allothetic place avoidance alternation task, for testing visuospatial working memory and skill learning in rats.

    PubMed

    Dockery, Colleen A; Wesierska, Malgorzata J

    2010-08-30

    We present a paradigm for assessing visuospatial working memory and skill learning in a rodent model, based on the place avoidance test. In our allothetic place avoidance alternation task (APAAT) the paradigm is comprised of minimal training sessions, tests various aspects of learning and memory and provides a rich set of parameters. A single working memory session consists of four conditions: habituation (no shock), two place avoidance training intervals (shock activated) and a retrieval test (shock inactivated). The location of the shock sector is alternated for each training day which initially requires extinction of previous representations and further working memory to achieve effective place avoidance across sessions. Visuospatial skill memory was evaluated by the shock/entrance ratio by tracking locomotor activity which is essential to execute a place avoidance strategy. For each day rats learned to avoid a new place with shock, as shown by a decreased number of entrances, and an increased time to the first entrance and maximum avoidance time. Skill learning improved according to the decreased number of shocks per entrance across conditions. These results indicate that complex cognitive functions are captured by this behavioral method. This APAAT paradigm expands and complements existing tools for studying hippocampal-prefrontal dependent functions to support development of treatment interventions. PMID:20603147

  20. Methods for the assessment of the toxicity of environmental chemicals to earthworms

    SciTech Connect

    Dean-Ross, D.

    1983-03-01

    In view of the impending publication of standards for earthworm toxicity testing by the Commission of the European Communities, a review has been made of the recent literature on earthworm toxicology. Relevant studies are reviewed from the standpoints of methods used, reproducibility of results, and ability to extrapolate laboratory results to field situations. Eisenia foetida, a commonly used test species, is much less sensitive to agricultural chemicals than other, native earthworms and is of doubtful utility for extrapolating laboratory data to field conditions, but when native soil organisms are used, such extrapolations show good general agreement. Standardization of test conditions and broadening of the data base are encouraged.

  1. For Better Soil, Let Earthworms Toil.

    ERIC Educational Resources Information Center

    Swinehart, Rebecca, Ed.

    1995-01-01

    This activity involves elementary students in investigating how earthworms affect soil fertility. An introduction discusses topsoil loss and the connections between soil and earthworm ecology. Materials needed and step-by-step procedure are provided. (LZ)

  2. Soil contamination evaluations: Earthworms as indicators of soil quality

    SciTech Connect

    Linder, G.; Wilbom, D.

    1995-12-31

    Earthworms have frequently been evaluated in the field and laboratory as representatives of the soil community that are indicative of their habitat`s quality. Within a landscape or at a contaminated site, soil quality, or soil health, has become increasingly critical to cleanup-related issues that revolve around questions of ``how clean is clean`` and the bioaccumulation of soil contaminants. Through an overview of numerous field and laboratory studies, the role that earthworms have played in evaluating soil contamination will be reviewed with a particular focus on evaluations of the bioaccumulation potential of chemicals in soil. Within ecological contexts, earthworms can provide information regarding immediately observable adverse affects related, for example, to acute toxicity. Additionally, earthworms can provide information directly related to the bioaccumulation potential of a chemical and trophic transfer of environmental chemicals, especially through the food-chain. Within the decision-making process, soil contamination evaluations must consider future land-use, as well as current and future expressions of adverse biological and ecological effects under field conditions, potentially following remediation. Through integrated field and laboratory studies using earthworms, the authors have been able to identify adversely affected soil communities and have been able to provide information for assessing adverse ecological effects potentially caused by contaminants. Field surveys and on-site or in situ biological testing with earthworms, however, can not alone identify causes of effects. As such, standardized biological tests have been routinely completed in the laboratory so linkages between expression of effects and contaminants could be more readily addressed in conjunction with appropriate chemical data from the field.

  3. Flight test evaluation of a prototype optical instrument for airborne sense-and-avoid applications

    NASA Astrophysics Data System (ADS)

    Minwalla, Cyrus; Thomas, Paul; Ellis, Kristopher; Hornsey, Richard; Jennings, Sion

    2012-06-01

    A prototype, wide-field, optical sense-and-avoid instrument was constructed from low-cost commercial off-the-shelf components, and configured as a network of smart camera nodes. To detect small, general-aviation aircraft in a timely manner, such a sensor must detect targets at a range of 5-10 km at an update rate of a few Hz. This paper evaluates the flight test performance of the "DragonflEYE" sensor as installed on a Bell 205 helicopter. Both the Bell 205 and the Bell 206 (intruder aircraft) were fully instrumented to record position and orientation. Emphasis was given to the critical case of head-on collisions at typical general aviation altitudes and airspeeds. Imagery from the DragonflEYE was stored for the offline assessment of performance. Methodologies for assessing the key figures of merit, such as the signal-to-noise ratio, the range at first detection (R0) and angular target size were developed. Preliminary analysis indicated an airborne detection range of 6:7 km under typical visual meteorological conditions, which significantly exceeded typical visual acquisition ranges under the same conditions.

  4. Avoidance of harvesting and sampling artefacts in hydraulic analyses: a protocol tested on Malus domestica.

    PubMed

    Beikircher, Barbara; Mayr, Stefan

    2016-06-01

    A prerequisite for reliable hydraulic measurements is an accurate collection of the plant material. Thereby, the native hydraulic state of the sample has to be preserved during harvesting (i.e., cutting the plant or plant parts) and preparation (i.e., excising the target section). This is particularly difficult when harvesting has to be done under transpiring conditions. In this article, we present a harvesting and sampling protocol designed for hydraulic measurements on Malus domestica Borkh. and checked for possible sampling artefacts. To test for artefacts, we analysed the percentage loss of hydraulic conductivity, maximum specific conductivity and water contents of bark and wood of branches, taking into account conduit length, time of day of harvesting, different shoot ages and seasonal effects. Our results prove that use of appropriate protocols can avoid artefactual embolization or refilling even when the xylem is under tension at harvest. The presented protocol was developed for Malus but may also be applied for other angiosperms with similar anatomy and refilling characteristics. PMID:26705311

  5. Avoidance of harvesting and sampling artefacts in hydraulic analyses: a protocol tested on Malus domestica

    PubMed Central

    Beikircher, Barbara; Mayr, Stefan

    2016-01-01

    A prerequisite for reliable hydraulic measurements is an accurate collection of the plant material. Thereby, the native hydraulic state of the sample has to be preserved during harvesting (i.e., cutting the plant or plant parts) and preparation (i.e., excising the target section). This is particularly difficult when harvesting has to be done under transpiring conditions. In this article, we present a harvesting and sampling protocol designed for hydraulic measurements on Malus domestica Borkh. and checked for possible sampling artefacts. To test for artefacts, we analysed the percentage loss of hydraulic conductivity, maximum specific conductivity and water contents of bark and wood of branches, taking into account conduit length, time of day of harvesting, different shoot ages and seasonal effects. Our results prove that use of appropriate protocols can avoid artefactual embolization or refilling even when the xylem is under tension at harvest. The presented protocol was developed for Malus but may also be applied for other angiosperms with similar anatomy and refilling characteristics. PMID:26705311

  6. Phi Index: A New Metric to Test the Flush Early and Avoid the Rush Hypothesis

    PubMed Central

    Samia, Diogo S. M.; Blumstein, Daniel T.

    2014-01-01

    Optimal escape theory states that animals should counterbalance the costs and benefits of flight when escaping from a potential predator. However, in apparent contradiction with this well-established optimality model, birds and mammals generally initiate escape soon after beginning to monitor an approaching threat, a phenomena codified as the “Flush Early and Avoid the Rush” (FEAR) hypothesis. Typically, the FEAR hypothesis is tested using correlational statistics and is supported when there is a strong relationship between the distance at which an individual first responds behaviorally to an approaching predator (alert distance, AD), and its flight initiation distance (the distance at which it flees the approaching predator, FID). However, such correlational statistics are both inadequate to analyze relationships constrained by an envelope (such as that in the AD-FID relationship) and are sensitive to outliers with high leverage, which can lead one to erroneous conclusions. To overcome these statistical concerns we develop the phi index (Φ), a distribution-free metric to evaluate the goodness of fit of a 1∶1 relationship in a constraint envelope (the prediction of the FEAR hypothesis). Using both simulation and empirical data, we conclude that Φ is superior to traditional correlational analyses because it explicitly tests the FEAR prediction, is robust to outliers, and it controls for the disproportionate influence of observations from large predictor values (caused by the constrained envelope in AD-FID relationship). Importantly, by analyzing the empirical data we corroborate the strong effect that alertness has on flight as stated by the FEAR hypothesis. PMID:25405872

  7. Testing the role of reward and punishment sensitivity in avoidance behavior: a computational modeling approach

    PubMed Central

    Sheynin, Jony; Moustafa, Ahmed A.; Beck, Kevin D.; Servatius, Richard J.; Myers, Catherine E.

    2015-01-01

    Exaggerated avoidance behavior is a predominant symptom in all anxiety disorders and its degree often parallels the development and persistence of these conditions. Both human and non-human animal studies suggest that individual differences as well as various contextual cues may impact avoidance behavior. Specifically, we have recently shown that female sex and inhibited temperament, two anxiety vulnerability factors, are associated with greater duration and rate of the avoidance behavior, as demonstrated on a computer-based task closely related to common rodent avoidance paradigms. We have also demonstrated that avoidance is attenuated by the administration of explicit visual signals during “non-threat” periods (i.e., safety signals). Here, we use a reinforcement-learning network model to investigate the underlying mechanisms of these empirical findings, with a special focus on distinct reward and punishment sensitivities. Model simulations suggest that sex and inhibited temperament are associated with specific aspects of these sensitivities. Specifically, differences in relative sensitivity to reward and punishment might underlie the longer avoidance duration demonstrated by females, whereas higher sensitivity to punishment might underlie the higher avoidance rate demonstrated by inhibited individuals. Simulations also suggest that safety signals attenuate avoidance behavior by strengthening the competing approach response. Lastly, several predictions generated by the model suggest that extinction-based cognitive-behavioral therapies might benefit from the use of safety signals, especially if given to individuals with high reward sensitivity and during longer safe periods. Overall, this study is the first to suggest cognitive mechanisms underlying the greater avoidance behavior observed in healthy individuals with different anxiety vulnerabilities. PMID:25639540

  8. The role of experiential avoidance in acute pain tolerance: a laboratory test.

    PubMed

    Feldner, Matthew T; Hekmat, Hamid; Zvolensky, Michael J; Vowles, Kevin E; Secrist, Zachary; Leen-Feldner, Ellen W

    2006-06-01

    The present investigation examined the role of experiential avoidance in terms of acute pain tolerance and subsequent recovery. Seventy nonclinical participants completed the Acceptance and Action Questionnaire and underwent a well-established cold pressor task. Results indicated that individuals reporting higher levels of experiential avoidance had lower pain endurance and tolerance and recovered more slowly from this particular type of aversive event. Consistent with theoretical prediction, these findings suggest that experiential avoidance may play a role in tolerance of acute pain. PMID:15882839

  9. Warming shifts `worming': effects of experimental warming on invasive earthworms in northern North America

    NASA Astrophysics Data System (ADS)

    Eisenhauer, Nico; Stefanski, Artur; Fisichelli, Nicholas A.; Rice, Karen; Rich, Roy; Reich, Peter B.

    2014-11-01

    Climate change causes species range shifts and potentially alters biological invasions. The invasion of European earthworm species across northern North America has severe impacts on native ecosystems. Given the long and cold winters in that region that to date supposedly have slowed earthworm invasion, future warming is hypothesized to accelerate earthworm invasions into yet non-invaded regions. Alternatively, warming-induced reductions in soil water content (SWC) can also decrease earthworm performance. We tested these hypotheses in a field warming experiment at two sites in Minnesota, USA by sampling earthworms in closed and open canopy in three temperature treatments in 2010 and 2012. Structural equation modeling revealed that detrimental warming effects on earthworm densities and biomass could indeed be partly explained by warming-induced reductions in SWC. The direction of warming effects depended on the current average SWC: warming had neutral to positive effects at high SWC, whereas the opposite was true at low SWC. Our results suggest that warming limits the invasion of earthworms in northern North America by causing less favorable soil abiotic conditions, unless warming is accompanied by increased and temporally even distributions of rainfall sufficient to offset greater water losses from higher evapotranspiration.

  10. Earthworms drive succession of both plant and Collembola communities in post-mining sites

    NASA Astrophysics Data System (ADS)

    Mudrák, Obdřej; Frouz, Jan

    2015-04-01

    Previous field observations indicated that earthworms promote late-successional plant species and reduce collembolan numbers at post-mining sites in the Sokolov coal mining district (Czech Republic). Here, we established a laboratory pot experiment to test the effect of earthworms (Aporrectodea caliginosa Savigny and Lumbricus rubellus Hoffm.) and litter of low, medium, and high quality (the grass Calamagrostis epigejos, the willow Salix caprea, and the alder Alnus glutinosa, respectively) on late successional plants (grasses Arrhenatherum elatius and Agrostis capillaris, legumes Lotus corniculatus and Trifolium medium, and non-leguminous dicots Centaurea jacea and Plantago lanceolata) in spoil substrate originating from Sokolov post-mining sites and naturally inhabited by abundant numbers of Collembola. The earthworms increased plant biomass, especially that of the large-seeded A. elatius, but reduced the number of plant individuals, mainly that of the small-seeded A. capillaris and both legumes. Litter quality affected plant biomass, which was highest with S. caprea litter, but did not change the number of plant individuals. Litter quality did not modify the effect of earthworms on plants; the effect of litter quality and earthworms was only additive. Species composition of Collembola community was altered by litter quality, but earthworms reduced the number of individuals, increased the number of species, and increased species evenness consistently across the litter qualities. Because the results of this experiment were consistent with the field observations, we conclude that earthworms help drive succession of both plant and Collembola communities on post-mining sites.

  11. Earthworms drive succession of both plant and Collembola communities in post-mining sites

    NASA Astrophysics Data System (ADS)

    Mudrák, Ondřej; Uteseny, Karoline; Frouz, Jan

    2016-04-01

    Previous field observations indicated that earthworms promote late-successional plant species and reduce collembolan numbers at post-mining sites in the Sokolov coal mining district (Czech Republic). Here, we established a laboratory pot experiment to test the effect of earthworms (Aporrectodea caliginosa Savigny and Lumbricus rubellus Hoffm.) and litter of low, medium, and high quality (the grass Calamagrostis epigejos, the willow Salix caprea, and the alder Alnus glutinosa, respectively) on late successional plants (grasses Arrhenatherum elatius and Agrostis capillaris, legumes Lotus corniculatus and Trifolium medium, and non-leguminous dicots Centaurea jacea and Plantago lanceolata) in spoil substrate originating from Sokolov post-mining sites and naturally inhabited by abundant numbers of Collembola. The earthworms increased plant biomass, especially that of the large-seeded A. elatius, but reduced the number of plant individuals, mainly that of the small-seeded A. capillaris and both legumes. Litter quality affected plant biomass, which was highest with S. caprea litter, but did not change the number of plant individuals. Litter quality did not modify the effect of earthworms on plants; the effect of litter quality and earthworms was only additive. Species composition of Collembola community was altered by litter quality, but earthworms reduced the number of individuals, increased the number of species, and increased species evenness consistently across the litter qualities. Because the results of this experiment were consistent with the field observations, we conclude that earthworms help drive succession of both plant and Collembola communities on post-mining sites.

  12. Earthworms Use Odor Cues to Locate and Feed on Microorganisms in Soil

    PubMed Central

    Zirbes, Lara; Mescher, Mark; Vrancken, Véronique; Wathelet, Jean-Paul; Verheggen, François J.; Thonart, Philippe; Haubruge, Eric

    2011-01-01

    Earthworms are key components of temperate soil ecosystems but key aspects of their ecology remain unexamined. Here we elucidate the role of olfactory cues in earthworm attraction to food sources and document specific chemical cues that attract Eisenia fetida to the soil fungi Geotrichum candidum. Fungi and other microorganisms are major sources of volatile emissions in soil ecosystems as well as primary food sources for earthworms, suggesting the likelihood that earthworms might profitably use olfactory cues to guide foraging behavior. Moreover, previous studies have documented earthworm movement toward microbial food sources. But, the specific olfactory cues responsible for earthworm attraction have not previously been identified. Using olfactometer assays combined with chemical analyses (GC-MS), we documented the attraction of E. fetida individuals to filtrate derived from G. candidum colonies and to two individual compounds tested in isolation: ethyl pentanoate and ethyl hexanoate. Attraction at a distance was observed when barriers prevented the worms from reaching the target stimuli, confirming the role of volatile cues. These findings enhance our understanding of the mechanisms underlying key trophic interactions in soil ecosystems and have potential implications for the extraction and collection of earthworms in vermiculture and other applied activities. PMID:21799756

  13. Warming shifts ‘worming': effects of experimental warming on invasive earthworms in northern North America

    PubMed Central

    Eisenhauer, Nico; Stefanski, Artur; Fisichelli, Nicholas A.; Rice, Karen; Rich, Roy; Reich, Peter B.

    2014-01-01

    Climate change causes species range shifts and potentially alters biological invasions. The invasion of European earthworm species across northern North America has severe impacts on native ecosystems. Given the long and cold winters in that region that to date supposedly have slowed earthworm invasion, future warming is hypothesized to accelerate earthworm invasions into yet non-invaded regions. Alternatively, warming-induced reductions in soil water content (SWC) can also decrease earthworm performance. We tested these hypotheses in a field warming experiment at two sites in Minnesota, USA by sampling earthworms in closed and open canopy in three temperature treatments in 2010 and 2012. Structural equation modeling revealed that detrimental warming effects on earthworm densities and biomass could indeed be partly explained by warming-induced reductions in SWC. The direction of warming effects depended on the current average SWC: warming had neutral to positive effects at high SWC, whereas the opposite was true at low SWC. Our results suggest that warming limits the invasion of earthworms in northern North America by causing less favorable soil abiotic conditions, unless warming is accompanied by increased and temporally even distributions of rainfall sufficient to offset greater water losses from higher evapotranspiration. PMID:25363633

  14. Warming shifts 'worming': effects of experimental warming on invasive earthworms in northern North America.

    PubMed

    Eisenhauer, Nico; Stefanski, Artur; Fisichelli, Nicholas A; Rice, Karen; Rich, Roy; Reich, Peter B

    2014-01-01

    Climate change causes species range shifts and potentially alters biological invasions. The invasion of European earthworm species across northern North America has severe impacts on native ecosystems. Given the long and cold winters in that region that to date supposedly have slowed earthworm invasion, future warming is hypothesized to accelerate earthworm invasions into yet non-invaded regions. Alternatively, warming-induced reductions in soil water content (SWC) can also decrease earthworm performance. We tested these hypotheses in a field warming experiment at two sites in Minnesota, USA by sampling earthworms in closed and open canopy in three temperature treatments in 2010 and 2012. Structural equation modeling revealed that detrimental warming effects on earthworm densities and biomass could indeed be partly explained by warming-induced reductions in SWC. The direction of warming effects depended on the current average SWC: warming had neutral to positive effects at high SWC, whereas the opposite was true at low SWC. Our results suggest that warming limits the invasion of earthworms in northern North America by causing less favorable soil abiotic conditions, unless warming is accompanied by increased and temporally even distributions of rainfall sufficient to offset greater water losses from higher evapotranspiration. PMID:25363633

  15. [Acute toxicological effects of heavy metal pollution in soils on earthworms].

    PubMed

    Song, Yufang; Zhou, Qixing; Xu, Huaxia; Ren, Liping; Sun, Tieheng; Gong, Ping

    2002-02-01

    Acute and sub-acute lethal effects of single and combined Cu, Zn, Pb and Cd on earthworm was determined using meadow brown soil. Results indicated that the mortality of earthworm was significantly related with the concentrations of Cu and Zn in the soil (alpha = 0.05, RCu = 0.86, RPb = 0.87), and the inhibition rate of earthworm growth was significantly related with the concentration of Cu in the soil (alpha = 0.05, RCu = 0.84). There was no significant relation between the concentrations of other heavy metals tested and the death rate and the growth-inhibition rate. The degree of individual earthworm enduring the toxicity of heavy metals varied greatly. The threshold concentration of toxicity defined by statistical method, the level to conduce the death of individual earthworm was 300 mg.kg-1 for Cu, 1300 mg.kg-1 for Zn, 1700 mg.kg-1 for Pb, 300 mg.kg-1 for Cd. LC50 was 400-450 mg.kg-1 for Cu, 1500-1900 mg.kg-1 for Zn, 2350-2400 mg.kg-1 for Pb and 900 mg.kg-1 for Cd. Combined effects of single Cu, Zn, Pb and Cd to conduce more than 10% of the death rate of earthworm could result in 100% of the death rate of earthworm, thus showing the strong synergistic joint effect of the heavy metals. PMID:11993124

  16. Lethal and sub-lethal effects of five pesticides used in rice farming on the earthworm Eisenia fetida.

    PubMed

    Rico, Andreu; Sabater, Consuelo; Castillo, María-Ángeles

    2016-05-01

    The toxicity of five pesticides typically used in rice farming (trichlorfon, dimethoate, carbendazim, tebuconazole and prochloraz) was evaluated on different lethal and sub-lethal endpoints of the earthworm Eisenia fetida. The evaluated endpoints included: avoidance behaviour after an exposure period of 2 days; and mortality, weight loss, enzymatic activities (cholinesterase, lactate dehydrogenase and alkaline phosphatase) and histopathological effects after an exposure period of 14 days. Carbendazim was found to be highly toxic to E. fetida (LC50=2mg/kg d.w.), significantly reducing earthworm weight and showing an avoidance response at soil concentrations that are close to those predicted in rice-fields and in surrounding ecosystems. The insecticide dimethoate showed a moderate acute toxicity (LC50=28mg/kg d.w.), whereas the rest of tested pesticides showed low toxicity potential (LC50 values above 100mg/kg d.w.). For these pesticides, however, weight loss was identified as a sensitive endpoint, with NOEC values approximately 2 times or lower than the calculated LC10 values. The investigated effects on the enzymatic activities of E. fetida and the observed histopathological alterations (longitudinal and circular muscle lesions, edematous tissues, endothelial degeneration and necrosis) proved to be sensitive biomarkers to monitor pesticide contamination and are proposed as alternative measures to evaluate pesticide risks on agro-ecosystems. PMID:26874341

  17. Automated Analysis of Two-Dimensional Positions and Body Lengths of Earthworms (Oligochaeta); MimizuTrack

    PubMed Central

    Yonemura, Seiichiro; Kaneda, Satoshi; Ohashi, Mizue; Ikeno, Hidetoshi

    2014-01-01

    Earthworms are important soil macrofauna inhabiting almost all ecosystems. Their biomass is large and their burrowing and ingestion of soils alters soil physicochemical properties. Because of their large biomass, earthworms are regarded as an indicator of “soil heath”. However, primarily because the difficulties in quantifying their behavior, the extent of their impact on soil material flow dynamics and soil health is poorly understood. Image data, with the aid of image processing tools, are a powerful tool in quantifying the movements of objects. Image data sets are often very large and time-consuming to analyze, especially when continuously recorded and manually processed. We aimed to develop a system to quantify earthworm movement from video recordings. Our newly developed program successfully tracked the two-dimensional positions of three separate parts of the earthworm and simultaneously output the change in its body length. From the output data, we calculated the velocity of the earthworm's movement. Our program processed the image data three times faster than the manual tracking system. To date, there are no existing systems to quantify earthworm activity from continuously recorded image data. The system developed in this study will reduce input time by a factor of three compared with manual data entry and will reduce errors involved in quantifying large data sets. Furthermore, it will provide more reliable measured values, although the program is still a prototype that needs further testing and improvement. Combined with other techniques, such as measuring metabolic gas emissions from earthworm bodies, this program could provide continuous observations of earthworm behavior in response to environmental variables under laboratory conditions. In the future, this standardized method will be applied to other animals, and the quantified earthworm movement will be incorporated into models of soil material flow dynamics or behavior in response to chemical

  18. Ecological and geochemical impacts of exotic earthworm dispersal in forest ecosystems of Eastern Canada

    NASA Astrophysics Data System (ADS)

    Drouin, Melanie; Fugere, Martine; Lapointe, Line; Vellend, Mark; Bradley, Robert L.

    2016-04-01

    In Eastern Canada, native earthworm species did not survive the Wisconsin glaciation, which ended over 11,000 years ago. Accordingly, the 17 known Lumbricidae species in the province of Québec were introduced in recent centuries by European settlers. Given that natural migration rates are no more than 5-10 m yr‑1, exotic earthworm dispersal across the landscape is presumed to be mediated by human activities, although this assertion needs further validation. In agroecosystems, earthworms have traditionally been considered beneficial soil organisms that facilitate litter decomposition, increase nutrient availability and improve soil structure. However, earthworm activities could also increase soil nutrient leaching and CO2 emissions. Furthermore, in natural forest ecosystems, exotic earthworms may reduce organic forest floors provoking changes in watershed hydrology and loss of habitat for some faunal species. Over the past decade, studies have also suggested a negative effect of exotic earthworms on understory plant diversity, but the underlying mechanisms remain elusive. Finally, there are no studies to our knowledge that have tested the effects of Lumbricidae species on the production of N2O (an important greenhouse gas) in forest ecosystems. We report on a series of field, greenhouse and laboratory studies on the human activities responsible for the dispersal of exotic earthworms, and on their ecological / geochemical impacts in natural forest ecosystems. Our results show: (1) Car tire treads and bait discarded by fishermen are important human vectors driving the dispersal of earthworms into northern temperate forests; (2) Exotic earthworms significantly modify soil physicochemical properties, nutrient cycling, microbial community structure and biomass; (3) Earthworm abundances in the field correlate with a decrease in understory plant diversity; (4) Lumbricus terrestris, an anecic earthworm species and favorite bait of fishermen, reduces seed germination and

  19. Node-avoiding Levy flight - A numerical test of the epsilon expansion. [random walk

    NASA Technical Reports Server (NTRS)

    Halley, J. W.; Nakanishi, H.

    1985-01-01

    A study is conducted of an extension of Levy flight to include self-repulsion in the path of the walk. The extension is called node-avoiding Levy flight and its equivalence to the n approaches 0 limit of a statistical mechanical model for a magnetic system with long-range interactions between the spins is shown. By use of this equivalence it is possible to make a detailed comparison beween the results of the epsilon expansion for the magnetic model, a Monte Carlo simulation of the Levy flight model, and the results of a Flory-type argument. This is the first comparison of the epsilon expansion for epsilon much less than 1 with a numerical simulation for any model. Some speculations are made on applications of the model of node-avoiding Levy flight.

  20. Earthworms accumulate alanine in response to drought.

    PubMed

    Holmstrup, Martin; Slotsbo, Stine; Henriksen, Per G; Bayley, Mark

    2016-09-01

    Earthworms have ecologically significant functions in tropical and temperate ecosystems and it is therefore important to understand how these animals survive during drought. In order to explore the physiological responses to dry conditions, we simulated a natural drought incident in a laboratory trial exposing worms in slowly drying soil for about one month, and then analyzed the whole-body contents of free amino acids (FAAs). We investigated three species forming estivation chambers when soils dry out (Aporrectodea tuberculata, Aporrectodea icterica and Aporrectodea longa) and one species that does not estivate during drought (Lumbricus rubellus). Worms subjected to drought conditions (< -2MPa) substantially increased the concentration of FAAs and in particular alanine that was significantly upregulated in all tested species. Alanine was the most important FAA reaching 250-650μmolg(-1) dry weight in dehydrated Aporrectodea species and 300μmolg(-1) dry weight in L. rubellus. Proline was only weakly upregulated in some species as were a few other FAAs. Species forming estivation chambers (Aporrectodea spp.) did not show a better ability to conserve body water than the non-estivating species (L. rubellus) at the same drought level. These results suggest that the accumulation of alanine is an important adaptive trait in drought tolerance of earthworms in general. PMID:27107492

  1. Testing the disgust conditioning theory of food-avoidance in adolescents with recent onset anorexia nervosa.

    PubMed

    Hildebrandt, Tom; Grotzinger, Andrew; Reddan, Marianne; Greif, Rebecca; Levy, Ifat; Goodman, Wayne; Schiller, Daniela

    2015-08-01

    Anorexia nervosa is characterized by chronic food avoidance that is resistant to change. Disgust conditioning offers one potential unexplored mechanism for explaining this behavioral disturbance because of its specific role in facilitating food avoidance in adaptive situations. A food based reversal learning paradigm was used to study response flexibility in 14 adolescent females with restricting subtype anorexia nervosa (AN-R) and 15 healthy control (HC) participants. Expectancy ratings were coded as a behavioral measure of flexibility and electromyography recordings from the levator labii (disgust), zygomaticus major (pleasure), and corrugator (general negative affect) provided psychophysiological measures of emotion. Response inflexibility was higher for participants with AN-R, as evidenced by lower extinction and updated expectancy ratings during reversal. EMG responses to food stimuli were predictive of both extinction and new learning. Among AN-R patients, disgust specific responses to food were associated with impaired extinction, as were elevated pleasure responses to the cued absence of food. Disgust conditioning appears to influence food learning in acutely ill patients with AN-R and may be maintained by counter-regulatory acquisition of a pleasure response to food avoidance and an aversive response to food presence. Developing strategies to target disgust may improve existing interventions for patients with AN. PMID:26131915

  2. Sub-Lethal Effects of Copper on Salmonids: An Avoidance Evaluation Using a Direct Test Method.

    PubMed

    Van Genderen, Eric L; Dishman, Diana L; Ray Arnold, W; Gorsuch, Joseph W; Call, Daniel J

    2016-07-01

    Avoidance of copper (Cu) by rainbow trout (Oncorhynchus mykiss) was evaluated using a Y-maze exposure system, with data collected over a 1-h exposure period using a digital camcorder. In exposures to five measured concentrations of dissolved copper (<0.3, 1.2, 9.8, 48.3, and 98.6 µg Cu/L), plus control, significant avoidance behavior (p < 0.05) relative to the control was observed at ≥9.8 µg Cu/L, but not at 1.2 µg Cu/L. The chronic value (i.e., geometric mean of these concentrations) was 3.43 µg Cu/L. Estimates of EC50 values for avoidance of Cu ranged from 4.81 to 9.15 µg Cu/L over four 15-min time intervals of exposure to the metal. Based on water quality characterization of the control/diluent water, the U.S. Environmental Protection Agency (USEPA) water hardness- and biotic ligand model (BLM)-based chronic criteria for dissolved Cu were 8.03 and 2.26 µg Cu/L, respectively. This study suggested that enforcement of the BLM-based criterion would provide a higher level of protection of trout for this sensitive response than the hardness-based criterion. PMID:27025764

  3. Why Do Fearful Facial Expressions Elicit Behavioral Approach? Evidence From a Combined Approach-Avoidance Implicit Association Test

    PubMed Central

    Hammer, Jennifer L.; Marsh, Abigail A.

    2015-01-01

    Despite communicating a “negative” emotion, fearful facial expressions predominantly elicit behavioral approach from perceivers. It has been hypothesized that this seemingly paradoxical effect may occur due to fearful expressions’ resemblance to vulnerable, infantile faces. However, this hypothesis has not yet been tested. We used a combined approach-avoidance/implicit association test (IAT) to test this hypothesis. Participants completed an approach-avoidance lever task during which they responded to fearful and angry facial expressions as well as neutral infant and adult faces presented in an IAT format. Results demonstrated an implicit association between fearful facial expressions and infant faces and showed that both fearful expressions and infant faces primarily elicit behavioral approach. The dominance of approach responses to both fearful expressions and infant faces decreased as a function of psychopathic personality traits. Results suggest that the prosocial responses to fearful expressions observed in most individuals may stem from their associations with infantile faces. PMID:25603135

  4. Earthworm contamination by PCBs and heavy metals

    SciTech Connect

    Diercxsens, P.; de Weck, D.; Borsinger, N.; Rosset, B.; Tarradellas, J.

    1985-01-01

    A comparison is made of soil and earthworm contamination by PCBs and heavy metals between a nature reserve and two sites conditioned by the addition of sewage sludge and compost. The tissues and gut content of the earthworms shows a higher PCB concentration than that of the surrounding soil and also a difference in the fingerprint of some single PCB compounds. Earthworms display a selective accumulation of cadmium and zinc in their tissues and gut content.

  5. First evidence for the presence of efflux pump in the earthworm Eisenia andrei.

    PubMed

    Hackenberger, Branimir K; Velki, Mirna; Stepić, Sandra; Hackenberger, Davorka K

    2012-01-01

    Efflux pumps are transport proteins involved in the extrusion of toxic substrates from cells to the external environment. Activities of efflux pumps have been found in many organisms, however such activity has not been evidenced in earthworms. Adult Eisenia andrei earthworms were exposed to efflux modulators - verapamil (a known inhibitor of efflux pump protein) and dexamethasone (a known inducer of efflux activity) - and the amount of absorbed fluorescent dye rhodamine B was measured. The results showed that verapamil inhibited efflux activity and decreased removal of rhodamine B, whereas dexamethasone induced efflux activity and increased removal of rhodamine B. This is the first evidence of the presence of efflux pump in earthworm Eisenia andrei. Since earthworms are often used as test organisms due to their sensitive reactions towards environmental influences, the discovery of efflux pump activity can contribute to the better understanding of toxicity of certain pollutants. PMID:22033226

  6. Vermistabilization of sugar beet (Beta vulgaris L) waste produced from sugar factory using earthworm Eisenia fetida: Genotoxic assessment by Allium cepa test.

    PubMed

    Bhat, Sartaj Ahmad; Singh, Jaswinder; Vig, Adarsh Pal

    2015-08-01

    In the present study, sugar beet mud (SBM) and pulp (SBP) produced as a waste by-products of the sugar industry were mixed with cattle dung (CD) at different ratios on dry weight basis for vermicomposting with Eisenia fetida. Minimum mortality and highest population of worms were observed in 20:80 (SBM20) mixture of SBM and 10:90 (SBP10) ratios. However, increased percentages of wastes significantly affected the growth and fecundity of worms. Nutrients like nitrogen, phosphorus, sodium, increased from initial feed mixture to final products (i.e., vermicompost), while organic carbon (OC), C:N ratio and electrical conductivity (EC) declined in all the products of vermicomposting. Although there was an increase in the contents of all the heavy metals except copper, chromium, and iron in SBM, the contents were less than the international standards for compost which indicates that the vermicompost can be used in the fields without any ill effects on the soil. Allium cepa root chromosomal aberration assay was used to evaluate the genotoxicity of pre- and post-vermicomposted SBM to understand the effect of vermicomposting on the reduction of toxicity. Genotoxicity analysis of post-vermicomposted samples of SBM revealed 18-75% decline in the aberration frequencies. Scanning electron microscopy (SEM) was recorded to identify the changes in texture in the control and vermicomposted samples. The vermicomposted mixtures in the presence of earthworms confirm more numerous surface irregularities that prove to be good manure. PMID:25794577

  7. Do alterations in mesofauna community affect earthworms?

    PubMed

    Uvarov, Alexei V; Karaban, Kamil

    2015-11-01

    Interactions between the saprotrophic animal groups that strongly control soil microbial activities and the functioning of detrital food webs, such as earthworms and mesofauna, are not well understood. Earthworm trophic and engineering activities strongly affect mesofauna abundance and diversity through various direct and indirect pathways. In contrast, mesofauna effects on earthworm populations are less evident; however, their importance may be high, considering the keystone significance of earthworms for the functioning of the soil system. We studied effects of a diverse mesofauna community of a deciduous forest on two earthworm species representing epigeic (Lumbricus rubellus) and endogeic (Aporrectodea caliginosa) ecological groups. In microcosms, the density of total mesofauna or its separate groups (enchytraeids, collembolans, gamasid mites) was manipulated (increased) and responses of earthworms and soil systems were recorded. A rise in mesofauna density resulted in a decrease of biomass and an increased mortality in L. rubellus, presumably due to competition with mesofauna for litter resources. In contrast, similar mesofauna manipulations promoted reproduction of A. caliginosa, suggesting a facilitated exploitation of litter resources due to increased mesofauna activities. Changes of microcosm respiration rates, litter organic matter content and microbial activities across the manipulation treatments indicate that mesofauna modify responses of soil systems in the presence of earthworms. However, similar mesofauna manipulations could induce different responses in soil systems with either epigeic or endogeic lumbricids, which suggests that earthworm/mesofauna interactions are species-specific. Thus, mesofauna impacts should be treated as a factor affecting the engineering activities of epigeic and endogeic earthworms in the soil. PMID:26188519

  8. Gut wall bacteria of earthworms: a natural selection process.

    PubMed

    Thakuria, Dwipendra; Schmidt, Olaf; Finan, Dillon; Egan, Damian; Doohan, Fiona M

    2010-03-01

    Earthworms and microorganisms are interdependent and their interactions regulate the biogeochemistry of terrestrial soils. Investigating earthworm-microorganism interactions, we tested the hypothesis that differences in burrowing and feeding habits of anecic and endogeic earthworms are reflected by the existence of ecological group-specific gut wall bacterial communities. Bacterial community was detected using automated ribosomal intergenic spacer analysis of 16S and 23S genes and ribotype data was used to assess diversity and community composition. Using soil and earthworm samples collected from adjacent wheat-barley and grass-clover fields, we found that the anecic Lumbricus terrestris and L. friendi, the endogeic Aporrectodea caliginosa and A. longa (classically defined as anecic, but now known to possess endogeic characteristics) contain ecological group-specific gut wall-associated bacterial communities. The abundance of specific gut wall-associated bacteria (identified by sequence analysis of ribotype bands), including Proteobacteria, Firmicutes and an actinobacterium, was ecological group dependent. A microcosm study, conducted using A. caliginosa and L. terrestris and five different feeding regimes, indicated that food resource can cause shifts in gut wall-associated bacterial community, but the magnitude of these shifts did not obscure the delineation between ecological group specificity. Using A. caliginosa and A. longa samples collected in six different arable fields, we deduced that, within an ecological group, habitat was a more important determinant of gut wall-associated bacterial community composition than was host species. Hence, we conclude that the selection of bacteria associated with the gut wall of earthworms is a natural selection process and the strongest determinant of this process is in the order ecological group>habitat>species. PMID:19924156

  9. Comparative toxicity and bioaccumulation of fenvalerate and esfenvalerate to earthworm Eisenia fetida.

    PubMed

    Ye, Xiaoqing; Xiong, Kang; Liu, Jing

    2016-06-01

    More attention is being paid to the enantioselective toxicity of chiral pesticides. However, limited investigations have been done to assess the ecological risks of chiral pesticides to soil community. Fenvalerate (FV), an extensively used synthetic pyrethroid, is a typical chiral pesticide. The most insecticidally active enantiomer of FV, esfenvalerate (ESFV), also has been marketed and widely used. In this study, the toxicological sensitivity and bioaccumulation of FV and ESFV in earthworms were assessed. The results showed that FV was less toxic than ESFV, but more accumulated in earthworms. ESFV was at least 4 times more toxic to earthworms than FV according to the filter paper contact toxicity test and the artificial soil test. Enantiospecific induction in oxidative stress was observed in earthworms exposed to FV and ESFV. The bioaccumulation of FV and ESFV in earthworm tissues was also enantioselective, preferentially accumulating FV. The uptake of ESFV by earthworms was lower than that of FV, so that the biota to soil accumulation factor (BSAF) value of ESFV was lower than that of FV. Our findings suggest that the enantioselective toxicity and bioaccumulation of chiral pesticides should be considered for evaluating ecological risks of these compounds to non-target organisms. PMID:26900980

  10. The Effects of Social Anxiety and State Anxiety on Visual Attention: Testing the Vigilance-Avoidance Hypothesis.

    PubMed

    Singh, J Suzanne; Capozzoli, Michelle C; Dodd, Michael D; Hope, Debra A

    2015-01-01

    A growing theoretical and research literature suggests that trait and state social anxiety can predict attentional patterns in the presence of emotional stimuli. The current study adds to this literature by examining the effects of state anxiety on visual attention and testing the vigilance-avoidance hypothesis, using a method of continuous visual attentional assessment. Participants were 91 undergraduate college students with high or low trait fear of negative evaluation (FNE), a core aspect of social anxiety, who were randomly assigned to either a high or low state anxiety condition. Participants engaged in a free view task in which pairs of emotional facial stimuli were presented and eye movements were continuously monitored. Overall, participants with high FNE avoided angry stimuli and participants with high state anxiety attended to positive stimuli. Participants with high state anxiety and high FNE were avoidant of angry faces, whereas participants with low state and low FNE exhibited a bias toward angry faces. The study provided partial support for the vigilance-avoidance hypothesis. The findings add to the mixed results in the literature that suggest that both positive and negative emotional stimuli may be important in understanding the complex attention patterns associated with social anxiety. Clinical implications and suggestions for future research are discussed. PMID:25767901

  11. Numerical test of Flory formulas for true self-avoiding walks on fractal lattices

    NASA Astrophysics Data System (ADS)

    Lee, Sang Bub

    1992-05-01

    We review the Flory-type formulas for true self-avoiding walks (TSAW's) on fractal substrates proposed by Rammal [J. Stat. Phys. 36, 547 (1984)] and by Bouchaud and Georges [Phys. Rev. B 39, 2846 (1989)] and present a formula obtained by simple Flory approximation. We also present the Monte Carlo data for TSAW's on a Sierpinski gasket embedded in both two and three dimensions and on a percolation backbone at the percolation threshold in two dimensions. The previous data on an infinite percolation cluster and our present data suggest that all known formulas describe fairly well the critical behavior of TSAW's on fractals; however, that by Bouchaud and Georges and our formula show better agreement.

  12. Litter effects on seedling establishment interact with seed position and earthworm activity.

    PubMed

    Donath, T W; Eckstein, R L

    2012-01-01

    Seedling establishment is influenced by litter cover and by seed predators, but little is known about interactions between these two factors. We tested their effects on emergence of five typical grassland species in a microcosm experiment. We manipulated the amounts of grass litter, seed sowing position and earthworm activity to determine whether: (i) the protective effect of litter against seed predation depends on cover amount and seed sowing position, i.e., on top or beneath litter; (ii) seed transport by earthworms changes the effect of seed sowing position on seedling emergence; and (iii) seeds transported into deeper soil layers by earthworms are still germinable. Litter cover and presence of earthworms lowered seedling emergence. The impact of seed position increased with seed size. Emergence of large-seeded species was reduced when sown on the surface. Additionally, we found an important seed position × earthworm interaction related to seed size. Emergence of large-seeded species sown on top of the litter was up to three times higher when earthworms were present than without earthworms. Earthworms also significantly altered the depth distribution of seeds in the soil and across treatments: on average 6% of seeds germinated after burial. In contrast to the seed position effect, we found no size effect on mobility and germinability of seeds after burial in the soil. Nevertheless, the fate of different-sized seeds may differ. While burial will remove large seeds from the regeneration pool, it may enhance seed bank build up in small-seeded species. Consequently, changes in the amount of litter cover and the invertebrate community play a significant role in plant community composition. PMID:21972886

  13. Approach-Avoidance Motivational Profiles in Early Adolescents to the PACER Fitness Test

    ERIC Educational Resources Information Center

    Garn, Alex; Sun, Haichun

    2009-01-01

    The use of fitness testing is a practical means for measuring components of health-related fitness, but there is currently substantial debate over the motivating effects of these tests. Therefore, the purpose of this study was to examine the cross-fertilization of achievement and friendship goal profiles for early adolescents involved in the…

  14. EARTHWORMS AND THEIR IMPACT ON SLUG CONTROL

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increases in the anecic earthworm species, Lumbricus terrestris L., have occurred in western Oregon grass fields due to increases in surface residue since the phase-out of open field burning. The use of earthworm toxic chemicals has been reduced through concerns for other important vertebrate and in...

  15. Arsenic biotransformation in earthworms from contaminated soils.

    PubMed

    Button, Mark; Jenkin, Gawen R T; Harrington, Chris F; Watts, Michael J

    2009-08-01

    Two species of arsenic (As) resistant earthworm, Lumbricus rubellus and Dendrodrillus rubidus, their host soils and soil excretions (casts) were collected from 23 locations at a former As mine in Devon, UK. Total As concentrations, measured by ICP-MS, ranged from 255 to 13,080 mg kg(-1) in soils, 11 to 877 mg kg(-1) in earthworms and 284 to 4221 mg kg(-1) in earthworm casts from a sub-sample of 10 of the 23 investigated sites. The samples were also measured for As speciation using HPLC-ICP-MS to investigate potential As biotransformation pathways. Inorganic arsenate (As(V)) and arsenite (As(III)) were the only species detected in the soil. As(V) and As(III) were also the dominant species found in the earthworms and cast material together with lower proportions of the organic species methylarsonate (MA(V)), dimethylarsinate (DMA(V)), arsenobetaine (AB) and three arsenosugars. Whilst the inorganic As content of the earthworms increased with increasing As body burden, the concentration of organic species remained relatively constant. These results suggest that the biotransformation of inorganic arsenic to organic species does not contribute to As resistance in the sampled earthworm populations. Quantification of As speciation in the soil, earthworms and cast material allows a more comprehensive pathway for the formation of AB in earthworms to be elucidated. PMID:19657532

  16. A series test of the scaling limit of self-avoiding walks

    NASA Astrophysics Data System (ADS)

    Guttmann, Anthony J.; Jacobsen, Jesper L.

    2013-11-01

    It is widely believed that the scaling limit of self-avoiding walks (SAWs) at the critical temperature is conformally invariant, and consequently describable by Schramm-Loewner evolution with parameter κ = 8/3. We consider SAWs in a rectangle, which originate at its centre and end at the boundary. We assume that the boundary density transforms covariantly in a way that depends precisely on κ, as conjectured by Lawler, Schramm and Werner (2004 Fractal Geometry and Applications: A Jubilee of Benoit Mandelbrot part 2, pp 339-64). It has previously been shown by Guttmann and Kennedy (2013 J. Eng. Math. at press) that, in the limit of an infinitely large rectangle, the ratio of the fraction of SAWs hitting the side of the rectangle to the fraction that hit the end of the rectangle can be calculated. By considering rectangles of fixed aspect ratio 2, and also rectangles of aspect ratio 10, we calculate this ratio exactly for larger and larger rectangles. By extrapolating this data to infinite rectangle size, and invoking the above conjectures, we obtain the estimate κ = 2.666 64 ± 0.000 07 for rectangles of aspect ratio 2 and κ = 2.666 75 ± 0.000 15 for rectangles of aspect ratio 10. We also provide numerical evidence supporting the conjectured distribution of SAWs striking the boundary at various points in the case of rectangles with aspect ratio 2.

  17. Holography: Use in Training and Testing Drivers on the Road in Accident Avoidance.

    ERIC Educational Resources Information Center

    Frey, Allan H.; Frey, Donnalyn

    1979-01-01

    Defines holography, identifies visual factors in driving and the techniques used in on-road visual presentations, and presents the design and testing of a holographic system for driver training. (RAO)

  18. Helicopter Field Testing of NASA's Autonomous Landing and Hazard Avoidance Technology (ALHAT) System fully Integrated with the Morpheus Vertical Test Bed Avionics

    NASA Technical Reports Server (NTRS)

    Epp, Chirold D.; Robertson, Edward A.; Ruthishauser, David K.

    2013-01-01

    The Autonomous Landing and Hazard Avoidance Technology (ALHAT) Project was chartered to develop and mature to a Technology Readiness Level (TRL) of six an autonomous system combining guidance, navigation and control with real-time terrain sensing and recognition functions for crewed, cargo, and robotic planetary landing vehicles. The ALHAT System must be capable of identifying and avoiding surface hazards to enable a safe and accurate landing to within tens of meters of designated and certified landing sites anywhere on a planetary surface under any lighting conditions. This is accomplished with the core sensing functions of the ALHAT system: Terrain Relative Navigation (TRN), Hazard Detection and Avoidance (HDA), and Hazard Relative Navigation (HRN). The NASA plan for the ALHAT technology is to perform the TRL6 closed loop demonstration on the Morpheus Vertical Test Bed (VTB). The first Morpheus vehicle was lost in August of 2012 during free-flight testing at Kennedy Space Center (KSC), so the decision was made to perform a helicopter test of the integrated ALHAT System with the Morpheus avionics over the ALHAT planetary hazard field at KSC. The KSC helicopter tests included flight profiles approximating planetary approaches, with the entire ALHAT system interfaced with all appropriate Morpheus subsystems and operated in real-time. During these helicopter flights, the ALHAT system imaged the simulated lunar terrain constructed in FY2012 to support ALHAT/Morpheus testing at KSC. To the best of our knowledge, this represents the highest fidelity testing of a system of this kind to date. During this helicopter testing, two new Morpheus landers were under construction at the Johnson Space Center to support the objective of an integrated ALHAT/Morpheus free-flight demonstration. This paper provides an overview of this helicopter flight test activity, including results and lessons learned, and also provides an overview of recent integrated testing of ALHAT on the second

  19. Helicopter Field Testing of NASA's Autonomous Landing and Hazard Avoidance Technology (ALHAT) System fully integrated with the Morpheus Vertical Test Bed Avionics

    NASA Technical Reports Server (NTRS)

    Rutishauser, David; Epp, Chirold; Robertson, Edward

    2013-01-01

    The Autonomous Landing Hazard Avoidance Technology (ALHAT) Project was chartered to develop and mature to a Technology Readiness Level (TRL) of six an autonomous system combining guidance, navigation and control with real-time terrain sensing and recognition functions for crewed, cargo, and robotic planetary landing vehicles. The ALHAT System must be capable of identifying and avoiding surface hazards to enable a safe and accurate landing to within tens of meters of designated and certified landing sites anywhere on a planetary surface under any lighting conditions. This is accomplished with the core sensing functions of the ALHAT system: Terrain Relative Navigation (TRN), Hazard Detection and Avoidance (HDA), and Hazard Relative Navigation (HRN). The NASA plan for the ALHAT technology is to perform the TRL6 closed loop demonstration on the Morpheus Vertical Test Bed (VTB). The first Morpheus vehicle was lost in August of 2012 during free-flight testing at Kennedy Space Center (KSC), so the decision was made to perform a helicopter test of the integrated ALHAT System with the Morpheus avionics over the ALHAT planetary hazard field at KSC. The KSC helicopter tests included flight profiles approximating planetary approaches, with the entire ALHAT system interfaced with all appropriate Morpheus subsystems and operated in real-time. During these helicopter flights, the ALHAT system imaged the simulated lunar terrain constructed in FY2012 to support ALHAT/Morpheus testing at KSC. To the best of our knowledge, this represents the highest fidelity testing of a system of this kind to date. During this helicopter testing, two new Morpheus landers were under construction at the Johnson Space Center to support the objective of an integrated ALHAT/Morpheus free-flight demonstration. This paper provides an overview of this helicopter flight test activity, including results and lessons learned, and also provides an overview of recent integrated testing of ALHAT on the second

  20. Survival, growth, detoxifying and antioxidative responses of earthworms (Eisenia fetida) exposed to soils with industrial DDT contamination.

    PubMed

    Shi, Yajuan; Zhang, Qiangbin; Huang, Dunqi; Zheng, Xiaoqi; Shi, Yajing

    2016-03-01

    The survival, growth, activity of the biotransformation system phase II enzyme glutathione-S-transferase (GST) and the oxidative defense enzyme catalase (CAT) of earthworms exposed to the contaminated soils from a former DDT plant and reference soils were investigated, and compared with the corresponding indicators in simulated soil-earthworm system, unpolluted natural soils with spiked-in DDT series, to identify the toxic effects of DDT on earthworms and their cellular defense system in complex soil system. The results indicated that DDT level in the contaminated soils was significantly higher than that in the reference soils with similar level of other pollutants and soil characters. The mortality, growth inhibition rates, GST and CST activities of earthworms exposed to the contaminated soils were significantly higher than that in reference soils. The contribution of historical DDT in contaminated soils to earthworms was confirmed by the DDT spiked tests. DDT spiked in soils at rates of higher than 200 mg·kg(-1) was significantly toxic to both the survival and the growth of earthworms. DDT significantly stimulated GST and CAT activity in earthworms after 14 days. The CAT and GST activities were also stimulated by DDT exposure at rates of 100 mg·kg(-1) after chronic exposure (42 days). The results provide implications for validating the extrapolation from laboratory simulated soils criteria to contaminated soils and for making site risk assessments. PMID:26969436

  1. Galaxy cluster collision speeds as a test of LCDM: possible systematics & how to avoid them

    NASA Astrophysics Data System (ADS)

    Banik, Indranil; Zhao, Hongsheng

    2016-05-01

    The formation of structure may have been more efficient than expected in the concordance LCDM model. This is suggested by the early formation of the El Gordo cluster, but perhaps even more so by the high collision velocity of the two components of the Bullet Cluster. Unfortunately, the collision is mostly within the plane of the sky. With proper motions near-impossible to observe at z = 0.3, the collision speed estimate comes from modelling of the shock created in the gas by the collision. Also important is the separation of the gas and dark matter, inferred from comparing X-ray images with weak gravitational lensing maps. I will describe how the collision speed may be measured directly using the Moving Cluster Effect (MCE). This is based on the time-dependent potential of the cluster making double images of a background galaxy have different redshifts. I'll also explain some of the systematics that may affect such a measurement and some strategies that may reduce these. Measurements using the MCE may allow a much more reliable test of LCDM based on how often such fast collisions between galaxy clusters actually occur. More info: MNRAS, vol 450, page 3155

  2. Biotic interactions modify the transfer of cesium-137 in a soil-earthworm-plant-snail food web.

    PubMed

    Fritsch, Clémentine; Scheifler, Renaud; Beaugelin-Seiller, Karine; Hubert, Philippe; Coeurdassier, Michaël; de Vaufleury, Annette; Badot, Pierre-Marie

    2008-08-01

    The present study investigated the possible influence of the earthworm Aporrectodea tuberculata on the transfer of cesium-137 ((137)Cs) from a contaminated (130 Bq/kg) deciduous forest soil to the lettuce Lactuca sativa and to the snail Cantareus aspersus (formerly Helix aspersa) in two laboratory experiments. In the first experiment, the International Organization for Standardization 15952 test was used to expose snails for five weeks to contaminated soil with or without earthworms. In these conditions, the presence of earthworms caused a two- to threefold increase in (137)Cs concentrations in snails. Transfer was low in earthworms as well as in snails, with transfer factors (TFs) lower than 3.7 x 10(-2). Activity concentrations were higher in earthworms (2.8- 4.8 Bq/kg dry mass) than in snails (<1.5 Bq/kg). In the second experiment, microcosms were used to determine the contribution of soil and lettuce in the accumulation of (137)Cs in snails. Results suggest that the contribution of lettuce and soil is 80 and 20%, respectively. Microcosms also were used to study the influence of earthworms on (137)Cs accumulation in snail tissues in the most ecologically relevant treatment (soil-earthworm-plant-snail food web). In this case, soil-to-plant transfer was high, with a TF of 0.8, and was not significantly modified by earthworms. Conversely, soil-to-snail transfer was lower (TF, approximately 0.1) but was significantly increased in presence of earthworms. Dose rates were determined in the microcosm study with the EDEN (elementary dose evaluation for natural environment) model. Dose rates were lower than 5.5 x 10(-4) mGy/d, far from values considered to have effects on terrestrial organisms (1 mGy/d). PMID:18266477

  3. Acute and sublethal effects of sequential exposure to the pesticide azinphos-methyl on juvenile earthworms (Eisenia andrei).

    PubMed

    Jordaan, Martine S; Reinecke, Sophié A; Reinecke, Adriaan J

    2012-04-01

    The use of organophosphate pesticides is an integral part of commercial farming activities and these substances have been implicated as a major source of environmental contamination and may impact on a range of non-target fauna. The extent to which soil dwelling non-target organisms are affected by exposure to the organophosphate azinphos-methyl was investigated through monitoring selected biomarker responses and life cycle effects under laboratory conditions in the earthworm Eisenia andrei. Standard acute toxicity tests were conducted followed by a sequential exposure regime experiment, in order to assess the effects of multiple pesticide applications on biomarker (cholinesterase activity and neutral red retention time), life-cycle (growth and reproduction) and behaviour (avoidance and burrowing activity) responses. The present study indicates that the time between exposure events was a more important variable than concentration and that a longer interval between exposures may mitigate the effects of pesticide exposure provided that the exposure concentration is low. Additionally, it was shown that E. andrei was unable to avoid the presence of azinphos-methyl in soil, even at concentrations as high as 50% of the LC(50) value, indicating that the presence of azinphos-methyl in the soil pose a realistic threat to earthworms and other soil dwelling organisms. The ChE inhibition test showed a high percentage inhibition of the enzyme in all exposure groups that survived and NRR times of exposed organisms were lower than that of the controls. The present study yielded important results that contribute to the understanding of biological impacts of pesticide pollution on the environment. Extrapolating these results can aid in optimising pesticide application regimes to mitigate the environmental effects thereof and thus ensuring sustained soil biodiversity in agricultural areas. PMID:22086221

  4. COMPARISON OF THREE EARTHWORM BIOASSAY PROCEDURES FOR THE ASSESSMENT OF ENVIRONMENTAL SAMPLES CONTAINING HAZARDOUS WASTES

    EPA Science Inventory

    Three different laboratory earthworm protocols for assessing the potential toxicity of environmental samples were evaluated using Eisenia fetida. The 48-h Contact Test (CT) is a short test and may indicate the presence of water-soluble chemicals. The 14-day Soil Test (ST) is best...

  5. Plant genetic variation mediates an indirect ecological effect between belowground earthworms and aboveground aphids

    PubMed Central

    2014-01-01

    Background Interactions between aboveground and belowground terrestrial communities are often mediated by plants, with soil organisms interacting via the roots and aboveground organisms via the shoots and leaves. Many studies now show that plant genetics can drive changes in the structure of both above and belowground communities; however, the role of plant genetic variation in mediating aboveground-belowground interactions is still unclear. We used an earthworm-plant-aphid model system with two aphid species (Aphis fabae and Acyrthosiphon pisum) to test the effect of host-plant (Vicia faba) genetic variation on the indirect interaction between the belowground earthworms (Eisenia veneta) on the aboveground aphid populations. Results Our data shows that host-plant variety mediated an indirect ecological effect of earthworms on generalist black bean aphids (A. fabae), with earthworms increasing aphid growth rate in three plant varieties but decreasing it in another variety. We found no effect of earthworms on the second aphid species, the pea aphid (A. pisum), and no effect of competition between the aphid species. Plant biomass was increased when earthworms were present, and decreased when A. pisum was feeding on the plant (mediated by plant variety). Although A. fabae aphids were influenced by the plants and worms, they did not, in turn, alter plant biomass. Conclusions Previous work has shown inconsistent effects of earthworms on aphids, but we suggest these differences could be explained by plant genetic variation and variation among aphid species. This study demonstrates that the outcome of belowground-aboveground interactions can be mediated by genetic variation in the host-plant, but depends on the identity of the species involved. PMID:25331082

  6. Epigeic Earthworms Exert a Bottleneck Effect on Microbial Communities through Gut Associated Processes

    PubMed Central

    Gómez-Brandón, María; Aira, Manuel; Lores, Marta; Domínguez, Jorge

    2011-01-01

    Background Earthworms play a critical role in organic matter decomposition because of the interactions they establish with microorganisms. The ingestion, digestion, assimilation of organic material in the gut and then casting is the first step in earthworm-microorganism interactions. The current knowledge of these direct effects is still limited for epigeic earthworm species, mainly those living in man-made environments. Here we tested whether and to what extent the earthworm Eisenia andrei is capable of altering the microbiological properties of fresh organic matter through gut associated processes; and if these direct effects are related to the earthworm diet. Methodology To address these questions we determined the microbial community structure (phospholipid fatty acid profiles) and microbial activity (fluorescein diacetate hydrolysis) in the earthworm casts derived from three types of animal manure (cow, horse and pig manure), which differed in microbial composition. Principal Findings The passage of the organic material through the gut of E. andrei reduced the total microbial biomass irrespective of the type of manure, and resulted in a decrease in bacterial biomass in all the manures; whilst leaving the fungi unaffected in the egested materials. However, unlike the microbial biomass, no such reduction was detected in the total microbial activity of cast samples derived from the pig manure. Moreover, no differences were found between cast samples derived from the different types of manure with regards to microbial community structure, which provides strong evidence for a bottleneck effect of worm digestion on microbial populations of the original material consumed. Conclusions/Significance Our data reveal that earthworm gut is a major shaper of microbial communities, thereby favouring the existence of a reduced but more active microbial population in the egested materials, which is of great importance to understand how biotic interactions within the decomposer

  7. Fifteen new earthworm mitogenomes shed new light on phylogeny within the Pheretima complex

    PubMed Central

    Zhang, Liangliang; Sechi, Pierfrancesco; Yuan, Minglong; Jiang, Jibao; Dong, Yan; Qiu, Jiangping

    2016-01-01

    The Pheretima complex within the Megascolecidae family is a major earthworm group. Recently, the systematic status of the Pheretima complex based on morphology was challenged by molecular studies. In this study, we carry out the first comparative mitogenomic study in oligochaetes. The mitogenomes of 15 earthworm species were sequenced and compared with other 9 available earthworm mitogenomes, with the main aim to explore their phylogenetic relationships and test different analytical approaches on phylogeny reconstruction. The general earthworm mitogenomic features revealed to be conservative: all genes encoded on the same strand, all the protein coding loci shared the same initiation codon (ATG), and tRNA genes showed conserved structures. The Drawida japonica mitogenome displayed the highest A + T content, reversed AT/GC-skews and the highest genetic diversity. Genetic distances among protein coding genes displayed their maximum and minimum interspecific values in the ATP8 and CO1 genes, respectively. The 22 tRNAs showed variable substitution patterns between the considered earthworm mitogenomes. The inclusion of rRNAs positively increased phylogenetic support. Furthermore, we tested different trimming tools for alignment improvement. Our analyses rejected reciprocal monophyly among Amynthas and Metaphire and indicated that the two genera should be systematically classified into one. PMID:26833286

  8. Effects of non-native earthworms on on below- and aboveground processes in the Mid-Atlantic region

    NASA Astrophysics Data System (ADS)

    Szlavecz, K. A.; McCormick, M. K.; Xia, L.; Pitz, S.; O'Neill, J.; Bernard, M.; Chang, C.; Whigham, D. F.

