Science.gov

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 earthworms and springtails: defining the minimum exposure time to observe a significant response.

    PubMed

    Natal-da-Luz, Tiago; Amorim, Mónica J B; Römbke, Jörg; Sousa, José Paulo

    2008-10-01

    Based on the ability of organisms to avoid contaminated soils, avoidance tests have a great potential as early screening tools in lower tier levels of ERA schemes. Aiming at their standardization, the definition of the minimum exposure time necessary to observe an avoidance response to a contaminant is needed. To fill this gap, avoidance tests with earthworms (Eisenia andrei) and springtails (Folsomia candida), comparing distinct time periods (from 1-7 to 1-14 days, respectively), were performed using the artificial OECD soil and reference chemicals for each test organism. Results showed that for both organisms a clear response within 24 h of exposure can be obtained. This rapid response enhances the utility of the test for "on site" analysis to evaluate contaminated sites. PMID:18006058

  4. 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. ...

  5. 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

  6. Escape and avoidance learning in the earthworm Eisenia hortensis

    PubMed Central

    Ferrara, Nicole C.; Blaker, Amanda L.; Giddings, Charisa E.

    2014-01-01

    Interest in instrumental learning in earthworms dates back to 1912 when Yerkes concluded that they can learn a spatial discrimination in a T-maze. Rosenkoetter and Boice determined in the 1970s that the “learning” that Yerkes observed was probably chemotaxis and not learning at all. We examined a different form of instrumental learning: the ability to learn both to escape and to avoid an aversive stimulus. Freely moving “master” worms could turn off an aversive white light by increasing their movement; the behavior of yoked controls had no effect on the light. We demonstrate that in as few as 12 trials the behavior of the master worms comes under the control of this contingency. PMID:24498578

  7. 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.

  8. 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

  9. 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.

  10. 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

  11. 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

  12. Genotoxicity assessment of cobalt chloride in Eisenia hortensis earthworms coelomocytes by comet assay and micronucleus test.

    PubMed

    Ci?erci, ?brahim Hakk?; Ali, Muhammad Muddassir; Kayg?s?z, ?öhret Yüksek; Liman, Recep

    2016-02-01

    Cobalt and its different compounds are extensively used worldwide and considered as possible environmental pollutant. Earthworms are useful model organism and its different species are used to monitor soil pollution. No study has been found to detect cobalt chloride (CoCl2) genotoxicity in earthworms. So, current study aimed to evaluate CoCl2 induced genotoxicity in Eisenia hortensis earthworms coelomocytes by alkaline comet assay (CA) and micronucleus (MN) test. The earthworms (n = 10 for each group) were exposed to different series of CoCl2 concentrations (100 ppm, 200 ppm, 300 ppm, 400 ppm, 500 ppm, 600 ppm) to find LD50. The LD50 for CoCl2 was found at 226 ppm. Then, doses of LD50/2, LD50 and 2XLD50 for 48 h were used. CA and MN demonstrated the significant increase (P < 0.05) in DNA damage and chromosomal aberrations. Dose dependent relationship was found. Highest DNA damage and chromosomal aberrations were noticed at 2XLD50. The results concluded that CoCl2 induced DNA damage, cytokinesis failure and chromosomal aberrations in E. hortensis earthworms. PMID:26408983

  13. 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...

  14. 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

  15. Procedural Variation in Behavioral Avoidance Tests

    ERIC Educational Resources Information Center

    Bernstein, Douglas A.; Nietzel, Michael T.

    1973-01-01

    The data on approach to snakes provides srong support for the contention that the behavorial avoidance test is not immune to bias introduced by the operation of situational variables that have usually been allowed to vary in uncontrolled fashion in psychotherapy analogue research. Behavior of test subjects can be influenced not only in terms of…

  16. Earthworm cast production as a new behavioural biomarker for toxicity testing.

    PubMed

    Capowiez, Yvan; Dittbrenner, Nils; Rault, Magali; Triebskorn, Rita; Hedde, Mickaël; Mazzia, Christophe

    2010-02-01

    There is currently a lack of ecotoxicity tests adapted to earthworm species of higher ecological relevance and whose endpoints could be directly related to their ecological role in the soil. We propose a new and relatively simple ecotoxicity test based on the estimation of cast production (CP) by Lumbricus terrestris under laboratory conditions. CP was found to be linearly correlated to earthworm biomass and to be greatly influenced by soil water content. Azinphos-methyl had no effect on CP at all the concentrations tested. Significant decreases were observed at the normal application rate for other pesticides with (imidacloprid, carbaryl, methomyl) or without (ethyl-parathion and chlorpyrifos-ethyl) a clear concentration-effect response. For the highest concentration tested, reduction in CP varied between 35 and 67%. CP is straightforward and rapidly measured and ecologically meaningful. We thus believe it to be of great use as an endpoint in ecotoxicity testing. PMID:19783336

  17. 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.

  18. 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.

  19. 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

  20. Ecotoxicity of aged uranium in soil using plant, earthworm and microarthropod toxicity tests.

    PubMed

    Sheppard, S C; Stephenson, G L

    2012-01-01

    Discrepancies about probable no effect concentrations (PNEC) for uranium in soils may be because toxicity tests used freshly contaminated soils. This study used 3 soils amended with a range of uranium concentrations 10 years previously. The toxicity tests with northern wheatgrass (Elymus lanceolatus); earthworm (Eisenia andrei) were not affected below ~1,000 mg U kg(-1), and the soil arthropod Folsomia candida was not affected below ~350 mg U kg(-1). Survival of Orthonychiurus folsomi was diminished 20% (EC(20)) by ~85-130 mg U kg(-1), supporting a PNEC in the range of 100-250 mg U kg(-1) as derived previously. PMID:22033655

  1. 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.

  2. Recycled water sources influence the bioavailability of copper to earthworms.

    PubMed

    Kunhikrishnan, Anitha; Bolan, Nanthi S; Naidu, Ravi; Kim, Won-Il

    2013-10-15

    Re-use of wastewaters can overcome shortfalls in irrigation demand and mitigate environmental pollution. However, in an untreated or partially treated state, these water sources can introduce inorganic contaminants, including heavy metals, to soils that are irrigated. In this study, earthworms (Eisenia fetida) have been used to determine copper (Cu) bioavailability in two contrasting soils irrigated with farm dairy, piggery and winery effluents. Soils spiked with varying levels of Cu (0-1,000 mg/kg) were subsequently irrigated with recycled waters and Milli-Q (MQ) water and Cu bioavailability to earthworms determined by mortality and avoidance tests. Earthworms clearly avoided high Cu soils and the effect was more pronounced in the absence than presence of recycled water irrigation. At the highest Cu concentration (1,000 mg/kg), worm mortality was 100% when irrigated with MQ-water; however, when irrigated with recycled waters, mortality decreased by 30%. Accumulation of Cu in earthworms was significantly less in the presence of recycled water and was dependent on CaCl2-extractable free Cu(2+) concentration in the soil. Here, it is evident that organic carbon in recycled waters was effective in decreasing the toxic effects of Cu on earthworms, indicating that the metal-organic complexes decreased Cu bioavailability to earthworms. PMID:23122192

  3. 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

  4. 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

  5. Flight Tests Validate Collision-Avoidance System - Duration: 13 minutes.

    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 ...

  6. 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.

  7. 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

  8. 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.

  9. 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.

  10. Avoidance

    NASA Astrophysics Data System (ADS)

    Garcia, Ricardo; Caspari, Elizabeth; Ordemann, Anke; Moss, Frank

    2004-03-01

    The theory of Active Brownian Particles [1] is used to explain the motions of biological agents in central potentials, for example, the zooplankton Daphnia in light fields [2]. Two canonical motions are of interest: The first is a set of symmetric limit cycles in 2-D space wherein on average equal numbers of agents circle in opposite directions. The second motion occurs when the symmetry of the first is broken. Two symmetry breaking mechanisms have been suggested: velocity alignment and avoidance. Here we investigate the statistics of avoidance events between pairs of Daphnia. [1] U. Erdmann, W. Ebeling, L. Schimansky-Geier and F. Schweitzer, Brownian particles far from equilibrium. Eur. Phys. J. B 15, 105-113 (2000) [2] A. Ordemann, G. Balazsi and F. Moss, ``Pattern formation and stochastic motion of the zooplankton Daphnia in a light field'' Physica A, 325, 260-266 (2003).

  11. 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).

  12. Longitudinal in vivo MR imaging of live earthworms.

    PubMed

    Budán, Ferenc; Kovács, Noémi; Engelmann, Péter; Horváth, Ildikó; Veres, Dániel S; Németh, Péter; Szigeti, Krisztián; Máthé, Domokos

    2014-11-01

    Earthworm (Oligochaeta, Lumbricidae) species are used widely in eco-toxicological tests especially with contaminated soils. These long-term tests are reliable, but a high sample size is needed. Magnetic resonance imaging (MRI) can produce fast, robust, sensitive, and longitudinal morphological results using a small sample size. Performing longitudinal in vivo examinations of earthworms using MRI requires the need for anesthetics to completely avoid earthworm's moving. Our goal was to develop a simple and non-invasive method to anesthetize earthworms for in vivo longitudinal imaging studies. We investigated a number of different anesthesia methods and found that propan-2-ol and its vapor was optimal. We used a commercial sequential nanoScan® PET/MRI system (Mediso Ltd, Hungary, Budapest) to explore feasibility of MR imaging in immobilized earthworms. It was possible to visualize via micro MRI the brain, gastrointestinal tract, seminal vesicles, calciferous gland (Morren gland), and main blood vessels of the circulatory system. Our findings show the possibilities to examine changes in morphology using MRI of certain organs using a reversible, long-term immobilization method. PMID:25059556

  13. 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.

  14. 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 containing more plant species but little influenced by earthworms. Overall shoot biomass was decreased, root biomass increased in plant communities with more plant species. Earthworms decreased total shoot biomass in mesocosms with more plant species but did not affect biomass production of individual functional groups. Plant nitrogen concentrations across three focus species were 18% higher when earthworms were present; composition of plant communities did not affect plant quality. Conclusions Given the important role that both herbivores and earthworms play in structuring plant communities the implications of belowground-aboveground linkages should more broadly be considered when investigating global change effects on ecosystems. PMID:23668239

  15. 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...

  16. 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 responsible for changes in plant communities during the succession.

  17. 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

  18. 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

  19. 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…

  20. 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.

  1. Avoidance tests with small fish: determination of the median avoidance concentration and of the lowest-observed-effect gradient.

    PubMed

    Moreira-Santos, Matilde; Donato, Cristina; Lopes, Isabel; Ribeiro, Rui

    2008-07-01

    The purpose of the present study was to develop sensitive, rapid, and easily quantified avoidance tests for small fish (Danio rerio) in order to provide important ecological information during toxicity assessments. Fish were exposed in three replicate linear flow-through chambers consisting of five compartments. The test system was found to provide a linear contamination gradient, with mean dilutions in each compartment of 90, 70, 50, 30, and 10%. Also, in the absence of a toxic gradient, the fish were uniformly distributed along the five-compartment chambers. Then the apparatus was evaluated by exposing fish to a concentration gradient of copper and a dilution gradient of a field sample contaminated with acid mine drainage (AMD). Avoidance was monitored at 24-h intervals up to 96 h of exposure. The avoidance of copper and AMD by D. rerio was confirmed. The apparatus enabled quantification of median avoidance effect concentrations or dilutions (EC50 or EDil50) and also lowest-observed-effect gradients, which express the minimum toxicant gradient eliciting avoidance, a parameter increasing the ecological relevance of the laboratory avoidance responses. For quantifying avoidance, a 24-h exposure was sufficient, as the 24- to 96-h EC50 and EDil50 values were similar. The avoidance response was easy and rapid to quantify, leading this test to routine use in environmental risk assessment. PMID:18260687

  2. 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

  3. 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.

  4. 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

  5. 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 modules and avoid the duplication and one-off/custom developments of the past.

  6. 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

  7. COMPARATIVE TOXICITY OF CHEMICALS TO EARTHWORMS

    EPA Science Inventory

    The concentration-response (mortality) relationships of four species of earthworms, Eisentia fetida, Allolobophora tuberculata, Eudrilus eugeniae, and Perionyx excavatus are summarized for 62 chemicals and two test protocols. eibull function is used to summarize these data for ea...

  8. 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

  9. ACAT Ground Collision Avoidance Flight Tests Over - Duration: 2 minutes, 41 seconds.

    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...

  10. 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…

  11. 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…

  12. 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)

  13. 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.

  14. 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.

  15. A new test to avoid arterial complications during pancreaticoduodenectomy.

    PubMed

    Machado, Marcel Autran C; Herman, Paulo; Montagnini, André L; Costa, Marcelo L V; Nishinari, Kenji; Wolosker, Nelson; Machado, Marcel C C

    2004-01-01

    Celiac trunk or superior mesenteric artery stenosis are usually innocuous conditions. In such patients, arterial blood supply to the stomach, spleen, liver and bowel is sustained through extraordinarily well-developed pathways through the pancreas. If division of these collateral vessels is necessary during a surgical procedure such as pancreaticoduodenectomy, life-threatening celiac organ or bowel ischemia may occur. The authors describe a new test, using pancreatic inflow occlusion, to reliably identify celiac trunk or superior mesentery artery stenosis. The authors describe two cases of celiac axis occlusion and one case of superior mesenteric artery stenosis. In all three presented cases the gastroduodenal artery clamping test was negative and ischemia was only noticed after pancreatic section, suggesting that in severe occlusions this test may fail in diagnosing the vascular abnormality. All patients were successfully treated by revascularization with no operative mortality. If the diagnosis is unsuspected and in cases where appropriate angiographic studies have not been obtained before pancreatic resection, a test occlusion of the gastroduodenal artery should always precede its ligation. However, this test may not be effective in all cases and in instances where high suspicion of celiac axis or mesenteric stenosis is present, other maneuvers, such as pancreatic inflow test, could be helpful for the diagnosis of these rare and morbid situations. PMID:15532801

  16. The influence of time on lead toxicity and bioaccumulation determined by the OECD earthworm toxicity test.

    PubMed

    Davies, Nicola A; Hodson, Mark E; Black, Stuart

    2003-01-01

    Internationally agreed standard protocols for assessing chemical toxicity of contaminants in soil to worms assume that the test soil does not need to equilibrate with the chemical to be tested prior to the addition of the test organisms and that the chemical will exert any toxic effect upon the test organism within 28 days. Three experiments were carried out to investigate these assumptions. The first experiment was a standard toxicity test where lead nitrate was added to a soil in solution to give a range of concentrations. The mortality of the worms and the concentration of lead in the survivors were determined. The LC50s for 14 and 28 days were 5311 and 5395 microgPb g(-1)soil respectively. The second experiment was a timed lead accumulation study with worms cultivated in soil containing either 3000 or 5000 microgPb g(-1)soil. The concentration of lead in the worms was determined at various sampling times. Uptake at both concentrations was linear with time. Worms in the 5000 microg g(-1) soil accumulated lead at a faster rate (3.16 microg Pb g(-1)tissue day(-1)) than those in the 3000 microg g(-1) soil (2.21 microg Pb g(-1)tissue day(-1)). The third experiment was a timed experiment with worms cultivated in soil containing 7000 microgPb g(-1)soil. Soil and lead nitrate solution were mixed and stored at 20 degrees C. Worms were added at various times over a 35-day period. The time to death increased from 23 h, when worms were added directly after the lead was added to the soil, to 67 h when worms were added after the soil had equilibrated with the lead for 35 days. In artificially Pb-amended soils the worms accumulate Pb over the duration of their exposure to the Pb. Thus time limited toxicity tests may be terminated before worm body load has reached a toxic level. This could result in under-estimates of the toxicity of Pb to worms. As the equilibration time of artificially amended Pb-bearing soils increases the bioavailability of Pb decreases. Thus addition of worms shortly after addition of Pb to soils may result in the over-estimate of Pb toxicity to worms. The current OECD acute worm toxicity test fails to take these two phenomena into account thereby reducing the environmental relevance of the contaminant toxicities it is used to calculate. PMID:12475061

  17. 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…

  18. 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…

  19. 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...

  20. 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…

  1. 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…

  2. 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

  3. 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

  4. 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

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

    PubMed Central

    Shannon, Kyle M.; Gage, Gregory J.; Jankovic, Aleksandra; Wilson, W. Jeffrey

    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 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

  6. 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)

  7. Avoidance Behavior against Positive Allergens Detected with a Multiple Allergen Simultaneous Test Immunoblot Assay in Patients with Urticaria: Factors Associated with Avoidance Success/Failure

    PubMed Central

    Lee, Min Kyung; Kwon, In Ho; Kim, Han Su; Kim, Heung Yeol; Cho, Eun Byul; Park, Gyeong Hun; Park, Eun Joo; Kim, Kwang Ho; Kim, Kwang Joong

    2016-01-01

    Background Avoidance behavior against positive allergens detected by using multiple allergen simultaneous test (MAST)-immunoblot assay in patients with urticaria has been rarely reported. Objective We aimed to assess the avoidance behavior of patients with urticaria against positive allergens detected with a MAST. Methods One hundred and one urticaria patients who showed positivity to at least one allergen on a MAST completed a questionnaire regarding their test results. The avoidance behavior of the patients was evaluated, and relevant determining factors of avoidance success/failure were statistically assessed. Results We detected 144 different data (n=51, food allergens; n=17, pollen allergens; and n=76, aeroallergens) from 101 patients with urticaria. The avoidance failure rates were 33.3% for food allergens, 70.6% for pollen allergens, and 30.3% for aeroallergens. The pollen group showed a significantly higher avoidance failure rate than the food and aeroallergen groups (p<0.05). The patients with higher educational levels or more severe urticaria tended to successfully avoid allergens (p<0.05). The monthly household income level and patients' reliability to the test showed borderline correlations (p=0.057 and p=0.075, respectively). Conclusion We believe that the results of this study could be helpful in predicting avoidance success or failure against allergens in patients with urticaria when clinicians conduct allergen-specific immunoglobulin E tests. PMID:26848222

  8. 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. PMID:24122142

  9. 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

  10. 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.

  11. Test anxiety and the hierarchical model of approach and avoidance achievement motivation.

    PubMed

    Elliot, A J; McGregor, H A

    1999-04-01

    This research was designed to incorporate the test anxiety (TA) construct into the hierarchical model of approach and avoidance achievement motivation. Hypotheses regarding state and trait TA were tested in 2 studies, and the results provided strong support for the predictions. State TA (specifically, worry) was documented as a mediator of the negative relationship between performance-avoidance goals and exam performance. The positive relationship between performance-approach goals and exam performance was shown to be independent of TA processes. A series of analyses documented the conceptual and functional convergence of trait TA and fear of failure (FOF), and further validation of the proposed integration was obtained by testing trait TA/FOF and state TA together in the same model. Mastery goals were positively and performance-avoidance goals negatively related to long-term retention. PMID:10234849

  12. 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

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

    PubMed Central

    Bybin, Viktor Alexandrovich; Stom, Daevard Iosifovich

    2015-01-01

    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

  14. Toxicokinetics of metals in the earthworm Lumbricus rubellus exposed to natural polluted soils--relevance of laboratory tests to the field situation.

    PubMed

    Giska, Iwona; van Gestel, Cornelis A M; Skip, Borys; Laskowski, Ryszard

    2014-07-01

    The aim of this study was to estimate the bioavailability of essential (Zn, Cu) and non-essential metals (Cd, Pb) to the earthworm Lumbricus rubellus exposed to soils originating from a gradient of metal pollution in Southern Poland. Metal uptake and elimination kinetics were determined and related to soils properties. Experimental results were compared with tissue metal concentrations observed in earthworms from the studied transect. Cd and Pb were intensively accumulated by the earthworms, with very slow or no elimination. Their uptake rate constants, based on 0.01 M CaCl2-extractable concentrations in the soils, increased with soil pH. Internal concentrations of Cu and Zn were maintained by the earthworms at a stable level, suggesting efficient regulation of these metals by the animals. The estimated uptake and elimination kinetics parameters enabled fairly accurate prediction of metal concentrations reached within a life span of L. rubellus in nature. PMID:24747106

  15. 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

  16. 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.

  17. 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

  18. 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.

  19. 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 Automatic Dependent Surveillance Broadcast (ADS-B). A single intruder aircraft was used during all the flight testing, a NASA Gulfstream III (G-III). During the course of the testing, six geometrically different near-collision scenarios were evaluated. These six scenarios were each tested using various combinations of sensors and collision avoidance software. Of the 54 planned test points 49 were accomplished successfully. Proteus flew a total of 21.5 hours during the testing and the G-III flew 19.8 hours. The testing fully achieved all flight test objectives. The Flight IPT performed an analysis to determine the accuracy of the simulation model used to predict the location of the host aircraft downstream during an avoidance maneuver. The data collected by this flight program was delivered to the Access 5 Cooperative Collision Avoidance (CCA) Work Package Team who was responsible for reporting on their analysis of this flight data.

  20. Saberliner flight test for airborne wind shear forward looking detection and avoidance radar systems

    NASA Technical Reports Server (NTRS)

    Mathews, Bruce D.

    1991-01-01

    Westinghouse conducted a flight test with its Sabreliner AN/APG-68 instrumented radar to assess the urban discrete/ground moving vehicle clutter environment. Glideslope approaches were flown into Washington National, BWI, and Georgetown, Delaware, airports employing radar mode timing, waveform, and processing configurations plausible for microburst windshear avoidance. The perceptions, both general and specific, of the clutter environment furnish an empirical foundation for beginning low false alarm detection algorithm development.

  1. 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.

  2. Avoidance behaviour of Eisenia fetida to carbofuran, chlorpyrifos, mancozeb and metamidophos in natural soils from the highlands of Colombia.

    PubMed

    García-Santos, Glenda; Keller-Forrer, Karin

    2011-07-01

    Earthworm avoidance behaviour test is an important screening tool in soil eco-toxicology. This test has been developed and validated under North American and European conditions. However, little research has been performed on the avoidance test in the tropics. This work demonstrates the potential suitability of the avoidance behaviour test as screening method in the highlands of Colombia using Eisenia fetida as the bio-indicator species on contaminated soils with carbofuran and chlorpyrifos. Though for the two active ingredients 100% avoidance was not reached, a curve with six meaningful concentrations is provided. No significant avoidance behaviour trend was found for mancozeb and methamidophos. Tests were conducted in the field yielded similar results to the tests carried out in the laboratory for chlorpyrifos and mancozeb. However, for the case of carbofuran and methamidophos, differences of more than double in avoidance were obtained. Divergence might be explained by soil and temperature conditions. PMID:21489597

  3. 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.

  4. Behavioral avoidance test for childhood obsessive-compulsive disorder: a home-based observation.

    PubMed

    Barrett, Paula; Healy, Lara; March, John S

    2003-01-01

    Obsessive-compulsive disorder (OCD) is one of the most debilitating of the anxiety disorders. As our knowledge about this childhood condition continues to grow, there is a need for controlled treatment-outcome trials with precise assessments that are sensitive to treatment change, to guide the development of effective interventions. To evaluate the efficacy of a treatment protocol, it is necessary to have reliable and sensitive measures of OCD symptoms, including measures of obsessions, compulsions, and related levels of distress and avoidance. Whilst structured diagnostic interviews, semistructured clinical interviews, and self-report measures have been widely used in the assessment of childhood OCD, related levels of behavioral distress and avoidance have not been measured in treatment-outcome trials. This study investigated the sensitivity of a behavioral avoidance test (BAT), conducted in the home environment, in assessing treatment-outcome effects for children and adolescents with OCD following a 14-week cognitive-behavioral therapy (CBT) family intervention, in comparison to children in an 8-week "waitlist" control group. The results of the current study strongly support the sensitivity of a standardized BAT in assessing treatment-related changes in children and adolescents with OCD. Implications and future directions for research are discussed. PMID:12647571

  5. 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.

  6. 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.

  7. Effect of chiral differences of metolachlor and its (S)-isomer on their toxicity to earthworms.

    PubMed

    Xu, Dongmei; Wen, Yuezhong; Wang, Kaixiong

    2010-11-01

    The effects of (Rac)-metolachlor and (S)-metolachlor on the avoidance behavior, bodyweight change and in vivo enzyme activity of earthworms (Eisenia foetida) were determined and compared in this study. The effects of (Rac)-metolachlor on the enzyme activities of E. foetida and bodyweight were more significant than those of (S)-metolachlor at the same concentrations. In the short term (2 d, 7 d), (S)-metolachlor had faster effects on cellulase and catalase activities of E. foetida. However, in the relatively long term (14 d, 28 d), (Rac)-metolachlor had higher toxic effects on cellulase and catalase activities. The inter-group difference between (Rac)-metolachlor and (S)-metolachlor on E. foetida enzyme activities was the most significant for catalase, and the least significant for cellulase. The test of avoidance behavior shows that earthworms are more sensitive to the stimulation of (Rac)-metolachlor than to that of (S)-metolachlor. The results will help to develop an understanding of the biologically mediated environmental processes of these two herbicides. PMID:20723980

  8. 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.

  9. 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.