    2011-12-01

    Many biotic and abiotic disturbances have shaped the structure of the deciduous forests in the Mid-Atlantic region. One major anthropogenic factor is land use history. Agricultural practices in the past undoubtedly facilitated non-native earthworm colonization and establishment. Today most secondary forests are dominated by European lumbricid earthworms, although native species also occur in some habitats. To investigate how earthworm community composition and abundance affect belowground processes and tree seedling growth we set up a field manipulation experiment at the Smithsonian Environmental Research Center in Edgewater, MD. A total of 66 experimental plots were set up in successional (70 yrs) and mature (150 yrs) Tulip-poplar-Oak associations. We manipulated earthworm abundance and leaf litter input, and planted seedlings of Tulip poplar, Red maple, Red oak, and American beech. The experiment lasted for two years during which we regularly monitored density, biomass and species composition of earthworm assemblages and measured soil respiration. Soil moisture, temperature and air temperature were also continuously monitored using a wireless sensor network. At harvest, soil bulk density, pH, N pools, C:N ratio, potential N-mineralization rates, and enzyme activity were determined. We used quantitative PCR to assess the community composition of soil fungi. We also determined the extent of mycorrhizal colonization and biomass of roots, shoots and leaves. We conducted likelihood ratio tests for random and fixed effects based on mixed model analyses of variance. Differences between soil depths and among sites and plots accounted for a large portion of the variation in many soil properties. Litter quality affected soil pH and N mineralization. Earthworm densities affected bulk density, inorganic N content, and N mineralization. Both mycorrhizal groups were more abundant in mature than in successional forests. Both ectomycorrhizal (ECM) and arbuscular (AM) fungi were

  9. Comparative toxicity of chemicals to earthworms

    SciTech Connect

    Callahan, C.A.; Shirazi, M.A. ); Neuhauser, E.F. )

    1994-02-01

    The concentration-response (mortality) relationships of four species of earthworms, Eisenia fetida (Savigny), Allolobophora tuberculata (Eisen), Eudrilus eugeniae (Kinberg), and Perionyx excavatus (Perrier) are summarized for 62 chemicals and two test protocols. A Weibull function is used to summarize these data for each chemical in terms of sensitivity and toxicity, in addition to the LC50. The estimation of the Weibull parameters a and k summarize the entire concentration-response relationship. This technique should be applicable to a variety of testing protocols with different species whenever the goal is summarizing the shape of the concentration-response curves to fully evaluate chemical impact on organisms. In some cases for these data four orders of magnitude separate LC50s of the soil test and the contact test for the same chemical and species. All four species appear to be similar in range of toxicity and tolerance to these chemicals, suggesting that Eisenia fetida and may be representative of these four species and these chemicals.

  10. Unique metabolites protect earthworms against plant polyphenols

    PubMed Central

    Liebeke, Manuel; Strittmatter, Nicole; Fearn, Sarah; Morgan, A. John; Kille, Peter; Fuchser, Jens; Wallis, David; Palchykov, Vitalii; Robertson, Jeremy; Lahive, Elma; Spurgeon, David J.; McPhail, David; Takáts, Zoltán; Bundy, Jacob G.

    2015-01-01

    All higher plants produce polyphenols, for defence against above-ground herbivory. These polyphenols also influence the soil micro- and macro-fauna that break down plant leaf litter. Polyphenols therefore indirectly affect the fluxes of soil nutrients and, ultimately, carbon turnover and ecosystem functioning in soils. It is unknown how earthworms, the major component of animal biomass in many soils, cope with high-polyphenol diets. Here, we show that earthworms possess a class of unique surface-active metabolites in their gut, which we term ‘drilodefensins'. These compounds counteract the inhibitory effects of polyphenols on earthworm gut enzymes, and high-polyphenol diets increase drilodefensin concentrations in both laboratory and field populations. This shows that drilodefensins protect earthworms from the harmful effects of ingested polyphenols. We have identified the key mechanism for adaptation to a dietary challenge in an animal group that has a major role in organic matter recycling in soils worldwide. PMID:26241769

  11. Unique metabolites protect earthworms against plant polyphenols.

    PubMed

    Liebeke, Manuel; Strittmatter, Nicole; Fearn, Sarah; Morgan, A John; Kille, Peter; Fuchser, Jens; Wallis, David; Palchykov, Vitalii; Robertson, Jeremy; Lahive, Elma; Spurgeon, David J; McPhail, David; Takáts, Zoltán; Bundy, Jacob G

    2015-01-01

    All higher plants produce polyphenols, for defence against above-ground herbivory. These polyphenols also influence the soil micro- and macro-fauna that break down plant leaf litter. Polyphenols therefore indirectly affect the fluxes of soil nutrients and, ultimately, carbon turnover and ecosystem functioning in soils. It is unknown how earthworms, the major component of animal biomass in many soils, cope with high-polyphenol diets. Here, we show that earthworms possess a class of unique surface-active metabolites in their gut, which we term 'drilodefensins'. These compounds counteract the inhibitory effects of polyphenols on earthworm gut enzymes, and high-polyphenol diets increase drilodefensin concentrations in both laboratory and field populations. This shows that drilodefensins protect earthworms from the harmful effects of ingested polyphenols. We have identified the key mechanism for adaptation to a dietary challenge in an animal group that has a major role in organic matter recycling in soils worldwide. PMID:26241769

  12. Nanomaterials: Earthworms lit with quantum dots

    NASA Astrophysics Data System (ADS)

    Tilley, Richard D.; Cheong, Soshan

    2013-01-01

    Yeast, bacteria and fungi have been used to synthesize a variety of nanocrystals. Now, the metal detoxification process in the gut of an earthworm is exploited to produce biocompatible cadmium telluride quantum dots.

  13. Metal accumulation in earthworms inhabiting floodplain soils.

    PubMed

    Vijver, Martina G; Vink, Jos P M; Miermans, Cornelis J H; van Gestel, Cornelis A M

    2007-07-01

    The main factors contributing to variation in metal concentrations in earthworms inhabiting floodplain soils were investigated in three floodplains differing in inundation frequency and vegetation type. Metal concentrations in epigeic earthworms showed larger seasonal variations than endogeic earthworms. Variation in internal levels between sampling intervals were largest in earthworms from floodplain sites frequently inundated. High and low frequency flooding did not result in consistent changes in internal metal concentrations. Vegetation types of the floodplains did not affect metal levels in Lumbricus rubellus, except for internal Cd levels, which were positively related to the presence of organic litter. Internal levels of most essential metals were higher in spring. In general, no clear patterns in metal uptake were found and repetition of the sampling campaign will probably yield different results. PMID:17254683

  14. Individual and combined toxic effects of cypermethrin and chlorpyrifos on earthworm.

    PubMed

    Zhou, Shiping; Duan, Changqun; Michelle, Wong Hang Gi; Yang, Fazhong; Wang, Xuehua

    2011-01-01

    Toxicities were assessed for a pyrethroid (cypermethrin) and an organophosphate insecticide (chlorpyrifos) individually and in combination. A series of tests were conducted on different responses (acute, chronic, behavioral) of earthworms of species Eisenia fetida andrei in the ecological risk assessment of these pesticides. The results showed that the toxicity of the mixture of cypermethrin and chlorpyrifos was significantly higher than either of these pesticides individually, especially on the earthworm's chronic responses. At a concentration of 5 mg/kg, the mixture caused significant reductions on the growth and reproduction rates of earthworms, but did not cause any significant effect when the individual was tested. The increase in toxicity of the pesticide mixture means that the use of toxicity data obtained exclusively from single-pesticide experiments may underestimate the ecological risk of pesticides that actually present in the field. PMID:21793412

  15. Bioavailability and influence of ¹⁴C-carbofuran on Eisenia andrei avoidance, growth and reproduction in treated natural tropical soils.

    PubMed

    Ferreira, Regina C B; Papini, Solange; de Andréa, Mara M

    2015-01-01

    The bioavailability of carbofuran to the compost worms Eisenia andrei and the influence of its residual amounts on the avoidance, reproduction and growth of this species were studied in two natural tropical soils: a Typic Humaquept (GM) and a Typic Hapludox (LVD), as indicated by the Brazilian environmental authorities for ecotoxicological tests. The worms avoided the soil LVD treated with different doses of carbofuran. The pesticide also affected the production of juvenile specimens in both soils, but cocoon production was reduced only in the GM soil. The earthworms' growth and weight loss were affected by carbofuran (2,2-dimethyl-2,3-dihydro-1-1-benzofuran-7-yl methylcarbamate. CAS number 1563-66-2) only in the LVD and the mortality detected at 56 days of contact with the treated soils was not statistically significant in both of them. Fourteen days after the soil treatment with(14) c-carbofuran, most residues detected in the soils were bound residues (approximately 36% and 30% in the GM and LVD, respectively) and neither mortality nor bioaccumulation was detected in the earthworms, even with absorptions of 13% and 43%, respectively. The LVD soil has lower organic matter content, and the effects of carbofuran on different aspects of the earthworms' life were more pronounced in this soil, most likely due to the higher bioavailability of the pesticide in the soil solution. The results for carbofuran clearly demonstrate that even small quantities of residues do not assure lack of toxicity. They also make evident the necessity of studying the effects of pesticides in natural agricultural soils. Furthermore, as the bound residues and the earthworm contamination are not detected by conventional techniques, they are not taken into account and may be underestimated on environmental risk assessments. PMID:25714458

  16. Copper avoidance and mortality of juvenile brown trout (Salmo trutta) in tests with copper-sulfate-treated water from West Branch Reservoir, Putnam County, New York

    USGS Publications Warehouse

    Baldigo, Barry P.; Baudanza, T.P.

    2001-01-01

    Copper-avoidance tests and acute-toxicity (mortality) tests on hatchery-reared, young-of- the-year brown trout (salmo trutta) were conducted with water from West Branch Reservoir to assess the avoidance response to copper sulfate treatment, which is used occasionally by New York City Department of Environmental Protection to decrease phytoplankton populations in the reservoir. Avoidance-test results indicate that juvenile brown trout tend to avoid dissolved copper concentrations greater than about 55 ?g/L (micrograms per liter), which is the approximate avoidance-response threshold. The mean net avoidance response of brown trout to dissolved copper concentrations of 70 and 100 ?g/L, and possibly 80 ?g/L, was significantly different (at a = 0.1) from the mean net avoidance response of fish to control (untreated) water and to treated water at most other tested concentrations. Mortality-test results indicate that the 96-hr median lethal concentration (LC50) of dissolved copper was 61.5 ?g/L. All (100 percent) of the brown trout died at a dissolved copper concentration of 85 ?g/L, many died at concentrations of 62 ?g/L and 70 ?g/L, and none died in the control waters (7 ?g/L) or at concentrations of 10, 20, or 45 ?g/L. The estimated concentration of dissolved copper that caused fish mortality (threshold) was 53.5 ?g/L, virtually equivalent to the avoidance-response threshold. Additional factors that could affect the copper-avoidance and mortality response of individual brown trout and their populations in West Branch Reservoir include seasonal variations in certain water-quality parameters, copper-treatment regimes, natural fish distributions during treatment, and increased tolerance due to acclimation. These warrant additional study before the findings from this study can be used to predict the effects that copper sulfate treatments have on resident fish populations in New York City reservoirs.

  17. Acephaline gregarine parasites (Monocystis sp.) are not transmitted sexually among their lumbricid earthworm hosts.

    PubMed

    Field, Stuart G; Michiels, Nico K

    2006-04-01

    The precise transmission mode(s) of acephaline gregarines in their earthworm hosts has long been questioned, yet a rigorous experimental evaluation of sexual transmission is currently lacking. That Monocystis sp., a common gregarine parasite of the earthworm Lumbricus terrestris, infects the sexual organs of its host is suggestive of sexual transmission. Considering the divergent evolutionary consequences of various modes of transmission, excluding or proving sexual transmission in this host-parasite system is critical to fully understanding it. We cultured uninfected earthworms from cocoons and subsequently mated them to either an infected or uninfected partner (from the wild). We then compared these individuals with an orally infected group, which were infected using a newly developed gavage (oral injection) method. Our data have unambiguously established that (1) horizontal sexual transmission does not play a significant role in the transmission of Monocystis sp., and (2) oral transmission through the soil is likely the principal mode of transmission between earthworms. This finding is important to models of mate-choice because infection avoidance does not appear to drive mating decisions. Finally, we further report a successful and relatively simple method to obtain infection-free individuals, which can subsequently be infected via oral gavage and used in empirical studies. PMID:16729685

  18. [Environmental activity of earthworms (Lumbricus terrestris L.) and the spatial organization of soil communities].

    PubMed

    Tiunov, A V; Kuznetsova, N A

    2000-01-01

    The effect of feeding and burrowing activities of anecic earthworms (Lumbricus terrestris) on abiotic characteristics of the soil, biomass and activity of soil microorganisms, and the spatial distribution of Collembola and Lumbricidae species was studied in a Iinden forest near Moscow. The results showed that organic carbon content, nitrogen content, pH, and microbial biomass and basal respiration are considerably higher around L. terrestris burrows than in the surrounding soil. The total density of springtails near the burrows was 1.6-1.7 as high as at the control sites. The most pronounced preference for earthworm burrows was observed in the species dominating in the soils of undisturbed deciduous forests (Isotomiella minor and Isotoma notabilis). The number and biomass of epigeic and endogeic earthworms also increased significantly in the zone of L. terrestris burrows. However, some springtail (Isotoma viridis, Protaphorura cf. nemorata, Lepidocyrtus lignorum) and earthworm species (Aporrectodea rosea) did not accumulate near L. terrestris burrows and even avoided them. Thus, L. terrestris activities create a mosaic of soil microhabitats, which provides for the coexistence of different microcommunities of soil organisms. PMID:11042967

  19. The second wave of earthworm invasion: soil organic matter dynamics from the stable isotope perspective

    NASA Astrophysics Data System (ADS)

    Chang, C.; Szlavecz, K. A.; Bernard, M.; Pitz, S.

    2013-12-01

    Through transformation of plant litter into soil organic matter (SOM) and translocation of ingested organic material among different soil depths, soil organisms, especially earthworms, are one of the major factors affecting SOM dynamics. In North America temperate soil, historical human activity has lead to invasion of European earthworms into habitats that were previously earthworm-free or inhabited only by native species. By consuming leaf litter and SOM, burrowing, and casting, invasive earthworms have been known for reducing the understory vegetation and leaf litter layer while increasing the thickness of organic soil, causing changes in the soil habitat and the distribution of SOM. Recently, another group of invasive earthworm, namely Amynthas from Asia, has been reported invading habitats already dominated by European species, causing a 'second wave of invasion' where the soil ecosystem, already modified by European species, is going through another transition. The mechanisms through which these functionally (ecologically) different species affect C and N transformation could be better understood by tracing the carbon and nitrogen derived from 13C- and 15N-labeled leaf litter into earthworm tissues and SOM. The objective of this study is to understand how earthworm species that differ ecologically, including the Asian Amynthas, interact with each other and how these interactions affect SOM dynamics. We hypothesized that 1) species feeding on different food resources will have different isotopic signature and their tissue 13C and 15N values will change due to facilitation or interspecific competition on food resources, and 2) the short-term fate of litter-derived carbon differs depending on the presence or absence of different earthworm species. These hypotheses were tested by field sampling and lab mesocosm experiments using 13C and 15N double-enriched Tulip Poplar leaf litter (mean 13C = 124‰, mean 15N = 1667‰) produced from tree saplings growing in an

  20. Histopathological changes in the earthworm Eisenia andrei associated with the exposure to metals and radionuclides.

    PubMed

    Lourenço, Joana; Silva, Ana; Carvalho, Fernando; Oliveira, João; Malta, Margarida; Mendo, Sónia; Gonçalves, Fernando; Pereira, Ruth

    2011-11-01

    Earthworms were exposed for 56 d to a contaminated soil, from an abandoned uranium mine, and to the natural reference soil LUFA 2.2. Histological changes in earthworm's body wall (epidermis, circular and longitudinal muscles) and gastrointestinal tract (chloragogenous tissue and intestinal epithelium) were assessed, after 0, 14 and 56 d of exposure. Results have shown alterations in all the studied tissues after 14 d of exposure (except for the intestinal epithelium), yet more severe effects were registered after 56 d of exposure. Herein we report histopathological alterations as a good biomarker for the evaluation of soil quality. We also demonstrate that morphological changes in the body wall and gastrointestinal tract, are important endpoints that could be added to earthworm's standardized tests, for the evaluation of soil toxicity, as part of the risk assessment of contaminated areas. PMID:21911243

  1. Characterization of two endoglucanases for the classification of the earthworm, Eisenia fetida Waki.

    PubMed

    Akazawa, Shin-ichi; Ikarashi, Yuki; Yarimizu, Jun; Yokoyama, Keisuke; Kobayashi, Tomoya; Nakazawa, Hikaru; Ogasawara, Wataru; Morikawa, Yasushi

    2015-01-01

    Eisenia fetida and Eisenia andrei are vermicomposting species that are used as model animals for testing chemical material toxicology. Eisenia spp. are grown commercially in various fields in Japan. However, these two species have not been classified because it is difficult to distinguish them morphologically; thus, all bred earthworms are called E. fetida. However, it has been proposed that these two species have different expression regulation mechanisms. Here, we classified a sample of earthworms purchased from several farms, confirming that both E. fetida and E. andrei are present in Japanese earthworm breeding programs. We also characterized two highly active endoglucanases (EfEG1 and EfEG2) from the E. fetida Waki strain, which contained strong fibrinolytic enzymes for improving human health. We confirmed that EfEG1 is 1371 bp long and belongs to GHF9. Thus, E. fetida Waki may have commercial application for biomass utilization and as a dietary health supplement. PMID:26295166

  2. Methods using earthworms for the evaluation of potentially toxic materials in soils

    SciTech Connect

    Neuhauser, E.F.; Loehr, R.C.; Malecki, M.R.

    1982-01-01

    The purpose of this study was to investigate the feasibility of using earthworms to indicate effects of potentially toxic wastes when such wastes are intentionally or accidentally added to soils. Initial work with metals has shown that earthworms exhibit specific growth and reproductive responses. These responses are related to the concentration and solubility of the metal. Of the metals tested, cadmium was found to be the most toxic, followed by nickel, copper, zinc, and lead. The metal concentration in earthworm tissue and the background manure-metal mixture was measured, permitting the concentration factor to be computed. The concentration factor is the ratio of the metal in the worm tissue to that in the surrounding manure-metal mixture. These and other studies in our laboratory have demonstrated that the methods described in this paper may be used to predict the effect of land-applied or atmospherically deposited residues on the soil biota.

  3. Testing the nutritional-limitation, predator-avoidance, and storm-avoidance hypotheses for restricted sea otter habitat use in the Aleutian Islands, Alaska.

    PubMed

    Stewart, Nathan L; Konar, Brenda; Tinker, M Tim

    2015-03-01

    Sea otters (Enhydra lutris) inhabiting the Aleutian Islands have stabilized at low abundance levels following a decline and currently exhibit restricted habitat-utilization patterns. Possible explanations for restricted habitat use by sea otters can be classified into two fundamentally different processes, bottom-up and top-down forcing. Bottom-up hypotheses argue that changes in the availability or nutritional quality of prey resources have led to the selective use of habitats that support the highest quality prey. In contrast, top-down hypotheses argue that increases in predation pressure from killer whales have led to the selective use of habitats that provide the most effective refuge from killer whale predation. A third hypothesis suggests that current restricted habitat use is based on a need for protection from storms. We tested all three hypotheses for restricted habitat use by comparing currently used and historically used sea otter foraging locations for: (1) prey availability and quality, (2) structural habitat complexity, and (3) exposure to prevailing storms. Our findings suggest that current use is based on physical habitat complexity and not on prey availability, prey quality, or protection from storms, providing further evidence for killer whale predation as a cause for restricted sea otter habitat use in the Aleutian Islands. PMID:25416538

  4. Avoiding Ticks

    MedlinePlus

    ... Avoiding ticks On people On pets In the yard Removing a tick Symptoms of tickborne illness Geographic ... ticks on your pets Preventing ticks in the yard File Formats Help: How do I view different ...

  5. Tracking earthworm communities from soil DNA.

    PubMed

    Bienert, Friederike; De Danieli, Sébastien; Miquel, Christian; Coissac, Eric; Poillot, Carole; Brun, Jean-Jacques; Taberlet, Pierre

    2012-04-01

    Earthworms are known for their important role within the functioning of an ecosystem, and their diversity can be used as an indicator of ecosystem health. To date, earthworm diversity has been investigated through conventional extraction methods such as handsorting, soil washing or the application of a mustard solution. Such techniques are time consuming and often difficult to apply. We showed that combining DNA metabarcoding and next-generation sequencing facilitates the identification of earthworm species from soil samples. The first step of our experiments was to create a reference database of mitochondrial DNA (mtDNA) 16S gene for 14 earthworm species found in the French Alps. Using this database, we designed two new primer pairs targeting very short and informative DNA sequences (about 30 and 70 bp) that allow unambiguous species identification. Finally, we analysed extracellular DNA taken from soil samples in two localities (two plots per locality and eight samples per plot). The two short metabarcode regions led to the identification of a total of eight earthworm species. The earthworm communities identified by the DNA-based approach appeared to be well differentiated between the two localities and are consistent with results derived from inventories collected using the handsorting method. The possibility of assessing earthworm communities from hundreds or even thousands of localities through the use of extracellular soil DNA will undoubtedly stimulate further ecological research on these organisms. Using the same DNA extracts, our study also illustrates the potential of environmental DNA as a tool to assess the diversity of other soil-dwelling animal taxa. PMID:22250728

  6. Earthworms, Dirt, and Rotten Leaves: An Exploration in Ecology.

    ERIC Educational Resources Information Center

    McLaughlin, Molly

    1994-01-01

    This article provides a model for inviting children to "an exploration in ecology" by observing earthworms. It gives reasons to explore earthworms and guides the investigator through a detailed examination of the worms to answer 21 observation questions. Explores the ways in which earthworms interact with their environment. (LZ)

  7. Design and experimental gait analysis of a multi-segment in-pipe robot inspired by earthworm's peristaltic locomotion

    NASA Astrophysics Data System (ADS)

    Fang, Hongbin; Wang, Chenghao; Li, Suyi; Xu, Jian; Wang, K. W.

    2014-03-01

    This paper reports the experimental progress towards developing a multi-segment in-pipe robot inspired by earthworm's body structure and locomotion mechanism. To mimic the alternating contraction and elongation of a single earthworm's segment, a robust, servomotor based actuation mechanism is developed. In each robot segment, servomotor-driven cords and spring steel belts are utilized to imitate the earthworm's longitudinal and circular muscles, respectively. It is shown that the designed segment can contract and relax just like an earthworm's body segment. The axial and radial deformation of a single segment is measured experimentally, which agrees with the theoretical predictions. Then a multisegment earthworm-like robot is fabricated by assembling eight identical segments in series. The locomotion performance of this robot prototype is then extensively tested in order to investigate the correlation between gait design and dynamic locomotion characteristics. Based on the principle of retrograde peristalsis wave, a gait generator is developed for the multi-segment earthworm-like robot, following which gaits of the robot can be constructed. Employing the generated gaits, the 8-segment earthworm-like robot can successfully perform both horizontal locomotion and vertical climb in pipes. By changing gait parameters, i.e., with different gaits, locomotion characteristics including average speed and anchor slippage can be significantly tailored. The proposed actuation method and prototype of the multi-segment in-pipe robot as well as the gait generator provide a bionic realization of earthworm's locomotion with promising potentials in various applications such as pipeline inspection and cleaning.

  8. Species-Specific Effects of Epigeic Earthworms on Microbial Community Structure during First Stages of Decomposition of Organic Matter

    PubMed Central

    Gómez-Brandón, María; Lores, Marta; Domínguez, Jorge

    2012-01-01

    Background Epigeic earthworms are key organisms in organic matter decomposition because of the interactions they establish with microorganisms. The earthworm species and the quality and/or substrate availability are expected to be major factors influencing the outcome of these interactions. Here we tested whether and to what extent the epigeic earthworms Eisenia andrei, Eisenia fetida and Perionyx excavatus, widely used in vermicomposting, are capable of altering the microbiological properties of fresh organic matter in the short-term. We also questioned if the earthworm-induced modifications to the microbial communities are dependent on the type of substrate ingested. Methodology/Principal Findings To address these questions we determined the microbial community structure (phospholipid fatty acid profiles) and microbial activity (basal respiration and microbial growth rates) of three types of animal manure (cow, horse and rabbit) that differed in microbial composition, after being processed by each species of earthworm for one month. No differences were found between earthworm-worked samples with regards to microbial community structure, irrespective of type of manure, which suggests the existence of a bottleneck effect of worm digestion on microbial populations of the original material consumed. Moreover, in mesocosms containing cow manure the presence of E. andrei resulted not only in a decrease in bacterial and fungal biomass, but also in a reduced bacterial growth rate and total microbial activity, while no such reduction was found with E. fetida and P. excavatus. Conclusions/Significance Our results point to the species of earthworm with its associated gut microbiota as a strong determinant of the process shaping the structure of microbial communities in the short-term. This must nonetheless be weighed against the fact that further knowledge is necessary to evaluate whether the changes in the composition of microbiota in response to the earthworm species is

  9. Enrofloxacin at environmentally relevant concentrations enhances uptake and toxicity of cadmium in the earthworm Eisenia fetida in farm soils.

    PubMed

    Li, Yinsheng; Tang, Hao; Hu, Yingxiu; Wang, Xiuhong; Ai, Xiaojie; Tang, Li; Matthew, Cory; Cavanagh, Jo; Qiu, Jiangping

    2016-05-01

    Individual and combined effects of enrofloxacin (EF) and cadmium (Cd) on the earthworm Eisenia fetida at environmentally relevant concentrations were investigated. EF is a veterinary antibiotic; Cd is an impurity in phosphatic fertiliser. For both, residues may accumulate in farm soils. In laboratory tests, over 98% of spiked EF was adsorbed by farm soils, with a half-life >8 weeks. However, earthworms absorbed less than 20% of spiked EF. Earthworms in soil with EF concentration 10 mg kg(-1) soil experienced transient oxidative stress and exhibited reduced burrowing activity and respiration after an 8-week exposure; EF at 0.1 and 1.0 mg kg(-1) soil did not elicit toxicity symptoms. When both were added, Cd did not affect EF uptake, but each increment of spiked EF increased Cd bioaccumulation and associated oxidative stress of earthworms, and also caused decreased burrow length and CO2 production. However, metallothionein induction was not affected. The enhanced toxicity of Cd to earthworms in the presence of EF at low environmental concentrations may have implications for the health and reproductive success of earthworm populations and highlights the importance of understanding effects of antibiotic contamination of farm soils, and of awareness of environmental effects from interaction between multiple contaminants. PMID:26852206

  10. An earthworm-like microrobot for colonoscopy.

    PubMed

    Wang, K D; Yan, G Z

    2006-01-01

    Miniature robotics for colonoscopy has become a hot research topic with the development of minimally invasive surgery (MIS). In this paper, a novel microrobot for colonoscopy that operates based on a simulation of the squirming motion of the earthworm is described. The robot uses a unique driving unit called a linear electromagnetic driver. The prototype measures 9.5 mm in diameter and 120 mm in length. It is driven by a linear direct current (DC) motor designed and manufactured by the authors. This paper describes the prototype, locomotion principle, and control system in detail. It then describes two models that were built to study the robot's ability to move in the viscoelastic colon environment. A slepe model of motion was developed and some mathematical evaluations of locomotion conditions were conducted. Experiments to test the creeping ability of the prototype on a slope were performed to verify these expressions. From the viscoelastic model relative to acting force between the robot and the colon, a transcendent equation about locomotive efficiency of the critical squirm step was deduced and solved to instruct the design of the robot. Last, in vitro experiments in the fresh colon of a pig were performed. The results show that this kind of microrobot can propel itself freely and reliably in the soft viscoelastic colon. Finally, future areas of research are noted. PMID:17190090

  11. Revising lysenin expression of earthworm coelomocytes.

    PubMed

    Opper, Balázs; Bognár, András; Heidt, Diána; Németh, Péter; Engelmann, Péter

    2013-03-01

    Lysenin is a species-specific bioactive molecule of Eisenia andrei earthworms. This protein is a potent antimicrobial factor; however its cellular expression and induction against pathogens are still not fully understood. We developed a novel monoclonal antibody against lysenin and applied this molecular tool to characterize its production and antimicrobial function. We demonstrated by flow cytometry and immunocytochemistry that one subgroup of earthworm immune cells (so called coelomocytes), the chloragocytes expressed the highest amount of lysenin. Then, we compared lysenin expression with earlier established coelomocyte (EFCC) markers. In addition, we determined by immunohistology of earthworm tissues that lysenin production is only restricted to free-floating chloragocytes. Moreover, we observed that upon in vitro Staphylococcus aureus but not Escherichia coli challenged coelomocytes over-expressed and then secreted lysenin. These results indicate that among subpopulations of coelomocytes, lysenin is mainly produced by chloragocytes and its expression can be modulated by Gram-positive bacterial exposure. PMID:23201038

  12. Glycosaminoglycans from earthworms (Eisenia andrei)

    PubMed Central

    Im, A-Rang; Park, Youmie; Sim, Joon-Soo; Zhang, Zhenqing; Liu, Zhenling

    2012-01-01

    The whole tissue of the earthworm (Eisenia andrei) was lyophilized and extracted to purify glycosaminoglycans. Fractions, eluting from an anion-exchange column at 1.0 M and 2.0 M NaCl, showed the presence of acidic polysaccharides on agarose gel electrophoresis. Monosaccharide compositional analysis showed that galactose and glucose were most abundant monosaccharides in both fractions. Depolymerization of the polysaccharide mixture with glycosaminoglycandegrading enzymes confirmed the presence of chondroitin sulfate/dermatan sulfate and heparan sulfate in the 2.0 M NaCl fraction. The content of GAGs (uronic acid containing polysaccharide) in the 2.0 M NaCl fraction determined by carbazole assay was 2%. Disaccharide compositional analysis using liquid chromatography-electrospray ionization mass spectrometry (LC-ESI-MS) analysis after chondroitinase digestion (ABC and ACII), showed that the chondroitin sulfate/dermatan sulfate contained a 4-O-sulfo (76%), 2,4-di-O-sulfo (15%), 6-O-sulfo (6%), and unsulfated (4%) uronic acid linked N-acetylgalactosamine residues. LC-ESI-MS analysis of heparin lyase I/II/III digests demonstrated the presence of N-sulfo (69%), N-sulfo-6-O-sulfo (25%) and 2-O-sulfo-N-sulfo-6-O-sulfo (5%) uronic acid linked N-acetylglucosamine residues. PMID:20013352

  13. Biochemical diversity of betaines in earthworms

    SciTech Connect

    Liebeke, Manuel; Bundy, Jacob G.

    2013-01-25

    Highlights: ► We develop a method for rapid untargetted analysis of betaines. ► We profile betaines in a comparative study of ten earthworm species. ► Earthworms contain a surprisingly high number of different betaine metabolites. ► Earthworms contain betaines normally seen only in plants or marine animals. -- Abstract: The ability to accumulate osmoprotectant compounds, such as betaines, is an important evolutionary feature in many organisms. This is particularly the case for organisms that live in variable environments, which may have fluctuations in moisture and salinity levels. There is, surprisingly, very little known about betaines in soil invertebrates in general, and there is almost no information about earthworms – a group that are important ‘ecosystem engineers’ and key indicators of soil health. Here, we describe a fast and reliable {sup 1}H–{sup 13}C heteronuclear single quantum coherence (HSQC) 2D NMR approach for the metabolic profiling of a series of betaines and related metabolites in tissue extracts, and list {sup 1}H and {sup 13}C chemical shifts for the trimethylammonium signal for 23 such compounds. The analysis of ten different species from three different families (Lumbricidae, Megascolecidae and Glossoscolecidae) showed an unexpected diversity of betaines present in earthworms. In total ten betaines were identified, including hydroxyproline-betaine, proline-betaine, taurine-betaine, GABA-betaine and histidine-betaine, and a further eleven as-yet unassigned putative betaine metabolites detected. The findings clearly indicate a hitherto-unappreciated important role for betaine metabolism in earthworms.

  14. A better method for assessing sublethal effects of soils to the earthworm Eisenia foetida

    SciTech Connect

    Gibbs, M.H.; Wicker, L.F.; Stewart, A.J.

    1994-12-31

    The authors have developed and tested a procedure which allows quantification of growth and reproductive effects of contaminated soils to the earthworm, Eisenia foetida. The procedure monitors isolated pairs of earthworms and generates a higher ratio of data per organism than other commonly used procedures which require larger numbers of earthworms per experimental unit. The procedure also incorporates an accurate technique for measuring adult growth. The method has high sensitivity and is cost-effective. The method was applied to a variety of soil-testing problems to demonstrate its versatility and provide validation. A food-and-substrate trial demonstrated the sensitivity of the method and the need for food supplementation in OECD artificial soil to stimulate earthworm reproduction. A trial to examine a soil bioremediation technology revealed the advantage of measuring both growth and reproduction and highlighted the usefulness of a single integrated measure of these two responses. The method then was applied as a fast-screening method for field soils in a large-scale ecological risk assessment. Finally, a reference toxicant, applied in dilution series, demonstrated that responses of Eisenia foetida to their method are similar to their responses to the OECD artificial soil test. Collectively, results of this study indicate that their procedure can be used both for regulatory and compliance needs within the framework of ecological risk assessment.

  15. Bioaccumulation and Elimination of the Herbicide Clomazone in the Earthworms Eisenia fetida.

    PubMed

    Cao, Jia; Li, Ping; Li, Qing X; Zheng, Pengfei; Diao, Xiaoping

    2015-11-01

    Acute toxicity, bioaccumulation, and elimination of herbicide clomazone in the earthworm Eisenia fetida were investigated in the different exposure systems. The LC50 values of clomazone on earthworms were 5.6 μg cm(-2) in the contact filter paper test (48 h), 174.9 mg kg(-1) (7 days) and 123.4 mg kg(-1) (14 days) in artificial soil test, respectively. Clomazone could rapidly bioaccumulate in earthworms and reached the highest concentration after 3 days exposure, with the maximum concentrations of 9.0, 35.3 and 142.3 mg kg(-1) at 10.0, 40.0 and 160.0 mg kg(-1) of clomazone, respectively. Clomazone uptake showed a good correlation with exposure concentration. After the 14th day, clomazone declined to minimum value. About 74%-80% of accumulated clomazone was eliminated within 1 day after exposed to clomazone-free soil. However, a trace amount of clomazone persisted for a relatively long time in earthworms. PMID:26370279

  16. Combined effects of copper, desiccation, and frost on the viability of earthworm cocoons

    SciTech Connect

    Holmstrup, M.; Petersen, B.F. |; Larsen, M.M.

    1998-01-01

    The effects of heavy metal pollution on earthworms have been extensively studied, but no studies have examined how earthworms react if they are simultaneously exposed to metal pollution and climatic stress. This question has been addressed in a laboratory study where cocoons of Aporrectodea caliginosa and Dendrobaena octaedra were initially exposed to copper in aqueous solutions of copper chloride and thereafter exposed to realistic degrees of either desiccation or frost. Earthworm embryos absorbed copper in amounts comparable to concentrations found in various tissues of earthworms from metal-polluted soils. Desiccation and copper exposure in combination had synergistic effects on survival rates for both species. For example, at full saturation, the NOEC (the highest tested concentration with no statistically significant effect) for copper of A. caliginosa was 12 mg/L, whereas at 97% relative humidity it was only 6 mg/L. Frost and copper exposure in combination also showed synergistic effects in some experiments. No cocoons of A. caliginosa exposed to 20 mg copper/L were viable after exposure to {minus}3 C but at 0 C viability was as high as 95%. The same tendency was seen in D. octaedra but not as clearly as in A/. caliginosa. A change of the environmental conditions (moisture, temperature) to increasing severity caused a shift in the statistically derived NOEC toward lower critical values of copper. The involvement of combination effects in ecotoxicological tests could therefore improve risk assessment of soil-polluting compounds.

  17. Neurotoxicity and biochemical responses in the earthworm Pheretima hawayana exposed to TiO2NPs.

    PubMed

    Khalil, Abdelmonem M

    2015-12-01

    Serious concerns have been expressed about potential risks of manufactured TiO2NPs. In this research, toxicity of nanoparticulate and bulk TiO2 were examined to the earthworm Pheretima hawayana. The 24-h median lethal concentration (LC50) and sublethal endpoints were assessed. Both NPs and their bulk counterparts were toxic. The 24-h LC50 for TiO2NPs (145.36 mg kg(-1)) was highly toxic than that of bulk TiO2 (357.77 mg kg(-1)). The aim of the present work is to evaluate the suitability of P. hawayana and its biochemical responses to be used as a bioindicator organism and biomarkers of TiO2 toxicity. Earthworms were exposed to three sublethal concentrations of TiO2NPs (1, 10 and 100 µg kg(-1)) for 28 days to test acetylcholinesterase (AChE), antioxidant enzymes (superoxide dismutase: SOD and catalase: CAT) activities and MDA content. The response of the antioxidant enzymes combined with AChE inhibition and MDA accumulation indicated that TiO2NPs could induce significant impairments to the earthworms at the actual environment tested concentrations. The results pointed out the high sensitivity of the antioxidant and oxidative stress related responses to TiO2NPs exposure, demonstrating their usefulness in environmental monitoring and risk assessment. The study highlights also the usefulness of earthworm P. hawayana as potential bioindicator species for assessing the risk of nanoparticles environmental contamination. PMID:26398239

  18. Earthworm Preference Bioassays to Evaluate Land Management Practices.

    PubMed

    Bouldin, Jennifer L; Klasky, John W P; Green, V Steven

    2016-06-01

    Earthworm preference tests, especially in soil-dosed exposures, can be an informative tool for assessing land management practices. Agricultural management intended to increase crop yield and improve soil sustainability includes physical manipulation of topsoil through conventional tillage, reduced or no-tillage, and/or winter cover crops. Soil amendments include the addition of inorganic nitrogen or organic nitrogen derived from soil amendments including biosolids from sewage treatment plants, poultry litter, or locally available industrial effluent. This study used 48-h Eisenia fetida preference tests to assess impacts of agricultural management practices on soil macrofauna. Although in laboratory-dosed exposures, E. fetida preferred biosolid-dosed soils (80 %-95 % recovery) over control soils, the same results were not found with field soils receiving biosolid amendments (33 % recovery). Poultry litter-amended soils (68 % recovery) were preferred over control soils. No differences were measured between tilled fields and controls, and earthworms preferred control soils over those from fields with no-tillage and cover crops. Soil assessments through laboratory exposures such as these allows science-based agricultural management decisions to maintain or improve soil health. PMID:26873732

  19. Comparative toxicity in earthworms Eisenia fetida and Lumbricus terrestris exposed to cadmium nitrate using artificial soil and filter paper protocols

    SciTech Connect

    Fitzpatrick, L.C.; Goven, A.J.; Muratti-Ortiz, J.F.

    1996-07-01

    Earthworms are ideal soil organisms for use in terrestrial ecotoxicology. As such, several earthworm protocols have been developed for testing toxic potential of chemicals and contaminated soils. Of these, the 48-h filter paper contact (FP) and the 14-d artificial soil exposure (AS) protocols, using mortality (LC50) as the toxic endpoint and Eisenia fetida as the test species, have received the most attention, with the latter being adopted by both OECD and EEC in Europe and the Environmental Protection Agency (USEPA) in the United States. Although the FP technique, adopted by EEC, provides for inexpensive reproducible toxicity screening for chemicals (i.e. establishing relative toxicities), it has been criticized for lacking the ecotoxicological relevance of the AS protocol. Choice of earthworm species for laboratory testing also has been controversial. The manure worm, E. fetida, is criticized for not being sufficiently sensitive to chemicals or representative of {open_quotes}typical{close_quotes} earthworms. Lumbricus terrestris and Apporectodea caliginosa have been suggested as more sensitive and ecologically relevant earthworms by Dean-Ross and Martin, respectively. This paper compares the AS and FP protocols in assessing toxicity of cadminum to L. terrestris and E. fetida using LC50s and LC50s. 19 refs., 2 tabs.

  20. POPULATION DYNAMICS OF AMBIENT AND ALTERED EARTHWORM COMMUNITIES IN ROW-CROP AGROECOSYSTEMS IN OHIO, USA

    EPA Science Inventory

    Although earthworms are known to influence agroecosystem processes, there are relatively few long-term studies addressing population dynamics under cropping systems in which earthworm populations were intentionally altered. We assessed earthworm communities from fall 1994 to spr...

  1. Testing conditions in shock-based contextual fear conditioning influence both the behavioral responses and the activation of circuits potentially involved in contextual avoidance.

    PubMed

    Viellard, Juliette; Baldo, Marcus Vinicius C; Canteras, Newton Sabino

    2016-12-15

    Previous studies from our group have shown that risk assessment behaviors are the primary contextual fear responses to predatory and social threats, whereas freezing is the main contextual fear response to physically harmful events. To test contextual fear responses to a predator or aggressive conspecific threat, we developed a model that involves placing the animal in an apparatus where it can avoid the threat-associated environment. Conversely, in studies that use shock-based fear conditioning, the animals are usually confined inside the conditioning chamber during the contextual fear test. In the present study, we tested shock-based contextual fear responses using two different behavioral testing conditions: confining the animal in the conditioning chamber or placing the animal in an apparatus with free access to the conditioning compartment. Our results showed that during the contextual fear test, the animals confined to the shock chamber exhibited significantly more freezing. In contrast, the animals that could avoid the conditioning compartment displayed almost no freezing and exhibited risk assessment responses (i.e., crouch-sniff and stretch postures) and burying behavior. In addition, the animals that were able to avoid the shock chamber had increased Fos expression in the juxtadorsomedial lateral hypothalamic area, the dorsomedial part of the dorsal premammillary nucleus and the lateral and dorsomedial parts of the periaqueductal gray, which are elements of a septo/hippocampal-hypothalamic-brainstem circuit that is putatively involved in mediating contextual avoidance. Overall, the present findings show that testing conditions significantly influence both behavioral responses and the activation of circuits involved in contextual avoidance. PMID:27544875

  2. Determining the influence of rainfall patterns and carbendazim on the surface activity of the earthworm Lumbricus terrestris.

    PubMed

    Ellis, Sian R; Hodson, Mark E; Wege, Phil

    2010-08-01

    Carbendazim is highly toxic to earthworms and is used as a standard control substance when running field-based trials of pesticides, but results using carbendazim are highly variable. In the present study, impacts of timing of rainfall events following carbendazim application on earthworms were investigated. Lumbricus terrestris were maintained in soil columns to which carbendazim and then deionized water (a rainfall substitute) were applied. Carbendazim was applied at 4 kg/ha, the rate recommended in pesticide field trials. Three rainfall regimes were investigated: initial and delayed heavy rainfall 24 h and 6 d after carbendazim application, and frequent rainfall every 48 h. Earthworm mortality and movement of carbendazim through the soil was assessed 14 d after carbendazim application. No detectable movement of carbendazim occurred through the soil in any of the treatments or controls. Mortality in the initial heavy and frequent rainfall was significantly higher (approximately 55%) than in the delayed rainfall treatment (approximately 25%). This was due to reduced bioavailability of carbendazim in the latter treatment due to a prolonged period of sorption of carbendazim to soil particles before rainfall events. The impact of carbendazim application on earthworm surface activity was assessed using video cameras. Carbendazim applications significantly reduced surface activity due to avoidance behavior of the earthworms. Surface activity reductions were least in the delayed rainfall treatment due to the reduced bioavailability of the carbendazim. The nature of rainfall events' impacts on the response of earthworms to carbendazim applications, and details of rainfall events preceding and following applications during field trials should be made at a higher level of resolution than is currently practiced according to standard International Organization for Standardization protocols. PMID:20821637

  3. Visualization of enzyme activities inside earthworm pores

    NASA Astrophysics Data System (ADS)

    Hoang, Duyen; Razavi, Bahar S.

    2015-04-01

    In extremely dynamic microhabitats as bio-pores made by earthworm, the in situ enzyme activities are assumed as a footprint of complex biotic interactions. Our study focused on the effect of earthworm on the enzyme activities inside bio-pores and visualizing the differences between bio-pores and earthworm-free soil by zymography technique (Spohn and Kuzyakov, 2013). For the first time, we aimed at quantitative imaging of enzyme activities in bio-pores. Lumbricus terrestris L. was placed into transparent box (15×20×15cm). After two weeks when bio-pore systems were formed by earthworms, we visualized in situ enzyme activities of five hydrolytic enzymes (β-glucosidase, cellobiohydrolase, chitinase, xylanase, leucine-aminopeptidase, and phosphatase. Zymography showed higher activity of β-glucosidase, chitinase, xylanase and phosphatase in biopores comparing to bulk soil. However, the differences in activity of cellobiohydrolase and leucine aminopeptidase between bio-pore and bulk soil were less pronounced. This demonstrated an applicability of zymography approach to monitor and to distinguish the in situ activity of hydrolytic enzymes in soil biopores.

  4. Easy Extraction of Roundworms from Earthworm Hosts.

    ERIC Educational Resources Information Center

    Eyster, Linda S.; Fried, Bernard

    2000-01-01

    Describes the inexpensive and safe method of using roundworms in the classroom or laboratories. Because parasitic infections are so common, students should learn about worms. Provides statistics on just how many people have a worm infection in the world. Explains how to study living nematodes, and obtain and use earthworms. (Contains 13…

  5. Earthworms, pesticides and sustainable agriculture: a review.

    PubMed

    Datta, Shivika; Singh, Joginder; Singh, Sharanpreet; Singh, Jaswinder

    2016-05-01

    The aim of this review is to generate awareness and understand the importance of earthworms in sustainable agriculture and effect of pesticides on their action. The natural resources are finite and highly prone to degradation by the misuse of land and mismanagement of soil. The world is in utter need of a healthy ecosystem that provides with fertile soil, clean water, food and other natural resources. Anthropogenic activities have led to an increased contamination of land. The intensification of industrial and agricultural practices chiefly the utilization of pesticides has in almost every way made our natural resources concave. Earthworms help in a number of tasks that support many ecosystem services that favor agrosystem sustainability but are degraded by exhaustive practices such as the use of pesticides. The present review assesses the response of earthworm toward the pesticides and also evaluates the relationship between earthworm activity and plant growth. We strictly need to refresh and rethink on the policies and norms devised by us on sustainable ecology. In an equivalent way, the natural resources should be utilized and further, essential ways for betterment of present and future livelihood should be sought. PMID:26951221

  6. A field test for host discrimination and avoidance behavior for Rhagoletis pomonella flies in the western United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prezygotic isolation due to habitat choice is important to many models of speciation-with-gene-flow. Habitat choice is usually thought to occur through positive preferences of organisms for particular environments. However, avoidance of non-natal environments may also play a role in choice and have ...

  7. Transformation of 2,4,6-trinitrotoluene in soil in the presence of the earthworm Eisenia andrei

    SciTech Connect

    Renoux, A.Y.; Sarrazin, M.; Hawari, J.; Sunahara, G.I.

    2000-06-01

    The ability of the earthworm Eisenia andrei to metabolize 2,4,6-trinitrotoluene (TNT) was studied in experiments with TNT-spiked soils, dermal contact tests, and with an in vitro assay. Lethality of TNT in a forest sandy soil was first determined. Then TNT at lethal and sublethal concentrations was applied to the same soil and was monitored along with its metabolites in extracts of soil and earthworm tissue for up to 14 d post application. High performance liquid chromatography-ultra violet analyses indicated that TNT was transformed in the presence of E. andrei by a reductive pathway to 2-amino-3,6-dinitrotoluene (2-ADNT), 4-amino-2,6-dinitrotoluene (4-ADNT), 2,4-diamino-6-nitrotoluene (2.4-DANT), and traces of 2,6-diamino-4-nitrotoluene (2,6-DANT) in earthworm tissues. This transformation could be explained by either a metabolic mechanism within the earthworm or by the enhancement of an earthworm-associated microbial activity or both. The TNT concentrations decreased from the spiked soils. However, the monoamino-dinitrotoluene (2-ADNT and 4-ADNT) concentrations increased with exposure duration and were dependent on the initial TNT soil concentrations. This was also observed to a lesser extent in the TNT-spiked soils with no earthworms present. The biotransformation of TNT into 2-ADNT, 4-ADNT, and 2,4-DANT and the presence of these metabolites in E. andrei after dermal contact on TNT-spiked filter paper showed that dermal uptake can be a significant exposure route for TNT. In vitro experiments showed that earthworm homogenate could metabolize TNT and form 2-ADNT and 4-ADNT at room temperature and at 37 C. This effect was inhibited by heat inactivation prior to incubation or by incubation at 4 C, suggesting that the biotransformation of TNT in the presence of E. andrei may be enzymatic in nature.

  8. Trophic transfer of silver nanoparticles from earthworms disrupts the locomotion of springtails (Collembola).

    PubMed

    Kwak, Jin Il; An, Youn-Joo

    2016-09-01

    Understanding how nanomaterials are transferred through food chains and evaluating their resulting toxicity is important. However, limited research has been conducted on the toxic consequences of trophically transferred nanomaterials in terrestrial ecosystems. In this study, we documented the adverse effects of trophically transferred silver nanoparticles (AgNPs) in a soil-earthworm (Eisenia andrei)-Collembola (Lobella sokamensis) food chain. We exposed E. andrei to soil with AgNPs at concentrations of 50, 200, and 500μg AgNPs/g soil dry weight and assessed their survival after 7days. Trophic-transfer containers were then prepared and E. andrei that survived the 7days test period were washed, killed in boiling water, and added to the containers with L. sokamensis. We noted negligible effects and low bioaccumulation at the lowest AgNP concentration (50μg AgNPs/g soil dry weight) in earthworms and the L. sokamensis that fed on them. The highest concentration of AgNPs (500μg AgNPs/g soil dry weight) resulted in juvenile earthworm mortality and increased transfer of AgNPs to Collembola, which subsequently inhibited their locomotion. To our knowledge, this is the first study to document the trophic transfer and adverse effects of AgNPs in a soil-earthworm-Collembola food chain, a common prey-decomposer interaction in soil ecosystems. PMID:27187058

  9. Evaluation of epoxiconazole bioavailability in soil to the earthworm Aporrectodea icterica.

    PubMed

    Nélieu, S; Delarue, G; Ollivier, E; Awad, P; Fraillon, F; Pelosi, C

    2016-02-01

    In soil, the determination of total concentration using an exhaustive extraction method has little relevance to evaluate the exposure of an organism to a chemical, because of sorption processes. This study aims to propose a mild extraction method to evaluate the bioavailability of the fungicide epoxiconazole to the earthworm Aporrectodea icterica. Experiments were conducted in soils presenting various textures and organic carbon contents, spiked with formulated epoxiconazole 7 to 56 days prior to their extraction. In parallel, the epoxiconazole concentration was determined in exposed earthworms and the fungicide's effects were evaluated by measuring weight gain, enzymatic activities and total protein contents. Among the various mild chemical solvents tested to evaluate the environmental availability of the fungicide, the 50 mM hydroxypropyl-β-cyclodextrin solution allowed to extract around 30% of epoxiconazole. This percentage corresponded to the ratio determined in exposed A. icterica under similar soil conditions. Furthermore, this mild method was demonstrated to be sensitive to soil sorption capacities and to ageing. The mild extraction method was then applied to explore the relationship between total and (bio)available concentrations in soil and in A. icterica, over 7- or 28-day exposure time. This demonstrated the proportionality between epoxiconazole concentration in earthworm and available in soil (up to 96%, with regression coefficient R(2) = 0.98). Sublethal effects on earthworm remained not significant. PMID:26315591

  10. The Performance of Earthworm Based Earthquake Alarm Reporting System in Taiwan

    NASA Astrophysics Data System (ADS)

    Chen, Ta-Yi; Hsiao, Nai-Chi; Wu, Yih-Min

    2016-04-01

    The Central Weather Bureau of Taiwan has operated an earthquake early warning (EEW) system and issued warnings to schools and government agencies since 2014. Because the real-time seismic data streams are integrated by the Earthworm software, some EEW modules were created under the Earthworm platform. The system is named Earthworm Based Earthquake Alarm Reporting (eBEAR) system, which is currently operating. The eBEAR system consists of new Earthworm modules for managing P-wave phase picking, trigger associations, hypocenter locations, magnitude estimations, and alert filtering prior to broadcasting. Here, we outline the methodology and performance of the eBEAR system. The online performance of the eBEAR system indicated that the average reporting times afforded by the system are approximately 15 and 26 s for inland and offshore earthquakes, respectively. Comparing to the earthquake catalog, the difference of the epicenters are less than 10 km for inland earthquakes; the difference of the magnitude are about 0.3. No false alarms generated by the system, but there were three false alarms issued by human. Due to the wrong operations, the EEW information created by off-line test were sent. However, we have learned from it and improved the standard operation procedure in the EEW system.

  11. Earthworms and legumes control litter decomposition in a plant diversity gradient.

    PubMed

    Milcu, Alexandru; Partsch, Stephan; Scherber, Christoph; Weisser, Wolfgang W; Scheu, Stefan

    2008-07-01

    The role of species and functional group diversity of primary producers for decomposers and decomposition processes is little understood. We made use of the "Jena Biodiversity Experiment" and tested the hypothesis that increasing plant species (1, 4, and 16 species) and functional group diversity (1, 2, 3, and 4 groups) beneficially affects decomposer density and activity and therefore the decomposition of plant litter material. Furthermore, by manipulating the densities of decomposers (earthworms and springtails) within the plant diversity gradient we investigated how the interactions between plant diversity and decomposer densities affect the decomposition of litter belonging to different plant functional groups (grasses, herbs, and legumes). Positive effects of increasing plant species or functional group diversity on earthworms (biomass and density) and microbial biomass were mainly due to the increased incidence of legumes with increasing diversity. Neither plant species diversity nor functional group diversity affected litter decomposition, However, litter decomposition varied with decomposer and plant functional group identity (of both living plants and plant litter). While springtail removal generally had little effect on decomposition, increased earthworm density accelerated the decomposition of nitrogen-rich legume litter, and this was more pronounced at higher plant diversity. The results suggest that earthworms (Lumbricus terrestris L.) and legumes function as keystone organisms for grassland decomposition processes and presumably contribute to the recorded increase in primary productivity with increasing plant diversity. PMID:18705374

  12. The influence of earthworms on the mobility of microelements in soil and their availability for plants

    NASA Astrophysics Data System (ADS)

    Bityutskii, N. P.; Kaidun, P. I.

    2008-12-01

    The influence of earthworms ( Aporrectodea caliginosa, Lumbricus rubellus, L. terrestris, and Eisenia fetida) on the mobility of microelements and their availability for plants was studied. The contents of water-soluble Fe and Mn compounds extracted from the coprolites were 5-10 times higher than that in the soil (enriched in calcium carbonate and dried) consumed by the earthworms. This digestion-induced effect became higher with the age of the coprolites (up to 9 days) and took place under their alkalization. In the excreta (surface + enteric) of earthworms, the Fe concentration exceeded those of Mn and Zn by many times. Iron and manganese were mostly concentrated (>80% and >60%, respectively) in the organic part of the excrements. In the tests with hydroponics, the excreta were found to be a source of iron compounds available for plants that were similar to Fe2(SO4)3 or Fe-citrate by their physiological effect in the case when the Fe concentration in the excretions was above 0.7 μM. However, the single application of excreta of different earthworm species into the CaCO3 enriched soil did not significantly affect the plant (cucumber) nutrition. The analysis of the transport of microelements with xylem sap showed that this fact appeared to be due to the absence of an Fe deficit in the cucumber plants because of their high capability for the absorption of weakly soluble iron compounds.

  13. Bioaccumulation of organic chemicals in contaminated soils: evaluation of bioassays with earthworms.

    PubMed

    Jager, Tjalling; van der Wal, Leon; Fleuren, Roel H L J; Barendregt, Arjan; Hermens, Joop L M

    2005-01-01

    Earthworms live in close contact with the soil and can thus be considered representative for the bioavailability of chemicals at contaminated sites. Bioavailability can either be assessed by analyzing earthworms from contaminated locations or by exposing laboratory-reared specimens to soil samples from the field (bioassays). In this study, we investigate the relevance of bioassays by using an extended experimental design (to identify signs of depletion of the bioavailable phase by the earthworms) and by using two species of earthworm (the standard test species Eisenia andrei and the field-relevant Aporrectodea caliginosa). Furthermore, bioassay results are compared to body residues of worms collected from the field site: a heavily polluted polder, amended with dredge spoil. We focused on telodrin, dieldrin, hexachlorobenzene, and eight PCBs. With our bioassay design, it was shown that depletion was unlikely, although more subtle effects could have occurred (e.g., changes in sorption during the experiments). E. andrei is a good choice for bioassays because its body residues correlate well to those in A. caliginosa, as well as to those in the field-collected worms. Nevertheless, E. andrei accumulated slightly more than the other species and appeared to be more sensitive to the conditions in soil from one of our sites. PMID:15667108

  14. LBP/BPI homologue in Eisenia andrei earthworms.

    PubMed

    Škanta, František; Procházková, Petra; Roubalová, Radka; Dvořák, Jiří; Bilej, Martin

    2016-01-01

    LBP/BPIs are pattern recognition receptors that are often present in vertebrates and in invertebrates, and they play a defense role against pathogens. We have identified 1698 bp cDNA sequence from the Eisenia andrei earthworm with predicted amino acid sequence that shares homology with the LBP/BPI family (EaLBP/BPI). Sequence analysis of EaLBP/BPI proved the existence of two conserved domains with the potential ability to bind LPS. The predicted molecular mass of the EaLBP/BPI protein is 53.5 kDa, and its high basicity (pI 9.8) is caused by its high arginine content. Constitutive transcription of the Ealbp/bpi gene was shown in all tested tissues, with the highest level in coelomocytes and seminal vesicles; the lowest level was detected in the intestine. On the contrary, another earthworm LPS-binding molecule CCF (coelomic cytolytic factor) was expressed only in the intestine and coelomocytes. In E. andrei coelomocytes, the transcription of Ealbp/bpi gene was up-regulated in response to bacterial stimulation, reaching a maximum at 8 and 16 h post stimulation with Bacillus subtilis and Escherichia coli, respectively. PMID:26297397

  15. Interactions between earthworm hemolysins and sheep red blood cell membranes.

    PubMed

    Roch, P; Canicatti, C; Valembois, P

    1989-08-01

    The hemolytic activity exhibited by the coelomic fluid of the Annelid Eisenia fetida andrei is mediated by two lipoproteins of mass 40 and 45 kDa, each of them capable of hemolysis. Such an activity is not inhibited by zymosan, inulin or lipopolysaccharide (LPS), nor by hydrazine or methylamine, suggesting that earthworm hemolysins are not related to C3 or C3b complement components. Among the membrane lipids tested (phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, sphingomyelin and cholesterol) only sphingomyelin inhibited hemolysis. The analysis of E.f. andrei proteins bound to sphingomyelin microvesicles, as well as to sheep red blood cell (SRBC) membranes, revealed a polymerization of E.f. andrei 40 kDa and/or 45 kDa hemolysins. Consequently, sphingomyelin appears a likely candidate for hemolytic complex receptor. Electron microscopy observations suggested that the polymerization causes an open channel through the lipid bilayer. As demonstrated using metal ions, heparin, chondroitin sulfate, poly(L-lysine) and protamine chloride, the mode of action of earthworm hemolytic complex is not analogous to that of C9 or perforine. PMID:2758056

  16. The bioavailability of chemicals in soil for earthworms

    USGS Publications Warehouse

    Lanno, R.; Wells, J.; Conder, Jason M.; Bradham, K.; Basta, N.

    2004-01-01

    The bioavailability of chemicals to earthworms can be modified dramatically by soil physical/chemical characteristics, yet expressing exposure as total chemical concentrations does not address this problem. In order to understand the effects of modifying factors on bioavailability, one must measure and express chemical bioavailability to earthworms in a consistent, logical manner. This can be accomplished by direct biological measures of bioavailability (e.g., bioaccumulation, critical body residues), indirect biological measures of bioavailability (e.g., biomarkers, reproduction), or indirect chemical measures of bioavailability (e.g., chemical or solid-phase extracts of soil). If indirect chemical measures of bioavailability are to be used, they must be correlated with some biological response. Bioavailability can be incorporated into ecological risk assessment during risk analysis, primarily in the estimation of exposure. However, in order to be used in the site-specific ecological risk assessment of chemicals, effects concentrations must be developed from laboratory toxicity tests based on exposure estimates utilizing techniques that measure the bioavailable fraction of chemicals in soil, not total chemical concentrations. ?? 2003 Elsevier Inc. All rights reserved.

  17. Long-term efficiency of soil stabilization with apatite and Slovakite: the impact of two earthworm species (Lumbricus terrestris and Dendrobaena veneta) on lead bioaccessibility and soil functioning.

    PubMed

    Tica, D; Udovic, M; Lestan, D

    2013-03-01

    Remediation soil is exposed to various environmental factors over time that can affect the final success of the operation. In the present study, we assessed Pb bioaccessibility and microbial activity in industrially polluted soil (Arnoldstein, Austria) stabilized with 5% (w/w) of Slovakite and 5% (w/w) of apatite soil after exposure to two earthworm species, Lumbricus terrestris and Dendrobaena veneta, used as model environmental biotic soil factors. Stabilization resulted in reduced Pb bioaccessibility, as assessed with one-step extraction tests and six-step sequential extraction, and improved soil functioning, mirrored in reduced β-glucosidase activity in soil. Both earthworm species increased Pb bioaccessibility, thus decreasing the initial stabilization efficacy and indicating the importance of considering the long-term fate of remediated soil. The earthworm species had different effects on soil enzyme activity, which can be attributed to species-specific microbial populations in earthworm gut acting on the ingested soil. PMID:23219407

  18. Relation of pH and other soil variables to concentrations of Pb, Cu, Zn, Cd, and Se in earthworms

    USGS Publications Warehouse

    Beyer, W.N.; Hensler, G.L.; Moore, J.

    1987-01-01

    Various soil treatments (clay, composted peat, superphosphate, sulfur, calcium carbonate, calcium chloride, zinc chloride, selenous acid) were added to experimental field plots to test the effect of different soil variables on the concentrations of 5 elements in earthworms (Pb, Cu, Zn, Cd, Se). Concentrations of the 5 elements were related to 9 soil variables (soil Pb, soil Cu, soil Zn, pH, organic matter, P, K, Mg, and Ca) with linear multiple regression. Lead concentrations in earthworms were positively correlated with soil Pb and soil organic matter, and negatively correlated with soil pH and soil Mg, with an R2 of 64%. Se concentrations were higher in earthworms from plots amended with Se, and Zn concentrations were higher in earthworms from plots amended with Zn. However, none of the other soil variables had important effects on the concentrations of Cu, Zn, Cd and Se in earthworms. Although some significant statistical relations were demonstrated, the values of r2 of all relations (> 20%) were so low that they had little predictive value.

  19. Interaction of citrate-coated silver nanoparticles with earthworm coelomic fluid and related cytotoxicity in Eisenia andrei.

    PubMed

    Kwak, Jin Il; Lee, Woo-Mi; Kim, Shin Woong; An, Youn-Joo

    2014-11-01

    Understanding the interaction of nanoparticles with biological fluid is important for predicting the behavior and toxicity of nanoparticles in living systems. The earthworm Eisenia andrei was exposed to citrate-coated silver nanoparticles (cAgNPs), and the interaction of cAgNPs with earthworm coelomic fluid (ECF), the cytotoxicity of cAgNPs in earthworm coelomocytes was assessed. The neutral red retention assay showed a reduction in lysosomal stability after exposure. The toxicity of silver ions dissolved from cAgNPs in the soil medium was not significant. The aggregation and dissolution of cAgNPs increased in ECF, which contains various electrolytes that alter the properties of nanoparticles, and their subsequent toxicity. Microscopic and dissolution studies demonstrated that the aggregation of cAgNPs rapidly increased, and readily dissolved in ECF. The bioavailability of cAgNPs to earthworms induced lysosomal cytotoxicity. This is the first report to test the interaction and lysosomal cytotoxicity of nanoparticles in earthworm biofluids. PMID:24532537

  20. Effect of earthworms (Eisenia fetida) on the fractionation and bioavailability of rare earth elements in nine Chinese soils.

    PubMed

    Wen, Bei; Liu, Ying; Hu, Xiao-yu; Shan, Xiao-quan

    2006-05-01

    The effect of earthworm (Eisenia fetida) activity on soil pH, dissolved organic carbon (DOC), fraction distribution pattern and bioavailability of rare earth elements (REEs) Y, La, Ce, Pr and Nd in nine Chinese soils were investigated using pot experiments. A three-step extraction procedure recommended by the European Community (Standards, Measurements and Testing Programme) was used to fractionate REEs in soils into water soluble, exchangeable and carbonate bound (B1), Fe- and Mn-oxides bound (B2) and organic matter and sulfide bound (B3). Inoculated with earthworms, the soil pH, DOC and water-soluble rare earth elements fraction increased. A significant correlation was obtained between the increased DOC and the increased water-soluble REEs. REEs in fraction B1 increased after earthworm inoculation, while those in fraction B3 decreased. No significant differences were observed for REEs in fraction B2. The biomass and the concentrations of REEs in wheat shoots and roots increased after the treatment with earthworms. The results demonstrated that earthworm activity increased the mobility and bioavailability of REEs in soils. PMID:16289225

  1. Root foraging influences plant growth responses to earthworm foraging.

    PubMed

    Cameron, Erin K; Cahill, James F; Bayne, Erin M

    2014-01-01

    Interactions among the foraging behaviours of co-occurring animal species can impact population and community dynamics; the consequences of interactions between plant and animal foraging behaviours have received less attention. In North American forests, invasions by European earthworms have led to substantial changes in plant community composition. Changes in leaf litter have been identified as a critical indirect mechanism driving earthworm impacts on plants. However, there has been limited examination of the direct effects of earthworm burrowing on plant growth. Here we show a novel second pathway exists, whereby earthworms (Lumbricus terrestris L.) impact plant root foraging. In a mini-rhizotron experiment, roots occurred more frequently in burrows and soil cracks than in the soil matrix. The roots of Achillea millefolium L. preferentially occupied earthworm burrows, where nutrient availability was presumably higher than in cracks due to earthworm excreta. In contrast, the roots of Campanula rotundifolia L. were less likely to occur in burrows. This shift in root behaviour was associated with a 30% decline in the overall biomass of C. rotundifolia when earthworms were present. Our results indicate earthworm impacts on plant foraging can occur indirectly via physical and chemical changes to the soil and directly via root consumption or abrasion and thus may be one factor influencing plant growth and community change following earthworm invasion. More generally, this work demonstrates the potential for interactions to occur between the foraging behaviours of plants and soil animals and emphasizes the importance of integrating behavioural understanding in foraging studies involving plants. PMID:25268503

  2. Root Foraging Influences Plant Growth Responses to Earthworm Foraging

    PubMed Central

    Cameron, Erin K.; Cahill, James F.; Bayne, Erin M.

    2014-01-01

    Interactions among the foraging behaviours of co-occurring animal species can impact population and community dynamics; the consequences of interactions between plant and animal foraging behaviours have received less attention. In North American forests, invasions by European earthworms have led to substantial changes in plant community composition. Changes in leaf litter have been identified as a critical indirect mechanism driving earthworm impacts on plants. However, there has been limited examination of the direct effects of earthworm burrowing on plant growth. Here we show a novel second pathway exists, whereby earthworms (Lumbricus terrestris L.) impact plant root foraging. In a mini-rhizotron experiment, roots occurred more frequently in burrows and soil cracks than in the soil matrix. The roots of Achillea millefolium L. preferentially occupied earthworm burrows, where nutrient availability was presumably higher than in cracks due to earthworm excreta. In contrast, the roots of Campanula rotundifolia L. were less likely to occur in burrows. This shift in root behaviour was associated with a 30% decline in the overall biomass of C. rotundifolia when earthworms were present. Our results indicate earthworm impacts on plant foraging can occur indirectly via physical and chemical changes to the soil and directly via root consumption or abrasion and thus may be one factor influencing plant growth and community change following earthworm invasion. More generally, this work demonstrates the potential for interactions to occur between the foraging behaviours of plants and soil animals and emphasizes the importance of integrating behavioural understanding in foraging studies involving plants. PMID:25268503

  3. Greenhouse-gas emissions from soils increased by earthworms

    NASA Astrophysics Data System (ADS)

    Lubbers, Ingrid M.; van Groenigen, Kees Jan; Fonte, Steven J.; Six, Johan; Brussaard, Lijbert; van Groenigen, Jan Willem

    2013-03-01

    Earthworms play an essential part in determining the greenhouse-gas balance of soils worldwide, and their influence is expected to grow over the next decades. They are thought to stimulate carbon sequestration in soil aggregates, but also to increase emissions of the main greenhouse gases carbon dioxide and nitrous oxide. Hence, it remains highly controversial whether earthworms predominantly affect soils to act as a net source or sink of greenhouse gases. Here, we provide a quantitative review of the overall effect of earthworms on the soil greenhouse-gas balance. Our results suggest that although earthworms are largely beneficial to soil fertility, they increase net soil greenhouse-gas emissions.

  4. Multilevel assessment of Cry1Ab Bt-maize straw return affecting the earthworm Eisenia fetida.

    PubMed

    Shu, Yinghua; Zhang, Yanyan; Cheng, Miaomiao; Zeng, Huilan; Wang, Jianwu

    2015-10-01

    Non-target effects of two varieties of Bacillus thuringiensis (Bt)-maize straw (5422Bt1 [event Bt11] and 5422CBCL [MON810]) return on the Eisenia fetida were investigated by using multilevel assessments, compared to near-isogenic non-Bt-maize (5422). 5422Bt1 straw return had no deleterious effects on adult earthworms and had significantly positive effects on juveniles over three generations. Negative, no, and positive effects on adults treated with 5422CBCL straw were observed in the 1st, 2nd and 3rd generation, respectively. Negative and positive effects were observed on juveniles produced from the 1st- and 2nd-generation adults treated with 5422CBCL straw, respectively. Glutathione peroxidase activity of earthworms from Bt-maize treatments was significantly higher than that of control on the 90th d. Translationally controlled tumour protein (TCTP) and superoxide dismutase (SOD) genes were down-regulated, while annetocin (ANN) expression was up-regulated in 5422Bt1 treatments. TCTP and SOD genes were up-regulated, while ANN and heat shock protein 70 were down-regulated in E. fetida from 5422CBCL treatments. Enzyme-linked immunosorbent assay revealed that Cry1Ab released from 5422Bt1 and 5422CBCL straw degraded rapidly on the 15th and 30th d and had a slow decline in the rest testing time. Cry1Ab concentrations in the soil, casts and guts of earthworm significantly decreased over the course of the experiment. This study was the first to evaluate generational effects of Bt-maize straw return on earthworms under laboratory conditions. The responses of enzymes activity and genes expression may contribute to better understand above different effects of Bt-maize straw return on earthworms from the 1st generation. PMID:26011413

  5. Biological effects of decabromodiphenyl ether (BDE209) and Pb on earthworm (Eisenia fetida) in a soil system.

    PubMed

    Li, Jing; Zhang, Wei; Chen, Lin; Liang, Jun; Lin, Kuangfei

    2015-12-01

    BDE209 and Pb are ubiquitous contaminants at e-waste recycling sites (EWRSs). This study aimed to determine acute and sub-acute toxicity to earthworm Eisenia fetida induced by BDE209 and Pb in natural soil. Results demonstrated that the inhibition of Pb on growth and reproduction of earthworms followed a dose-dependent pattern. Earthworms exposed to 100 mg kg(-1) of BDE209 displayed avoidance responses, while the soil indicated a more obvious decline of habitat function with the increase of Pb level. Comet assay suggested that increasing concentrations of Pb exposure resulted in a gradual increase in the tail length and olive tail moment, which meant that the degree of DNA damage was promoted. BDE209 addition could reduce the damage; therefore the joint effects of both chemicals showed antagonistic. These results revealed that joint exposure (BDE209-Pb) could elicit pronounced biochemical and physiological responses in earthworms, and the DNA damage might be potential molecular biomarker of the two pollutants. PMID:26412261

  6. Test anxiety and performance-avoidance goals explain gender differences in SAT-V, SAT-M, and overall SAT scores.

    PubMed

    Hannon, Brenda

    2012-11-01

    This study uses analysis of co-variance in order to determine which cognitive/learning (working memory, knowledge integration, epistemic belief of learning) or social/personality factors (test anxiety, performance-avoidance goals) might account for gender differences in SAT-V, SAT-M, and overall SAT scores. The results revealed that none of the cognitive/learning factors accounted for gender differences in SAT performance. However, the social/personality factors of test anxiety and performance-avoidance goals each separately accounted for all of the significant gender differences in SAT-V, SAT-M, and overall SAT performance. Furthermore, when the influences of both of these factors were statistically removed simultaneously, all non-significant gender differences reduced further to become trivial by Cohen's (1988) standards. Taken as a whole, these results suggest that gender differences in SAT-V, SAT-M, and overall SAT performance are a consequence of social/learning factors. PMID:23997382

  7. Test anxiety and performance-avoidance goals explain gender differences in SAT-V, SAT-M, and overall SAT scores

    PubMed Central

    Hannon, Brenda

    2013-01-01

    This study uses analysis of co-variance in order to determine which cognitive/learning (working memory, knowledge integration, epistemic belief of learning) or social/personality factors (test anxiety, performance-avoidance goals) might account for gender differences in SAT-V, SAT-M, and overall SAT scores. The results revealed that none of the cognitive/learning factors accounted for gender differences in SAT performance. However, the social/personality factors of test anxiety and performance-avoidance goals each separately accounted for all of the significant gender differences in SAT-V, SAT-M, and overall SAT performance. Furthermore, when the influences of both of these factors were statistically removed simultaneously, all non-significant gender differences reduced further to become trivial by Cohen's (1988) standards. Taken as a whole, these results suggest that gender differences in SAT-V, SAT-M, and overall SAT performance are a consequence of social/learning factors. PMID:23997382

  8. Conditioned suppression/avoidance as a procedure for testing hearing in birds: the domestic pigeon (Columba livia).

    PubMed

    Heffner, Henry E; Koay, Gimseong; Hill, Evan M; Heffner, Rickye S

    2013-06-01

    Although the domestic pigeon is commonly used in learning experiments, it is a notoriously difficult subject in auditory psychophysical experiments, even those in which it need only respond when it detects a sound. This is because pigeons tend to respond in the absence of sound-that is, they have a high false-positive rate-which makes it difficult to determine a pigeon's audiogram. However, false positives are easily controlled in the method of conditioned suppression/avoidance, in which a pigeon is trained to peck a key to obtain food and to stop pecking whenever it detects a sound that signals impending electric shock. Here, we describe how to determine psychophysical thresholds in pigeons using a method of conditioned suppression in which avoidable shock is delivered through a bead chain wrapped around the base of a pigeon's wings. The resulting audiogram spans the range from 2 to 8000 Hz; it falls approximately in the middle of the distribution of previous pigeon audiograms and supports the finding of Kreithen and Quine (Journal of Comparative Physiology 129:1-4, 1979) that pigeons hear infrasound. PMID:23055174

  9. Effects of historic metal(loid) pollution on earthworm communities.

    PubMed

    Lévêque, Thibaut; Capowiez, Yvan; Schreck, Eva; Mombo, Stéphane; Mazzia, Christophe; Foucault, Yann; Dumat, Camille

    2015-04-01

    The effects of metal(loid)s (Pb, Cd, Cu, Zn, As and Sb) from atmospheric fallout on earthworm communities were investigated in a fallow meadow located close to a 60-year-old lead recycling factory. We examined abundance and species diversity as well as the ratio of adult-to-juvenile earthworms, along five 140 m parallel transects. The influence of soil pollution on the earthworm community at the plot scale was put in context by measuring some physico-chemical soil characteristics (OM content, N content, pH), as well as total and bioavailable metal(loid) concentrations. Earthworms were absent in the highly polluted area (concentration from 30,000 to 5000 mg Pb·kg(-1) of dried soil), just near the factory (0-30 m area). A clear and almost linear relationship was observed between the proportion of juvenile versus mature earthworms and the pollution gradient, with a greater proportion of adults in the most polluted zones (only adult earthworms were observed from 30 to 50 m). Apporectodea longa was the main species present just near the smelter (80% of the earthworms were A. longa from 30 to 50 m). The earthworm density was found to increase progressively from five individuals·m(-2) at 30 m to 135 individuals·m(-2) at 140 m from the factory. On average, metal(loid) accumulation in earthworm tissues decreased linearly with distance from the factory. The concentration of exchangeable metal(loid)s in earthworm surface casts was higher than that of the overall soil. Finally, our field study clearly demonstrated that metal(loid) pollution has a direct impact on earthworm communities (abundance, diversity and proportion of juveniles) especially when Pb concentrations in soil were higher than 2050 mg·kg(-1). PMID:25616191

  10. Removal of mercury from soil with earthworms

    SciTech Connect

    Dorfman, D.

    1994-12-31

    Earthworms can live in soils containing high quantities of mercury, lead, and zinc. The worms (Lumbricus terrestris) concentrate these heavy metals in their tissues. The use of these worms to reduce the quantities of mercury and other heavy metals in soils may be practical. In July, 1993, a preliminary study was made using earthworms and soils with differing amounts of mercury, The quantities were 0.0 grams, 0.5 grams, and 1.0 grams of mercury as mercuric chloride. Earthworms were placed into these soils for two or more weeks, then harvested. The worms were rinsed with deionized water, then dissolved in nitric acid. Each sample was prepared for analysis with the addition of HNO{sub 3}, H{sub 2}SO{sub 4}, potassium permanganate, and hydrozylamine hydrochloride. A Jerome Instrument gold foil analyzer was used to determine levels of mercury after volatilizing the sample with stannous chloride. Worms exposed to contaminated soils remove 50 to 1,400 times as much mercury as do worms in control soils. In a hypothetical case, a site contaminated with one pound of mercury, 1,000 to 45,000 worms would be required to reduce mercury levels to background levels in the soil (about 250 ppb). After harvesting worms in contaminated soil they could be dried (90% of their weight is water), and the mercury regained by chemical processes. Soil conducive to earthworm survival is required. This includes a well aerated loamy soil, proper pH (7.0), and periodic watering and feeding. There are several methods of harvesting worms, including flooding and electricity. Large numbers of worms can be obtained from commercial growers.

  11. Determination of arsenic compounds in earthworms

    SciTech Connect

    Geiszinger, A.; Goessler, W.; Kuehnelt, D.; Kosmus, W.; Francesconi, K.

    1998-08-01

    Earthworms and soil collected from six sites in Styria, Austria, were investigated for total arsenic concentrations by ICP-MS and for arsenic compounds by HPLC-ICP-MS. Total arsenic concentrations ranged from 3.2 to 17.9 mg/kg dry weight in the worms and from 5.0 to 79.7 mg/kg dry weight in the soil samples. There was no strict correlation between the total arsenic concentrations in the worms and soil. Arsenic compounds were extracted from soil and a freeze-dried earthworm sample with a methanol/water mixture (9:1, v/v). The extracts were evaporated to dryness, redissolved in water, and chromatographed on an anion- and a cation-exchange column. Arsenic compounds were identified by comparison of the retention times with known standards. Only traces of arsenic acid could be extracted from the soil with the methanol/water (9:1, v/v) mixture. The major arsenic compounds detected in the extracts of the earthworms were arsenous acid and arsenic acid. Arsenobetaine was present as a minor constituent, and traces of dimethylarsinic acid were also detected. Two dimethylarsinoyltribosides were also identified in the extracts by co-chromatography with standard compounds. This is the first report of the presence of dimethylarsinoylribosides in a terrestrial organism. Two other minor arsenic species were present in the extract, but their retention times did not match with the retention times of the available standards.

  12. Teaching basic neurophysiology using intact earthworms.

    PubMed

    Kladt, Nikolay; Hanslik, Ulrike; Heinzel, Hans-Georg

    2010-01-01

    Introductory neurobiology courses face the problem that practical exercises often require expensive equipment, dissections, and a favorable student-instructor ratio. Furthermore, the duration of an experiment might exceed available time or the level of required expertise is too high to successfully complete the experiment. As a result, neurobiological experiments are commonly replaced by models and simulations, or provide only very basic experiments, such as the frog sciatic nerve preparation, which are often time consuming and tedious. Action potential recordings in giant fibers of intact earthworms (Lumbricus terrestris) circumvent many of these problems and result in a nearly 100% success rate. Originally, these experiments were introduced as classroom exercises by Charles Drewes in 1978 using awake, moving earthworms. In 1990, Hans-Georg Heinzel described further experiments using anesthetized earthworms. In this article, we focus on the application of these experiments as teaching tools for basic neurobiology courses. We describe and extend selected experiments, focusing on specific neurobiological principles with experimental protocols optimized for classroom application. Furthermore, we discuss our experience using these experiments in animal physiology and various neurobiology courses at the University of Bonn. PMID:23494516

  13. Teaching Basic Neurophysiology Using Intact Earthworms

    PubMed Central

    Kladt, Nikolay; Hanslik, Ulrike; Heinzel, Hans-Georg

    2010-01-01

    Introductory neurobiology courses face the problem that practical exercises often require expensive equipment, dissections, and a favorable student-instructor ratio. Furthermore, the duration of an experiment might exceed available time or the level of required expertise is too high to successfully complete the experiment. As a result, neurobiological experiments are commonly replaced by models and simulations, or provide only very basic experiments, such as the frog sciatic nerve preparation, which are often time consuming and tedious. Action potential recordings in giant fibers of intact earthworms (Lumbricus terrestris) circumvent many of these problems and result in a nearly 100% success rate. Originally, these experiments were introduced as classroom exercises by Charles Drewes in 1978 using awake, moving earthworms. In 1990, Hans-Georg Heinzel described further experiments using anesthetized earthworms. In this article, we focus on the application of these experiments as teaching tools for basic neurobiology courses. We describe and extend selected experiments, focusing on specific neurobiological principles with experimental protocols optimized for classroom application. Furthermore, we discuss our experience using these experiments in animal physiology and various neurobiology courses at the University of Bonn. PMID:23494516

  14. Assessing the impact of organic and inorganic amendments on the toxicity and bioavailability of a metal-contaminated soil to the earthworm Eisenia andrei.

    PubMed

    González, Verónica; Díez-Ortiz, María; Simón, Mariano; van Gestel, Cornelis A M

    2013-11-01

    Metal-contaminated soil, from the El Arteal mining district (SE Spain), was remediated with organic (6% compost) and inorganic amendments (8% marble sludge) to reduce the mobility of metals and to modify its potential environmental impact. Different measures of metal bioavailability (chemical analysis; survival, growth, reproduction and bioaccumulation in the earthworm Eisenia andrei), were tested in order to evaluate the efficacy of organic and inorganic amendments as immobilizing agents in reducing metal (bio)availability in the contaminated soil. The inorganic amendment reduced water and CaCl2-extractable concentrations of Cd, Pb, and Zn, while the organic amendment increased these concentrations compared to the untreated soil. The inorganic treatment did not significantly reduce toxicity for the earthworm E. andrei after 28 days exposure. The organic amendment however, made the metal-contaminated soil more toxic to the earthworms, with all earthworms dying in undiluted soil and completely inhibiting reproduction at concentrations higher than 25%. This may be due to increased available metal concentrations and higher electrical conductivity in the compost-amended soil. No effects of organic and inorganic treatments on metal bioaccumulation in the earthworms were found and metal concentrations in the earthworms increased with increasing total soil concentrations. PMID:23677751

  15. Earthworm effects on movement of water and solutes in soil

    SciTech Connect

    Trojan, M.D.

    1993-01-01

    The objectives of this study were to determine and model the effects of earthworms on water and solute movement in soil. Microrelief and rainfall effects on water and solute movement were determined in packed buckets inoculated with earthworms (Aporrectodea tuberculata). A solution of Br[sup [minus

  16. A method for assessing sublethal effects of contaminants in soils to the earthworm, Eisenia foetida

    SciTech Connect

    Gibbs, M.H.; Wicker, L.F.; Stewart, A.J.

    1996-03-01

    The authors developed and tested a procedure that allows quantification of the effects of soil contaminants on earthworm (Eisenia foetida) growth and reproduction. The procedure monitors isolated pairs of earthworms and generates a higher ratio of data per organisms than other commonly used procedures. It also incorporates an accurate technique for measuring adult growth, has high sensitivity compared to the Organization for Economic Cooperation and Development (OECD) 14-d acute toxicity test, and is cost effective. The authors applied the method to a variety of soil-testing problems. A food-and-substrate trial using artificial soil demonstrated the sensitivity of the method and the need for food supplementation to stimulate earthworm reproduction. Application of the procedure to assess efficacy of a soil bioremediation technology revealed the advantage of measuring both growth and reproduction and highlighted the usefulness of a single integrated measure of these two responses. The method also was used as a fast-screening analysis for field soils in a large-scale ecological risk assessment. Finally, a reference toxicant, used in dilution series, demonstrated that responses of E. foetida using the authors` method were similar to their responses in the OECD artificial-soil test method. The results of this study indicate that this procedure can be used both for regulatory and compliance needs within the framework of ecological risk assessment.

  17. Determination of biomarkers for polycyclic aromatic hydrocarbons (PAHs) toxicity to earthworm (Eisenia fetida).

    PubMed

    Nam, Tae-Hoon; Jeon, Hwang-Ju; Mo, Hyung-ho; Cho, Kijong; Ok, Yong-Sik; Lee, Sung-Eun

    2015-12-01

    Polycyclic aromatic hydrocarbon (PAH) compounds are persistent, carcinogenic, and mutagenic. When PAHs enter agricultural soils through sewage sludge, they pose an environmental risk to soil organisms, including earthworms. Therefore, we aimed to determine the toxic effects of PAHs on earthworms. Five PAHs were used: fluorene, anthracene, phenanthrene, fluoranthene, and pyrene. Only fluorene and phenanthrene exhibited toxicity (LC50 values 394.09 and 114.02 g L(-1), respectively) against the earthworm Eisenia fetida. None of the other PAHs tested in this study enhanced the mortality of adult earthworm until the concentrations reached to 1000 g L(-1). After exposure to PAHs, acetylcholinesterase (AChE) activity in E. fetida decreased in a concentration-dependent manner, and phenanthrene exhibited the strongest inhibitory effect on AChE, followed by fluorene. Activity of a representative detoxifying enzyme, carboxylesterase, was dramatically reduced in E. fetida exposed to all tested PAHs in comparison with that observed in the control test. The remaining glutathione S-transferase activity significantly decreased in E. fetida after exposure to PAHs. To profile small proteins <20 kDa, SELDI-TOF MS with Q10 ProteinChips was used, and 54 proteins were identified as being significantly different from the control (p = 0.05). Among them, the expressions of three proteins at 4501.8, 4712.4, and 4747.9 m/z were only enhanced in E. fetida exposed to anthracene and pyrene. One protein with 16,174 m/z was selectively expressed in E. fetida exposed to fluorene, phenanthrene, and fluoranthene. These proteins may be potential biomarkers for the five PAHs tested in E. fetida. PMID:25920560

  18. The effect of tributyltin-oxide on earthworms, springtails, and plants in artificial and natural soils.

    PubMed

    Römbke, J; Jänsch, S; Junker, T; Pohl, B; Scheffczyk, A; Schallnass, H-J

    2007-05-01

    Chemical bioavailability in Organisation for Economic Co-operation and Development (OECD) artificial soil can contrast with bioavailability in natural soils and produce ecotoxicologic benchmarks that are not representative of species' exposure conditions in the field. Initially, reproduction and growth of earthworm and Collembolan species, and early seedling growth of a dicotyledonous plant species, in nine natural soils (with a wide range of physicochemical properties) and in OECD soil were evaluated. Soils that supported reproduction and growth of the test species were then used to investigate the toxicity of tributyltin-oxide (TBT-O). Natural soils caused greater toxicity of TBT-O to earthworms (EC(50) values varied from 0.5 to 4.7 mg/kg soil dry weight [dw]) compared with toxicity in OECD soil (EC(50) = 13.4 mg/kg dw). Collembolans were less sensitive to TBT-O than earthworms in natural soils, with EC(50) values ranging from 23.4 to 177.8 mg/kg dw. In contrast, the toxicity of TBT-O to collembolans in OECD soil (EC(50) = 104.0 mg/kg dw) was within the range of EC(50) values in natural soils. Phytotoxicity tests revealed even greater difference between the effects in natural soils (EC(50) values ranged from 10.7 to 189.2 mg/kg dw) and in OECD soil (EC(50) = 535.5 mg/kg dw) compared with results of the earthworm tests. Studies also showed that EC(50) values were a more robust end point compared with EC(10) values based on comparisons of coefficients of variation. These results show that toxicity testing should include studies with natural soils in addition to OECD soil to better reflect exposure conditions in the field. PMID:17380235

  19. Production and characterization of bacterial cellulose by Leifsonia sp. CBNU-EW3 isolated from the earthworm, Eisenia fetida

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A total of five bacterial strains were isolated from earthworm, Eisenia fetida and examined for bacterial cellulose (BC) production in Hestrin–Schramm medium (HS). Among the five strains tested, CBNU-EW3 exhibited excellent BC production and was identified as Leifsonia sp. by 16S rDNA sequence analy...

  20. Trade-offs between nitrous oxide emission and C-sequestration in the soil: the role of earthworms

    NASA Astrophysics Data System (ADS)

    van Groenigen, J.; Lubbers, I. M.; Giannopoulos, G.

    2008-12-01

    The rapidly rising concentrations of the greenhouse gas carbon dioxide (CO2) in the atmosphere has spurred the interest in soils as a potential carbon (C) sink. However, there are many reports indicating that C- sequestration is often negated by elevated emissions of the potent greenhouse gas nitrous oxide (N2O). It is not yet clear what the driving factors behind this trade-off are, nor how it can be avoided. We suggest that earthworm activity may be partly responsible for the trade-off. Earthworm activity is increasingly recognized as being beneficial to C-sequestration through stabilization of SOM. We report experimental results suggesting that they can also lead to strongly elevated N2O-emissions. In a first experiment, dried grass residue (Lolium perenne) was applied at the top of a loamy soil or mixed through the soil, and N2O-emission was followed for three months. Treatments included presence of the epigeic earthworm Lumbricus rubellus and the anecic earthworm Aporrectodea longa. Cumulative N2O-emissions increased significantly for both species. The strongest effect was measured for L. rubellus, where N2O-emissions significantly increased from 55.7 to 789.1 micro g N2O-N kg- 1 soil. This effect was only observed when residue was applied on top of the soil. In a second experiment we determined the effect of epigeic (L. rubellus) and endogeic (Aporrectodea caliginosa) earthworms on N2O-emissions for two different soil types (loam and sand) in the presence of 15N-labeled radish residue (Raphanus sativus subsp. oleiferus). Both species showed significant increases in N2O-emissions, which differed with residue application method and soil type. N2O- emissions were generally larger in loamy soils and the strongest effect was measured for A. caliginosa when residue was mixed into the soil, increasing emissions from 1350.1 to 2223.2 micro g N2O-N kg- 1 soil. L. rubellus only resulted in elevated N2O-emissions when residue was applied on top. These studies make it

  1. Evaluation of a remediation process for lead contaminated soil by toxicity bioassays: Plants and earthworms

    SciTech Connect

    Chana, L.W.; Smith, K.

    1995-12-31

    Soil from a site contaminated with heavy metals (predominantly lead) was treated using the TERRAMET{reg_sign} lead extraction process. Earthworm acute toxicity and plant seed germination/root elongation (SG/RE) bioassays were used to evaluate the toxicity of the soil before treatment (BT), after treatment (AT) and after treatment, followed by rinsing with water, intended to simulate exposure to rainfall (RT). The results showed BT and RT were not toxic to earthworms in a 14-day exposure while AT showed significant toxicity. The LC{sub 50} values for Eisenia and Lumbricus were 44.04 and 28.83 (as % AT soil/test soil mixture), respectively. The phytotoxicity data indicated that all 3 test soils significantly inhibited lettuce SG/RE in a dose-related manner, with AT being the most phytotoxic. In oats, RT had no effect on SG/RE and AT was more toxic than BT. For the two local-site grass seeds tested (blue grama and sideoat grama), the AT soil was the most phytotoxic followed by BT and RT. The results suggest that the soil after this remediation process exerts significant toxicity on both plant and earthworm, but after a rain-simulating rinse, the toxicity is the same as, or less than, the toxicity before treatment. Further studies are in progress to confirm the assumption that the high salt concentrations generated by acidification during the leaching process, followed by neutralization are responsible for the increased toxicity of unrinsed soil in both plant and earthworm.

  2. Chronic mild stress in submissive mice: Marked polydipsia and social avoidance without hedonic deficit in the sucrose preference test.

    PubMed

    Gross, Moshe; Pinhasov, Albert

    2016-02-01

    In the Chronic Mild Stress (CMS) protocol, rodents are exposed to unpredictable stressors to induce anxiety-like behavior and hedonic deficit in the Sucrose Preference test (SPT). Since CMS-induced anxiety- and anhedonic-like behavior may depend upon individual vulnerability to stress, we hypothesized that selectively bred Submissive (Sub) mice would exhibit heightened anxiety- and anhedonic-like behavior, in response to CMS exposure. We anticipated that the testing of Sub mice alongside their Wt counterparts in a battery of behavioral assays would identify parameters most sensitive to CMS effects. To test these assumptions, Sub mice and their outbred Sabra (Wt) counterparts underwent a five-week CMS-SPT regimen. CMS exposure led to reduced preference for sucrose (sucrose-sweetened water as percent of total intake) among both mouse strains (p<0.01 Wt; p<0.05 Sub). However, this effect was attributed to CMS-induced polydipsia, indicated by mice's increased water consumption, (p<0.01 Wt and Sub), without changes in sucrose intake. Furthermore, CMS-exposed Sub mice, but not Wt, demonstrated impaired social exploration in the Three Chamber test (p<0.05) and anxiety-like effects in the Elevated Plus Maze (p<0.05). Moreover, in a separate experiment, social isolation alone was sufficient to induce polydipsia in Sub mice, without affecting Wt mice's drinking behavior. The present findings suggest that the EPM and Three Chamber tests may be valuable complementary measures of CMS effects, alongside the Sucrose Preference test, and introduce the Sub mouse strain for use in study of susceptibility to stress. PMID:26522843

  3. Near infrared spectroscopy for identifying the earthworm's participation to soil macroaggregation

    NASA Astrophysics Data System (ADS)

    Zangerlé, Anne; Hissler, Christophe; Lavelle, Patrick

    2014-05-01

    As ecosystem engineers, earthworms are major actors of soil aggregation, a process that drives the delivery of ecosystem services by soils. However, our inability to identify the origins of different types of macroaggregates found in soils, the macroaggregates persistence in the soil matrix, their degradation rates, and their role in the dynamics of soil organic matter (SOM) and nutrients remain poorly known. Near Infrared Spectroscopy (NIRS) was tested as a tool to discriminate between origins of macroaggregates, collected in the field at the soil surface and in the 25 first cm of the soil. In parallel, NIR spectral signatures of earthworm casts were measured, during the ageing processes of the aggregates. During the first experiment, earthworm casts of unknown origins, collected in the field, were identified by comparing their NIR spectral signatures to the signatures of macroaggregates produced by the same ecosystem engineers in laboratory conditions, living in the same soil. Principal component analysis of NIR spectra permitted us to characterize macroaggregates of each species by a specific spectral signature (p<0.001; total variance explained: 38.3%). The organic matters included in the soil macroaggregates present quantitative and qualitative differences according to the earthworm species that produced them. During the second experiment, realized in laboratory conditions, NIR spectral signatures were measured in subterranean and surface casts of different earthworm species, incubated in controlled laboratory conditions for different periods of time. In parallel, dynamics of total amounts of C and N were assessed in ageing macroaggregates. As casts aged, NIR spectral signatures went through three main stages in the maturation process: (1) rapid changes in the NIR signal during the first 48 h, (2) a maturation period from days 3-30 with much slower change in NIR spectral signatures and (3) a further stage of maturation (days 45-90), where cast spectral

  4. Unique phenotypes in the sperm of the earthworm Eudrilus eugeniae for assessing radiation hazards.

    PubMed

    Yesudhason, Beryl Vedha; Jegathambigai, Jothipandi; Thangasamy, Pon Amutha; Lakshmanan, Durga Devi; Selvan Christyraj, Johnson Retnaraj Samuel; Sathya Balasingh Thangapandi, Emmanuel Joshua Jebasingh; Krishnan, Muthukalingan; Sivasubramaniam, Sudhakar

    2013-06-01

    The earthworm, Eudrilus eugeniae is a segmented worm. It has two pairs of testes whose cells are highly proliferative. It was found that the earthworm, which is irradiated with X-ray, shows the following phenotypic changes in its sperm: fragmented acrosome in the head, break in the tail, and the appearance of zigzag sperm tail. Sperm morphology can be used as a tool to study radiation hazards in local areas. These three phenotypes were not observed in the sperm of worms exposed to different concentration of toxic chemicals such as sodium arsenate, lead acetate, and mercuric chloride. In contrast, exposure of worms to ethidium bromide caused fragmented acrosome in the head of their sperm cells. PMID:23093367

  5. Existential Threat or Dissociative Response? Examining Defensive Avoidance of Point-of-Care Testing Devices Through a Terror Management Theory Framework.

    PubMed

    Dunne, Simon; Gallagher, Pamela; Matthews, Anne

    2015-01-01

    Using a terror management theory framework, this study investigated if providing mortality reminders or self-esteem threats would lead participants to exhibit avoidant responses toward a point-of-care testing device for cardiovascular disease risk and if the nature of the device served to diminish the existential threat of cardiovascular disease. One hundred and twelve participants aged 40-55 years completed an experimental questionnaire. Findings indicated that participants were not existentially threatened by established terror management methodologies, potentially because of cross-cultural variability toward such methodologies. Highly positive appraisals of the device also suggest that similar technologies may beneficially affect the uptake of screening behaviors. PMID:24972015

  6. Diversification patterns in cosmopolitan earthworms: similar mode but different tempo.

    PubMed

    Fernández, Rosa; Novo, Marta; Marchán, Daniel F; Díaz Cosín, Darío J

    2016-01-01

    Comparative phylogeography of widespread species that span the same geographic areas can elucidate the influence of historical events on current patterns of biodiversity, identify patterns of co-vicariance, and therefore aid the understanding of general evolutionary processes. Soil-dwelling animals present characteristics that make them suitable for testing the effect of the palaeogeographical events on their distribution and diversification, such as their low vagility and population structure. In this study, we shed light on the spatial lineage diversification and cladogenesis of two widely-distributed cosmopolitan and invasive earthworms (Aporrectodea rosea and A. trapezoides) in their putative ancestral area of origin, the Western Palearctic, and a few populations in North America. Molecular analyses were conducted on mitochondrial and nuclear markers from 220 (A. rosea) and 198 (A. trapezoides) individuals collected in 56 and 57 localities, respectively. We compared the lineage diversification pattern, genetic variability and cladogenesis in both species. Our findings showed that both species underwent a similar diversification from the Western Mediterranean plates to (i) Northern Europe and (ii) the Iberian Peninsula, establishing their two main lineages. Their diversification was in concordance with the main palaeogeographical events in the Iberian Peninsula and Western Mediterranean, followed by a later colonization of North America from individuals derived exclusively from the Eurosiberian lineage. Their diversification occurred at different times, with the diversification of A. rosea being potentially more ancient. Cladogenesis in both species seems to have been modelled only by the Mediterranean plate shifts, ignoring historical climatic oscillations such as the Messinian salinity crisis. Their high genetic variability, strong population structure, lack of gene flow and stepping-stone-like cladogenesis suggest the existence of different cryptic lineages

  7. Carbaryl-induced behavioural and reproductive abnormalities in the earthworm Metaphire posthuma: a sensitive model.

    PubMed

    Gupta, Shrawan K; Saxena, Prem N

    2003-12-01

    Carbaryl, an N-methyl carbamate insecticide, is used in India to control foliar insects, but, due to soil contamination, it also adversely affects non-target organisms such as earthworms. This paper deals with the toxic effects of carbaryl on the behavioural and reproductive profiles of the earthworm, Metaphire posthuma. Locomotion and geotaxis were significantly affected, even after a 20-minute exposure to 0.125ppm carbaryl. The hatching of cocoons was altered at 0.5ppm, whereas cocoon production was retarded even at 0.125ppm carbaryl. No cocoon production was observed at 2.0ppm carbaryl. Sperm head abnormalities were reported even at the lowest test concentration of 0.125ppm. Wavy head abnormalities were observed at 0.125ppm carbaryl, whereas at 0.25ppm and 0.5ppm, the sperm heads became amorphous and the head nucleus was turned into granules deposited within the wavy head. It is concluded that the earthworm could be used as an ecosystem model for the initial toxicity testing of environmental pollutants. PMID:15560748

  8. Toxic effects of PCDD/Fs mixtures on Eisenia andrei earthworms.

    PubMed

    Belmeskine, Hayet; Haddad, Sami; Vandelac, Louise; Sauvé, Sébastien; Fournier, Michel

    2012-06-01

    The earthworms Eisenia andrei were used to study the toxicity of PCDD/Fs mixtures to earthworms during 28 day of exposure. The experiments were performed on artificial soils contaminated with dioxins at levels of C1 (0.1 ng 2, 3, 7, 8-TCDD/g soil), C2 (1 ng 2, 3, 7, 8-TCDD/g soil) and C3 (1.5 ng 2, 3, 7, 8-TCDD/g soil). Effects of PCDD/Fs on survival, growth rate and immune responses; phagocytosis and NK-like cell activity, were determined. No mortality was observed at the lowest concentration (C1), while mortalities of 10 and 100% were noted at the highest concentrations tested C2 and C3, respectively. A significant reduction in growth rate was obtained at C2 and no effects at C1. Additionally, an inhibition of phagocytic activity and efficiency was observed at higher concentrations. In contrast, an enhancement of NK-like cell activity was shown at lower concentrations. Based on our results, we hypothesize that the PCDD/Fs mixtures tested at levels equal or higher to C2 (1 ng 2378-TCDD/g soil), lead to adverse effects on biotic potential and immune functions in E. andrei earthworms. PMID:22401954

  9. Effects of transgenic Bt corn litter on the earthworm Lumbricus terrestris.

    PubMed

    Zwahlen, C; Hilbeck, A; Howald, R; Nentwig, W

    2003-04-01

    A 200-day study was carried out to investigate the impact of transgenic Bacillus thuringiensis (Bt) corn on immature and adult Lumbricus terrestris in the field and in the laboratory. Another objective of this study was to develop test methods that could be used for standard testing of the impact of transgenic plants on different earthworm species in the field and in the laboratory. For this purpose two different experiments were involved, a laboratory experiment with adult L. terrestris and a field experiment with immature L. terrestris. No lethal effects of transgenic Bt corn on immature and adult earthworms were observed. Immature L. terrestris in the field had a very similar growth pattern when fed either (Bt+) or (Bt-) corn litter. No significant differences in relative weights of (Bt+) and (Bt-) corn-fed adult L. terrestris were observed during the first 160 days of the laboratory trial, but after 200 days adult L. terrestris had a significant weight loss of 18% of their initial weight when fed (Bt+) corn litter compared to a weight gain of 4% of the initial weight of (Bt-) corn-fed earthworms. Further studies are necessary to see whether or not this difference in relative weight was due to the Bt toxin or other factors discussed in the study. Degradation of Cry1Ab toxin in corn residues was significantly slower in the field than at 10 degrees C in the laboratory. Enzyme-linked immunosorbent assay results indicated that earthworms in both experiments were exposed to the Bt toxin throughout the whole experimental time. PMID:12753225

  10. Analysis of genetic diversity in earthworms using DNA markers.

    PubMed

    Sharma, Anshul; Sonah, Humira; Deshmukh, Rupesh K; Gupta, Navneet K; Singh, Nagendra K; Sharma, Tilak R

    2011-01-01

    Earthworms are one of the most important and beneficial macrofauna, and are used extensively in organic farming. Earthworms mediate soil biological regulation systems, and produce biogenic structures. They help to maintain soil structure, water infiltration, and regulate the availability of nutrients assimilated by plants. The objectives of this study were to perform morphological and molecular characterizations of 24 earthworm individuals collected from geographically diverse locations to assess the level of genetic variation. For molecular analysis, the effectiveness of RAPD, ISSR, and Universal rice primers (URPs) markers was investigated to identify polymorphism among 24 isolates of earthworms. A total of 62 molecular markers were used for amplification of genomic DNA of earthworms. Of these, 10 RAPD, 10 ISSR, and 10 URPs markers were used for characterization, which showed 95.7%, 96.7% and 98.3% polymorphism, respectively. The dendrogram, generated from the DNA markers by the unweighted pair group method using arithmetic averages, grouped all the isolates into two main clusters. All Eisenia fetida isolates were clustered in group A, whereas group B included three isolates belonging to Eudrilus eugeniae. Molecular markers allowed a rapid assessment of genetic variation among these closely related isolates of earthworms. These results suggest that molecular markers are a good choice for diversity analysis of earthworm individuals. PMID:21186943

  11. Earthworms increase plant production: a meta-analysis.

    PubMed

    van Groenigen, Jan Willem; Lubbers, Ingrid M; Vos, Hannah M J; Brown, George G; De Deyn, Gerlinde B; van Groenigen, Kees Jan

    2014-01-01

    To meet the challenge of feeding a growing world population with minimal environmental impact, we need comprehensive and quantitative knowledge of ecological factors affecting crop production. Earthworms are among the most important soil dwelling invertebrates. Their activity affects both biotic and abiotic soil properties, in turn affecting plant growth. Yet, studies on the effect of earthworm presence on crop yields have not been quantitatively synthesized. Here we show, using meta-analysis, that on average earthworm presence in agroecosystems leads to a 25% increase in crop yield and a 23% increase in aboveground biomass. The magnitude of these effects depends on presence of crop residue, earthworm density and type and rate of fertilization. The positive effects of earthworms become larger when more residue is returned to the soil, but disappear when soil nitrogen availability is high. This suggests that earthworms stimulate plant growth predominantly through releasing nitrogen locked away in residue and soil organic matter. Our results therefore imply that earthworms are of crucial importance to decrease the yield gap of farmers who can't -or won't- use nitrogen fertilizer. PMID:25219785

  12. Optimal growth condition of earthworms and their vermicompost features during recycling of five different fresh fruit and vegetable wastes.

    PubMed

    Huang, Kui; Xia, Hui; Li, Fusheng; Wei, Yongfen; Cui, Guangyu; Fu, Xiaoyong; Chen, Xuemin

    2016-07-01

    This study aimed to promote vermicomposting performance for recycling fresh fruit and vegetable wastes (FVWs) and to assess microbial population and community of final products. Five fresh FVWs including banana peels, cabbage, lettuce, potato, and watermelon peels were chosen as earthworms' food. The fate test of earthworms showed that 30 g fresh FVWs/day was the optimal loading and the banana peels was harmful for the survival of Eisenia fetida. The followed vermicomposting test revealed lower contents of total carbon and weaker microbial activity in final vermicomposts, relative to those in compared systems without earthworms worked. The leachate from FVWs carried away great amounts of nutrients from reactors. Additionally, different fresh FVWs displayed dissimilar stabilization process. Molecular biological approaches revealed that earthworms could broaden bacterial diversity in their products, with significant greater populations of actinobacteria and ammonia oxidizing bacteria than in control. This study evidences that vermicomposting efficiency differs with the types and loadings of fresh FVWs and vermicomposts are rich in agricultural probiotics. PMID:27184146

  13. Fostering assumption-based stress-test thinking in managing groundwater systems: learning to avoid failures due to basic dynamics

    NASA Astrophysics Data System (ADS)

    Guillaume, Joseph H. A.; El Sawah, Sondoss

    2014-06-01

    Sustainable groundwater resource management can only be achieved if planning processes address the basic dynamics of the groundwater system. Conceptual and distributed groundwater models do not necessarily translate into an understanding of how a plan might operate in reality. Prompted by Australian experiences, `iterative closed-question modelling' has been used to develop a process of iterative dialogue about management options, objectives and knowledge. Simple hypothetical models of basic system dynamics that satisfy agreed assumptions are used to stress-test the ability of a proposed management plan to achieve desired future conditions. Participants learn from models in which a plan succeeds and fails, updating their assumptions, expectations or plan. Their new understanding is tested against further hypothetical models. The models act as intellectual devices that confront users with new scenarios to discuss. This theoretical approach is illustrated using simple one and two-cell groundwater models that convey basic notions of capture and spatial impacts of pumping. Simple extensions can address uncertain climate, managed-aquifer recharge and alternate water sources. Having learnt to address the dynamics captured by these models, participants may be better placed to address local conditions and develop more effective arrangements to achieve management outcomes.

  14. Sewage sludge toxicity assessment using earthworm Eisenia fetida: can biochemical and histopathological analysis provide fast and accurate insight?

    PubMed

    Babić, S; Barišić, J; Malev, O; Klobučar, G; Popović, N Topić; Strunjak-Perović, I; Krasnići, N; Čož-Rakovac, R; Klobučar, R Sauerborn

    2016-06-01

    Sewage sludge (SS) is a complex organic by-product of wastewater treatment plants. Deposition of large amounts of SS can increase the risk of soil contamination. Therefore, there is an increasing need for fast and accurate assessment of SS toxic potential. Toxic effects of SS were tested on earthworm Eisenia fetida tissue, at the subcellular and biochemical level. Earthworms were exposed to depot sludge (DS) concentration ratio of 30 or 70 %, to undiluted and to 100 and 10 times diluted active sludge (AS). The exposure to DS lasted for 24/48 h (acute exposure), 96 h (semi-acute exposure) and 7/14/28 days (sub-chronic exposure) and 48 h for AS. Toxic effects were tested by the measurements of multixenobiotic resistance mechanism (MXR) activity and lipid peroxidation levels, as well as the observation of morphological alterations and behavioural changes. Biochemical markers confirmed the presence of MXR inhibitors in the tested AS and DS and highlighted the presence of SS-induced oxidative stress. The MXR inhibition and thiobarbituric acid reactive substance (TBARS) concentration in the whole earthworm's body were higher after the exposition to lower concentration of the DS. Furthermore, histopathological changes revealed damage to earthworm body wall tissue layers as well as to the epithelial and chloragogen cells in the typhlosole region. These changes were proportional to SS concentration in tested soils and to exposure duration. Obtained results may contribute to the understanding of SS-induced toxic effects on terrestrial invertebrates exposed through soil contact and to identify defence mechanisms of earthworms. PMID:26971513

  15. Invasive Asian Earthworms Negatively Impact Keystone Terrestrial Salamanders.

    PubMed

    Ziemba, Julie L; Hickerson, Cari-Ann M; Anthony, Carl D

    2016-01-01

    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

  16. Invasive Asian Earthworms Negatively Impact Keystone Terrestrial Salamanders

    PubMed Central

    Ziemba, Julie L.

    2016-01-01

    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

  17. Pesticide application to agricultural fields: effects on the reproduction and avoidance behaviour of Folsomia candida and Eisenia andrei.

    PubMed

    Santos, M J G; Ferreira, M F L; Cachada, A; Duarte, A C; Sousa, J P

    2012-11-01

    The objective of this work was to assess the impact of pesticide application to non-target soil organisms simulating what happens following pesticide application in agricultural fields and thus obtaining higher realism on results obtained. For that purpose, three commercial formulations containing the insecticides chlorpyrifos and endosulfan and the herbicide glyphosate were applied to a Mediterranean agricultural field. The soil was collected after spraying and dilution series were prepared with untreated soil to determine the impact of the pesticides on the avoidance behaviour and reproduction of the earthworm Eisenia andrei and the collembolan Folsomia candida. A significant avoidance was observed at the recommended field dose in case of endosulfan by earthworms (60 %) and in case of chlorpyrifos by collembolans (64 %). In addition, both insecticides affected the number of juveniles produced by the earthworms (EC(50) were below the recommended field dose). Glyphosate did not seem to affect either earthworms or collembolans in the recommended field dose. Folsomia candida was more sensitive to pesticide application than Eisenia andrei, what was corroborated by the EC(50) and LC(50) values. In conclusion, insecticides may affect the structure of the soil community by reducing the survival of collembolans and the reproductive capacity of collembolans and earthworms. PMID:22711551

  18. Carbon-Mineral Interactions along an Earthworm Invasion Gradient

    NASA Astrophysics Data System (ADS)

    Lyttle, A.; Yoo, K.; Aufdenkampe, A. K.; Hale, C.; Sebestyen, S. D.

    2010-12-01

    We broadly agree that the interactions of organic matter and minerals contribute to soils’ capacity to store carbon. Such interactions may be controlled by the processes that determine the availability of organic matter and minerals and their physical contacts. One of these processes is bioturbation, and earthworms are the best known organisms that physically mix soils. We are studying carbon mineral interactions along an approximately 200 meter long earthworm invasion transect in a hardwood forest in northern Minnesota. This transect extends from the soils where earthworms are absent to the soils that have been invaded by earthworms for ~30-40 years. Pre-invasion soils have approximately 5 cm thick litter layer, thin (~5 cm) A horizon, silt rich E horizon, and clay-rich Bt horizons. The A and E horizons formed from aeolian deposits, while the clay-rich Bt horizons developed from glacial till. With the advent of earthworm invasion, the litter layer disappears, and the A horizon thickens at the expense of the E horizons. Carbon and nitrogen concentrations in the A and E horizons significantly increased with the advent of earthworm invasion. Simultaneously, minerals’ capacities to complex the organic matter appear to be greater in the soils with active earthworm populations. Based on the data from the two end member soils along the transect, minerals’ specific surface area in the A and E horizons are larger in the earthworm invaded soil than in the pre-invasion soil. Additionally, earthworm invasion rapidly (within < 5 yrs) turned A horizons materials from single grain to strong medium granular structure. Second, significantly greater amounts of Fe oxides and organically-complexed Fe are present in the earthworm invaded soil. While the amounts of organic matter and the minerals’ capacity to complex carbon increase with earthworm invasion, they are also more vigorously mixed. The depth profiles of 210Pb activities from the two end member soils show

  19. Changes in hardwood forest understory plant communities in response to European earthworm invasions.

    PubMed

    Hale, Cindy M; Frelich, Lee E; Reich, Peter B

    2006-07-01

    European earthworms are colonizing earthworm-free northern hardwood forests across North America. Leading edges of earthworm invasion provide an opportunity to investigate the response of understory plant communities to earthworm invasion and whether the species composition of the earthworm community influences that response. Four sugar maple-dominated forest sites with active earthworm invasions were identified in the Chippewa National Forest in north central Minnesota, USA. In each site, we established a 30 x 150 m sample grid that spanned a visible leading edge of earthworm invasion and sampled earthworm populations and understory vegetation over four years. Across leading edges of earthworm invasion, increasing total earthworm biomass was associated with decreasing diversity and abundance of herbaceous plants in two of four study sites, and the abundance and density of tree seedlings decreased in three of four study sites. Sample points with the most diverse earthworm species assemblage, independent of biomass, had the lowest plant diversity. Changes in understory plant community composition were most affected by increasing biomass of the earthworm species Lumbricus rubellus. Where L. rubellus was absent there was a diverse community of native herbaceous plants, but where L. rubellus biomass reached its maximum, the herbaceous-plant community was dominated by Carex pensylvanica and Arisaema triphyllum and, in some cases, was completely absent. Evidence from these forest sites suggests that earthworm invasion can lead to dramatic changes in the understory community and that the nature of these changes is influenced by the species composition of the invading earthworm community. PMID:16922315

  20. Acetylcholinesterase activity in the earthworm Eisenia andrei at different conditions of carbaryl exposure.

    PubMed

    Gambi, Naimj; Pasteris, Andrea; Fabbri, Elena

    2007-05-01

    Recent reports have stressed the need for a better understanding of earthworm biomarker responses. We aimed at investigating acethylcholinesterase (AChE) activity in the earthworm Eisenia andrei after exposure to carbaryl or its commercial formulation Zoril 5 under different in vitro and in vivo experiments. In addition, lysosome membrane stability was assessed by neutral red retention assay in the same experimental conditions. AChE basal Km and Vm values were about 0.16 mM and 41 nmol min(-1) mg protein(-1), respectively. Carbaryl dose-dependently decreased Vmax, while not affecting Km values. Carbaryl reduced earthworm AChE activity within 1 day of in vivo exposure to contaminated filter paper. Tested on soil, carbaryl inhibited AChE with the maximum effect after 3 days; in contrast, lysosome membrane stability of coelomocytes indicated a maximum toxicity after one day, followed by a recovery. AChE inhibition by Zoril 5 was highest after one day, while lysosome membrane stability declined progressively. In all cases, carbaryl dose-dependently decreased Vmax while not affecting Km values. In conclusion, E. andrei AChE activity assessed in vitro is dose-dependently inhibited by the carbamate compound carbaryl, which acts as a pure competitive inhibitor. In vivo experiments suggested that pure and co-formulated carbaryl have different time and/or dose dependent effects on earthworms. Our results further support the use of AChE inhibition as an indicator of pesticide contamination, to be included in a battery of biomarkers for monitoring soil toxicity. PMID:17428735

  1. A filter circuit board for the Earthworm Seismic Data Acquisition System

    USGS Publications Warehouse

    Jensen, Edward Gray

    2000-01-01

    The Earthworm system is a seismic network data acquisition and processing system used by the Northern California Seismic Network as well as many other seismic networks. The input to the system is comprised of many realtime electronic waveforms fed to a multi-channel digitizer on a PC platform. The digitizer consists of one or more National Instruments Corp. AMUX–64T multiplexer boards attached to an A/D converter board located in the computer. Originally, passive filters were installed on the multiplexers to eliminate electronic noise picked up in cabling. It was later discovered that a small amount of crosstalk occurred between successive channels in the digitizing sequence. Though small, this crosstalk will cause what appear to be small earthquake arrivals at the wrong time on some channels. This can result in erroneous calculation of earthquake arrival times, particularly by automated algorithms. To deal with this problem, an Earthworm filter board was developed to provide the needed filtering while eliminating crosstalk. This report describes the tests performed to find a suitable solution, and the design of the circuit board. Also included are all the details needed to build and install this board in an Earthworm system or any other system using the AMUX–64T board. Available below is the report in PDF format as well as an archive file containing the circuit board manufacturing information.

  2. [Specific features of nitrogen transformation in the gut and coprolites of earthworms].

    PubMed

    Umarov, M M; Striganova, B R; Kostin, N V

    2008-01-01

    It has been found that nitrogenase activity in the guts and coprolites of three earthworm species (Lumbricus terrestris, Aporrectodea rosea, and Aporrectodea caliginosa) is one to three orders of magnitude higher than that in the control soil. In A. caliginosa earthworms, the actual nitrogenase activity remains high upon keeping them in soils of different types. However, it reaches a peak in the gut lumen and decreases to a minimum on its wall, which is evidence for a major role of transitional microflora in intestinal nitrogen fixation. Nitrogen fixation activity in freshly excreted coprolites decreases to one-half or one-third of that in the gut and then increases again, reaching a peak on days 3-5 of exposure in the soil. According to the results of multisubstrate testing, the functional diversity of nitrogen-fixing soil microorganisms increases in the course of passage through the earthworm gut. Thus, the microbial community in coprolites retains its functional potential and, within a few days, shows the second peak of activity in the soil. Due to a short-term increase in the rate of nitrogen fixation, coprolites contain a pool of bound amino acids, which become involved in the formation of new humus substances. PMID:19198081

  3. Influence of carbon nanotubes on pyrene bioaccumulation from contaminated soils by earthworms.

    PubMed

    Petersen, Elijah J; Pinto, Roger A; Landrum, Peter F; Weber, Walter J

    2009-06-01

    Increasing production of and application potentials for carbon nanotubes (CNTs) suggest these materials will enter soil and sediment ecosystems in significant masses in upcoming years. This may result in ecological risks, either from the presence of the CNTs themselves or, given their exceptional sorption capacities, from their effects on the fate and accumulation of concurrently present hydrophobic organic chemicals (HOCs). Here we test the influence of additions of single-walled CNTs (SWNTs) and multi-walled CNTs (MWNTs) to two different pyrene-contaminated soils on uptake of this HOC by earthworms (Eisenia foetida). The effects of nanotube additions to the soils were observed to be CNT concentration dependent, with 0.3 mg nanotubes per gram of soil having no impact, while 3.0 mg/g of SWNTs or MWNTs substantially decreased pyrene bioaccumulation from both contaminated soils. The presence of CNTs also affected pyrene elimination rates. After a 14-day exposure to pyrene-spiked soils, earthworms showed enhanced elimination rates in soils amended with 3.0 mg CNT/g but not 0.3 mg CNT/g. These results suggest that the presence of SWNTs or MWNTs in terrestrial ecosystems will have concentration-dependent effects on decreasing HOC accumulation by earthworms in a manner similar to that expected of most "hard" carbons. PMID:19569349

  4. Metals and terrestrial earthworms (Annelida: Oligochaeta)

    USGS Publications Warehouse

    Beyer, W.N.

    1981-01-01

    The toxicity of metals to earthworms and the residues of metals found in earthworms are reviewed. Meta 1 concentrations are rarely high enough to be toxic to worms, but copper may reduce populations in orchards heavily treated with fungicides and in soil contaminated with pig wastes. The metals in some industrial sewage sludges may interfere with using sludge in vermiculture. Storage ratios (the concentration of a metal in worms divided by the concentration in soil) tend to be highest in infertile soil and lowest in media rich in organic matter, such as sewage sludge. Cadmium, gold, and selenium are highly concentrated by worms. Lead concentrations in worms may be very high, but are generally lower than concentrations in soil. Body burdens of both copper and zinc seem to be regulated by worms. Because worms are part of the food webs of many wildlife species, and also because they are potentially valuable feed supplements for domestic animals, the possible toxic effects of cadmium and other metals should be studied. Worms can make metals more available to food webs and can redistribute them in soil.

  5. Earthworms Produce phytochelatins in Response to Arsenic

    PubMed Central

    Lawlor, Alan J.; Bennett, Mark H.; Morris, Ceri A.; Kille, Peter; Svendsen, Claus; Spurgeon, David J.; Bundy, Jacob G.

    2013-01-01

    Phytochelatins are small cysteine-rich non-ribosomal peptides that chelate soft metal and metalloid ions, such as cadmium and arsenic. They are widely produced by plants and microbes; phytochelatin synthase genes are also present in animal species from several different phyla, but there is still little known about whether these genes are functional in animals, and if so, whether they are metal-responsive. We analysed phytochelatin production by direct chemical analysis in Lumbricus rubellus earthworms exposed to arsenic for a 28 day period, and found that arsenic clearly induced phytochelatin production in a dose-dependent manner. It was necessary to measure the phytochelatin metabolite concentrations directly, as there was no upregulation of phytochelatin synthase gene expression after 28 days: phytochelatin synthesis appears not to be transcriptionally regulated in animals. A further untargetted metabolomic analysis also found changes in metabolites associated with the transsulfuration pathway, which channels sulfur flux from methionine for phytochelatin synthesis. There was no evidence of biological transformation of arsenic (e.g. into methylated species) as a result of laboratory arsenic exposure. Finally, we compared wild populations of earthworms sampled from the field, and found that both arsenic-contaminated and cadmium-contaminated mine site worms had elevated phytochelatin concentrations. PMID:24278409

  6. The Design of the Test Format for Tablet Computers in Blended Learning Environments: A Study of the Test Approach-Avoidance Tendency of University Students

    ERIC Educational Resources Information Center

    Kitazawa, Takeshi

    2013-01-01

    This study analyzed effective test formats that utilized tablets for tests in university information basic subjects in blended learning environments. Specifically, three types of test were created: (1) multiple-choice, (2) fill-in-the-blank, and (3) a mixture of multiple-choice and fill-in-the-blank. An analysis focusing on university students'…

  7. Patterns of alpha asymmetry in those with elevated worry, trait anxiety, and obsessive-compulsive symptoms: A test of the worry and avoidance models of alpha asymmetry.