  10. Earthworm biomarker responses on exposure to commercial cypermethrin.

    PubMed

    Muangphra, Ptumporn; Sengsai, Supanyika; Gooneratne, Ravi

    2015-05-01

    Cypermethrin is a synthetic pyrethroid insecticide used worldwide in agriculture, home pest control, disease vector control, and food safety. It accumulates in soil. Therefore, traces of cypermethrin may frequently appear in vegetables grown in contaminated soil. There is a push now to develop biomarkers as early warning indicators of environmental pollution. In this study, DNA damage (tail DNA%, tail length, and olive tail moment), the micronucleus, neutral red retention (NRR) time, and pinocytic adherence ability of coelomocytes were investigated in Pheretima peguana earthworms exposed to cypermethrin in filter paper tests. The NRR time of earthworm coelomocytes decreased significantly at a concentration of 3.5 × 10(-3) µg · cm(-2) (1/100 LC50 ) after 48 h exposure, with a highly negative correlation with cypermethrin concentration. Pinocytic adherence ability of coelomocytes also declined significantly at a cypermethrin concentration of 3.5 × 10(-2) µg · cm(-2) (1/10 LC50 ). The DNA damage to earthworm coelomocytes (tail DNA%, tail length, and olive tail moment) increased considerably at the highest concentration (3.5 × 10(-1) µg · cm(-2) ) although the correlation between tail DNA% and cypermethrin concentration was low. Thus, physiological biomarkers were more sensitive than the genotoxic effects in earthworms exposed to commercial cypermethrin. Although a suite of earthworm biomarkers could be used to evaluate cypermethrin terrestrial pollution, the NRR test is easier to conduct and a more sensitive indicator. PMID:24376091

  11. Effects of earthworm activity on fertility and heavy metal bioavailability in sewage sludge.

    PubMed

    Liu, Xiaoli; Hu, Chengxiao; Zhang, Shuzhen

    2005-08-01

    The potential for using earthworms (Eisenia fetida) to improve fertility and reduce copper and cadmium availability in sewage sludge was tested by laboratory incubation experiments. Results comparing sewage sludge with and without earthworm treatment showed that earthworm activity decreased the contents of organic matter, total nitrogen, but increased the contents of available nitrogen and phosphorus and had no significant effect on the contents of total phosphorus, total potassium and available potassium. After incubation of the sewage sludge with earthworms for 60 days, the contents of Cu and Cd in the earthworms increased with the increase of additional Cu up to 250 mg kg(-1) and Cd up to 10 mg kg(-1). Bioconcentration factors (BCF) were higher than 1 only for Cd when the addition rate was lower than 5 mg kg(-1), which indicates that the earthworms can only accumulate Cd when the concentration of Cd is low in sewage sludge. Bioavailability of Cd and Cu was evaluated by applying sewage sludge with and without earthworm treatment to soil and then growing cabbage plants. The results showed that earthworm treatment increased the biomass of cabbage and decreased the bioaccumulation of Cd and Cu in the cabbage plants. PMID:15979143

  12. Aporrectodea caliginosa, a suitable earthworm species for field based genotoxicity assessment?

    PubMed

    Klobu?ar, Göran I V; Stambuk, Anamaria; Srut, Maja; Husnjak, Ivana; Merkaš, Martina; Traven, Luka; Cvetkovi?, Zelimira

    2011-04-01

    There is a growing interest for the application of biomakers to field-collected earthworms. Therefore we have evaluated the usability of native populations of endogeic, widely distributed earthworm Aporrectodea caliginosa in the assessment of soil genotoxicity using the Comet assay. Validation of the Comet assay on earthworm coelomocytes has been established using commercially available Eisenia fetida exposed to copper, cadmium, and pentachlorophenol, along with A. caliginosa exposed to copper in a filter paper contact test. Neutral red retention time (NRRT) assay was conducted on copper exposed and field-collected earthworms. Significant DNA and lysosomal damage was measured using Comet and NRRT assays in native populations of A. caliginosa sampled from the polluted soils in the urban area in comparison to the earthworms from the reference site. The results of this study confirm the employment of A. caliginosa as a suitable species for the in situ soil toxicity and genotoxicity field surveys. PMID:21292364

  13. 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

  14. 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

  15. Test of Antonovsky's postulate: high sense of coherence helps people avoid negative life events.

    PubMed

    Hochwälder, Jacek

    2015-04-01

    This study tested Antonovsky's postulate that a high sense of coherence (SOC) helps people avoid negative life events. It was assumed that negative life events that were uncontrollable would not show this effect, while those events that potentially could be controlled would show a significant relationship with SOC. 1,012 female nurses (M age=46.9 yr.; SD=8.9) participated in this longitudinal study and were divided into groups with low, moderate, and high SOC. Sixteen negative life events were categorized into uncontrollable and controllable events, with the controllable events divided into three sub-categories. Five one-way analyses of variance (ANOVAs) for independent measures followed up with post hoc tests were performed, with the number of experienced events in a given category by each participant (at Time 2) as the dependent variable and the three SOC groups (formed at Time 1) as the independent variable. The results indicated that the high SOC group reported fewer controllable negative life events, while there was no significant relationship between the SOC level and uncontrollable negative life events. The findings support the postulate in Antonovsky's model, with the distinction between controllable and uncontrollable negative life events. PMID:25799118

  16. 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.

  17. 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)

  18. 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

  19. Phi index: a new metric to test the flush early and avoid the rush hypothesis.

    PubMed

    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

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

    PubMed

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

    2015-04-15

    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

  1. 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

  2. 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

  3. 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.

  4. 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

  5. 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.

  6. Toxicity assessment of free form of heavy metals in aqueous media on earthworm Eudrillus eugeniae.

    PubMed

    Sharma, V; Chaudhari, P R; Satyanarayan, S

    2011-01-01

    Metals are found in free and also in combined forms. In order to get information on the effect of free forms of heavy metals on earthworms the aqueous extracts of metals were tested on earthworms both in individual form and also in combined form. Different concentrations, i.e. 1 ppm, 5 ppm, and 10 ppm, were selected arbitrarily and were used in the experiments. Metals like copper, cadmium, chromium, zinc and lead were used. Earthworms' Eudrillus eugeniae activity, i.e. their response to the toxicity of metals, was monitored continuously for 5 h. It can be concluded that free form/ionic form/dissolved form of heavy metals are more toxic for earthworms, concurrent with findings of workers who have drawn same inference during studies on aquatic organisms. Earthworms can serve as biomarkers for wastewater and sludge treatment studies as they have shown typical adverse body reactions and symptoms altogether different in reaction to each of the metals during aqueous medium studies. It can be inferred that, if earthworms are utilised for treating wastewater and sludges containing these five heavy metals, one can ascertain the presence of individual metal concentrations in the wastewaters and sludges by studying the typical body reactions of earthworms during the treatment. PMID:21977671

  7. 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

  8. 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 substances present in the soil. PMID:24886977

  9. 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

  10. 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

  11. 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.

  12. 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

  13. 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

  14. 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

  15. 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…

  16. 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…

  17. 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

  18. Avoidance of nonsteroidal anti-inflammatory drugs after negative provocation tests in urticaria/angioedema reactions: Real-world experience.

    PubMed

    Bommarito, Luisa; Zisa, Giuliana; Riccobono, Francesca; Villa, Elisa; D'Antonio, Cristian; Calamari, Ambra M; Poppa, Mariangela; Moschella, Adele; Di Pietrantonj, Carlo; Galimberti, Maurizio

    2014-01-01

    Drug provocation tests (DPTs) are the gold standard in diagnosing nonsteroidal anti-inflammatory drug (NSAID) hypersensitivity; however, only few data about follow-up of patients with negative DPTs are actually available. The aim of this study was to assess patients' behavior in taking NSAIDs again and to evaluate NSAID tolerability after negative allergological workup. This is a follow-up study involving patients evaluated for history of cutaneous reactions (urticaria and or angioedema) after NSAID intake and with negative DPTs with the suspected NSAID. Patients were asked during a phone interview about the intake of NSAIDs, tolerance, or reasons of avoidance. The negative predictive value (NPV) of NSAIDs DPTs was calculated. One hundred eleven of 142 patients were successfully contacted; 46/111 (41.44%) took the same NSAID previously tested with two adverse reactions reported (4.34%). Fifty-three of 111 (47.74%) patients did not take the same NSAID, but 34 of them took at least another strong cyclooxygenase (COX) 1 inhibitor, with 1 adverse reaction (2.94%) and 19 of them took only weak COX-1 inhibitors. Twelve of 111 patients (10.8%) did not take any NSAID. Reasons for drug avoidance were mainly fear of reactions (70.8%) and no need (29.2%). NPV, overall, was 96.97% (95% confidence interval, 91-99%). Although NSAID hypersensitivity diagnosis was ruled out by oral provocation test, the majority of patients with a history of urticaria/angioedema avoided the intake of the tested NSAIDs for fear of new reactions, particularly when strong COX-1 inhibitor NSAIDs were involved. The high NPV value of DPT resulting from this study should reassure NSAID intake. PMID:24992549

  19. 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...

  20. 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

  1. Avoiding Split Attention in Computer-Based Testing: Is Neglecting Additional Information Facilitative?

    ERIC Educational Resources Information Center

    Jarodzka, Halszka; Janssen, Noortje; Kirschner, Paul A.; Erkens, Gijsbert

    2015-01-01

    This study investigated whether design guidelines for computer-based learning can be applied to computer-based testing (CBT). Twenty-two students completed a CBT exam with half of the questions presented in a split-screen format that was analogous to the original paper-and-pencil version and half in an integrated format. Results show that students…

  2. Using artificial intelligence for automating testing of a resident space object collision avoidance system on an orbital spacecraft

    NASA Astrophysics Data System (ADS)

    Straub, Jeremy

    2014-06-01

    Resident space objects (RSOs) pose a significant threat to orbital assets. Due to high relative velocities, even a small RSO can cause significant damage to an object that it strikes. Worse, in many cases a collision may create numerous additional RSOs, if the impacted object shatters apart. These new RSOs will have heterogeneous mass, size and orbital characteristics. Collision avoidance systems (CASs) are used to maneuver spacecraft out of the path of RSOs to prevent these impacts. A RSO CAS must be validated to ensure that it is able to perform effectively given a virtually unlimited number of strike scenarios. This paper presents work on the creation of a testing environment and AI testing routine that can be utilized to perform verification and validation activities for cyber-physical systems. It reviews prior work on automated and autonomous testing. Comparative performance (relative to the performance of a human tester) is discussed.

  3. 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 Morpheus vehicle.

  4. 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 Morpheus vehicle.

  5. 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 200mg·kg(-1) was significantly toxic to both the survival and the growth of earthworms. DDT significantly stimulated GST and CAT activity in earthworms after 14days. The CAT and GST activities were also stimulated by DDT exposure at rates of 100mg·kg(-1) after chronic exposure (42days). The results provide implications for validating the extrapolation from laboratory simulated soils criteria to contaminated soils and for making site risk assessments. PMID:26969436

  6. 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

  7. 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...

  8. 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

  9. 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 food web influence on nutrient cycling. PMID:21935465

  10. 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

  11. 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 less abundant in the earthworm removal plots. There was a significant positive earthworm effect on the rate and thermal sensitivity of soil respiration. Soil respiration was consistently higher in plots with tulip poplar litter than those with beech litter, indicating a strong influence of plant residue quality. However, the differences were smaller in the second year than in the first one indicating an adaptation of the soil system. Oak and beech seedlings were smaller in high density earthworm plots, while the reverse was true for maple and tulip poplar seedlings. Non-native earthworms affect below- and aboveground processes, however, these effects depend on forest type and land use history. The earthworm effects also appear to be dynamic, as witnessed by a recent invasion of an Asian earthworm species in one of our forest stands.

  12. 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.

  13. 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

  14. 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.

  15. 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

  16. A SMA Actuated Earthworm-Like Robot

    NASA Astrophysics Data System (ADS)

    Wang, Y. K.; Song, C. N.; Wang, Z. L.; Guo, C.; Tan, Q. Y.

    Inspired by locomotion principle of earworms, a shape memory alloy (SMA) actuated earthworm-like robot is designed and developed in this paper. Four groups of SMA wires as actuator and one spring as accumulator were introduced. The SMA wires and spring play a role in contraction and extension of an earthworm muscle respectively. For temporal position stopping control, two groups of electromagnets were used as setae of earthworm. By SMA wires were driven independently or simultaneity according to defined movement patterns, the all-round movement of the artificial earthworm freely to different directions was realized. A series of experiments on the self-developed robot moving and turning with different actuation frequencies were carried out. The results showed the validity of the locomotion mobility of the SMA actuated earworm-like robot.

  17. 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, B.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.

  18. Comparison of earthworm responses to petroleum hydrocarbon exposure in aged field contaminated soil using traditional ecotoxicity endpoints and 1H NMR-based metabolomics.

    PubMed

    Whitfield Åslund, Melissa; Stephenson, Gladys L; Simpson, André J; Simpson, Myrna J

    2013-11-01

    (1)H NMR metabolomics and conventional ecotoxicity endpoints were used to examine the response of earthworms exposed to petroleum hydrocarbons (PHCs) in soil samples collected from a site that was contaminated with crude oil from a pipeline failure in the mid-1990s. The conventional ecotoxicity tests showed that the soils were not acutely toxic to earthworms (average survival ? 90%), but some soil samples impaired reproduction endpoints by >50% compared to the field control soil. Additionally, metabolomics revealed significant relationships between earthworm metabolic profiles (collected after 2 or 14 days of exposure) and soil properties including soil PHC concentration. Further comparisons by partial least squares regression revealed a significant relationship between the earthworm metabolomic data (collected after only 2 or 14 days) and the reproduction endpoints (measured after 63 days). Therefore, metabolomic responses measured after short exposure periods may be predictive of chronic, ecologically relevant toxicity endpoints for earthworms exposed to soil contaminants. PMID:23938450

  19. Can avoidance behavior of the mite Oppia nitens be used as a rapid toxicity test for soils contaminated with metals or organic chemicals?

    PubMed

    Owojori, Olugbenga J; Healey, Janell; Princz, Juliska; Siciliano, Steven D

    2011-11-01

    Survival and reproduction soil toxicity tests for a new mite test species, Oppia nitens, have recently been developed for boreal ecosystems; however, the tests require 28 to 35 d. Avoidance tests have the potential to allow for rapid preliminary screening assessments of soils. The objective of this investigation was to determine the relevance of the avoidance test with the oribatid mite O. nitens as a short screening test in lower-tier environmental risk assessment. We assessed the effects of soil properties and chemicals on O. nitens avoidance behavior as well as the minimum time required to obtain a significant avoidance response from the mite. Specimens of this mite were exposed in Organisation for Economic Co-Operation and Development (OECD) artificial soils that had been adjusted to achieve varying soil properties as well as to a range of concentrations of the following contaminants: Cu, Zn, Cd, Pb, phenanthrene, benzo[a]pyrene, geraniol, and boric acid over 1, 2, or 5 d. The results were then compared with those of parallel life-cycle toxicity studies. The results showed that 24 h was adequate to obtain a significant response of the mites and that the soil properties tested (moisture, pH, organic matter, and clay content) had little influence on mite avoidance. The median effective concentration (EC50) for avoidance response was lower than or in the same range as the reproduction EC50 values for the organic compounds (phenanthrene and geraniol) and metals (Cu and Zn) or the median lethal concentration (LC50) values for Pb. The 24-h mite avoidance test is a suitable screening method across a range of soil properties and chemicals. PMID:21898558

  20. Assessment of hydraulic conductivity distribution from ERT-monitored tracer tests avoiding the need for petrophysical relationships

    NASA Astrophysics Data System (ADS)

    Crestani, E.; Camporese, M.; Salandin, P.

    2013-12-01

    Geophysical methods, such as the Electrical Resistivity Tomography (ERT), have been increasingly used in recent years to analyze the erratic behavior of plumes in natural aquifers. In particular, borehole ERT monitoring of saline tracer tests allows to collect 2D time-lapse electrical data in a control plane, related to spatio-temporal variations of salt concentration within the aquifer. The electrical conductivity (EC) field is reconstructed by means of a geophysical inversion on the basis of raw resistance data, while a petrophysical relationship (e.g., Archie's law) is usually needed to map EC data into solute concentrations, thus retrieving the plume evolution. The latter, in turn, is often used to evaluate the hydraulic conductivity (K) distribution by inverse modeling. To avoid the need for an in-situ specific calibration of a petrophysical relationship and the previous knowledge of the concentration spatio-temporal evolution, this study proposes a new approach for retrieving the K distribution from an ERT monitored saline tracer test, based on travel time modeling of transport integrated with the ensemble Kalman filter (EnKF). The definition of the solute transport in terms of travel times allows to analyze the sequence of changes in electrical conductivity deduced from an ERT survey without converting the electrical data into concentrations. To do this, a specific travel time procedure is applied: the control plane is subdivided in properly spaced sub-control planes and the cumulative distribution function of the travel time in each of them is independently calculated and then assimilated through EnKF, which allows to update the K distribution. Our approach, initially tested in 3D synthetic aquifers, is here applied to the experimental site of Settolo, Valdobbiadene (TV), where a tracer test monitored by ERT has been carried out. The results show that the suggested method seems to be effective in reproducing the erratic distribution of the hydraulic conductivity at the local scale, which control the non-Fickian evolution of plumes in natural aquifers.

  1. [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

  2. The implications of copper fungicide usage in vineyards for earthworm activity and resulting sustainable soil quality.

    PubMed

    Eijsackers, H; Beneke, P; Maboeta, M; Louw, J P E; Reinecke, A J

    2005-09-01

    To investigate the impact of copper-containing fungicides (copper oxychloride) on earthworms in South African vineyards, field inventories of earthworms in and between vine rows were carried out and compared to directly adjacent grassland. Also copper content, pH, organic matter content, and soil porosity were determined in these soils. This was combined with laboratory experiments to study the impact of vineyard soil characteristics on the burrowing and dispersal behavior of earthworms. Moreover, the direct toxic action of copper oxychloride on different endpoints of the earthworms (survival and growth) was studied. Copper oxychloride had a negative impact on these endpoints (decreased growth and survival related to increased copper body content) as well as on the behavioral aspect (decreased burrowing rate and avoidance of copper-containing soil). Moreover, there was an inverse relation between burrowing activity and soil bulk density that could also be related to the copper content. This may lead to a decrease in sustainable soil quality in vineyards. PMID:15978295

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

    USGS Publications Warehouse

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

    2015-01-01

    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.

  4. 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

  5. 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 airtight chamber. Stable isotope mass balance calculation is used to estimate the recovery of litter-derived carbon from three pools (earthworm tissue, SOM, remaining litter), the loss of litter-derived carbon through soil respiration, and the contribution of different carbon sources to soil CO2 efflux in different earthworm treatments. Our results show that earthworm species recognized as 'soil feeders' have 13C and 15N values that are 1.2‰ and 3.8‰ higher than those of 'litter feeders', and 15N also differ significantly amount different soil feeders, suggesting different food resource usage even within the same functional group. There are strong species effects on both leaf litter disappearance rate and CO2 efflux rate, both being high when Amynthas earthworms are present. Our results suggest that changing earthworm species composition leads to changing resource use, which alters the fate of organic carbon in the forest floor and soil and could potentially affect long-term SOM dynamics in temperate forests.

  6. The relative toxicities of insecticides to earthworms of the Pheretima group (Oligochaeta).

    PubMed

    Mostert, Magdel A; Schoeman, At S; van der Merwe, Mac

    2002-05-01

    An artificial soil test was used to determine the LC50 values of carbaryl, chlorpyrifos, imidacloprid, cyfluthrin and fipronil against earthworms of the Pheretima group. For a 24-h interval, carbaryl was the most toxic to earthworms (LC50 = 77 mg kg-1), followed by imidacloprid (155 mg kg-1), cyfluthrin (351 mg kg-1), chlorpyrifos (390 mg kg-1) and fipronil (> 8550 mg kg-1) as the least toxic. For the 48-h and 7-day intervals, imidacloprid was the most toxic to earthworms (LC50 = 5 mg kg-1 and 3 mg kg-1 respectively), followed by carbaryl (16 mg kg-1; 9 mg kg-1), cyfluthrin (128 mg kg-1; 110 mg kg-1), chlorpyrifos (330 mg kg-1; 180 mg kg-1) and the least toxic was fipronil (> 8550 mg kg-1 both intervals). The surface application rates required to achieve these values are compared with the rates recommended for the control of turfgrass pests. PMID:11997970

  7. 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

  8. Feasibility of vermistabilization for fresh pelletized dewatered sludge with earthworms Bimastus parvus.

    PubMed

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

    2014-11-01

    The aim of this study was to investigate the feasibility of vermistabilization of fresh pelletized dewatered sludges (PDS) without any bulking materials using earthworms Bimastus parvus. For this, two pelletized treatments with 4.5mm and 14.5mm fresh PDS and one without pelletized treatment were setup. Earthworm's fate test showed that earthworms could not survive in the treatment without pelletisation. For two pelletized treatments, B. parvus had a good life, producing great numbers of cocoons and hatchlings, after 60days. Vermicomposting of PDS resulted in the decreases of DOC, ammonia-nitrogen and microbial biomass and activity while increases of electrical conductivity and nitrate-nitrogen and available phosphorous. These findings suggest the stable and beneficial vermicomposts were achieved. The overall results evidenced that the fresh PDS without blending could be directly stabilized by vermicomposting and the vermireactor containing 4.5mm PDS displayed a better performance than 14.5mm PDS. PMID:25465793

  9. 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.

  10. Earthworm muscle preparation for studying several potent compounds--the possible existence of a "Soman receptor.".

    PubMed

    Chou, T C; Zhou, J Q

    1981-01-01

    A new model of earthworm (Eisenia foedida) dorsal muscle preparation was studied. It is a specific preparation for testing GABA and its agonist muscimol. The response of muscle could be recorded through mechanical functional changes instead of potential variations. Thus, it is a direct and simple means for measuring GABA activity. ChE-deactivated preparation was suggested for this purpose. By mild membrane modifications of earthworm muscle preparation, it was possible to remove or inactivate GABA, glutamic acid or Soman combining protein. In conjunction with superfusion of Ach-receptor antagonist (alpha-Bungaratoxin) or GABA antagonist (picrotoxin, isopropylbicyclophosphate), we could differentiate Soman receptor from Ach and GABA receptor. The possible existence of a Soman receptor in the earthworm muscle was therefore proposed. PMID:6307797

  11. 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)

  12. 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 accompanied by a change in the microbial community diversity and/or function. PMID:22363763

  13. 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.

  14. 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 10mgkg(-1) soil experienced transient oxidative stress and exhibited reduced burrowing activity and respiration after an 8-week exposure; EF at 0.1 and 1.0mgkg(-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

  15. Geographic variation of freeze-tolerance in the earthworm Dendrobaena octaedra.

    PubMed

    Rasmussen, L M; Holmstrup, M

    2002-12-01

    Freeze-tolerance and some of the underlying biochemical defence mechanisms in the earthworm Dendrobaena octaedra was investigated. Survival after slow cooling to -2 degrees C, -4 degrees C, or -6 degrees C was analysed in D. octaedra from three geographic regions representing large differences in winter temperature (Denmark, Finland and Greenland). A large variation in freeze-tolerance between the three populations of D. octaedra was found. Earthworms from the northern populations (Finland and Greenland) tolerated lower temperatures (-6 degrees C) than earthworms from the Danish population (poor survival at -4 degrees C and -2 degrees C). In the Finnish population, freezing led to the production of high concentrations of glucose, which reached values much higher than controls (94 mg g(-1) vs. 2 mg g(-1) dry weight). Other potential cryoprotectants were not elevated after freezing. The Danish and Greenlandic populations had substantially lower mean glucose levels after freezing than the Finnish population (about 15 mg g(-1)). Danish earthworms rapidly frozen did not accumulate glucose, and did not survive freezing at -2 degrees C. Danish earthworms exposed to osmotic stress in Ringer's solutions, containing different concentrations of glycerol, showed significantly elevated glucose levels, but did not survive rapid freezing. It was determined if freezing had an influence on the reproduction of the earthworms. After warming to summer temperatures (15 degrees C), survivors of freezing produced viable cocoons. In a field experiment it was tested if natural acclimatization during autumn and winter months had an effect on freeze-tolerance in the Danish population. There was a significant increase of post-freeze survival during this period. The results of the freezing experiments are discussed in relation to the general ecology of D. octaedra. PMID:12444468

  16. Influence of soil properties on bioaccumulation of 14C-simazine in earthworms Eisenia foetida.

    PubMed

    de Andréa, Mara M; Papini, Solange

    2005-01-01

    The toxicity of pesticides has been evaluated by several methods including tests with earthworms in both artificial and natural soils treated with the compounds. The ecological niches of earthworms make them good bioindicators of soil contamination. The bioaccumulation of 14C-simazine (6-chloro-N2-N4-diethyl- 1,3,5-triazine-2,4-diamine) was evaluated in earthworms (Eisenia foetida) maintained during three months in two substrates with different physical-chemical characteristics. The substrates were treated with 3.0 mg and 330 kBq of 14C-simazine kg(-1) substrate. Results indicated that worms did not influence simazine dissipation in both substrates as indicated by similar recoveries and with no statistical differences with and without earthworms. The radiocarbon recoveries were 86.8 and 95.3%, respectively in the substrates with lower and higher organic matter contents with earthworms, and 91.0 and 107.4% in the same substrates without worms. However, in earthworms the recoveries were statistically higher when they were maintained in the substrate with lower amount of organic matter (0.89%) than from the higher one (0.33%). Consequently, 14C-simazine bioconcentration factor (BCF) was also greater in the substrate with lower organic matter (6.89+/-1.55) than in the substrate with higher organic matter content (0.88+/-0.06). The results suggest that the higher soil organic matter content will cause lower probability of contamination of soil organisms with simazine. PMID:15656162

  17. Metal remediation from partially composted distillery sludge using composting earthworm Eisenia fetida.

    PubMed

    Suthar, Surindra

    2008-09-01

    Distillery sludge, a sugar industry byproduct, has been recommended widely as a potential soil conditioner, but high concentrations of metals limit its continuous use for field crops. In this study we tested the feasibility of earthworm Eisenia fetida (Savigny) in removing metals (Fe, Cu, Zn, Pb) from sludge through vermitechnology. The transfer of metals during the vermicomposting process was also estimate in terms of total metal contents in vermicomposted sludge and earthworm tissues. The sludge processed by worms showed a significant reduction in concentration of metals: Zn (20.5-43.8%), Fe (23.6-34.0%), Mn (18.0-45.7%) and Cu (29.0-58.1%), at the end. The metal reduction in sludge was directly related to the bioaccumulation of metals in the tissues of composting earthworms. The inoculated earthworms showed a considerable level (dry wt basis) of Zn (103.7-143.3 mg kg(-1)), Fe (87.2-146.5 mg kg(-1)), Mn (83.7-138.6 mg kg(-1)) and Cu (16.8-25.5 mg kg(-1)) in their tissues. A higher range of bioconcentration factors (BCFs) for different metals studied further suggest the candidature of earthworm to be used effectively for removal of metals form industrial sludges. The obtained vermicomposts form different vermireactors were rich in nutrients. The feasibility of earthworms to mitigate the metal toxicity and to enhance the nutrient profile in sludge might be useful in sustainable land restoration practices at low-input basis. The ranges of metals in end product were within the standards recommended by different agencies. PMID:18728904

  18. Shade Avoidance

    PubMed Central

    Casal, Jorge J.

    2012-01-01

    The presence of neighboring vegetation modifies the light environment experienced by plants, generating signals that are perceived by phytochromes and cryptochromes. These signals cause large changes in plant body form and function, including enhanced growth of the hypocotyl and petioles, a more erect position of the leaves and early flowering in Arabidopsis thaliana. Collectively, these so-called shade-avoidance responses tend to reduce the degree of current or future shade by neighbors. Shade light signals increase the abundance of PHYTOCHROME INTERACTING FACTOR 4 (PIF4) and PIF5 proteins, promote the synthesis and redirection of auxin, favor the degradation of DELLA proteins and increase the expression of auxin, gibberellins and brassinosteroid-promoted genes, among other events downstream the photoreceptors. Selectively disrupting these events by genetic or pharmacological approaches affects shade-avoidance responses with an intensity that depends on the developmental context and the environment. Shade-avoidance responses provide a model to investigate the signaling networks used by plants to take advantage of the cues provided by the environment to adjust to the challenges imposed by the environment itself. PMID:22582029

  19. 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.

  20. The environmental safety of eprinomectin to earthworms.

    PubMed

    Halley, Bruce A; Winter, Renate; Yoon, Stephen; Marley, S E; Rehbein, Steffen

    2005-03-10

    A study was conducted to assess the environmental safety of the endectocide eprinomectin to the earthworm Lumbricus terrestris under conditions mimicking typical product use on pasture. The LC50 value of eprinomectin in artificial soil after 28 days of exposure is higher than the levels expected in feces from dosed cattle or in soil fertilized with manure from dosed cattle, which indicates a wide margin of safety for this compound to earthworms. However, the no-observed-effect concentration has not been established. Therefore, the current study was conducted to determine whether there would be any effects on earthworms from feces from cattle treated with the commercial formulation of eprinomectin. Feces were collected rectally from grazing cattle on Day 0 before treatment and on Days 2, 4, 7 and 14 after treatment with EPRINEX (eprinomectin) Pour-On for Beef and Dairy Cattle (Merial Limited) at 0.5 mg eprinomectin per kg bodyweight. Assays of eprinomectin B1a (the major component of eprinomectin) were 0, 0.427, 0.152, 0.0512 and 0.00185 mg kg-1 wet weight of feces (equivalent to 0, 3.34, 1.19, 0.40 and 0.010 mg kg-1 on a dry weight basis, respectively). No significant differences (p>0.05) were observed at any day post-treatment in the survival or behavioral effects of any worms fed post-dose feces relative to the worms fed control feces. All post-dose comparisons of weight changes of living earthworms to the control group were not significantly different (p>0.05), indicating that treatment of cattle with EPRINEX (eprinomectin) Pour-On for Beef and Dairy Cattle did not affect feeding or weight gain of the earthworms. The LC50 value and the results of this study establish the wide margin of safety afforded to earthworms by eprinomectin under typical usage conditions. PMID:15725539

  1. 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.

  2. 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

  3. 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

  4. 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.

  5. 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.

  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. 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...

  8. 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.

  9. Zwitterionic digalactosylceramides from the earthworm, Pheretima asiatica.

    PubMed

    Tanaka, R; Miyahara, K; Noda, N

    1996-06-01

    Nine homogeneous glycosphingolipids were isolated from the earthworm, Pheretima asiatica (Annelida). All of them are digalactosylceramides carrying a choline phosphate group in the outer galactose moiety. Their full structures including the position of a phosphocholine unit were determined based on chemical and spectral evidence. PMID:8814945

  10. 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…

  11. 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 (?-glucosidase, cellobiohydrolase, chitinase, xylanase, leucine-aminopeptidase, and phosphatase. Zymography showed higher activity of ?-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.

  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. Earthworm symbiont Verminephrobacter eiseniae mediates natural transformation within host egg capsules using type IV pili

    PubMed Central

    Davidson, Seana K.; Dulla, Glenn F.; Go, Ruth A.; Stahl, David A.; Pinel, Nicolás

    2014-01-01

    The dense microbial communities commonly associated with plants and animals should offer many opportunities for horizontal gene transfer through described mechanisms of DNA exchange including natural transformation (NT). However, studies of the significance of NT have focused primarily on pathogens. The study presented here demonstrates highly efficient DNA exchange by NT in a common symbiont of earthworms. The obligate bacterial symbiont Verminephrobacter eiseniae is a member of a microbial consortium of the earthworm Eisenia fetida that is transmitted into the egg capsules to colonize the embryonic worms. In the study presented here, by testing for transformants under different conditions in culture, we demonstrate that V. eiseniae can incorporate free DNA from the environment, that competency is regulated by environmental factors, and that it is sequence specific. Mutations in the type IV pili of V. eiseniae resulted in loss of DNA uptake, implicating the type IV pilus (TFP) apparatus in DNA uptake. Furthermore, injection of DNA carrying antibiotic-resistance genes into egg capsules resulted in transformants within the capsule, demonstrating the relevance of DNA uptake within the earthworm system. The ability to take up species-specific DNA from the environment may explain the maintenance of the relatively large, intact genome of this long-associated obligate symbiont, and provides a mechanism for acquisition of foreign genes within the earthworm system. PMID:25400622

  14. 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-?-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

  15. Earthworm symbiont Verminephrobacter eiseniae mediates natural transformation within host egg capsules using type IV pili.

    PubMed

    Davidson, Seana K; Dulla, Glenn F; Go, Ruth A; Stahl, David A; Pinel, Nicolás

    2014-01-01

    The dense microbial communities commonly associated with plants and animals should offer many opportunities for horizontal gene transfer through described mechanisms of DNA exchange including natural transformation (NT). However, studies of the significance of NT have focused primarily on pathogens. The study presented here demonstrates highly efficient DNA exchange by NT in a common symbiont of earthworms. The obligate bacterial symbiont Verminephrobacter eiseniae is a member of a microbial consortium of the earthworm Eisenia fetida that is transmitted into the egg capsules to colonize the embryonic worms. In the study presented here, by testing for transformants under different conditions in culture, we demonstrate that V. eiseniae can incorporate free DNA from the environment, that competency is regulated by environmental factors, and that it is sequence specific. Mutations in the type IV pili of V. eiseniae resulted in loss of DNA uptake, implicating the type IV pilus (TFP) apparatus in DNA uptake. Furthermore, injection of DNA carrying antibiotic-resistance genes into egg capsules resulted in transformants within the capsule, demonstrating the relevance of DNA uptake within the earthworm system. The ability to take up species-specific DNA from the environment may explain the maintenance of the relatively large, intact genome of this long-associated obligate symbiont, and provides a mechanism for acquisition of foreign genes within the earthworm system. PMID:25400622

  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. LBP/BPI homologue in Eisenia andrei earthworms.

    PubMed

    Škanta, František; Procházková, Petra; Roubalová, Radka; Dvo?ák, Ji?í; 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

  18. [Ecotoxicological effects of chlorotetracycline on earthworm in soil].

    PubMed

    Ji, Zhan-Hua; An, Jing; Xiao, Ming-Yue; Wei, Shu-He; Tai, Pei-Dong; Lu, Ze

    2014-10-01

    Eiseniafoetida was selected to investigate the ecotoxicological effects of chlorotetracycline on the earthworm in soil. The results showed that 1, 10 and 100 mg · kg(-1) chlorotetracycline had no significant effects on earthworm's body mass after a 7-d exposure, but it was significantly inhibited by 10, 100 mg · kg(-1) chlorotetracycline after 21 days. The soluble protein content of earthworm was induced by 1, 10 and 100 mg · kg(-1) chlorotetracycline, and showed a positive response as the con- centration increased. Also, the earthworm treated by 1, 10 and 100 mg · kg(-1) chlorotetracycline induced the increases of SOD, POD and CAT activities to different degrees. The gene expression in earthworm changed significantly after a 28-d exposure. It is suggested that chlorotetracycline had a chronic ecotoxicological effect on earthworm, and the body mass, soluble protein, antioxidant en- zyme and gene expression could be used as the biomarkers to estimate chlorotetracycline toxicity. PMID:25796913

  19. 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

  20. 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.

  1. 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

  2. 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

  3. Earthworm mucus stimulates oviposition in a predatory fly (Diptera: Anthomyiidae).

    PubMed

    Morris, D E; Pivnick, K A

    1991-11-01

    Coenosia tigrina larvae feed on earthworms. We hypothesized that earthworm mucus contains a kairomone that stimulates oviposition behavior in adultC. tigrina females, thus minimizing the search area in the soil required for newly eclosed larvae to find earthworms. In bioassays, adult females responded with extension of the ovipositor 25-43% of the time to earthworm-mucus-soaked filter paper disks compared to 6-7% in response to water-soaked disks. Ovipositor extension on mucus-soaked disks was followed by egg-laying 29% of the time and 0% of the time on water-soaked disks. Egg-laying byC. tigrina followed a diurnal periodicity, with most eggs laid in the latter half of the photophase even in the absence of earthworm mucus. More eggs were deposited from 1600 to 1800 hr by females given access to earthworm mucus during that period than were deposited by females not given access. There was no difference in the number of eggs deposited from 0600 to 0800 hr, by females given access to earthworm mucus or not. This is a time of day when few eggs are normally laid. This paper is the first report of an earthworm-produced kairomone in an insect-earthworm interaction. The kairomone may have potential for enhancing biological control of the onion maggot,Delia antiqua, which is a prey of adultC. tigrina. PMID:24258588

  4. Effects of earthworm cast and powdered activated carbon on methane removal capacity of landfill cover soils.

    PubMed

    Park, Soyoung; Lee, Incheol; Cho, Changhwan; Sung, Kijune

    2008-01-01

    Landfill gases could be vented through a layer of landfill cover soil that could serve as a biofilter to oxidize methane to carbon dioxide and water. Properly managed landfill cover soil layers may reduce atmospheric CH4 emissions from landfills. In the present study, the effects of earthworm cast and powdered activated carbon (PAC) on the CH4 removal capacity of the landfill cover soil was investigated. For this purpose, column and batch tests were conducted using three different materials: typical landfill cover soil, landfill cover soil amended with earthworm cast, and landfill cover soil amended with PAC. The maximum CH4 removal rate of the columns filled with landfill cover soil amended with earthworm cast was 14.6mol m(-2)d(-1), whereas that of the columns filled with typical landfill cover soil was 7.4mol m(-2)d(-1). This result shows that amendment with earthworm cast could stimulate the CH4-oxidizing capacity of landfill cover soil. The CH4 removal rate of the columns filled with landfill cover soil amended with PAC also showed the same removal rate, but the vertical profile of gas concentrations in the columns and the methanotrophic population measured in the microbial assay suggested that the decrease of CH4 concentration in the columns is mainly due to sorption. Based on the results from this study, amendment of landfill cover soil with earthworm cast and PAC could improve its CH4 removal capacity and thus achieve a major reduction in atmospheric CH4 emission as compared with the same landfill cover soil without any amendment. PMID:17764722

  5. 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

  6. 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

  7. 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

  8. Glycerophosphocholines of the earthworm, Pheretima asiatica.

    PubMed

    Tanaka, R; Noda, N; Miyahara, K

    1999-08-01

    The lipid composition of the earthworm, Pheretima asiatica (Annelida), was analyzed. Four glycerophospholipids, together with four known glycosphingolipids, were isolated in pure form. The former four were 1-alkyl 2-acyl glycerophosphocholines possessing a C17:0 and/or C18:1 fatty acid residue. Their structures, including the position and geometry of the double bond, were determined on the bases of chemical and spectral data. PMID:10478472

  9. 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.

  10. 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.

  11. 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

  12. Biochemical diversity of betaines in earthworms.

    PubMed

    Liebeke, Manuel; Bundy, Jacob G

    2013-01-25

    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 (1)H-(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 (1)H and (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. PMID:23261439

  13. 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

  14. 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.

  15. Collision Avoidance System

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Ames Research Center teamed with the Federal Aviation Administration (FAA) to study human performance factors associated with the use of the Traffic Alert and Collision Avoidance system (TCAS II) in an operational environment. TCAS is designed to alert pilots of the presence of other aircraft in their vicinity, to identify and track those who could be a threat, and to recommend action to avoid a collision. Ames conducted three laboratory experiments. The first showed that pilots were able to use the TCAS II correctly in the allowable time. The second tested pilots' response to changes in the avoidance advisories, and the third examined pilots' reactions to alternative displays. After a 1989 congressional mandate, the FAA ruled that TCAS would be required on all passenger carrying aircraft (to be phased in completely by 1995).

  16. Stimulus conflict triggers behavioral avoidance.

    PubMed

    Dignath, David; Eder, Andreas B

    2015-12-01

    According to a recent extension of the conflict-monitoring theory, conflict between two competing response tendencies is registered as an aversive event and triggers a motivation to avoid the source of conflict. In the present study, we tested this assumption. Over five experiments, we examined whether conflict is associated with an avoidance motivation and whether stimulus conflict or response conflict triggers an avoidance tendency. Participants first performed a color Stroop task. In a subsequent motivation test, participants responded to Stroop stimuli with approach- and avoidance-related lever movements. These results showed that Stroop-conflict stimuli increased the frequency of avoidance responses in a free-choice motivation test, and also increased the speed of avoidance relative to approach responses in a forced-choice test. High and low proportions of response conflict in the Stroop task had no effect on avoidance in the motivation test. Avoidance of conflict was, however, obtained even with new conflict stimuli that had not been presented before in a Stroop task, and when the Stroop task was replaced with an unrelated filler task. Taken together, these results suggest that stimulus conflict is sufficient to trigger avoidance. PMID:25931151

  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. Comparison of elemental contents in earthworm cast and soil from a mercury-contaminated site (Idrija area, Slovenia).

    PubMed

    Teršič, Tamara; Gosar, Mateja

    2012-07-15

    The aim of this paper was to test the new sampling media-earthworm casts in a highly contaminated area. The investigation was carried out at the ancient Hg ore roasting site Pšenk in the surroundings of Idrija, where extremely high Hg contents in soils and SOM were determined in previous investigations. 32 earthworm cast samples were collected in the research grid 30 × 30 m in order to compare the Hg contents and spatial distribution in earthworm casts to the values and distributions in SOM and soil (0-15 cm). Extremely elevated Hg concentrations were determined in earthworm casts from the studied area ranging from 5.4 to 4330 mg/kg with the median of 31 mg/kg. The Hg values in casts are somewhat lower than in soil (6.3-8600 mg/kg) and slightly higher compared to soil organic matter (SOM) (1.5-4200 mg/kg). Strong correlation (r²=0.75) between Hg contents in casts and soil was found, while correlation between casts and SOM was positive but weaker (r²=0.35). Spatial distribution of Hg in earthworm casts show the highest concentrations in the central part of investigated area, similar to the distribution in soil. Hg contents rapidly decrease from the center toward the margins of the studied area, where they reach values of less than 50mg/kg. It was shown that Hg contents and dispersion in casts are comparable to those in soil, which indicates that at investigated area soil contamination is strongly reflected in contamination of earthworm casts. PMID:22613464

  19. Association of Earthworm-Denitrifier Interactions with Increased Emission of Nitrous Oxide from Soil Mesocosms Amended with Crop Residue▿ †

    PubMed Central

    Nebert, Lucas D.; Bloem, Jaap; Lubbers, Ingrid M.; van Groenigen, Jan Willem

    2011-01-01

    Earthworm activity is known to increase emissions of nitrous oxide (N2O) from arable soils. Earthworm gut, casts, and burrows have exhibited higher denitrification activities than the bulk soil, implicating priming of denitrifying organisms as a possible mechanism for this effect. Furthermore, the earthworm feeding strategy may drive N2O emissions, as it determines access to fresh organic matter for denitrification. Here, we determined whether interactions between earthworm feeding strategy and the soil denitrifier community can predict N2O emissions from the soil. We set up a 90-day mesocosm experiment in which 15N-labeled maize (Zea mays L.) was either mixed in or applied on top of the soil in the presence or absence of the epigeic earthworm Lumbricus rubellus and/or the endogeic earthworm Aporrectodea caliginosa. We measured N2O fluxes and tested the bulk soil for denitrification enzyme activity and the abundance of 16S rRNA and denitrifier genes nirS and nosZ through real-time quantitative PCR. Compared to the control, L. rubellus increased denitrification enzyme activity and N2O emissions on days 21 and 90 (day 21, P = 0.034 and P = 0.002, respectively; day 90, P = 0.001 and P = 0.007, respectively), as well as cumulative N2O emissions (76%; P = 0.014). A. caliginosa activity led to a transient increase of N2O emissions on days 8 to 18 of the experiment. Abundance of nosZ was significantly increased (100%) on day 90 in the treatment mixture containing L. rubellus alone. We conclude that L. rubellus increased cumulative N2O emissions by affecting denitrifier community activity via incorporation of fresh residue into the soil and supplying a steady, labile carbon source. PMID:21515716

  20. 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...

  1. 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

  2. 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 clear that elevated N2O-emissions due to earthworm activity is a widespread phenomenon, and that the nature of earthworm-induced effect is largely controlled by its feeding habit and interactions with other species. Our results contribute to understanding the important but intricate relations between (functional) biodiversity and the soil greenhouse gas balance.

  3. 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

  4. 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.

  5. 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 signature and C and N contents converged towards those of the control soil. The first two axes of the PCA corresponded closely to the C and N content, respectively, of the casts. These two complementary experiments demonstrate that NIRS allows identifying origins of macroaggregates produced by various earthworm species in different environments. Other complementary experiences we realized in laboratory conditions highlight that OM modifications, caused in aging casts, are large enough to be detected by NIRS in macroaggregates and to estimate a cast's age. We propose a new method to analyse soil macroaggregates origins, to quantify the relative contribution of ecosystem engineers to soil aggregation and to evaluate soil macroaggregates dynamics in the soil structure.

  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. Our results may indicate a recurrent event in invasive earthworms within their ancestral distribution areas in the Western Palearctic. PMID:26299880

  7. [Effects of imidazolium chloride ionic liquids on the acute toxicity and weight of earthworm].

    PubMed

    Huang, Ruo-Nan; Fan, Jun-Jie; Tu, Hong-Zhi; Tang, Ling-Yan; Liu, Hui-Jun; Xu, Dong-Mei

    2013-04-01

    Standard contact filter paper test of OECD and artificial soil test were used to study the acute lethal effect of three imidazolium chloride ionic liquids, 1-butyl- 3-methylimidazolium chloride ([Bmim] Cl), 1-hexyl- 3-methylimidazolium chloride ([Hmim] Cl), and 1-octyl- 3-methylimidazolium chloride ([Omim] Cl) on earthworm (Eisenia fetida), and the weight of the earthworms was measured after subtle exposure. The 24 h-LC50 values of [Bmim] Cl, [Hmim] Cl and [Omim] Cl using the contact filter paper method were 109.60, 50.38 and 7.94 microg x cm(-2), respectively. The 48 h-LC50 values were 98.52, 39.14 and 3.61 microg x cm(-2), respectively. Using the artificial soil method, the 7 d-LC50 values of [Bmim] Cl, [Hmim] Cl and [Omim] Cl were 447.78, 245.56 and 180.51 mg x kg(-1), respectively, and the 14 d-LC50 values were 288.42, 179.75, 150.35 mg x kg(-1), respectively. There were differences in poisoning symptoms of the three ionic liquids on earthworms. The growth of Eisenia fetida was inhibited and declined with increasing ionic liquid concentration. The toxicity of ionic liquids on Eisenia fetida increased with the length of carbon chain. PMID:23798118

  8. 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

  9. 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

  10. 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 significantly enhanced rate and deeper reach of soil mixing at the invaded site. We are currently extending the measurements of carbon, specific surface area, and 210Pb activities to the seven soil pits along the entire length of the transect. This growing data set, when ultimately combined with ongoing monitoring of (1) the population dynamics of earthworms along the transect and (2) dissolved organic carbon, will allow us to answer how and how much soils’ capacity to store carbon are affected by burrowing organisms who are often the key stone species of given ecosystems.

  11. Earthworm Egg Capsules as Vectors for the Environmental Introduction of Biodegradative Bacteria

    PubMed Central

    Daane, L. L.; Häggblom, M. M.

    1999-01-01

    Earthworm egg capsules (cocoons) may acquire bacteria from the environment in which they are produced. We found that Ralstonia eutropha (pJP4) can be recovered from Eisenia fetida cocoons formed in soil inoculated with this bacterium. Plasmid pJP4 contains the genes necessary for 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4-dichlorophenol (2,4-DCP) degradation. In this study we determined that the presence of R. eutropha (pJP4) within the developing earthworm cocoon can influence the degradation and toxicity of 2,4-D and 2,4-DCP, respectively. The addition of cocoons containing R. eutropha (pJP4) at either low or high densities (102 or 105 CFU per cocoon, respectively) initiated degradation of 2,4-D in nonsterile soil microcosms. Loss of 2,4-D was observed within the first week of incubation, and respiking the soil with 2,4-D showed depletion within 24 h. Microbial analysis of the soil revealed the presence of approximately 104 CFU R. eutropha (pJP4) g−1 of soil. The toxicity of 2,4-DCP to developing earthworms was tested by using cocoons with or without R. eutropha (pJP4). Results showed that cocoons containing R. eutropha (pJP4) were able to tolerate higher levels of 2,4-DCP. Our results indicate that the biodegradation of 2,4-DCP by R. eutropha (pJP4) within the cocoons may be the mechanism contributing to toxicity reduction. These results suggest that the microbiota may influence the survival of developing earthworms exposed to toxic chemicals. In addition, cocoons can be used as inoculants for the introduction into the environment of beneficial bacteria, such as strains with biodegradative capabilities. PMID:10347016

  12. Vermistabilization of textile mill sludge spiked with poultry droppings by an epigeic earthworm Eisenia foetida.

    PubMed

    Garg, V K; Kaushik, Priya

    2005-06-01

    Investigations were made to explore the potential of an epigeic earthworm Eisenia foetida to transform textile mill sludge spiked with poultry droppings in to value added product, i.e., vermicompost. The growth and reproduction of E. foetida was monitored in a range of different feed mixtures for 77 days in the laboratory under controlled experimental conditions. The maximum growth was recorded in 100% cow dung (CD). Replacement of poultry droppings by cow dung in feed mixtures and vice versa had little or no effect on worm growth rate and reproduction potential. Worms grew and reproduced favourably in 70% poultry droppings (PD)+30% solid textile mill sludge (STMS) and 60% PD+40% STMS feed mixtures. Greater percentage of STMS in the feed mixture significantly affected the biomass gain and cocoon production. Net weight gain by earthworms in 100% CD was 2.9-18.2 fold higher than different STMS containing feed mixtures. The mean number of cocoon production was between 23.4+/-4.65 (in 100% CD) and 3.6+/-1.04 (in 50% PD+50% STMS) cocoons earthworm(-1) for different feed mixtures tested. Vermicomposting resulted in significant reduction in C:N ratio and increase in nitrogen and phosphorus contents. Total potassium, total calcium and heavy metals (Fe, Zn, Pb and Cd) contents were lower in the final product than initial feed mixtures. Our trials demonstrated vermicomposting as an alternate technology for the recycling and environmentally safe disposal/management of textile mill sludge using an epigeic earthworm E. foetida if mixed with poultry droppings. PMID:15668203

  13. Enantiomer-specific toxicity and bioaccumulation of alpha-cypermethrin to earthworm Eisenia fetida.

    PubMed

    Diao, Jinling; Xu, Peng; Liu, Donghui; Lu, Yule; Zhou, Zhiqiang

    2011-09-15

    Alpha-cypermethrin, a synthetic pyrethroid, is highly effective against a wide range of chewing and sucking insects in crops, and it is a racemic mixture of two enantiomers ((+)-1R-cis-?S+(-)-1S-cis-?R). Studies about the toxicity of alpha-cypermethrin to non-target organisms are mainly focused on aquatic organisms, whereas information regarding terrestrial organisms is relatively much less. Very little report about its enantioselective toxicity is known, so the present study tested the enantiomer-specific acute toxicity to earthworm Eisenia fetida. Experiment about bioaccumulation of two enantiomers in soil was conducted, peak-shaped accumulation curves were observed for both enantiomers, and the calculated biota to soil accumulations factor (BSAF) have significant difference between the two enantiomers. It was obvious that earthworm can uptake alpha-cypermethrin enantioselectively, preferentially accumulating (-)-(1S-cis-?R)-enantiomer. Great difference in toxicity to earthworm between two enantiomers was found, and the calculated LC(50) values for (+)-(1R-cis-?S)-, (-)-(1S-cis-?R)-, and rac-alpha-cypermethrin were 49.53, 1663.87 and 165.61 ng/cm(2), respectively. The acute toxicity of alpha-cypermethrin enantiomers was enantioselective. PMID:21724328

  14. 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.

  15. 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

  16. Parametric studies of antipsychotic-induced sensitization in the conditioned avoidance response model: roles of number of drug exposure, drug dose, and test–retest interval

    PubMed Central

    Swalve, Natashia; Li, Ming

    2016-01-01

    Repeated haloperidol and olanzapine treatment produces an enhanced disruption of avoidance responding, a validated measure of antipsychotic activity. Experimental parameters affecting this sensitization-like effect have not been thoroughly examined. The present study investigated the role of three parameters (number of injections, dose, and interval between initial exposure and challenge) in antipsychotic sensitization in the conditioned avoidance response paradigm. Well-trained Sprague–Dawley rats received different numbers of drug treatment (1–5 days) or different doses of haloperidol (0.025–0.10 mg/kg, subcutaneously) or olanzapine (0.5–2.0 mg/kg, subcutaneously). After certain time intervals (4, 10 or 17 days), they were tested for the expression of haloperidol or olanzapine sensitization in a challenge test in which all rats were injected with a lower dose of haloperidol (0.025 mg/kg) or olanzapine (0.5 mg/kg). Throughout the drug-treatment period, both haloperidol and olanzapine dose-dependently enhanced their disruption of avoidance responding. Three days later, the sensitization induced by a low dose of haloperidol (0.025 mg/kg) or olanzapine (0.5 mg/kg) was only apparent in rats that received treatment for 5 days, but not in those that received treatment for 1–4 days. The sensitization induced by the medium and high doses of haloperidol (0.05 and 0.10 mg/kg) or olanzapine (1.0 and 2.0 mg/kg) was still robust even with only 3 days of treatment. The sensitization induced by a 3-day haloperidol (0.10 mg/kg) and olanzapine (2.0 mg/kg) treatment was long-lasting, still detectable 17 days after the last drug treatment. This study suggests that antipsychotic sensitization is a robust behavioral phenomenon. Its induction and expression are strongly influenced by parameters such as number of drug exposures, drug dose, and test–retest interval. Given the importance of antipsychotic sensitization in the maintenance of antipsychotic effects in the clinic, this study introduces a paradigm that can be used to investigate the behavioral and neurobiological mechanisms underlying antipsychotic sensitization. PMID:22732209

  17. 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

  18. 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.