    PubMed

    Smith, Ezra E; Zambrano-Vazquez, Laura; Allen, John J B

    2016-05-01

    Some authors have argued that worry cues lateralization of frontal brain activity leftward, whereas other varieties of avoidance motivation cue lateralization of frontal brain activity rightward. By comparison, more right-than-left parietal activity correlates with anxious arousal. The purpose of the present report was to test two models of brain lateralization and anxiety: one model that proposed that worry correlates with more left-frontal activity and another model that proposed that avoidance motivation (including worry) correlates with more right-frontal activity. Undergraduate students were selected for worry, obsessive-compulsive symptoms, and trait anxiety using self-report questionnaires. A subset of participants also met DSM-IV criteria for Generalized Anxiety Disorder (GAD) or Obsessive-Compulsive Disorder (OCD). Alpha asymmetry and also a global-power-adjusted metric of alpha power were calculated from each participant's resting-state EEG. It was expected that participants with elevated worry and participants meeting criteria for GAD would show more left-than-right frontal activity. In contrast, participants with elevated trait anxiety, obsessive-compulsive symptoms, and those with an OCD diagnosis were expected to exhibit more right-than-left frontal activity. Participants with elevated worry, participants with a GAD diagnosis, and participants with elevated obsessive-compulsive symptoms, had more left frontal activity than low symptom individuals. Those with high scores on trait anxiety, but low worry, had greater right frontal and parietal activity compared to controls. The present results suggest that brain lateralization is not solely related to avoidance motivation, and suggest that facets of anxiety may cut across dimensions not well-represented by DSM-based categories. PMID:26970143

  8. Teachers Avoiding Learners' Avoidance: Is It Possible?

    ERIC Educational Resources Information Center

    Tadayyon, Maedeh; Zarrinabadi, Nourollah; Ketabi, Saeed

    2016-01-01

    Dealing with learners who prefer to take the back seat and avoid classroom participation can be every teacher's nightmare. This lack of participation may cause teacher frustration, and possibly the only way to reduce this lack of participation is to access the concept of avoidance strategy. Avoidance strategy is the abandonment of a classroom task…

  9. Application of microcosmic system for assessment of insecticide effects on biomarker responses in ecologically different earthworm species.

    PubMed

    Velki, Mirna; Hackenberger, Branimir K; Lončarić, Zeljka; Hackenberger, Davorka K

    2014-06-01

    Earthworms from different ecological categories--epigeic Eisenia andrei and Lumbricus rubellus, endogeic Octolasion lacteum and anecic Lumbricus terrestris--were exposed in a microcosmic system to three commonly used insecticides. The effects of the insecticides were evaluated by measuring the following molecular biomarkers-the activities of AChE, CES, CAT, GST and the concentration of GSH. The results showed that environmentally relevant doses of organophosphates dimethoate and pirimiphos-methyl significantly affected the measured biomarkers, whereas pyrethroid deltamethrin did not affect the earthworms at the recommended agricultural dose. Considering the ecological category of earthworms, the results were inhomogeneous and species-specific differences in the biomarker responses were recorded. Since the biomarker responses of the investigated earthworm species were different after exposure to organophosphates in a microcosm compared to the exposure via standardized toxicity tests, two types of species sensitivity should be distinguished-physiological and environmental sensitivity. In addition, the hormetic effect of organophosphates on AChE and CES activities was recorded. The detection of hormesis in a microcosm is of great importance for future environmental research and soil biomonitoring, since in a realistic environment pollutants usually occur at low concentrations that could cause a hormetic effect. The results demonstrate the importance of the application of microcosmic systems in the assessment of the effects of environmental pollutants and the necessity of taking into account the possible differences between physiological and environmental species sensitivity. PMID:24650551

  10. Zaprinast and Rolipram Enhances Spatial and Emotional Memory in the Elevated Plus Maze and Passive Avoidance Tests and Diminishes Exploratory Activity in Naive Mice

    PubMed Central

    Akar, Furuzan; Mutlu, Oguz; Celikyurt, Ipek Komsuoglu; Ulak, Guner; Erden, Faruk; Bektas, Emine; Tanyeri, Pelin

    2014-01-01

    Background Phosphodiesterase (PDE) inhibitors in the central nervous system have been shown to stimulate neuronal functions and increase neurogenesis in Alzheimer disease (AD) patients. Material/Methods The aim of this study was to investigate the effects of zaprinast, a PDE5 inhibitor, and rolipram, a PDE4 inhibitor, on learning and memory in elevated plus maze (EPM) and passive avoidance (PA) tests in naive mice. Male Balb-c mice received short-term treatment with zaprinast (3 and 10 mg/kg) and rolipram (0.05 and 0.1 mg/kg) before the acquisition trial of the EPM and PA tests. The exploratory activity of the animals was also investigated in the Hughes box test. Results Both zaprinast (10 mg/kg) and rolipram (0.1 mg/kg) significantly decreased second-day latency compared to the control group in the EPM test, while only rolipram (0.1 mg/kg) significantly increased second-day latency in the PA test. Both zaprinast (10 mg/kg) and rolipram (0.1 mg/kg) significantly decreased the number of entries to new areas and time spent in new areas in the Hughes box test. Conclusions Our study revealed that both zaprinast and rolipram enhanced spatial memory in EPM, while rolipram seemed to have more emotional memory-enhancing effects in the PA test compared to zaprinast. Both zaprinast and rolipram diminished exploratory activity in the Hughes box test, which can be attributed to the drugs’ anxiogenic effects. PMID:25057848

  11. Toxicity and bioaccumulation of reduced TNT metabolites in the earthworm Eisenia andrei exposed to amended forest soil.

    PubMed

    Lachance, Bernard; Renoux, Agnès Y; Sarrazin, Manon; Hawari, Jalal; Sunahara, Geoffrey I

    2004-06-01

    Soils contaminated with 2,4,6-trinitrotoluene (TNT) and TNT primary reduction products have been found to be toxic to certain soil invertebrates, such as earthworms. The mechanism of toxicity of TNT and of its by-products is still not known. To ascertain if one of the TNT reduction products underlies TNT toxicity, we tested the toxicity and bioaccumulation of TNT reduction products. 2-Amino-4,6-dinitrotoluene (2-ADNT), 4-amino-2,6-dinitrotoluene (4-ADNT), 2,4-diamino-6-nitrotoluene (2,4-DANT) and 2,6-diamino-4-nitrotoluene (2,6-DANT) were tested separately in adult earthworms (Eisenia andrei) following a 14-d exposure to amended sandy loam forest soil. TNT, 4-ADNT, and 2-ADNT were lethal to earthworms (14-d LC(50) were: 580, 531 and 1088 micromol kg(-1), or 132, 105 and 215 mgkg(-1) dry soil, respectively) and gave the following order of toxicity: 4-ADNT>TNT>2-ADNT. Exposure to 2,4-DANT and to 2,6-DANT caused no mortality at 600 micromol kg(-1) or 100 mgkg(-1) dry soil. We found that all four TNT reduction products accumulated in earthworm tissues and 2-ADNT reached the highest levels at 3.0+/-0.3 micromol g(-1) tissue. The 14-d bioaccumulation factors were 5.1, 6.4, 5.1 and 3.2 for 2-ADNT, 4-ADNT, 2,4-DANT and 2,6-DANT, respectively. Results also suggest that some TNT metabolites are at least as toxic as TNT and should be considered when evaluating the overall toxicity of TNT-contaminated soil to earthworms. PMID:15081777

  12. Different sensitivities of biomarker responses in two epigeic earthworm species after exposure to pyrethroid and organophosphate insecticides.

    PubMed

    Velki, Mirna; Hackenberger, Branimir K

    2013-10-01

    In many studies that investigate the toxic effects of pollutants on earthworms, experiments are performed using only one species of earthworms, most commonly the Eisenia species. However, the differences in sensitivities of different earthworm species could potentially lead to an underestimation of environmental aspects of pollutants. Therefore, the aim of this study was to compare the sensitivity of biomarker responses of Eisenia andrei, an epigeic compost species commonly used in laboratory experiments, with those of Lumbricus rubellus, an epigeic species widely distributed in temperate regions. The earthworms were exposed to the three commonly used insecticides: organophosphates dimethoate (0.03, 0.3, and 3 mg kg(-1)) and pirimiphos-methyl (0.02, 0.2, and 2 mg kg(-1)), as well as pyrethroid deltamethrin (0.01, 0.1, and 0.5 mg kg(-1)), for 1 and 15 days using an artificial soil test. The effects of the pesticides were assessed by measuring the activities of acetylcholinesterase (AChE), carboxylesterase (CES), catalase (CAT), glutathione S-transferase (GST) as well as the concentration of glutathione (GSH). The pesticides caused a significant inhibition of AChE and CES activities and significant changes in activities of CAT, GST, and GSH concentration in both earthworm species. A comparison of biomarker responses between E. andrei and L. rubellus showed significant differences; E. andrei proved to be less susceptible to pesticide exposure than L. rubellus. In addition, the results from the filter-paper contact test mortality experiments showed that lethal concentrations were lower for L. rubellus compared with the E. andrei, further showing a greater sensitivity of L. rubellus. The difference in sensitivities of these epigeic species should be taken into account when conducting toxicity studies. PMID:23811990

  13. Checklist of the earthworm fauna of Croatia (Oligochaeta: Lumbricidae).

    PubMed

    Kutuzović, Davorka Hackenberger; Kutuzović, Branimir Hackenberger

    2013-01-01

    A checklist of the Croatian earthworm fauna (Oligochaeta: Lumbricidae) is presented, including published records and authors' personal data. This is the first checklist for Croatia only, with comprehensive information for each earthworm species regarding ecological category, habitat, distribution type and distribution in Croatia. The currently known earthworm fauna of Croatia comprises 68 species belonging to 17 genera, with Octodrilus being the species-richest genus (15 species). Chorologically these species can be allocated to 13 different types of distribution. Nineteen species are endemic of which 10 species are endemic to Croatia and 9 species are endemic to Croatia and neighbouring countries (Italy, Slovenia, Hungary, and Montenegro). The endemic earthworms are distributed in the areas of higher altitudes in the Continental and Alpine biogeographic region, mostly covered with forest or autochtonous vegetation. PMID:26106671

  14. Study on the influential factors of Cd(2+) on the earthworm Eisenia fetida in oxidative stress based on factor analysis approach.

    PubMed

    Zhou, Dongxing; Ning, Yucui; Wang, Bing; Wang, Guangdong; Su, Ye; Li, Lei; Wang, Ye

    2016-08-01

    When earthworms are exposed to pollutants, their antioxidant system will have responses immediately. Consequently earthworms are widely used to monitor various pollutants as a sensitive bio-indicator. However, there are a large number of indices associated with the oxidative stress response. Finding out the key monitoring indices in the stress process becomes a practical demand of the pollution monitoring and warning process. Factor analysis approach is a statistical method that uses a few factors to replace many original factors. This paper is aimed at analyzing and sorting factors related to Cd(2+) on the earthworm Eisenia fetida in oxidative stress. We studied two groups, the short-term test and the long-term test. The former test lasted for ten days, removing an earthworm every day for analysis; The latter test lasted for 30 days, taking out an earthworm every ten days. The Cd(2+) concentration was set at 0, 50, 100, 125, 250 and 500 mg kg(-1), post-clitellum segments of earthworms were chosen to determine SOD, POD, GPX, GST, CAT, VE, MDA and AChE. The results showed that in the short-term group, the main bioindicator associated with oxidative stress reaction was CAT at the exposure time of 1-3 days, at 4-5 days MDA, 6-7 days POD, and GST and GPX at 8th day, CAT at 9-10 days. While with the long-term test, the main bioindicator associated with oxidative stress reaction was GPX. PMID:27219294

  15. Analysis of Eisenia fetida earthworm responses to sub-lethal C60 nanoparticle exposure using (1)H-NMR based metabolomics.

    PubMed

    Lankadurai, Brian P; Nagato, Edward G; Simpson, André J; Simpson, Myrna J

    2015-10-01

    The enhanced production and environmental release of Buckminsterfullerene (C60) nanoparticles will likely increase the exposure and risk to soil dwelling organisms. We used (1)H NMR-based metabolomics to investigate the response of Eisenia fetida earthworms to sub-lethal C60 nanoparticle exposure in both contact and soil tests. Principal component analysis of (1)H NMR data showed clear separation between controls and exposed earthworms after just 2 days of exposure, however as exposure time increased the separation decreased in soil but increased in contact tests suggesting potential adaptation during soil exposure. The amino acids leucine, valine, isoleucine and phenylalanine, the nucleoside inosine, and the sugars glucose and maltose emerged as potential bioindicators of exposure to C60 nanoparticles. The significant responses observed in earthworms using NMR-based metabolomics after exposure to very low concentrations of C60 nanoparticles suggests the need for further investigations to better understand and predict their sub-lethal toxicity. PMID:26024814

  16. Toxicity and bioaccumulation of bromadiolone to earthworm Eisenia fetida.

    PubMed

    Liu, Jing; Xiong, Kang; Ye, Xiaoqing; Zhang, Jianyun; Yang, Ye; Ji, Li

    2015-09-01

    Bromadiolone, a potent second-generation anticoagulant rodenticide, has been extensively used worldwide for the field control of rodents. Invertebrates may be at risk from primary poisoning as a result of bromadiolone bait applications. However, there are few data regarding the toxicity and bioaccumulation of bromadiolone to earthworms. In this study, we reported that bromadiolone was toxic to earthworms at 1mg/kg soil, which is a likely concentration in the field following application of bromadiolone baits. Exposure to bromadiolone resulted in a significant inhibition of earthworm growth. The antioxidant activities of superoxide dismutase and catalase were slightly increased in earthworms, while malondialdehyde content (as a molecular marker indicative of the damage to lipid peroxidation) was dominantly elevated over the duration of exposure. Bromadiolone in soil is bioaccumulative to earthworms. The biota to soil accumulation factors (BSAFs) of bromadiolone were concentration dependent and BSAFs decreased as the level of bromadiolone in soil increased. These results suggest earthworms are not only the potential subject to primary poisoning but also the source of secondary exposure for insectivores and scavengers following application of bromadiolone. PMID:25965004

  17. Activity of earthworm in Latosol under simulated acid rain stress.

    PubMed

    Zhang, Jia-En; Yu, Jiayu; Ouyang, Ying

    2015-01-01

    Acid rain is still an issue of environmental concerns. This study investigated the impacts of simulated acid rain (SAR) upon earthworm activity from the Latosol (acidic red soil). Laboratory experiment was performed by leaching the soil columns grown with earthworms (Eisenia fetida) at the SAR pH levels ranged from 2.0 to 6.5 over a 34-day period. Results showed that earthworms tended to escape from the soil and eventually died for the SAR at pH = 2.0 as a result of acid toxicity. The catalase activity in the earthworms decreased with the SAR pH levels, whereas the superoxide dismutases activity in the earthworms showed a fluctuate pattern: decreasing from pH 6.5 to 5.0 and increasing from pH 5.0 to 4.0. Results implied that the growth of earthworms was retarded at the SAR pH ≤ 3.0. PMID:25351717

  18. Toxicity and bioaccumulation of ethofumesate enantiomers in earthworm Eisenia fetida.

    PubMed

    Xu, Peng; Wang, Yinghuan; Zhang, Yanfeng; Li, Jianzhong; Wang, Huili

    2014-10-01

    Earthworms represent an important food source for many vertebrates and as a result, predators may encounter toxic effects via the food chain from consumption of contaminated worms. Therefore, including an assessment of xenobiotic to worms in risk assessment procedures is advisable. Here we studied the acute toxicity, bioaccumulation and elimination of ethofumesate enantiomers in earthworm, Eisenia fetida, in a soil. A slight difference in toxicity to earthworm between two enantiomers was found, and the calculated LC50 values for (+)-, rac- and (-)-ethofumesate were 4.51, 5.93 and 7.98 μg/cm(2), respectively, indicating that the acute toxicity of ethofumesate enantiomers was enantioselective. Earthworm can uptake ethofumesate but the bioaccumulation curve did not reach the steady state. In the elimination experiment, the concentrations of ethofumesate in earthworm declined following a first-order decay model with a short half life of 1.8d. The bioaccumulation and elimination of ethofumesate in earthworm were both nonenantioselective. In combination with other studies, a linear relationship between Log BSAFs and Log Kow was observed, and the Log BSAFs increased with increasing Log Kow. But the elimination rate did not show any correlation with the Kow value. PMID:25048902

  19. 1H NMR Metabolomics: A New Molecular Level Tool for Assessment of Organic Contaminant Bioavailability to Earthworms in Soil

    NASA Astrophysics Data System (ADS)

    McKelvie, J. R.; Wolfe, D. M.; Celejewski, M. A.; Simpson, A. J.; Simpson, M. J.

    2009-05-01

    At contaminated field sites, the complete removal of polycyclic aromatic hydrocarbons (PAHs) is rarely achieved since a portion of these compounds remain tightly bound to the soil matrix. The concentration of PAHs in soil typically decreases until a plateau is reached, at which point the remaining contaminant is considered non- bioavailable. Numerous soil extraction techniques, including cyclodextrin extraction, have been developed to estimate contaminant bioavailability. However, these are indirect methods that do not directly measure the response of organisms to chemical exposure in soil. Earthworm metabolomics offers a promising new way to directly evaluate the bioavailability and toxicity of contaminants in soil. Metabolomics involves the measurement of changes in small-molecule metabolites, including sugars and amino acids, in living organisms due to an external stress, such as contaminant exposure. The objective of this study was to compare cyclodextrin extraction of soil (a bioavailability proxy) and 1H NMR metabolomic analysis of aqueous earthworm tissue extracts as indicators of contaminant bioavailability. A 30 day laboratory experiment was conducted using phenanthrene-spiked sphagnum peat soil and the OECD recommended earthworm species for toxicity testing, Eisenia fetida. The initial phenanthrene concentration in the soil was 320 mg/kg. Rapid biodegradation of phenanthrene occurred and concentrations decreased to 16 mg/kg within 15 days. After 15 days, phenanthrene biodegradation slowed and cyclodextrin extraction of the soil suggested that phenanthrene was no longer bioavailable. Multivariate statistical analysis of the 1H NMR spectra for E. fetida tissue extracts indicated that the metabolic profile of phenanthrene exposed earthworms differed from control earthworms throughout the 30 day experiment. This suggests that the residual phenanthrene remaining in the soil after 15 days continued to elicit a metabolic response, even though it was not

  20. Earthworm Uptake Routes and Rates of Ionic Zn and ZnO Nanoparticles at Realistic Concentrations, Traced Using Stable Isotope Labeling.

    PubMed

    Laycock, Adam; Diez-Ortiz, Maria; Larner, Fiona; Dybowska, Agnieszka; Spurgeon, David; Valsami-Jones, Eugenia; Rehkämper, Mark; Svendsen, Claus

    2016-01-01

    The environmental behavior of ZnO nanoparticles (NPs), their availability to, uptake pathways by, and biokinetics in the earthworm Lumbricus rubellus were investigated using stable isotope labeling. Zinc isotopically enriched to 99.5% in (68)Zn ((68)Zn-E) was used to prepare (68)ZnO NPs and a dissolved phase of (68)Zn for comparison. These materials enabled tracing of environmentally relevant (below background) NP additions to soil of only 5 mg (68)Zn-E kg(-1). Uptake routes were isolated by introducing earthworms with sealed and unsealed mouthparts into test soils for up to 72 h. The Zn isotope compositions of the soils, pore waters and earthworms were then determined using multiple collector inductively coupled plasma mass spectrometry. Detection and quantification of (68)Zn-E in earthworm tissue was possible after only 4 h of dermal exposure, when the uptake of (68)Zn-E had increased the total Zn tissue concentration by 0.03‰. The results demonstrate that at these realistic exposure concentrations there is no distinguishable difference between the uptake of the two forms of Zn by the earthworm L. rubellus, with the dietary pathway accounting for ∼95% of total uptake. This stands in contrast to comparable studies where high dosing levels were used and dermal uptake is dominant. PMID:26588002

  1. Gene Expression Analysis of CL-20-induced Reversible Neurotoxicity Reveals GABAA Receptors as Potential Target in the Earthworm Eisenia fetida

    PubMed Central

    Gong, Ping; Guan, Xin; Pirooznia, Mehdi; Liang, Chun; Perkins, Edward J.

    2012-01-01

    The earthworm Eisenia fetida is one of the most used species in standardized soil ecotoxicity tests. Endpoints such as survival, growth and reproduction are eco-toxicologically relevant but provide little mechanistic insight into toxicity pathways, especially at the molecular level. Here we applied a toxicogenomic approach to investigate the mode of action underlying the reversible neurotoxicity of hexanitrohexaazaisowurtzitane (CL-20), a cyclic nitroamine explosives compound. We developed an E. fetida-specific shotgun microarray targeting 15119 unique E. fetida transcripts. Using this array we profiled gene expression in E. fetida in response to exposure to CL-20. Eighteen earthworms were exposed for 6 days to 0.2 μg/cm2 of CL-20 on filter paper, half of which were allowed to recover in a clean environment for 7 days. Nine vehicle control earthworms were sacrificed at day 6 and 13, separately. Electrophysiological measurements indicated that the conduction velocity of earthworm medial giant nerve fiber decreased significantly after 6-day exposure to CL-20, but was restored after 7 days of recovery. Total RNA was isolated from the four treatment groups including 6-day control, 6-day exposed, 13-day control and 13-day exposed (i.e. 6-day exposure followed by 7-day recovery), and was hybridized to the 15K shot-gun oligo array. Statistical and bioinformatic analyses suggest that CL-20 initiated neurotoxicity by non-competitively blocking the ligand-gated GABAA receptor ion channel, leading to altered expression of genes involved in GABAergic, cholinergic, and Agrin-MuSK pathways. In the recovery phase, expression of affected genes returned to normality, possibly as a result of autophagy and CL-20 dissociation/metabolism. This study provides significant insights into potential mechanisms of CL-20-induced neurotoxicity and the recovery of earthworms from transient neurotoxicity stress. PMID:22191394

  2. Construction of an electrical device for sampling earthworm populations in the field

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Well-known methods for estimating earthworm population densities range from laborious handsorting through chemical applications to electrical extraction. Of these methods, only the electrical extraction allows for sampling of earthworms without detrimental soil disturbance or contamination. However,...

  3. Organochlorine insecticide residues in soil and earthworms in the Delhi area, India, August-October 1974

    SciTech Connect

    Yadav, D.V.; Mittal, P.K.; Agarwal, H.C.; Pillai, M.K.

    1981-09-01

    DDT residues in soil and earthworms from 50 sites in Delhi were monitored. DDT was detected in all but two samples each of soil and earthworms. Among DDT residues, p,p'-DDE was most common and was found in 48 samples each of soil and earthworms; p,p'-DDT was detected in only 43 soil samples and 46 earthworm samples. p,p'-TDE and o,p'-DDT were also present in smaller concentrations in 29 and 15 soil samples and in 43 and 25 earthworm samples, respectively. Maximum total DDT concentration of 2.6 ppm was detected in the soil from Durga Nagar in the vicinity of a DDT factory. The highest concentration of 37.7 ppm total DDT in earthworms was also obtained from the same site. The maximum concentration factor found in the earthworms was 551. The total DDT concentration in the earthworms and soil showed significant correlation.

  4. Soil and elemental mixing rates across an earthworm invasion chronosequence

    NASA Astrophysics Data System (ADS)

    Resner, K. E.; Yoo, K.; Lyttle, A.; Aufdenkampe, A. K.; Sebestyen, S. D.

    2012-12-01

    Burrowing soil fauna significantly contribute to earth surface processes. In particular, earthworms are well known for their ability to move large masses of soil through ingestion and burrowing activities. Over the past decades, humans have increased the geographic range of earthworms through agricultural and recreational activities, exacerbating their invasion into soils devoid of native earthworms since the Last Glacial Maximum. Invasive earthworms, by mixing soils, have substantially altered forest floor ecology and soil morphology. Though the depth extent of mixing can be inferred from altered soil horizonation, mixing rates of various elements in earthworm invaded soils have not previously been calculated. The earthworm invasion chronosequence in a sugar maple forest in Northern Minnesota provides an ideal outdoor laboratory to understand the relationships between dynamics of invasive earthworm populations and soil elemental mixing rates. In this study we used 137-Cs as a tracer for soil mixing due to its strong adsorption to clays and organic matter and its atmospheric origin. Least invaded soils show high 137-Cs activity in the upper 5 centimeters which quickly disappears with depth, while heavily invaded soils show a greater depth reach and homogenized depth profiles of 137-Cs activity. Along the invasion gradient, the depth profiles of many elements are consistent with 137-Cs activities. Currently, a mass balance equation is being combined with 137-Cs activities and total elemental chemistry to determine mixing rates of major elements: Fe, Si, Al and biologically important: Ca, Mg, and P. It is also evident that mixing alone cannot explain the invasive earthworms' impacts on depth profiles of several elements. Geochemical mass balance calculations show a reduction of Ca, Mg, and K in 0-7cm depths. The loss of Ca from the biologically active zone may have ecological consequences. In contrast, we found greater contents of Fe and Al and dithionite

  5. Earthworm populations of highly metal-contaminated soils restored by fly ash-aided phytostabilisation.

    PubMed

    Grumiaux, Fabien; Demuynck, Sylvain; Pernin, Céline; Leprêtre, Alain

    2015-03-01

    Highly metal contaminated soils found in the North of France are the result of intense industrial past. These soils are now unfit for the cultivation of agricultural products for human consumption. Solutions have to be found to improve the quality of these soils, and especially to reduce the availability of trace elements (TEs). Phytostabilisation and ash-aided phytostabilisation applied since 2000 to an experimental site located near a former metallurgical site (Metaleurop-Nord) was shown previously as efficacious in reducing TEs mobility in soils. The aim of the study was to check whether this ten years trial had influenced earthworm communities. This experimental site was compared to plots located in the surroundings and differing by the use of soils. Main results are that: (1) whatever the use of soils, earthworm communities are composed of few species with moderate abundance in comparison with communities found in similar habitats outside the TEs-contaminated area, (2) the highest abundance and specific richness (4-5 species) were observed in afforested plots with various tree species, (3) ash amendments in afforested plots did not increase the species richness and modified the communities favoring anecic worms but disfavoring epigeic ones. These findings raised the questions of when and how to perform the addition of ashes firstly, to avoid negative effects on soil fauna and secondly, to keep positive effects on metal immobilization. PMID:25499051

  6. Acute toxicity of 2,4,6-trinitrotoluene in earthworm (Eisenia andrei).

    PubMed

    Robidoux, P Y; Hawari, J; Thiboutot, S; Ampleman, G; Sunahara, G I

    1999-11-01

    2,4,6-Trinitrotoluene (TNT) is an worldwide recalcitrant environmental contaminant and is toxic to a number of organisms including humans. This study examines the acute effects (lethal and biomass changes) of TNT on the oligochaetes species Eisenia andrei, using the 3-day filter paper, and the 7- and 14-day direct contact spiked soil (OECD artificial and forest soil) toxicity tests. Studies using the filter paper test indicated that the lethality of TNT could be detected in the range 1.5 to 14.2 microg/cm(2), with significant biomass (body weight) changes occurring at the lowest concentration. Acute effects (lethality) could not be measured when earthworms were placed on filter paper containing a saturated aqueous solution of TNT. This may indicate that with these exposure conditions, TNT may have been adsorbed to the filter paper, and that this matrix should be saturated with TNT before becoming available to the earthworms. Spiked soil toxicity tests indicated that the E. andrei lethality by TNT was >1.5 times higher when earthworms were exposed to TNT-spiked forest soil (LOEC:260 mg/kg; LC(50) 14 days 222.4 mg/kg) than to spiked OECD artificial soil (LOEC:420 mg/kg; LC(50) 14 days: 364.9 mg/kg). The sublethal effect on biomass change at the selected TNT concentrations in soil was not significant compared to controls. Results indicate that the bioanalytical methods described in this article could be used as TNT toxicity assessment tools. This soil quality test method gives valuable information for the screening of soil toxicity. PMID:10581125

  7. Exotic Earthworm Influence on Nitrogen Cycling in FACE Forest Soils

    NASA Astrophysics Data System (ADS)

    Top, S. M.; Filley, T. R.

    2010-12-01

    Exotic earthworm invasion in northern North American forests has the potential to significantly alter nitrogen and carbon cycling in forest soils, through litter layer losses, loss of organic horizon, and changes in fine root density. Earthworm influence on nitrogen cycling is currently being investigated in the free-air CO2 enrichment (FACE) sites at Rhinelander, WI. Because of the 13C depleted CO2 used in the FACE experiment and a 15N addition to the soil, this system affords an ideal opportunity to determine the impact of earthworm activity on soil organic matter dynamics by tracking the relative abundance and stable isotope compositions of biopolymers (amino acids, etc.) isolated in earthworms fecal pellets and soils. The 15N and 13C isotope composition of earthworm fecal matter from epigeic (litter and organic matter horizon dwelling) and endogeic (predominantly mineral soil dwelling) species highlighted their distinct role in litter, surface soil, and deeper soil movement through the soil. Specifically, endogeic fecal matter exhibited a lower uptake of FACE-derived C and a more enriched 15N signal. Nitrogen content of soil between the control and elevated CO2 treatments is not significantly different; however, elevated CO2 treatments exhibited relative depletion in both the soil and root 15N with respect to controls. The loss of 15N in the roots and the top 5 cm of the soil under elevated CO2, suggests that there is greater cycling power with increased below ground productivity and earthworm activity under elevated CO2, as higher abundances of earthworms exist in the elevated CO2 treatments. Amino acid extractions from the soil and fecal matter are ongoing and will help clarify the details regarding molecular nitrogen cycling.

  8. Effects of gypsum on trace metals in soils and earthworms.

    PubMed

    Chen, Liming; Kost, Dave; Tian, Yongqiang; Guo, Xiaolu; Watts, Dexter; Norton, Darrell; Wolkowski, Richard P; Dick, Warren A

    2014-01-01

    Mined gypsum has been beneficially used for many years as an agricultural amendment. A large amount of flue gas desulfurization (FGD) gypsum is produced by removal of SO from flue gas streams when fuels with high S content are burned. The FGD gypsum, similar to mined gypsum, can enhance crop production. However, information is lacking concerning the potential environmental impacts of trace metals, especially Hg, in the FGD gypsum. Flue gas desulfurization and mined gypsums were evaluated to determine their ability to affect concentrations of Hg and other trace elements in soils and earthworms. The study was conducted at four field sites across the United States (Ohio, Indiana, Alabama, and Wisconsin). The application rates of gypsums ranged from 2.2 Mg ha in Indiana to 20 Mg ha in Ohio and Alabama. These rates are 2 to 10 times higher than typically recommended. The lengths of time from gypsum application to soil and earthworm sampling were 5 and 18 mo in Ohio, 6 mo in Indiana, 11 mo in Alabama, and 4 mo in Wisconsin. Earthworm numbers and biomass were decreased by FGD and mined gypsums in Ohio. Among all the elements examined, Hg was slightly increased in soils and earthworms in the FGD gypsum treatments compared with the control and the mined gypsum treatments. The differences were not statistically significant except for the Hg concentration in the soil at the Wisconsin site. Selenium in earthworms in the FGD gypsum treatments was statistically higher than in the controls but not higher than in the mined gypsum treatments at the Indiana and Wisconsin sites. Bioaccumulation factors for nondepurated earthworms were statistically similar or lower for the FGD gypsum treatments compared with the controls for all elements. Use of FGD gypsum at normal recommended agricultural rates seems not to have a significant impact on concentrations of trace metals in earthworms and soils. PMID:25602559

  9. Influence of temperature on the toxicity of zinc to the earthworm Eisenia fetida

    SciTech Connect

    Spurgeon, D.J.; Tomlin, M.A.; Hopkin, S.P.

    1997-02-01

    A range of toxicity tests have been proposed to assess the potential hazards of pollutants to earthworms. Of these, the two acute toxicity tests using Eisenia fetida recommended by the OECD and EEC have become routinely used in the risk assessment and regulation of new and existing chemicals. In addition to the acute tests, procedures have also been proposed for measuring the sub-lethal effects of chemicals on parameter such as reproduction and weight change. In both the lethal and sub-lethal toxicity tests developed with worms, attempts have been made to standardise test conditions to allow results from different laboratories to be directly compared. However, variability in exposure conditions and responses are fundamental to determine the effects of pollutants under natural conditions. In the field, conditions such as light, moisture availability, pH, temperature and humidity all fluctuate over time. Such variations affect both the sensitivity and exposure of individuals to toxic chemicals. Hence when evaluating the potential effects of pollutants, it may be important to known how changes in test conditions influence toxicity. This study assessed the effects of different temperatures on the lethal and sub-lethal toxicity of zinc for the earthworm Eisenia fetida. 23 refs., 1 fig., 1 tab.

  10. Investigation of the toxicokinetics of petroleum hydrocarbon distillates with the earthworm Eisenia andrei.

    PubMed

    Cermak, Janet; Stephenson, Gladys; Birkholz, Detlef; Dixon, D George

    2013-04-01

    The Canada-wide standards for petroleum hydrocarbons in soils regulate petroleum hydrocarbons based on four distillate ranges: F1 (C6-C10), F2 (>C10-C16), F3 (>C16-C34), and F4 (>C34). Previous toxicity tests with earthworms and F2, as well as two subfractions of F3, F3a (>C16-C23) and F3a (>C23-C34), indicate that test durations might not be sufficiently long to reach threshold effect concentrations, likely because of the differing toxicokinetics for each distillate. A study was conducted to determine the toxicokinetics of both aliphatic and aromatic fractions of F2, F3a, and F3b with the earthworm Eisenia andrei. Peak accumulation curves were observed for F2 aliphatics and aromatics and F3a aromatics, likely as a result of changes in exposure concentration over the test duration via loss or a decrease in the bioavailable fraction. Biota-soil accumulation factors were >1 for total F2 aliphatics and aromatics and F3a aromatics as well as for several individual polyaromatic hydrocarbons for each distillate. Aromatics were disproportionately accumulated over aliphatics and were the main contributors to toxicity; therefore, aromatics and aliphatics should be regulated separately. The toxicokinetics were used to interpret previous toxicity data. Higher molecular weight distillates need longer-than-standard test durations to determine toxicity, so toxicity test results from fixed, standard-duration tests are not strictly comparable for these petroleum distillates. PMID:23364619

  11. Earthworm species influence on carbon-mineral association in a sugar maple forest in northern Minnesota

    NASA Astrophysics Data System (ADS)

    Lyttle, A.; Yoo, K.; Aufdenkampe, A. K.; Hale, C. M.; Sebestyen, S. D.

    2011-12-01

    Non-native European earthworms are invading previously earthworm-free hardwood forests in the northern Great Lakes Region. Whereas earthworms' impacts on soil morphology and geochemical properties have been well documented in agricultural settings, the role of earthworms in biogeochemical cycles of undisturbed forests remains poorly understood. The forest soils that were recently invaded by exotic earthworms, therefore, provide a unique opportunity to understand how and how much earthworms contribute to biogeochemistry of non-agricultural environments. Increased degree and extent of soil mixing is one of the better known consequences of the earthworm invasion. Our hypothesis is that invasive earthworms positively affect carbon (C) stabilization by enhancing contacts between organic matter and minerals. We are studying C-mineral complexation along a well-established earthworm chronosequence in a sugar maple forest in northern Minnesota. We have observed changes in total earthworm biomass, A horizon C storage, and total specific surface area (SSA) of minerals as the invasion progresses. Because each earthworm species has different feeding and dwelling habits, biogeochemical imprints of the invasion reflect not only earthworms' biomass but also their species composition. All earthworm species show an increase in their biomass with greater time length since the invasion, though epigeic earthworms tend to be the pioneer species. As the total earthworm biomass increases, we find greater incorporation of organic C into the A horizon; the O horizon thickness decreases from 8 to 0 cm as the A horizon thickens from ~5 cm to ~12 cm. While leaf litter biomass is negatively correlated with total earthworm biomass, dramatic decreases in litter biomass are coupled with considerable increases in the biomass of epi-endogeic species. Despite the general decrease in C storage in the A horizon with greater degree of invasion, the storages fluctuate along the transect because

  12. CB1 receptors in the formation of the different phases of memory-related processes in the inhibitory avoidance test in mice.

    PubMed

    Kruk-Slomka, Marta; Biala, Grażyna

    2016-03-15

    The endocannabinoid system, through the cannabinoid type 1 (CB1) and 2 (CB2) receptors modulates many physiological functions, including different aspects of memory-related processes. The aim of the present experiments was to explore the role of the endocannabinoid system, through CB1 receptors in the different stages of short-term (acquisition, retention and retrieval) and long-term (acquisition, consolidation and retrieval) memory-related responses, using the inhibitory avoidance (IA) test in mice. Our results revealed that an acute injection of oleamide (10 and 20mg/kg), a CB1 receptor agonist, impairs the short-term or/and long-term acquisition, retention/consolidation, retrieval memory and learning processes in the IA test in mice. In turn, in this test an acute injection of AM 251 (1 and 3mg/kg), a CB1 receptor antagonist, improves the short-term or/and long-term memory stages, described above. Moreover, this memory impairment induced by effective dose of oleamide (20mg/kg) is reversed by non-effective dose of AM 251 (0.25mg/kg) in the IA task, which proves the selectivity of oleamide to CB1 receptors and confirms that the CB1 receptor-related mechanism is one of the possible mechanisms, responsible for memory and learning responses. Obtained results provide clear evidence that the endocannabinoid system, through CB1 receptors, participates in the different stages of short- and long-term memory-related behavior. This knowledge may open in the future new possibilities for the development of CB-based therapies, especially for memory impairment human disorders. PMID:26711911

  13. Combined effects of soil moisture and carbaryl to earthworms and plants: simulation of flood and drought scenarios.

    PubMed

    Lima, Maria P R; Soares, Amadeu M V M; Loureiro, Susana

    2011-07-01

    Studying tolerance limits in organisms exposed to climatic variations is key to understanding effects on behaviour and physiology. The presence of pollutants may influence these tolerance limits, by altering the toxicity or bioavailability of the chemical. In this work, the plant species Brassica rapa and Triticum aestivum and the earthworm Eisenia andrei were exposed to different levels of soil moisture and carbaryl, as natural and chemical stressors, respectively. Both stress factors were tested individually, as well as in combination. Acute and chronic tests were performed and results were discussed in order to evaluate the responses of organisms to the combination of stressors. When possible, data was fitted to widely employed models for describing chemical mixture responses. Synergistic interactions were observed in earthworms exposed to carbaryl and drought conditions, while antagonistic interactions were more representative for plants, especially in relation to biomass loss under flood-simulation conditions. PMID:21514022

  14. Toxicity of sodium tungstate to earthworm, oat, radish, and lettuce.

    PubMed

    Bamford, Josie E; Butler, Alicia D; Heim, Katherine E; Pittinger, Charles A; Lemus, Ranulfo; Staveley, Jane P; Lee, K Brian; Venezia, Carmen; Pardus, Michael J

    2011-10-01

    Due to unknown effects of the potential exposure of the terrestrial environment to tungsten substances, a series of toxicity studies of sodium tungstate (Na(2) WO(4) ) was conducted. The effect on earthworm (Eisenia fetida) survival and reproduction was examined using Organisation for Economic Co-operation and Development (OECD) Guideline 222. No effect on either endpoint was seen at the highest concentration tested, resulting in a 56-d no-observed-effect concentration (NOEC) of ≥586 mg tungsten/kg dry soil (nominal concentrations). The effect of sodium tungstate on emergence and growth of plant species was examined according to OECD Guideline 208: oat (Avena sativa), radish (Raphanus sativus), and lettuce (Lactuca sativa). No effects on emergence, shoot height, and dry shoot weight were observed in oats exposed to the highest concentration, resulting in a 21-d NOEC of ≥586 mg tungsten/kg dry soil. The NOECs for radish and lettuce were 65 and 21.7 mg tungsten/kg dry soil (nominal concentrations), respectively. Respective 21-d median effective concentration values (EC50) for radish and lettuce were >586 and 313 mg tungsten/kg dry soil (based on shoot height) (confidence level [CL] -8.5-615); EC25 values were 152 (CL 0-331) and 55 (CL 0-114) mg tungsten/kg dry soil. Results are consistent with the few other tungsten substance terrestrial toxicity studies in the literature. PMID:21805499

  15. Fate and Uptake of Pharmaceuticals in Soil–Earthworm Systems

    PubMed Central

    2014-01-01

    Pharmaceuticals present a potential threat to soil organisms, yet our understanding of their fate and uptake in soil systems is limited. This study therefore investigated the fate and uptake of 14C-labeled carbamazepine, diclofenac, fluoxetine, and orlistat in soil–earthworm systems. Sorption coefficients increased in the order of carbamazepine < diclofenac < fluoxetine < orlistat. Dissipation of 14C varied by compound, and for orlistat, there was evidence of formation of nonextractable residues. Uptake of 14C was seen for all compounds. Depuration studies showed complete elimination of 14C for carbamazepine and fluoxetine treatments and partial elimination for orlistat and diclofenac, with greater than 30% of the 14C remaining in the tissue at the end of the experiment. Pore-water-based bioconcentration factors (BCFs), based on uptake and elimination of 14C, increased in the order carbamazepine < diclofenac < fluoxetine and orlistat. Liquid chromatography–tandem mass spectrometry and liquid chromatography–Fourier transform mass spectrometry indicated that the observed uptake in the fluoxetine and carbamazepine treatments was due to the parent compounds but that diclofenac was degraded in the test system so uptake was due to unidentifiable transformation products. Comparison of our data with outputs of quantitative structure−activity relationships for estimating BCFs in worms showed that these models tend to overestimate pharmaceutical BCFs so new models are needed. PMID:24762061

  16. Laboratory Protocol for Measuring the Bioaccumulation of Mercury by Earthworms

    NASA Astrophysics Data System (ADS)

    Steffy, D.; Nichols, A.; McLaughlin, A.

    2007-12-01

    Protocol was developed for a series of laboratory tests to determine if Canadian earthworms ( Lumbricus terrestris) can hyperaccumulate mercury from the soil in which they live. Two batches of 300 hundred worms each were measured for mercury uptake by establishing 3 populations (one control and two of known contamination). Populations were sampled every two weeks. Worm lengths were measured as an indicator of worm age and health. Worm tissue was processed by a modified EPA Method 7470 consisting of freeze drying, vacuum extraction, oxidation and acid extraction of the mercury. Each sample needed 2.000 g dry weight of worm tissue required 5 to 6 worms to be homogenized. Mercury concentration in the extraction fluid was measured by a CETAC M-6100 cold vapor mercury analyzer with an ASX-400 Autosampler having a method detection limit of 0.05 ppb. QA/QC activities such as calibration of instrumentation, spike samples, blank samples, reagent control samples, triplicate samples, and standard samples ensure acurate and precise measurements of mercury levels in tissue samples.

  17. Bioaccumulation of total mercury in the earthworm Eisenia andrei.

    PubMed

    Le Roux, Shirley; Baker, Priscilla; Crouch, Andrew

    2016-01-01

    Earthworms are a major part of the total biomass of soil fauna and play a vital role in soil maintenance. They process large amounts of plant and soil material and can accumulate many pollutants that may be present in the soil. Earthworms have been explored as bioaccumulators for many heavy metal species such as Pb, Cu and Zn but limited information is available for mercury uptake and bioaccumulation in earthworms and very few report on the factors that influence the kinetics of Hg uptake by earthworms. It is known however that the uptake of Hg is strongly influenced by the presence of organic matter, hence the influence of ligands are a major factor contributing to the kinetics of mercury uptake in biosystems. In this work we have focused on the uptake of mercury by earthworms (Eisenia andrei) in the presence of humic acid (HA) under varying physical conditions of pH and temperature, done to assess the role of humic acid in the bioaccumulation of mercury by earthworms from soils. The study was conducted over a 5-day uptake period and all earthworm samples were analysed by direct mercury analysis. Mercury distribution profiles as a function of time, bioaccumulation factors (BAFs), first order rate constants and body burden constants for mercury uptake under selected conditions of temperature, pH as well as via the dermal and gut route were evaluated in one comprehensive approach. The results showed that the uptake of Hg was influenced by pH, temperature and the presence of HA. Uptake of Hg(2+) was improved at low pH and temperature when the earthworms in soil were in contact with a saturating aqueous phase. The total amount of Hg(2+) uptake decreased from 75 to 48 % as a function of pH. For earthworms in dry soil, the uptake was strongly influenced by the presence of the ligand. Calculated BAF values ranged from 0.1 to 0.8. Mercury uptake typically followed first order kinetics with rate constants determined as 0.2 to 1 h(-1). PMID:27347466

  18. Use of plant and earthworm bioassays to evaluate remediation of soil from a site contaminated with polychlorinated biphenyls

    SciTech Connect

    Meier, J.R.; Chang, L.W.; Meckes, M.C.; Smith, M.K.; Jacobs, S.; Torsella, J.

    1997-05-01

    Soil from a site heavily contaminated with polychlorinated biphenyls (PCBs) was treated with a pilot-scale, solvent extraction technology. Bioassays in earthworms and plants were used to examine the efficacy of the remediation process for reducing the toxicity of the soil. The earthworm toxicity bioassays were the 14-d survival test and 21-d reproduction test, using Lumbricus terrestris and Eisenia fetida andrei. The plant bioassays included phytotoxicity tests for seed germination and root elongation in lettuce and oats, and a genotoxicity test (anaphase aberrations) in Allium cepa (common onion). Although the PCB content of the soil was reduced by 99% (below the remediation goal), toxicity to earthworm reproduction remained essentially unchanged following remediation. Furthermore, phytotoxicity and genotoxicity were higher for the remediated soil compared to the untreated soil. The toxicity remaining after treatment appeared to be due to residual solvent introduced during the remediation process, and/or to heavy metals or other inorganic contaminants not removed by the treatment. Mixture studies involving isopropanol and known toxicants indicated possible synergistic effects of the extraction solvent and soil contaminants. The toxicity in plants was essentially eliminated by a postremediation, water-rinsing step. These results demonstrate a need for including toxicity measurements in the evaluation of technologies used in hazardous waste site remediations, and illustrate the potential value of such measurements for making modifications to remediation processes.

  19. A new and sensitive method for measuring in vivo and in vitro cytotoxicity in earthworm coelomocytes by flow cytometry.

    PubMed

    Kwak, Jin Il; Kim, Shin Woong; An, Youn-Joo

    2014-10-01

    This study describes a new and sensitive method for measuring the in vivo and in vitro cytotoxicity of 2 earthworm species, Eisenia andrei and Perionyx excavatus, exposed to copper. Specifically, we measured the number of coelomocyte cells that were affected by copper following in vivo and in vitro exposure by flow cytometry, after calcein acetoxymethyl ester (calcein-AM) staining. We found that the coelomocyte viability of both earthworm species was noticeably reduced in the in vivo cytotoxicity test at concentrations of 100mg/kg copper in dry soil. However, pathological symptoms, such as mucous secretion and bleeding, swelling, thinning, and fragmentation, and burrowing symptoms were not evident following exposure to copper levels of <400mg/kg dry soil. In conclusion, the present study demonstrates that calcein-AM is a more sensitive test of earthworm coelomocyte cytotoxicity compared to the traditional individual level toxicity test. Therefore, this test could be used to detect low levels of metal contamination in soils. PMID:25127522

  20. Comparative toxicity of pentachlorophenol to three earthworm species in artificial soil

    SciTech Connect

    Fitzgerald, D.; Lanno, R.P.; Farwell, A.; Dixon, D.G.

    1994-12-31

    Although methods for standardized toxicity tests with earthworms exist, many of the test parameters and conditions have not been validated in actual tests and with different species of worms. This study evaluated the toxicity of pentachlorophenol (PCP) to three species of earthworms, Lumbricus terrestris, Eisenia fetida, and Eudrilus eugeniae using various methods of data analysis and body residues. Tests were conducted in artificial soil for a period of 28 days or until an Acute Lethality Threshold (ALT) was reached. An intensive temporal sampling regime was applied to generate sufficient data for the accurate estimation of ALTs using both LC50/time and time-to-death/soil concentration methods of data analysis. L. terrestris was tested at 15 C, E. eugeniae at 24 C, and E. fetida at both temperatures. Total body residues of PCP were measured by GC following cryogenic separation of the lipid fraction of the worm. ALTs were significantly different between E. fetida and the two larger species of worms. No effect of temperature on the ALT for E. fetida was observed, although the time taken to reach the ALT increased at the lower temperature. The relationship of PCP residues at mortality will be discussed in terms of the effects of species, body size and temperature. Limitations of the artificial soil based upon growth curves of worms will also be examined.

  1. Selection of focal earthworm species as non-target soil organisms for environmental risk assessment of genetically modified plants.

    PubMed

    van Capelle, Christine; Schrader, Stefan; Arpaia, Salvatore

    2016-04-01

    By means of a literature survey, earthworm species of significant relevance for soil functions in different biogeographical regions of Europe (Atlantic, Boreal, Mediterranean) were identified. These focal earthworm species, defined here according to the EFSA Guidance Document on the environmental risk assessment (ERA) of genetically modified plants, are typical for arable soils under crop rotations with maize and/or potatoes within the three regions represented by Ireland, Sweden and Spain, respectively. Focal earthworm species were selected following a matrix of four steps: Identification of functional groups, categorization of non-target species, ranking species on ecological criteria, and final selection of focal species. They are recommended as appropriate non-target organisms to assess environmental risks of genetically modified (GM) crops; in this case maize and potatoes. In total, 44 literature sources on earthworms in arable cropping systems including maize or potato from Ireland, Sweden and Spain were collected, which present information on species diversity, individual density and specific relevance for soil functions. By means of condensed literature data, those species were identified which (i) play an important functional role in respective soil systems, (ii) are well adapted to the biogeographical regions, (iii) are expected to occur in high abundances under cultivation of maize or potato and (iv) fulfill the requirements for an ERA test system based on life-history traits. First, primary and secondary decomposers were identified as functional groups being exposed to the GM crops. In a second step, anecic and endogeic species were categorized as potential species. In step three, eight anecic and endogeic earthworm species belonging to the family Lumbricidae were ranked as relevant species: Aporrectodea caliginosa, Aporrectodea rosea, Aporrectodea longa, Allolobophora chlorotica, Lumbricus terrestris, Lumbricus friendi, Octodrilus complanatus and

  2. Hemagglutinins and bacterial agglutinins of earthworms.

    PubMed

    Stein, E A; Younai, S; Cooper, E L

    1987-01-01

    The biological roles of invertebrate agglutinins have been and remain an unresolved subject of controversy. Classical studies on agglutinins, beginning with the pioneer work of Noguchi (1903) on Limulus polyphemus and Homarus americanus have emphasized their hemagglutinating properties, an approach that has been criticized for its lack of biological relevance. While erythrocyte agglutination has proven useful for determining various properties of invertebrate agglutinins, it does not address the question of their natural function. More recently, invertebrate agglutinins have been investigated for their ability to interact with pathogenic agents such as bacteria (for review, see Pistole, 1982), yeast (Van der Knapp et al., 1982; Renwrantz and Stahmer, 1983) and parasitic protozoans (Ingram et al., 1984). In addition, the possible relationship of agglutinins to defense mechanisms of both vertebrates and invertebrates has been indicated by the observation that limulin, the major agglutinin of Limulus polyphemus, bears a number of similarities to vertebrate C-reactive proteins (Robey and Liu, 1981). In annelids, there have been no studies on bacterial agglutinins prior to our work with Lumbricus (Stein et al., 1985; Stein et al., submitted). Earthworms are particularly appropriate for studying bacterial agglutinins since their coelomic fluid contains constant low levels of bacteria and fungal spores, and their agglutinins are both naturally occurring and inducible. Although our initial studies on Lumbricus agglutinins were directed toward their hemagglutinating properties, our recent observations using bacteria have allowed us to reach the following conclusions: 1) Lumbricus coelomic fluid normally contains agglutinins against both erythrocytes and bacteria. After injecting worms with either erythrocytes or bacteria, agglutinin titers increase in coelomic fluid. This increase appears to be due to both an increase in numbers of agglutinins as well as levels of specific

  3. Unnecessary roughness? Testing the hypothesis that predators destined for molecular gut-content analysis must be hand-collected to avoid cross-contamination.

    PubMed

    Greenstone, Matthew H; Weber, Donald C; Coudron, Thomas C; Payton, Mark E

    2011-03-01

    Molecular gut-content analysis enables detection of arthropod predation with minimal disruption of ecosystem processes. Mass-collection methods, such as sweep-netting, vacuum sampling and foliage beating, could lead to regurgitation or rupturing of predators along with uneaten prey, thereby contaminating specimens and compromising resultant gut-content data. Proponents of this 'cross-contamination hypothesis' advocate hand-collection as the best way to avoid cross-contamination. However, hand-collection is inefficient when large samples are needed, as with most ecological research. We tested the cross-contamination hypothesis by setting out onto potato plants immature Coleomegilla maculata and Podisus maculiventris that had been fed larvae of either Leptinotarsa decemlineata or Leptinotarsa juncta, or unfed individuals of these predator species along with L. decemlineata larvae. The animals were then immediately re-collected, either by knocking them vigorously off the plants onto a beat cloth and capturing them en masse with an aspirator ('rough' treatment) or by hand-searching and collection with a brush ('best practice'). Collected predators were transferred in the field to individual vials of chilled ethanol and subsequently assayed by PCR for fragments of cytochrome oxidase I of L. decemlineata and L. juncta. Ten to 39 per cent of re-collected fed predators tested positive by PCR for DNA of both Leptinotarsa species, and 14-38% of re-collected unfed predators contained L. decemlineata DNA. Overall levels of cross-contamination in the rough (31%) and best-practice (11%) samples were statistically different and supported the cross-contamination hypothesis. A pilot study on eliminating external DNA contamination with bleach prior to DNA extraction and amplification gave promising results. PMID:21429135

  4. The role of sublethal effects in evaluating earthworm responses to soil contamination

    SciTech Connect

    Wilborn, D.; Bollman, M.; Linder, G.

    1994-12-31

    Frequently, standard test methods rely upon relatively straightforward, easily interpreted endpoints to evaluate biological effects, like growth inhibition, gross morbidity or death. In soil contamination evaluations, for example, earthworm toxicity tests are routinely completed in order to consider adverse biological effects associated with exposures to soil samples in the laboratory or field. Here, the toxicity endpoint measured in the standard test using Eisenia foetida is death; however, if chronic effects are more appropriate to the questions being asked within a risk assessment context, then alternative test endpoints must be developed and standardized. Prior evaluations have relied upon sublethal endpoints, most frequently behavioral and morphological observations, for evaluating chronic effects associated with contaminant exposures. The authors applied these behavioral and morphological endpoints in analyzing potential chronic effects in earthworms exposed to heavy metal-contaminated soils in both the laboratory and field. In using a relatively standard set of these sublethal endpoints the authors found that these endpoints could be used to evaluate chronic effects associated with soil exposures, but that selection of the specific end-points had to be adequately standardized and that observer bias had to be adequately characterized in order for these measures of chronic effects to be unequivocally applied within an ecological risk assessment.

  5. Postcopulatory inbreeding avoidance in guppies.

    PubMed

    Fitzpatrick, J L; Evans, J P

    2014-12-01

    In many species, the negative fitness effects of inbreeding have facilitated the evolution of a wide range of inbreeding avoidance mechanisms. Although avoidance mechanisms operating prior to mating are well documented, evidence for postcopulatory mechanisms of inbreeding avoidance remain scarce. Here, we examine the potential for paternity biases to favour unrelated males when their sperm compete for fertilizations though postcopulatory inbreeding avoidance mechanisms in the guppy, Poecilia reticulata. To test this possibility, we used a series of artificial inseminations to deliver an equal number of sperm from a related (either full sibling or half sibling) and unrelated male to a female while statistically controlling for differences in sperm quality between rival ejaculates. In this way, we were able to focus exclusively on postcopulatory mechanisms of inbreeding avoidance and account for differences in sperm competitiveness between rival males. Under these carefully controlled conditions, we report a significant bias in paternity towards unrelated males, although this effect was only apparent when the related male was a full sibling. We also show that sperm competition generally favours males with highly viable sperm and thus that some variance in sperm competitiveness can be attributed to difference in sperm quality. Our findings for postcopulatory inbreeding avoidance are consistent with prior work on guppies, revealing that sperm competition success declines linearly with the level of relatedness, but also that such effects are only apparent at relatedness levels of full siblings or higher. These findings reveal that postcopulatory processes alone can facilitate inbreeding avoidance. PMID:25387854

  6. Assessment of soil stabilization by chemical extraction and bioaccumulation using earthworm, Eisenia fetida

    NASA Astrophysics Data System (ADS)

    Lee, Byung-Tae; Abd Aziz, Azilah; Han, Heop Jo; Kim, Kyoung-Woong

    2014-05-01

    Soil stabilization does not remove heavy metals from contaminated soil, but lowers their exposures to ecosystem. Thus, it should be evaluated by measuring the fractions of heavy metals which are mobile and/or bioavailable in soils. The study compared several chemical extractions which intended to quantify the mobile or bioaccessible fractions with uptake and bioaccumulation by earthworm, Eisenia fetida. Soil samples were taken from the abandoned mine area contaminated with As, Cd, Cu, Pb and/or Zn. To stabilize heavy metals, the soils were amended with limestone and steel slag at 5% and 2% (w/w), respectively. All chemical extractions and earthworm tests were applied to both the contaminated and the stabilized soils with triplicates. The chemical extractions consisted of six single extractions which were 0.01M CaCl2 (unbufferred), EDTA or DTPA (chelating), TCLP (acidic), Mehlich 3 (mixture), and aqua regia (peudo-total). Sequential extractions were also applied to fractionate heavy metals in soils. In earthworm tests, worms were exposed to the soils for uptake of heavy metals. After 28 days of exposure to soils, worms were transferred to clean soils for elimination. During the tests, three worms were randomly collected at proper sampling events. Worms were rinsed with DI water and placed on moist filter paper for 48 h for depuration. Filter paper was renewed at 24 h to prevent coprophagy. The worms were killed with liquid nitrogen, dried in the oven, and digested with aqua regia for ICP-MS analysis. In addition to the bioaccumulation, several toxicity endpoints were observed such as burrowing time, mortality, cocoon production, and body weight changes. Toxicokinetics was applied to determine the uptake and elimination heavy metals by the earthworms. Bioaccumulation factor (BAF) was estimated using total metal concentrations and body burdens. Pearson correlation and simple linear regression were applied to evaluate the relationship between metal fractions by single

  7. Methylation of Mercury in Earthworms and the Effect of Mercury on the Associated Bacterial Communities

    PubMed Central

    Rieder, Stephan Raphael; Brunner, Ivano; Daniel, Otto; Liu, Bian; Frey, Beat

    2013-01-01

    Methylmercury compounds are very toxic for most organisms. Here, we investigated the potential of earthworms to methylate inorganic-Hg. We hypothesized that the anaerobic and nutrient-rich conditions in the digestive tracts of earthworm's promote the methylation of Hg through the action of their gut bacteria. Earthworms were either grown in sterile soils treated with an inorganic (HgCl2) or organic (CH3HgCl) Hg source, or were left untreated. After 30 days of incubation, the total-Hg and methyl-Hg concentrations in the soils, earthworms, and their casts were analyzed. The impact of Hg on the bacterial community compositions in earthworms was also studied. Tissue concentrations of methyl-Hg in earthworms grown in soils treated with inorganic-Hg were about six times higher than in earthworms grown in soils without Hg. Concentrations of methyl-Hg in the soils and earthworm casts remained at significantly lower levels suggesting that Hg was mainly methylated in the earthworms. Bacterial communities in earthworms were mostly affected by methyl-Hg treatment. Terminal-restriction fragments (T-RFs) affiliated to Firmicutes were sensitive to inorganic and methyl-Hg, whereas T-RFs related to Betaproteobacteria were tolerant to the Hg treatments. Sulphate-reducing bacteria were detected in earthworms but not in soils. PMID:23577209

  8. Does Uptake of Pharmaceuticals Vary Across Earthworm Species?

    PubMed

    Carter, Laura J; Ryan, Jim J; Boxall, Alistair B A

    2016-09-01

    This study compared the uptake and depuration of four commonly used pharmaceuticals (carbamazepine, diclofenac, fluoxetine and orlistat) in two earthworm species (Lumbricus terrestris and Eisenia fetida). L. terrestris are a larger species and often found in deep burrows whereas E. fetida prefer to reside near the soil surface. Species burrowing habits and sizes may alter uptake by earthworms. All four pharmaceuticals were taken up into both L. terrestris and E. fetida tissue after 21 days exposure to spiked soil. Bioconcentration factors (BCFs) ranged between 1.72 and 29.83 for L. terrestris and 1.14 and 63.03 for E. fetida. For carbamazepine and diclofenac, BCFs were similar whereas for fluoxetine and orlistat, BCFs in E. fetida were more than double those seen in L. terrestris. Results indicate that uptake into earthworms cannot be generalised between species and that the influence of species traits can vary depending on the nature of the study chemical. PMID:27443341

  9. Recombinant Protein Production of Earthworm Lumbrokinase for Potential Antithrombotic Application

    PubMed Central

    Wang, Kevin Yueju; Wang, Nan; Liu, Dehu

    2013-01-01

    Earthworms have been used as a traditional medicine in China, Japan, and other Far East countries for thousands of years. Oral administration of dry earthworm powder is considered as a potent and effective supplement for supporting healthy blood circulation. Lumbrokinases are a group of enzymes that were isolated and purified from different species of earthworms. These enzymes are recognized as fibrinolytic agents that can be used to treat various conditions associated with thrombosis. Many lumbrokinase (LK) genes have been cloned and characterized. Advances in genetic technology have provided the ability to produce recombinant LK and have made it feasible to purify a single lumbrokinase enzyme for potential antithrombotic application. In this review, we focus on expression systems that can be used for lumbrokinase production. In particular, the advantages of using a transgenic plant system to produce edible lumbrokinase are described. PMID:24416067

  10. Impact of Parthenium weeds on earthworms (Eudrilus eugeniae) during vermicomposting.

    PubMed

    Rajiv, P; Rajeshwari, Sivaraj; Rajendran, Venckatesh

    2014-11-01

    The aim of this work is to evaluate the effect of Parthenium-mediated compost on Eudrilus eugeniae during the process of vermicomposting. Nine different concentrations of Parthenium hysterophorus and cow dung mixtures were used to assess toxicity. The earthworms' growth, fecundity and antioxidant enzyme levels were analysed every 15 days. The antioxidant activities of enzymes [superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx)], considered as biomarkers, indicate the biochemical and oxidative stresses due to the toxin from Parthenium weeds. The earthworms' growth, biomass gain, cocoon production and antioxidant enzymes were in a low level in a high concentration of P. hysterophorus (without cow dung). The results clearly indicated that appropriate mixing of P. hysterophorus quantity is an essential factor for the survival of earthworms without causing any harm. PMID:24938809

  11. Phylogenomic analyses of a Mediterranean earthworm family (Annelida: Hormogastridae).

    PubMed

    Novo, Marta; Fernández, Rosa; Andrade, Sónia C S; Marchán, Daniel F; Cunha, Luis; Díaz Cosín, Darío J

    2016-01-01

    Earthworm taxonomy and evolutionary biology remain a challenge because of their scarce distinct morphological characters of taxonomic value, the morphological convergence by adaptation to the uniformity of the soil where they inhabit, and their high plasticity when challenged with stressful or new environmental conditions. Here we present a phylogenomic study of the family Hormogastridae, representing also the first piece of work of this type within earthworms. We included seven transcriptomes of the group representing the main lineages as previously-described, analysed in a final matrix that includes twelve earthworms and eleven outgroups. While there is a high degree of gene conflict in the generated trees that obscure some of the internal relationships, the origin of the family is well resolved: the hormogastrid Hemigastrodrilus appears as the most ancestral group, followed by the ailoscolecid Ailoscolex, therefore rejecting the validity of the family Ailoscolecidae. Our results place the origin of hormogastrids in Southern France, as previously hypothesised. PMID:26522608

  12. Avoiding the Flu

    MedlinePlus

    ... of this page please turn Javascript on. Feature: Flu Avoiding the Flu Past Issues / Fall 2009 Table of Contents Children ... help avoid getting and passing on the flu. Influenza (Seasonal) The flu is a contagious respiratory illness ...