  19. 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

  20. 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

  1. 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

  2. Effects of 7-NI and ODQ on memory in the passive avoidance, novel object recognition, and social transmission of food preference tests in mice

    PubMed Central

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

    2014-01-01

    Background Nitric oxide (NO) is an intercellular messenger that plays a critical role in learning and memory processes. Effects of nitric oxide synthase (NOS) inhibitors and guanylate cyclase (GC) inhibitors on cognitive function remain controversial. Material/Methods The aim of this study was to investigate effects of an NOS inhibitor, 7-nitroindazole (7-NI), and a GC inhibitor, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), on different aspects of memory in passive avoidance (PA), novel object recognition (NOR), and social transmission of food preference (STFP) tests. Male Balb-c mice were treated intraperitoneally with 7-NI (15 mg/kg), ODQ (3,10 mg/kg), L-arginine (100 mg/kg) + 7-NI (15 mg/kg), or physiological saline. Results ODQ (10 mg/kg) and 7-NI (15 mg/kg) significantly decreased second-day latency in PA test. 7-NI (15 mg/kg) and ODQ (10 mg/kg) significantly decreased the ratio index in the NOR test. 7-NI and ODQ (10 mg/kg) decreased cued/non-cued food eaten in STFP test. Amount of time spent in center zone significantly increased in ODQ (10 mg/kg) and 7-NI (15 mg/kg) groups in open field test, but there was no effect on total distance moved and speed of animals. ODQ (10 mg/kg) significantly increased number of entries into new compartments in exploratory activity apparatus, while 7-NI had no effect. Administration of L-arginine (100 mg/kg) before 7-NI reversed 7-NI-induced effects, supporting the role of NO in cognition. Conclusions Our results confirm that inhibition of NO/cGMP/GS pathway might disturb emotional, visual, and olfactory memory in mice. Also, 7-NI and ODQ had anxiolytic effects in open field test, and ODQ also enhanced exploratory activity. PMID:24643075

  3. A global survey of the bacteria within earthworm nephridia.

    PubMed

    Davidson, Seana K; Powell, Ryan; James, Sam

    2013-04-01

    Earthworms comprise 16 described families in the Crassiclitellata plus a few other minor groups. Microscopy studies of the early 20th century detected bacteria within the excretory organs, the nephridia, of species within a few of these families. More recent evidence for the consistent and specific association of bacteria with nephridia within the Lumbricidae has been well documented, but the presence and identity of nephridial bacteria among the rest of the Crassiclitellata families had not been explored. The study presented here aimed to identify members of Crassiclitellata families that harbor bacteria in their nephridia, and identify these bacteria based on 16S rRNA gene sequences. Eleven earthworm families were surveyed from countries of six continents, and two island nations. The results revealed members of four bacterial orders commonly occurred within nephridia of genera within nine Crassiclitellata families. Members of the bacterial phyla Bacteroidetes (order Sphingobacteriales), Betaproteobacteria (order Burkholderiales; family Comamonadaceae), and Alphaproteobacteria (orders Rhodospirillales and Rhizobiales) were detected in the nephridia of basal Crassiclitellata, as well as in derived families. Earthworm genera with meronephridia, multiple small nephridia per segment, lacked bacteria, whereas bacteria were often detected in holonephridia, single pairs of large nephridia with a distinct morphology and external excretory pore. The Acanthodrilidae members, a large derived family of earthworms, did not appear to possess nephridial bacteria regardless of nephridial form. Although earthworms from a variety of habitat types were sampled, there were no clear correlations of lifestyle with symbiont types, with the exception of the aquatic earthworms that contained bacteria unrelated to those in any other earthworms. The findings support an evolutionarily long association of bacteria within the Crassiclitellata, and suggest a contribution to nitrogen conservation for the earthworms. PMID:23268186

  4. Treating swine wastewater by integrating earthworms into constructed wetlands.

    PubMed

    Nuengjamnong, Chackrit; Chiarawatchai, Nathasith; Polprasert, Chongrak; Otterpohl, Ralf

    2011-01-01

    The aim of this study was to investigate the application of integrating earthworms (Pheretima peguana) into two-stage pilot-scale subsurface-flow constructed wetlands (SFCWs) receiving swine wastewater in terms of their treatment performance, namely organic content, total kjeldahl nitrogen (TKN), and solid reduction as well as the quantity of sludge production. There was a minor difference in terms of removal efficiency according to each parameter when comparing the unit with earthworms to the one without earthworms. Both achieved the TKN, biochemical oxygen demand (BOD), chemical oxygen demand (COD), total volatile suspended solids (TVSS), suspended solids (SS), and total solids (TS) removal by more than 90 %. The earthworms helped in reducing the sludge production on the surface of constructed wetlands 40 % by volume, which resulted in lowering operational costs required to empty and treat the sludge. The plant biomass production was higher in the wetlands without earthworms. Further research could be undertaken in order to effectively apply earthworms inside the wetlands. PMID:21644160

  5. 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

  6. 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

  7. 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 extractable using cyclodextrin. Hence, while cyclodextrin extraction may serve as a good proxy for microbial bioavailability, our results suggest that it may not serve as a good proxy for earthworm bioavailability. 1H NMR metabolomics therefore offers considerable promise as a novel, molecular-level method to directly monitor earthworm bioavailability of potentially toxic and persistent compounds in the environment.

  8. 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

  9. 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

  10. 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,...

  11. 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.

  12. 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

  13. 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-citrate extractable Fe and Al, which may help stabilize organic matter and may impede chemical weathering of minerals by coating their reactive surfaces. We expect that the behavior of a given element will be based upon its biological demand, complexation with organic matter, and hydrological mobility. Understanding how quickly and what extent various elements are mixed by invasive earthworms will help determine the magnitude of invasive earthworms' impact on the future nutrient cycles in hardwood forests.

  14. Behavioral methods for the study of the Ras-ERK pathway in memory formation and consolidation: passive avoidance and novel object recognition tests.

    PubMed

    d'Isa, Raffaele; Brambilla, Riccardo; Fasano, Stefania

    2014-01-01

    Memory is a high-level brain function that enables organisms to adapt their behavioral responses to the environment, hence increasing their probability of survival. The Ras-ERK pathway is a key molecular intracellular signalling cascade for memory consolidation. In this chapter we will describe two main one-trial behavioral tests commonly used in the field of memory research in order to assess the role of Ras-ERK signalling in long-term memory: passive avoidance and object recognition. Passive avoidance (PA) is a fear-motivated instrumental learning task, designed by Jarvik and Essman in 1960, in which animals learn to refrain from emitting a behavioral response that has previously been associated with a punishment. We will describe here the detailed protocol and show some examples of how PA can reveal impairments or enhancements in memory consolidation following loss or gain of function genetic manipulations of the Ras-ERK pathway. The phenotypes of global mutants as Ras-GRF1 KO, GENA53, and ERK1 KO mice, as well as of conditional region-specific mutants (striatal K-CREB mice), will be illustrated as examples. Novel object recognition (NOR), developed by Ennaceur and Delacour in 1988, is instead a more recent and highly ecological test, which relies on the natural tendency of rodents to spontaneously approach and explore novel objects, representing hence a useful non-stressful tool for the study of memory in animals without the employment of punishments or starvation/water restriction regimens. Careful indications will be given on how to select the positions for the novel object, in order to counterbalance for individual side preferences among mice during the training. Finally, the methods for calculating two learning indexes will be described. In addition to the classical discrimination index (DI) that measures the ability of an animal to discriminate between two different objects which are presented at the same time, we will describe the formula of a new index that we present here for the first time, the recognition index (RI), which quantifies the ability of an animal to recognize a same object at different time points and that, by taking into account the basal individual preferences displayed during the training, can give a more accurate measure of an animal's actual recognition memory. PMID:24470023

  15. EARTHWORM ADDITIONS AFFECT LEACHATE PRODUCTION AND NITROGEN LOSSES IN TYPICAL MIDWESTERN AGROECOSYSTEMS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Earthworms affect soil structure and the movement of agrochemicals. Yet, there are few field-scale studies that quantify the effect of earthworms on dissolved nitrogen fluxes in agroecosystems. We investigated the influence of biannual deep-burrowing earthworm additions on leachate production and qu...

  16. 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

  17. 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.

  18. 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.

  19. 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 earthworms affect not only C concentration but also soil bulk density and A horizon thickness. Mineral's SSA in the A and E is significantly larger and greater portions of the mineral SSA are coated with C in soils with greater earthworm biomass. These results show that both mineral's capacity to complex C and the actual complexation are enhanced by earthworm invasion presumably because earthworms' ability to vertically mix soils. This growing data set will ultimately elucidate how soils' capacity to stabilize C is influenced by exotic earthworm species.

  20. 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

  1. 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.

  2. 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

  3. 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.

  4. 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

  5. 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.

  6. 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

  7. 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 ...

  8. 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 Octolasion cyaneum. Five out of these eight species are relevant for each biogeographical region with an overlap in the species. Finally, the earthworm species Ap. caliginosa (endogeic, secondary decomposer) and L. terrestris (anecic, primary decomposer) were selected as focal species. In the Mediterranean region L. terrestris may be substituted by the more relevant anecic species L. friendi. The selected focal species are recommended to be included in a standardized laboratory ERA test system based on life-history traits. PMID:26803734

  9. 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.

  10. 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 extractions or sequential extractions with bioaccumulations. Finally, we discussed the advantages or disadvantages of simple chemical extractions which are commonly used to estimate the efficacy of stabilization.

  11. 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

  12. 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

  13. 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

  14. 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.

  15. 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

  16. 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

  17. 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

  18. 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.

  19. Genotoxic effects of glyphosate or paraquat on earthworm coelomocytes.

    PubMed

    Muangphra, Ptumporn; Kwankua, Wimon; Gooneratne, Ravi

    2014-06-01

    The potential genotoxicity (nuclear anomalies, damage to single-strand DNA) and pinocytic adherence activity of two (glyphosate-based and paraquat-based) commercial herbicides to earthworm coelomocytes (immune cells in the coelomic cavity) were assessed. Coelomocytes were extracted from earthworms (Pheretima peguana) exposed to concentrations earthworms exposed to glyphosate at 25 × 10(-1) (10(-3) LC50) and paraquat at 39 × 10(-5) (10(-4) LC50) ?g cm(-2) filter paper. In earthworms exposed to glyphosate, no differences in tail DNA%, tail length, and tail moment of coelomocytes were detected. In contrast, for paraquat at 10(-1) LC50 concentration, there were significant (P < 0.05) differences between tail DNA % and tail length, and at LC50 concentration, tail moment was also significantly different when compared with controls. A decline in pinocytic adherence activity in coelomocytes occurred on exposure to glyphosate or paraquat at 10(-3) LC50 concentration. This study showed that, at concentrations well below field application rates, paraquat induces both clastogenic and aneugenic effects on earthworm coelomocytes whereas glyphosate causes only aneugenic effects and therefore does not pose a risk of gene mutation in this earthworm. PMID:22644885

  20. 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.

  1. 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 forest conditions and identify uninvaded areas that could serve as important refugia for plant species threatened by earthworm invasion. PMID:17913131

  2. 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 interacting with standardized trained patient actors enacting the clinical scenario of counseling for pre-diabetes, each of whom had a pedometer that recorded the number of steps taken over a week. In both phases, all sessions were audio-taped and motion screen-capture software was activated for onscreen recordings. Transcripts were coded using iterative qualitative content analysis methods. Results In Phase I, the impact of the components and layout of ADAPT on user’s Navigation, Understandability, and Workflow were associated with the largest volume of negative comments (i.e. approximately 80% of end-user commentary), while Usability and Content of ADAPT were representative of more positive than negative user commentary. The heuristic category of Usability had a positive-to-negative comment ratio of 2.1, reflecting positive perception of the usability of the tool, its functionality, and overall co-productive utilization of ADAPT. However, there were mixed perceptions about content (i.e., how the information was displayed, organized and described in the tool). In Phase II, the duration of patient encounters was approximately 10 minutes with all of the Patient Instructions (prescriptions) and behavioral contracting being activated at the end of each visit. Upon activation, providers accepted the pathway prescribed by the tool 100% of the time and completed all the fields in the tool in the simulation cases. Only 14% of encounter time was spent using the functionality of the ADAPT tool in terms of keystrokes and entering relevant data. The rest of the time was spent on communication and dialogue to populate the patient instructions. In all cases, the interaction sequence of reviewing and discussing exercise and diet of the patient was linked to the functionality of the ADAPT tool in terms of monitoring, response-efficacy, self-efficacy, and negotiation in the patient-provider dialogue. There was a change from one-way dialogue to two-way dialogue and negotiation that ended in a behavioral contract. This change demonstrated the

  3. Food Avoidance Diets for Dermatitis.

    PubMed

    Scott, Jeffrey F; Hammond, Margaret I; Nedorost, Susan T

    2015-10-01

    Food allergy is relatively common in both children and adults, and its prevalence is increasing. Early exposure of food allergens onto skin with an impaired epidermal barrier predisposes to sensitization and prevents the development of oral tolerance. While immediate-type food allergies are well described, less is known about delayed-type food allergies manifesting as dermatitis. This is due, in part, to limitations with current diagnostic testing for delayed-type food allergy, including atopy patch testing. We conducted a systematic review of food avoidance diets in delayed-type food allergies manifesting as dermatitis. While beneficial in some clinical circumstances, avoidance diets should be used with caution in infants and children, as growth impairment and developmental delay may result. Ultimately, dermatitis is highly multifactorial and avoidance diets may not improve symptoms of delayed-type food allergy until combined with other targeted therapies, including restoring balance in the skin microbiome and re-establishing proper skin barrier function. PMID:26300528

  4. 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

  5. Acute toxicity, biochemical and gene expression responses of the earthworm Eisenia fetida exposed to polycyclic musks.

    PubMed

    Chen, Chun; Zhou, Qixing; Liu, Shuo; Xiu, Zongming

    2011-05-01

    AHTN (Tonalide) and HHCB (galaxolide) are recognized as ubiquitous contaminants in soil and have potential adverse impacts on soil organisms. The aim of this study is to investigate the effects of AHTN and HHCB on the earthworm (Eisenia fetida) as an important soil animal with attention to the acute toxicity, biochemical and transcriptional changes of representative antioxidant enzymatic (SOD, CAT) and stress-response gene (Hsp70). The 48 h-LC(50) value was 20.76 μg cm(-2) for AHTN and 11.87 μg cm(-2) for HHCB respectively in the acute lethal studies. The time-dependent elevation in the level of malondialdehyde (MDA) suggests that reactive oxygen species (ROS)-induced cellular oxidative injury of E. fetida might be one of the main toxic effects of AHTN and HHCB. SOD and CAT were both up-regulated at low exposure dose (0.6 μg cm(-2) AHTN and 0.3 μg cm(-2) HHCB) during 48 h testing period, which protected earthworms from oxidative stresses. However, the down-regulation of SOD and CAT after 48 h exposure to high dose contaminants might be caused by the extreme oxidative stress levels (maximum up-regulation 1.70-fold and 1.40-fold for MDA levels at 6.0 μg cm(-2) AHTN and 3.0 μg cm(-2) HHCB compared to the controls, respectively). The Hsp70 gene expression did not show variation during 48 h, except that it had a significant down-regulation (P<0.05) after 48 h of exposure to high doses of contaminants. These results showed that the dermal contact of AHTN and HHCB could result in pronounced biochemical and physiological responses to earthworms, and the transcriptional level changes in antioxidant genes could be potential molecular biomarkers for the stress of the pollutants. PMID:21281957

  6. 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.

  7. 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

  8. 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 measure completion. Secondary patient outcomes include disability, pain, fear of movement, mood, quality of life, and global recovery. Outcomes are measured at three and six months post-randomisation. Discussion This paper details the rationale, design, therapist training system and recruitment methods to be used in a feasibility study which will inform the design and efficient implementation of a future definitive RCT. Trial registration ISRCTN43733490 PMID:23764140

  9. 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…

  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. 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

  13. Indication of metal homeostasis disturbance in earthworm Eisenia fetida after exposure to semi-solid depot sludge.

    PubMed

    Babić, Sanja; Dragun, Zrinka; Sauerborn Klobučar, Roberta; Ivanković, Dušica; Bačić, Niko; Fiket, Željka; Barišić, Josip; Krasnići, Nesrete; Strunjak-Perović, Ivančica; Topić Popović, Natalija; Čož-Rakovac, Rozelindra

    2015-09-01

    Treated sewage sludge is commonly used in agriculture as fertilizer. It is, therefore, necessary to determine possible detrimental influences of sludge application on soil contamination and accumulation of contaminants in tissues of terrestrial animals, which in the long run could also have undesirable effects on humans. With that aim, the study was performed using earthworm Eisenia fetida as test organism and semi-solid depot sludge from a wastewater treatment plant as exposure media. The concentrations of 26 metals/metalloids were determined in depot sludge, and their bioaccumulation was estimated in whole tissue of E. fetida, and for the first time in the soluble tissue fraction, which represents metal fraction available for metabolic requirements and toxic effects. Obtained results have revealed acceptable levels of several elements (Cd, Cr, Cu, Ni, Pb, Zn) in depot sludge, when compared to currently valid regulations, and only moderate accumulation of some elements (e.g. As, Ba, Cd, Co, Fe, Tl, V, and Zn) in earthworms, as a consequence of exposure to depot sludge. However, a concentration increase after exposure to depot sludge was observed in E. fetida for several elements (Cd, Mo, and Zn), which were present in lower concentrations in the exposure mixtures than in soil. Contrary, a concentration decrease was observed for Cs, Mn, and Rb, although they were present in higher concentrations in depot sludge than in soil. It was an indication of disturbance in metal homeostasis in earthworms, possibly caused by exposure to complex mixture of contaminants present in depot sludge. The cumulative effect of exposure to a number of various contaminants (inorganic, organic, microbiological and pharmaceutical), even if each of them was not present in very high concentrations, could have caused distress in earthworms exposed to depot sludge. PMID:25931022

  14. {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.

  15. Nitrous Oxide Reductase Genes (nosZ) of Denitrifying Microbial Populations in Soil and the Earthworm Gut Are Phylogenetically Similar†

    PubMed Central

    Horn, Marcus A.; Drake, Harold L.; Schramm, Andreas

    2006-01-01

    Earthworms emit nitrous oxide (N2O) and dinitrogen (N2). It has been hypothesized that the in situ conditions of the earthworm gut activates ingested soil denitrifiers during gut passage and leads to these in vivo emissions (M. A. Horn, A. Schramm, and H. L. Drake, Appl. Environ. Microbiol. 69:1662-1669, 2003). This hypothesis implies that the denitrifiers in the earthworm gut are not endemic to the gut but rather are regular members of the soil denitrifier population. To test this hypothesis, the denitrifier populations of gut and soil from three different sites were comparatively assessed by sequence analysis of nosZ, the gene for the terminal enzyme in denitrification, N2O reductase. A total of 182 and 180 nosZ sequences were retrieved from gut and soil, respectively; coverage of gene libraries was 79 to 100%. Many of the nosZ sequences were heretofore unknown, clustered with known soil-derived sequences, or were related to N2O reductases of the genera Bradyrhizobium, Brucella, Dechloromonas, Flavobacterium, Pseudomonas, Ralstonia, and Sinorhizobium. Although the numbers of estimators for genotype richness of sequence data from the gut were higher than those of soil, only one gut-derived nosZ sequence did not group phylogenetically with any of the soil-derived nosZ sequences. Thus, the phylogenies of nosZ from gut and soil were not dissimilar, indicating that gut denitrifiers are soil derived. PMID:16461644

  16. Partitioning of habitable pore space in earthworm burrows

    PubMed Central

    Amador, Jose A.

    2010-01-01

    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, Vs, 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 Vs 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

  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. 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...

  20. 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...

  1. 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...

  2. 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...

  3. 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)

  4. Cadmium and lead accumulation in three endogeic earthworm species.

    PubMed

    Latif, Robabeh; Malek, Masoumeh; Mirmonsef, Hassan

    2013-04-01

    The objective of this study was to assess the capability of earthworms from the same ecological group as heavy metal bioindicators. Three earthworm species from the endogeic group were studied: Aporrectodea caliginosa (Savigny, 1826), Perelia kaznakovi (Michaelsen, 1910) and Octolasion lacteum (Örley, 1885). Their accumulation of the heavy metals lead (Pb) and cadmium (Cd) were studied from three stations in Tehran province, Iran. O. lacteum was used to compare metal accumulations in two sites located next to a highway. A. caliginosa and P. kaznakovi were used at a third site located near the edge of a sewage system to compare metal accumulations between the two endogeic species in this area. At both locations, the concentrations of Cd and Pb in earthworms were higher than in the surrounding soil. The results of the study revealed that P. kaznakovi and A. caliginosa were better bioindicators for Pb, but O. lacteum was a better bioindicator for Cd. These earthworms can therefore be used as Cd and Pb bioindicators in environmental assessment. PMID:23283534

  5. 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…

  6. 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

  7. 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

  8. 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.

  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. Distribution of bacteria and fungi in the earthworm Libyodrillus violaceous (Annelida: Oligochaeta), a native earthworm from Nigeria.

    PubMed

    Idowu, A B; Edema, M O; Adeyi, A O

    2006-03-01

    Earthworms are soil invertebrates that play a key role in recycling organic matter in soils. In Nigeria, earthworms include Libyodrillus violaceous. Aerobic and anaerobic bacterial counts, as well as fungal counts of viable microorganisms in soils and gut sections, were made on twenty L. violaceous collected from different sites on the campus of the University of Agriculture, Abeokuta, Nigeria. The samples were collected between April and November, 2002. Numbers of microorganisms were higher in castings and gut sections than in un-ingested soil samples. The guts and their contents also had higher moisture and total nitrogen contents than the un-ingested soils. Bacteria and fungi isolated from the samples were identified by standard microbiological procedures on the bases of their morphological and biochemical characteristics. Isolated bacteria were identified as Staphylococcus, Bacillus spp., Pseudomonas aeruginosa, Streptococcus mutans, Clostridium, Spirocheata spp., Azotobacter spp., Micrococcus lylae, Acinetobacter spp., Halobacterium for bacteria. Yeast isolates were identified as Candida spp., Zygosaccharomyces spp., Pichia spp., and Saccharomyces spp while molds were identified as, Aspergillus spp., Pytium spp., Penicillium spp., Fusarium spp and Rhizopus spp. Of the five locations examined, the refuse dump area had the highest numbers of both aerobic and anaerobic organisms, followed by the arboretum while the cultivated land area recorded the lowest counts. The higher numbers of microorganisms observed in the gut sections and casts of the earthworms examined in this work reinforce the general concept that the gut and casts of earthworms show higher microbial diversity and activity than the surrounding soil. PMID:18457174

  11. 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

  12. Toxicity of AMPA to the earthworm Eisenia andrei Bouché, 1972 in tropical artificial soil.

    PubMed

    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

  13. 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

  14. A review of studies performed to assess metal uptake by earthworms.

    TOXLINE Toxicology Bibliographic Information

    Nahmani J; Hodson ME; Black S

    2007-01-01

    Earthworms perform a number of essential functions in soil; the impacts of metals on earthworms are often investigated. In this review we consider the range of earthworm species, types of soil and forms of metal for which metal uptake and accumulation have been studied, the design of these experiments and the quantitative relationships that have been derived to predict earthworm metal body burden. We conclude that there is a need for more studies on earthworm species other than Eisenia fetida in order to apply the large existing database on this earthworm to other, soil dwelling species. To aid comparisons between studies agreement is needed on standard protocols that define exposure and depuration periods and the parameters, such as soil solution composition, soil chemical and physical properties to be measured. It is recommended that more field or terrestrial model ecosystem studies using real contaminated soil rather than metal-amended artificial soils are performed.

  15. A review of studies performed to assess metal uptake by earthworms.

    PubMed

    Nahmani, Johanne; Hodson, Mark E; Black, Stuart

    2007-01-01

    Earthworms perform a number of essential functions in soil; the impacts of metals on earthworms are often investigated. In this review we consider the range of earthworm species, types of soil and forms of metal for which metal uptake and accumulation have been studied, the design of these experiments and the quantitative relationships that have been derived to predict earthworm metal body burden. We conclude that there is a need for more studies on earthworm species other than Eisenia fetida in order to apply the large existing database on this earthworm to other, soil dwelling species. To aid comparisons between studies agreement is needed on standard protocols that define exposure and depuration periods and the parameters, such as soil solution composition, soil chemical and physical properties to be measured. It is recommended that more field or terrestrial model ecosystem studies using real contaminated soil rather than metal-amended artificial soils are performed. PMID:16815606

  16. 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

  17. 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.

  18. 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.

  19. New earthworm records from Turkey, with description of three new species (Oligochaeta: Lumbricidae).

    PubMed

    Szederjesi, Tímea; Pavlí?ek, Tomás; Co?kun, 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

  20. 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.

  1. 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

  2. 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

  3. 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, type?pyrethroid) and lambad-cyhalothrin (LCT, type ? 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 (Koc) 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 BSAFS and Log Kow was observed, and the Log BSAFS decreased with the increase of Log Kow. PMID:26490429

  4. EPR detection of hydroxyl radical generation and oxidative perturbations in lead-exposed earthworms (Eisenia fetida) in the presence of decabromodiphenyl ether.

    PubMed

    Liu, Kou; Chen, Lin; Zhang, Wei; Lin, Kuangfei; Zhao, Li

    2015-03-01

    Lead (Pb) and decabromodiphenyl ether (BDE209) are the main contaminants at e-waste recycling sites, and their potential toxicological effects on terrestrial organisms have received extensive attention. However, the impacts on the oxidative perturbations and hydroxyl radical (·OH) generation in earthworms of exposure to the two chemicals remain almost unknown. Therefore, indoor incubation tests were performed on control and contaminated soil samples to determine the effects of Pb in earthworms Eisenia fetida in the presence of BDE209 through the use of several biomarkers in microcosms. The results have demonstrated that the addition of BDE209 (1 or 10 mg kg(-1)) decreased the enzymatic activities [superoxide dismutase, catalase (CAT), peroxidase] and total antioxidant capacity (T-AOC) compared with exposure to BDE209 alone (50, 250 or 500 mg kg(-1)). Electron paramagnetic resonance spectra indicated that ·OH radicals in earthworms were significantly induced by Pb in the presence of BDE209. The changing pattern of malondialdehyde (MDA) contents was accordant with that of ·OH intensity suggested that reactive oxygen species might lead to cellular lipid peroxidation. Furthermore, CAT exhibited more sensitive response to single Pb exposure than the other biomarkers, while T-AOC, ·OH and MDA might be three most sensitive biomarkers in earthworms after simultaneous exposure to Pb and BDE209. The results of these observations suggested that oxidative stress appeared in E. fetida, and it may play an important role in inducing the Pb and BDE209 toxicity to earthworms. PMID:25373545

  5. Gene expression analysis of CL-20-induced reversible neurotoxicity reveals GABA(A) receptors as potential targets in the earthworm Eisenia fetida.

    PubMed

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

    2012-01-17

    The earthworm Eisenia fetida is one of the most used species in standardized soil ecotoxicity tests. End points 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 apply 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/cm(2) 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 days 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 shotgun oligo array. Statistical and bioinformatic analyses suggest that CL-20 initiated neurotoxicity by noncompetitively blocking the ligand-gated GABA(A) 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

  6. 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-line. The optimal avoidance trajectory is implemented as a receding-horizon model predictive control law. Therefore, at each time step, the optimal avoidance trajectory is found and the first time step of its acceleration is applied. At the next time step of the control computer, the problem is re-solved and the new first time step is again applied. This continual updating allows the RCA algorithm to adapt to a colliding spacecraft that is making erratic course changes.