  13. Heavy metal concentrations in soil and earthworms in a floodplain grassland.

    PubMed

    van Vliet, P C J; van der Zee, S E A T M; Ma, W C

    2005-12-01

    We determined accumulated heavy metal concentrations (Cd, Pb, Cu, Zn) of earthworms in moderately contaminated floodplain soils. Both soil and mature earthworms were sampled before and after flooding and earthworm species were identified to understand species specific differences in bioconcentration. Accumulated metal concentrations in floodplain earthworms differed before and after flooding. Differences in uptake and elimination mechanisms, in food choice and living habitat of the different earthworm species and changes in speciation of the heavy metals are possible causes for this observation. Regression equations taken from literature, that relate metal accumulation by earthworms in floodplains as a function of metal concentration in soil, performed well when all species specific data were combined in an average accumulation, but did not address differences in accumulation between earthworm species. PMID:15951081

  14. Earthworm bioturbation influences the phytoavailability of metals released by particles in cultivated soils.

    PubMed

    Leveque, Thibaut; Capowiez, Yvan; Schreck, Eva; Xiong, Tiantian; Foucault, Yann; Dumat, Camille

    2014-08-01

    The influence of earthworm activity on soil-to-plant metal transfer was studied by carrying out six weeks mesocosms experiments with or without lettuce and/or earthworms in soil with a gradient of metal concentrations due to particles fallouts. Soil characteristics, metal concentrations in lettuce and earthworms were measured and soil porosity in the mesocosms was determined. Earthworms increased the soil pH, macroporosity and soil organic matter content due to the burying of wheat straw provided as food. Earthworm activities increased the metals concentrations in lettuce leaves. Pb and Cd concentrations in lettuce leaves can increase up to 46% with earthworm activities … These results and the low correlation between estimated by CaCl2 and EDTA and measured pollutant phytoavailability suggest that earthworm bioturbation was the main cause of the increase. Bioturbation could affect the proximity of pollutants to the roots and soil organic matter. PMID:24858803

  15. Earthworms facilitate the stabilization of pelletized dewatered sludge through shaping microbial biomass and activity and community.

    PubMed

    Fu, Xiaoyong; Cui, Guangyu; Huang, Kui; Chen, Xuemin; Li, Fusheng; Zhang, Xiaoyu; Li, Fei

    2016-03-01

    In this study, the effect of earthworms on microbial features during vermicomposting of pelletized dewatered sludge (PDS) was investigated through comparing two degradation systems with and without earthworm E isenia fetida involvement. After 60 days of experimentation, a relatively stable product with low organic matter and high nitrate and phosphorous was harvested when the earthworms were involved. During the process, earthworms could enhance microbial activity and biomass at the initial stage and thus accelerating the rapid decomposition of PDS. The end products of vermicomposting allowed the lower values of bacterial and eukaryotic densities comparison with those of no earthworm addition. In addition, the presence of earthworms modified the bacterial and fungal diversity, making the disappearances of some pathogens and specific decomposing bacteria of recalcitrant substrates in the vermicomposting process. This study evidences that earthworms can facilitate the stabilization of PDS through modifying microbial activity and number and community during vermicomposting. PMID:26514568

  16. Interactions between the nematode parasite of pigs, Ascaris suum, and the earthworm Aporrectodea longa.

    PubMed

    Kraglund, H O; Grønvold, J; Roepstorff, A; Rawat, H

    1998-01-01

    Pig faeces in which Ascaris suum eggs had been embryonating for 57 days were placed in buckets of soil containing either 30 or no earth-worms (Aporrectodea longa). When present, earthworms consumed the faeces and transported the eggs down into the soil, without inflicting any visible damage on the eggs. In later experiments 10 earthworms from the above experiment were fed to each of ten pigs, and another 40 earthworms were dissected. None of the 10 pigs became infected with A. suum through consumption of earthworms, and none of the dissected earthworms were found to contain A. suum larvae. This experiment indicates that A. longa did not act as a paratenic host for A. suum but shows that earthworms are very efficient in transporting A. suum eggs from faeces deposited on the soil surface into the soil. PMID:9926459

  17. Accumulation of chlorinated benzenes in earthworms

    SciTech Connect

    Beyer, W.N.

    1996-12-31

    Chlorinated benzenes are widespread in the environment. Hexachlorobenzene, pentachlorobenzene and all isomers of dichlorobenzenes, trichlorobenzenes, and tetrachlorobenzenes, have been detected in fish, water, and sediments from the Great Lakes. They probably entered the water as leachates from chemical waste dumps and as effluents from manufacturing. Hexachlorobenzene and pentachlorobenzene are commonly present in Herring gull (Larus argentatus) eggs from the Great Lakes, and some of the isomers of trichlorobenzene and tetrachlorobenzene are occasionally detected at low concentrations. Hexachlorobenzene, which was formerly used as a fungicide, has been the most thoroughly studied chlorinated benzene, and has been detected in many species. Its use as a fungicide in the United States was canceled in 1984. Since about 1975 hexachlorobenzene has been formed mainly in the production of chlorinated solvents. It is highly persistent in the environment and some species are poisoned by hexachlorobenzene at very low chronic dietary exposures. As little as 1 ppm in the diet of mink (Mustela vison) reduced the birth weights of young, and 5 ppm in the diet of Japanese quail (Coturnix coturnix japonica) caused slight liver damage. This paper describes a long-term (26 wk) experiment relating the concentrations of chlorinated benzenes in earthworms to length of exposure and three 8 wk experiments relating concentration to the concentration in soil the soil organic matter content, and the degree of chlorination. 20 refs., 3 figs., 1 tab.

  18. Metal/metalloid (As, Cd and Zn) bioaccumulation in the earthworm Eisenia andrei under different scenarios of climate change.

    PubMed

    González-Alcaraz, M Nazaret; van Gestel, Cornelis A M

    2016-08-01

    This study aimed at assessing the effects of global warming (increasing air temperature and decreasing soil moisture content) on the bioaccumulation kinetics of As, Cd and Zn in the earthworm Eisenia andrei in two polluted soils (mine tailing and watercourse soil). Earthworms were exposed for up to 21 d under four climate conditions: 20 °C + 50% soil water holding capacity (WHC) (standard conditions), 20 °C + 30% WHC, 25 °C + 50% WHC and 25 °C + 30% WHC. Porewater metal/metalloid availability did not change in the mine tailing soil after the incubation period under the different climate conditions tested. However, in the watercourse soil, porewater Cd concentrations decreased from ∼63 to ∼32-41 μg L(-1) after 21 d and Zn concentrations from ∼3761 to ∼1613-2170 μg L(-1), especially at 20 °C and 50% WHC. In both soils, As and Zn showed similar bioaccumulation patterns in the earthworms, without major differences among climate conditions. Earthworm concentrations peaked after 1-3 d of exposure (in μg g(-1) dry weight: As∼32.5-108, Zn∼704-1172) and then remained constant (typical pattern of essential elements even for As). For Cd the bioaccumulation pattern changed when changing the climate conditions. Under standard conditions, earthworm Cd concentrations increased to ∼12.6-18.5 μg g(-1) dry weight without reaching equilibrium (typical pattern of non-essential elements). However when increasing temperature and/or decreasing soil moisture content the bioaccumulation pattern changed towards that more typical of essential elements due to increased Cd elimination rates (from ∼0.11 to ∼0.24-1.27 d(-1) in the mine tailing soil, from ∼0.07 to ∼0.11-0.35 d(-1) in the watercourse soil) and faster achievement of a steady state. This study shows that metal/metalloid bioaccumulation pattern in earthworms may change dependent on climate conditions. PMID:27182979

  19. Comparative toxicity and biochemical responses of certain pesticides to the mature earthworm Aporrectodea caliginosa under laboratory conditions.

    PubMed

    Mosleh, Yahia Y; Ismail, Saad M M; Ahmed, Mohamed T; Ahmed, Yousery M

    2003-10-01

    This study was conducted to investigate the toxicity of aldicarb, cypermethrin, profenofos, chlorfluazuron, atrazine, and metalaxyl toward mature Aporrectodea caliginosa earthworms. The effects of the LC(25) values of these pesticides on the growth rate in relation to glucose, soluble protein, and activities of glutamic-oxaloacetic transaminase (GOT), glutamic-pyruvic transaminase (GPT), acid phosphatase (AcP), and alkaline phosphatase (AIP) were also studied. The results showed that aldicarb was the most toxic of the tested pesticides, followed in order by cypermethrin, profenofos, chlorfluazuron, atrazine, and metalaxyl. A reduction in growth rate was observed in all pesticide-treated worms, which was accompanied by a decrease in soluble protein and an increase in transaminases and phosphatases. Relationships between growth rate, protein content, transaminases, and phosphatases provided strong evidence for the involvement of pesticidal contamination in the biochemical changes in earthworms, which can be used as a bioindicator of soil contamination by pesticides. PMID:14502587

  20. Regional extent of an ecosystem engineer: earthworm invasion in northern hardwood forests.

    PubMed

    Holdsworth, Andrew R; Frelich, Lee E; Reich, Peter B

    2007-09-01

    The invasion of exotic earthworms into northern temperate and boreal forests previously devoid of earthworms is an important driver of ecosystem change. Earthworm invasion can cause significant changes in soil structure and communities, nutrient cycles, and the diversity and abundance of herbaceous plants. However, the regional extent and patterns of this invasion are poorly known. We conducted a regional survey in the Chippewa and Chequamegon National Forests, in Minnesota and Wisconsin, U.S.A., respectively, to measure the extent and patterns of earthworm invasion and their relationship to potential earthworm introduction sites. We sampled earthworms, soils, and vegetation in 20 mature, sugar maple-dominated forest stands in each national forest and analyzed the relationship between the presence of five earthworm taxonomic groups, habitat variables, and distance to the nearest potential introduction site. Earthworm invasion was extensive but incomplete in the two national forests. Four of the six earthworm taxonomic groups occurred in 55-95% of transects; however 20% of all transects were invaded by only one taxonomic group that has relatively minor ecological effects. Earthworm taxonomic groups exhibited a similar sequence of invasion found in other studies: Dendrobaena > Aporrectodea = Lumbricus juveniles > L. rubellus > L. terrestris. Distance to the nearest road was the best predictor of earthworm invasion in Wisconsin while distance to the nearest cabin was the best predictor in Minnesota. These data allow us to make preliminary assessments of landscape patterns of earthworm invasion. As an example, we estimate that 82% of upland mesic hardwood stands in the Wisconsin region are likely invaded by most taxonomic groups while only 3% are unlikely to be invaded at present. Distance to roads and cabins provides a coarse-scale predictor of earthworm invasion to focus stand-level assessments that will help forest managers better understand current and potential

  1. Treatment Planning Constraints to Avoid Xerostomia in Head-and-Neck Radiotherapy: An Independent Test of QUANTEC Criteria Using a Prospectively Collected Dataset

    SciTech Connect

    Moiseenko, Vitali; Wu, Jonn; Hovan, Allan; Saleh, Ziad; Apte, Aditya; Deasy, Joseph O.; Harrow, Stephen; Rabuka, Carman; Muggli, Adam; Thompson, Anna

    2012-03-01

    Purpose: The severe reduction of salivary function (xerostomia) is a common complication after radiation therapy for head-and-neck cancer. Consequently, guidelines to ensure adequate function based on parotid gland tolerance dose-volume parameters have been suggested by the QUANTEC group and by Ortholan et al. We perform a validation test of these guidelines against a prospectively collected dataset and compared with a previously published dataset. Methods and Materials: Whole-mouth stimulated salivary flow data from 66 head-and-neck cancer patients treated with radiotherapy at the British Columbia Cancer Agency (BCCA) were measured, and treatment planning data were abstracted. Flow measurements were collected from 50 patients at 3 months, and 60 patients at 12-month follow-up. Previously published data from a second institution, Washington University in St. Louis (WUSTL), were used for comparison. A logistic model was used to describe the incidence of Grade 4 xerostomia as a function of the mean dose of the spared parotid gland. The rate of correctly predicting the lack of xerostomia (negative predictive value [NPV]) was computed for both the QUANTEC constraints and Ortholan et al. recommendation to constrain the total volume of both glands receiving more than 40 Gy to less than 33%. Results: Both datasets showed a rate of xerostomia of less than 20% when the mean dose to the least-irradiated parotid gland is kept to less than 20 Gy. Logistic model parameters for the incidence of xerostomia at 12 months after therapy, based on the least-irradiated gland, were D{sub 50} = 32.4 Gy and and {gamma} = 0.97. NPVs for QUANTEC guideline were 94% (BCCA data), and 90% (WUSTL data). For Ortholan et al. guideline NPVs were 85% (BCCA) and 86% (WUSTL). Conclusion: These data confirm that the QUANTEC guideline effectively avoids xerostomia, and this is somewhat more effective than constraints on the volume receiving more than 40 Gy.

  2. Taxonomic and functional diversity of the culturable microbiomes of epigeic earthworms and their prospects in agriculture.

    PubMed

    Singh, Arjun; Tiwari, Rameshwar; Sharma, Anamika; Adak, Anurup; Singh, Surender; Prasanna, Radha; Saxena, Anil K; Nain, Lata; Singh, Ran Vir

    2016-09-01

    Eisenia foetida and Perionyx excavatus are potent vermicomposting earthworms having immense importance in organic matter recycling under tropical conditions, particularly in India. Comparative assessment of the cultivable gut microbiome of these two epigeic earthworms after growth on lignocellulosic biomass, revealed populations of 3.2-8.3 × 10(9) CFU. Diversity analyses using 16S rDNA sequences revealed that the major dominating classes were Firmicutes (50-60%), followed by Actinobacteria (26.7-33%), and Alphaproteobacteria (5.6-6.7%). Despite exhibiting similar diversity indices and species richness, Betaproteobacteria (6.7%) and Gammaproteobacteria (11.1%) were solely present in E. foetida and P. excavatus, respectively. A set of 33 distinct morphotypes, including 18 from E. foetida and 15 from P. excavatus were selected. Carbohydrate utilization profiles generated using Hi-Carbo™ kits revealed that the isolates from the gut of P. excavatus - Arthrobacter pascens IARI-L13 and Bacillus subtilis IARIC were able to utilize 54 and 51.4% of the carbohydrates tested. Sorbose was not utilized, while unusual carbohydrates - adonitol and methyl-d-mannoside were utilized only by members from the gut of P. excavatus, while melizitose was utilized by those uniquely by E. foetida microbiome. Functional characterization revealed that β-glucosidase activity was most prevalent in the culturable microbial community. Alkaline and acid phosphatase activity was more widespread in the E. foetida gut microbiome. All the culturable gut bacterial isolates produced ammonia, but IAA was detected only in five cultures. The unique functional attributes of the two culturable microbiomes, grown on a similar diet, reveals the significance of proper selection of earthworm substrate combinations for effective vermicomposting. PMID:27133232

  3. Screening of actinomycetes from earthworm castings for their antimicrobial activity and industrial enzymes.

    PubMed

    Kumar, Vijay; Bharti, Alpana; Negi, Yogesh Kumar; Gusain, Omprakash; Pandey, Piyush; Bisht, Gajraj Singh

    2012-01-01

    Actinomycetes from earthworm castings were isolated and screened for their antimicrobial activity and industrial enzymes. A total of 48 isolates were obtained from 12 samples of earthworm castings. Highest numbers of isolates were recovered from forest site (58.33 %) as compared to grassland (25%) and agricultural land (16.66%). The growth patterns, mycelial coloration of abundance actinomycetes were documented. The dominant genera Identified by cultural, morphological and physiological characteristics were Streptomyces (60.41%) followed by Streptosporangium (10.41%),Saccharopolyspora (6.25%) and Nocardia (6.25%). Besides these, other genera like Micromonospora, Actinomadura, Microbispora, Planobispora and Nocardiopsis were also recovered but in low frequency. Among the 48 isolates, 52.08% were found active against one or more test organisms. Out of 25 active isolates 16% showed activity against bacterial, human fungal as well as phytopathogens. Among 48 isolates 38, 32, 21, 20, 16 and 14 produced enzyme amylase, caseinase, cellulase, gelatinase, xylanase and lipase respectively while 10 isolates produced all the enzymes. More interestingly 2, 3, and 1 isolates produced amylase, xylanase and lipase at 45°C respectively. In the view of its antimicrobial activity as well as enzyme production capability the genus Streptomyces was dominant. The isolate EWC 7(2) was most promising on the basis of its interesting antimicrobial activity and was identified as Streptomyces rochei. The results of these findings have increased the scope of finding industrially important actinomycetes from earthworm castings and these organisms could be promising sources for industrially important molecules or enzymes. PMID:24031819

  4. Hybridization relics complicate barcode-based identification of species in earthworms.

    PubMed

    Dupont, L; Porco, D; Symondson, W O C; Roy, V

    2016-07-01

    Introgressive hybridization results in mito-nuclear discordance which could obscure the delimitation of closely related taxa. Although such events are increasingly reported, they have been poorly studied in earthworms. Here, we propose a method for investigating the degree of introgressive hybridization between three taxa of the Allolobophora chlorotica aggregate within two field populations (N = 67 and N = 105) using a reference data set including published DNA barcoding and microsatellite data of all known A. chlorotica lineages (N = 85). For this, we used both molecular phylogenetic and population genetic approaches. The test of correspondence between mitochondrial cytochrome c oxidase I (COI) lineages and clusters of nuclear microsatellite genotypes allowed individuals to be sorted in three categories (matching, admixed and nonmatching) and additional markers (mitochondrial NADH dehydrogenase subunit 1, nuclear Histone 3 and Internal transcribed Spacer Region 2) were used for phylogenetic reconstructions in order to check assignments. Although 15 admixed individuals were observed, no early-generation hybrids were detected within the two populations. Interestingly, 14 nonmatching individuals (i.e. with a mtDNA haplotype that did not correspond to their nuclear cluster) were detected, a pattern that would result after multiple generations of unidirectional hybridization of female from one taxon to male of the other taxon. Because earthworms are simultaneous hermaphrodites, these events of unidirectional hybridization suggest sterility of the male function in several crosses and highlight that some individuals can be misidentified if reliance is placed on COI barcodes alone. These findings could improve the use of these barcodes in earthworms for species delineation. PMID:26929276

  5. Screening of actinomycetes from earthworm castings for their antimicrobial activity and industrial enzymes

    PubMed Central

    Kumar, Vijay; Bharti, Alpana; Negi, Yogesh Kumar; Gusain, Omprakash; Pandey, Piyush; Bisht, Gajraj Singh

    2012-01-01

    Actinomycetes from earthworm castings were isolated and screened for their antimicrobial activity and industrial enzymes. A total of 48 isolates were obtained from 12 samples of earthworm castings. Highest numbers of isolates were recovered from forest site (58.33 %) as compared to grassland (25%) and agricultural land (16.66%). The growth patterns, mycelial coloration of abundance actinomycetes were documented. The dominant genera Identified by cultural, morphological and physiological characteristics were Streptomyces (60.41%) followed by Streptosporangium (10.41%),Saccharopolyspora (6.25%) and Nocardia (6.25%). Besides these, other genera like Micromonospora, Actinomadura, Microbispora, Planobispora and Nocardiopsis were also recovered but in low frequency. Among the 48 isolates, 52.08% were found active against one or more test organisms. Out of 25 active isolates 16% showed activity against bacterial, human fungal as well as phytopathogens. Among 48 isolates 38, 32, 21, 20, 16 and 14 produced enzyme amylase, caseinase, cellulase, gelatinase, xylanase and lipase respectively while 10 isolates produced all the enzymes. More interestingly 2, 3, and 1 isolates produced amylase, xylanase and lipase at 45°C respectively. In the view of its antimicrobial activity as well as enzyme production capability the genus Streptomyces was dominant. The isolate EWC 7(2) was most promising on the basis of its interesting antimicrobial activity and was identified as Streptomyces rochei. The results of these findings have increased the scope of finding industrially important actinomycetes from earthworm castings and these organisms could be promising sources for industrially important molecules or enzymes. PMID:24031819

  6. Solid phase microextraction of organic pollutants from natural and artificial soils and comparison with bioaccumulation in earthworms.

    PubMed

    Bielská, Lucie; Šmídová, Klára; Hofman, Jakub

    2014-02-01

    The presented study investigates the use of passive sampling, i.e. solid phase microextraction with polydimethylsiloxane fibers (PDMS-SPME), to assess the bioavailability of fiver neutral organic chemicals (phenanthrene, pyrene, lindane, p,p'-DDT, and PCB 153) spiked to natural and artificial soils after different aging times. Contaminant bioavailability was assessed by comparing PDMS concentrations with results from a 10 day bioaccumulation test with earthworms (Eisenia fetida). The hypotheses tested were (i) organic carbon (OC) normalization, which is commonly used to account for sorption and bioavailability of hydrophobic organic chemicals in soil risk assessment, has limitations due to differences in sorptive properties of OC and aging processes (i.e. sequestration and biodegradation) and (ii) PDMS-SPME provides a more reliable measure of soil contaminant bioavailability than OC normalized soil concentrations. The above stated hypotheses were confirmed since the results showed that: (i) the PDMS/soil organic carbon partition ratio (R) accounting for the role that OC plays in partitioning significantly differed between soils and aging times and (ii) the correlation with earthworm concentrations was better using porewater concentrations derived from PDMS concentrations than when organic normalized soil concentrations were used. Capsule: Sorption of organic compounds measured by SPME method and their bioavailability to earthworms cannot be reliably predicted using OC content. PMID:24433790

  7. A multi-biomarker risk assessment of the impact of brominated flame retardant-decabromodiphenyl ether (BDE209) on the antioxidant system of earthworm Eisenia fetida.

    PubMed

    Zhang, Wei; Liu, Kou; Chen, Lin; Chen, Lei; Lin, Kuangfei; Fu, Rongbing

    2014-07-01

    Decabromodiphenyl ether (BDE209) is the major contaminant at e-waste recycling sites (EWRSs), and its potential toxicological effects on terrestrial organisms have received extensive attention. However, the impacts of BDE209 on the antioxidant defense system in terrestrial organisms remain vague. Therefore, indoor incubation tests were performed systematically on control and contaminated soil samples to determine the effects of BDE209 on the antioxidant system of earthworm Eisenia fetida. The results showed that compared to the controls, superoxide dismutase (SOD) activities in all treated groups were elevated significantly after 21 and 28 days exposure; catalase (CAT) activities were much higher in all tests during the entire exposure period; peroxidase (POD) and glutathione-s-transferase (GST) activities generally decreased and indicated contrary response trend; the total antioxidant capacity (T-AOC) after exposure to low level of BDE209 (1 mg kg(-1)) was induced, whereas at 10 and 100 mg kg(-1) concentrations it showed suppression status; electron paramagnetic resonance (EPR) spectra suggested that hydroxyl radicals (OH) in earthworms were significantly induced by BDE209; the changes in malondialdehyde (MDA) contents suggested that reactive oxygen species (ROS) might lead to cellular lipid peroxidation in earthworms. The results of these observations suggested that severe oxidative stress occurred in E. fetida, and it may play an important role in inducing the BDE209 toxicity to earthworms. PMID:25016100

  8. Behavioral avoidance and self-reported fainting symptoms in blood/injury fearful individuals: an experimental test of disgust domain specificity.

    PubMed

    Olatunji, Bunmi O; Connolly, Kevin M; David, Bieke

    2008-06-01

    This study examined the specificity of disgust in predicting avoidance in blood/injury (BI) phobia. Participants high (n=38) and low (n=46) in BI fear completed measures of disgust across multiple domains and severity of BI-related fear. They then completed three randomly presented behavioral avoidance tasks (BATs) that consisted of exposure to a 15'' severed deer leg (BI task), a live spider (spider task), and a 'contaminated' cookie (cookie task). Fainting symptoms associated with each BAT were recorded as well. When controlling for gender and BI fear group membership, mutilation disgust contributed unique variance to avoidance on the BI task and animal disgust contributed unique variance to avoidance on the spider task. None of the disgust domains contributed unique variance to avoidance on the cookie task. For the high BI fear group, self-reported fainting symptoms were more pronounced during the BI and spider BAT than during the cookie BAT. Although mutilation disgust was significantly associated with self-reported fainting symptoms on the BI task among the high BI fear group, this relationship became nonsignificant when controlling for BI-related fear severity. Implications of the domain specificity of disgust and its relevance for understanding fainting responses in BI phobia are discussed. PMID:17920808

  9. Acute Toxicity and Genotoxicity of Carbendazim, Main Impurities and Metabolite to Earthworms (Eisenia foetida).

    PubMed

    Huan, Zhibo; Luo, Jinhui; Xu, Zhi; Xie, Defang

    2016-01-01

    The acute toxicity and genotoxicity of carbendazim, two impurities (3-amino-2-hydroxyphenazine and 2,3-diaminophenazine) and one metabolite (2-aminobenzimidazole) to Eisenia foetida were assessed using artificial soil test and comet assay respectively. Acute toxicity results showed carbendazim was moderately toxic to the earthworms with 14 day-LC50 of 8.6 mg/kg dry soil while 3-amino-2-hydroxyphenazine, 2,3-diaminophenazine, and 2-aminobenzimidazole were of low toxicity with 14 day-LC50 values of 19.0, 14.9, and 27.7 mg/kg dry soil respectively (nominal concentration). The olive tail moment and percentage of DNA in the tail were used as genotoxicity indices, and carbendazim could significantly induce DNA damage to the earthworm coelomocytes with obviously positive dose- and duration-response relationships while the other three substances showed similar (p = 0.05) genotoxicity results to the negative controls in all of the tests. PMID:26370277

  10. Heavy metal concentrations in earthworms from soil amended with sewage sludge

    USGS Publications Warehouse

    Beyer, W.N.; Chaney, R.L.; Mulhern, B.M.

    1982-01-01

    Metal concentrations in soil may be elevated considerably when metal-laden sewage sludge is spread on land. Metals in earthworms (Lumbricidae) from agricultural fields amended with sewage sludge and from experimental plots were examined to determine if earthworms are important in transferring metals in soil to wildlife. Earthworms from four sites amended with sludge contained significantly (P . < 0.05) more Cd (12 times), Cu (2.4 times), Zn (2.0 times), and Pb (1.2 times) than did earthworms from control sites, but the concentrations detected varied greatly and depended on the particular sludge application. Generally, Cd and Zn were concentrated by earthworms relative to soil, and Cu, Pb, and Ni were not concentrated. Concentrations of Cd, Zn, Cu, and Pb in earthworms were correlated (P < 0.05) with those in soil. The ratio of the concentration of metals in earthworms to the concentration of metals in soil tended to be lower in contaminated soil than in clean soil. Concentrations of Cd as high as 100 ppm (dry wt) were detected in earthworms from soil containing only 2 ppm Cd. These concentrations are considered hazardous to wildlife that eat worms. Liming soil decreased Cd concentrations in earthworms slightly (P < 0.05) but had no discernible effect on concentrations of the other metals studied. High Zn concentrations in soil substantially reduced Cd concentrations in earthworms.

  11. Soil Penetration by Earthworms and Plant Roots—Mechanical Energetics of Bioturbation of Compacted Soils

    PubMed Central

    2015-01-01

    We quantify mechanical processes common to soil penetration by earthworms and growing plant roots, including the energetic requirements for soil plastic displacement. The basic mechanical model considers cavity expansion into a plastic wet soil involving wedging by root tips or earthworms via cone-like penetration followed by cavity expansion due to pressurized earthworm hydroskeleton or root radial growth. The mechanical stresses and resulting soil strains determine the mechanical energy required for bioturbation under different soil hydro-mechanical conditions for a realistic range of root/earthworm geometries. Modeling results suggest that higher soil water content and reduced clay content reduce the strain energy required for soil penetration. The critical earthworm or root pressure increases with increased diameter of root or earthworm, however, results are insensitive to the cone apex (shape of the tip). The invested mechanical energy per unit length increase with increasing earthworm and plant root diameters, whereas mechanical energy per unit of displaced soil volume decreases with larger diameters. The study provides a quantitative framework for estimating energy requirements for soil penetration work done by earthworms and plant roots, and delineates intrinsic and external mechanical limits for bioturbation processes. Estimated energy requirements for earthworm biopore networks are linked to consumption of soil organic matter and suggest that earthworm populations are likely to consume a significant fraction of ecosystem net primary production to sustain their subterranean activities. PMID:26087130

  12. Heavy metal concentrations in earthworms from soil amended with sewage slude

    SciTech Connect

    Beyer, W.N.; Chaney, R.L.; Mulhern, B.M.

    1982-07-01

    Metal concentrations in soil may be elevated considerably when metal-laden sewage sludge is spread on land. Metals in earthworms (Lumbricidae) from agicultural fields amended with sewage sludge and from experimental plots were examined to determine if earthworms are important in transferring metals in soil to wildlife. Earthworms from four sites amended with sludge contained significantly (P<0.05) more Cd (12 times), Cu (2.4 times), Zn (2.0 times), and Pb (1.2 times) than did earthworms from control sites, but the concentrations detected varied greatly and depended on the particular sludge application. Generally, Cd and Zn were concentrated by earthworms relative to soil, and Cu, Pb, and Ni were not concentrated. Concentrations of Cd, Zn, Cu, and Pb in earthworms were correlated (P<0.05) with those in soil. The ratio of the concentration of metals in earthworms to the concentration of metals in soil tended to be lower in contaminated soil than in clean soil. Concentrations of Cd as high as 100 ppm (dry wt) were detected in earthworms from soil containing only 2 ppm Cd. These concentrations are considered hazardous to wildlife that eat worms. Liming soil decreased Cd concentrations in earthworms slightly (P<0.05) but had no discernible effect on concentrations of the other metals studied. High Zn concentrations in soil substantially reduced Cd concentrations in earthworms.

  13. Soil Penetration by Earthworms and Plant Roots--Mechanical Energetics of Bioturbation of Compacted Soils.

    PubMed

    Ruiz, Siul; Or, Dani; Schymanski, Stanislaus J

    2015-01-01

    We quantify mechanical processes common to soil penetration by earthworms and growing plant roots, including the energetic requirements for soil plastic displacement. The basic mechanical model considers cavity expansion into a plastic wet soil involving wedging by root tips or earthworms via cone-like penetration followed by cavity expansion due to pressurized earthworm hydroskeleton or root radial growth. The mechanical stresses and resulting soil strains determine the mechanical energy required for bioturbation under different soil hydro-mechanical conditions for a realistic range of root/earthworm geometries. Modeling results suggest that higher soil water content and reduced clay content reduce the strain energy required for soil penetration. The critical earthworm or root pressure increases with increased diameter of root or earthworm, however, results are insensitive to the cone apex (shape of the tip). The invested mechanical energy per unit length increase with increasing earthworm and plant root diameters, whereas mechanical energy per unit of displaced soil volume decreases with larger diameters. The study provides a quantitative framework for estimating energy requirements for soil penetration work done by earthworms and plant roots, and delineates intrinsic and external mechanical limits for bioturbation processes. Estimated energy requirements for earthworm biopore networks are linked to consumption of soil organic matter and suggest that earthworm populations are likely to consume a significant fraction of ecosystem net primary production to sustain their subterranean activities. PMID:26087130

  14. The earthworm Aporrectodea caliginosa stimulates abundance and activity of phenoxyalkanoic acid herbicide degraders

    PubMed Central

    Liu, Ya-Jun; Zaprasis, Adrienne; Liu, Shuang-Jiang; Drake, Harold L; Horn, Marcus A

    2011-01-01

    2-Methyl-4-chlorophenoxyacetic acid (MCPA) is a widely used phenoxyalkanoic acid (PAA) herbicide. Earthworms represent the dominant macrofauna and enhance microbial activities in many soils. Thus, the effect of the model earthworm Aporrectodea caliginosa (Oligochaeta, Lumbricidae) on microbial MCPA degradation was assessed in soil columns with agricultural soil. MCPA degradation was quicker in soil with earthworms than without earthworms. Quantitative PCR was inhibition-corrected per nucleic acid extract and indicated that copy numbers of tfdA-like and cadA genes (both encoding oxygenases initiating aerobic PAA degradation) in soil with earthworms were up to three and four times higher than without earthworms, respectively. tfdA-like and 16S rRNA gene transcript copy numbers in soil with earthworms were two and six times higher than without earthworms, respectively. Most probable numbers (MPNs) of MCPA degraders approximated 4 × 105 gdw−1 in soil before incubation and in soil treated without earthworms, whereas MPNs of earthworm-treated soils were approximately 150 × higher. The aerobic capacity of soil to degrade MCPA was higher in earthworm-treated soils than in earthworm-untreated soils. Burrow walls and 0–5 cm depth bulk soil displayed higher capacities to degrade MCPA than did soil from 5–10 cm depth bulk soil, expression of tfdA-like genes in burrow walls was five times higher than in bulk soil and MCPA degraders were abundant in burrow walls (MPNs of 5 × 107 gdw−1). The collective data indicate that earthworms stimulate abundance and activity of MCPA degraders endogenous to soil by their burrowing activities and might thus be advantageous for enhancing PAA degradation in soil. PMID:20740027

  15. Automatic Collision Avoidance Technology (ACAT)

    NASA Technical Reports Server (NTRS)

    Swihart, Donald E.; Skoog, Mark A.

    2007-01-01

    This document represents two views of the Automatic Collision Avoidance Technology (ACAT). One viewgraph presentation reviews the development and system design of Automatic Collision Avoidance Technology (ACAT). Two types of ACAT exist: Automatic Ground Collision Avoidance (AGCAS) and Automatic Air Collision Avoidance (AACAS). The AGCAS Uses Digital Terrain Elevation Data (DTED) for mapping functions, and uses Navigation data to place aircraft on map. It then scans DTED in front of and around aircraft and uses future aircraft trajectory (5g) to provide automatic flyup maneuver when required. The AACAS uses data link to determine position and closing rate. It contains several canned maneuvers to avoid collision. Automatic maneuvers can occur at last instant and both aircraft maneuver when using data link. The system can use sensor in place of data link. The second viewgraph presentation reviews the development of a flight test and an evaluation of the test. A review of the operation and comparison of the AGCAS and a pilot's performance are given. The same review is given for the AACAS is given.

  16. Earthworm Biomass Measurement: A Science Activity for Middle School.

    ERIC Educational Resources Information Center

    Haskett, Jonathan; Levine, Elissa; Carey, Pauline B.; Niepold III, Frank

    2000-01-01

    Describes an activity on biomass measurement which, in this case, is the weight of a group of living things in a given area. The earthworm activity gives students a greater understanding of ecology, practical math applications, and the scientific method. (ASK)

  17. The Earthworms (Oligochaeta: Lumbricidae)of Wyoming, USA, Revisited.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This survey of the earthworms from 22 of the 23 counties of Wyoming recorded 13 species of terrestrial Oligochaeta, all members of the family Lumbricidae. One of these species, Aporrectodea limicola, is reported for the first time from the state. Current nomenclature is applied to historical records...

  18. Sublethal effects of epoxiconazole on the earthworm Aporrectodea icterica.

    PubMed

    Pelosi, C; Lebrun, M; Beaumelle, L; Cheviron, N; Delarue, G; Nélieu, S

    2016-02-01

    Earthworms play a key role in agroecosystem soil processes. This study aims to assess the effects of different doses of a commercial formulation of epoxiconazole (Opus®), a persistent and widely used fungicide, on the earthworm Aporrectodea icterica. A laboratory study was conducted in a natural soil in order to measure effects of Opus® on earthworm mortality, uptake, weight gain, enzymatic activities (catalase and glutathione-S-transferase), and energy resources (lipids and glycogens). The estimated LC50 was 45.5 mg kg(-1), or 268 times the recommended dose. Weight gains were 28, 19, and 13% of the initial weight after 28 days of exposure in the control and D1 and D10 (1 and 10 times the recommended dose) treatments, respectively. No difference was observed for catalase activity between the three treatments, at 7, 14, or 28 days. The glutathion-S-transferase (GST) activity was two times as high in D1 as in D0 at 14 days. At 28 days, glycogen concentration was lower in D10 than in the D1 treatment. This study highlighted moderate sublethal effects of the commercial formulation Opus® for earthworms. Considering that these effects were observed on a species found in cultivated fields, even at recommended rates, much more attention should be paid to this pesticide. PMID:26081777

  19. ELECTROPHYSIOLOGICAL DETECTION OF SUBLETHAL NEUROTOXIC EFFECTS IN INTACT EARTHWORMS

    EPA Science Inventory

    The nervous system of earthworms is a logical site for studying the deleterious effects of many toxic substances because neural functions are often more sensitive to disruption than other physiological processes. However, the sublethal effects of toxicants on neural and behaviora...

  20. Impact of biochar on earthworm populations: A review

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Despite the overwhelming importance of earthworm activity in the soil system, there are a limited number of studies that have examined the impact resulting from biochar addition to soil. Biochar is part of the black carbon continuum of chemo-thermal converted biomass. This review summarizes existing...

  1. EARTHWORMS OF THE WESTERN UNITED STATES. PART 1. LUMBRICIDAE

    EPA Science Inventory

    The earthworm fauna of the western United States is an amalgam of native and introduced elements. While the native species are mostly members of the family Megascolecidae, and closely related to those of Australia and Southeast Asia, the introduced species are, at least in the No...

  2. TOXICITY OF METALS TO THE EARTHWORM 'EISENIA FETIDA'

    EPA Science Inventory

    Development of methods to measure the effect of man's residuals on soil ecosystems is desirable. Earthworms, as one of the largest and most easily obtained components of the soil biota, are suitable for evaluating perturbations to soil ecosystems. The impact of five metals (Cd, C...

  3. Partitioning of habitable pore space in earthworm burrows.

    PubMed

    Gorres, Josef H; Amador, Jose A

    2010-03-01

    Earthworms affect macro-pore structure of soils. However, some studies suggest that earthworm burrow walls and casts themselves differ greatly in structure from surrounding soils, potentially creating habitat for microbivorours nematodes which accelerate the decomposition and C and N mineralization. In this study aggregates were sampled from the burrow walls of the anecic earthworm Lumbricus terrestris and bulk soil (not altered by earthworms) from mesocosm incubated in the lab for 0, 1, 3, 5 and 16 weeks. Pore volumes and pore sizes were measured in triplicate with Mercury Intrusion Porosimetry (MIP). This method is well suited to establish pore size structure in the context of habitat, because it measures the stepwise intrusion of mercury from the outside of the aggregate into ever smaller pores. The progress of mercury into the aggregate interior thus resembles potential paths of a nematode into accessible habitable pore spaces residing in an aggregate. Total specific pore volume, V(s), varied between 0.13 and 0.18 mL/g and increased from 3 to 16 weeks in both burrow and bulk soil. Differences between total V(s) of bulk and burrow samples were not significant on any sampling date. However, differences were significant for pore size fractions at the scale of nematode body diameter. PMID:22736839

  4. {sup 32}P-postlabeling determination of DNA adducts in the earthworm Lumbricus terrestris exposed to PAH-contaminated soils

    SciTech Connect

    Walsh, P. |; El Adlouni, C.; Mukhopadhyay, M.J.; Nadeau, D.; Poirier, G.G.; Viel, G.

    1995-05-01

    The importance of the search for reliable biomarkers of DNA damage in environmental health assessment is well recognized by the scientific community and regulatory agencies. Among the major biomarkers of DNA damage is the measurement of DNA adducts in target cells or tissues. Up to now, DNA adduct determinations have been directed mostly toward human exposure to toxic substances from the workplace and environment. Moreover, techniques for measuring DNA adducts, and in particular the {sup 32}P-postlabelling technique, presented also the possibility of determining DNA adduct levels in endogenous animal populations exposed to polluted environments as early warning monitors of ecotoxicity. Soil contamination is becoming a major environmental issue. Therefore, numerous contaminated sites must now be remediated to protect human health and to permit new uses of these sites as agricultural, residential, or industrial areas. Fulfillment of this task requires standardized and sensitive bioassays to carry out site evaluations and to establish scientifically defensible soil quality criteria. To that effect, the earthworm appears to be one of the best organisms for use in soil toxicity evaluation. Earthworms are probably the most relevant soil species, representing 60 to 80% of the total animal biomass in soil. Present soil bioassays focus mostly on plant species with end points like seed germination, root elongation, seedling growth and seedling emergence, and on acute toxicity evaluation (re: LC 50) on the earthworm Eisenia fetida. As yet, a standardized soil invertebrate test for teratogenic or mutagenic end points has not been developed. In this paper, we report the feasibility of DNA adduct determination by {sup 32}P-postlabelling in the earthworm Lumbricus terrestris as a way to detect the presence of genotoxic substances in soils. 20 refs., 1 fig., 1 tab.

  5. Nontarget effects of ivermectin residues on earthworms and springtails dwelling beneath dung of treated cattle in four countries.

    PubMed

    Scheffczyk, Adam; Floate, Kevin D; Blanckenhorn, Wolf U; Düring, Rolf-Alexander; Klockner, Andrea; Lahr, Joost; Lumaret, Jean-Pierre; Salamon, Jörg-Alfred; Tixier, Thomas; Wohde, Manuel; Römbke, Jörg

    2016-08-01

    The authorization of veterinary medicinal products requires that they be assessed for nontarget effects in the environment. Numerous field studies have assessed these effects on dung organisms. However, few studies have examined effects on soil-dwelling organisms, which might be exposed to veterinary medicinal product residues released during dung degradation. The authors compared the abundance of earthworms and springtails in soil beneath dung from untreated cattle and from cattle treated 0 d, 3 d, 7 d, 14 d, and 28 d previously with ivermectin. Study sites were located in different ecoregions in Switzerland (Continental), The Netherlands (Atlantic), France (Mediterranean), and Canada (Northern Mixed Grassland). Samples were collected using standard methods from 1 mo to 12 mo after pat deposition. Ivermectin concentrations in soil beneath dung pats ranged from 0.02 mg/kg dry weight (3 mo) to typically <0.006 mg/kg dry weight (5-7 mo). Earthworms were abundant and species-rich at the Swiss and Dutch sites, less common with fewer species at the French site, and essentially absent at the Canadian site. Diverse but highly variable communities of springtails were present at all sites. Overall, results showed little effect of residues on either earthworms or springtails. The authors recommend that inclusion of soil organisms in field studies to assess the nontarget effects of veterinary medicinal products be required only if earthworms or springtails exhibit sensitivity to the product in laboratory tests. Environ Toxicol Chem 2016;35:1959-1969. © 2015 SETAC. PMID:26565894

  6. Immuno-Modulator Effects of Carbaryl and 2,4 D in theEarthworm Eisenia fetida andrei

    PubMed

    Ville; Roch; Cooper; Narbonne

    1997-04-01

    Carbaryl and 2,4 dichlorophenoxy acetic acid (2,4 D)exerted differential effects on the earthworm E. f. andrei functionsrelated to immuno defense. As determined by contact test assay, carbarylactivity is characterized by a low LC50 value of 3.4 &mgr;g/cm2,compared to 18 &mgr;g/cm2 for 2,4 D. Incubating earthworms withdoses of carbaryl as low as 0.1 &mgr;g/cm2 resulted in theinhibition of the lysozyme activity detected in the cytosol (CL). A stronginhibition of phagocytosis was also obtained but with 1.5&mgr;g/cm2. On the other hand, low doses of carbaryl significantlystimulated cytolysis (0.1 &mgr;g/cm2), serine protease activity (0.1&mgr;g/cm2) in the coelomic fluid (CF) and serine protease activityin the CL (0.05 &mgr;g/cm2). Concerning 2,4 D, both cytolysis in theCF and serine protease activity in the CL were stimulated by respectively 3.5&mgr;g/cm2 and 18 &mgr;g/cm2. Phagocytosis was inhibitedonly with 18 &mgr;g/cm2. Lysozyme and serine protease inhibitoractivities were not affected. The immuno toxicological assays we developed inearthworms, allow to distinguish between chemicals with differentimmuno-modulatory properties. Moreover, earthworms appear to be aparticularly well adapted sentinel organism for the evaluation of soilcontamination. PMID:9096078

  7. Avoidant personality disorder

    MedlinePlus

    ... Names Personality disorder - avoidant References American Psychiatric Association. Diagnostic and statistical manual of mental disorders. 5th ed. Arlington, VA: American Psychiatric Publishing. 2013. ...

  8. Mobilizing Communities to Implement Tested and Effective Programs to Help Youth Avoid Risky Behaviors: The Communities That Care Approach. Research Brief. Publication #2011-25

    ERIC Educational Resources Information Center

    Hawkins, J. David; Catalano, Richard F.; Kuklinski, Margaret R.

    2011-01-01

    Communities across the country have a vested interest in making sure that young people develop into healthy productive citizens and avoid behaviors that can jeopardize their own health and well-being and threaten the well-being of their families and neighborhoods as well. Substance abuse and delinquency are prime examples of behaviors that get in…

  9. Urban soil biomonitoring by beetle and earthworm populations

    SciTech Connect

    Janossy, L.; Bitto, A.

    1995-12-31

    Two macro invertebrate groups were chosen for biomonitoring environmental changes. The beetle population was pitfall trapped (five month in 1994) at five downtown sites (parks) of Budapest and in a hilly original woodland as a control site 33km NW of Budapest. Earthworms were collected by using formol solution. Five heavy metals were measured (Pb, Co, Hg, Zn, Cu) in the upper soil layer at the same sampling sites. Pb, Hg, Zn and Cu was over the tolerable limit in a park near the railway, extreme high Pb (530 mg/kg dry soil) and Zn content was measured in one park. Roads are also salted in wintertime. The number of beetle species in the downtown parks varied 10 to 22 (226--462 specimen). Near to the edge of the city up to 45 beetle species were found in a park with 1,027 specimen. In the woodland area 52 beetle species with 1,061 specimen were found. Less dominance and higher specific diversity showed the direction from downtown to woodland. Only 2 or 3 cosmopolitan earthworm species existed in downtown parks with 30--35 specimen/m{sup 2}, in the control woodland area 7 mostly endemic earthworm species were found with 74 specimens/m{sup 2}. But earthworm biomass was higher in three well fertilized parks (43--157 g/m{sup 2}), than in the original woodland (25-g/m{sup 2}). The beetle populations seem to be good tools for biomonitoring. Earthworms are susceptible to environmental changes but they also strongly depend on the leaf litter and the organic matter of the soil. The change in the animal populations is the result of summarized environmental impacts in such a big city like Budapest.

  10. Accumulation of heavy metals in the earthworm Eisenia foetida

    SciTech Connect

    Hartenstein, R.; Neuhauser, E.F.; Collier, J.

    1980-01-01

    Conversion of waste-activated sludge into egesta by the earthworm Eisenia foetida resulted in neither an increase nor decrease of 0.1 N HCl-extractable cadmium, copper, nickel, lead, or zinc. The addition of 2500 ppM copper as copper sulfate to activated sludge caused 100% mortality whthin 1 week, though feeding upon nonamended activated sludges with up to 1500 ppM copper over several months was innocuous. Amendment of sludge with 10, 50, and 100 ppM Cd as CdSO/sub 4/ resulted in 3.90-, 2.04-, and 1.44-fold concentrations in the earthworm over the quantities present in the sludge, with a range of 118 to 170 ppM being found on exposure to the highest level for periods of 1 to 5 weeks at 25/sup 0/C. In field trials with nonamended sludge, however, containing 12 to 27 ppM Cd, biweekly sampling for 28 weeks revealed accumulations in E. foetida ranging from 8 to 46 ppM; control earthworms not exposed to culture media with easily measurable Cd levels contained 0.3 to 2 ppM Cd. Upwards to about 50 ppM Ni, 325 ppM Pb, and 250 ppM Zn accumulated from sludges amended with ionic soluble forms of these metals. In the field, where these metals ranged from 2 to 46, 1 to 53, and 68 to 210 ppM, respectively, an upper concentration of about 50 ppM Ni, 55 ppM Pb, and 250 ppM Zn were found in the earthworm. Distinctions were made between accumulable and concentratable and a discussion is provided to show that each of the most problematic heavy metals, Cd, Zn, Ni, Pb, and Cu, may accumulate or concentrate in the earthworm.

  11. Aqueous and lipid nuclear magnetic resonance metabolomic profiles of the earthworm Aporrectodea caliginosa show potential as an indicator species for environmental metabolomics.

    PubMed

    Brown, Jeffrey N; Samuelsson, Linda; Bernardi, Giuliana; Gooneratne, Ravi; Larsson, D G Joakim

    2014-10-01

    The common pasture earthworm Aporrectodea caliginosa has often been neglected in environmental metabolomics in favor of species easily bred in the laboratory. The present study assigns aqueous metabolites in A. caliginosa using high-resolution 1- and 2-dimensional nuclear magnetic resonance (NMR) spectroscopy. In total, 51 aqueous metabolites were identified, including typical amino acids (alanine, leucine, asparagine, phenylalanine), sugars (maltose, glucose), the dominant earthworm-specific 2-hexyl-5-ethyl-furansulfonate, and several previously unreported metabolites (oxoglutarate, putrescine). Examining the lesser-known earthworm lipid metabolome showed various lipid fatty acyl chains, cholesterol, and phosphatidylcholine. To briefly test if the NMR metabolomic techniques could differentiate A. caliginosa from different sites, earthworms were collected from 2 adjacent farms. Orthogonal partial least squares discriminant analysis detected metabolomic differences, suggesting the worms from the 2 sites differed in their energy metabolism, as indicated by altered levels of alanine, glutamine, glutamate, malate, fumarate, and lipids. Evidence of greater utilization of lipid energy reserves and onset of protein catabolism was also present. While the precise cause of the metabolomic differences could not be determined, the results show the potential of this species for further environmental metabolomic studies. PMID:24995628

  12. Effects of dioxin exposure in Eisenia andrei: integration of biomarker data by an Expert System to rank the development of pollutant-induced stress syndrome in earthworms.

    PubMed

    Sforzini, Susanna; Dagnino, Alessandro; Oliveri, Laura; Canesi, Laura; Viarengo, Aldo

    2011-10-01

    A battery of biomarkers has recently been developed in the earthworm Eisenia andrei. In this study, different biomarkers (i.e. Ca²⁺-ATPase activity, lysosomal membrane stability-LMS, lysosomal lipofuscin and neutral lipid content) were utilized to evaluate the alterations in the physiological status of animals, induced by exposure for 3d to different sublethal concentrations of TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) (1.5 × 10⁻³, 1.5 × 10⁻², 1.5×10⁻¹ ng mL⁻¹) utilizing the paper contact toxicity test. Lysosome/cytoplasm volume ratio and DNA damage were also evaluated as a biomarker at the tissue level and as a biomarker of genotoxicity, respectively. Moreover, the NR retention time assay conditions were optimized for the determination of in vivo LMS in earthworm coelomocytes. The results demonstrate that LMS and Ca²⁺-ATPase activity were early warning biomarkers able to detect the effects of minimal amounts of TCDD and that biomarkers evaluated at the tissue level are important for following the evolution of the stress syndrome in earthworms. To evaluate the health status of the animals, an Earthworm Expert System (EES) for biomarker data integration and interpretation was developed. The EES proved to be a suitable tool able to rank, objectively, the different levels of the stress syndrome in E. andrei induced by the different concentrations of TCDD. PMID:21777938

  13. Assessing the ecotoxicological effects of long-term contaminated mine soils on plants and earthworms: relevance of soil (total and available) and body concentrations.

    PubMed

    García-Gómez, Concepción; Esteban, Elvira; Sánchez-Pardo, Beatriz; Fernández, María Dolores

    2014-09-01

    The interactions and relevance of the soil (total and available) concentrations, accumulation, and acute toxicity of several essential and non-essential trace elements were investigated to determine their importance in environmental soil assessment. Three plant species (T. aestivum, R. sativum, and V. sativa) and E. fetida were simultaneously exposed for 21 days to long-term contaminated soils collected from the surroundings of an abandoned pyrite mine. The soils presented different levels of As and metals, mainly Zn and Cu, and were tested at different soil concentrations [12.5, 25, 50, and 100% of contaminated soil/soil (w/w)] to increase the range of total and available soil concentrations necessary for the study. The total concentrations in the soils (of both As and metals) were better predictors of earthworm uptake than were the available concentrations. In plants, the accumulation of metals was related to the available concentrations of Zn and Cu, which could indicate that plants and earthworms accumulate elements from different pools of soil contaminants. Moreover, Zn and Cu, which are essential elements, showed controlled uptake at low concentrations. The external metal concentrations predicted earthworm mortality, whereas in plants, the effects on growth were correlated to the As and metal contents in the plants. In general, the bioaccumulation factors were lower at higher exposure levels, which implies the existence of auto-regulation in the uptake of both essential and non-essential elements by plants and earthworms. PMID:24875255

  14. Evidence for human-mediated dispersal of exotic earthworms: support for exploring strategies to limit further spread.

    PubMed

    Hale, Cindy M

    2008-03-01

    As potent ecosystem engineers, non-native earthworms are altering the fundamental structure and function of previously earthworm-free cold-temperate hardwood forests in North America. Discarded earthworms used for fishing bait has been presumed to be an important vector for the continued spread of non-native earthworms because epicentres of invasion often include boat landings, lakeshores and roads. However, controversy has remained about the overall importance of human-mediated spread vs. natural expansion of established earthworm populations. In this issue of Molecular Ecology, Cameron et al. explore the continued role of humans in dispersing non-native earthworms. PMID:18302681

  15. Usability testing of Avoiding Diabetes Thru Action Plan Targeting (ADAPT) decision support for integrating care-based counseling of pre-diabetes in an electronic health record

    PubMed Central

    Chrimes, Dillon; Kushniruk, Andre; Kitos, Nicole R.

    2014-01-01

    Purpose Usability testing can be used to evaluate human computer interaction (HCI) and communication in shared decision making (SDM) for patient-provider behavioral change and behavioral contracting. Traditional evaluations of usability using scripted or mock patient scenarios with think-aloud protocol analysis provide a to identify HCI issues. In this paper we describe the application of these methods in the evaluation of the Avoiding Diabetes Thru Action Plan Targeting (ADAPT) tool, and test the usability of the tool to support the ADAPT framework for integrated care counseling of pre-diabetes. The think-aloud protocol analysis typically does not provide an assessment of how patient-provider interactions are effected in “live” clinical workflow or whether a tool is successful. Therefore, “Near-live” clinical simulations involving applied simulation methods were used to compliment the think-aloud results. This complementary usability technique was used to test the end-user HCI and tool performance by more closely mimicking the clinical workflow and capturing interaction sequences along with assessing the functionality of computer module prototypes on clinician workflow. We expected this method to further complement and provide different usability findings as compared to think-aloud analysis. Together, this mixed method evaluation provided comprehensive and realistic feedback for iterative refinement of the ADAPT system prior to implementation. Methods The study employed two phases of testing of a new interactive ADAPT tool that embedded an evidence-based shared goal setting component into primary care workflow for dealing with pre-diabetes counseling within a commercial physician office electronic health record (EHR). Phase I applied usability testing that involved “think-aloud” protocol analysis of 8 primary care providers interacting with several scripted clinical scenarios. Phase II used “near-live” clinical simulations of 5 providers

  16. Toxicity of AMPA to the earthworm Eisenia andrei Bouché, 1972 in tropical artificial soil.

    PubMed

    Domínguez, Anahí; Brown, George Gardner; Sautter, Klaus Dieter; de Oliveira, Cintia Mara Ribas; de Vasconcelos, Eliane Carvalho; Niva, Cintia Carla; Bartz, Marie Luise Carolina; Bedano, José Camilo

    2016-01-01

    Aminomethylphosphonic acid (AMPA) - one of glyphosate's main metabolites - has been classified as persistent in soils, raising concern regarding the widespread use of glyphosate in agriculture and forestry. Glyphosate may have negative or neutral effects on soil biota, but no information is available on the toxicity of AMPA to soil invertebrates. Therefore our aim was to study the effect of AMPA on mortality and reproduction of the earthworm species Eisenia andrei using standard soil ecotoxicological methods (ISO). Field-relevant concentrations of AMPA had no significant effects on mortality in acute or chronic assays. Except at the highest concentration tested, a significant biomass loss was observed compared to controls in the chronic assay. The number of juveniles and cocoons increased with higher concentrations of AMPA applied, but their mean weights decreased. This mass loss indicates higher sensitivity of juveniles than adults to AMPA. Our results suggest that earthworms coming from parents grown in contaminated soils may have reduced growth, limiting their beneficial roles in key soil ecosystem functions. Nevertheless, further research is needed to better understand the mechanisms underlying the sublethal effects observed here. PMID:26792548

  17. Toxicity of AMPA to the earthworm Eisenia andrei Bouché, 1972 in tropical artificial soil

    PubMed Central

    Domínguez, Anahí; Brown, George Gardner; Sautter, Klaus Dieter; Ribas de Oliveira, Cintia Mara; de Vasconcelos, Eliane Carvalho; Niva, Cintia Carla; Bartz, Marie Luise Carolina; Bedano, José Camilo

    2016-01-01

    Aminomethylphosphonic acid (AMPA) - one of glyphosate’s main metabolites - has been classified as persistent in soils, raising concern regarding the widespread use of glyphosate in agriculture and forestry. Glyphosate may have negative or neutral effects on soil biota, but no information is available on the toxicity of AMPA to soil invertebrates. Therefore our aim was to study the effect of AMPA on mortality and reproduction of the earthworm species Eisenia andrei using standard soil ecotoxicological methods (ISO). Field-relevant concentrations of AMPA had no significant effects on mortality in acute or chronic assays. Except at the highest concentration tested, a significant biomass loss was observed compared to controls in the chronic assay. The number of juveniles and cocoons increased with higher concentrations of AMPA applied, but their mean weights decreased. This mass loss indicates higher sensitivity of juveniles than adults to AMPA. Our results suggest that earthworms coming from parents grown in contaminated soils may have reduced growth, limiting their beneficial roles in key soil ecosystem functions. Nevertheless, further research is needed to better understand the mechanisms underlying the sublethal effects observed here. PMID:26792548

  18. Effects of PAHs and dioxins on the earthworm Eisenia andrei: a multivariate approach for biomarker interpretation.

    PubMed

    Sforzini, Susanna; Moore, Michael N; Boeri, Marta; Bencivenga, Mauro; Viarengo, Aldo

    2015-01-01

    In this study, a battery of biomarkers was utilised to evaluate the stress syndrome induced in the earthworm Eisenia andrei by exposure to environmentally realistic concentrations of benzo[a]pyrene (B[a]P) and 2,3,7,8-tetrachlorodibenzo-para-dioxin (TCDD) in OECD soil. The set of tests was then employed to assess the toxicity of field soils contaminated with organic xenobiotic compounds (such as PAHs, dioxins and PCBs). The results highlighted an impairment of immune and metabolic functions and genotoxic damage in worms exposed also to lower bioavailable concentrations of toxic chemicals. Multivariate analysis of biomarker data showed that all different contaminated soils had a detrimental effect on the earthworms. A separation between temporal and concentration factors was also evident for B[a]P and TCDD treatments; and field contaminated soils were further differentiated reflecting a diverse contamination. Multivariate analysis also demonstrated that lysosomal membrane stability can be considered a prognostic indicator for worm health status. PMID:25305466

  19. Ternary toxicological interactions of insecticides, herbicides, and a heavy metal on the earthworm Eisenia fetida.

    PubMed

    Wang, Yanhua; Chen, Chen; Qian, Yongzhong; Zhao, Xueping; Wang, Qiang

    2015-03-01

    The combined toxicities of five insecticides (chlorpyrifos, avermectin, imidacloprid, λ-cyhalothrin, and phoxim), two herbicides (atrazine and butachlor), and a heavy metal (cadmium) have been examined using the acute toxicity test on the earthworm. With a concentration of 2.75 mg/kg being lethal for 50% of the organisms, imidacloprid exhibited the highest acute toxicity toward the earthworm Eisenia fetida. Toxicological interactions of these chemicals in ternary mixtures were studied using the combination-index (CI) equation method. Twenty-one ternary mixtures exhibited various interactive effects, in which 11 combinations showed synergistic effects, four led to dual synergistic/additive behaviors, one exhibited an additive effect, and five showed increasing antagonism within the entire range of effects. The CI method was compared with the classical models of concentration addition and independent action, and it was found that the CI method could accurately predict combined toxicity of the chemicals studied. The predicted synergism in the majority of the mixtures, especially at low-effect levels, might have implications in the real terrestrial environment. PMID:25463238

  20. Establishing principal soil quality parameters influencing earthworms in urban soils using bioassays.

    PubMed

    Hankard, Peter K; Bundy, Jacob G; Spurgeon, David J; Weeks, Jason M; Wright, Julian; Weinberg, Claire; Svendsen, Claus

    2005-01-01

    Potential contamination at ex-industrial sites means that, prior to change of use, it will be necessary to quantify the extent of risks to potential receptors. To assess ecological hazards, it is often suggested to use biological assessment to augment chemical analyses. Here we investigate the potential of a commonly recommended bioassay, the earthworm reproduction test, to assess the status of urban contaminated soils. Sample points at all study sites had contaminant concentrations above the Dutch soil criteria Target Values. In some cases, the relevant Intervention Values were exceeded. Earthworm survival at most points was high, but reproduction differed significantly in soil from separate patches on the same site. When the interrelationships between soil parameters and reproduction were studied, it was not possible to create a good model of site soil toxicity based on single or even multiple chemical measurements of the soils. We thus conclude that chemical analysis alone is not sufficient to characterize soil quality and confirms the value of biological assays for risk assessment of potentially contaminated soils. PMID:15519451

  1. Avoidable mortality in Lithuania.

    PubMed Central

    Gaizauskiene, A; Gurevicius, R

    1995-01-01

    STUDY OBJECTIVE--The study aimed to analyse avoidable mortality in Lithuania as an index of the quality of health care and to assess trends in avoidable mortality from 1970-90. SETTING AND PARTICIPANTS--All deaths of Lithuanian residents aged between 0 and 64 years between 1970 and 1990 were analysed. MEASUREMENTS AND MAIN RESULTS--Twenty seven per cent of all deaths in this age group were avoidable. Avoidable deaths were grouped into preventable and treatable ones. Treatable causes of death accounted for 54%, and preventable, 46% of avoidable mortality. Time trends showed that general mortality and mortality from avoidable causes of death in this age group were almost stable between 1970 and 1990. Mortality from treatable causes of death fell, while deaths from preventable causes increased. The results in the preventable group were greatly affected by deaths from malignant neoplasms of trachea, bronchus, and lungs. Differences were noted between the sexes in total mortality as well as in avoidable mortality. CONCLUSIONS--Avoidable causes of death are relatively common and, consequently, they are of practical importance for public health and studies of the health care quality in Lithuania. Reorganisation of health care is to be carried out and considerable emphasis will be placed on health education, promotion, and prevention, as primary prevention measures have not been effective thus far. PMID:7629464

  2. Avoiding Statistical Mistakes

    ERIC Educational Resources Information Center

    Strasser, Nora

    2007-01-01

    Avoiding statistical mistakes is important for educators at all levels. Basic concepts will help you to avoid making mistakes using statistics and to look at data with a critical eye. Statistical data is used at educational institutions for many purposes. It can be used to support budget requests, changes in educational philosophy, changes to…

  3. Earthworms facilitate carbon sequestration through unequal amplification of carbon stabilization compared with mineralization

    NASA Astrophysics Data System (ADS)

    Zhang, Weixin; Hendrix, Paul F.; Dame, Lauren E.; Burke, Roger A.; Wu, Jianping; Neher, Deborah A.; Li, Jianxiong; Shao, Yuanhu; Fu, Shenglei

    2013-10-01

    A recent review concluded that earthworm presence increases CO2 emissions by 33% but does not affect soil organic carbon stocks. However, the findings are controversial and raise new questions. Here we hypothesize that neither an increase in CO2 emission nor in stabilized carbon would entirely reflect the earthworms’ contribution to net carbon sequestration. We show how two widespread earthworm invaders affect net carbon sequestration through impacts on the balance of carbon mineralization and carbon stabilization. Earthworms accelerate carbon activation and induce unequal amplification of carbon stabilization compared with carbon mineralization, which generates an earthworm-mediated ‘carbon trap’. We introduce the new concept of sequestration quotient to quantify the unequal processes. The patterns of CO2 emission and net carbon sequestration are predictable by comparing sequestration quotient values between treatments with and without earthworms. This study clarifies an ecological mechanism by which earthworms may regulate the terrestrial carbon sink.

  4. Earthworm effects on gaseous emissions during vermifiltration of pig fresh slurry.

    PubMed

    Luth; Robin, Paul; Germain, Philippe; Lecomte, Marcel; Landrain, Brigitte; Li, Yinsheng; Cluzeau, Daniel

    2011-02-01

    Treatment of liquid manure can result in the production of ammonia, nitrous oxide and methane. Earthworms mix and transform nitrogen and carbon without consuming additional energy. The objective of this paper is to analyse whether earthworms modify the emissions of NH(3), N(2)O, CH(4) and CO(2) during vermifiltration of pig slurry. The experiment used mesocosms of around 50 L, made from a vermifilter treating the diluted manure of a swine house. Three levels of slurry were added to the mesocosms, with or without earthworms, during one month, in triplicate. Earthworm abundance and gas emissions were measured three and five times, respectively. There was a decrease in emissions of ammonia and nitrous oxide and a sink of methane in treatments with earthworms. We suggest that earthworm abundance can be used as a bioindicator of low energy input, and low greenhouse gas and ammonia output in systems using fresh slurry with water recycling. PMID:21185175

  5. Effect of earthworm feeding guilds on ingested dissimilatory nitrate reducers and denitrifiers in the alimentary canal of the earthworm.

    PubMed

    Depkat-Jakob, Peter S; Hilgarth, Maik; Horn, Marcus A; Drake, Harold L

    2010-09-01

    The earthworm gut is an anoxic nitrous oxide (N(2)O)-emitting microzone in aerated soils. In situ conditions of the gut might stimulate ingested nitrate-reducing soil bacteria linked to this emission. The objective of this study was to determine if dissimilatory nitrate reducers and denitrifiers in the alimentary canal were affected by feeding guilds (epigeic [Lumbricus rubellus], anecic [Lumbricus terrestris], and endogeic [Aporrectodea caliginosa]). Genes and gene transcripts of narG (encodes a subunit of nitrate reductase and targets both dissimilatory nitrate reducers and denitrifiers) and nosZ (encodes a subunit of N(2)O reductase and targets denitrifiers) were detected in guts and soils. Gut-derived sequences were similar to those of cultured and uncultured soil bacteria and to soil-derived sequences obtained in this study. Gut-derived narG sequences and narG terminal restriction fragments (TRFs) were affiliated mainly with Gram-positive organisms (Actinobacteria). The majority of gut- and uppermost-soil-derived narG transcripts were affiliated with Mycobacterium (Actinobacteria). In contrast, narG sequences indicative of Gram-negative organisms (Proteobacteria) were dominant in mineral soil. Most nosZ sequences and nosZ TRFs were affiliated with Bradyrhizobium (Alphaproteobacteria) and uncultured soil bacteria. TRF profiles indicated that nosZ transcripts were more affected by earthworm feeding guilds than were nosZ genes, whereas narG transcripts were less affected by earthworm feeding guilds than were narG genes. narG and nosZ transcripts were different and less diverse in the earthworm gut than in mineral soil. The collective results indicate that dissimilatory nitrate reducers and denitrifiers in the earthworm gut are soil derived and that ingested narG- and nosZ-containing taxa were not uniformly stimulated in the guts of worms from different feeding guilds. PMID:20656855

  6. Accumulation of methylmercury in the earthworm, Eisenia foetida, and its effect on regeneration

    SciTech Connect

    Beyer, W.N.; Cromartie, E.; Moment, G.B.

    1985-08-01

    Earthworms provide an appropriate model for evaluating the environmental hazards of metals in soil, and they are also excellent organisms for studying the process of regeneration. Two studies have found that concentrations of mercury in earthworms were higher than those in the soil where they lived. This study investigates the accumulation of methylmercury in the earthworm, Eisenia foetida (Savigny), and its effect on regeneration after excision of the caudal end.

  7. Earthworm transport of heavy metals from sewage sludge: a micro-PIXE application in soil science

    NASA Astrophysics Data System (ADS)

    Protz, R.; Teesdale, W. J.; Maxwell, J. A.; Campbell, J. L.; Duke, C.

    1993-05-01

    Micro-PIXE was used to analyze earthworm fecal material and the linings of earthworm channels in the soil below a land area on which sewage sludge had been applied. Metals present in the sludge were identified both in fecal pellets and in the linings of the channels, at concentration markedly higher than in the soil matrix. PIXE elemental data in raster format were spatially analyzed during image analysis demonstrating in a quantitative manner the spatial correlations among elements transported by the earthworms.

  8. Belowground interactions with aboveground consequences: Invasive earthworms and arbuscular mycorrhizal fungi.

    PubMed

    Paudel, Shishir; Longcore, Travis; MacDonald, Beau; McCormick, Melissa K; Szlavecz, Katalin; Wilson, Gail W T; Loss, Scot R

    2016-03-01

    A mounting body of research suggests that invasive nonnative earthworms substantially alter microbial communities, including arbuscular mycorrhizal fungi (AMF). These changes to AMF can cascade to affect plant communities and vertebrate populations. Despite these research advances, relatively little is known about (1) the mechanisms behind earthworms' effects on AMF and (2) the factors that determine the outcomes of earthworm-AMF interactions (i.e., whether AMF abundance is increased or decreased and subsequent effects on plants). We predict that AMF-mediated effects of nonnative earthworms on ecosystems are nearly universal because (1) AMF are important components of most terrestrial ecosystems, (2) nonnative earthworms have become established in nearly every type of terrestrial ecosystem, and (3) nonnative earthworms, due to their burrowing and feeding behavior, greatly affect AMF with potentially profound concomitant effects on plant communities. We highlight the multiple direct and indirect effects of nonnative earthworms on plants and review what is currently known about the interaction between earthworms and AMF. We also illustrate how the effects of nonnative earthworms on plant-AMF mutualisms can alter the structure and stability of aboveground plant communities, as well as the vertebrate communities relying on these habitats. Integrative studies that assess the interactive effects of earthworms and AMF can provide new insights into the role that belowground ecosystem engineers play in altering aboveground ecological processes. Understanding these processes may improve our ability to predict the structure of plant and animal communities in earthworm-invaded regions and to develop management strategies that limit the numerous undesired impacts of earthworms. PMID:27197388

  9. New earthworm records from Turkey, with description of three new species (Oligochaeta: Lumbricidae).

    PubMed

    Szederjesi, Tímea; Pavlíček, Tomás; Coşkun, Yüksel; Csuzdi, Csaba

    2014-01-01

    Identifying the earthworm material recently collected in different parts of Turkey (Marmara Region, Upper Mesopotamia, Hatay Province and East Anatolia) resulted in records of 29 earthworm species including three lumbricids new to science: Dendrobaena cevdeti, D. szalokii and Eisenia patriciae spp. nov. In addition, Dendrobaena cognettii is reported for the first time from the country. With this contribution, the number of earthworm species and subspecies registered in Turkey is raised to 80. PMID:24870656

  10. Vermicomposting of Solid Waste Using Local and Exotic Earthworms: A Comparative Study.

    PubMed

    Amit, Krishan; Ajit, Kumar; Arthanareeswari, M; Kamaraj, P

    2014-07-01

    The aim of this study was to assess the decomposition efficiency of earthworms, local (L.mauritii) as well as exotic (Eisenia foetida) in vermicomposting of garden litter in SRM University campus. The vermicompost produced through vermicomposting of garden litter mixed with cow dung in the ratio of 3:1 by using local and exotic earthworms (Eisenia foetida) was rich in ammoniacal nitrogen, nitrate nitrogen, available phosphorus, total potassium and TKN, and there was a reduction in total organic carbon and carbon to nitrogen ratio. The study reveals that the decomposition efficiency of exotic earthworms is better compared to local earthworms. PMID:26563089

  11. Bioaccumulation and enantioselectivity of type I and type II pyrethroid pesticides in earthworm.

    PubMed

    Chang, Jing; Wang, Yinghuan; Wang, Huili; Li, Jianzhong; Xu, Peng

    2016-02-01

    In this study, the bioavailability and enantioselectivity differences between bifenthrin (BF, typeⅠpyrethroid) and lambad-cyhalothrin (LCT, type Ⅱ pyrethroid) in earthworm (Eisenia fetida) were investigated. The bio-soil accumulation factors (BSAFs) of BF was about 4 times greater than that of LCT. LCT was degraded faster than BF in soil while eliminated lower in earthworm samples. Compound sorption plays an important role on bioavailability in earthworm, and the soil-adsorption coefficient (K(oc)) of BF and LCT were 22 442 and 42 578, respectively. Metabolic capacity of earthworm to LCT was further studied as no significant difference in the accumulation of LCT between the high and low dose experiment was found. 3-phenoxybenzoic acid (PBCOOH), a metabolite of LCT produced by earthworm was detected in soil. The concentration of PBCOOH at high dose exposure was about 4.7 times greater than that of in low dose level at the fifth day. The bioaccumulation of BF and LCT were both enantioselective in earthworm. The enantiomer factors of BF and LCT in earthworm were approximately 0.12 and 0.65, respectively. The more toxic enantiomers ((+)-BF and (-)-LCT) had a preferential degradation in earthworm and leaded to less toxicity on earthworm for racemate exposure. In combination with other studies, a liner relationship between Log BSAF(S) and Log K(ow) was observed, and the Log BSAF(S) decreased with the increase of Log K(ow). PMID:26490429

  12. Avoiding Computer Viruses.

    ERIC Educational Resources Information Center

    Rowe, Joyce; And Others

    1989-01-01

    The threat of computer sabotage is a real concern to business teachers and others responsible for academic computer facilities. Teachers can minimize the possibility. Eight suggestions for avoiding computer viruses are given. (JOW)

  13. [Effects of low dosage pyrene pollution on biochemical characters of earthworm (Eisenia fetida) in soil].

    PubMed

    Zhang, Wei; Song, Yu-Fang; Sun, Tie-Heng; Liu, Miao; Ackland, M L; Galina, Belogolova

    2007-09-01

    By the method of artificial soil pollution, an exposure experiment with different concentrations of pyrene (0, 60, 120, 240, 480, 960 microg x kg(-1)) was conducted to determine the cytochrome P450 and MDA contents and the glutathione-S-transferase (GST), superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities in earthworm gut after exposure for 1, 3, 7 and 14 days. The results indicated that within the range of test pyrene concentrations, all the biochemical indices tested differed in their sensitivity to pyrene toxicity, among which, P450 content and GST and SOD activities were most sensitive, followed by POD and CAT activities, while MDA content did not show any obvious response. Exposure duration had stronger effects than exposure dosage. In diagnosing the ecotoxicity of soil pollutant, it could be necessary to use a combined multi-time and multi-index diagnostic method to enhance the sensitivity and effectiveness of the indices adopted. PMID:18062320

  14. Avoided Crossing and Synchronization

    NASA Astrophysics Data System (ADS)

    Sekii, T.; Shibahashi, H.

    2013-12-01

    We examine avoided crossing of stellar pulsations in the nonlinear regime, where synchronization may occur, based on a simple model of weakly coupled van der Pol oscillators with close frequencies. For this simple case, avoided crossing is unaffected in the sense that there is a frequency difference between the symmetric and antisymmetric modes, but as a result of synchronization, unlike the linear oscillations case, the system can vibrate in only one of the modes.

  15. Operational Collision Avoidance

    NASA Technical Reports Server (NTRS)

    Guit, Bill

    2015-01-01

    This presentation will describe the early days of the EOS Aqua and Aura operational collision avoidance process. It will highlight EOS debris avoidance maneuvers, EOS high interest event statistic and A-Train systematic conjunctions and conclude with future challenges. This is related to earlier e-DAA (tracking number 21692) that an abstract was submitted to a different conference. Eric Moyer, ESMO Deputy Project Manager has reviewed and approved this presentation on May 6, 2015

  16. Elimination kinetic model for organic chemicals in earthworms.

    PubMed

    Dimitrova, N; Dimitrov, S; Georgieva, D; Van Gestel, C A M; Hankard, P; Spurgeon, D; Li, H; Mekenyan, O

    2010-08-15

    Mechanistic understanding of bioaccumulation in different organisms and environments should take into account the influence of organism and chemical depending factors on the uptake and elimination kinetics of chemicals. Lipophilicity, metabolism, sorption (bioavailability) and biodegradation of chemicals are among the important factors that may significantly affect the bioaccumulation process in soil organisms. This study attempts to model elimination kinetics of organic chemicals in earthworms by accounting for the effects of both chemical and biological properties, including metabolism. The modeling approach that has been developed is based on the concept for simulating metabolism used in the BCF base-line model developed for predicting bioaccumulation in fish. Metabolism was explicitly accounted for by making use of the TIMES engine for simulation of metabolism and a set of principal transformations. Kinetic characteristics of transformations were estimated on the basis of observed kinetics data for the elimination of organic chemicals from earthworms. PMID:20185163

  17. Differential expression of three labial genes during earthworm head regeneration.

    PubMed

    Cho, Sung-Jin; Koh, Ki Seok; Lee, Eun; Park, Soon Cheol

    2009-12-01

    The earthworm provides an excellent model for investigating regeneration. Here we report the full-length cloning of three labial genes (Pex-lab01, Pex-lab02, and Pex-lab03) in the earthworm Perionyx excavatus. To analyze their expression pattern during head and tail regeneration, we used the reverse transcription-polymerase chain reaction. Our results indicate that the three labial genes were expressed only in the head-regenerating tissues. Also, we found that the expression of Pex-lab01 and Pex-lab02 is up-regulated, and this indicates their involvement in wound healing and the blastema formation processes during early head regeneration. PMID:19966495

  18. Patterns of litter disappearance in a northern hardwood forest invaded by exotic earthworms.

    PubMed

    Suárez, Esteban R; Fahey, Timothy J; Yavitt, Joseph B; Groffman, Peter M; Bohlen, Patrick J

    2006-02-01

    A field study was conducted to evaluate the effects of exotic earthworm invasions on the rates of leaf litter disappearance in a northern hardwood forest in southcentral New York, USA. Specifically, we assessed whether differences in litter quality and the species composition of exotic earthworm communities affected leaf litter disappearance rates. Two forest sites with contrasting communities of exotic earthworms were selected, and disappearance rates of sugar maple and red oak litter were estimated in litter boxes in adjacent earthworm-free, transition, and earthworm-invaded plots within each site. After 540 days in the field, 1.7-3 times more litter remained in the reference plots than in the earthworm-invaded plots. In the earthworm-invaded plots, rates of disappearance of sugar maple litter were higher than for oak litter during the first year, but by the end of the experiment, the amount of sugar maple and oak litter remaining in the earthworm-invaded plots was identical within each site. The composition of the earthworm communities significantly affected the patterns of litter disappearance. In the site dominated by the anecic earthworm Lumbricus terrestris and the endogeic Aporrectodea tuberculata, the percentage of litter remaining after 540 days (approximately 17%) was significantly less than at the site dominated by L. rubellus and Octolasion tyrtaeum (approximately 27%). This difference may be attributed to the differences in feeding behavior of the two litter-feeding species: L. terrestris buries entire leaves in vertical burrows, whereas L. rubellus usually feeds on litter at the soil surface, leaving behind leaf petioles and veins. Our results showed that earthworms not only accelerate litter disappearance rates, but also may reduce the differences in decomposition rates that result from different litter qualities at later stages of decay. Similarly, our results indicate that earthworm effects on decomposition vary with earthworm community

  19. Proximal Soil Sensing – A Contribution for Species Habitat Distribution Modelling of Earthworms in Agricultural Soils?

    PubMed Central

    Schirrmann, Michael; Joschko, Monika; Gebbers, Robin; Kramer, Eckart; Zörner, Mirjam; Barkusky, Dietmar; Timmer, Jens

    2016-01-01

    Background Earthworms are important for maintaining soil ecosystem functioning and serve as indicators of soil fertility. However, detection of earthworms is time-consuming, which hinders the assessment of earthworm abundances with high sampling density over entire fields. Recent developments of mobile terrestrial sensor platforms for proximal soil sensing (PSS) provided new tools for collecting dense spatial information of soils using various sensing principles. Yet, the potential of PSS for assessing earthworm habitats is largely unexplored. This study investigates whether PSS data contribute to the spatial prediction of earthworm abundances in species distribution models of agricultural soils. Methodology/Principal Findings Proximal soil sensing data, e.g., soil electrical conductivity (EC), pH, and near infrared absorbance (NIR), were collected in real-time in a field with two management strategies (reduced tillage / conventional tillage) and sandy to loam soils. PSS was related to observations from a long-term (11 years) earthworm observation study conducted at 42 plots. Earthworms were sampled from 0.5 x 0.5 x 0.2 m³ soil blocks and identified to species level. Sensor data were highly correlated with earthworm abundances observed in reduced tillage but less correlated with earthworm abundances observed in conventional tillage. This may indicate that management influences the sensor-earthworm relationship. Generalized additive models and state-space models showed that modelling based on data fusion from EC, pH, and NIR sensors produced better results than modelling without sensor data or data from just a single sensor. Regarding the individual earthworm species, particular sensor combinations were more appropriate than others due to the different habitat requirements of the earthworms. Earthworm species with soil-specific habitat preferences were spatially predicted with higher accuracy by PSS than more ubiquitous species. Conclusions/Significance Our

  20. Plasmid Transfer between Spatially Separated Donor and Recipient Bacteria in Earthworm-Containing Soil Microcosms

    PubMed Central

    Daane, L. L.; Molina, J.; Sadowsky, M. J.

    1997-01-01

    Most gene transfer studies have been performed with relatively homogeneous soil systems in the absence of soil macrobiota, including invertebrates. In this study we examined the influence of earthworm activity (burrowing, casting, and feeding) on transfer of plasmid pJP4 between spatially separated donor (Alcaligenes eutrophus) and recipient (Pseudomonas fluorescens) bacteria in nonsterile soil columns. A model system was designed such that the activity of earthworms would act to mediate cell contact and gene transfer. Three different earthworm species (Aporrectodea trapezoides, Lumbricus rubellus, and Lumbricus terrestris), representing each of the major ecological categories (endogeic, epigeic, and anecic), were evaluated. Inoculated soil microcosms, with and without added earthworms, were analyzed for donor, recipient, and transconjugant bacteria at 5-cm-depth intervals by using selective plating techniques. Transconjugants were confirmed by colony hybridization with a mer gene probe. The presence of earthworms significantly increased dispersal of the donor and recipient strains. In situ gene transfer of plasmid pJP4 from A. eutrophus to P. fluorescens was detected only in earthworm-containing microcosms, at a frequency of (symbl)10(sup2) transconjugants per g of soil. The depth of recovery was dependent on the burrowing behavior of each earthworm species; however, there was no significant difference in the total number of transconjugants among the earthworm species. Donor and recipient bacteria were recovered from earthworm feces (casts) of all three earthworm species, with numbers up to 10(sup6) and 10(sup4) bacteria per g of cast, respectively. A. trapezoides egg capsules (cocoons) formed in the inoculated soil microcosms contained up to 10(sup7) donor and 10(sup6) recipient bacteria per g of cocoon. No transconjugant bacteria, however, were recovered from these microhabitats. To our knowledge, this is the first report of gene transfer between physically

  1. Earthworm-Mycorrhiza Interactions Can Affect the Diversity, Structure and Functioning of Establishing Model Grassland Communities

    PubMed Central

    Zaller, Johann G.; Heigl, Florian; Grabmaier, Andrea; Lichtenegger, Claudia; Piller, Katja; Allabashi, Roza; Frank, Thomas; Drapela, Thomas

    2011-01-01

    Both earthworms and arbuscular mycorrhizal fungi (AMF) are important ecosystem engineers co-occurring in temperate grasslands. However, their combined impacts during grassland establishment are poorly understood and have never been studied. We used large mesocosms to study the effects of different functional groups of earthworms (i.e., vertically burrowing anecics vs. horizontally burrowing endogeics) and a mix of four AMF taxa on the establishment, diversity and productivity of plant communities after a simulated seed rain of 18 grassland species comprising grasses, non-leguminous forbs and legumes. Moreover, effects of earthworms and/or AMF on water infiltration and leaching of ammonium, nitrate and phosphate were determined after a simulated extreme rainfall event (40 l m−2). AMF colonisation of all three plant functional groups was altered by earthworms. Seedling emergence and diversity was reduced by anecic earthworms, however only when AMF were present. Plant density was decreased in AMF-free mesocosms when both anecic and endogeic earthworms were active; with AMF also anecics reduced plant density. Plant shoot and root biomass was only affected by earthworms in AMF-free mesocosms: shoot biomass increased due to the activity of either anecics or endogeics; root biomass increased only when anecics were active. Water infiltration increased when earthworms were present in the mesocosms but remained unaffected by AMF. Ammonium leaching was increased only when anecics or a mixed earthworm community was active but was unaffected by AMF; nitrate and phosphate leaching was neither affected by earthworms nor AMF. Ammonium leaching decreased with increasing plant density, nitrate leaching decreased with increasing plant diversity and density. In order to understand the underlying processes of these interactions further investigations possibly under field conditions using more diverse belowground communities are required. Nevertheless, this study demonstrates that

  2. Intensified Weathering Control of Carbon Cycle along an Earthworm Invasion Chronosequence: Preliminary Data

    NASA Astrophysics Data System (ADS)

    Fernandez, C.; Yoo, K.; Aufdenkampe, A. K.; Hale, C.

    2009-12-01

    Though earthworms may appear ubiquitous and native where they are found, this is not true in the Glaciated areas of North America. After the glacial retreat, earthworms were not able to catch up with the northward expansion of forests. Subsequently, these forests in the glaciated areas have developed without native earthworm species over the past six to ten thousand years. With the arrival of agriculture, fishing villages, and expansion of unpaved roads, exotic earthworm species began to invade the adjacent forests. We focus on a well studied earthworm invasion chronosequence in the Chippewa National Forest in Minnesota. The chronosequence is ~100 meter long, which represents several decades of invasion history. In general, O horizon dwelling species form the pioneering population and remove the litter layer. Subsequently, shallow soil mixers are followed by deep burrowing species. As the invasion front advances, O horizons disappear, A horizons become thicker, underlying sandy aeolian blankets are incorporated into the A horizons, and there is an increasingly frequent signs of earthworm burrows in the clay rich Bt horizons. Our preliminary data was from two end members of the chronosequence. Earthworm-driven soil mixing created more vertically homogeneous profiles of elemental compositions. Probably reflecting the upward incorporation of clay and iron-oxide rich Bt horizon materials by earthworms. A horizons in the invaded site were more enriched not only in total Fe and Al but also in crystalline and amorphous forms of iron and aluminum oxides than in the non-invaded soil. Particularly, sodium pyrophosphate extracted pools of Fe and Al, which represent the organically complexed Fe and Al oxides, were significantly greater in the invaded A horizon. This suggests that the iron and aluminum oxides translocated upward by earthworms may help complexing and thus stabilizing organic carbon. Therefore underground invasion of earthworms may significantly intensify the

  3. Trace Metals and Metalloids in Forest Soils and Exotic Earthworms in Northern New England, USA

    PubMed Central

    Richardson, J.B.; Görres, J.H.; Jackson, B.P.; Friedland, A.J.

    2015-01-01

    Trace metals and metalloids (TMM) in forest soils and invasive earthworms were studied at 9 uncontaminated sites in northern New England, USA. Essential (Cu, Mo, Ni, Zn, Se) and toxic (As, Cd, Pb, Hg and U) TMM concentrations (mg kg-1) and pools (mg m-2) were quantified for organic horizons (forest floor), mineral soils and earthworm tissues. Essential TMM tissue concentrations were greatest for mineral soil-feeding earthworm Octolasion cyaneum. Toxic TMM tissue concentrations were highest for organic horizon-feeding earthworms Dendobaena octaedra, Aporrectodea rosea and Amynthas agrestis. Most earthworm species had attained tissue concentrations of Pb, Hg and Se potentially hazardous to predators. Bioaccumulation factors were Cd > Se > Hg > Zn > Pb > U > 1.0 > Cu > As > Mo > Ni. Only Cd, Se Hg and Zn were considered strongly bioaccumulated by earthworms because their average bioaccumulation factors were significantly greater than 1.0. Differences in bioaccumulation did not appear to be caused by soil concentrations as earthworm TMM tissue concentrations were poorly correlated with TMM soil concentrations. Instead, TMM bioaccumulation appears to be species and site dependent. The invasive Amynthas agrestis had the greatest tissue TMM pools, due to its large body mass and high abundance at our stands. We observed that TMM tissue pools in earthworms were comparable or exceeded organic horizon TMM pools; earthworm tissue pools of Cd were up 12 times greater than in the organic horizon. Thus, exotic earthworms may represent an unaccounted portion and flux of TMM in forests of the northeastern US. Our results highlight the importance of earthworms in TMM cycling in northern forests and warrant more research into their impact across the region. PMID:25883392

  4. Invasive and exotic earthworms: an unaccounted change to mercury cycling in northeastern US forest soils

    NASA Astrophysics Data System (ADS)

    Richardson, J. B.; Friedland, A. J.; Görres, J. H.; Renock, D. J.; Jackson, B. P.

    2014-12-01

    Invasive and exotic earthworms are now present in many forested areas of the northeastern US with currently unquantified consequences to abiotic and biotic Hg cycling. To quantify these effects, we measured Hg concentrations (mg kg-1) and amounts (μg m-2) in earthworms and soil horizons at 45 soil pits from 9 sites in northern New England. Seven earthworm species were observed in varying assemblages. Most earthworm species attained concentrations of Hg potentially hazardous to wildlife that may ingest them, with highest concentrations found in shallow-burrowing, litter-feeders. Specifically, Aporrectodea rosea and Amynthas agrestis had the greatest Hg concentrations (0.9 ± 0.1) and Hg amounts (8 ± 2) μg m-2. Aporrectodea rosea and Amynthas agrestis were found to inhabit the forest floor and the top 5 cm of the mineral horizons in high abundance, potentially making it a readily accessible prey species. Bioaccumulation of Hg by invasive and exotic earthworms may be an important mechanism that transfers Hg to ground foraging predators, such as thrushes, red-backed salamanders and foxes, which is generally unaccounted for in terrestrial food chains. Earthworm Hg concentrations were poorly correlated with their respective soil Hg concentrations, suggesting a species dependence for Hg bioaccumulation rather than site effects. We observed that forest floor Hg concentrations and amounts were 23% and 57% lower, respectively, at soil pits with earthworms compared to those without. Moreover, Hg amounts in forest floor-feeding earthworms exceeded the remaining forest floor Hg pools. Mercury concentrations and pools in the mineral soil were 21% and 33% lower, respectively, for soil pits with earthworms compared to those without. We hypothesize that enhanced decomposition, horizon disturbance and bioaccumulation by earthworms has decreased Hg amounts in the forest floor and mineral soil. Our results suggest that earthworms are decreasing Hg storage in forest soils with

  5. Generalization of socially transmitted and instructed avoidance

    PubMed Central

    Cameron, Gemma; Schlund, Michael W.; Dymond, Simon

    2015-01-01

    Excessive avoidance behavior, in which an instrumental action prevents an upcoming aversive event, is a defining feature of anxiety disorders. Left unchecked, both fear and avoidance of potentially threatening stimuli may generalize to perceptually related stimuli and situations. The behavioral consequences of generalization mean that aversive learning experiences with specific threats may lead to the inference that classes of related stimuli are threatening, potentially dangerous, and need to be avoided, despite differences in physical form. Little is known however about avoidance generalization in humans and the learning pathways by which it may be transmitted. In the present study, we compared two pathways to avoidance—instructions and social observation—on subsequent generalization of avoidance behavior, fear expectancy and physiological arousal. Participants first learned that one cue was a danger cue (conditioned stimulus, CS+) and another was a safety cue (CS−). Groups were then either instructed that a simple avoidance response in the presence of the CS+ cancelled upcoming shock (instructed-learning group) or observed a short movie showing a demonstrator performing the avoidance response to prevent shock (observational-learning group). During generalization testing, danger and safety cues were presented along with generalization stimuli that parametrically varied in perceptual similarity to the CS+. Reinstatement of fear and avoidance was also tested. Findings demonstrate, for the first time, generalization of socially transmitted and instructed avoidance: both groups showed comparable generalization gradients in fear expectancy, avoidance behavior and arousal. Return of fear was evident, suggesting that generalized avoidance remains persistent following extinction testing. The utility of the present paradigm for research on avoidance generalization is discussed. PMID:26150773

  6. Managing Earthworm Castings (Oligochaeta: Lumbricidae) in Turfgrass using a Natural By-Product of Tea Oil (Camellia sp.) Manufacture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Earthworm casts are a problem on golf courses and sport fields when they disrupt the playability, aesthetics, and maintenance of playing surfaces. Abundant earthworms alongside airport runways can increase bird strike risk. Currently no pesticides are labeled for earthworms in the United States. W...

  7. Earthworm-produced calcite granules: A new terrestrial palaeothermometer?

    NASA Astrophysics Data System (ADS)

    Versteegh, Emma A. A.; Black, Stuart; Canti, Matthew G.; Hodson, Mark E.

    2013-12-01

    In this paper we show for the first time that calcite granules, produced by the earthworm Lumbricus terrestris, and commonly recorded at sites of archaeological interest, accurately reflect temperature and soil water δ18O values. Earthworms were cultivated in an orthogonal combination of two different (granule-free) soils moistened by three types of mineral water and kept at three temperatures (10, 16 and 20 °C) for an acclimatisation period of three weeks followed by transfer to identical treatments and cultivation for a further four weeks. Earthworm-secreted calcite granules were collected from the second set of soils. δ18O values were determined on individual calcite granules (δ18Oc) and the soil solution (δ18Ow). The δ18Oc values reflect soil solution δ18Ow values and temperature, but are consistently enriched by 1.51 (± 0.12)‰ in comparison to equilibrium in synthetic carbonates. The data fit the equation 1000 ln α = [20.21 ± 0.92] (103 T-1) - [38.58 ± 3.18] (R2 = 0.95; n = 96; p < 0.0005). As the granules are abundant in modern soils, buried soils and archaeological contexts, and can be dated using U-Th disequilibria, the developed palaeotemperature relationship has enormous potential for application to Holocene and Pleistocene time intervals.

  8. Transmission of Nephridial Bacteria of the Earthworm Eisenia fetida

    PubMed Central

    Davidson, Seana K.; Stahl, David A.

    2006-01-01

    The lumbricid earthworms (annelid family Lumbricidae) harbor gram-negative bacteria in their excretory organs, the nephridia. Comparative 16S rRNA gene sequencing of bacteria associated with the nephridia of several earthworm species has shown that each species of worm harbors a distinct bacterial species and that the bacteria from different species form a monophyletic cluster within the genus Acidovorax, suggesting that there is a specific association resulting from radiation from a common bacterial ancestor. Previous microscopy and culture studies revealed the presence of bacteria within the egg capsules and on the surface of embryos but did not demonstrate that the bacteria within the egg capsule were the same bacteria that colonized the nephridia. We present evidence, based on curing experiments, in situ hybridizations with Acidovorax-specific probes, and 16S rRNA gene sequence analysis, that the egg capsules contain high numbers of the bacterial symbiont and that juveniles are colonized during development within the egg capsule. Studies exposing aposymbiotic hatchlings to colonized adults and their bedding material suggested that juvenile earthworms do not readily acquire bacteria from the soil after hatching but must be colonized during development by bacteria deposited in the egg capsule. Whether this is due to the developmental stage of the host or the physiological state of the symbiont remains to be investigated. PMID:16391117

  9. Biological response of earthworm, Eisenia fetida, to five neonicotinoid insecticides.

    PubMed

    Wang, Kai; Pang, Sen; Mu, Xiyan; Qi, Suzhen; Li, Dongzhi; Cui, Feng; Wang, Chengju

    2015-08-01

    Earthworms (Eisenia fetida) are one of the most abundant terrestrial species, and play an important role in maintaining the ecological function of soil. Neonicotinoids are some of the most widely used insecticides applied to crops. Studies on the effect of neonicotinoids on E. fetida are limited. In the present work, we evaluated the effects of five neonicotinoid insecticides on reproduction, cellulase activity and the tissues of E. fetida. The results showed that, the LC50 of imidacloprid, acetamiprid, nitenpyram, clothianidin and thiacloprid was 3.05, 2.69, 4.34, 0.93 and 2.68mgkg(-1), respectively. They also could seriously affect the reproduction of E. fetida, reducing the fecundity by 84.0%, 39.5%, 54.3%, 45.7% and 39.5% at the sub-lethal concentrations of 2.0, 1.5, 0.80, 2.0 and 1.5mgkg(-1), respectively. The cellulase activity of E. fetida was most sensitive to clothianidin. Significant disruption of the epidermal and midgut tissue was observed after 14d exposure. In summary, we demonstrate that imidacloprid, acetamiprid, nitenpyram, clothianidin and thiacloprid have high toxic to earthworm, and can significantly inhibited fecundity and cellulase activity of E. fetida, and they also damage the epidermal and midgut cells of earthworm. PMID:25828917

  10. Determination of pentachlorophenol in wastewater irrigated soils and incubated earthworms.

    PubMed

    Liu, Ying; Wen, Bei; Shan, Xiao-quan

    2006-07-15

    The analyses of low pentachlorophenol (PCP) in soils and earthworms require a sensitive and reliable analytical method. In this paper, several derivatization methods and extraction solvents were compared systematically. The derivatization reagents included acetic anhydride, 2,3,4,5,6-pentafluorobenzyl bromide (PFBBr) and diazomethane. Hexane, acetone, hexane-acetone (1:1), dichloromethane and methanol were used as the extraction solvents. PFBBr derivatization showed the highest sensitivity. The derivatization parameters of PFBBr including the amount of PFBBr, the power and irradiation time of microwave were optimized. As a result, 200 microl of PFBBr (10%) at 150W of microwave oven for 30 min achieved the best result. The PFBBr derivatization method had the detection limit of 0.07 microg l(-1) of PCP. Extraction by a mixture of hexane and acetone (1:1) showed the best recoveries. The recommended method was used to determine the low PCP in soils irrigated by wastewater and earthworms incubated in the corresponding soils. The concentrations of PCP in soils were in the range of 1.38-179 ng g(-1), while those in earthworms were 11.2-262 ng g(-1). The recoveries of the surrogate standard (trichlorophenol) ranged from 81.1% to 107%, demonstrating the merit of the method. PMID:18970711

  11. Modeling of the accumulation of organic lipophilic chemicals in earthworms

    SciTech Connect

    Belfroid, A.; Seinen, W.; Leeuwen, K. van; Hermens, J.; Gestel, K. van

    1994-12-31

    For aquatic and terrestrial species living in contaminated sediments and soils it is assumed that the major route of uptake of organic lipophilic compounds is by passive diffusion of the compound dissolved in the interstitial water. Dietary uptake will only be important for extremely lipophilic compounds with log K{sub ow} larger than 5--6. An accumulation study with earthworms in OECD artificial soil confirmed this hypothesis. However, the authors also observed dietary uptake in earthworms after feeding them with food contaminated with three chlorobenzenes, PCB153 and octachloronaphthalene. Still, the question remained whether dietary uptake is an important route of exposure. Therefore, a model was developed that, unlike for example the equilibrium partition theory, incorporates two routes of uptake. The model can be used to estimate the accumulation of inert organic chemicals with log Kow 2--7 in earthworms, but also to determine the relative contribution of the two routes of uptake to the total body burden. It will be shown that the relative contribution depends on the lipophilicity of the compound and also on the type of soil.

  12. Genotoxicity assessment in Eisenia andrei coelomocytes: a study of the induction of DNA damage and micronuclei in earthworms exposed to B[a]P- and TCDD-spiked soils.

    PubMed

    Sforzini, Susanna; Boeri, Marta; Dagnino, Alessandro; Oliveri, Laura; Bolognesi, Claudia; Viarengo, Aldo

    2012-07-01

    Earthworms are useful indicators of soil quality and are widely used as model organisms in terrestrial ecotoxicology. The assessment of genotoxic effects caused by environmental pollutants is of great concern because of their relevance in carcinogenesis. In this work, the earthworm Eisenia andrei was exposed for 10 and 28 days to artificial standard soil contaminated with environmentally relevant concentrations of benzo[a]pyrene (B[a]P) (0.1, 10, 50ppm) and 2,3,7,8-tetrachloro-dibenzo-para-dioxin (TCDD) (1×10(-5), 1×10(-4), 2×10(-3)ppm). Micronucleus (MNi) induction was evaluated in earthworm coelomocytes after DNA staining with the fluorescent dye DAPI. In the same cells, the DNA damage was assessed by means of the alkaline comet assay. Induction of MNi in coelomocytes, identified according to standard criteria, was demonstrated. B[a]P exposure for 10 and 28 days induced a significant increase in MNi frequency. In TCDD-treated earthworms, a significant effect on chromosomal damage was observed at all the concentrations used; surprisingly, greater effects were induced in animals exposed to the lowest concentration (1×10(-5)ppm). The data of the comet assay revealed a significant increase in the level of DNA damage in coelomocytes of earthworms exposed for 10 and 28 days to the different concentrations of B[a]P and TCDD. The results show that the comet and MN assays were able to reveal genotoxic effects in earthworms exposed even to the lowest concentrations of both chemicals tested here. The combined application in E. andrei of the comet assay and the micronucleus test, which reflect different biological mechanisms, may be suggested to identify genotoxic effects induced in these invertebrates by environmental contaminants in terrestrial ecosystems. PMID:22459015

  13. Reactive Collision Avoidance Algorithm

    NASA Technical Reports Server (NTRS)

    Scharf, Daniel; Acikmese, Behcet; Ploen, Scott; Hadaegh, Fred

    2010-01-01

    The reactive collision avoidance (RCA) algorithm allows a spacecraft to find a fuel-optimal trajectory for avoiding an arbitrary number of colliding spacecraft in real time while accounting for acceleration limits. In addition to spacecraft, the technology can be used for vehicles that can accelerate in any direction, such as helicopters and submersibles. In contrast to existing, passive algorithms that simultaneously design trajectories for a cluster of vehicles working to achieve a common goal, RCA is implemented onboard spacecraft only when an imminent collision is detected, and then plans a collision avoidance maneuver for only that host vehicle, thus preventing a collision in an off-nominal situation for which passive algorithms cannot. An example scenario for such a situation might be when a spacecraft in the cluster is approaching another one, but enters safe mode and begins to drift. Functionally, the RCA detects colliding spacecraft, plans an evasion trajectory by solving the Evasion Trajectory Problem (ETP), and then recovers after the collision is avoided. A direct optimization approach was used to develop the algorithm so it can run in real time. In this innovation, a parameterized class of avoidance trajectories is specified, and then the optimal trajectory is found by searching over the parameters. The class of trajectories is selected as bang-off-bang as motivated by optimal control theory. That is, an avoiding spacecraft first applies full acceleration in a constant direction, then coasts, and finally applies full acceleration to stop. The parameter optimization problem can be solved offline and stored as a look-up table of values. Using a look-up table allows the algorithm to run in real time. Given a colliding spacecraft, the properties of the collision geometry serve as indices of the look-up table that gives the optimal trajectory. For multiple colliding spacecraft, the set of trajectories that avoid all spacecraft is rapidly searched on

  14. The lateral septum and anterior hypothalamus act in tandem to regulate burying in the shock-probe test but not open-arm avoidance in the elevated plus-maze.

    PubMed

    Lamontagne, Steven J; Olmstead, Mary C; Menard, Janet L

    2016-11-01

    Both the lateral septum (LS) and anterior hypothalamus (AHA) regulate behavioural defense. We tested whether those two interconnected structures act in serial in that regard. Infusions of the GABAA agonist muscimol into one side of the LS and the contralateral (but not ipsilateral) AHA suppressed rats' burying in the shock-probe test whereas none of our muscimol infusion approaches altered their open-arm avoidance in the elevated plus-maze. These results suggest that the LS-AHA circuit serves a specialized role in defensive responses towards discrete, localizable threat stimuli but not towards potential threats. PMID:27485402

  15. Earthworms enhance soil health and may also assist in improving biological insect pest suppression in pecans

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prior research indicated that earthworms may serve as phoretic hosts to entomopathogenic nematodes. Therefore, we hypothesized that biocontrol efficacy of entomopathogenic nematodes could be enhanced in the presence of earthworms based on increased nematode dispersal through the soil. We also hypo...

  16. Earthworms, Microbes and the Release of C and N in Biochar Amended Soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Land application of biochar has the potential to increase soil fertility and sequester carbon. It is unclear how soil microbes and earthworms interact with biochar and affect release or retention of nutrients. In order to determine the effects and interactions among soil microbes, earthworms, and bi...

  17. Portable Conduction Velocity Experiments Using Earthworms for the College and High School Neuroscience Teaching Laboratory

    ERIC Educational Resources Information Center

    Shannon, Kyle M.; Gage, Gregory J.; Jankovic, Aleksandra; Wilson, W. Jeffrey; Marzullo, Timothy C.

    2014-01-01

    The earthworm is ideal for studying action potential conduction velocity in a classroom setting, as its simple linear anatomy allows easy axon length measurements and the worm's sparse coding allows single action potentials to be easily identified. The earthworm has two giant fiber systems (lateral and medial) with different conduction…

  18. Earthworms as phoretic hosts for Steinernema carpocapsae and Beauveria bassiana: Implications for enhanced biological control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prior research indicated that earthworms may serve as phoretic hosts to entomopathogenic nematodes. Therefore, we hypothesized that biocontrol efficacy of nematodes could be enhanced in the presence of earthworms based on increased nematode dispersal through the soil. We also hypothesized that ear...

  19. Mutualism between common earthworm (Lumbricus terrestris) and giant ragweed (Ambrosia trifida) varies between Ohio and Illinois

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seed caching of giant ragweed by common earthworm has been found to contribute to giant ragweed recruitment success in Ohio (OH) by protecting the seeds from postdispersal predation at a depth in the earthworm midden that is also suitable for germination. The objective of this study was to quantify ...

  20. Earthworms as vectors of Escherichia coli O157:H7 in soil and vermicomposts.

    PubMed

    Williams, A Prysor; Roberts, Paula; Avery, Lisa M; Killham, Ken; Jones, David L

    2006-10-01

    Survival and movement of Escherichia coli O157:H7 in both soil and vermicompost is of concern with regards to human health. Whilst it is accepted that E. coli O157:H7 can persist for considerable periods in soils, it is not expected to survive thermophilic composting processes. However, the natural behavior of earthworms is increasingly utilized for composting (vermicomposting), and the extent to which earthworms promote the survival and dispersal of the bacterium within such systems is unknown. The faecal material produced by earthworms provides a ready supply of labile organic substrates to surrounding microbes within soil and compost, thus promoting microbial activity. Earthworms can also cause significant movement of organisms through the channels they form. Survival and dispersal of E. coli O157:H7 were monitored in contaminated soil and farmyard manure subjected to earthworm digestion over 21 days. Our findings lead to the conclusion that anecic earthworms such as Lumbricus terrestris may significantly aid vertical movement of E. coli O157 in soil, whereas epigeic earthworms such as Dendrobaena veneta significantly aid lateral movement within compost. Although the presence of earthworms in soil and compost may aid proliferation of E. coli O157 in early stages of contamination, long-term persistence of the pathogen appears to be unaffected. PMID:16958908

  1. Exotic earthworm effects on hardwood forest floor, nutrient availability and native plants: a mesocosm study.

    PubMed

    Hale, Cindy M; Frelich, Lee E; Reich, Peter B; Pastor, John

    2008-03-01

    A greenhouse mesocosm experiment, representing earthworm-free North American Acer-dominated forest floor and soil conditions, was used to examine the individual and combined effects of initial invasion by three European earthworm species (Dendrobaena octaedra, Lumbricus rubellus and Lumbricus terrestris) on the forest floor and upper soil horizons, N and P availability, and the mortality and biomass of four native understory plant species (Acer saccharum, Aquilegia canadensis, Aralia racemosa, and Carex pensylvanica). All the three earthworm species combined caused larger impacts on most variables measured than any single earthworm species. These included loss of O horizon mass, decreased thickness of the O horizon and increased thickness of the A horizon, and higher availability of N and P. The latter finding differs from field reports where nutrients were less available after invasion, and probably represents an initial transient increase in nutrient supply as earthworms consume and incorporate the O horizon into the A horizon. Earthworms also increased mortality of plants and decreased total mesocosm plant biomass, but here the impact of all the three earthworm species was no greater than that of L. terrestris and/or L. rubellus alone. This study corroborates field studies that European earthworm invasions alter North American forest ecosystem processes by initiating a cascade of impacts on plant community composition and soil properties. PMID:18066602

  2. Interactions of earthworms with Atrazine-degrading bacteria in an agricultural soil.

    PubMed

    Kersanté, Anne; Martin-Laurent, Fabrice; Soulas, Guy; Binet, Françoise

    2006-08-01

    In the last 10 years, accelerated mineralization of Atrazine (2-chloro-ethylamino-6-isopropylamino-s-triazine) has been evidenced in agricultural soils repeatedly treated with this herbicide. Here, we report on the interaction between earthworms, considered as soil engineers, and the Atrazine-degrading community. The impact of earthworm macrofauna on Atrazine mineralization was assessed in representative soil microsites of earthworm activities (gut contents, casts, burrow linings). Soil with or without earthworms, namely the anecic species Lumbricus terrestris and the endogenic species Aporrectodea caliginosa, was either inoculated or not inoculated with Pseudomonas sp. ADP, an Atrazine-degrading strain, and was either treated or not treated with Atrazine. The structure of the bacterial community, the Atrazine-degrading activity and the abundance of atzA, B and C sequences in soil microsites were investigated. Atrazine mineralization was found to be reduced in representative soil microsites of earthworm activities. Earthworms significantly affected the structure of soil bacterial communities. They also reduced the size of the inoculated population of Pseudomonas sp. ADP, thereby contributing to the diminution of the Atrazine-degrading genetic potential in representative soil microsites of earthworm activities. This study illustrates the regulation produced by the earthworms on functional bacterial communities involved in the fate of organic pollutants in soils. PMID:16867138

  3. Effects of heavy metals on earthworms along contamination gradients in organic rich soils.

    PubMed

    Lukkari, Tuomas; Taavitsainen, Mirka; Väisänen, Ari; Haimi, Jari

    2004-11-01

    Earthworm communities and metal (bio)availability to earthworms along contamination gradients was studied in order to support chemical analyses in risk assessment of metal contaminated soils. Earthworms were sampled in three metal contaminated areas with different habitat and soil properties in Finland. Earthworm and soil samples were collected at three distances (1, 2, and 4 km) from the emission sources. Earthworms were identified as to species and analyzed for heavy metals. Total soil metal concentrations were analyzed using an ultrasound-assisted extraction method and bioavailable metal fraction was estimated by acetic acid extraction. In two of the three areas studied, heavy metal concentrations close to the emission sources were high enough to have harmful effects on earthworms and their environments. In general, diversity, total numbers, and biomass of earthworms increased with increasing distance from the emission sources. When individuals were available for analyses close to the emission source, positive correlations between metal concentrations in the earthworms and those in the soils were observed. PMID:15388274

  4. Phagocytosis in earthworms: An environmentally acceptable endpoint to assess immunotoxic potential of contaminated soils

    SciTech Connect

    Giggleman, M.A.; Fitzpatrick, L.C.; Goven, A.J.; Venables, B.J.; Callahan, C.A.

    1995-12-31

    Phagocytosis, a host-defense mechanism phylogenetically conserved throughout the animal kingdom, by earthworm (Lumbricus terrestris) coelomocytes has potential as a surrogate for vertebrates to be used as an environmentally acceptable endpoint to assess sublethal immunotoxic risks of contaminated soils to environmental (eg. higher wildlife) and public health. Coelomocytes can be exposed in vivo to complex contaminated parent soils by placing earthworms in situ at hazardous waste sites (HWS) or into soil samples and their dilutions with artificial soil (AS) in the laboratory, or in vitro to soil extracts and their fractionations. Here the authors report on phagocytosis by coelomocytes in earthworms exposed to pentachlorophenol (PCP) contaminated soils from a wood treatment HWS, PCP-spiked AS and PCP treated filter paper (FP). HWS soil was diluted to 25% with AS to a sublethal concentration (ca. 125 mg kg{sup {minus}1}) and earthworms exposed for 14d at 10 C under light conditions. AS was spiked at ca. 125 mg kg{sup {minus}1} PCP and earthworms were similarly exposed. Controls for both consisted of earthworms exposed to 100% AS. Earthworms were exposed to FP treated with a sublethal PCP concentration (15 {micro}g cm{sup {minus}2}) at 10 C under dark conditions for 96H. Controls were similarly exposed without PCP. Phagocytosis by coelomocytes in earthworms exposed to HWS soil, spiked AS and treated FP was suppressed 37, 41 and 29%, respectively. Results are discussed in terms of PCP body burdens and exposure protocols.

  5. Effects of treatment with sodium fluoride and subsequent starvation on fluoride content of earthworms

    SciTech Connect

    Walton, K.C.

    1987-01-01

    The two experiments described here originated during a long-term investigation into the occurrence and movement of pollutant fluoride in a terrestrial ecosystem. Moles (Talpa europaea) whose diet consist largely of various species of earthworm Lumbricidae, are one of the species under investigation. Bone fluoride in moles was found to be higher, on average, than in foxes or small rodents. Moles probably acquire fluoride from their earthworm diet. Earthworms do not have any readily identifiable tissue in which to store large amounts of fluoride but, for their size, they have a considerable amount of soil in their gut, up oto 20% of their dry weight. Preliminary measurements of fluoride in whole earthworms suggested that observed levels could probably be accounted for by fluoride bound in the mineral part of contained soil and released during preparatory ashing. Two experiments to investigate this situation are described; here their aims were: to expose earthworms kept in soil to different concentrations of sodium fluoride; to measure resulting fluoride in earthworms when soil was removed from their gut by starvation for varying periods of time; and to compare amounts of fluoride in whole starved earthworms with those in starved earthworms from which remaining soil had also been physically removed by dissection and washing.

  6. Molecular tools to understand the bioremediation effect of plants and earthworms on contaminated marine sediments.

    PubMed

    Moreno, Beatriz; Cañizares, Rosa; Macci, Cristina; Doni, Serena; Masciandaro, Grazia; Benitez, Emilio

    2015-12-30

    A meso-scale pilot plant was set up to test the efficiency of a bioremediation scheme applied to marine sediments contaminated by heavy metals and hydrocarbons. The experiment was implemented for three years in two stages using two remediation agents: plants (Paspalum vaginatum and Tamarix gallica) and earthworms (Eisenia fetida). DNA and RNA-based methodologies were applied to elucidate the dynamics of the bacterial population and were related to improving biological and chemical conditions of the sediments. Bioremediation strategies were successful in removing pollutants from the contaminated sediments and specialization within the bacterial community related to the type of contamination present was detected in the different stages of the process. The highest response of Gram-positive PAH-degraders to the contamination was detected at the beginning and after the first stage of the experiment, corresponding to the uppermost values of degradation. PMID:26223013

  7. Capacitor Test, Evaluation. and Modeling Within NASA Electronic Parts and Packaging (NEPP) Program. "Why Ceramic Capacitors Fracture During Manual Soldering and How to Avoid Failures"

    NASA Technical Reports Server (NTRS)

    Teverovsky, Alexander

    2011-01-01

    Presentation discusses: (1) Why Multi-Layer Ceramic Capacitors(MLCCs) crack during manual soldering? Workmanship and parts issues. (2) Do existing qualification requirements assure crack-free soldering? MIL-spec Thermal Shock (TS) testing. MIL-spec Resistance to Soldering Heat (RSH) test. (3) What test can assure reliable soldering? Mechanical characteristics of ceramics. Comparison of three TS techniques: LND, TSD, and IWT. (4) Simulation of TS conditions.

  8. Assessing the fate and effects of nano aluminum oxide in the terrestrial earthworm, Eisenia fetida.

    PubMed

    Coleman, Jessica G; Johnson, David R; Stanley, Jacob K; Bednar, Anthony J; Weiss, Charles A; Boyd, Robert E; Steevens, Jeffery A

    2010-07-01

    Nano-sized aluminum is currently being used by the military and commercial industries in many applications including coatings, thermites, and propellants. Due to the potential for wide dispersal in soil systems, we chose to investigate the fate and effects of nano-sized aluminum oxide (Al2O3), the oxidized form of nano aluminum, in a terrestrial organism. The toxicity and bioaccumulation potential of micron-sized (50-200 microm, nominal) and nano-sized (11 nm, nominal) Al2O3 was comparatively assessed through acute and subchronic bioassays using the terrestrial earthworm, Eisenia fetida. Subchronic (28-d) studies were performed exposing E. fetida to nano- and micron-sized Al2O3-spiked soils to assess the effects of long-term exposure. No mortality occurred in subchronic exposures, although reproduction decreased at >or=3,000 mg/kg nano-sized Al2O3 treatments, with higher aluminum body burdens observed at 100 and 300 mg/kg; no reproductive effects were observed in the micron-sized Al2O3 treatments. In addition to toxicity and bioaccumulation bioassays, an acute (48-h) behavioral bioassay was conducted utilizing a soil avoidance wheel in which E. fetida were given a choice of habitat between control, nano-, or micron-sized Al2O3 amended soils. In the soil avoidance bioassays, E. fetida exhibited avoidance behavior toward the highest concentrations of micron- and nano-sized Al2O3 (>5,000 mg/kg) relative to control soils. Results of the present study indicate that nano-sized Al2O3 may impact reproduction and behavior of E. fetida, although at high levels unlikely to be found in the environment. PMID:20821608

  9. Earthworms modify microbial community structure and accelerate maize stover decomposition during vermicomposting.

    PubMed

    Chen, Yuxiang; Zhang, Yufen; Zhang, Quanguo; Xu, Lixin; Li, Ran; Luo, Xiaopei; Zhang, Xin; Tong, Jin

    2015-11-01

    In the present study, maize stover was vermicomposted with the epigeic earthworm Eisenia fetida. The results showed that, during vermicomposting process, the earthworms promoted decomposition of maize stover. Analysis of microbial communities of the vermicompost by high-throughput pyrosequencing showed more complex bacterial community structure in the substrate treated by the earthworms than that in the control group. The dominant microbial genera in the treatment with the earthworms were Pseudoxanthomonas, Pseudomonas, Arthrobacter, Streptomyces, Cryptococcus, Guehomyces, and Mucor. Compared to the control group, the relative abundance of lignocellulose degradation microorganisms increased. The results indicated that the earthworms modified the structure of microbial communities during vermicomposting process, activated the growth of lignocellulose degradation microorganisms, and triggered the lignocellulose decomposition. PMID:26139410

  10. Fluoride accumulation in different earthworm species near an industrial emission source in southern Germany

    SciTech Connect

    Vogel, J.; Ottow, J.C.G. )

    1991-10-01

    The information on fluorides (F)-pollution of soil invertebrates is sparse and only a few recent publications deal with F accumulation in some taxonomic groups of soil fauna. Earthworms in particular become the focus of soil-soil fauna interactions in F-polluted sites, even more so since a significant relationship between soil pollution and F load in earthworms was observed. Earthworms coat their burrowings and this may be a mechanism of F-dissemination and subsoil contamination. Evidence is growing that fluorides pass through food chains. Earthworms as the preferred prey of a wide range of animals are therefore in the center of interest as a possible way of F-bioaccumulation in higher trophic levels. For a risk assessment of F-pollution and pathways of F through organisms and ecosystems, detailed knowledge of F-accumulation in soil fauna, and in earthworms in particular is required.

  11. Reduced greenhouse gas mitigation potential of no-tillage soils through earthworm activity.

    PubMed

    Lubbers, Ingrid M; van Groenigen, Kees Jan; Brussaard, Lijbert; van Groenigen, Jan Willem

    2015-01-01

    Concerns about rising greenhouse gas (GHG) concentrations have spurred the promotion of no-tillage practices as a means to stimulate carbon storage and reduce CO2 emissions in agro-ecosystems. Recent research has ignited debate about the effect of earthworms on the GHG balance of soil. It is unclear how earthworms interact with soil management practices, making long-term predictions on their effect in agro-ecosystems problematic. Here we show, in a unique two-year experiment, that earthworm presence increases the combined cumulative emissions of CO2 and N2O from a simulated no-tillage (NT) system to the same level as a simulated conventional tillage (CT) system. We found no evidence for increased soil C storage in the presence of earthworms. Because NT agriculture stimulates earthworm presence, our results identify a possible biological pathway for the limited potential of no-tillage soils with respect to GHG mitigation. PMID:26337488

  12. Reduced greenhouse gas mitigation potential of no-tillage soils through earthworm activity

    PubMed Central

    Lubbers, Ingrid M.; Jan van Groenigen, Kees; Brussaard, Lijbert; van Groenigen, Jan Willem

    2015-01-01

    Concerns about rising greenhouse gas (GHG) concentrations have spurred the promotion of no-tillage practices as a means to stimulate carbon storage and reduce CO2 emissions in agro-ecosystems. Recent research has ignited debate about the effect of earthworms on the GHG balance of soil. It is unclear how earthworms interact with soil management practices, making long-term predictions on their effect in agro-ecosystems problematic. Here we show, in a unique two-year experiment, that earthworm presence increases the combined cumulative emissions of CO2 and N2O from a simulated no-tillage (NT) system to the same level as a simulated conventional tillage (CT) system. We found no evidence for increased soil C storage in the presence of earthworms. Because NT agriculture stimulates earthworm presence, our results identify a possible biological pathway for the limited potential of no-tillage soils with respect to GHG mitigation. PMID:26337488

  13. Accumulation of mercury and methylmercury by mushrooms and earthworms from forest soils.

    PubMed

    Rieder, Stephan R; Brunner, Ivano; Horvat, Milena; Jacobs, Anna; Frey, Beat

    2011-10-01

    Accumulation of total and methyl-Hg by mushrooms and earthworms was studied in thirty-four natural forest soils strongly varying in soil physico-chemical characteristics. Tissue Hg concentrations of both receptors did hardly correlate with Hg concentrations in soil. Both total and methyl-Hg concentrations in tissues were species-specific and dependent on the ecological groups of receptor. Methyl-Hg was low accounting for less than 5 and 8% of total Hg in tissues of mushrooms and earthworms, respectively, but with four times higher concentrations in earthworms than mushrooms. Total Hg concentrations in mushrooms averaged 0.96 mg Hg kg(-1) dw whereas litter decomposing mushrooms showed highest total Hg and methyl-Hg concentrations. Earthworms contained similar Hg concentrations (1.04 mg Hg kg(-1) dw) whereas endogeic earthworms accumulated highest amounts of Hg and methyl-Hg. PMID:21621314

  14. Metal content of earthworms in sludge-amended soils: uptake and loss

    SciTech Connect

    Neuhauser, E.F.; Malecki, M.R.; Cukic, Z.V.

    1985-11-01

    The widespread practice of landspreading of sludge has raised concern about increasing concentrations of potentially toxic metals in soils, with the possibility of these metals adversely impacting terrestrial and aquatic ecosystems. Earthworms, as one of the largest components of the soil biota, are useful indicators of potentially toxic soil metal concentrations. The study describes the metal content of five metals (Cd, Cu, Ni, Pb, and Zn) in one earthworm species, Allolobophora tuberculata, as a function of varying soil metal concentrations in the same soil type and the ability of the earthworms to bioconcentrate the five metals. The rate of uptake of the five metals in earthworms with initially low concentrations of metals placed in a soil with high metal concentrations was evaluated for a 112 day period. The rate of loss of the five metals in earthworms with initially high metal concentrations placed in soil with low metal concentrations was also examined.