  7. Earthworm Is a Versatile and Sustainable Biocatalyst for Organic Synthesis

    PubMed Central

    Guan, Zhi; Chen, Yan-Li; Yuan, Yi; Song, Jian; Yang, Da-Cheng; Xue, Yang; He, Yan-Hong

    2014-01-01

    A crude extract of earthworms was used as an eco-friendly, environmentally benign, and easily accessible biocatalyst for various organic synthesis including the asymmetric direct aldol and Mannich reactions, Henry and Biginelli reactions, direct three-component aza-Diels-Alder reactions for the synthesis of isoquinuclidines, and domino reactions for the synthesis of coumarins. Most of these reactions have never before seen in nature, and moderate to good enantioselectivities in aldol and Mannich reactions were obtained with this earthworm catalyst. The products can be obtained in preparatively useful yields, and the procedure does not require any additional cofactors or special equipment. This work provides an example of a practical way to use sustainable catalysts from nature. PMID:25148527

  8. 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 coupling of chemical weathering and soil carbon cycle. Our ultimate goal is to understand the holistic response of mineral weathering and carbon cycle to accelerated soil mixing by earthworm invasion.

  9. Plasmid Transfer between Spatially Separated Donor and Recipient Bacteria in Earthworm-Containing Soil Microcosms.

    PubMed

    Daane, L L; Molina, J; Sadowsky, M J

    1997-02-01

    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 isolated bacteria in nonsterile soil, using burrowing earthworms as a biological factor to facilitate cell-to-cell contact. PMID:16535521

  10. 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 isolated bacteria in nonsterile soil, using burrowing earthworms as a biological factor to facilitate cell-to-cell contact. PMID:16535521

  11. 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 belowground-aboveground linkages involving earthworms and AMF are important mediators of the diversity, structure and functioning of plant communities. PMID:22216236

  12. 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 potential hazardous impacts for predatory animals in northeastern US forests and other ecosystems.

  13. 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...

  14. 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 ?18O 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. ?18O values were determined on individual calcite granules (?18Oc) and the soil solution (?18Ow). The ?18Oc values reflect soil solution ?18Ow 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 ? = [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.

  15. 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

  16. 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.

  17. 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.

  18. 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.

  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. 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...

  3. 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…

  4. 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…

  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. 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.

  7. 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 ...

  8. 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...

  9. 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...

  10. Subacute toxicity of copper and glyphosate and their interaction to earthworm (Eisenia fetida).

    PubMed

    Zhou, Chui-Fan; Wang, Yu-Jun; Li, Cheng-Cheng; Sun, Rui-Juan; Yu, Yuan-Chun; Zhou, Dong-Mei

    2013-09-01

    Glyphosate (GPS) and copper (Cu) are common pollutants in soils, and commonly co-exist. Due to the chemical structure of GPS, it can form complexes of heavy metals and interface their bioavailability in soil environment. In order to explore the interactions between GPS and Cu, subacute toxicity tests of Cu and GPS on soil invertebrate earthworms (Eisenia fetida) were conducted. The relative weight loss and whole-worm metal burdens increased significantly with the increasing exposure concentration of Cu, while the toxicity of GPS was insignificant. The joint toxicity data showed that the relative weight loss and the uptake of Cu, as well as the superoxide dismutase, catalase and malondialdehyde activities, were significantly alleviated in the present of GPS, which indicated that GPS could reduce the toxicity and bioavailability of Cu in the soil because of its strong chelating effects. PMID:23733011

  11. 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

  12. 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

  13. 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

  14. Earthworm responses to different reclamation processes in post opencast mining lands during succession.

    PubMed

    Hlava, Jakub; Hlavová, Anna; Hakl, Josef; Fér, Miroslav

    2015-01-01

    This study provides earthworm population data obtained from localities with a substantial anthropogenic impact spoils. The spoil heaps were reclaimed at the end of an opencast brown coal mining period. We studied spoils reclaimed by the two most commonly used reclamation processes: forestry and agricultural. The results show the significance of the locality age and the utilized reclamation process and treatment and their effect on earthworm communities. Our data indicate that apart from soil physical and chemical properties, the reclamation process itself may also induce viability and distribution of earthworm communities. Under standardized soil properties, the changes in earthworm populations during the succession were larger within the agricultural reclamation process as opposed to the forestry reclamation process for earthworm ecological groups and individual species. PMID:25380717

  15. 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

  16. 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.

  17. 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

  18. 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.

  19. [Polycyclic musks exposure affects gene expression of specific proteins in earthworm Eisenia fetida].

    PubMed

    Chen, Chun; Liu, Xiao-wei; Zheng, Shun-an; Zhou, Qi-xing; Li, Song

    2013-05-01

    To investigate the changes in gene expression of earthworm specific proteins following long-term exposure to low-dose polycyclic musks in soil, the mRNA expression levels of the four representative protein-coding genes (HSP70, CRT, cyPA, TCTP) were examined in earthworm Eisenia fetida exposed to polycyclic musks using real-time quantitative PCR (RT-qPCR). The purpose of this study was to investigate mRNA expression profiles of test protein genes in response to sublethal galaxolide (HHCB) and tonalide (AHTN) for 28 d exposure. The analysis results of both sequence alignment and melting curves of RT-qPCR reactions showed that the selected primers were appropriately qualified for quantitative mRNA analysis. mRNA expressions of HSP70 gene were not significantly changed in Eisenia fetida exposed to low concentrations of AHTN (less than 30 microg x g(-1)) and HHCB (less than 50 microg x g(-1)). But HSP70 gene expressions were significantly down-regulated at concentrations of AHTN or HHCB equal to or greater than 30 or 50 microg x g(-1). However, up-regulation of CRT gene expressions was induced in response to all test concentrations of AHTN and HHCB. Both cyPA and TCTP gene expressions were not varied compared to control groups after 28 days of exposure. Overall, the results indicated that HSP70 and CRT genes expression patterns might be potential early molecular biomarkers for predicting the harmful exposure level and ecotoxicological effects of polycyclic musks contaminated soil. PMID:23914539

  20. Earthworms as colonisers: primary colonisation of contaminated land, and sediment and soil waste deposits.

    PubMed

    Eijsackers, H

    2010-03-15

    This paper reviews the role of earthworms in the early colonisation of contaminated soils as well as sediment and waste deposits, which are worm-free because of anthropogenic activities such as open-cast mining, soil sterilisation, consistent pollution or remediation of contaminated soil. Earthworms live in close interaction with their soil environment and are able to change it considerably by their burrowing and litter comminuting behaviour. While earthworms have been studied extensively, several questions still remain unanswered such as: What are the characteristics of successful early colonisers? Do they function well in dispersal, individual establishment or population growth? Do the negative environmental conditions in these kinds of anthropogenic soils hamper colonization or are these colonizers relatively resistant to it? To what extent does colonization change the characteristics of the colonized substrate? In short, do earthworms impact the soil? In this paper, the characteristics that make earthworms successful colonisers are briefly described as well as which species are the most successful and under what circumstances, and what do earthworms contribute to the total process of succession. We propose that it is not so much eco-type or r-K strategy that govern success and succession of earthworm colonisation but rather environmental flexibility not only towards pH, desiccation, and temperature but also towards contaminants such as heavy metals. Moreover, the formation of an organic litter layer, in close connection with re-vegetation of the area, is essential for establishing earthworm populations, which, at first, are mainly superficially and shallow active species. The burrowing and organic matter digesting activity of these earthworms changes the upper soil to a well mixed humus layer suitable for deep burrowing earthworm species. PMID:20138645

  1. Impact of age of rubber (Hevea brasiliensis) plantation on earthworm communities of West Tripura (India).

    PubMed

    Chaudhuri, P S; Bhattacharjee, Subhalaxmi; Dey, Animesh; Chattopadhyay, Sharmila; Bhattacharya, Dipto

    2013-01-01

    A comparative analysis of earthworm communities was carried out in the rubber plantations (Hevea brasiliensis) of different age groups in West Tripura to understand the impact of such exotic and monoculture plantation in biodiversity conservation. Earthworm communities were studied on monthly basis over a period of one year (2006-2007) in the 3, 10, 14, 20 and 25 year-old plantations. Among twelve earthworm species collected from the studied sites, six species belonged to Octochaetidae [Eutyphoeus assomensis Stephenson, Eutyphoeus comillahnus Michaelsen, Lennogaster chittagongensis (Stephensen), Octochaetona beatrix Gates, Dichogaster offinis Michaelsen, Lennogaster yeicus (Stephensen)], two species each to Megascolecidae [Metaphire houlleti (Perrier), Konchurio sp. 1] and Moniligastridae [Drowida nepalensis Michaelsen, Drawida papillifer papillifer Stephenson], one species each to Glossoscolecidae [Pontoscolex corethrurus (Muller)] and Ocnerodrilidae [Gordiodrilus elegans Beddard]. Exotic species P corethrurus, M. houlleti and native peregrine species like D. nepolensis and D. papillifer papillifer were distributed in all the age groups of plantation, while other species showed restricted distribution. P. corethrurus contributed more than 60% biomass and 70% density of earthworm communities in rubber plantation. With aging of rubber plantations both the densities and biomasses of earthworms increased. High contents of polyphenol, flavonoid and lignin in the litters of 3 and 10 year-old-rubber plantations through their effects on food intake, probably resulted to low biomass values of earthworms in those age groups of plantation. With further increase in the age of plantations beyond 10 years, polyphenol, flavonoid and lignin contents decreased. Accordingly the biomass of earthworms increased with increase in the age of plantation. Soil moisture increased with increase in the age of plantation and there was a good positive correlation between soil moisture and earthworm biomass (p < 0.01). Density, biomass and dominance of earthworms increased while species diversity, species richness and species evenness of earthworm community were decreased with increase in the age of rubber plantation. PMID:24006808

  2. AVOIDING MANUSCRIPT MISTAKES

    PubMed Central

    Saliba, Susan A.

    2012-01-01

    Writing a scientific manuscript can be a consuming, but rewarding task with a number of intrinsic and extrinsic benefits. The ability to write a scientific manuscript is typically not an emphasized component of most entry?level professional programs. The purpose of this overview is to provide authors with suggestions to improve manuscript quality and to provide mechanisms to avoid common manuscript mistakes that are often identified by journal reviewers and editors. PMID:23091784

  3. 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.

  4. 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.

  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. 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…

  7. 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…

  8. Between-species jamming avoidance in Pipistrelles?

    PubMed

    Necknig, Veronika; Zahn, Andreas

    2011-05-01

    Past studies have reported that bats modify the spectral-temporal features of their vocalizations to avoid interference from the vocalizations of conspecifics (jamming avoidance). We tested for within, and between-species jamming avoidance in two sympatrically occurring species of vespertilionid bats, Pipistrellus pipistrellus and Pipistrellus nathusii. In both species the peak frequencies of the narrowband frequency component from samples of bats flying with conspecifics varied more than those from samples of bats flying alone, indicating intraspecific jamming avoidance. If individuals of the two species were recorded together, we found no reaction of P. nathusii. P. pipistrellus, however, used significantly higher frequencies than when recorded alone. As the narrowband frequency of this species normally overlaps with the frequency modulated (FM) part of P. nathusii calls, this can be interpreted as an interspecific jamming avoidance response. PMID:20938777

  9. 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

  10. 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.

  11. 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 bioturbation and material processing through earthworm intestines in determining the interactions between organic matter and mineral surface and thus helps understanding how soils' capacity to stabilize organic matter is influenced by invasive earthworm species.

  12. 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 changes in cast production should be considered for inclusion in current standard tests. PMID:20821048

  13. Human Hippocampus Arbitrates Approach-Avoidance Conflict

    PubMed Central

    Bach, Dominik R.; Guitart-Masip, Marc; Packard, Pau A.; Miró, Júlia; Falip, Mercè; Fuentemilla, Lluís; Dolan, Raymond J.

    2014-01-01

    Summary Animal models of human anxiety often invoke a conflict between approach and avoidance [1, 2]. In these, a key behavioral assay comprises passive avoidance of potential threat and inhibition, both thought to be controlled by ventral hippocampus [2–6]. Efforts to translate these approaches to clinical contexts [7, 8] are hampered by the fact that it is not known whether humans manifest analogous approach-avoidance dispositions and, if so, whether they share a homologous neurobiological substrate [9]. Here, we developed a paradigm to investigate the role of human hippocampus in arbitrating an approach-avoidance conflict under varying levels of potential threat. Across four experiments, subjects showed analogous behavior by adapting both passive avoidance behavior and behavioral inhibition to threat level. Using functional magnetic resonance imaging (fMRI), we observe that threat level engages the anterior hippocampus, the human homolog of rodent ventral hippocampus [10]. Testing patients with selective hippocampal lesions, we demonstrate a causal role for the hippocampus with patients showing reduced passive avoidance behavior and inhibition across all threat levels. Our data provide the first human assay for approach-avoidance conflict akin to that of animal anxiety models. The findings bridge rodent and human research on passive avoidance and behavioral inhibition and furnish a framework for addressing the neuronal underpinnings of human anxiety disorders, where our data indicate a major role for the hippocampus. PMID:24560572

  14. 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.

  15. 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.

  16. Interactions of earthworms with indigenous and bioaugmented PCB-degrading bacteria.

    PubMed

    Luepromchai, Ekawan; Singer, Andrew C; Yang, Ching-Hong; Crowley, David E

    2002-09-01

    Partial bioremediation of polychlorinated biphenyl (PCB)-contaminated soils has been achieved using bioaugmentation with PCB-degrading bacteria and earthworms. To further study the contribution of earthworms to bioremediation, an experiment was conducted in which the changes in indigenous and bioaugmented PCB-degrading bacteria were analyzed during treatment of contaminated soil using earthworms (Pheretima hawayana) alone or in combination with the PCB-degrading bacteria, Ralstonia eutrophus and Rhodococcus sp. ACS. Bacteria used for bioaugmentation were induced with carvone and salicylic acid in culture and were repeatedly applied every 3-4 days to the surface of unmixed, 20-cm long soil columns containing 100 ppm Aroclor 1242. After 9 weeks of treatment, the soil bacterial communities were analyzed using PCR primers for the bph genes. Results showed that approximately 50% of the PCBs were removed in the top 9 cm using a combination of earthworms and bioaugmentation, whereas bioaugmentation or earthworms applied alone were effective only for removing PCBs from the top 3 cm of the soil columns. Enhanced removal of PCBs caused by earthworms was associated with an increase in the population size of culturable, indigenous biphenyl-degrading bacteria, and an increase in the level of the bphA and bphC genes. The results suggest that earthworms facilitate PCB bioremediation by enhancing the dispersal of PCB-degrading bacteria in bioaugmented columns, as well as providing environmental conditions that favor the growth and activity of indigenous PCB-degrading bacteria. PMID:19709253

  17. 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.

  18. 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.

  19. 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.

  20. 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

  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. 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.

  3. 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

  4. 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 chemistry and 210Pb activities, together with ongoing monitoring of earthworms’ species composition and population density, will allow us to understand how and to what degree the soil mixing organisms affect chemical denudation of landscapes, which is central to our efforts in finding the topographic signatures of life.

  5. Importance of earthworm-seed interactions for the composition and structure of plant communities: A review

    NASA Astrophysics Data System (ADS)

    Forey, Estelle; Barot, Sébastien; Decaëns, Thibaud; Langlois, Estelle; Laossi, Kam-Rigne; Margerie, Pierre; Scheu, Stefan; Eisenhauer, Nico

    2011-11-01

    Soil seed bank composition and dynamics are crucial elements for the understanding of plant population and community ecology. Earthworms are increasingly recognized as important dispersers and predators of seeds. Through direct and indirect effects they influence either positively or negatively the establishment and survival of seeds and seedlings. Seedling establishment is affected by a variety of earthworm-mediated mechanisms, such as selective seed ingestion and digestion, acceleration or deceleration of germination, and seed transport. Earthworm casts deposited on the soil surface and the entrance of earthworm burrows often contain viable seeds and constitute important regeneration niches for plant seedlings and therefore likely favour specific seed traits. However, the role of earthworms as seed dispersers, mediators of seed bank dynamics and seed predators has not been considered in concert. The overall effect of earthworms on plant communities remains little understood. Most knowledge is based on laboratory studies on temperate species and future work has to explore the biological significance of earthworm-seed interactions under more natural conditions. In this review we summarize the current knowledge on earthworm-seed interactions and discuss factors determining these interactions. We highlight that this interaction may be an underappreciated, yet major driving force for the dynamics of soil seed banks and plant communities which most likely have experienced co-evolutionary processes. Despite the experimental bias, we hypothesize that the knowledge gathered in the present review is of crucial relevance for restoration and conservation ecology. For instance, as earthworms emerge as successful and ubiquitous invaders in various ecosystems, the summarized information might serve as a basis for realistic estimations and modelling of consequences on native plant communities. We depict promising directions of future research and point to the need to consider above- and belowground interactions in order to mechanistically understand the driving forces of plant community assembly.

  6. 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 surface area (presumably due to the crystalline iron oxides) in the heavily invaded soils. Water chemistry of lysimeter samples show a similar trend: the heavily invaded soils show a lower solute concentration of Ca but higher concentrations of Fe. These data indicate that exotic earthworms, while significantly affecting chemical weathering processes in the soils, are seriously altering (1) the budgets of inorganic nutrient in these hardwood forests and (2) the minerals' potential capacity to complex carbon on their surface area. Our ongoing work includes the use of optically stimulated luminescence (OSL) dating which may complement the 137-Cs and 210-Pb data in constraining soil mixing. Additionally, we will incorporate leaf litter chemistry and continue water and earthworm sampling to understand the degree that exotic earthworms contribute to chemical weathering in the Great Lakes hardwood ecosystems.

  7. 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.

  8. 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.

  9. Joint toxicity of chlorpyrifos, atrazine, and cadmium at lethal concentrations to the earthworm Eisenia fetida.

    PubMed

    Yang, Guiling; Chen, Chen; Wang, Yanhua; Cai, Leiming; Kong, Xiangzhen; Qian, Yongzhong; Wang, Qiang

    2015-06-01

    Contaminants in the environment often occur as complex mixtures, and their combined effect may exhibit toxicity to organisms. Risk assessments based on individual components tend to underestimate the effects associated with toxic action of mixtures. Toxicity studies on chemical mixtures are urgently required to assess their potential combined toxicities. The combination index (CI)-isobologram method was used to study chemical interactions to determine the nature of toxicological interactions of two pesticides chlorpyrifos and atrazine and a heavy metal cadmium toward earthworm Eisenia fetida by artificial soil and filter paper acute toxicity tests. The results showed that the binary mixture of chlorpyrifos and atrazine was antagonistic toward E. fetida at all f a levels in an artificial soil test. The combination of atrazine and Cd exhibited a slight degree of synergism throughout the exposure range, while chlorpyrifos plus Cd combination led to dual antagonistic/synergistic behavior. The nature of binary combinations in filter paper displayed opposite interaction to that in the artificial soil test, and the toxicity of ternary mixtures was not significantly synergistic than their binaries. The combination index (CI)-isobologram equation method could determine the interaction types for a series of effect levels of three chemicals in binary and ternary combinations in two types of acute earthworm tests. However, the nature of these interactions was not uniform along the f a level range in any of the two tests. Bioavailability, the nature of toxicological interaction, and the test organism need to be considered for understanding exposures and chemical measures. The synergistic effect for the particular binary combination suggests that a potential risk associated with the co-occurrence of these pollutants may still exist, which may have implications in risk assessment for the terrestrial environment. The combined effects between different contaminants might be influenced by the category of chemical, as well as the bioassay procedures. More studies of combined toxicities among these contaminants in the terrestrial environment should be conducted to identify the mixtures exhibiting synergistic pattern of interactions. PMID:25595933

  10. 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

  11. 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…

  12. Endocrine disrupting chemicals accumulate in earthworms exposed to sewage effluent.

    PubMed

    Markman, Shai; Guschina, Irina A; Barnsley, Sara; Buchanan, Katherine L; Pascoe, David; Müller, Carsten T

    2007-11-01

    Endocrine disrupting chemicals (EDCs) can alter endocrine function in exposed animals. Such critical effects, combined with the ubiquity of EDCs in sewage effluent and potentially in tapwater, have led to concerns that they could be major physiological disruptors for wildlife and more controversially for humans. Although sewage effluent is known to be a rich source of EDCs, there is as yet no evidence for EDC uptake by invertebrates that live within the sewage treatment system. Here, we describe the use of an extraction method and GC-MS for the first time to determine levels of EDCs (e.g., dibutylphthalate, dioctylphthalate, bisphenol-A and 17beta-estradiol) in tissue samples from earthworms (Eisenia fetida) living in sewage percolating filter beds and garden soil. To the best of our knowledge, this is the first such use of these techniques to determine EDCs in tissue samples in any organism. We found significantly higher concentrations of these chemicals in the animals from sewage percolating filter beds. Our data suggest that earthworms can be used as bioindicators for EDCs in these substrates and that the animals accumulate these compounds to levels well above those reported for waste water. The potential transfer into the terrestrial food chain and effects on wildlife are discussed. PMID:17675209

  13. 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

  14. 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.

  15. Biomanagement of petrochemical sludge using an exotic earthworm Eudrilus eugineae.

    PubMed

    Banu, J Rajesh; Esakkiraj, S; Nagendran, R; Logakanthi, S

    2005-01-01

    Petrochemical industry have severe problem in disposing effluent and semisolid sludge despite repeated recycling. It requires further treatment prior to disposal of sludge. In recent years biological treatment methods received much attention and considered as an efficient low-cost treatment. One such method is vermiculture treatment The end product of vermicompost is rich in essential micro and macronutrients along with microorganisms in a very simple form. Adding cast, not only improves the soil structure and fertility but also leads to improvement in overall plant growth and thus increase their yield. The present study was carried out to dispose the petrochemical sludge biologically using an exotic earthworm Eudrilus eugineae. The petrochemical sludge at various concentrations 25, 50 and 75% were subjected to vermicomposting treatment for a period of 60 days. During the period of study, data were collected on life form of earthworm and chemical analysis of the sludge before and after treatment. The microbial analysis was carried out fortnightly. The results indicate that 25 and 50% concentration of sludge was ideal for the vermicomposting, whereas the higher concentration inhibits the vermicomposting. PMID:16114460

  16. 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.

  17. 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.

  18. 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 ?-? 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.

  19. [Nitrogen removal in earthworm ecofilter treating domestic wastewater].

    PubMed

    Fang, Cai-xia; Luo, Xing-zhang; Guo, Fei-hong; Zheng, Zheng; Li, Zhe-qin

    2010-02-01

    The removal efficiency of different forms of nitrogen was studied in earthworm ecofilter treating domestic wastewater, and the mechanisms were discussed. Results indicated that, the major form of total nitrogen (TN) in influent water and effluent water were existed as ammonia-nitrogen (NH4+ -N) and nitrate-nitrogen (NO3- -N), respectively. NH4+ -N /TN in influent water and NO3- -N /TN in effluent water were 83.88% and 76.46%, respectively, NH4+ -N decreased and NO3- -N increased during the process. The average removal efficiency of TN and NH4+ -N were 28.08% and 90.44%, respectively, nitrate-nitrogen accumulated massively and nitrite-nitrogen (NO2- -N) accumulated a little. It was also observed that nitrification in earthworm ecofilter was strong and the denitrification was inhibited, TN removal was not as obvious as the NH4+ -N removal due to the poor denitrification environment. The overall removal of TN can be improved by increasing wet/dry ratio, modifying the structure of filter, multistage filter series, following by constructed wetland, and increasing C/N ratio of the influent water. PMID:20391701

  20. 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

  1. 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

  2. Avoiding Infection After Ear Piercing

    MedlinePLUS

    ... Text Size Email Print Share Avoiding Infection After Ear Piercing Page Content Article Body What is the best way to avoid infection after ear piercing? Ears may be pierced for cosmetic reasons ...

  3. Avoidance Strategies in Intimate Relationships.

    ERIC Educational Resources Information Center

    Belk, Sharyn S.; And Others

    Avoidance strategies involve the tactics and techniques people use when they don't wish to be influenced by others. To investigate the types of avoidance strategies men and women use to deal with an unwelcome persuasion attempt from an intimate partner, undergraduates wrote essays describing how they avoided such attempts. A 24-strategy coding…

  4. Redundant Robot Can Avoid Obstacles

    NASA Technical Reports Server (NTRS)

    Homayoun, Seraji; Colbaugh, Richard; Glass, Kristin

    1991-01-01

    Simple and direct control scheme enables redundant robot to avoid obstacles in workspace. In proposed scheme, called "configuration control", degrees of freedom used to configure robot to satisfy set of inequality constraints representing avoidance of obstacles, while simultaneously making end effector follow desired trajectory. Provides capability to avoid obstacles in dynamically varying environment where apriori planning of tasks not feasible.

  5. 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.

  6. Toxicity of coelomic fluid of the earthworm Eisenia foetida to vertebrates but not invertebrates: probable role of sphingomyelin.

    PubMed

    Kobayashi, H; Ohtomi, M; Sekizawa, Y; Ohta, N

    2001-03-01

    The coelomic fluid (CF) of the earthworm Eisenia foetida exhibits a wide variety of biological activities. We found that the CF was not toxic to 42 species, belonging to seven invertebrate phyla, almost all in aquatic adults and larvae exposed to CF. Eleven teleostean species tested died in 0.2-1% CF mostly between 10 and 120 min and the effects were dose-dependent. Tadpoles of the toad Bufo japonicus formosus died in 0.4-2% CF between 80 and 225 min depending upon size, with larger tadpoles surviving longer. Before dying, all experimental tadpoles developed curled and shrunken tails. The Okinawa tree lizard, soft-shelled turtle, Japanese quail, mouse and rat all died after i.v. injection of CF (above 20 microl/kg). Thus, CF was not toxic to invertebrates, but toxic to vertebrates. After heating, CF lost its toxicity to fish, tadpoles and mice. Both CF and lysenin incubated with sphingomyelin-liposomes (SM-liposomes) were no longer toxic, suggesting the involvement of SM in the toxicity. Lysenin, which is a constituent of CF and known to bind specifically to sphingomyelin, exhibited toxicity similar to that of CF. Thus, lysenin in CF is probably responsible for the toxic effects of CF by binding to SM in vertebrate tissues. The bodies of invertebrates might contain little or no SM, while those of vertebrates do contain SM. The coelomic fluid of the earthworm Pheretima communissima has no toxicity to mouse. PMID:11255113

  7. 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}.

  8. 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.

  9. Syntheses of glycoclusters containing a phosphocholine residue related to a glycosphingolipid from the earthworm Pheretima hilgendorfi.

    PubMed

    Hada, Noriyasu; Shida, Yukihiko; Negishi, Natsuko; Schweizer, Frank; Takeda, Tadahiro

    2009-10-01

    Three types of glycoclusters related to an amphoteric glycosphingolipid found in the earthworm Pheretima hilgendorfi were synthesized. The glycoclusters were prepared from a common precursor and a simple approach for the rational design of a glycocluster was developed. PMID:19801862

  10. Effect of lead on survival, locomotion and sperm morphology of Asian earthworm, Pheretima guillelmi.

    PubMed

    Zheng, Rongquan; Li, Canyang

    2009-01-01

    To provide basic toxicity data for formulating risk characterization benchmarks, the effects of lead on survival, locomotion, and sperm morphology were investigated in the Asian earthworm Pheretima guillelmi. The LC50 of P. guillelmi for 7 and 14 d were 4285 +/- 339 mg/kg and 3207 +/- 248 mg/kg, which shows P. guillelmi can tolerate a higher concentration of lead nitrate. The average weight of the surviving earthworms decreased at concentration of 2800 mg Pb/kg soil, and the locomotor ability of earthworms exposed to a range of soil Pb concentrations showed a general decrease with increasing Pb concentrations. We also presented data depicting the sperm morphology of earthworms, which shows potential as a sensitive biomarker for measuring the effects of heavy metal on reproduction. PMID:20108673

  11. 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.

  12. 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

  13. 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

  14. Glyphosate herbicide affects belowground interactions between earthworms and symbiotic mycorrhizal fungi in a model ecosystem.

    PubMed

    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

  15. Inhibition effect of glyphosate on the acute and subacute toxicity of cadmium to earthworm Eisenia fetida.

    PubMed

    Zhou, Chui-Fan; Wang, Yu-Jun; Sun, Rui-Juan; Liu, Cun; Fan, Guang-Ping; Qin, Wen-Xiu; Li, Cheng-Cheng; Zhou, Dong-Mei

    2014-10-01

    The acute and subacute toxicities of cadmium (Cd) to earthworm Eisenia fetida in the presence and absence of glyphosate were studied. Although Cd is highly toxic to E. fetida, the presence of glyphosate markedly reduced the acute toxicity of Cd to earthworm; both the mortality rate of the earthworms and the accumulation of Cd decreased with the increase of the glyphosate/Cd molar ratio. The subcellular distribution of Cd in E. fetida tissues showed that internal Cd was dominant in the intact cells fraction and the heat-stable proteins fraction. The presence of glyphosate reduced the concentration of Cd in all fractions, especially the intact cells. During a longer period of exposure, the weight loss of earthworm and the total Cd absorption was alleviated by glyphosate. Thus, the herbicide glyphosate can reduce the toxicity and bioavailability of Cd in the soil ecosystems at both short- and long-term exposures. PMID:25043609

  16. 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 ...

  17. 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...

  18. 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.

  19. 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...

  20. 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.

  1. Effects of earthworms on physicochemical properties and microbial profiles during vermicomposting of fresh fruit and vegetable wastes.

    PubMed

    Huang, Kui; Li, Fusheng; Wei, Yongfen; Fu, Xiaoyong; Chen, Xuemin

    2014-10-01

    This study aimed to investigate the effect of earthworms on physicochemical and microbial properties during vermicomposting of fresh fruit and vegetable wastes (FVW) by contrasting two decomposing systems of FVW with and without earthworms for 5weeks. Compared to control treatment (without earthworms), vermicomposting treatment resulted in a rapid decrease of electrical conductivity and losses of total carbon and nitrogen from the 2nd week. Quantitative PCR displayed that earthworms markedly enhanced bacterial and fungal densities, showing the higher values than control, during the whole decomposition process. In addition, denaturing gradient gel electrophoresis combined with sequencing analysis revealed that earthworms pronouncedly modified bacterial and fungal community structures, through broadening the community diversities of Actinobacteria, Bacteroidetes, Proteobacteria, and Ascomycotina. These results suggest that the presence of earthworms promoted the activity and population of bacteria and fungi, and modified their communities, thus altering the decomposition pathway of fresh FVW. PMID:25118152

  2. 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)…

  3. 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)…

  4. 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.

  5. 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

  6. 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

  7. 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.

  8. Soil geochemistry and digestive solubilization control mercury bioaccumulation in the earthworm Pheretima guillemi.

    PubMed

    Dang, Fei; Zhao, Jie; Greenfield, Ben K; Zhong, Huan; Wang, Yujun; Yang, Zhousheng; Zhou, Dongmei

    2015-07-15

    Mercury presents a potential risk to soil organisms, yet our understanding of mercury bioaccumulation in soil dwelling organisms is limited. The influence of soil geochemistry and digestive processes on both methylmercury (MeHg) and total mercury (THg) bioavailability to earthworms (Pheretima guillemi) was evaluated in this study. Earthworms were exposed to six mercury-contaminated soils with geochemically contrasting properties for 36 days, and digestive fluid was concurrently collected to solubilize soil-associated mercury. Bioaccumulation factors were 7.5-31.0 and 0.2-0.6 for MeHg and THg, respectively, and MeHg accounted for 17-58% of THg in earthworm. THg and MeHg measured in soils and earthworms were negatively associated with soil total organic carbon (TOC). Earthworm THg and MeHg also increased with increasing soil pH. The proportion of MeHg and THg released into the digestive fluid (digestive solubilizable mercury, DSM) was 8.3-18.1% and 0.4-1.3%, respectively. The greater solubilization of MeHg by digestive fluid than CaCl2, together with a biokinetic model-based estimate of dietary MeHg uptake, indicated the importance of soil ingestion for MeHg bioaccumulation in earthworms. PMID:25781374

  9. 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.

  10. 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

  11. Isolation and characterization of aerobic microorganisms with cellulolytic activity in the gut of endogeic earthworms.

    PubMed

    Fujii, Katsuhiko; Ikeda, Kana; Yoshida, Seo

    2012-09-01

    The ability of earthworms to decompose lignocellulose involves the assistance of microorganisms in their digestive system. While many studies have revealed a diverse microbiota in the earthworm gut, including aerobic and anaerobic microorganisms, it remains unclear which of these species contribute to lignocellulose digestion. In this study, aerobic microorganisms with cellulolytic activity isolated from the gut of two endogeic earthworms, Amynthas heteropoda (Megascolecidae) and Eisenia fetida (Lumbricidae) were isolated by solid culture of gut homogenates using filter paper as a carbon source. A total of 48 strains, including four bacterial and four fungal genera, were isolated from two earthworm species. Characterization of these strains using enzyme assays showed that the most representative ones had exocellulase and xylanase activities, while some had weak laccase activity. These findings suggest that earthworms digest lignocellulose by exploiting microbial exocellulase and xylanase besides their own endocellulase. Phylogenetic analysis showed that among the cellulolytic isolates in both earthworm species Burkholderia and Chaetomium were the dominant bacterial and fungal members. PMID:23847816

  12. Self-assemblage and quorum in the earthworm Eisenia fetida (Oligochaete, Lumbricidae).

    PubMed

    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

  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. 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.

  15. 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.

  16. 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

  17. 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

  18. 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

  19. 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

  20. 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

  1. Effects of biochar and the geophagous earthworm Metaphire guillelmi on fate of (14)C-catechol in an agricultural soil.

    PubMed

    Shan, Jun; Wang, Yongfeng; Gu, Jianqiang; Zhou, Wenqiang; Ji, Rong; Yan, Xiaoyuan

    2014-07-01

    Both biochar and earthworms can exert influence on behaviors of soil-borne monomeric phenols in soil; however, little was known about the combined effects of biochar and earthworm activities on fate of these chemicals in soil. Using (14)C-catechol as a representative, the mineralization, transformation and residue distribution of phenolic humus monomer in soil amended with different amounts of biochar (0%, 0.05%, 0.5%, and 5%) without/with the geophagous earthworm Metaphire guillelmi were investigated. The results showed biochar at amendment rate <0.5% did not affect (14)C-catechol mineralization, whereas 5% biochar amendment significantly inhibited the mineralization. Earthworms did not affect the mineralization of (14)C-catechol in soil amended with <0.5% biochar, but significantly enhanced the mineralization in 5% biochar amended soil when they were present in soil for 9 d. When earthworms were removed from the soil, the mineralization of (14)C-catechol was significantly lower than that of in earthworm-free soil indicating that (14)C-catecholic residues were stabilized during their passage through earthworm gut. The assimilation of (14)C by earthworms was low (1.2%), and was significantly enhanced by biochar amendment, which was attributed to the release of biochar-associated (14)C-catecholic residues during gut passage of earthworm. PMID:24875877

  2. A novel gut tetradecapeptide isolated from the earthworm, Eisenia foetida.

    PubMed

    Ukena, K; Oumi, T; Matsushima, O; Ikeda, T; Fujita, T; Minakata, H; Nomoto, K

    1995-01-01

    A novel bioactive tetradecapeptide, GFKDGAADRISHGFamide, was isolated from the gut of the oligochaete annelid, Eisenia foetida, using the isolated anterior gut (crop-gizzard) as a bioassay system. A highly homologous peptide, GFRDGSADRISHGFamide, was also purified from the whole body of another species of earthworm, Pheretima vittata. These peptides were termed Eisenia tetradecapeptide (ETP) and Pheretima tetradecapeptide (PTP), respectively. Both the peptides showed a potent excitatory action on spontaneous contractions of the anterior gut with a threshold as low as 10(-10)-10(-9) M. These peptides were significantly homologous to molluscan tetradecapeptides and, to a lesser extent, to arthropodan tridecapeptides that have been reported to date. All these peptides seem to be evolutionally related to each other. PMID:8532604

  3. 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

  4. 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 human health.

  5. Inferred threat and safety: symbolic generalization of human avoidance learning.

    PubMed

    Dymond, Simon; Schlund, Michael W; Roche, Bryan; Whelan, Robert; Richards, Jennifer; Davies, Cara

    2011-10-01

    Symbolic generalization of avoidance may underlie the aetiology and maintenance of anxiety disorders. The aim of the present study was to demonstrate inferred threat-avoidance and safety (non-avoidance) behaviours that occur in the presence of stimuli indirectly related to learned threat and safety cues. A laboratory experiment was conducted involving two symbolic stimulus equivalence relations consisting of three physically dissimilar stimuli (avoidance cues: AV1-AV2-AV3 and neutral cues: N1-N2-N3). During avoidance learning involving aversive images and sounds, a key-press avoidance response was trained for one member of one of the relations (AV2) and non-avoidance for another (N2). Inferred threat and safety behaviour and ratings of the likelihood of aversive events were tested with presentations of all remaining stimuli. Findings showed a significantly high percentage of avoidance to both the learned and inferred threat cues and less avoidance to both the learned and inferred safety cues. Ratings in the absence of avoidance were high during training and testing to threat cues and low to safety cues and were generally lower in the presence of avoidance. Implications for associative and behavioural accounts of avoidance, and modern therapies for anxiety disorders are discussed. PMID:21767825

  6. 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 that higher 137Cs activity was located from 8-16 cm depth and no 137Cs activity was measured below 20 cm. In contrast, in the e[CO2] treatment, peak 137Cs activity was slightly deeper (10-18 cm), and 137Cs activity was still measured below 22 cm. Mean earthworm density was higher in e[CO2] than c[CO2] treatments (168 m-2 and 87 m-2, respectively; p = 0.046); earthworm fresh weights, however, did not differ significantly between treatments (32 g m-2 and 18 g m-2, respectively; p = 0.182). The 137Cs vertical distribution suggest that soil mixing occurs deeper in e[CO2] than in c[CO2] treatments, which is consistent with higher earthworm densities in e[CO2] than in c[CO2] treatments. Mixing deeper low carbon content soil with shallower high carbon soil may result in a dilution of net carbon inputs in forest soils exposed to e[CO2]. Vertical dilution of new carbon may explain why carbon accrual is detected only near the surface at this FACE site. By identifying the depths of active soil mixing and possible soil mixing mechanisms (e.g. earthworms), accounting of new organic carbon accrual could be more reliably determined for forest soils in response to e[CO2] conditions.

  7. Healthcare avoidance: a critical review.

    PubMed

    Byrne, Sharon K

    2008-01-01

    The purpose of this study is to provide a critical review and synthesis of theoretical and research literature documenting the impact of avoidance on healthcare behaviors, identify the factors that influence healthcare avoidance and delay in the adult population, and propose a direction for future research. The Theory of Reasoned Action, Theory of Planned Behavior, Theory of Care-Seeking Behavior, the Transtheoretical Model, and the Behavioral Model of Health Services Use/Utilization are utilized to elaborate on the context within which individual intention to engage in healthcare behaviors occurs. Research literature on the concept of healthcare avoidance obtained by using computerized searches of CINAHL, MEDLINE, PSYCH INFO, and HAPI databases, from 1995 to 2007, were reviewed. Studies were organized by professional disciplines. Healthcare avoidance is a common and highly variable experience. Multiple administrative, demographic, personal, and provider factors are related to healthcare avoidance, for example, distrust of providers and/or the science community, health beliefs, insurance status, or socioeconomic/income level. Although the concept is recognized by multiple disciplines, limited research studies address its impact on healthcare decision making. More systematic research is needed to determine correlates of healthcare avoidance. Such studies will help investigators identify patients at risk for avoidant behaviors and provide the basis for health-promoting interventions. Methodological challenges include identification of characteristics of individuals and environments that hinder healthcare behaviors, as well as, the complexity of measuring healthcare avoidance. Studies need to systematically explore the influence of avoidance behaviors on specific healthcare populations at risk. PMID:18758277

  8. Modelling spatiotemporal distribution patterns of earthworms in order to indicate hydrological soil processes

    NASA Astrophysics Data System (ADS)

    Palm, Juliane; Klaus, Julian; van Schaik, Loes; Zehe, Erwin; Schröder, Boris

    2010-05-01

    Soils provide central ecosystem functions in recycling nutrients, detoxifying harmful chemicals as well as regulating microclimate and local hydrological processes. The internal regulation of these functions and therefore the development of healthy and fertile soils mainly depend on the functional diversity of plants and animals. Soil organisms drive essential processes such as litter decomposition, nutrient cycling, water dynamics, and soil structure formation. Disturbances by different soil management practices (e.g., soil tillage, fertilization, pesticide application) affect the distribution and abundance of soil organisms and hence influence regulating processes. The strong relationship between environmental conditions and soil organisms gives us the opportunity to link spatiotemporal distribution patterns of indicator species with the potential provision of essential soil processes on different scales. Earthworms are key organisms for soil function and affect, among other things, water dynamics and solute transport in soils. Through their burrowing activity, earthworms increase the number of macropores by building semi-permanent burrow systems. In the unsaturated zone, earthworm burrows act as preferential flow pathways and affect water infiltration, surface-, subsurface- and matrix flow as well as the transport of water and solutes into deeper soil layers. Thereby different ecological earthworm types have different importance. Deep burrowing anecic earthworm species (e.g., Lumbricus terrestris) affect the vertical flow and thus increase the risk of potential contamination of ground water with agrochemicals. In contrast, horizontal burrowing endogeic (e.g., Aporrectodea caliginosa) and epigeic species (e.g., Lumbricus rubellus) increase water conductivity and the diffuse distribution of water and solutes in the upper soil layers. The question which processes are more relevant is pivotal for soil management and risk assessment. Thus, finding relevant environmental predictors which explain the distribution and dynamics of different ecological earthworm types can help us to understand where or when these processes are relevant in the landscape. Therefore, we develop species distribution models which are a useful tool to predict spatiotemporal distributions of earthworm occurrence and abundance under changing environmental conditions. On field scale, geostatistical distribution maps have shown that the spatial distribution of earthworms depends on soil parameters such as food supply, soil moisture, bulk density but with different patterns for earthworm stages (adult, juvenile) and ecological types (anecic, endogeic, epigeic). On landscape scales, earthworm distribution seems to be strongly controlled by management/disturbance-related factors. Our study shows different modelling approaches for predicting distribution patterns of earthworms in the Weiherbach area, an agricultural site in Kraichtal (Baden-Württemberg, Germany). We carried out field studies on arable fields differing in soil management practices (conventional, conservational), soil properties (organic matter content, texture, soil moisture), and topography (slope, elevation) in order to identify predictors for earthworm occurrence, abundance and biomass. Our earthworm distribution models consider all ecological groups as well as different life stages, accounting for the fact that the activity of juveniles is sometimes different from those of adults. Within our BIOPORE-project it is our final goal to couple our distribution models with population dynamic models and a preferential flow model to an integrated ecohydrological model to analyse feedbacks between earthworm engineering and transport characteristics affecting the functioning of (agro-) ecosystems.

  9. Toxicity testing of trinitrotoluene-contaminated soil composts

    SciTech Connect

    Honeycutt, M.E.; McFarland, V.A.; Jarvis, A.S.

    1997-10-01

    The Mutatox{trademark} assay and earthworm acute toxicity test were employed to evaluate the efficacy of composting in reducing the toxicity of TNT-contaminated soils. The Mutatox assay is a proprietary bacterial bioluminescence test that determines the mutagenic potential of sample extracts. The earthworm acute toxicity test was chosen because it exposes the organisms to the unaltered contaminant/solid matrix. Rockeye soil, a TNT-contaminated soil collected from a military installation, was composted using two methods. This yielded five samples, Rockeye, Compost A composting. Soil extracts were prepared for Mutatox using the sonification method. Ten serial dilution samples were tested soils/artificial soil were tested in the earthworm toxicity test. In the Rockeye soil samples, a toxic response was shown in both test methods. Mutatox indicated no toxicity in Composts A and B after composting but did not show a positive mutagenic response in the lower serial dilutions. The LC50s for Compost A and B after composting in the earthworm toxicity test were 35.3% and 100%, respectively. Using Mutatox and the earthworm toxicity test together provides a sensitive means of monitoring the effectiveness of various composting techniques for remediating TNT-contaminated soils.

  10. Chemical avoidance responses of fishes.

    PubMed

    Tierney, Keith B

    2016-05-01

    The hydrosphere is a repository for all of our waste and mistakes, be they sewage, garbage, process-affected waters, runoff, and gases. For fish living in environments receiving undesirable inputs, moving away seems an obvious way to avoid harm. While this should occur, there are numerous examples where it will not. The inability to avoid harmful environments may lead to sensory impairments that in turn limit the ability to avoid other dangers or locate benefits. For avoidance to occur, the danger must first be perceived, which may not happen if the fish is 'blinded' in some capacity. Second, the danger must be recognized for what it is, which may also not happen if the fish is cognitively confused or impaired. Third, it is possible that the fish may not be able to leave the area, or worse, learns to prefer a toxic environment. Concerning generating regulations around avoidance, there are two possibilities: that an avoidance threshold be used to set guidelines for effluent release with the intention of driving fishes away; the second is to set a contaminant concentration that would not affect the avoidance or attraction responses to other cues. With the complexities of the modern world in which we release diverse pollutants, from light to municipal effluents full of 1000s of chemicals, to the diversity present in ecosystems, it is impossible to have avoidance data on every stimulus-species combination. Nevertheless, we may be able to use existing avoidance response data to predict the likelihood of avoidance of untested stimuli. Where we cannot, this review includes a framework that can be used to direct new research. This review is intended to collate existing avoidance response data, provide a framework for making decisions in the absence of data, and suggest studies that would facilitate the prediction of risk to fish health in environments receiving intentional and unintentional human-based chemical inputs. PMID:26970365

  11. JPL Counterfeit Parts Avoidance

    NASA Technical Reports Server (NTRS)

    Risse, Lori

    2012-01-01

    SPACE ARCHITECTURE / ENGINEERING: It brings an extreme test bed for both technologies/concepts as well as procedures/processes. Design and construction (engineering) always go together, especially with complex systems. Requirements (objectives) are crucial. More important than the answers are the questions/Requirements/Tools-Techniques/Processes. Different environments force architects and engineering to think out of the box. For instance there might not be gravity forces. Architectural complex problems have common roots: in Space and on Earth. Let us bring Space down on Earth so we can keep sending Mankind to the stars from a better world. Have fun being architects and engineers...!!! This time is amazing and historical. We are changing the way we inhabit the solar systems!

  12. Evolution of the tripartite symbiosis between earthworms, Verminephrobacter and Flexibacter-like bacteria

    PubMed Central

    Møller, Peter; Lund, Marie B.; Schramm, Andreas

    2015-01-01

    Nephridial (excretory organ) symbionts are widespread in lumbricid earthworms and the complexity of the nephridial symbiont communities varies greatly between earthworm species. The two most common symbionts are the well-described Verminephrobacter and less well-known Flexibacter-like bacteria. Verminephrobacter are present in almost all lumbricid earthworms, they are species-specific, vertically transmitted, and have presumably been associated with their hosts since the origin of lumbricids. Flexibacter-like symbionts have been reported from about half the investigated earthworms; they are also vertically transmitted. To investigate the evolution of this tri-partite symbiosis, phylogenies for 18 lumbricid earthworm species were constructed based on two mitochondrial genes, NADH dehydrogenase subunit 2 (ND2) and cytochrome c oxidase subunit I (COI), and compared to their symbiont phylogenies based on RNA polymerase subunit B (rpoB) and 16S rRNA genes. The two nephridial symbionts showed markedly different evolutionary histories with their hosts. For Verminephrobacter, clear signs of long-term host-symbiont co-evolution with rare host switching events confirmed its ancient association with lumbricid earthworms, likely dating back to their last common ancestor about 100 million years (MY) ago. In contrast, phylogenies for the Flexibacter-like symbionts suggested an ability to switch to new hosts, to which they adapted and subsequently became species-specific. Putative co-speciation events were only observed with closely related host species; on that basis, this secondary symbiosis was estimated to be minimum 45 MY old. Based on the monophyletic clustering of the Flexibacter-like symbionts, the low 16S rRNA gene sequence similarity to the nearest described species (<92%) and environmental sequences (<94.2%), and the specific habitat in the earthworm nephridia, we propose a new candidate genus for this group, Candidatus Nephrothrix. PMID:26074907

  13. Declines in woodland salamander abundance associated with non-native earthworm and plant invasions.

    PubMed

    Maerz, John C; Nuzzo, Victoria A; Blossey, Bernd

    2009-08-01

    Factors that negatively affect the quality of wildlife habitat are a major concern for conservation. Non-native species invasions, in particular, are perceived as a global threat to the quality of wildlife habitat. Recent evidence indicates that some changes to understory plant communities in northern temperate forests of North America, including invasions by 3 non-native plant species, are facilitated by non-native earthworm invasion. Furthermore, non-native earthworm invasions cause a reduction in leaf litter on the forest floor, and the loss of forest leaf litter is commonly associated with declines in forest fauna, including amphibians. We conducted a mark-recapture study of woodland salamander abundance across plant invasion fronts at 10 sites to determine whether earthworm or plant invasions were associated with reduced salamander abundance. Salamander abundance declined exponentially with decreasing leaf litter volume. There was no significant relationship between invasive plant cover and salamander abundance, independent of the effects of leaf litter loss due to earthworm invasion. An analysis of selected salamander prey abundance (excluding earthworms) at 4 sites showed that prey abundance declined with declining leaf litter. The loss of leaf litter layers due to non-native earthworm invasions appears to be negatively affecting woodland salamander abundance, in part, because of declines in the abundance of small arthropods that are a stable resource for salamanders. Our results demonstrate that earthworm invasions pose a significant threat to woodland amphibian fauna in the northeastern United States, and that plant invasions are symptomatic of degraded amphibian habitat but are not necessarily drivers of habitat degradation. PMID:19236449

  14. Enhancement of chlorophenol sorption on soil by geophagous earthworms (Metaphire guillelmi).

    PubMed

    Shan, Jun; Xu, Jun; Zhou, Wenqiang; Ji, Liangliang; Cui, Yibin; Guo, Hongyan; Ji, Rong

    2011-01-01

    Earthworms are the dominant soil biomass of many terrestrial ecosystems and markedly influence the physico-chemical and biological properties of soil; however, little is known about the effects of earthworm activities on the environmental behavior of micropollutants in soil. We studied the sorption and desorption of 2,4-dichlorophenol, 2,4,6-trichlorophenol, and pentachlorophenol on geophagous earthworm (anecic Metaphire guillelmi) casts of various aging times and on the parent soil. The casts were characteristic of lower pH and higher content of fine particles (silt and clay) than the parent soil. The sorption of the chlorophenols on the soil and casts were well fitted to linear isotherms, with sorption capacity in the order of pentachlorophenol > 2,4-dichlorophenol > 2,4,6-trichlorophenol. The sorption on the cast with different aging time was quite similar and was higher than on the parent soil. The sorption on the soil did not change between pH 7.07 of the soil and pH 6.76 of the casts. The desorption hysteresis of the chlorophenols on the soil and casts was compound specific and 2,4,6-trichlorophenol showed the highest hysteresis. The higher sorption capacity of the casts was not owing to the lowered pH of the casts, but mainly to the higher fine particles in the casts and the possible changes of nature of the soil organic matter through the earthworm gut passage. Our results indicate that geophagous earthworms may change sorption behavior and thus the bioavailability and transport of chlorophenols in soil. Earthworm effects should be considered when evaluating the environmental behavior and risk of organic pollutants in the ecosystems where earthworms are abundant. PMID:21056454

  15. Earthworms, Collembola and residue management change wheat (Triticum aestivum) and herbivore pest performance (Aphidina: Rhophalosiphum padi).