  15. Individual and combined toxic effects of herbicide atrazine and three insecticides on the earthworm, Eisenia fetida.

    PubMed

    Wang, Yanhua; An, Xuehua; Shen, Weifeng; Chen, Liezhong; Jiang, Jinhua; Wang, Qiang; Cai, Leiming

    2016-07-01

    In the present study, we evaluated the individual and combined toxic effects of herbicide atrazine and three insecticides (chlorpyrifos, lambda-cyhalothrin and imidacloprid) on the earthworm, Eisenia fetida. Results from 48-h filter paper test indicated that imidacloprid had the highest toxicity to E. fetida with an LC50 of 0.05 (0.041-0.058) μg a.i. cm(-2), followed by lambda-cyhalothrin and atrazine with LC50 values ranging from 4.89 (3.52-6.38) to 4.93 (3.76-6.35) μg a.i. cm(-2), while chlorpyrifos had the least toxicity to the worms with an LC50 of 31.18 (16.22-52.85) μg a.i. cm(-2). Results from 14-days soil toxicity test showed a different pattern of toxicity except that imidacloprid was the most toxic even under the soil toxicity bioassay system. The acute toxicity of atrazine was significantly higher than that of chlorpyrifos. In contrast, lambda-cyhalothrin was the least toxic to the animals under the soil toxicity bioassay system. The binary mixture of atrazine-lambda-cyhalothrin and ternary mixture of atrazine-chlorpyrifos-lambda-cyhalothrin displayed a significant synergistic effect on the earthworms under the soil toxicity bioassay. Our findings would help regulatory authorities understand the complexity of effects from pesticide mixtures on non-target organisms and provide useful information of the interaction of various pesticide classes detected in natural environment. PMID:27068296

  16. Avoiding Sophomore Jinx.

    ERIC Educational Resources Information Center

    Fitzpatrick, James

    2002-01-01

    After the first year, new superintendents should take care to avoid the "sophomore jinx" by communicating effectively with the board president every week and with board members before meetings. Public engagement is also an integral part of a superintendent's job. (MLF)

  17. Pitcherpot: Avoiding Honeypot Detection

    NASA Astrophysics Data System (ADS)

    Panchal, Vinod K.; Bhatnagar, Pramod K.; Bhatnagar, Mitul

    This paper explores the various ways honeypots could be detected by the malicious attacker. This includes the different prevalent criteria and characteristics for honeypots generation & their weaknesses. Further this paper proposes a new way of implementation of a honeypot (Pitcher pots Systems) that effectively facilitate its identity avoidance and yet offers better ways to study the attacker.

  18. Myelin Avoids the JAM.

    PubMed

    Follis, Rose M; Carter, Bruce D

    2016-08-17

    In this issue of Neuron, Redmond et al. (2016) identify junction adhesion molecule 2 (JAM2) as an inhibitor of somatodendritic myelination in spinal cord neurons, thereby elucidating how myelin forms on axons but avoids dendrites and cell bodies. PMID:27537479

  19. Avoiding the "M" Word.

    ERIC Educational Resources Information Center

    Klinger, Donna

    2001-01-01

    Provides an overview of roundtable discussions by top business officers about how higher education can capitalize on strategic alliances. Describes how, by working with one another and with corporate partners, colleges and universities can avoid closing their doors or merging with stronger institutions. (EV)

  20. Plants to Avoid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Knowledge of poisonous plants is extremely important for home owners, gardeners, farmers, hunters, hikers, and the rest of the general public. Among the most important plants to avoid in the Delta Region are poison ivy, bull nettle, eastern black nightshade, Queen Ann’s lace, jimsonweed, and trumpe...

  1. Psychological Treatments to Avoid

    ERIC Educational Resources Information Center

    Thomason, Timothy C.

    2010-01-01

    Certain psychological treatments should be avoided, and a list of such treatments would provide valuable guidance for counselors, as well as potential clients. It is well established that some therapies are potentially dangerous, and some fringe therapies are highly unlikely to help clients beyond a placebo effect. This article provides an…

  2. Non-native earthworms in riparian soils increase nitrogen flux into adjacent aquatic ecosystems.

    PubMed

    Costello, David M; Lamberti, Gary A

    2008-12-01

    Riparian zones are an important transition between terrestrial and aquatic ecosystems, and they function in nutrient cycling and removal. Non-native earthworms invading earthworm-free areas of North America can affect nutrient cycling in upland soils and have the potential to affect it in riparian soils. We examined how the presence of earthworms can affect riparian nutrient cycling and nutrient delivery to streams. Two mesocosm experiments were conducted to determine how (1) the biomass of earthworms and (2) earthworm species can affect nutrient flux from riparian zones to nearby streams and how this flux can affect streamwater nutrients and periphyton growth. In separate experiments, riparian soil cores were amended with one of four mixed earthworm biomasses (0, 4, 10, or 23 g m(-2) ash-free dry mass) or with one of three earthworm species (Aporrectodea caliginosa, Lumbricus terrestris, L. rubellus) or no earthworm species. Riparian soil cores were coupled to artificial streams, and over a 36-day period, we measured nutrient leaching rates, in-stream nutrient concentrations, and periphyton growth. Ammonium leaching increased with increasing biomass and was greatest from the A. caliginosa treatments. Nitrate leaching increased through time and increased at a greater rate with higher biomass and from cores containing A. caliginosa. We suggest that the overall response of increased nitrate leaching [90% of total nitrogen (N)] was due to a combination of ammonium excretion and burrowing by earthworms, which increased nitrification rates. During both experiments, periphyton biomass increased through time but did not differ across treatments despite high in-stream inorganic N. Through time, in-stream phosphorus (P) concentration declined to <5 microg l(-1), and periphyton growth was likely P-limited. We conclude that activities of non-native earthworms (particularly A. caliginosa) can alter biogeochemical cycling in riparian zones, potentially reducing the N

  3. A field screening method using earthworms (Eisenia foetida andrei) to evaluate contaminated soils

    SciTech Connect

    Wilborn, D.C.; Bollman, M.A.; Gillett, C.S.; Ott, S.L.; Linder, G.L.

    1997-09-01

    An on-site biological assessment for soil toxicity was performed using a lumbricid earthworm, Eisenia foetida andrei, at the Milltown Reservoir Superfund Site on the Clark Fork River near Missoula, MT. The assessment provided an opportunity to evaluate test containers and methodologies. Sixty-four field test stations, each consisting of three test containers of site soil, a control container of artificial soil, and a container to house soil moisture and temperature recording devices, were used. Laboratory tests were conducted on soil samples from selected field stations. The test containers were constructed from sections of polyvinyl chloride pipe and were found to be suitable in preventing escape of test organisms and damage by animals. The site soils had levels of arsenic, lead, cadmium, copper, and zinc higher than those in surrounding watersheds. Combined mortality for exposure to the site soil was similar in both the laboratory and field tests. Combined sublethal responses to the site soil were also similar in both laboratory and field tests. Artificial soil controls in both field and laboratory tests resulted in combined mortality rates of 1% or less. The methodologies employed proved successful in maintaining an adequate soil moisture level and allowed for measurement of soil temperature.

  4. Earthworm survival and behavior results from a Clark Fork River Superfund site: Grant-Kohrs Ranch N.H.S., Montana

    SciTech Connect

    Rader, B.R.; Nimmo, D.R.; Chapman, P.L.

    1995-12-31

    Concentrations of heavy metals in sediments and soils deposited along the floodplain of the Clark Fork River, within the boundaries of the Grant-Kohrs Ranch National Historic Site, have exceeded those typically found in uncontaminated soils. Upstream mining activities along the Clark Fork River in the Deer Lodge Valley, Montana, have produced substantial quantities of mine waste which have been deposited throughout the watershed. Releases and re-releases of these contaminated substances continue to occur, and appear to be preventing the germination and establishment of critical riparian plant species and depressing soil microbe activity. Slickens, bare spots devoid of all vegetation, occur frequently in the floodplain along the Clark Fork River. This research investigates the toxicity of slicken soils using a series of earthworm (Eisenia foetida andrei) survival and behavior tests. In dilution tests, earthworm survival was reduced significantly in as little as 12.5% slicken soil. Results from earthworm behavior tests currently being conducted using non-lethal slicken soil dilutions will also be presented.

  5. Potential impacts of invasive European earthworms and soil moisture on herbaceous species richness within the Ojibwa Red Lake Reservation

    NASA Astrophysics Data System (ADS)

    Thayer, C.; Top, S. M.; Filley, T. R.; Jourdain, J.; Zurn-Birkhimer, S.; Kroeger, T.; Welle, P.; Jenkins, M.; Johnson, A.; Gemscholars

    2010-12-01

    Throughout many northern North American forests invasive earthworms have caused significant ecological alteration to soil structure and chemistry, fine root distributions, duff and litter layer thickness, and soil moisture. Additionally, this phenomenon has been implicated in shifts in herbaceous-layer vegetation. Over the past 4 years, we have established research plots in forests on the Ojibwa Red Lake Reservation (Minnesota) to study the impact of exotic earthworms on forest ecosystem structure and functions. To examine herbaceous-layer response to potential gradients in earthworm abundance and soil moisture, we conducted surveys of herbaceous-layer species cover, earthworm abundance, and soil moisture across six plot dispersed along a previously identified gradient of earthworm activity. Our initial results have shown that the earthworms abundance is positively related to soil moisture (R2 = 0.76, P = 0.023). Herbaceous species richness displayed a strong negative relationship to soil moisture (R2 = 0.91, P < 0.001) and a weak negative relationship to earthworm abundance (R2 =0.51, P = 0.113). On average, the number of earthworms is increasing and the sites with more earthworms typically have less leaf litter. Additional work is needed to determine if earthworms are influencing site moisture conditions, or if moisture availability is a driver of earthworm abundance.

  6. Integration of Weather Avoidance and Traffic Separation

    NASA Technical Reports Server (NTRS)

    Consiglio, Maria C.; Chamberlain, James P.; Wilson, Sara R.

    2011-01-01

    This paper describes a dynamic convective weather avoidance concept that compensates for weather motion uncertainties; the integration of this weather avoidance concept into a prototype 4-D trajectory-based Airborne Separation Assurance System (ASAS) application; and test results from a batch (non-piloted) simulation of the integrated application with high traffic densities and a dynamic convective weather model. The weather model can simulate a number of pseudo-random hazardous weather patterns, such as slow- or fast-moving cells and opening or closing weather gaps, and also allows for modeling of onboard weather radar limitations in range and azimuth. The weather avoidance concept employs nested "core" and "avoid" polygons around convective weather cells, and the simulations assess the effectiveness of various avoid polygon sizes in the presence of different weather patterns, using traffic scenarios representing approximately two times the current traffic density in en-route airspace. Results from the simulation experiment show that the weather avoidance concept is effective over a wide range of weather patterns and cell speeds. Avoid polygons that are only 2-3 miles larger than their core polygons are sufficient to account for weather uncertainties in almost all cases, and traffic separation performance does not appear to degrade with the addition of weather polygon avoidance. Additional "lessons learned" from the batch simulation study are discussed in the paper, along with insights for improving the weather avoidance concept. Introduction

  7. Effects of spatial and temporal variation in metal availability on earthworms in floodplain soils of the river Dommel, The Netherlands.

    PubMed

    Bleeker, Eric A J; van Gestel, Cornelis A M

    2007-08-01

    Regarding impact on ecological soil functioning, metal pollution is often considered a constant factor for certain sampling sites. However, especially bioavailable concentrations may differ in space and time. This aspect was investigated on four sites along a metal-polluted river, differing in soil characteristics and metal concentrations. Every four weeks earthworm densities, soil characteristics, and metal concentrations in soil and earthworms were determined. Earthworm biomass and density fluctuated in time and increased with increasing metal contamination, indicating the presence of compensating factors. Multivariate analysis suggested organic matter and moisture content to be the main factors explaining earthworm biomass. Metal concentrations in the earthworms increased with increasing total or 0.01M CaCl(2) extractable soil concentrations, but no time-related trends were seen. Cadmium concentrations in the earthworms exceeded background values, suggesting a potential risk. The neutral red retention biomarker assay, however, did not show any signs of metal stress in the earthworms. PMID:17376569

  8. Determination of MBT-waste reactivity - An infrared spectroscopic and multivariate statistical approach to identify and avoid failures of biological tests.

    PubMed

    Böhm, K; Smidt, E; Binner, E; Schwanninger, M; Tintner, J; Lechner, P

    2010-04-01

    The Austrian Landfill Ordinance provides limit values regarding the reactivity for the disposal of mechanically biologically treated (MBT) waste before landfilling. The potential reactivity determined by biological tests according to the Austrian Standards (OENORM S 2027 1-2) can be underestimated if the microbial community is affected by environmental conditions. New analytical tools have been developed as an alternative to error-prone and time-consuming biological tests. Fourier Transform Infrared (FT-IR) spectroscopy in association with Partial Least Squares Regression (PLS-R) was used to predict the reactivity parameters respiration activity (RA(4)) and gas generation sum (GS(21)) as well as to detect errors resulting from inhibiting effects on biological tests. For this purpose 250 MBT-waste samples from different Austrian MBT-plants were investigated using FT-IR spectroscopy in the mid (MIR) and near infrared (NIR) area and biological tests. Spectroscopic results were compared with those from biological tests. Arising problems caused by interferences of RA(4) and GS(21) are discussed. It is shown that FT-IR spectroscopy predicts RA(4) and GS(21) reliably to assess stability of MBT-waste materials and to detect errors. PMID:19854633

  9. Aggregate formation and soil carbon sequestration by earthworms at the ORNL FACE experiment

    NASA Astrophysics Data System (ADS)

    Sanchez-de Leon, Y.; Gonzalez-Meler, M. A.; Lugo-Perez, J.; Wise, D. H.; Jastrow, J. D.

    2012-12-01

    Earthworms have an important role in soil carbon sequestration, but their contribution to carbon sequestration in soils exposed to elevated atmospheric CO2 concentrations has been largely overlooked. Previous studies at the Oak Ridge National Laboratory Free Air CO2 Experiment (ORNL FACE) site showed that the formation of soil aggregates is a key mechanism for soil carbon sequestration. We did a microcosm experiment to quantify earthworm-mediated aggregate formation and compare between two earthworm species with different feeding habits (endogeic vs. epi-edogeic). In addition, we wanted to identify the carbon source (soil, leaf litter or root litter) within aggregates formed by earthworms. We used 13C-depleted soil and 15N-enriched sweetgum (Liquidambar styraciflua) leaf and root litter collected from the ORNL FACE site to assess soil aggregate formation of the native, endogeic earthworm Diplocardia sp. and European, epi-endogeic earthworm Lumbricus rubellus. Both earthworm species are present at the ORNL FACE site. We crushed, sieved (< 250 μm) soil and prepared four treatments: (I) soil only; (II) soil and plant material; (III) soil, plant material and Diplocardia sp.; (IV) soil, plant material and L. rubellus. All treatments were at 30% water content and temperature was maintained at 20°C. The incubation period lasted 26 days. We measured aggregate size distribution, total aggregate carbon content and 13C and 15N to elucidate aggregate carbon source. Newly formed soil macroaggregates (> 250 μm) were higher in treatments with earthworms (III and IV) than in treatments without earthworms (I and II) (p = 0.02). Within macroaggregates, most of the carbon was soil-derived. Leaf and root-derived carbon was found in treatment IV only. Our results suggest that earthworms at the ORNL FACE site directly contribute to the formation of soil aggregates, thus contributing to soil carbon sequestration. Carbon source within macroaggregates correspond with earthworm feeding

  10. Effect of steaming process on new formulation and physical properties of earthworm-based fish pellets for African catfish (Clarias gariepinus).

    PubMed

    Liam, Kulaab; Zakaria, Zarina; Gunny, Ahmad Anas Nagoor; Ishak, Mohd Azlan Mohd

    2014-09-01

    Fish feed has been recognized as one of main part/unit in aquaculture industry. However, current fish feed faces few challenges in terms of health aspects and cost issues. Alternatively, new nutritional and economical/low cost formulation of fish pellets was designed by combination of earthworm powder and other economical ingredients such as fishmeal, soybean waste, rice bran and tapioca flour. The formulation was calculated using Pearson's square and optimized by One-Factor-At-Time (OFAT) method. The effect of steaming processing on the water stability, soaking experiment, protein leaching test and breaking force of the earthworm-based fish pellets was investigated. Results indicate steam pellet at 80 degrees C for 40 min has higher water stability, less protein leaching and more durable than unsteam pellets. Introduction of this new formulation of fish meal is expected to provide essential nutrient, energy and improved the quality of pellets to fuel the growth of aquaculture industry. PMID:26031027

  11. Utilizing thin-film solid-phase extraction to assess the effect of organic carbon amendments on the bioavailability of DDT and dieldrin to earthworms

    USGS Publications Warehouse

    Andrade, Natasha A.; Centofanti, Tiziana; McConnell, Laura L.; Hapeman, Cathleen J.; Torrents, Alba; Anh, Nguyen; Beyer, W. Nelson; Chaney, Rufus L.; Novak, Jeffrey M.; Anderson, Marya O.; Cantrell, Keri B.

    2014-01-01

    Improved approaches are needed to assess bioavailability of hydrophobic organic compounds in contaminated soils. Performance of thin-film solid-phase extraction (TF-SPE) using vials coated with ethylene vinyl acetate was compared to earthworm bioassay (Lumbricus terrestris). A DDT and dieldrin contaminated soil was amended with four organic carbon materials to assess the change in bioavailability. Addition of organic carbon significantly lowered bioavailability for all compounds except for 4,4′-DDT. Equilibrium concentrations of compounds in the polymer were correlated with uptake by earthworms after 48d exposure (R2 = 0.97; p 40yr of aging. Results show that TF-SPE can be useful in examining potential risks associated with contaminated soils and to test effectiveness of remediation efforts.

  12. Interactions between organic matter and mineral surfaces along an earthworm invasion gradient in a sugar maple forest of Minnesota

    NASA Astrophysics Data System (ADS)

    Lyttle, A.; Yoo, K.; Aufdenkampe, A. K.; Sebestyen, S. D.; Hale, C.

    2012-12-01

    Sorption of organic matter on mineral surface is critical for protection of organic carbon (C) against decomposition and thus may potentially increase the capacity of soils to store C. Such sorption, however, requires physical contacts between organic matter and available mineral surfaces. This study attempts to better understand how bioturbation by invasive earthworms influences the contacts between organic matter and mineral surface, and affects sorption of organic matter on mineral surface. Vertical soil mixing is a direct consequence of the introduction of invasive earthworms in natural forests previously devoid of native earthworm populations. Here we focus on an intensively studied earthworm invasion chronosequence in a glaciated sugar maple forest in northern Minnesota. With the advance of invasive earthworms, leaf litter disappears while the A horizon expands at the expense of the overlying litter layer and the underlying wind blown silt materials. Earthworms' biomasses and functional group compositions, depth profiles of soil C contents, and total and organic matter-covered mineral surface areas are determined at different stages of invasion. We found that minerals' specific surface areas (SSA) in the A horizons decrease with greater degree of earthworm invasion. Furthermore, less fractions of mineral SSA were found to be coated with organic C in the soils with active earthworm populations. These observations appear to contradict another finding that amounts of crystalline Fe oxide and organically-complexed Fe increase with the greater earthworm population. The overall trend shows that earthworms' active mixing resulting in incorporating silt materials with low SSA from the underlying E horizons to the A horizons. We are currently investigating whether the increased crystalline Fe oxides and organically-complexed Fe pools with increasing earthworm population helped reducing the gradient of overall trend. Our study highlights the importance of earthworm

  13. Effects of HMX-lead mixtures on reproduction of the earthworm Eisenia andrei.

    PubMed

    Savard, Kathleen; Berthelot, Yann; Auroy, Aurelie; Spear, Philip A; Trottier, Bertin; Robidoux, Pierre Yves

    2007-10-01

    High metal (e.g., Pb) concentrations are typically found in explosive-contaminated soil, and their presence may increase, decrease, or not influence toxicity predicted on the basis of one explosive alone (e.g., HMX). Nevertheless, few data are available in the scientific literature for this type of multiple exposure. Soil organisms, such as earthworms, are one of the first receptors affected by the contamination of soil. Therefore, a reproductive study was conducted using Eisenia andrei in a forest-type soil. Both HMX and Pb decreased reproduction parameters (number of total cocoons, hatched cocoons, and surviving juveniles) individually. Based on the total number of cocoons, HMX was more toxic in a forest soil than Pb, with EC(50) of 31 mg kg(-1), and 1068 mg kg(-1), respectively. The slope of the concentration-response curve was significantly greater in the case of Pb, which is consistent with the possibility that the two compounds do not act on the same target site. The response-addition model was used to predict the response of earthworms and to test for interaction between the two contaminants. The predicted toxicity was not significantly different than the observed toxicity, implying that Pb and HMX were considered noninteractive compounds. The combined action of Pb-HMX may be described, therefore, as dissimilar-noninteractive joint action in a forest soil. The results illustrate the relevance of considering the presence of metals in the risk assessment of explosive-contaminated sites because metals can add their toxicity to explosives. Extension of this study to other types of soil and other metals would improve the understanding of toxicity at these sites. PMID:17690834

  14. Physiological and behavioural effects of imidacloprid on two ecologically relevant earthworm species (Lumbricus terrestris and Aporrectodea caliginosa).

    PubMed

    Dittbrenner, Nils; Triebskorn, Rita; Moser, Isabelle; Capowiez, Yvan

    2010-11-01

    Earthworms play key roles in soils and sub-lethal effects of environmental toxicants on these organisms should be taken seriously, since they might have detrimental effects on higher ecological levels. In laboratory experiments we have assessed sub-lethal effects (body mass change and cast production) of imidacloprid on two earthworm species commonly found in different agricultural soils (Lumbricus terrestris and Aporrectodea caliginosa). After 7 days of exposure in contaminated soil, a significant loss of body mass was found in both species exposed to imidacloprid concentrations as low as 0.66 mg kg(-1) dry soil. These losses ranged from 18.3 to 39% for A. caliginosa and from 7.4 to 32.4% for L. terrestris, respectively. Changes in cast production, a new biomarker previously validated using L. terrestris, was assessed by soil sieving using the recommended mesh size (5.6 mm) for L. terrestris and three different mesh sizes for A. caliginosa (5.6, 4 and 3.15 mm). The 4 mm mesh size proved to be the most suitable sieve size for A. caliginosa. Cast production increased by 26.2% in A. caliginosa and by 28.1% in L. terrestris at the lowest imidacloprid concentration tested (0.2 mg kg(-1) dry soil), but significantly decreased at higher concentrations (equal to and above 0.66 mg kg(-1) dry soil) in both earthworm species after the 7 days exposure experiment. These decreases in cast production ranged from 44.5 to 96.9% in A. caliginosa and from 42.4 to 95.7% in L. terrestris. The EC(50) for cast production were 0.84 (L. terrestris) and 0.76 mg kg(-1) dry soil (A. caliginosa), respectively. The detected sub-lethal effects were found close to the predicted environmental concentration (PEC) of imidacloprid, which is in the range of 0.33-0.66 mg kg(-1) dry soil. The biomarkers used in the present study, body mass change and changes in cast production, may be of ecological relevance and have shown high sensitivity for imidacloprid exposure of earthworms. The measurement of

  15. The Perceived-Threat Behavioral Approach Test (PT-BAT): Measuring Avoidance in High-, Mid-, and Low-Spider-Fearful Participants

    ERIC Educational Resources Information Center

    Cochrane, Andy; Barnes-Holmes, Dermot; Barnes-Holmes, Yvonne

    2008-01-01

    One hundred twenty female participants, with varying levels of spider fear were asked to complete an automated 8-step perceived-threat behavioral approach test (PT-BAT). The steps involved asking the participants if they were willing to put their hand into a number of opaque jars with an incrementally increasing risk of contact with a spider (none…

  16. Clostridiaceae and Enterobacteriaceae as active fermenters in earthworm gut content

    PubMed Central

    Wüst, Pia K; Horn, Marcus A; Drake, Harold L

    2011-01-01

    The earthworm gut provides ideal in situ conditions for ingested heterotrophic soil bacteria capable of anaerobiosis. High amounts of mucus- and plant-derived saccharides such as glucose are abundant in the earthworm alimentary canal, and high concentrations of molecular hydrogen (H2) and organic acids in the alimentary canal are indicative of ongoing fermentations. Thus, the central objective of this study was to resolve potential links between fermentations and active fermenters in gut content of the anecic earthworm Lumbricus terrestris by 16S ribosomal RNA (rRNA)-based stable isotope probing, with [13C]glucose as a model substrate. Glucose consumption in anoxic gut content microcosms was rapid and yielded soluble organic compounds (acetate, butyrate, formate, lactate, propionate, succinate and ethanol) and gases (carbon dioxide and H2), products indicative of diverse fermentations in the alimentary canal. Clostridiaceae and Enterobacteriaceae were users of glucose-derived carbon. On the basis of the detection of 16S rRNA, active phyla in gut contents included Acidobacteria, Actinobacteria, Bacteroidetes, Chloroflexi, Cyanobacteria, Firmicutes, Gemmatimonadetes, Nitrospirae, Planctomycetes, Proteobacteria, Tenericutes and Verrucomicrobia, taxa common to soils. On the basis of a 16S rRNA gene similarity cutoff of 87.5%, 82 families were detected, 17 of which were novel family-level groups. These findings (a) show the large diversity of soil taxa that might be active during gut passage, (b) show that Clostridiaceae and Enterobacteriaceae (fermentative subsets of these taxa) are selectively stimulated by glucose and might therefore be capable of consuming mucus- and plant-derived saccharides during gut passage and (c) indicate that ingested obligate anaerobes and facultative aerobes from soil can concomitantly metabolize the same source of carbon. PMID:20613788

  17. Clostridiaceae and Enterobacteriaceae as active fermenters in earthworm gut content.

    PubMed

    Wüst, Pia K; Horn, Marcus A; Drake, Harold L

    2011-01-01

    The earthworm gut provides ideal in situ conditions for ingested heterotrophic soil bacteria capable of anaerobiosis. High amounts of mucus- and plant-derived saccharides such as glucose are abundant in the earthworm alimentary canal, and high concentrations of molecular hydrogen (H(2)) and organic acids in the alimentary canal are indicative of ongoing fermentations. Thus, the central objective of this study was to resolve potential links between fermentations and active fermenters in gut content of the anecic earthworm Lumbricus terrestris by 16S ribosomal RNA (rRNA)-based stable isotope probing, with [(13)C]glucose as a model substrate. Glucose consumption in anoxic gut content microcosms was rapid and yielded soluble organic compounds (acetate, butyrate, formate, lactate, propionate, succinate and ethanol) and gases (carbon dioxide and H(2)), products indicative of diverse fermentations in the alimentary canal. Clostridiaceae and Enterobacteriaceae were users of glucose-derived carbon. On the basis of the detection of 16S rRNA, active phyla in gut contents included Acidobacteria, Actinobacteria, Bacteroidetes, Chloroflexi, Cyanobacteria, Firmicutes, Gemmatimonadetes, Nitrospirae, Planctomycetes, Proteobacteria, Tenericutes and Verrucomicrobia, taxa common to soils. On the basis of a 16S rRNA gene similarity cutoff of 87.5%, 82 families were detected, 17 of which were novel family-level groups. These findings (a) show the large diversity of soil taxa that might be active during gut passage, (b) show that Clostridiaceae and Enterobacteriaceae (fermentative subsets of these taxa) are selectively stimulated by glucose and might therefore be capable of consuming mucus- and plant-derived saccharides during gut passage and (c) indicate that ingested obligate anaerobes and facultative aerobes from soil can concomitantly metabolize the same source of carbon. PMID:20613788

  18. A structural equation model of soil metal bioavailability to earthworms: confronting causal theory and observations using a laboratory exposure to field-contaminated soils.

    PubMed

    Beaumelle, Léa; Vile, Denis; Lamy, Isabelle; Vandenbulcke, Franck; Gimbert, Frédéric; Hedde, Mickaël

    2016-11-01

    Structural equation models (SEM) are increasingly used in ecology as multivariate analysis that can represent theoretical variables and address complex sets of hypotheses. Here we demonstrate the interest of SEM in ecotoxicology, more precisely to test the three-step concept of metal bioavailability to earthworms. The SEM modeled the three-step causal chain between environmental availability, environmental bioavailability and toxicological bioavailability. In the model, each step is an unmeasured (latent) variable reflected by several observed variables. In an exposure experiment designed specifically to test this SEM for Cd, Pb and Zn, Aporrectodea caliginosa was exposed to 31 agricultural field-contaminated soils. Chemical and biological measurements used included CaC12-extractable metal concentrations in soils, free ion concentration in soil solution as predicted by a geochemical model, dissolved metal concentration as predicted by a semi-mechanistic model, internal metal concentrations in total earthworms and in subcellular fractions, and several biomarkers. The observations verified the causal definition of Cd and Pb bioavailability in the SEM, but not for Zn. Several indicators consistently reflected the hypothetical causal definition and could thus be pertinent measurements of Cd and Pb bioavailability to earthworm in field-contaminated soils. SEM highlights that the metals present in the soil solution and easily extractable are not the main source of available metals for earthworms. This study further highlights SEM as a powerful tool that can handle natural ecosystem complexity, thus participating to the paradigm change in ecotoxicology from a bottom-up to a top-down approach. PMID:27378153

  19. Relationship between hemolytic molecules in Eisenia fetida earthworms.

    PubMed

    Procházková, Petra; Silerová, Marcela; Felsberg, Jürgen; Josková, Radka; Beschin, Alain; De Baetselier, Patrick; Bilej, Martin

    2006-01-01

    The coelomic fluid of the earthworm Eisenia fetida has been reported to contain a variety of proteins causing the lysis of red blood cells-EFAF (Eisenia fetida andrei factor), fetidin, lysenin, eiseniapore, and hemolysins isolated either from coelomic fluid (H1, H2, H3) or from cell lysate (CL(39) and CL(41)). We document the presence of two distinct genes with a high level of homology. These genes encode fetidin and lysenin but their level of expression differs in individual E. fetida andrei animals. PMID:16051356

  20. Polychlorinated biphenyls (PCBs) depress allogeneic natural cytotoxicity by earthworm coelomocytes

    SciTech Connect

    Suzuki, M.M.; Cooper, E.L.; Eyambe, G.S.; Goven, A.J.; Fitzpatrick, L.C.; Venables, B.J. |

    1995-10-01

    Coelomocytes of the earthworm Lumbricus terrestris caused significant spontaneous allogeneic cytotoxicity in a 24-h trypan blue assay, but not in an assay using lactate dehydrogenase (LDH) release. Allogeneic cytotoxicity assays using cells from worms exposed to polychlorinated biphenyls (PCBs) suggest that PCBs can suppress a natural killing (NK-like) reaction. The implications of this work are twofold: understanding the evolution of natural killing (NK-like) activity and providing preliminary information on how spontaneous killing, a component of cellular immunity, may be compromised by pollutants.

  1. Concentration of cadmium in Coturnix quail fed earthworms

    SciTech Connect

    Stoewsand, G.S.; Bache, C.A.; Gutenmann, W.H.; Lisk, D.J.

    1986-01-01

    Earthworms (Lumbriscus terrestris), collected from soils in southern Ontario, Canada, that had no previous history of cadmium application, contained 3 ppm cadmium. They were fed to Coturnix quail as 60% dry weight of their diet for 63 d to examine the extent of deposition of native cadmium. Cadmium in kidney, liver, and excreta was greatly elevated above that of birds fed a control diet without worms. No increase in the level of cadmium in eggs was found. The factors affecting the association of cadmium in soils and worms and their assimilation and possible toxic effects in foraging birds are discussed.

  2. Earthworm populations as related to woodcock habitat usage in Central Maine

    USGS Publications Warehouse

    Reynolds, J.W.; Krohn, W.B.; Hordan, G.A.

    1977-01-01

    Lumbricid earthworms were sampled 'on two central Maine study areas between late April and early September, 1974, to relate earthworm abundance to use of feeding covers by American woodcock(Philoheli minor). On sampling days, occurring at 2 to 3 week intervals, a formalin solution was applied to thirty O.25m areas in heavjly, commonly, and rarely used woodcock covers (5 samples/type of feedjngcover/study area). The extent of cover usage was based on use of vegetation by 51 radio-equipped woodcock, 1970-73 (605 woodcockdays). A total of 2,546 earthworms of nine species was collected; species and age compositions of collected lumbricids were similar on both study areas. Similarly. number and biomass (dry weight) of earthworms extracted did not differ significantly between study areas. However. the number and biomass of sampled earthworms were directly and significantly related to the intensity to which woodcock used covers. Those diurnal covers most heavily used by woodcock sustained the highest lumbricid populations, ostensibly because these covers provided earthworms with preferred foods (i.e., leaf litters) and optimum soil moisture-temperature conditions. In terms of earthworms and woodcock supported per unit area, management of second-growth hardwoods appears more efficient than attempting to alter coniferous or mixed forests.

  3. Conserved lamin A protein expression in differentiated cells in the earthworm Eudrilus eugeniae.

    PubMed

    Kalidas, Ramamoorthy M; Raja, Subramanian Elaiya; Mydeen, Sheik Abdul Kader Nagoor Meeran; Samuel, Selvan Christyraj Johnson Retnaraj; Durairaj, Selvan Christyraj Jackson; Nino, Gopi D; Palanichelvam, Karuppaiah; Vaithi, Arumugaswami; Sudhakar, Sivasubramaniam

    2015-09-01

    Lamin A is an intermediate filament protein found in most of the differentiated vertebrate cells but absent in stem cells. It shapes the skeletal frame structure beneath the inner nuclear membrane of the cell nucleus. As there are few studies of the expression of lamin A in invertebrates, in the present work, we have analyzed the sequence, immunochemical conservation and expression pattern of lamin A protein in the earthworm Eudrilus eugeniae, a model organism for tissue regeneration. The expression of lamin A has been confirmed in E. eugeniae by immunoblot. Its localization in the nuclear membrane has been observed by immunohistochemistry using two different rabbit anti-sera raised against human lamin A peptides, which are located at the C-terminus of the lamin A protein. These two antibodies detected 70 kDa lamin A protein in mice and a single 65 kDa protein in the earthworm. The Oct-4 positive undifferentiated blastemal tissues of regenerating earthworm do not express lamin A, while the Oct-4 negative differentiated cells express lamin A. This pattern was also confirmed in the earthworm prostate gland. The present study is the first evidence for the immunochemical identification of lamin A and Oct-4 in the earthworm. Along with the partial sequence obtained from the earthworm genome, the present results suggest that lamin A protein and its expression pattern is conserved from the earthworm to humans. PMID:25858151

  4. Effects of heavy metals on the litter consumption by the earthworm Lumbricus rubellus in field soils

    USGS Publications Warehouse

    Hobbelen, P.H.F.; Koolhaas, J.E.; van Gestel, C.A.M.

    2006-01-01

    Aim of this study was to determine effects of heavy metals on litter consumption by the earthworm Lumbricus rubellus in National Park the "Brabantsche Biesbosch", the Netherlands. Adult L. rubellus were collected from 12 polluted and from one unpolluted field site. Earthworms collected at the unpolluted site were kept in their native soil and in soil from each of the 12 Biesbosch sites. Earthworms collected in the Biesbosch were kept in their native soils. Non-polluted poplar (Populus sp.) litter was offered as a food source and litter consumption and earthworm biomass were determined after 54 days. Cd, Cu and Zn concentrations were determined in soil, pore water and 0.01 M CaCl2 extracts of the soil and in earthworms. In spite of low available metal concentrations in the polluted soils, Cd, Cu and Zn concentrations in L. rubellus were increased. The litter consumption rate per biomass was positively related to internal Cd and Zn concentrations of earthworms collected from the Biesbosch and kept in native soil. A possible explanation is an increased demand for energy, needed for the regulation and detoxification of heavy metals. Litter consumption per biomass of earthworms from the reference site and kept in the polluted Biesbosch soils, was not related to any of the determined soil characteristics and metal concentrations. ?? 2005 Elsevier GmbH. All rights reserved.

  5. How within field abundance and spatial distribution patterns of earthworms and macropores depend on soil tillage

    NASA Astrophysics Data System (ADS)

    van Schaik, Loes; Palm, Juliane; Schröder, Boris

    2014-05-01

    Earthworms play a key role in soil systems. They are ecosystem engineers affecting soil structure as well as the transport and availability of water and solutes through their burrowing behaviour. There are three different ecological earthworm types with different burrowing behaviour that can result in varying local infiltration patterns: from rapid deep vertical infiltration to a stronger diffuse distribution of water and solutes in the upper soil layers. The small scale variation in earthworm abundance is often very high and within fields earthworm population processes might result in an aggregated pattern. The question arises how the local distribution of earthworms affects spatial distributions of macroporosity and how both are influenced by soil tillage. Therefore we performed a total number of 430 earthworm samplings on four differently tilled agricultural fields in the Weiherbach catchment (South East Germany). Additionally, at a limited amount of 32 locations on two of the fields we performed sprinkling experiments with brilliant blue and excavated the soil to count macropores at different soil depths (10 cm, 30 cm and 50 cm) to compare macropore distributions to the earthworm distributions.

  6. Impacts of epigeic, anecic and endogeic earthworms on metal and metalloid mobility and availability.

    PubMed

    Sizmur, Tom; Tilston, Emma L; Charnock, John; Palumbo-Roe, Barbara; Watts, Michael J; Hodson, Mark E

    2011-02-01

    The introduction of earthworms into soils contaminated with metals and metalloids has been suggested to aid restoration practices. Eisenia veneta (epigeic), Lumbricus terrestris (anecic) and Allolobophora chlorotica (endogeic) earthworms were cultivated in columns containing 900 g soil with 1130, 345, 113 and 131 mg kg(-1) of As, Cu, Pb and Zn, respectively, for up to 112 days, in parallel with earthworm-free columns. Leachate was produced by pouring water on the soil surface to saturate the soil and generate downflow. Ryegrass was grown on the top of columns to assess metal uptake into biota. Different ecological groups affected metals in the same way by increasing concentrations and free ion activities in leachate, but anecic L. terrestris had the greatest effect by increasing leachate concentrations of As by 267%, Cu by 393%, Pb by 190%, and Zn by 429% compared to earthworm-free columns. Ryegrass grown in earthworm-bearing soil accumulated more metal and the soil microbial community exhibited greater stress. Results are consistent with earthworm enhanced degradation of organic matter leading to release of organically bound elements. The degradation of organic matter also releases organic acids which decrease the soil pH. The earthworms do not appear to carry out a unique process, but increase the rate of a process that is already occurring. The impact of earthworms on metal mobility and availability should therefore be considered when inoculating earthworms into contaminated soils as new pathways to receptors may be created or the flow of metals and metalloids to receptors may be elevated. PMID:21161093

  7. Metallothionein gene expression differs in earthworm populations with different exposure history.

    PubMed

    Mustonen, M; Haimi, J; Väisänen, A; Knott, K E

    2014-11-01

    Metals are persistent pollutants in soils that can harm soil organisms and decrease species diversity. Animals can cope with metal contamination with the help of metallothioneins, small metal-binding proteins involved in homeostasis and detoxification of metals. We studied the expression of metallothionein with qPCR in a small, epigeic earthworm, Dendrobaena octaedra. We compared expression patterns and metal body content in earthworms collected from two sites with different metal contamination histories: Harjavalta, contaminated by a Cu-Ni smelter operational for over 50 years, and Jyväskylä, an uncontaminated site. Earthworms from both sites were also experimentally exposed to different concentrations of Cu (control, 50, 100 or 200 mg/kg) or Zn (control, 75, 150 or 300 mg/kg) for 7, 14 or 28 days to determine if there is a time related dose-response in gene expression. Population comparison showed that metallothionein expression was higher in earthworms from the contaminated site. In the exposure experiment, exposure time affected expression, but only in the earthworms from the uncontaminated site, suggesting that there is a delay in the metallothionein response of earthworms in this population. In contrast, earthworms from the contaminated site showed higher and constant levels of metallothionein expression at all exposure concentrations and durations. The constant metallothionein expression in earthworms from the contaminated site suggests that inducibility of metallothionein response could be lost in earthworms with metal exposure history. Adaptation of D. octaedra to metal exposure could explain the differences between the populations and explain the persistence of this species in contaminated forest soils. PMID:25179588

  8. Serum albumin and globulin analysis for hepatocellular carcinoma detection avoiding false-negative results from alpha-fetoprotein test negative subjects

    NASA Astrophysics Data System (ADS)

    Wang, Jing; Feng, Shangyuan; Lin, Juqiang; Zeng, Yongyi; Li, Ling; Huang, Zufang; Li, Buhong; Zeng, Haishan; Chen, Rong

    2013-11-01

    Surface-enhanced Raman spectroscopy (SERS) of serum albumin and globulin were employed to detect hepatocellular carcinoma (HCC). Tentative assignments of SERS bands show specific biomolecular changes associated with cancer development. These changes include a decrease in relative amounts of tryptophan, glutamine, glycine, and serine, indicating excessive consumption of amino acids for protein duplication. Principal component analysis was also introduced to analyze the obtained spectra, resulting in both diagnostic sensitivity and specificity of 100%. More importantly, it reveals that this method can detect HCC patients with alpha-fetoprotein negative test results, suggesting its great potential as a new alternative to detect HCC.

  9. Phoresy of the entomopathogenic nematode Steinernema feltiae by the earthworm Eisenia fetida.

    PubMed

    Campos-Herrera, Raquel; Trigo, Dolores; Gutiérrez, Carmen

    2006-05-01

    The free-living stage of entomopathogenic nematodes occurs in soil, and is an environmental-friendly alternative for biological control. However, their dispersal capability is limited. Earthworms improve soil characteristics, changing soil structure and influencing many edaphic organisms. Thus, earthworms could be used as vectors to introduce/disperse beneficial organisms. Nevertheless this interaction has not been studied in detail. This study presents the infectivity results of Steinernema feltiae after passing through the Eisenia fetida gut. Although entomopathogenic nematodes have no deleterious effects on earthworms, their passage through E. fetida gut seriously affected their mobility and virulence. PMID:16542677

  10. Soil Chemical Weathering and Nutrient Budgets along an Earthworm Invasion Chronosequence in a Northern Minnesota Forest

    NASA Astrophysics Data System (ADS)

    Resner, K. E.; Yoo, K.; Sebestyen, S. D.; Aufdenkampe, A. K.; Lyttle, A.; Weinman, B. A.; Blum, A.; Hale, C. M.

    2011-12-01

    We are investigating the impact of exotic earthworms on the rate of nutrient and ion release from soil chemical weathering along an ~200 m invasion chronosequence in a northern Minnesota sugar maple forest. The earthworms belong to three ecological groups that represent different feeding and burrowing behaviors, all of which were introduced from Europe to the previously earthworm-free Great Lakes Region through fishing and agricultural activities. As earthworms digest and mix the soil, we hypothesize that they significantly alter chemical weathering processes by incorporating mineral surfaces to new geochemical environments in their intestines and at different soil depths. The effect of mixing on soil morphology is dramatic, but biogeochemical changes remain largely unknown and therefore are poorly coupled to the current and potential changes in forest ecosystems under the threat of exotic earthworms. We analyze the activities of short-lived isotopes 137-Cs and 210-Pb along with the inorganic chemistry of soil, water, and leaf litter across an invasion transect and link these measurements to the biomass and species composition of exotic earthworms. Earthworms vertically relocate minerals and organic matter largely within the top ~10 cm, which is reflected in the depth profiles of the short-lived isotopes. Among the inorganic nutrients analyzed, Ca is of particular interest due to sugar maple's aptitude for recycling Ca. Fractional mass loss values (tau) of Ca, relative to the soil's parent material, show an enrichment factor of 14 in the least invaded A horizon soils. However, such a high enrichment factor declines dramatically in the heavily invaded soils, suggesting that earthworm activities contribute to leaching Ca. In contrast, the enrichment factor of Fe increases with greater degrees of earthworm invasion, which is consistent with the extraction chemistry data showing greater quantities of pedogenic crystalline iron oxides and greater mineral specific

  11. Using of ants and earthworm to modify of soil biological quality and its effect on cocoa seedlings growth

    NASA Astrophysics Data System (ADS)

    Kilowasid, Laode Muhammad Harjoni; Budianto, Wayan; Syaf, Hasbullah; Tufaila, Muhammad; Safuan, La Ode

    2015-09-01

    Ant and earthworm can act as soil ecosystem engineers. Ant and earthworm are very dominant in smallholder cocoa plantation. The first experiment aimed to study the effect of the abundance of ants and earthworms on soil microbial activity and microfauna, and the second experiment to analyse the effect of soil modified by ants and earthworms on the cocoa seedlings growth. Ant (Ponera sp.) and earthworm (Pontoscolex sp.) collected from smallholder cocoa plantation, and kept in a container up to applied. In the first experiment, nine combinations of the abundance of ants and earthworms applied to each pot containing 3 kg of soil from smallholder cocoa plantation, and each combination of the abundance was repeated five times in a completely randomized design. After the soil was incubated for thirty days, ants and earthworms removed from the soil using hand sorting techniques. Soil from each pot was analysed for soil microbial activity, abundance of flagellates and nematodes. In the second experiment, the soil in each pot was planted with cocoa seedlings and maintained up to ninety days. The results showed the FDA hydrolytic activity of microbes, the abundance of flagellates and nematodes between the combination of the abundance of ants and earthworms have been significantly different. Dry weight of root, shoot and seedling cacao have been significantly different between the combination of the abundance of ants and earthworms. It was concluded that the combination of the abundance of ants and earthworms can be used in ecological engineering to improve soil quality.

  12. Potential effects of earthworm activity on C and N dynamics in tropical paddy soil

    NASA Astrophysics Data System (ADS)

    John, Katharina; Zaitsev, Andrey S.; Wolters, Volkmar

    2016-04-01

    Earthworms are involved in key ecosystem processes and are generally considered important for sustainable crop production. However, their provision of essential ecosystem services and contribution to tropical soil carbon and nitrogen balance in rice-based agroecosystems are not yet completely understood. We carried out two microcosm experiments to quantify the impact of a tropical earthworm Pheretima sp. from the Philippines on C and N turnover in rice paddy soils. First one was conducted to understand the modulation impact of soil water saturation level and nitrogen fertilizer input intensity on C and N cycles. The second one focused on the importance of additional organic matter (rice straw) amendment on the earthworm modulation of mineralization in non-flooded conditions. We measured CO2, CH4 (Experiments 1 and 2) and N2O evolution (Experiment 2) from rice paddy soil collected at the fields of the International Rice Research Institute (Philippines). Further we analysed changes in soil C and N content as well as nutrient loss via leaching induced by earthworms (Experiment 2). Addition of earthworms resulted in the strong increase of CH4 release under flooded conditions as well as after rice straw amendment. Compared to flooded conditions, earthworms suppressed the distinct CO2 respiration maximum at intermediate soil water saturation levels. In the first few days after the experiment establishment (Experiment 1) intensive nitrogen application resulted in the suppression of CO2 emission by earthworms at non-flooded soil conditions. However, at the longer term perspective addressed in the second experiment (30 days) earthworm activity rather increased average soil respiration under intensive fertilization or rice straw amendment. The lowest N2O release rates were revealed in the microcosms with earthworm and straw treatments. The combined effect of N fertilizer and straw addition to microcosms resulted in the increased leachate volume due to earthworm bioturbation

  13. Avoidable waste management costs

    SciTech Connect

    Hsu, K.; Burns, M.; Priebe, S.; Robinson, P.

    1995-01-01

    This report describes the activity based costing method used to acquire variable (volume dependent or avoidable) waste management cost data for routine operations at Department of Energy (DOE) facilities. Waste volumes from environmental restoration, facility stabilization activities, and legacy waste were specifically excluded from this effort. A core team consisting of Idaho National Engineering Laboratory, Los Alamos National Laboratory, Rocky Flats Environmental Technology Site, and Oak Ridge Reservation developed and piloted the methodology, which can be used to determine avoidable waste management costs. The method developed to gather information was based on activity based costing, which is a common industrial engineering technique. Sites submitted separate flow diagrams that showed the progression of work from activity to activity for each waste type or treatability group. Each activity on a flow diagram was described in a narrative, which detailed the scope of the activity. Labor and material costs based on a unit quantity of waste being processed were then summed to generate a total cost for that flow diagram. Cross-complex values were calculated by determining a weighted average for each waste type or treatability group based on the volume generated. This study will provide DOE and contractors with a better understanding of waste management processes and their associated costs. Other potential benefits include providing cost data for sites to perform consistent cost/benefit analysis of waste minimization and pollution prevention (WMIN/PP) options identified during pollution prevention opportunity assessments and providing a means for prioritizing and allocating limited resources for WMIN/PP.

  14. Earthworm coelomocytes as nanoscavenger of ZnO NPs

    NASA Astrophysics Data System (ADS)

    Gupta, Shruti; Kushwah, Tanuja; Yadav, Shweta

    2014-05-01

    Earthworms can `biotransform' or `biodegrade' chemical contaminants, rendering them harmless in their bodies, and can bioaccumulate them in their tissues. They `absorb' the dissolved chemicals through their moist `body wall' due to the interstitial water and also ingest by `mouth' while soil passes through the gut. Since the advent of the nanotechnology era, the environmental sink has been continuously receiving engineered nanomaterials as well as their derivatives. Our current understanding of the potential impact of nanomaterials and their natural scavenger is limited. In the present investigation, we studied the cellular uptake of ZnO nanoparticles (NPs) by coelomocytes especially by chloragocytes of Eisenia fetida and their role as nanoscavenger. Results from exposure to 100- and 50-nm ZnO NPs indicate that coelomocytes of the earthworm E. fetida show no significant DNA damage at a dose lower than 3 mg/l and have the potential ability to uptake ZnO NPs from the soil ecosystem and transform them into microparticles.

  15. Biosynthesis of luminescent quantum dots in an earthworm

    NASA Astrophysics Data System (ADS)

    Stürzenbaum, S. R.; Höckner, M.; Panneerselvam, A.; Levitt, J.; Bouillard, J.-S.; Taniguchi, S.; Dailey, L.-A.; Khanbeigi, R. Ahmad; Rosca, E. V.; Thanou, M.; Suhling, K.; Zayats, A. V.; Green, M.

    2013-01-01

    The synthesis of designer solid-state materials by living organisms is an emerging field in bio-nanotechnology. Key examples include the use of engineered viruses as templates for cobalt oxide (Co3O4) particles, superparamagnetic cobalt-platinum alloy nanowires and gold-cobalt oxide nanowires for photovoltaic and battery-related applications. Here, we show that the earthworm's metal detoxification pathway can be exploited to produce luminescent, water-soluble semiconductor cadmium telluride (CdTe) quantum dots that emit in the green region of the visible spectrum when excited in the ultraviolet region. Standard wild-type Lumbricus rubellus earthworms were exposed to soil spiked with CdCl2 and Na2TeO3 salts for 11 days. Luminescent quantum dots were isolated from chloragogenous tissues surrounding the gut of the worm, and were successfully used in live-cell imaging. The addition of polyethylene glycol on the surface of the quantum dots allowed for non-targeted, fluid-phase uptake by macrophage cells.

  16. The binding interactions of imidacloprid with earthworm fibrinolytic enzyme

    NASA Astrophysics Data System (ADS)

    Wang, Yan-Qing; Zhang, Hong-Mei; Chen, Tao

    2014-08-01

    In this paper, several studies were conducted to elucidate the binding mechanism of earthworm fibrinolytic enzyme (EFE) with imidocloprid (IMI) by using theoretical calculation, fluorescence, UV-vis, circular dichroism spectroscopy and an enzymatic inhibition assay. The spectral data showed that the binding interactions existed between IMI and EFE. The binding constants, binding site, thermodynamic parameters and binding forces were analyzed in detail. The results indicate a single class of binding sites for IMI in EFE and that this binding interaction is a spontaneous process with the estimated enthalpy and entropy changes being 2.195 kJ mol-1 and 94.480 J mol-1 K-1, respectively. A single class of binding site existed for IMI in EFE. The tertiary or secondary structure of EFE was partly destroyed by IMI. The visualized binding details were also exhibited by the theoretical calculation and the results indicated that the interaction between IMI and Phe (Tyr, or Trp) or EFE occurred. Combining the experimental data with the theoretical calculation data, we showed that the binding forces between IMI and EFE were mainly hydrophobic force accompanied by hydrogen binding, and π-π stacking. In addition, IMI did not obviously influence the activity of EFE. In a word, the above analysis offered insights into the binding mechanism of IMI with EFE and could provide some important information for the molecular toxicity of IMI for earthworms.

  17. Earthworm ecology affects the population structure of their Verminephrobacter symbionts.

    PubMed

    Viana, Flávia; Jensen, Christopher Erik; Macey, Michael; Schramm, Andreas; Lund, Marie Braad

    2016-05-01

    Earthworms carry species-specific Verminephrobacter symbionts in their nephridia (excretory organs). The symbionts are vertically transmitted via the cocoon, can only colonize the host during early embryonic development, and have co-speciated with their host for about 100 million years. Although several studies have addressed Verminephrobacter diversity between worm species, the intra-species diversity of the symbiont population has never been investigated. In this study, symbiont population structure was examined by using a multi-locus sequence typing (MLST) approach on Verminephrobacter isolated from two contrasting ecological types of earthworm hosts: the high population density, fast reproducing compost worms, Eisenia andrei and Eisenia fetida, and the low-density, slow reproducing Aporrectodea tuberculata, commonly found in garden soils. Three distinct populations were investigated for both types and, according to MLST analysis of 193 Verminephrobacter isolates, the symbiont community in each worm individual was very homogeneous. The more solitary A. tuberculata carried unique symbiont populations in 9 out of 10 host individuals, whereas the symbiont populations in the social compost worms were homogeneous across host individuals from the same population. These data suggested that host ecology shaped the population structure of Verminephrobacter symbionts. The homogeneous symbiont populations in the compost worms led to the hypothesis that Verminephrobacter could be transferred bi-parentally or via leaky horizontal transmission in high-density, frequently mating worm populations. PMID:27040820

  18. Differences in scaling and morphology between lumbricid earthworm ecotypes.

    PubMed

    Kurth, Jessica A; Kier, William M

    2015-09-01

    Many soft-bodied invertebrates use a flexible, fluid-filled hydrostatic skeleton for burrowing. The aim of our study was to compare the scaling and morphology between surface-dwelling and burrowing earthworm ecotypes to explore the specializations of non-rigid musculoskeletal systems for burrowing locomotion. We compared the scaling of adult lumbricid earthworms across species and ecotypes to determine whether linear dimensions were significantly associated with ecotype. We also compared the ontogenetic scaling of a burrowing species, Lumbricus terrestris, and a surface-dwelling species, Eisenia fetida, using glycol methacrylate histology. We show that burrowing species are longer, thinner and have higher length-to-diameter ratios than non-burrowers, and that L. terrestris is thinner for any given body mass compared with E. fetida. We also found differences in the size of the musculature between the two species that may correlate with surface crawling or burrowing. Our results suggest that adaptations to burrowing for soft-bodied animals include a disproportionately thin body and strong longitudinal muscles. PMID:26232418

  19. Scaling of the hydrostatic skeleton in the earthworm Lumbricus terrestris.

    PubMed

    Kurth, Jessica A; Kier, William M

    2014-06-01

    The structural and functional consequences of changes in size or scale have been well studied in animals with rigid skeletons, but relatively little is known about scale effects in animals with hydrostatic skeletons. We used glycol methacrylate histology and microscopy to examine the scaling of mechanically important morphological features of the earthworm Lumbricus terrestris over an ontogenetic size range from 0.03 to 12.89 g. We found that L. terrestris becomes disproportionately longer and thinner as it grows. This increase in the length to diameter ratio with size means that, when normalized for mass, adult worms gain ~117% mechanical advantage during radial expansion, compared with hatchling worms. We also found that the cross-sectional area of the longitudinal musculature scales as body mass to the ~0.6 power across segments, which is significantly lower than the 0.66 power predicted by isometry. The cross-sectional area of the circular musculature, however, scales as body mass to the ~0.8 power across segments, which is significantly higher than predicted by isometry. By modeling the interaction of muscle cross-sectional area and mechanical advantage, we calculate that the force output generated during both circular and longitudinal muscle contraction scales near isometry. We hypothesize that the allometric scaling of earthworms may reflect changes in soil properties and burrowing mechanics with size. PMID:24871920

  20. Neurotropic and neuroprotective activities of the earthworm peptide Lumbricusin

    SciTech Connect

    Kim, Dae Hong; Lee, Ik Hwan; Nam, Seung Taek; Hong, Ji; Zhang, Peng; Hwang, Jae Sam; Seok, Heon; Choi, Hyemin; Lee, Dong Gun; Kim, Jae Il; Kim, Ho

    2014-06-06

    Highlights: • 11-mer peptide Lumbricusin, a defensin like peptide, is isolated from earthworm. • We here demonstrated that Lumbricusin has neurotropic and neuroprotective effects. • p27 degradation by Lumbricusin mediates effects of Lumbricusin on neuronal cells. - Abstract: We recently isolated a polypeptide from the earthworm Lumbricus terrestris that is structurally similar to defensin, a well-known antibacterial peptide. An 11-mer antibacterial peptide (NH{sub 2}-RNRRWCIDQQA), designated Lumbricusin, was synthesized based on the amino acid sequence of the isolated polypeptide. Since we previously reported that CopA3, a dung beetle peptide, enhanced neuronal cell proliferation, we here examined whether Lumbricusin exerted neurotropic and/or neuroprotective effects. Lumbricusin treatment induced a time-dependent increase (∼51%) in the proliferation of human neuroblastoma SH-SY5Y cells. Lumbricusin also significantly inhibited the apoptosis and decreased viability induced by treatment with 6-hydroxy dopamine, a Parkinson’s disease-mimicking agent. Immunoblot analyses revealed that Lumbricusin treatment increased ubiquitination of p27{sup Kip1} protein, a negative regulator of cell-cycle progression, in SH-SY5Y cells, and markedly promoted its degradation. Notably, adenoviral-mediated over-expression of p27{sup Kip1} significantly blocked the antiapoptotic effect of Lumbricusin in 6-hydroxy dopamine-treated SH-SY5Y cells. These results suggest that promotion of p27{sup Kip1} degradation may be the main mechanism underlying the neuroprotective and neurotropic effects of Lumbricusin.

  1. Earthworm coelomocytes as nanoscavenger of ZnO NPs

    PubMed Central

    2014-01-01

    Earthworms can ‘biotransform’ or ‘biodegrade’ chemical contaminants, rendering them harmless in their bodies, and can bioaccumulate them in their tissues. They ‘absorb’ the dissolved chemicals through their moist ‘body wall’ due to the interstitial water and also ingest by ‘mouth’ while soil passes through the gut. Since the advent of the nanotechnology era, the environmental sink has been continuously receiving engineered nanomaterials as well as their derivatives. Our current understanding of the potential impact of nanomaterials and their natural scavenger is limited. In the present investigation, we studied the cellular uptake of ZnO nanoparticles (NPs) by coelomocytes especially by chloragocytes of Eisenia fetida and their role as nanoscavenger. Results from exposure to 100- and 50-nm ZnO NPs indicate that coelomocytes of the earthworm E. fetida show no significant DNA damage at a dose lower than 3 mg/l and have the potential ability to uptake ZnO NPs from the soil ecosystem and transform them into microparticles. PMID:24959107

  2. Growth and reproduction of earthworms in ultramafic soils.

    PubMed

    Maleri, R; Reinecke, S A; Mesjasz-Przybylowicz, J; Reinecke, A J

    2007-04-01

    Ultramafic soils are characterized by high concentrations of heavy metals of natural origin-such as chromium, cobalt, manganese, and nickel-as well as a shortage of primary nutrients. This can result in extremely disadvantageous living conditions for all soil-dwelling organisms. Responses to these conditions were addressed by studying growth, cocoon production, and fecundity of earthworms as endpoints of sublethal effects and how this influences the reproductive system and, consequently, population development. Mature specimens of two ecophysiologically different species of earthworms, Eisenia fetida (Savigny) and Aporrectodea caliginosa (Savigny), were exposed for 56 days to an uncontaminated soil and ultramafic soils collected from six ultramafic sites in the Barberton greenstone belt. In all ultramafic soil samples, the specimens of both species grew slower than those in the control soil. In A. caliginosa, an autotomization of the tail section was observed at higher concentrations of heavy metals. At high levels of heavy metals such as manganese, chromium, nickel, and cobalt, a significantly lower cocoon production was recorded for E. fetida, and at medium levels, a time delay in cocoon production was found. A. caliginosa showed an increase in production at medium levels and a decrease at high levels of heavy metals. In both species, no correlation between growth and cocoon viability was found, indicating different target levels for toxicants present in ultramafic soils. To determine effects of these soils on population dynamics, hatching success may be a more useful endpoint of reproduction. PMID:17354041

  3. Abandoned coal mining sites: using ecotoxicological tests to support an industrial organic sludge amendment.

    PubMed

    Chiochetta, Claudete G; Radetski, Marilice R; Corrêa, Albertina X R; Tischer, Vinícius; Tiepo, Erasmo N; Radetski, Claudemir M

    2013-11-01

    The different stages involved in coal mining-related activities result in a degraded landscape and sites associated with large amounts of dumped waste material. Remediation of these contaminated soils can be carried out by application of industrial organic sludge if the concerns regarding the potential negative environmental impacts of this experimental practice are properly addressed. In this context, the objective of this study was to use ecotoxicological tests to determine the quantity of organic industrial sludge that is required as a soil amendment to restore soil production while avoiding environmental impact. Chemical analysis of the solids (industrial sludge and soil) and their leachates was carried out as well as a battery of ecotoxicity tests on enzymes (hydrolytic activity), bacteria, algae, daphnids, earthworms, and higher plants, according to standardized methodologies. Solid and leachate samples of coal-contaminated soil were more toxic than those of industrial sludge towards enzyme activity, bacteria, algae, daphnids, and earthworms. In the case of the higher plants (lettuce, corn, wild cabbage, and Surinam cherry) the industrial sludge was more toxic than the coal-contaminated soil, and a soil/sludge mixture (66:34% dry weight basis) had a stimulatory effect on the Surinam cherry biomass. The ecotoxicological assessment of the coal-contaminated soil remediation using sludge as an amendment is very important to determine application rates that could promote a stimulatory effect on agronomic species without negatively affecting the environment. PMID:23114837

  4. Human Papillomavirus Genotyping and p16INK4a Expression in Cervical Lesions: A Combined Test to Avoid Cervical Cancer Progression

    PubMed Central

    Zouheir, Yassine; Fechtali, Taoufiq; Elgnaoui, Nadia

    2016-01-01

    Cervical cancer is a major public health problem in Morocco. The cervical cancer has a long precancerous period that provides an opportunity for the screening and treatment. Improving screening tests is a priority goal for the early diagnosis of cervical cancer. This study was conducted to evaluate the combination of p16INK4a protein expression, human papillomavirus (HPV) typing, and histopathology for the identification of cervical lesions with high risk to progress to cervical cancer among Moroccan women. A total of 96 cervical biopsies were included in this study. Signal amplification in situ hybridization with biotinylated probes was used to detect HPV. Immunohistochemistry was used to evaluate the expression of p16INK4a protein. HPV DNA was detected in 74.0% of the biopsies (71/96). Of the seventy-one positive HPV cases, we detected 67.6% (48/71) of high risk (HR)-HPV (HPV 16 and 18), 24% of low risk-HPV (HPV 6 and 11), 1.4% intermediate risk-HPV (HPV 31, 33, and 35), and 7% coinfections (HPV 6/11 and 16/18). Overexpression of p16INK4a protein was observed in 72.9% (70/96) of the biopsies. In addition, p16INK4a protein detection was closely correlated with recovery of HR HPV. Our result showed that p16INK4a expression level is correlated with HR-HPV status. PMID:27390742

  5. Human Papillomavirus Genotyping and p16(INK4a) Expression in Cervical Lesions: A Combined Test to Avoid Cervical Cancer Progression.