    PubMed

    Ke, Xin; Scheu, Stefan

    2008-10-01

    Management practices of arable systems determine the distribution of soil organic matter thereby changing decomposer animal activity and their impact on nutrient mineralization, plant growth and plant-herbivore interactions. Decomposer-mediated changes in plant growth and insect pest performance were investigated in wheat-aphid model systems in the greenhouse. Three types of litter distribution were established: litter patch at the soil surface (simulating mulching), litter patch deeper in soil (simulating ploughing) and litter homogeneously mixed into soil (simulating disk cultivation). The litter was labelled with (15)N to follow the mineralization and uptake of nutrients by the plants. Earthworms (Aporrectodea caliginosa) and Collembola (Protaphorura armata) were included as representatives of major functional groups of decomposers. Wheat (Triticum aestivum) was planted and aphids (Rhophalosiphum padi) were introduced to leaves as one of the most important pests. Earthworms, Collembola and litter distribution affected plant growth, N acquisition and aphid development in an interactive way. Earthworms and Collembola increased biomass of seeds, shoots and roots of wheat. Increased plant growth by earthworms and Collembola was mainly due to increased transfer of N from soil (rather than litter) into plants. Despite increasing plant growth, earthworms reduced aphid reproduction. Aphid reproduction was not correlated closely with plant N concentrations, but rather with the concentration of litter N in wheat. Unexpectedly, both Collembola and earthworms predominantly affected the mobilization of N from soil organic matter, and by altering the distribution of litter earthworms reduced infestation of crops by aphids via reducing plant capture of litter N, in particular if the litter was concentrated deeper in soil. The results suggest that management practices stimulating a continuous moderate increase in nutrient mobilization from soil organic matter rather than nutrient flushes from decomposing fresh organic matter result in maximum plant growth with minimum plant pest infestation. PMID:18654802

  16. On the Causes of Avoidance.

    ERIC Educational Resources Information Center

    Han, Ho

    1998-01-01

    Investigates the cause of avoidance in learning negation in a Korean as a second-language (KSL) situation. Because Korean has two types of negatives--preverbal and postverbal--examination focused on whether students of KSL avoid a certain negative form, and if so, why. (Author/VWL)

  17. Cigarette tax avoidance and evasion.

    PubMed

    Stehr, Mark

    2005-03-01

    Variation in state cigarette taxes provides incentives for tax avoidance through smuggling, legal border crossing to low tax jurisdictions, or Internet purchasing. When taxes rise, tax paid sales of cigarettes will decline both because consumption will decrease and because tax avoidance will increase. The key innovation of this paper is to compare cigarette sales data to cigarette consumption data from the Behavioral Risk Factor Surveillance System (BRFSS). I show that after subtracting percent changes in consumption, residual percent changes in sales are associated with state cigarette tax changes implying the existence of tax avoidance. I estimate that the tax avoidance response to tax changes is at least twice the consumption response and that tax avoidance accounted for up to 9.6% of sales between 1985 and 2001. Because of the increase in tax avoidance, tax paid sales data understate the level of smoking and overstate the drop in smoking. I also find that the level of legal border crossing was very low relative to other forms of tax avoidance. If states have strong preferences for smoking control, they must pair high cigarette taxes with effective policies to curb smuggling and other forms of tax avoidance or employ alternative policies such as counter-advertising and smoking restrictions. PMID:15721046

  18. Behavioural inbreeding avoidance in wild African elephants.

    PubMed

    Archie, Elizabeth A; Hollister-Smith, Julie A; Poole, Joyce H; Lee, Phyllis C; Moss, Cynthia J; Maldonado, Jésus E; Fleischer, Robert C; Alberts, Susan C

    2007-10-01

    The costs of inbreeding depression, as well as the opportunity costs of inbreeding avoidance, determine whether and which mechanisms of inbreeding avoidance evolve. In African elephants, sex-biased dispersal does not lead to the complete separation of male and female relatives, and so individuals may experience selection to recognize kin and avoid inbreeding. However, because estrous females are rare and male-male competition for mates is intense, the opportunity costs of inbreeding avoidance may be high, particularly for males. Here we combine 28 years of behavioural and demographic data on wild elephants with genotypes from 545 adult females, adult males, and calves in Amboseli National Park, Kenya, to test the hypothesis that elephants engage in sexual behaviour and reproduction with relatives less often than expected by chance. We found support for this hypothesis: males engaged in proportionally fewer sexual behaviours and sired proportionally fewer offspring with females that were natal family members or close genetic relatives (both maternal and paternal) than they did with nonkin. We discuss the relevance of these results for understanding the evolution of inbreeding avoidance and for elephant conservation. PMID:17784925

  19. Avoidance of Phycomyces in a controlled environment.

    PubMed Central

    Meyer, P W; Matus, I J; Berg, H C

    1987-01-01

    The sporangiophore of the fungus Phycomyces bends away from nearby objects without ever touching them. It has been thought that these objects act as aerodynamic obstacles that damp random winds, thereby generating asymmetric distributions of a growth-promoting gas emitted by the growth zone. In the interest of testing this hypothesis, we studied avoidance in an environmental chamber in which convection was suppressed by a shallow thermal gradient. We also controlled pressure, temperature, and relative humidity of the air, electrostatic charge, and ambient light. A protocol was established that yielded avoidance rates constant from sporangiophore to sporangiophore to within +/- 10%. We found that avoidance occurred at normal rates in the complete absence of random winds. The rates were smaller at 100% than at lower values of relative humidity, but not by much. Remarkably, at a distance as great as 0.5 mm, avoidance from a 30-micron diam glass fiber (aligned parallel to the sporangiophore) was about the same as that from a planar glass sheet. However, the rate for the fiber fell more rapidly with distance. The rate for the sheet remained nearly constant out to approximately 4 mm. We conclude that avoidance depends either on adsorption by the barrier of a growth-inhibiting substance or emission by the barrier of a growth-promoting substance; it cannot occur by passive reflection. Models that can explain these effects are analyzed in the Appendix. PMID:3567313

  20. A survey of Pb, Cu, Zn, Cd, Cr, As, and Se in earthworms and soil from diverse sites

    USGS Publications Warehouse

    Beyer, W.N.; Cromartie, E.J.

    1987-01-01

    Earthworms and soils were collected from 20 diverse sites in Maryland, Pennsylvania, and Virginia, and were analyzed for Pb, Cu, Zn, Cd, Cr, As, and Se. Correlation coefficients relating Iconcentrations of the elements in earthworms to concentrations in soil were low (-0.20earthworms. The maximum concentrations of Pb (2100 ppm), Zn (1600 ppm), Cd (23 ppm) and Se (7.6 ppm) detected in earthworms were in the range reported to be toxic to animals fed diets containing these elements; however, even in the absence of any environmental contamination, some species of earthworms may contain high concentrations of Pb, Zn, and Se. Earthworms of the genus Eisenoides, for example, were exceptional in their ability to concentrate Pb. When earthworms are used as indicators of environmental contamination, it is important to identify the species, to report the soil characteristics, and to collect similar earthworms from very similar but uncontaminated soil.

  1. POPULATION DYNAMICS OF AMBIENT AND ALTERED EARTHWORM COMMUNITIES IN ROW-CROP AGROECOSYSTEMS IN THE MIDWESTERN U.S.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although earthworms affect agroecosystem processes, few studies have addressed population dynamics when earthworms are intentionally introduced. Therefore, handsorting and formalin extraction were used semi-annually from fall 1994 to fall 1997 to measure populations in ambient and addition plots in ...

  2. Functional and community-level soil microbial responses to zinc addition may depend on test system biocomplexity.

    PubMed

    Sverdrup, Line E; Linjordet, Roar; Strømman, Gjermund; Hagen, Snorre B; van Gestel, Cornelis A M; Frostegård, Sa; Sørheim, Roald

    2006-12-01

    The effect of zinc on soil nitrification and composition of the microbial community in soil was investigated using a full factorial experiment with five zinc concentrations and four levels of biological complexity (microbes only, microbes and earthworms (Eisenia fetida), microbes and Italian ryegrass (Lolium multiflorum var. Macho), and microbes, ryegrass and earthworms). After 6 weeks of exposure, the activity of soil nitrifying bacteria was measured and the microbial community structure was characterized by phospholipid fatty acid (PLFA) analysis. Soil nitrification and several PLFA markers were significantly influenced by either zinc addition and/or the presence of earthworms or ryegrass, and one of the most pronounced changes was the increase of fungi and decrease of bacteria with increasing concentrations of zinc. Of particular interest, however, was the potential interaction between the presence of plants and/or earthworms and the effect of zinc, which the factorial study design allowed us to explore. Such an effect was observed in two cases: Earthworms reduced the positive effect of zinc on the fungal biomass (ANOVA, p=0.03), and the effect of earthworms on the soil nitrification activity depended on zinc concentration (ANOVA, p<0.05). The effect of earthworm presence was not very large, but it does show that multispecies tests might give information about metal toxicity or bioavailability that cannot be predicted from single-species tests. PMID:16774777

  3. Stress synergy between environmentally realistic levels of copper and frost in the earthworm Dendrobaena octaedra.

    PubMed

    Bindesbøl, Anne-Mette; Holmstrup, Martin; Damgaard, Christian; Bayley, Mark

    2005-06-01

    In their natural habitat, animals are exposed to a variety of stress factors, including extreme temperatures, low water availability, and toxic stress from chemical pollutants. In this study we examined the interaction between realistic environmental levels of soil-copper contamination and realistic winter temperatures on survival of the cosmopolitan freeze-tolerant earthworm Dendrobaena octaedra. These interactions were tested using a full factorial design with six copper concentrations between 0 and 200 mg Cu/kg dry soil and five temperatures from +2 to -8 degrees C. A highly significant synergistic interaction existed that demonstrates that exposure to subzero temperatures significantly reduced copper tolerance and, conversely, that copper exposure significantly reduced freeze tolerance. Copper had no effect on glucose production, which is believed to be a major component of the cryoprotective system and the only known cryoprotectant in D. octaedra. This points to other mechanisms behind the observed synergy, possibly impaired osmoregulatory function of the cell membrane. The results support the working hypothesis that interactions between toxicants and dominant natural stress factors can alter the organisms' tolerance to these individual stressors. PMID:16117123

  4. Assessing the impact of triazine herbicides on organophosphate insecticide toxicity to the earthworm Eisenia fetida.

    PubMed

    Lydy, M J; Linck, S L

    2003-10-01

    A standard Organization for Economic Cooperation and Development (OECD) filter paper test was used to assess the acute toxicity of chlorpyrifos, atrazine, cyanazine, and simazine to the earthworm Eisenia fetida. Acute toxicity of chlorpyrifos was also determined in combination with the three-triazine herbicides. Surprisingly, atrazine and cyanazine caused mortality at concentrations lower than chlorpyrifos. Atrazine and cyanazine also increased the toxicity of chlorpyrifos 7.9- and 2.2-fold, respectively. However, simazine caused no toxicity to the worms and did not affect chlorpyrifos toxicity in binary mixture experiments. Possible mechanisms for the greater-than-additive toxicity for the binary combinations of atrazine and cyanazine with chlorpyrifos were investigated, including changes in uptake and biotransformation rates of chlorpyrifos in the presence of atrazine. Uptake of chlorpyrifos into the worms decreased slightly when atrazine was present in the system, therefore eliminating increased uptake as a possible explanation for the increased toxicity. Body residue analysis of worms indicated increased metabolite formation, suggesting the greater-than-additive response may be due to increased biotransformation to more toxic oxon metabolites. PMID:14674587

  5. Impact of Native and Invasive Earthworm Activity on Forest Soil Organic Matter Dynamics

    NASA Astrophysics Data System (ADS)

    Top, Sara; Filley, Timothy

    2010-05-01

    Many northern North American forests are experiencing the introduction of exotic European lumbricid species earthworms with documented losses in litter layers, expansion of A-horizons, loss of the organic horizon, changes in fine root density, and shifts in microbial populations as a result. Some of these forests were previously devoid of these ecosystem engineers. We compare the soil isotope and molecular chemistry from two free air CO2 enrichment (FACE) forest experiments (aspen FACE at Rhinelander, Wisconsin and sweet gum FACE at Oak Ridge National Lab, Tennessee) that lie within the zones of earthworm invasion. These sites exhibit differences in amounts of exotic and native species as well as endogeic (predominantly mineral soil dwelling) and epigeic (litter and organic matter horizon dwelling) types. We investigated the impact of earthworm activity by tracking the relative abundance and stable carbon isotope compositions of lignin and substituted fatty acids extracted from isolated earthworms and their fecal pellets and from host soils. Additionally, 15N-labeled additions to the soil provide additional methods for tracking earthworm impacts. Indications of root vs leaf input to earthworm casts and fecal matter were derived from differences in the chemical composition of cutin, suberin, and lignin. The isotopically depleted CO2 used in FACE and the resulting isotopically depleted plant organic matter afford an excellent opportunity to assess biopolymer-specific turnover dynamics. We find that endogeic species are proportionately more responsible for fine root cycling while some epigeic species are responsible for microaggregation of foliar cutin. CSIA of fecal pellet lignin and SFA indicate how these biopolymer pools can be derived from variable sources, roots, background soil, foliar tissue within one earthworm. Additionally, CSIA indicates the distinct roles that different earthworm types have in "aging" surface soil biopolymer pools through encapsulation and upward transport of deeper soil carbon, and "freshening" deeper soil biopolymer pools through downward transport of surface carbon to deeper layers. Although, endogeic species burrow down below 30 cm in these systems, comparison of 13C and 15N in soil layers and fecal matter indicate their greatest impact is restricted to the upper 5 cm. As earthworm species abundance and activity are not is steady state in these forests, the role of these important invertebrates should be more considered when assessing the ability of forest soils to accumulate new plant input.

  6. Effect of oral administration of Pheretima aspergillum (earthworm) in rats with cerebral infarction induced by middle-cerebral artery occlusion.

    PubMed

    Liu, Chung-Hsiang; Lin, Yi-Wen; Tang, Nou-Ying; Liu, Hsu-Jan; Huang, Chih-Yang; Hsieh, Ching-Liang

    2012-01-01

    We investigated the curative effect of Pheretima aspergillum (earthworm, PA) on rats with middle cerebral artery occlusion (MCAo). The MCAo-induced cerebral infarction was established and its underlying mechanisms by counting the infarction areas and evaluating the rats' neurological status. Immunostaining was used to test the expression of NeuN, and glial fibrillary acidic (GFAP), S100B, and brain-derived neurotrophic factor (BDNF) proteins. Our results showed that oral administration of PA for two weeks to rats with MCAo successfully reduced cerebral infarction areas in the cortex and striatum, and also reduced scores of neurological deficit. The PA-treated MCAo rats showed greatly decreased neuronal death, glial proliferation, and S100B proteins in the penumbra area of the cortex and in the ischemic core area of the cortex, but BDNF did not changed. These results demonstrated novel and detailed cellular mechanisms underlying the neuroprotective effects of PA in MCAo rats. PMID:24082328

  7. Effects of biochar on the transformation and earthworm bioaccumulation of organic pollutants in soil.

    PubMed

    Gu, Jianqiang; Zhou, Wenqiang; Jiang, Bingqi; Wang, Lianhong; Ma, Yini; Guo, Hongyan; Schulin, Rainer; Ji, Rong; Evangelou, Michael W H

    2016-02-01

    Little is known about the effects of biochar on the fate and behavior of micropollutants in soil, especially in the presence of soil macrofauna. Using a 14C-tracer, we studied the fate of 2,4-dichlorophenol and phenanthrene, after 30 days in soil in the presence of a biochar (0-5%, dry weight) produced from China fir at 400 °C and/or the earthworm Metaphire guillelmi. Application of the biochar significantly reduced the degradation and mineralization of both pollutants and strongly increased the accumulation of their metabolites in soil. The earthworm had no significant effects on the degradation of parent molecules of the pollutants but it significantly reduced the mineralization of the pollutants independent of the presence of the biochar. Although at an application rate of <1% the biochar strongly sorbed both pollutants, it did not significantly decrease the bioaccumulation of free dichlorophenol and phenanthrene and their metabolites by the earthworm. Our results demonstrate the complex effects of biochar on the fate, transformation, and earthworm bioaccumulation of organic pollutants in soil. They show that biochar application may not be an appropriate strategy for treating soil contaminated with hydrophobic organic pollutants and underline the importance of soil-feeding earthworms in risk assessments of biochar effects on soil remediation. PMID:26694792

  8. The Mechanics and Energetics of Soil Bioturbation by Plant Roots and Earthworms - Plastic Deformation Considerations

    NASA Astrophysics Data System (ADS)

    Ruiz, Siul; Or, Dani; Schymanski, Stanislaus

    2014-05-01

    Soil structure plays a critical factor in the agricultural, hydrological and ecological functions of soils. These services are adversely impacted by soil compaction, a damage that could last for many years until functional structure is restored. An important class of soil structural restoration processes are related to biomechanical activity associated with burrowing of earthworms and root proliferation in impacted soil volumes. We study details of the mechanical processes and energetics associated with quantifying the rates and mechanical energy required for soil structural restoration. We first consider plastic cavity expansion to describe earthworm and plant root radial expansion under various conditions. We then use cone penetration models as analogues to wedging induced by root tip growth and worm locomotion. The associated mechanical stresses and strains determine the mechanical energy associated with bioturbation for different hydration conditions and root/earthworm geometries. 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. The study provides the basic building blocks for estimating rates of soil structural alteration, the associated energetic requirements (soil carbon, plant assimilates) needed to sustain structure regeneration by earthworms and roots, and highlights potential mechanical cut-offs for such activities.

  9. Changes in forest floor composition and chemistry along an invasive earthworm gradient in a hardwood forest

    NASA Astrophysics Data System (ADS)

    Jourdain, J. N.; Filley, T. R.; Top, S. M.; Thayer, C.; Johnson, A.; Jenkins, M.; Welle, P.; Zurn-Birkhimer, S.; Kroeger, T.; Gemscholars

    2010-12-01

    Recent studies have demonstrated how invasive European earthworm species have caused large and long lasting perturbations to forest floor dynamics and soil composition in many northern hardwood forests. The type of perturbation is driven primarily by the composition and activity of the invasive species and the original state of the forest system. Over the past 4 years we have investigated an invasive earthworm front moving through the Ojibwa Red Lake Reservation (Minnesota). Significant shifts in litter and organic horizon mass were observed, similar to other gradients identified in the region, but the species of earthworms exhibited differences compared to other reservation lands in the region--possibly driven by the availability of recreation fishing near to the sites. Sharp gradients in earthworm abundance were observed exhibiting shifts from 600- 900 individuals per meter square to no observed worms within only 500 meters. The gradients in earthworm activity also influenced decay rates of litter, as was observed by placement of litter decay bags across the gradient. Our findings demonstrate the tenuous nature of many tribal reservation forests and point to the need for policies to address spread on such species to minimize impacts to soil carbon stocks as well as culturally important plant species.

  10. Cellular biomarkers for measuring toxicity of xenobiotics: Effects of polychlorinated biphenyls on earthworm Lumbricus terrestris coelomocytes

    SciTech Connect

    Goven, A.J.; Fitzpatrick, L.C. ); Eyambe, G.S. ); Venables, B.J. ); Cooper, E.L. )

    1993-05-01

    Acute toxicity in earthworms (Lumbricus terrestris) was assayed immediately after 5-d filter paper exposure to the polychlorinated biphenyl (PCB) Aroclor 1254, using coelomocyte viability, total extruded cell counts (ECC), differential cell counts (DCC), and formation of erythrocyte (ER) and secretory rosettes (SR) with, and phagocytosis of, antigenic rabbit red blood cells (RRBC). Chronic toxicity was assayed using rates by which earthworms replaced viable immunoactive coelomocytes, removed noninvasively immediately after exposure, over an 18-week depuration period. All cytological parameters, except ECC, were acutely affected immediately after exposure, when tissue concentrations were ([anti X] [plus minus] SE) 91.2 [plus minus] 8.19 [mu]g PCB per gram dry mass. Replacement of viable immunoactive coelomocytes occurred within six weeks in unexposed control earthworms. Exposed earthworms showed significant alteration in viability, ECC, DCC, ER, and SR formation, and phagocytosis at 6 and 12 weeks when PCB tissue concentrations were 41 [plus minus] 0.31 and 30.2 [plus minus] 0.88 [mu]g/g dry mass, respectively. Replacement of extruded coelomocytes with normal DCC of viable immunocompetent cells was not observed until week 18, when PCB had decreased to 15.7 [plus minus] 0.83 [mu]g/g dry mass. Low inherent natural variability in coelomocyte viability, ECC, DCC, rosette formation, and phagocytosis, and their sensitivity to sublethal PCB body burdens, indicated that earthworm coelomocytes have potential as nonmammalian biomarkers for assaying acute and chronic sublethal toxicity of xenobiotics.

  11. Earthworm genomes, genes and proteins: the (re)discovery of Darwin's worms

    PubMed Central

    Stürzenbaum, S.R.; Andre, J.; Kille, P.; Morgan, A.J.

    2008-01-01

    Small incremental biological change, winnowed by natural selection over geological time scales to produce large consequences, was Darwin's singular insight that revolutionized the life sciences. His publications after 1859, including the ‘earthworm book’, were all written to amplify and support the evolutionary theory presented in the Origin. Darwin was unable to provide a physical basis for the inheritance of favoured traits because of the absence of genetic knowledge that much later led to the ‘modern synthesis’. Mistaken though he was in advocating systemic ‘gemmules’ as agents of inheritance, Darwin was perceptive in seeking to underpin his core vision with concrete factors that both determine the nature of a trait in one generation and convey it to subsequent generations. This brief review evaluates the molecular genetic literature on earthworms published during the last decade, and casts light on the specific aspects of earthworm evolutionary biology that more or less engaged Darwin: (i) biogeography, (ii) species diversity, (iii) local adaptations and (iv) sensitivity. We predict that the current understanding will deepen with the announcement of a draft earthworm genome in Darwin's bicentenary year, 2009. Subsequently, the earthworm may be elevated from the status of a soil sentinel to that elusive entity, an ecologically relevant genetic model organism. PMID:19129111

  12. Stable strontium accumulation by earthworms: a paradigm for radiostrontium interactions with its cationic analogue, calcium.

    PubMed

    Morgan, J E; Richards, S P; Morgan, A J

    2001-06-01

    The accumulation of stable strontium and its chemical analogue calcium by four species of earthworm, representing three distinct ecophysiological groups inhabiting celestite (SrSO4)-rich natural soils, was investigated. An increase in soil strontium concentration over a four-orders-of-magnitude range was accompanied by an increase in earthworm tissue strontium concentration. In contrast, no relationship between soil and tissue calcium concentrations was apparent, indicating that this essential cation is strongly regulated within earthworm tissues but that nonessential strontium burdens are not physiologically regulated. Concentration factors for strontium ranged from 0.1 to 1.42, with an inverse relationship between this parameter and soil strontium concentration. The use of concentration factors and discrimination coefficients lead to the conclusion that earthworms discriminate against strontium accumulation at increased soil calcium concentrations, such that strontium would be predicted to be more efficiently accumulated by worms inhabiting acidic, calcium-poor soils. Although few consistent trends in strontium and calcium concentration were apparent between earthworm species, the species with the highest calcium turnover (i.e., the litter-inhabiting Lumbricus rubellus) typically accumulated higher concentrations of strontium than representatives of contrasting ecophysiological classes. These findings are considered in the context of the distribution, retention, and cycling of radiostrontium in soils. PMID:11392133

  13. The behavior and toxicological effects of decabromodiphenyl ether (BDE209) in a soil-earthworm system.

    PubMed

    Zhang, Wei; Li, Jing; Liu, Kou; Lin, Kuangfei

    2015-12-15

    Decabromodiphenyl ether (BDE209) is easily absorbed by soil particles but barely degraded over time. Its potential ecological risk has received extensive attention. Here we supplemented natural soil with three different levels of BDE209 (1, 10 and 100 mg kg(-1) dry weight (i.e., dw)) to focus on the behavior and toxicological effects of BDE209 in a soil-earthworm system. Results demonstrated that earthworms accumulated BDE209 quickly, followed by biphasic elimination. The uptake rate constant (ku) values ranged from 0.156 to 0.232 mg soil kg(-1)worm d(-1), while the depuration rate (kd) values ranged from 0.228 to 0.239 d(-1). Biota-soil accumulation factor (BSAF) was also calculated in the present study, and the BSAF values for BDE209 ranged from 0.074 to 0.123. Throughout 28-d exposure, the concentrations of BDE209 among soil, worm casts and earthworms reached steady-state equilibrium. BDE209 content in worm casts might be a good indicator of actual concentration in soil. Neutral red retention time (NRRT) was also conducted to assess the lysosomal membrane stability, and it declined during the uptake phase when BDE209 gradually accumulated in earthworms, indicating a good dose-response relationship. These observations provide new insights into the potential ecological effects of BDE209 in a model soil-earthworm system. PMID:26282772

  14. 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 eathworms 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 4days 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

  15. Edaphic factors affecting the toxicity and accumulation of arsenate in the earthworm Lumbricus terrestris

    SciTech Connect

    Meharg, A.A.; Shore, R.F.; Broadgate, K.

    1998-06-01

    The toxicity and accumulation of arsenate was determined in the earthworm Lumbricus terrestris in soil from different layers of a forest profile. Toxicity increased fourfold between 2 and 10 d. Edaphic factors (pH, soil organic matter, and depth in soil profile) also affected toxicity with a three fold decrease in the concentration that causes 50% mortality with increasing depth in soil. In a 4-d exposure study, there was no evidence of arsenic bioconcentration in earthworm tissue, although bioaccumulation was occurring. There was a considerable difference in tissue residues between living and dead earthworms, with dead worms having higher concentrations. This difference was dependent on both soil arsenate concentration and on soil type. Over a wide range of soil arsenate concentrations, earthworm arsenic residues are homeostatically maintained in living worms, but this homeostasis breaks down during death. Alternatively, equilibration with soil residues may occur via accumulation after death. In long-term accumulation studies in soils dosed with a sublethal arsenate concentration, bioconcentration of arsenate did not occur until day 12, after which earthworm concentrations rose steadily above the soil concentration, with residues in worms three fold higher than soil concentrations by the termination of the study. This bioconcentration only occurred in depurated worms over the time period of the study. Initially, depurated worms had lower arsenic concentrations than undepurated until tissue concentrations were equivalent to the soil concentration. Once tissue concentration was greater than soil concentration, depurated worms had higher arsenic residues than undepurated.

  16. Metabolism and bioaccumulation of nitroaromatic munitions by-products in earthworms and plants

    SciTech Connect

    Reddy, T.V.; Chang, L.W.; Smith, M.K.; Daniel, F.B.; Wiechman, B.; Reddy, G.

    1994-12-31

    Previously the authors have used earthworm and plant bioassays to evaluate the toxicity of nitroaromatic ammunition by-products. In the present study, they investigated the uptake, metabolism and possible bioaccumulation of these compounds in earthworms and plants. Earthworms were maintained on artificial soil supplemented with {sup 14}[C] trinitrobenzene (TNB). The authors also studied the translocation, metabolism and bioaccumulation of {sup 14}[C] 1,3-dinitrobenzene (DNB) by germinating oat and lettuce seeds planted on artificial soil. Acetone extracts of tissue and gut contents of earthworms exposed to TNB for different intervals contained only a small fraction of the original radioactivity, which did not increase with time. The radioactivity extracted from earthworms co-eluted with 1,3-dinitroaniline (DNAN) on HPLC and the amount of radioactivity decreased with time. In the DNB plant studies, five day old oat seedlings accumulated 17% of {sup 14}[C] radioactivity. HPLC of acetone extracts revealed unidentified radioactive peaks but DNB radioactivity was not detected. The radioactivity from butanol extracts of both oats and lettuce coeluted with aniline and 3-nitroaniline and the radioactivity increased with time. These results suggest that oats and lettuce bioaccumulate DNB metabolites, which might result in the transfer of toxicants to herbivores.