    PubMed

    Zouheir, Yassine; Fechtali, Taoufiq; Elgnaoui, Nadia

    2016-06-01

    Cervical cancer is a major public health problem in Morocco. The cervical cancer has a long precancerous period that provides an opportunity for the screening and treatment. Improving screening tests is a priority goal for the early diagnosis of cervical cancer. This study was conducted to evaluate the combination of p16(INK4a) protein expression, human papillomavirus (HPV) typing, and histopathology for the identification of cervical lesions with high risk to progress to cervical cancer among Moroccan women. A total of 96 cervical biopsies were included in this study. Signal amplification in situ hybridization with biotinylated probes was used to detect HPV. Immunohistochemistry was used to evaluate the expression of p16(INK4a) protein. HPV DNA was detected in 74.0% of the biopsies (71/96). Of the seventy-one positive HPV cases, we detected 67.6% (48/71) of high risk (HR)-HPV (HPV 16 and 18), 24% of low risk-HPV (HPV 6 and 11), 1.4% intermediate risk-HPV (HPV 31, 33, and 35), and 7% coinfections (HPV 6/11 and 16/18). Overexpression of p16(INK4a) protein was observed in 72.9% (70/96) of the biopsies. In addition, p16(INK4a) protein detection was closely correlated with recovery of HR HPV. Our result showed that p16(INK4a) expression level is correlated with HR-HPV status. PMID:27390742

  6. Testing the credibility, feasibility and acceptability of an optimised behavioural intervention (OBI) for avoidant chronic low back pain patients: protocol for a randomised feasibility study

    PubMed Central

    2013-01-01

    Background Chronic back pain continues to be a costly and prevalent condition. The latest NICE guidelines issued in 2009 state that for patients with persistent back pain (of between six weeks and twelve months duration), who are highly distressed and/or disabled and for whom exercise, manual therapy and acupuncture has not been beneficial, the evidence supports a combination of around 100 hours of combined physical and psychological treatment. This is costly, and may prove unacceptable to many patients. A key recommendation of these guidelines was for further randomised controlled trials (RCTs) of psychological treatment and to target treatment to specific sub-groups of patients. Recent trials that have included psychological interventions have shown only moderate improvement at best, and results are not maintained long term. There is therefore a need to test theoretically driven interventions that focus on specific high-risk sub-groups, in which the intervention is delivered at full integrity against a credible control. Methods/design A feasibility study of a pragmatic randomised controlled trial comparing psychologist-delivered Contextual Cognitive Behavioural Therapy (CCBT) against Treatment As Usual (TAU) physiotherapy delivered by physiotherapists for the treatment of chronic lower back pain in ‘avoidant’ patients. Ninety-two patients referred for physiotherapy will be recruited and randomised on a 1:1 basis to receive CCBT or TAU. Treatment groups will be balanced by centre and pain interference score. Primary outcomes include assessing the credibility and acceptability of the intervention, and to demonstrate proof of principle through a greater change in pain acceptance in the CCBT arm, measured by the Acceptance and Action –II and the Chronic Pain Acceptance questionnaires. In addition, the feasibility of carrying out a full trial will be explored with reference to recruitment and follow-up rates including the assessment of the burden of outcome

  7. Avoiding dangerous climate change

    SciTech Connect

    Hans Joachim Schellnhuber; Wolfgang Cramer; Nebojsa Nakicenovic; Tom Wigley; Gary Yohe

    2006-02-15

    In 2005 the UK Government hosted the Avoiding Dangerous Climate Change conference to take an in-depth look at the scientific issues associated with climate change. This volume presents the most recent findings from the leading international scientists that attended the conference. The topics addressed include critical thresholds and key vulnerabilities of the climate system, impacts on human and natural systems, socioeconomic costs and benefits of emissions pathways, and technological options for meeting different stabilisation levels of greenhouse gases in the atmosphere. Contents are: Foreword from Prime Minister Tony Blair; Introduction from Rajendra Pachauri, Chairman of the IPCC; followed by 41 papers arranged in seven sections entitled: Key Vulnerabilities of the Climate System and Critical Thresholds; General Perspectives on Dangerous Impacts; Key Vulnerabilities for Ecosystems and Biodiversity; Socio-Economic Effects; Regional Perspectives; Emission Pathways; and Technological Options. Four papers have been abstracted separately for the Coal Abstracts database.

  8. Joint acute toxicity of the herbicide butachlor and three insecticides to the terrestrial earthworm, Eisenia fetida.

    PubMed

    Wang, Yanhua; Cang, Tao; Yu, Ruixian; Wu, Shenggan; Liu, Xinju; Chen, Chen; Wang, Qiang; Cai, Leiming

    2016-06-01

    The herbicide butachlor and three insecticides phoxim, chlorpyrifos, and lambda-cyhalotrhin are widely used pesticides with different modes of action. As most previous laboratory bioassays for these pesticides have been conducted solely based on acute tests with a single compound, only limited information is available on the possible combined toxicity of these common chemicals to soil organisms. In this study, we evaluated their mixture toxicity on the terrestrial earthworm, Eisenia fetida, with binary, ternary, and quaternary mixtures. Two different types of bioassays were employed in our work, including a contact filter paper toxicity test and a soil toxicity test. Mixture toxicity effects were assessed using the additive index method. For all of the tested binary mixtures (butachlor-phoxim, butachlor-chlorpyrifos, and butachlor-lambda-cyhalothrin), significant synergistic interactions were observed after 14 days in the soil toxicity assay. However, greater additive toxicity was found after 48 h in the contact toxicity bioassay. Most of the ternary and quaternary mixtures exhibited significant synergistic effects on the worms in both bioassay systems. Our findings would be helpful in assessing the ecological risk of these pesticide mixtures to soil invertebrates. The observed synergistic interactions underline the necessity to review soil quality guidelines, which are likely underestimating the adverse combined effects of these compounds. PMID:26946506

  9. Interactions between plant species and earthworm casts in a calcareous grassland under elevated CO{sub 2}

    SciTech Connect

    Zaller, J.G.; Arnone, J.A. III

    1999-04-01

    The authors tested the hypothesis that the spatial proximity of a plant species to nutrient-rich earthworm casts (e.g., 100% more ammonium and 30% more phosphate than in adjacent soil) is an important determinant of a plant`s responsiveness to elevated atmospheric CO{sub 2}. In 1995 the authors mapped the location of both earthworm surface casts and plants in each of 16 1.2-m{sup 2} plots in a species-rich calcareous grassland in northwestern Switzerland. Eight plots have been maintained under current ambient CO{sub 2} concentrations and eight have been maintained at elevated CO{sub 2} since March 1994. In addition, total ramet production of each species, as a measure of performance, and cumulative cast production at each location (cell) were recorded at peak community biomass in 1995. Plant species within functional groups differed markedly in their degree of association with casts; however, after two growing seasons elevated CO{sub 2} had no effect on plant species or functional group associations with casts. No statistically significant relationship could be demonstrated between plant-species response to elevated CO{sub 2} and the degree of association with casts within any of the functional groups. However, a positive relationship was observed between the mean response of graminoid species to elevated CO{sub 2} and their mean degree of association with surface casts at ambient CO{sub 2}.

  10. Measuring Experiential Avoidance in Adults: The Avoidance and Fusion Questionnaire

    ERIC Educational Resources Information Center

    Schmalz, Jonathan E.; Murrell, Amy R.

    2010-01-01

    To date, general levels of experiential avoidance are primarily measured by the Acceptance and Action Questionnaire-II (AAQ-II), but it includes items of questionable comprehensibility. The Avoidance and Fusion Questionnaire for Youth (AFQ-Y), previously validated as a measure of experiential avoidance with children and adolescents, was…

  11. Taxonomic composition and physiological and biochemical properties of bacteria in the digestive tracts of earthworms

    NASA Astrophysics Data System (ADS)

    Byzov, B. A.; Tikhonov, V. V.; Nechitailo, T. Yu.; Demin, V. V.; Zvyagintsev, D. G.

    2015-03-01

    Several hundred bacterial strains belonging to different taxa were isolated and identified from the digestive tracts of soil and compost earthworms. Some physiological and biochemical properties of the bacteria were characterized. The majority of intestinal bacteria in the earthworms were found to be facultative anaerobes. The intestinal isolates as compared to the soil ones had elevated activity of proteases and dehydrogenases. In addition, bacteria associated with earthworms' intestines are capable of growth on humic acids as a sole carbon source. Humic acid stimulated the growth of the intestinal bacteria to a greater extent than those of the soil ones. In the digestive tracts, polyphenol oxidase activity was found. Along with the data on the taxonomic separation of the intestinal bacteria, the features described testified to the presence of a group of bacteria in the earthworms intestines that is functionally characteristic and is different from the soil bacteria.

  12. Glyphosate herbicide affects belowground interactions between earthworms and symbiotic mycorrhizal fungi in a model ecosystem

    PubMed Central

    Zaller, Johann G.; Heigl, Florian; Ruess, Liliane; Grabmaier, Andrea

    2014-01-01

    Herbicides containing glyphosate are widely used in agriculture and private gardens, however, surprisingly little is known on potential side effects on non-target soil organisms. In a greenhouse experiment with white clover we investigated, to what extent a globally-used glyphosate herbicide affects interactions between essential soil organisms such as earthworms and arbuscular mycorrhizal fungi (AMF). We found that herbicides significantly decreased root mycorrhization, soil AMF spore biomass, vesicles and propagules. Herbicide application and earthworms increased soil hyphal biomass and tended to reduce soil water infiltration after a simulated heavy rainfall. Herbicide application in interaction with AMF led to slightly heavier but less active earthworms. Leaching of glyphosate after a simulated rainfall was substantial and altered by earthworms and AMF. These sizeable changes provide impetus for more general attention to side-effects of glyphosate-based herbicides on key soil organisms and their associated ecosystem services. PMID:25005713

  13. NON-INVASIVE ELECTROPHYSIOLOGICAL MONITORING: A SENSITIVE METHOD FOR DETECTING SUBLETHAL NEUROTOXICITY IN EARTHWORMS

    EPA Science Inventory

    Earthworms were exposed, by external surface contact, to three chemical pollutants: dieldrin (a known neurotoxicant), dimethyl phthalate and fluorene (a possible neurotoxicant). After 48 h of exposure, LC50 values were determined and compared with concentrations required for subl...

  14. METAL CONTENT OF EARTHWORMS IN SLUDGE AMENDED SOILS: UPTAKE AND LOSS

    EPA Science Inventory

    The widespread practice of landspreading of sludge has raised concern about increasing concentrations of potentially toxic metals in soils, with the possibility of these metals adversely impacting terrestrial and aquatic ecosystems. Earthworms, as one of the largest components of...

  15. Review of the earthworm fauna of Iran with emphasis on Kohgiluyeh & Boyer-Ahmad Province.

    PubMed

    Farhadi, Zeinab; Malek, Masoumeh; Elahi, Elahe

    2013-01-01

    Earthworms were collected in forests, damp habitats, springs, orchards and agricultural fields of the Kohgiluyeh & Boyer Ahmad Province, Iran, from April 2009 to April 2010. Specimens were collected at 20 established stations by digging and by diluted formalin methods. Ten species belonging to family Lumbricidae were identified based on morphology: Aporrectodea caliginosa (Savigny, 1826), Ap. rosea (Savigny, 1826), Ap. jassyensis (Michaelsen, 1891), Dendrobaena veneta (Rosa, 1886), D. byblica (Rosa, 1893) complex, D. orientalis orientalis Cernosvitov 1940, Eisenia fetida (Savigny, 1826), Eiseniella tetraedra (Savigny, 1826), Octolasion lacteum (Örley, 1881), Perelia kaznakovi (Michaelsen, 1910). Ap. caliginosa was the dominant species in this province and D. orientalis orientalis is a new record for Iran. A checklist of all earthworms species form Iran is presented, containing 19 species. Then, in order to show earthworm geographical affinities, hierarchical analysis were applied to available data on earthworm of Iran. PMID:26438954

  16. Is carbon sequestration on post mining sites driven by earthworm activity?

    NASA Astrophysics Data System (ADS)

    Frouz, J.; Pizl, V.

    2009-04-01

    Carbon storage was measured in seven types of forest (alder, oak, lime, willow-birch, pine, spruce and larch) about 30 years old developed in on e large post mining site as split plot design. The carbon storage in soil wary substantial and represent 10-100% of carbon storage in aboveground wood biomass. Carbon storage in soil do not show any correlation with litter input but correlate significantly and positively with earthworm abundance, and micromorphological traces of earthworm activity. Field and laboratory microcosm experiment showed that earthworm mediated soil mixing support carbon storage in soil. Detailed study of soil aggregates created by worms and other forces indicated that worm aggregates contain much larger content of POC. This indicate that soil bioturbation by earthworms may significantly increase carbon storage in soil.

  17. FUNCTIONAL CONNECTIONS ARE ESTABLISHED BETWEEN GIANT NERVE FIBERS IN GRAFTED EARTHWORMS

    EPA Science Inventory

    Giant fiber interconnections were examined in successful grafts between two posterior portions of earthworms (Eisenia foetida). Electrophysiological and histological results indicated that cell-specific interanimal connections were formed between the medial giant fibers (MGF) in ...

  18. Glyphosate herbicide affects belowground interactions between earthworms and symbiotic mycorrhizal fungi in a model ecosystem

    NASA Astrophysics Data System (ADS)

    Zaller, Johann G.; Heigl, Florian; Ruess, Liliane; Grabmaier, Andrea

    2014-07-01

    Herbicides containing glyphosate are widely used in agriculture and private gardens, however, surprisingly little is known on potential side effects on non-target soil organisms. In a greenhouse experiment with white clover we investigated, to what extent a globally-used glyphosate herbicide affects interactions between essential soil organisms such as earthworms and arbuscular mycorrhizal fungi (AMF). We found that herbicides significantly decreased root mycorrhization, soil AMF spore biomass, vesicles and propagules. Herbicide application and earthworms increased soil hyphal biomass and tended to reduce soil water infiltration after a simulated heavy rainfall. Herbicide application in interaction with AMF led to slightly heavier but less active earthworms. Leaching of glyphosate after a simulated rainfall was substantial and altered by earthworms and AMF. These sizeable changes provide impetus for more general attention to side-effects of glyphosate-based herbicides on key soil organisms and their associated ecosystem services.

  19. Mercury, cadmium and lead concentrations in different ecophysiological groups of earthworms in forest soils.

    PubMed

    Ernst, Gregor; Zimmermann, Stefan; Christie, Peter; Frey, Beat

    2008-12-01

    Bioaccumulation of Hg, Cd and Pb by eight ecophysiologically distinct earthworm species was studied in 27 polluted and uncontaminated forest soils. Lowest tissue concentrations of Hg and Cd occurred in epigeic Lumbricus rubellus and highest in endogeic Octolasion cyaneum. Soils dominated by Dendrodrilus rubidus possess a high potential of risk of Pb biomagnification for secondary predators. Bioconcentration factors (soil-earthworm) followed the sequence ranked Cd>Hg>Pb. Ordination plots of redundancy analysis were used to compare HM concentrations in earthworm tissues with soil, leaf litter and root concentrations and with soil pH and CEC. Different ecological categories of earthworms are exposed to Hg, Cd and Pb in the topsoil by atmospheric deposition and accumulate them in their bodies. Species differences in HM concentrations largely reflect differences in food selectivity and niche separation. PMID:18400348

  20. The effect of earthworms on copper fractionation of freshly and long-term polluted soils.

    PubMed

    Fujii, Yoshikazu; Kaneko, Nobuhiro

    2009-09-01

    We investigated the effects of earthworm activity on the bioavailability of Cu in soil. The bioavailable fraction was estimated using sequential extraction, and the results of diethylenetriaminepentaacetic acid (DTPA) extraction were analyzed for comparison. Changes in the Cu fraction were compared in Cu-spiked soil (high bioavailability) and long-term polluted field soil (low bioavailability) with approximately equivalent total Cu concentrations. Earthworm activity decreased the bioavailable fraction in the Cu-spiked soil, where earthworm body Cu concentrations did not affect the bioavailable fraction. Soil pH was not a factor in the bioavailability differences between soils with and without earthworms in this study. The bioavailable fraction appears to be more heavily affected by biological and physical mechanisms than by soil pH. The two extraction methods showed different trends; the bioavailable fraction method was better than DTPA extraction, because the former gives clear insight into the aging process of Cu in soil. PMID:19477521

  1. Impact of the earthworm Lumbricus terrestris (L.) on As, Cu, Pb and Zn mobility and speciation in contaminated soils.

    PubMed

    Sizmur, Tom; Palumbo-Roe, Barbara; Watts, Michael J; Hodson, Mark E

    2011-03-01

    To assess the risks that contaminated soils pose to the environment properly a greater understanding of how soil biota influence the mobility of metal(loid)s in soils is required. Lumbricus terrestris L. were incubated in three soils contaminated with As, Cu, Pb and Zn. The concentration and speciation of metal(loid)s in pore waters and the mobility and partitioning in casts were compared with earthworm-free soil. Generally the concentrations of water extractable metal(loid)s in earthworm casts were greater than in earthworm-free soil. The impact of the earthworms on concentration and speciation in pore waters was soil and metal specific and could be explained either by earthworm induced changes in soil pH or soluble organic carbon. The mobilisation of metal(loid)s in the environment by earthworm activity may allow for leaching or uptake into biota. PMID:21185630

  2. Kinetics and spatial distribution of enzymes of carbon, nitrogen and phosphorus cycles in earthworm biopores

    NASA Astrophysics Data System (ADS)

    Hoang Thi Thu, Duyen; Razavi, Bahar S.

    2016-04-01

    Earthworms boost microbial activities and consequently form hotspots in soil. The distribution of enzyme activities inside the earthworm biopores is completely unknown. For the first time, we analyzed enzyme kinetics and visualized enzyme distribution inside and outside biopores by in situ soil zymography. Kinetic parameters (Vmax and Km) of 6 enzymes β-glucosidase (GLU), cellobiohydrolase (CBH), xylanase (XYL), chitinase (NAG), leucine aminopeptidase (LAP) and acid phosphatase (APT) were determined in biopores formed by Lumbricus terrestris L.. The spatial distributions of GLU, NAG and APT become visible via zymograms in comparison between earthworm-inhabited and earthworm-free soil. Zymography showed heterogeneous distribution of hotspots in the rhizosphere and biopores. The hotspot areas were 2.4 to 14 times larger in the biopores than in soil without earthworms. The significantly higher Vmax values for GLU, CBH, XYL, NAG and APT in biopores confirmed the stimulation of enzyme activities by earthworms. For CBH, XYL and NAG, the 2- to 3-fold higher Km values in biopores indicated different enzyme systems with lower substrate affinity compared to control soil. The positive effects of earthworms on Vmax were cancelled by the Km increase for CBH, XYL and NAG at a substrate concentration below 20 μmol g-1 soil. The change of enzyme systems reflected a shift in dominant microbial populations toward species with lower affinity to holo-celluloses and to N-acetylglucosamine, and with higher affinity to proteins as compared to the biopores-free soil. We conclude that earthworm biopores are microbial hotspots with much higher and dense distribution of enzyme activities compared to bulk soil. References Spohn M, Kuzyakov Y. (2014) Spatial and temporal dynamics of hotspots of enzyme activity in soil as affected by living and dead roots - a soil zymography analysis, Plant Soil 379: 67-77. Blagodatskaya, E., Kuzyakov, Y., 2013. Review paper: Active microorganisms in soil

  3. The Impact of Invasive Earthworm Activity on Biopolymer Character of ýDecayed Litter ý

    NASA Astrophysics Data System (ADS)

    Filley, T.; Crow, S.; Johnston, C.; McCormick, M.; Szlavecz, K.

    2007-12-01

    Over the last 400-500 years invasive European earthworm populations have ýmoved steadily into North American forests either previously devoid of ýearthworms or that contained their own native populations. This has profound ýimpacts upon litter decay and soil organic matter dynamics. To determine the ýimpact of earthworm activity on the biopolymer and stable isotope chemistry of ýlitter residues and the nature of organic carbon moved to the soil profile we ýanalyzed tulip poplar leaves from a multi-year addition experiment in open ýsurface decay litter and litter bag decay experiments, as well as the associated ýsoils among forest plots that varied in non-native earthworm density and ýbiomass. The chemical alteration of biopolymers was tracked with FTIR ýspectroscopy, 13C-TMAH thermochemolysis, alkaline CuO extraction, and stable ýisotope mass spectrometry. Earthworm activity resulted in residues and soil ýparticulate organic matter depleted in cuticular aliphatic components and ýpolyphenols but highly enriched in ether-linked lignin with respect to initial litter ýmaterial. Decay in low earthworm abundance plots, as well as all experiments ýwith earthworm-excluding litter bags, resulted in enrichment in cutin aliphatics ýand only minor increases in ether linked lignin phenols which was also reflected ýin the soils below the amendments. Additionally, the stable carbon and nitrogen ýisotope composition of tulip poplar residues became isotopically distinct. The ýresults from litter bag decays were only reflective of the chemistry at sites with ývery low earthworm abundances. ý

  4. Complete mitochondrial genome of a Pheretimoid earthworm Metaphire vulgaris (Oligochaeta: Megascolecidae).

    PubMed

    Zhang, Liangliang; Jiang, Jibao; Dong, Yan; Qiu, Jiangping

    2016-01-01

    We have determined the mitochondrial genome of the first Pheretimoid earthworm, Metaphire vulgaris (Chen, 1930). This mitogenome is 15,061 bp in length containing 37 genes typical of other annelid. All genes are encoded by the same strand, ATP8 is not adjacent to ATP6, all 13 PCGs use ATG as a start codon. These features are consistent with first determined earthworm Lumbricus terrestris, but unusual among animal mtDNAs. PMID:24617491

  5. Emission of Methane by Eudrilus eugeniae and Other Earthworms from Brazil

    PubMed Central

    Depkat-Jakob, Peter S.; Hunger, Sindy; Schulz, Kristin; Brown, George G.; Tsai, Siu M.

    2012-01-01

    Earthworms emit denitrification-derived nitrous oxide and fermentation-derived molecular hydrogen. The present study demonstrated that the earthworm Eudrilus eugeniae, obtained in Brazil, emitted methane. Other worms displayed a lesser or no capacity to emit methane. Gene and transcript analyses of mcrA (encoding the alpha subunit of methyl-CoM reductase) in gut contents of E. eugeniae suggested that Methanosarcinaceae, Methanobacteriaceae, and Methanomicrobiaceae might be associated with this emission. PMID:22344639

  6. Geochemistry and Chemical Weathering in Soils along an Earthworm Invasion Gradient

    NASA Astrophysics Data System (ADS)

    Resner, K.; Yoo, K.; Aufdenkampe, A. K.; Hale, C.; Sebestyen, S. D.

    2010-12-01

    One of the central tenets in geomorphology is that a chemical denudation rate is limited by the total denudation rate, which controls how fast minerals are exposed to reactive environments of the earth’s surface. Though the mineral supply rate has been routinely tied to tectonic uplifts, in soil mantled landscapes, organisms such as earthworms may also significantly contribute to exposing minerals to varying geochemical environments and thus altering chemical denudation rates of the landscapes they inhabit through mineral translocation. In glaciated parts of North America, many forests evolved without native earthworms, since the last glacial retreat, until they were invaded by exotic earthworm species that arrived with agriculture, recreational fishing, and logging. Therefore, an earthworm invasion chronosequence in northern Minnesota--the focus of this ongoing study--provides an ideal natural laboratory to quantitatively study how burrowing organisms, by mixing soils, contribute to chemically denuding the landscapes. We are currently determining the inorganic chemistry of soils along a ~200 meter long transect that includes pre earthworm invasion soils as well as soils populated with several earthworm species with different burrowing habits. Additionally, six soils pits along the transect are densely installed with lysimeters, piezometers, and gas sampling tubes. The soils’ elemental chemistry profiles show that earthworms have significantly relocated minerals vertically, which is consistent with the 210Pb activity profiles determined with gamma spectroscopy. Major elements, depending on their solubility, biological demands, and susceptibility to be complexed with organic matter, respond to the enhanced mixing rates in different ways. To constrain the impacts of earthworm burrowing on chemical denudation, we are also measuring cations, anions, and alkalinity in the water samples collected with the lysimeters and piezometers. Ultimately, the soil and water

  7. Organochlorine pesticide residues in woodcock, soils and earthworms in Louisiana, 1965

    USGS Publications Warehouse

    McLane, M.A.R.; Stickel, L.F.; Newsom, J.D.

    1971-01-01

    Woodcock (Philohela minor), earthworms, and soil samples were collected from January-March 1965, from fields in southeastern Louisiana approximately 3 years after discontinuance of areal treatments with heptachlor in this region. Heptachlor epoxide residues in woodcock averaged 0.42 ppm (dry weight), conspicuously lower than in 1961 and 1962. Residues of DDE in woodcock averaged 3.62 pprn, higher than in birds taken in the same area in 1961-62. Earthworms and soils contained traces of several organochlorine pesticides.

  8. Avoidance of hydrolyzed casein by mice

    PubMed Central

    Field, Kristin L.; Kimball, Bruce A.; Mennella, Julie A.; Beauchamp, Gary K.; Bachmanov, Alexander A.

    2008-01-01

    When casein, a milk protein, is hydrolyzed, it renders human foods that contain it (e.g., hypoallergenic infant formula, cheeses) distasteful to many people. This rejection of hydrolyzed casein (HC)-containing foods has recently been found to also occur in a non-human species (deer, Odocoileus spp.). Identifying other animals that avoid HC would facilitate understanding how and why HC-containing food is often rejected. This study determined whether HC-containing food is avoided by Mus musculus and whether consumption patterns were sensitive to testing conditions, specifically food form (powder, pellet or dough) and food access (ad libitum or 1.5 h/day following 6 h of food deprivation). Diets were offered in two-choice tests that paired an HC-containing food with an intact casein-containing alternative at seven protein concentrations (0%–50% w/w). Five experimental groups were tested under different combinations of food form and food access. Three groups (ad lib/powder, ad lib/pellet, and 1.5 h/pellet) avoided the HC diet starting at the 30% protein level. At the 40% and 50% protein levels, all groups showed strong avoidance of HC. Although testing conditions influenced total caloric intake and body weight gain, avoidance of HC at the highest concentrations was robust to the manipulations in experimental conditions. Our study suggests that mice may be a useful model for understanding the mechanisms of HC rejection. PMID:17900635

  9. Rapid dissemination of Mycobacterium bovis from cattle dung to soil by the earthworm Lumbricus terrestris.

    PubMed

    Barbier, Elodie; Chantemesse, Benoit; Rochelet, Murielle; Fayolle, Léon; Bollache, Loïc; Boschiroli, Maria Laura; Hartmann, Alain

    2016-04-15

    Indirect transmission of Mycobacterium bovis, the causative agent of bovine tuberculosis (bTB), between wildlife and livestock is thought to occur by inhalation or ingestion of environmental substrates contaminated through animal shedding. The role of the soil fauna, such as earthworms, in the circulation of M. bovis from contaminated animal feces is of interest in the epidemiology of bTB. The objective of this study was to assess the impact of earthworm activity on M. bovis transfer from animal dung to castings and the surrounding soil. For this purpose, microcosms of soil containing the anecic earthworms Lumbricus terrestris were prepared and covered with cattle feces spiked with the M. bovis BCG strain Pasteur to carry out two separate experiments. The dissemination, the gut carriage and the excretion of M. bovis were all monitored using a specific qPCR-based assay. Our results showed that the earthworm L. terrestris was able to rapidly disseminate M. bovis from the contaminated cattle feces to the surrounding soil through casting egestion. Moreover, contaminated earthworms were shown to shed the bacteria for 4 days when transferred to a M. bovis-free soil. This study highlights for the first time the possible role of earthworms in the dissemination and the persistence of M. bovis in soils within bTB endemic areas. PMID:27016750

  10. New methodology for determining chronic effects on the earthworm, Eisenia foetida

    SciTech Connect

    Garvey, N.A.

    1994-12-31

    The study design incorporates the exposure of two generations of earthworms, Eisenia foetida, and includes the sensitive developmental stage following emergence from the cocoon. Adult earthworms (F{sub 0} generation) were exposed to nominal concentrations of 16, 31, 63, 125 and 250 mg A.I. copper sulfate/kg in composted cattle manure for 14 days. Cocoons were collected six times throughout the F{sub 0} generation exposure. Upon collection, individual cocoons were weighed and transferred to separate aliquots of treated and untreated exposure manure and were allowed to hatch. Hatched F{sub 1} earthworms were allowed to mature for 21 days before being counted and individually weighed. Parameters monitored and statistically analyzed were: F{sub 0} burrowing time at initiation, F{sub 0} survival following 7 and 14 days of exposure, cocoon production, cocoon weight, cocoon viability, number and weight of F{sub 1} earthworms at 21 days post-hatch. The following endpoints clearly demonstrated chronic effects in at least the highest exposure concentration: cocoon production, mean cocoon weight, sum of cocoon weights, cocoon viability, number and weight of surviving earthworms (F{sub 1}) at 21 days post-hatch, mean and total earthworm (F{sub 1}) biomass at 21 days post-hatch. Although the acute LC50 of copper sulfate to Eisenia foetida was previously determined to be 1,100 {+-} 380 mg copper sulfate/kg, this methodology indicates that chronic toxicity effects can be observed at substantially lower concentrations.

  11. Radiocesium ([sup 137]Cs) from the Chernobyl reactor in Eurasian woodcock and earthworms in Norway

    SciTech Connect

    Kalas, J.A. ); Bretten, S.; Njastad, O. ); Byrkjedal, I. )

    1994-01-01

    To understand the ecological effects of the Chernobyl reactor accident, we investigated radiocesium ([sup 137]Cs) levels in Eurasian woodcock (Scolopax rusticola), earthworms (Lambricidae), litter (dead organic materials lying on the ground), humus (beneath litter 2 cm deep), and mineral soil samples (3-6 cm deep) from a heavily effected (20-60 kBq/m[sup 2][1 Bq = 1 nuclear fission/sec]) area in Norway. The highest concentrations measured in earthworms (1988 median = 142 Bq/Kg) and woodcock (1986 median = 730 Bq/kg) for human food (600 Bq/kg fresh mass) only were found in woodcock during 1986. Radiocesium concentrations decreased (P < 0.001) in earthworms (40%) and woodcock (95%) from 1986 to 1990. There was no reduction in total radiocesium in soil over the same period. The relatively high radiocesium concentrations in woodcock during 1986 and the decreasing radiocesium ratio in woodcock to earthworms during the first years following fallout could have been caused by woodcock ingesting abiotic radiocesium with earthworms. The decrease in radiocesium in woodcock and earthworms during the study (1986-90) probably resulted from decreasing bioavailability of radiocesium during the first years after fallout rather than by radiocesium disappearing from the ecosystem. 38 refs., 3 figs., 2 tabs.

  12. Effects of soil properties on copper toxicity to earthworm Eisenia fetida in 15 Chinese soils.

    PubMed

    Duan, Xiongwei; Xu, Meng; Zhou, Youya; Yan, Zengguang; Du, Yanli; Zhang, Lu; Zhang, Chaoyan; Bai, Liping; Nie, Jing; Chen, Guikui; Li, Fasheng

    2016-02-01

    The bioavailability and toxicity of metals in soil are influenced by a variety of soil properties, and this principle should be recognized in establishing soil environmental quality criteria. In the present study, the uptake and toxicity of Cu to the earthworm Eisenia fetida in 15 Chinese soils with various soil properties were investigated, and regression models for predicting Cu toxicity across soils were developed. The results showed that earthworm survival and body weight change were less sensitive to Cu than earthworm cocoon production. The soil Cu-based median effective concentrations (EC50s) for earthworm cocoon production varied from 27.7 to 383.7 mg kg(-1) among 15 Chinese soils, representing approximately 14-fold variation. Soil cation exchange capacity and organic carbon content were identified as key factors controlling Cu toxicity to earthworm cocoon production, and simple and multiple regression models were developed for predicting Cu toxicity across soils. Tissue Cu-based EC50s for earthworm cocoon production were also calculated and varied from 15.5 to 62.5 mg kg(-1) (4-fold variation). Compared to the soil Cu-based EC50s for cocoon production, the tissue Cu-based EC50s had less variation among soils, indicating that metals in tissue were more relevant to toxicity than metals in soil and hence represented better measurements of bioavailability. PMID:26688255

  13. Complete mitochondrial genome of four pheretimoid earthworms (Clitellata: Oligochaeta) and their phylogenetic reconstruction.

    PubMed

    Zhang, Liangliang; Jiang, Jibao; Dong, Yan; Qiu, Jiangping

    2015-12-15

    Among oligochaetes, the Pheretima complex within the Megascolecidae is a major earthworm group. Recently, however, the systematics of the Pheretima complex based on morphology are challenged by molecular studies. Since little comparative analysis of earthworm complete mitochondrial genomes has been reported yet, we sequenced mitogenomes of four pheretimoid earthworm species to explore their phylogenetic relationships. The general earthworm genomic features are also found in four earthworms: all genes transcribed from the same strand, the same initiation codon ATG for each PCGs, and conserved structures of RNA genes. Interestingly we find an extra potential tRNA-leucine (CUN) in Amynthas longisiphonus. The earthworm mitochondrial ATP8 exhibits the highest evolutionary rate, while the gene CO1 evolves slowest. Phylogenetic analysis based on protein-coding genes (PCGs) strongly supports the monophyly of the Clitellata, Hirudinea, Oligochaeta, Megascolecidae and Pheretima complex. Our analysis, however, reveals non-monophyly within the genara Amynthas and Metaphire. Thus the generic divisions based on morphology in the Pheretima complex should be reconsidered. PMID:26291739

  14. Impact of organic rich diet on gut enzymes, microbes and biomass of earthworm, Eudrilus eugienea.

    PubMed

    Sumathi, G; Thaddeus, Arockiam

    2013-05-01

    Vermitechnology provides scope and opportunities in the field of Biotechnology. The sudden decline in earthworm biomass may mainly be due to the over use of chemicals. Steps had been taken to enhance the production of biomass of earthworms by providing organic wastes rich in major organic constituents such as cereals, pulses and skin of chick. Earthworms (Eudrilus eugienea) were fed with organic constituents individually, and in combination of organic rich diet. The biomass of the earthworm was steadily increasing in the individual treatment was found when fed with organic rich diet at 10, 20 and 30 days respectively 09.987, 13.569 and 18.212. The bacterial counts in the gut of earthworms were 543 x 10(5) CFU ml(-1). The bacteria identified were Bacillus spp., Lactobacillus spp and Flavobacterium spp. Enzymes screened in the gut were amylase, endoglucanase, cellulase, sucrase and protease. From the present investigation, it was found that the organic rich diet is the ideal medium in which the biomass of earthworms are high, their enzymatic activity was also high with variety of microbes which will enhance the efficiency of the soil. PMID:24617136

  15. Earthworms dilong: ancient, inexpensive, noncontroversial models may help clarify approaches to integrated medicine emphasizing neuroimmune systems.

    PubMed

    Cooper, Edwin L; Balamurugan, Mariappan; Huang, Chih-Yang; Tsao, Clara R; Heredia, Jesus; Tommaseo-Ponzetta, Mila; Paoletti, Maurizio G

    2012-01-01

    Earthworms have provided ancient cultures with food and sources of medicinal cures. Ayurveda, traditional Chinese medicine (TCM), and practices in Japan, Vietnam, and Korea have focused first on earthworms as sources of food. Gradually fostering an approach to potential beneficial healing properties, there are renewed efforts through bioprospecting and evidence-based research to understand by means of rigorous investigations the mechanisms of action whether earthworms are used as food and/or as sources of potential medicinal products. Focusing on earthworms grew by serendipity from an extensive analysis of the earthworm's innate immune system. Their immune systems are replete with leukocytes and humoral products that exert credible health benefits. Their emerging functions with respect to evolution of innate immunity have long been superseded by their well-known ecological role in soil conservation. Earthworms as inexpensive, noncontroversial animal models (without ethical concerns) are not vectors of disease do not harbor parasites that threaten humans nor are they annoying pests. By recognizing their numerous ecological, environmental, and biomedical roles, substantiated by inexpensive and more comprehensive investigations, we will become more aware of their undiscovered beneficial properties. PMID:22888362

  16. Invasive earthworms interact with abiotic conditions to influence the invasion of common buckthorn (Rhamnus cathartica).

    PubMed

    Roth, Alexander M; Whitfeld, Timothy J S; Lodge, Alexandra G; Eisenhauer, Nico; Frelich, Lee E; Reich, Peter B

    2015-05-01

    Common buckthorn (Rhamnus cathartica L.) is one of the most abundant and ecologically harmful non-native plants in forests of the Upper Midwest United States. At the same time, European earthworms are invading previously glaciated areas in this region, with largely anecdotal evidence suggesting they compound the negative effects of buckthorn and influence the invasibility of these forests. Germination and seedling establishment are important control points for colonization by any species, and manipulation of the conditions influencing these life history stages may provide insight into why invasive species are successful in some environments and not others. Using a greenhouse microcosm experiment, we examined the effects of important biotic and abiotic factors on the germination and seedling establishment of common buckthorn. We manipulated light levels, leaf litter depth and earthworm presence to investigate the independent and interactive effects of these treatments on buckthorn establishment. We found that light and leaf litter depth were significant predictors of buckthorn germination but that the presence of earthworms was the most important factor; earthworms interacted with light and leaf litter to increase the number and biomass of buckthorn across all treatments. Path analysis suggested both direct and moisture-mediated indirect mechanisms controlled these processes. The results suggest that the action of earthworms may provide a pathway through which buckthorn invades forests of the Upper Midwest United States. Hence, researchers and managers should consider co-invasion of plants and earthworms when investigating invasibility and creating preemptive or post-invasion management plans. PMID:25481818

  17. Enantioselective kinetics of α-hexachlorocyclohexane in earthworm (Eisenia fedtia) and forest soil.

    PubMed

    Zhou, Gaoxin; Liu, Donghui; Ma, Ruixue; Li, Jindong; Sun, Mingjing; Zhou, Zhiqiang; Wang, Peng

    2012-08-01

    The enantioselective bioaccumulation and elimination behaviors of α-hexachlorocyclohexane (α-HCH) enantiomers in earthworm and soil were investigated by chiral gas chromatography. Enantiomer fraction values were calculated as indicators of the enantioselectivity. The mature earthworms were exposed to 0.10 µg g(-1)(wwt) (0.14 µg g(-1)(dwt)) spiked soil continuously for the bioaccumulation, and the elimination was conducted after an enrichment period in the soil. The results showed that both the bioaccumulation and elimination processes followed monophasic kinetics, body residues of α-HCH in earthworm increased to high level at the fifth day, and enantioselectivity was found in the bioaccumulation process with the rate constant (k) of 0.80 d(-1) for (+)-α-HCH and 0.74 d(-1) for (-)-α-HCH. The half life (t(1/2)) of the enantiomers obtained in the elimination process was within one day. The bioaccumulation factors of steady state of α-HCH enantiomers were 2.82 for (+)-α-HCH and 2.75 for (-)-α-HCH. The enantiomer fractions of earthworm and soil obviously below 0.5 during uptake and elimination processes indicate significant enantioselectivity and preferential depuration of (+)-α-HCH in earthworm. However, earthworms do not have a great capacity for getting rid of α-HCH in polluted soil shown by a contradistinctive experiment. PMID:22674802

  18. The influence of earthworms on nutrient dynamics during the process of vermicomposting.

    PubMed

    Domínguez, Jorge; Gómez-Brandón, María

    2013-08-01

    In the present study the potential of the earthworm Eisenia andrei to modify chemical and microbiological properties, with a special focus on the nutrient content of fresh organic matter, was evaluated during 16 weeks of vermicomposting of cattle manure and sewage sludge. Samples were periodically collected in order to determine the changes in inorganic nitrogen (N), in total microbial biomass and activity, as well as in the total and available content of macro- and micronutrients. An optimal moisture level, ranging from 75% to 88%, was maintained throughout the process. The content of organic matter decreased over time, but no changes were found in this parameter as a result of earthworm activity. The carbon/N ratio rapidly decreased, but only in the manure, reflecting rapid decomposition and mineralisation of the organic matter by the earthworms. An increase in N mineralisation was also attributable to the presence of earthworms, although in the manure this effect was hardly detectable before the eighth week of vermicomposting. Earthworm activity also enhanced the total content of potassium, calcium and iron together with an increase in the availability of phosphorus and zinc. We did not detect a significant earthworm effect on microbial respiration, but their activity increased greatly microbial biomass nitrogen in sewage sludge. PMID:23831778

  19. Earthworms Dilong: Ancient, Inexpensive, Noncontroversial Models May Help Clarify Approaches to Integrated Medicine Emphasizing Neuroimmune Systems

    PubMed Central

    Cooper, Edwin L.; Balamurugan, Mariappan; Huang, Chih-Yang; Tsao, Clara R.; Heredia, Jesus; Tommaseo-Ponzetta, Mila; Paoletti, Maurizio G.

    2012-01-01

    Earthworms have provided ancient cultures with food and sources of medicinal cures. Ayurveda, traditional Chinese medicine (TCM), and practices in Japan, Vietnam, and Korea have focused first on earthworms as sources of food. Gradually fostering an approach to potential beneficial healing properties, there are renewed efforts through bioprospecting and evidence-based research to understand by means of rigorous investigations the mechanisms of action whether earthworms are used as food and/or as sources of potential medicinal products. Focusing on earthworms grew by serendipity from an extensive analysis of the earthworm's innate immune system. Their immune systems are replete with leukocytes and humoral products that exert credible health benefits. Their emerging functions with respect to evolution of innate immunity have long been superseded by their well-known ecological role in soil conservation. Earthworms as inexpensive, noncontroversial animal models (without ethical concerns) are not vectors of disease do not harbor parasites that threaten humans nor are they annoying pests. By recognizing their numerous ecological, environmental, and biomedical roles, substantiated by inexpensive and more comprehensive investigations, we will become more aware of their undiscovered beneficial properties. PMID:22888362

  20. Influence of plant-earthworm interactions on SOM chemistry and p,p'-DDE bioaccumulation.

    PubMed

    Kelsey, Jason W; Slizovskiy, Ilya B; Petriello, Michael C; Butler, Kelly L

    2011-05-01

    Laboratory experiments assessed how bioaccumulation of weathered p,p'-DDE from soil and humic acid (HA) chemistry are affected by interactions between the plants Cucurbita pepo ssp. pepo and ssp. ovifera and the earthworms Eisenia fetida, Lumbricus terrestris, and Apporectodea caliginosa. Total organochlorine phytoextraction by ssp. pepo increased at least 25% in the presence of any of the earthworm species (relative to plants grown in isolation). Uptake of the compound by ssp. ovifera was unaffected by earthworms. Plants influenced earthworm bioaccumulation as well. When combined with pepo, p,p'-DDE levels in E. fetida decreased by 50%, whereas, in the presence of ovifera, bioconcentration by L. terrestris increased by more than 2-fold. Spectral analysis indicated a decrease in hydrophobicity of HA in each of the soils in which both pepo and earthworms were present. However, HA chemistry from ovifera treatments was largely unaffected by earthworms. Risk assessments of contaminated soils should account for species interactions, and SOM chemistry may be a useful indictor of pollutant bioaccumulation. PMID:21421253

  1. Self-Assemblage and Quorum in the Earthworm Eisenia fetida (Oligochaete, Lumbricidae)

    PubMed Central

    Zirbes, Lara; Brostaux, Yves; Mescher, Mark; Jason, Maxime; Haubruge, Eric; Deneubourg, Jean-Louis

    2012-01-01

    Despite their ubiquity and ecological significance in temperate ecosystems, the behavioural ecology of earthworms is not well described. This study examines the mechanisms that govern aggregation behaviour specially the tendency of individuals to leave or join groups in the compost earthworm Eisenia fetida, a species with considerable economic importance, especially in waste management applications. Through behavioural assays combined with mathematical modelling, we provide the first evidence of self-assembled social structures in earthworms and describe key mechanisms involved in cluster formation. We found that the probability of an individual joining a group increased with group size, while the probability of leaving decreased. Moreover, attraction to groups located at a distance was observed, suggesting a role for volatile cues in cluster formation. The size of earthworm clusters appears to be a key factor determining the stability of the group. These findings enhance our understanding of intra-specific interactions in earthworms and have potential implications for extraction and collection of earthworms in vermicomposting processes. PMID:22396774

  2. Persistence in earthworms and potential hazards to birds of soil applied DDT, dieldrin, and heptachlor

    USGS Publications Warehouse

    Beyer, W.N.; Gish, C.D.

    1980-01-01

    (1) DDT, dieldrin, and heptachlor were each applied to separate replicate plots in a hay field at 0.6, 2.2, or 9.0 kg/ha. For 11 yr thereafter, soil and earthworms were analysed for residues. (2) The average ratios of residues in earthworms (dry weight) to residues in soil (dry weight) were: total DDT, 5; dieldrin, 8; and heptachlor epoxide, 10. The average time for the initial residues in soil to be reduced by 50% were: total DDT, 3.2 yr; dieldrin, 5.1 yr; and heptachlor epoxide, 3.2 yr. The corresponding times for residues in earthworms were: total DDT, 3.2 yr; dieldrin, 2.6 yr; and heptachlor epoxide, 3.0 yr. (3) DDE was most persistent, and in plots treated at 9.0 kg/ha its concentration remained constant at about 0.4 ppm in soil and about 7 ppm in earthworms. (4) When applied at 9.0 kg/ha, DDT accumulated in earthworms to concentrations (32 ppm) which laboratory studies have shown to be hazardous to some sensitive bird species. When heptachlor was applied at 2.2 or 9.0 kg/ha, heptachlor epoxide in earthworms reached concentrations (8 ppm) potentially hazardous to woodcock. Dieldrin remained at potentially hazardous concentrations (8 ppm) for 3 yr in plots treated with 2.2 kg/ha and for 11 yr in plots treated with 9.0 kg/ha.

  3. Soil bioturbation by earthworms and plant roots- mechanical and energetic considerations

    NASA Astrophysics Data System (ADS)

    Ruiz, S.; Or, D.; Schymanski, S. J.

    2014-12-01

    Soil structure is a key factor shaping hydrological and ecological functions including water storage, deep recharge and plant growth. Compaction adversely impacts soil ecosystem services over extended periods (years to decades) until structure and functionality are restored. An important class of soil structural restoration processes are related to biomechanical activity associated with borrowing of earthworms and root proliferation in impacted soils. This study employs a new biomechanical model to estimate stresses required for earthworm and plant root bioturbation under different conditions and the mechanical energy required. We consider steady state plastic cavity expansion to determine burrowing pressures of earthworms and plant roots as linked with models for cone penetration required for initial burrowing into soil volumes. We use earthworm physical and ecological parameters (e.g., population density, burrowing rate, and burrowing behavior) to convert mechanical deformation to estimation of energy and soil organic carbon (energy source for earthworms). Results illustrate a reduction in strain energy with increasing water content and trade-offs between pressure and energy investment for various root and earthworm geometries and soil hydration. The study provides a quantitative framework for estimating energy costs of bioturbation in terms of soil organic carbon or plant assimilates and delineates mechanical and hydration conditions that promote or constrain such activities.

  4. Value contamination avoidance devices

    NASA Technical Reports Server (NTRS)

    Endicott, D. L.

    1975-01-01

    Mechanical redesign methods were used to minimize contamination damage of conventional fluid components and a contamination separator device was developed for long term reusable space vehicles. These were incorporated into an existing 50.8 mm poppet valve and tested for damage tolerance in a full size open loop flow system with gaseous and liquid nitrogen. Cyclic and steady flow conditions were tested with particles of 125 to 420 micrometers aluminum oxide dispersed in the test fluids. Nonflow life tests (100,000 cycles) were made with two valve configurations in gaseous hydrogen. The redesigned valve had an acceptable cycle life and improved tolerance to contamination damage when the primary sealing surfaces were coated with thin coatings of hard plastic (Teflon S and Kynar). Analytical studies and flow testing were completed of four different versions of the separator. overall separation efficiencies in the 55-90% range were measured with these non-optimum configurations.

  5. CAT altitude avoidance system

    NASA Technical Reports Server (NTRS)

    Gary, B. L. (Inventor)

    1982-01-01

    A method and apparatus are provided for indicating the altitude of the tropopause or of an inversion layer wherein clear air turbulence (CAT) may occur, and the likely severity of any such CAT, includes directing a passive microwave radiometer on the aircraft at different angles with respect to the horizon. The microwave radiation measured at a frequency of about 55 GHz represents the temperature of the air at an ""average'' range of about 3 kilometers, so that the sine of the angle of the radiometer times 3 kilometers equals the approximate altitude of the air whose temperature is measured. A plot of altitude (with respect to the aircraft) versus temperature of the air at that altitude, can indicate when an inversion layer is present and can indicate the altitude of the tropopause or of such an inversion layer. The plot can also indicate the severity of any CAT in an inversion layer. If CAT has been detected in the general area, then the aircraft can be flown at an altitude to avoid the tropopause or inversion layer.

  6. Testing Honey Bees' Avoidance of Predators

    ERIC Educational Resources Information Center

    Robinson, Jesse Wade; Nieh, James C.; Goodale, Eben

    2012-01-01

    Many high school science students do not encounter opportunities for authentic science inquiry in their formal coursework. Ecological field studies can provide such opportunities. The purpose of this project was to teach students about the process of science by designing and conducting experiments on whether and how honey bees (Apis mellifera)…

  7. Earthworm invasion as the driving force behind plant invasion and community change in northeastern North American forests.

    PubMed

    Nuzzo, Victoria A; Maerz, John C; Blossey, Bernd

    2009-08-01

    Identification of factors that drive changes in plant community structure and contribute to decline and endangerment of native plant species is essential to the development of appropriate management strategies. Introduced species are assumed to be driving causes of shifts in native plant communities, but unequivocal evidence supporting this view is frequently lacking. We measured native vegetation, non-native earthworm biomass, and leaf-litter volume in 15 forests in the presence and absence of 3 non-native plant species (Microstegium vimineum, Alliaria petiolata, Berberis thunbergii) to assess the general impact of non-native plant and earthworm invasions on native plant communities in northeastern United States. Non-native plant cover was positively correlated with total native plant cover and non-native earthworm biomass. Earthworm biomass was negatively associated with cover of native woody and most herbaceous plants and with litter volume. Graminoid cover was positively associated with non-native earthworm biomass and non-native plant cover. These earthworm-associated responses were detected at all sites despite differences in earthworm species and abundance, composition of the native plant community, identity of invasive plant species, and geographic region. These patterns suggest earthworm invasion, rather than non-native plant invasion, is the driving force behind changes in forest plant communities in northeastern North America, including declines in native plant species, and earthworm invasions appear to facilitate plant invasions in these forests. Thus, a focus on management of invasive plant species may be insufficient to protect northeastern forest understory species. PMID:19236448

  8. Earthworms and priming of soil organic matter - The impact of food sources, food preferences and fauna - microbiota interactions

    NASA Astrophysics Data System (ADS)

    Potthoff, Martin; Wichern, Florian; Dyckmans, Jens; Joergensen, Rainer Georg

    2016-04-01

    Earthworms deeply interact with the processes of soil organic matter turnover in soil. Stabilization of carbon by soil aggregation and in the humus fraction of SOM are well known processes related to earthworm activity and burrowing. However, recent research on priming effects showed inconsistent effects for the impact of earthworm activity. Endogeic earthworms can induce apparent as well as true positive priming effects. The main finding is almost always that earthworm increase the CO2 production from soil. The sources of this carbon release can vary and seem to depend on a complex interaction of quantity and quality of available carbon sources including added substrates like straw or other compounds, food preferences and feeding behavior of earthworms, and soil properties. Referring to recent studies on earthworm effects on soil carbon storage and release (mainly Eck et al. 2015 Priming effects of Aporrectodea caliginosa on young rhizodeposits and old soil organic matter following wheat straw addition, European Journal of Soil Biology 70:38-45; Zareitalabad et al. 2010 Decomposition of 15N-labelled maize leaves in soil affected by endogeic geophagous Aporrectodea caliginosa, Soil Biology and Biochemistry 42(2):276-282; and Potthoff et al. 2001 Short-term effects of earthworm activity and straw amendment on the microbial C and N turnover in a remoistened arable soil after summer drought, Soil Biology and Biochemistry 33(4):583-591) we summaries the knowledge on earthworms and priming and come up with a conceptual approach and further research needs.

  9. Further records of non-cryptic New Zealand earthworms

    PubMed Central

    Blakemore, Robert

    2011-01-01

    Abstract Current descriptions add natives Aporodrilus aotea sp. n., Aporodrilus ponga sp. n. and Notoscolex repanga sp. n., plus new exotic records to the numbers of megadrile earthworms known from New Zealand, which are now raised from 193 to 222 species in five families, viz: Acanthodrilidae, Octochaetidae and Megascolecidae, plus Lumbricidae and Glossoscolecidae for exotics. Overlooked spermathecal diverticula have been located for Notoscolex equestris Benham, 1942 and for Megascolex animae Lee, 1959 and non-tubular prostrates were misconstrued as tubular in Megascolides tasmani Lee, 1959. Of these latter three species, a lectotype is designated for Notoscolex equestris and holotypes of the other two are briefly redescribed. Whereas Megascolides tasmani now belongs in Notoscolex Fletcher, 1887 and Megascolides animae belongs in Anisochaeta Beddard, 1890, further lack of dorsal pores in Notoscolex equestris as with Notoscolex esculentus (Benham, 1904) and Notoscolex mortenseni (Michaelsen, 1924) newly qualifies all three as additional combs. novae in primarily Tasmanian genus Aporodrilus Blakemore, 2000. PMID:22303118

  10. Earthworms newly from Mongolia (Oligochaeta, Lumbricidae, Eisenia).

    PubMed

    Blakemore, Robert J

    2013-01-01

    Two new megadrile earthworms from the steppes, the first species wholly from Outer Mongolia, are ascribed to the partially parthenogenetic Eisenia nordenskioldi (Eisen, 1879) species-complex. Taxonomic justification of sympatric Eisenia nordenskioldi mongol and Eisenia nordenskioldi onon ssp. n. are supported by mtDNA COI barcodes. The unreliability of molecular differentiation based on voucher names compared to definitive types is again demonstrated, as pertains to the ultimate Eisenia andrei Bouché, 1972 synonym of the Eisenia fetida (Savigny, 1826) sibling species-complex composed of more than a dozen prior names. Similar species described from Northeast China [formerly Manchuria] and North Korea are briefly considered, albeit they are intermittently held in synonymy of cosmopolitan Aporrectodea rosea (Savigny, 1826) along with many other taxa including some exotic lumbricids initially found in India. Japanese and North American lumbricids are also mentioned. Distributions are discussed and an annotated checklist of all nine Siberian/sub-arctic Eisenia nordenskioldi ssp. is appended. PMID:23798894

  11. Acute toxicity of virgin and used engine oil enriched with copper nano particles in the earthworm

    NASA Astrophysics Data System (ADS)

    Khodabandeh, M.; Koohi, M. K.; Roshani, A.; Shahroziyan, E.; Badri, B.; Pourfallah, A.; Shams, Gh; Hobbenaghi, R.; Sadeghi-Hashjin, G.

    2011-07-01

    In spite of development of nanotechnology and creation of new opportunities for industry, new applications and products initiated by this technology may cause harmful effects on human health and environment. Unfortunately, there is no sufficient information on the harmful effects caused by application of some nano materials; the current knowledge in this field is limited solely to the nano particles but not the final products. Nano cupper particles, as one of the common materials produced in industrial scale is widely used as additives into engine oil to reduce friction and improve lubrication. However, the difference between the effects of virgin and used conventional engine oil (CEO) and the engine oil containing cupper nano particles (NEO) on the environment is not known. Earthworm, as a one of the species which could live and survive in different sorts of earth and has a certain role in protecting the soil structure and fertility, was used in this experiment. In accordance with the recommended method of OECD.1984, Filter Paper test in 24 and 48 h based on 8 concentrations in the range of 3×10-3 - 24×10-3 ml/cm2 and Artificial Soil test in 7 and 14 days based on 7 concentrations in the range of 0.1 mg/kg - 100 g/kg were carried out to study earthworms in terms of lifetime (LC50), morphology and pathology. It was shown that the 48 h LC50 for virgin CEO, virgin NEO, used CEO(8000 km) and used NEO (8000 km) were 6×10-3, 23×10-3, 24×10-3 and 16×10-3 ml/cm2 respectively. Furthermore, 14-day LC50 in artificial soil for all cases were above 100 g/kg. It is concluded that virgin CEO is more toxic than virgin NEO. Meanwhile, the CEO shows significant reduction in toxicity after consumption and the used NEO shows more toxicity in comparison to virgin product. It seems that more investigations on the effects of final products specifically after consumption is necessary because the products after consumption have the most contact with environment and subsequently

  12. MEST- avoid next extinction

    NASA Astrophysics Data System (ADS)

    Cao, Dayong

    2012-11-01

    Asteroid 2011 AG5 will impact on Earth in 2040. (See Donald K. Yoemans, ``Asteroid 2011 AG5 - A Reality Check,'' NASA-JPL, 2012) In 2011, The author say: the dark hole will take the dark comet to impact our solar system in 20 years, and give a systemic model between the sun and its companion-dark hole to explain why were there periodicity mass extinction on earth. (see Dayong Cao, BAPS.2011.CAL.C1.7, BAPS.2011.DFD.LA.24, BAPS.2012.APR.K1.78 and BAPS.2011.APR.K1.17) The dark Asteroid 2011 AG5 (as a dark comet) is made of the dark matter which has a space-time (as frequence-amplitude square) center- a different systemic model from solar systemic model. It can asborb the space-time and wave. So it is ``dark.'' When many dark matters hit on our earth, they can break our atom structure and our genetic code to trigger the Mass Extinction. In our experiments, consciousness can change the systematic model and code by a life-informational technology. So it can change the output signals of the solar cell. (see Dayong Cao, BAPS.2011.MAR.C1.286 and BAPS.2012.MAR.P33.14) So we will develop the genetic code of lives to evolution and sublimation, will use the dark matter to change the systemic model between dark hole and sun and will avoid next extinction.

  13. Collision avoidance sensor skin

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The objective was to totally eliminate the possibility of a robot (or any mechanism for that matter) inducing a collision in space operations. We were particularly concerned that human beings were safe under all circumstances. This was apparently accomplished, and it is shown that GSFC has a system that is ready for space qualification and flight. However, it soon became apparent that much more could be accomplished with this technology. Payloads could be made invulnerable to collision avoidance and the blind spots behind them eliminated. This could be accomplished by a simple, non-imaging set of 'Capaciflector' sensors on each payload. It also is evident that this system could be used to align and dock the system with a wide margin of safety. Throughout, lighting problems could be ignored, and unexpected events and modeling errors taken in stride. At the same time, computational requirements would be reduced. This can be done in a simple, rugged, reliable manner that will not disturb the form factor of space systems. It will be practical for space applications. The lab experiments indicate we are well on the way to accomplishing this. Still, the research trail goes deeper. It now appears that the sensors can be extended to end effectors to provide precontact information and make robot docking (or any docking connection) very smooth, with minimal loads impacted back into the mating structures. This type of ability would be a major step forward in basic control techniques in space. There are, however, baseline and restructuring issues to be tackled. The payloads must get power and signals to them from the robot or from the astronaut servicing tool. This requires a standard electromechanical interface. Any of several could be used. The GSFC prototype shown in this presentation is a good one. Sensors with their attendant electronics must be added to the payloads, end effectors, and robot arms and integrated into the system.

  14. Can Earthworm "mix up" Soil Carbon Budgets in Temperate Forests Under Elevated Carbon Dioxide?

    NASA Astrophysics Data System (ADS)

    Sánchez-de León, Y.; González-Meler, M.; Sturchio, N. C.; Wise, D. H.; Norby, R. J.

    2008-12-01

    The effects of global change on earthworms and their associated feedbacks on soil and ecosystem processes have been largely overlooked. We studied how the responses of a temperate deciduous forest to elevated carbon dioxide atmospheric concentrations (e[CO2]) influence earthworms and the soil processes affected by them. Our objectives were to: i) identify soil layers of active soil mixing under e[CO2] and current carbon dioxide atmospheric concentrations (c[CO2]) using fallout cesium (137Cs), ii) study how e[CO2] affects earthworm populations, iii) understand the relationship between soil mixing and earthworms at our study site, and iv) identify the implications of earthworm-mediated soil mixing for the carbon budget of a temperate forest. To study soil mixing, we measured vertical 137Cs activity in soil cores (0-24 cm depth) collected in replicated e[CO2] and c[CO2] sweetgum (Liquidambar styraciflua) plots (n = 2) in a Free Air CO2 Enrichment (FACE) ecosystem experiment at Oak Ridge National Laboratory. We measured earthworm density and fresh weight in the plots in areas adjacent to where soil cores were taken. Preliminary results on the vertical distribution of 137Cs in the c[CO2] treatments showed t