  17. Effect of Earthworm Feeding Guilds on Ingested Dissimilatory Nitrate Reducers and Denitrifiers in the Alimentary Canal of the Earthworm ▿ †

    PubMed Central

    Depkat-Jakob, Peter S.; Hilgarth, Maik; Horn, Marcus A.; Drake, Harold L.

    2010-01-01

    The earthworm gut is an anoxic nitrous oxide (N2O)-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 N2O 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

  18. Assessing ecotoxicity and uptake of metals and metalloids in relation to two different earthworm species (Eiseina hortensis and Lumbricus terrestris).

    PubMed

    Leveque, Thibaut; Capowiez, Yvan; Schreck, Eva; Mazzia, Christophe; Auffan, Mélanie; Foucault, Yann; Austruy, Annabelle; Dumat, Camille

    2013-08-01

    Due to diffuse atmospheric fallouts of process particles enriched by metals and metalloids, polluted soils concern large areas at the global scale. Useful tools to assess ecotoxicity induced by these polluted soils are therefore needed. Earthworms are currently used as biotest, however the influence of specie and earthworm behaviour, soil characteristics are poorly highlighted. Our aim was therefore to assess the toxicity of various polluted soils with process particles enriches by metals and metalloids (Pb, Cd, Cu, Zn, As and Sb) collected from a lead recycling facility on two earthworm species belonging to different ecological types and thus likely to have contrasted behavioural responses (Eiseina hortensis and Lumbricus terrestris). The combination of behavioural factors measurements (cast production and biomass) and physico-chemical parameters such as metal absorption, bioaccumulation by earthworms and their localization in invertebrate tissues provided a valuable indication of pollutant bioavailability and ecotoxicity. Soil characteristics influenced ecotoxicity and metal uptake by earthworms, as well as their soil bioturbation. PMID:23688736

  19. Neutral red retention by lysosomes from earthworm (Lumbricus rubellus) coelomocytes: A simple biomarker of exposure to soil copper

    SciTech Connect

    Weeks, J.M.; Svendsen, C.

    1996-10-01

    A simple subcellular histochemical staining technique employing the lysosomal probe neutral red has been developed for use with the epiendogeic earthworm Lumbricus rubellus Hoffmeister. Coelomocytes extracted from the coelomic cavity of earthworms into an isotonic earthworm Ringer solution were allowed to adhere to a microscope slide for 30 s before the application of a neutral red dye. This red dye was rapidly accumulated within the lysosomes. Observation of the loss of this dye from these lysosomes into the surrounding cytosol has enabled the quantification of the degree of lysosomal damage caused to earthworms with exposure to an increasing range of soil copper concentrations, in both laboratory and mesocosm studies. This simple in vitro biomarker has potential for the rapid assessment of the toxic effects to earthworms from soils contaminated with heavy metals and metalloids.

  20. Converging evidence of social avoidant behavior in schizophrenia from two approach-avoidance tasks.

    PubMed

    de la Asuncion, Javier; Docx, Lise; Sabbe, Bernard; Morrens, Manuel; de Bruijn, Ellen R A

    2015-10-01

    Many people with schizophrenia suffer from social impairments characterized by active social avoidance, which is related to social phobia common in schizophrenia, while motivational impairments can also result in passive social withdrawal. Although social avoidance is frequently reported in this population, this is the first study to directly compare approach-avoidance tendencies in schizophrenia patients (N = 37) and healthy controls (N = 29). Participants performed two tasks: a computerized approach-avoidance task (AAT) to assess response tendencies toward images of happy and angry faces with direct or averted gaze and a one-to-one personal space test (PST) to gauge more naturalistic approach-avoidance behaviors toward a real person bearing a neutral expression. The AAT results showed that both groups showed faster avoidance responses to angry faces and faster approach responses to happy faces with a direct gaze. Happy faces with averted gaze, however, resulted in faster avoidance responses in the patient group only. On the PST, the patients approached the experimenter less than healthy controls did. This measure of interpersonal distance was positively related to positive symptom severity. Delusions of reference and increased sensitivity to social rejection may explain the patients' avoidance tendencies in response to pictures of happy faces with averted gaze and in the presence of an actual person. The current findings demonstrate the importance of others adopting positive and unambiguous attitudes when interacting with schizophrenia patients to minimize behavioral avoidance patterns, which is particularly relevant for relatives and clinicians whose interactions with the patients are crucial to facilitating treatment and promoting healthy social relationships. PMID:26343605

  1. Redistribution and Destabilization of Forest Soil Carbon by Earthworm Invasion

    NASA Astrophysics Data System (ADS)

    Swanston, C. W.; Torn, M. S.; Allen, L.; Lilleskov, E. A.; Maggi, F.

    2008-12-01

    Soils of temperate forests in the northern Great Lakes region have developed in the absence of earthworms, which were largely eradicated during the last ice age. European earthworms, such as Lumbricus terrestris, are spreading and their effect on forest soil C has not been widely studied. We examined soils along a chronosequence of worm activity (wormosequence) ranging from no apparent activity (Low) to high activity over several decades (High). In the soil profile, including organic horizons, there was only a small loss (4%) of C with high worm activity. There was a 71% decrease in the Oe and no remaining Oa in the High site. Conversely, the mineral soil contained 25% more C in the High site, with most of that in the top 20 cm. We densimetrically separated the mineral soil into primarily organic free light fraction (FLF) and occluded light fraction (OLF), a mineral-associated intermediate fraction (IF), and a mineral-associated dense fraction (DF). We measured fraction mass, C, nitrogen, and 14C content. In comparison to Low sites, each depth of High worm soil had less FLF C and more IF C. With worms, more C was stored in aggregates in the upper soil but less in the lower soil. The presence of worms had a very large effect on the 14C content of soil organic matter, with shifts of > 60 per mil in several fractions presumably due to a combination of vertical redistribution and more rapid transfer into and out of some fractions. For example, from the Low to High sites OLF 14C increased 100 per mil at 0-10 cm depth, while DF 14C decreased 80 per mil at 20-50 cm. The effect of worms on C cycling can be explored using a multi-pool, multi-depth model that treats 14C as a conservative (i.e., stable) tracer. Our results suggest that worms play a major role in redistributing soil C in these forest soils by pathways that differ with depth: the upper soil loses FLF C and incorporates organic horizon C into OLF and IF, whereas in the lower depths FLF is lost and the previously stable OLF C pool is redistributed into IF and DF. We conclude that the introduction of worms to these forest soils has fundamentally changed the storage, distribution, and turnover of soil organic C.

  2. Dietary flexibility aids Asian earthworm invasion in North American forests.

    PubMed

    Zhang, Weixin; Hendrix, Paul F; Snyder, Bruce A; Molina, Marirosa; Li, Jianxiong; Rao, Xingquan; Siemann, Evan; Fu, Shenglei

    2010-07-01

    On a local scale, invasiveness of introduced species and invasibility of habitats together determine invasion success. A key issue in invasion ecology has been how to quantify the contribution of species invasiveness and habitat invasibility separately. Conventional approaches, such as comparing the differences in traits and/or impacts of species between native and/or invaded ranges, do not determine the extent to which the performance of invaders is due to either the effects of species traits or habitat characteristics. Here we explore the interaction between two of the most widespread earthworm invaders in the world (Asian Amynthas agrestis and European Lumbricus rubellus) and study the effects of species invasiveness and habitat invasibility separately through an alternative approach of "third habitat" in Tennessee, USA. We propose that feeding behaviors of earthworms will be critical to invasion success because trophic ecology of invasive animals plays a key role in the invasion process. We found that (1) the biomass and isotopic abundances (delta13C and delta15N) of A. agrestis were not impacted by either direct effects of L. rubellus competition or indirect effects of L. rubellus-preconditioned habitat; (2) A. agrestis disrupted the relationship between L. rubellus and soil microorganisms and consequently hindered litter consumption by L. rubellus; and (3) compared to L. rubellus, A. agrestis shifted its diet more readily to consume more litter, more soil gram-positive (G+) bacteria (which may be important for litter digestion), and more non-microbial soil fauna when soil microorganisms were depleted. In conclusion, A. agrestis showed strong invasiveness through its dietary flexibility through diet shifting and superior feeding behavior and its indirectly negative effect of habitat invasibility on L. rubellus via changes in the soil microorganism community. In such context, our results expand on the resource fluctuation hypothesis and support the superior competitor hypothesis. This work presents additional approaches in invasion ecology, provides some new dimensions for further research, and contributes to a greater understanding of the importance of interactions between multiple invading species. PMID:20715629

  3. Signal Molecules Mediate the Impact of the Earthworm Aporrectodea caliginosa on Growth, Development and Defence of the Plant Arabidopsis thaliana

    PubMed Central

    Puga-Freitas, Ruben; Barot, Sébastien; Taconnat, Ludivine; Renou, Jean-Pierre; Blouin, Manuel

    2012-01-01

    Earthworms have generally a positive impact on plant growth, which is often attributed to a trophic mechanism: namely, earthworms increase the release of mineral nutrients from soil litter and organic matter. An alternative hypothesis has been proposed since the discovery of a signal molecule (Indole Acetic Acid) in earthworm faeces. In this study, we used methodologies developed in plant science to gain information on ecological mechanisms involved in plant-earthworm interaction, by looking at plant response to earthworm presence at a molecular level. First, we looked at plant overall response to earthworm faeces in an in vitro device where only signal molecules could have an effect on plant growth; we observed that earthworms were inducing positive or negative effects on different plant species. Then, using an Arabidopsis thaliana mutant with an impaired auxin transport, we demonstrated the potential of earthworms to stimulate root growth and to revert the dwarf mutant phenotype. Finally, we performed a comparative transcriptomic analysis of Arabidopsis thaliana in the presence and absence of earthworms; we found that genes modulated in the presence of earthworms are known to respond to biotic and abiotic stresses, or to the application of exogenous hormones. A comparison of our results with other studies found in databases revealed strong analogies with systemic resistance, induced by signal molecules emitted by Plant Growth Promoting Rhizobacteria and/or elicitors emitted by non-virulent pathogens. Signal molecules such as auxin and ethylene, which are considered as major in plant-microorganisms interactions, can also be of prior importance to explain plant-macroinvertebrates interactions. This could imply revisiting ecological theories which generally stress on the role of trophic relationships. PMID:23226498

  4. Vision-based obstacle avoidance

    DOEpatents

    Galbraith, John

    2006-07-18

    A method for allowing a robot to avoid objects along a programmed path: first, a field of view for an electronic imager of the robot is established along a path where the electronic imager obtains the object location information within the field of view; second, a population coded control signal is then derived from the object location information and is transmitted to the robot; finally, the robot then responds to the control signal and avoids the detected object.

  5. Immune system participates in brain regeneration and restoration of reproduction in the earthworm Dendrobaena veneta.

    PubMed

    Molnar, Laszlo; Pollak, Edit; Skopek, Zuzanna; Gutt, Ewa; Kruk, Jerzy; Morgan, A John; Plytycz, Barbara

    2015-10-01

    Earthworm decerebration causes temporary inhibition of reproduction which is mediated by certain brain-derived neurohormones; thus, cocoon production is an apposite supravital marker of neurosecretory center functional recovery during brain regeneration. The core aim of the present study was to investigate aspects of the interactions of nervous and immune systems during brain regeneration in adult Dendrobaena veneta (Annelida; Oligochaeta). Surgical brain extirpation was combined, either with (i) maintenance of immune-competent coelomic cells (coelomocytes) achieved by surgery on prilocaine-anesthetized worms or (ii) prior extrusion of fluid-suspended coelomocytes by electrostimulation. Both brain renewal and cocoon output recovery were significantly faster in earthworms with relatively undisturbed coelomocyte counts compared with individuals where coelomocyte counts had been experimentally depleted. These observations provide empirical evidence that coelomocytes and/or coelomocyte-derived factors (e.g. riboflavin) participate in brain regeneration and, by implication, that there is close functional synergy between earthworm neural and immune systems. PMID:25863277

  6. [The composition of phospholipid and biosynthesis of platelet-activating factor in earthworm (Eisenia foetida)].

    PubMed

    Cheng, N N; Sugiura, T; Fukuda, T; Waku, K

    1992-01-01

    Platelet-activating factor (PAF) was for the first time confirmed to exist in a lower animal, earthworm (Eisenia foetida). It amounts to 10.7 +/- 6.1 pmol/g wet body weight, and varied seasonally. Phospholipid analysis revealed that 1-O-alkyl-2-acyl-sn-glycerophosphocholine, a stored form of PAF precursor, accounted for 61.4% of the choline glycerophospholipids. Two kinds of enzyme activities operating in PAF generation in mammalian cells were also detected from this species. The PAF level increased markedly under some injurious stimuli such as cutting and pricking. The results suggest that PAF may be a primary mediator involved in pathological and physiological reactions even in lower animal like earthworm. The findings also cast a new light on the mechanisms underlying the antihypertensive and other effects of the Chinese medicinal earthworm, pheretima. PMID:1299136

  7. Long-term persistence of dieldrin, DDT, and heptachlor epoxide in earthworms

    USGS Publications Warehouse

    Beyer, W.N.; Krynitsky, A.J.

    1989-01-01

    Earthworms can accumulate persistent soilborne insecticides and are an important source of contamination of terrestrail wildlife. We treated experimental plots once with dieldrin, DDT, or heptachlor, and measured changes in insecticide concentrations in earthworms over a 20-year period. We estimated 'half-times,' defined as the time for a concentration in earthworms to be reduced by half. Deldrin had a half-time of 5.4 years. DDE, the metabolite of DDT most important to wildlife, increased until the third year and then decreased with a half-time of 5.7 years. Heptachlor epoxide, the metabolite of hepatachlor most important to wildlife, increased until the second year and then decreased with a half-time of 4.3 years. The declining parts of the curves of all three compounds fit exponential decay equations reasonably well. The estimates persistence are relevant to insecticides at low or moderate concentrations in relatively undistrubed soils in temperate climates.

  8. [Organic waste treatment by earthworm vermicomposting and larvae bioconversion: review and perspective].

    PubMed

    Zhang, Zhi-jian; Liu, Meng; Zhu, Jun

    2013-05-01

    There is a growing attention on the environmental pollution and loss of potential regeneration of resources due to the poor handling of organic wastes, while earthworm vermicomposting and larvae bioconversion are well-known as two promising biotechnologies for sustainable wastes treatments, where earthworms or housefly larvae are employed to convert the organic wastes into humus like material, together with value-added worm product. Taken earthworm ( Eisenia foetida) and housefly larvae ( Musca domestica) as model species, this work illustrates fundamental definition and principle, operational process, technical mechanism, main factors, and bio-chemical features of organisms of these two technologies. Integrated with the physical and biochemical mechanisms, processes of biomass conversion, intestinal digestion, enzyme degradation and microflora decomposition are comprehensively reviewed on waste treatments with purposes of waste reduction, value-addition, and stabilization. PMID:23914515

  9. Predator Avoidance in Extremophile Fish

    PubMed Central

    Bierbach, David; Schulte, Matthias; Herrmann, Nina; Zimmer, Claudia; Arias-Rodriguez, Lenin; Indy, Jeane Rimber; Riesch, Rüdiger; Plath, Martin

    2013-01-01

    Extreme habitats are often characterized by reduced predation pressures, thus representing refuges for the inhabiting species. The present study was designed to investigate predator avoidance of extremophile populations of Poecilia mexicana and P. sulphuraria that either live in hydrogen sulfide-rich (sulfidic) springs or cave habitats, both of which are known to have impoverished piscine predator regimes. Focal fishes that inhabited sulfidic springs showed slightly weaker avoidance reactions when presented with several naturally occurring predatory cichlids, but strongest differences to populations from non-sulfidic habitats were found in a decreased shoaling tendency with non-predatory swordtail (Xiphophorus hellerii) females. When comparing avoidance reactions between P. mexicana from a sulfidic cave (Cueva del Azufre) and the adjacent sulfidic surface creek (El Azufre), we found only slight differences in predator avoidance, but surface fish reacted much more strongly to the non-predatory cichlid Vieja bifasciata. Our third experiment was designed to disentangle learned from innate effects of predator recognition. We compared laboratory-reared (i.e., predator-naïve) and wild-caught (i.e., predator-experienced) individuals of P. mexicana from a non-sulfidic river and found no differences in their reaction towards the presented predators. Overall, our results indicate (1) that predator avoidance is still functional in extremophile Poecilia spp. and (2) that predator recognition and avoidance reactions have a strong genetic basis. PMID:25371337

  10. Proposed annex to the ASTM Standard Guide E1676-95, bioaccumulation testing utilizing Eisenia foetida

    SciTech Connect

    Roper, J.; Simmers, J.; Lee, C.; Tatem, H.

    1995-12-31

    A detailed description of the method developed at the Waterways Experiment Station (WES) to determine sediment toxicity utilizing the earthworm, Eisenia foetida. This method has been used successfully in evaluating the target contaminants; metals, PAHs, and PCBs. This procedure is currently a proposed annex to the ASTM Standard Guide E1676-95: Conducting a Laboratory Soil Toxicity Test With The Lumbricid Earthworm, Eisenia foetida.

  11. Effects of earthworm invasion on plant species richness in northern hardwood forests.

    PubMed

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

    2007-08-01

    The invasion of non-native earthworms (Lumbricus spp.) into a small number of intensively studied stands of northern hardwood forest has been linked to declines in plant diversity and the local extirpation of one threatened species. It is unknown, however, whether these changes have occurred across larger regions of hardwood forests, which plant species are most vulnerable, or with which earthworm species such changes are associated most closely. To address these issues we conducted a regional survey in the Chippewa and Chequamegon national forests in Minnesota and Wisconsin (U.S.A.), respectively. We sampled earthworms, soils, and vegetation, examined deer browse in 20 mature, sugar-maple-dominated forest stands in each national forest, and analyzed the relationship between invasive earthworms and vascular plant species richness and composition. Invasion by Lumbricus was a strong indicator of reduced plant richness in both national forests. The mass of Lumbricus juveniles was significantly and negatively related to plant-species richness in both forests. In addition, Lumbricus was a significant factor affecting plant richness in a full model that included multiple variables. In the Chequamegon National Forest earthworm mass was associated with higher sedge cover and lower cover of sugar maple seedlings and several forb species. The trends were similar but not as pronounced in Chippewa, perhaps due to lower deer densities and different earthworm species composition. Our results provide regional evidence that invasion by Lumbricus species may be an important mechanism in reduced plant-species richness and changes in plant communities in mature forests dominated by sugar maples. PMID:17650250

  12. Balkanized research in ecological engineering revealed by a bibliometric analysis of earthworms and ecosystem services.

    PubMed

    Blouin, Manuel; Sery, Nicolas; Cluzeau, Daniel; Brun, Jean-Jacques; Bédécarrats, Alain

    2013-08-01

    Energy crisis, climate changes, and biodiversity losses have reinforced the drive for more ecologically-based approaches for environmental management. Such approaches are characterized by the use of organisms rather than energy-consuming technologies. Although earthworms are believed to be potentially useful organisms for managing ecosystem services, there is actually no quantification of such a trend in literature. This bibliometric analysis aimed to measure the evolution of the association of "earthworms" and other terms such as ecosystem services (primary production, nutrient cycling, carbon sequestration, soil structure, and pollution remediation), "ecological engineering" or "biodiversity," to assess their convergence or divergence through time. In this aim, we calculated the similarity index, an indicator of the paradigmatic proximity defined in applied epistemology, for each year between 1900 and 2009. We documented the scientific fields and the geographical origins of the studies, as well as the land uses, and compare these characteristics with a 25 years old review on earthworm management. The association of earthworm related keywords with ecosystem services related keywords was increasing with time, reflecting the growing interest in earthworm use in biodiversity and ecosystem services management. Conversely, no significant increase in the association between earthworms and disciplines such as ecological engineering or restoration ecology was observed. This demonstrated that general ecologically-based approaches have yet to emerge and that there is little exchange of knowledge, methods or concepts among balkanized application realms. Nevertheless, there is a strong need for crossing the frontiers between fields of application and for developing an umbrella discipline to provide a framework for the use of organisms to manage ecosystem services. PMID:23716007

  13. Influence of earthworm activity on gene transfer from Pseudomonas fluorescens to indigenous soil bacteria.

    PubMed Central

    Daane, L L; Molina, J A; Berry, E C; Sadowsky, M J

    1996-01-01

    We have developed a model system to assess the influence of earthworm activity on the transfer of plasmid pJP4 from an inoculated donor bacterium, Pseudomonas fluorescens C5t (pJP4), to indigenous soil microorganisms. Three different earthworm species (Lumbricus terrestris, Lumbricus rubellus, and Aporrectodea trapezoides), each with unique burrowing, casting, and feeding behaviors, were evaluated. Soil columns were inoculated on the surface with 10(8) cells per g of soil of the donor bacterium, and after a 2-week incubation period, donor, transconjugant, and total bacteria were enumerated at 5-cm-depth intervals. Transconjugants were confirmed by use of colony hybridization with a mer gene probe. In situ gene transfer of plasmid pJP4 from P. fluorescens C5t to indigenous soil bacteria was detected in all inoculated microcosms. In the absence of earthworms, the depth of recovery was limited to the top 5 cm of the column, with approximately 10(3) transconjugants per g of soil. However, the total number of transconjugants recovered from soil was significantly greater in microcosms containing either L. rubellus or A. trapezoides, with levels reaching about 10(5) CFU/g of soil. In addition, earthworms distributed donor and transconjugant bacteria throughout the microcosm columns, with the depth of recovery dependent on the burrowing behavior of each earthworm species. Donor and transconjugant bacteria were also recovered from earthworm casts and inside developing cocoons. Transconjugant bacteria from the indigenous soil microflora were classified as belonging to Acidovorax spp., Acinetobacter spp., Agrobacterium spp., Pasteurella spp., Pseudomonas spp., and Xanthomonas spp. PMID:8593052

  14. [Comparative studies on vermicomposting of sewage sludge with two epigeic earthworms].

    PubMed

    Chen, Xue-min; Huang, Kui; Fu, Xiao-yong; Ni, Shao-ren

    2010-05-01

    A comparative study was conducted two epigeic species earthworms (Bimastus parvus and Eisenia foetida) for the evaluation of their efficacy in vermicomposting of sewage sludge. The various changes studied during pot experiments were the physiochemical properties of the sewage sludge, sludge reduction and earthworm biomass. Vermicomposting resulted that both epigeic species earthworms showed same capability among sewage sludge mineralization and decomposition rate and reduction. By the end of experiment, the pH value declined to 6.27 with B. parvus and 7.07 with E. foetida, but both epigeic species earthworms showed same mineralization and decomposition rate. B. parvus produced 31.96%, 5.76% and 17.91% increases in nitrogen, phosphorus, and potassium as well as 44.14% and 30.69% decreases in C/N and C/P ratios as compared to initial after 30 days of inoculation. In contrast, E. foetida produced 35.48% and 11.58% increases in nitrogen and potassium as well as 10.12%, 46.73% and 20.50% decreases in phosphorus, C/N and C/P ratios as compared to initial after 30 days of earthworm activity. At the same time, both epigeic species earthworms resulted in significant reduction in heavy metal content. The reduction in heavy metal content for B. parvus and E. foetida was found in the order: Zn > Cu > Pb > Cr and Cu > Zn > Ph > Cr. At the end of experiment, the weight and cocoons of B. parvus and E. foetida showed significant increase, which the growth rate and the reproductive rate were 76%-86% and 156%-131% respectively. PMID:20623864

  15. Balkanized Research in Ecological Engineering Revealed by a Bibliometric Analysis of Earthworms and Ecosystem Services

    NASA Astrophysics Data System (ADS)

    Blouin, Manuel; Sery, Nicolas; Cluzeau, Daniel; Brun, Jean-Jacques; Bédécarrats, Alain

    2013-08-01

    Energy crisis, climate changes, and biodiversity losses have reinforced the drive for more ecologically-based approaches for environmental management. Such approaches are characterized by the use of organisms rather than energy-consuming technologies. Although earthworms are believed to be potentially useful organisms for managing ecosystem services, there is actually no quantification of such a trend in literature. This bibliometric analysis aimed to measure the evolution of the association of "earthworms" and other terms such as ecosystem services (primary production, nutrient cycling, carbon sequestration, soil structure, and pollution remediation), "ecological engineering" or "biodiversity," to assess their convergence or divergence through time. In this aim, we calculated the similarity index, an indicator of the paradigmatic proximity defined in applied epistemology, for each year between 1900 and 2009. We documented the scientific fields and the geographical origins of the studies, as well as the land uses, and compare these characteristics with a 25 years old review on earthworm management. The association of earthworm related keywords with ecosystem services related keywords was increasing with time, reflecting the growing interest in earthworm use in biodiversity and ecosystem services management. Conversely, no significant increase in the association between earthworms and disciplines such as ecological engineering or restoration ecology was observed. This demonstrated that general ecologically-based approaches have yet to emerge and that there is little exchange of knowledge, methods or concepts among balkanized application realms. Nevertheless, there is a strong need for crossing the frontiers between fields of application and for developing an umbrella discipline to provide a framework for the use of organisms to manage ecosystem services.

  16. Snakes mimic earthworms: propulsion using rectilinear travelling waves.

    PubMed

    Marvi, Hamidreza; Bridges, Jacob; Hu, David L

    2013-07-01

    In rectilinear locomotion, snakes propel themselves using unidirectional travelling waves of muscular contraction, in a style similar to earthworms. In this combined experimental and theoretical study, we film rectilinear locomotion of three species of snakes, including red-tailed boa constrictors, Dumeril's boas and Gaboon vipers. The kinematics of a snake's extension-contraction travelling wave are characterized by wave frequency, amplitude and speed. We find wave frequency increases with increasing body size, an opposite trend than that for legged animals. We predict body speed with 73-97% accuracy using a mathematical model of a one-dimensional n-linked crawler that uses friction as the dominant propulsive force. We apply our model to show snakes have optimal wave frequencies: higher values increase Froude number causing the snake to slip; smaller values decrease thrust and so body speed. Other choices of kinematic variables, such as wave amplitude, are suboptimal and appear to be limited by anatomical constraints. Our model also shows that local body lifting increases a snake's speed by 31 per cent, demonstrating that rectilinear locomotion benefits from vertical motion similar to walking. PMID:23635494

  17. Snakes mimic earthworms: propulsion using rectilinear travelling waves

    PubMed Central

    Marvi, Hamidreza; Bridges, Jacob; Hu, David L.

    2013-01-01

    In rectilinear locomotion, snakes propel themselves using unidirectional travelling waves of muscular contraction, in a style similar to earthworms. In this combined experimental and theoretical study, we film rectilinear locomotion of three species of snakes, including red-tailed boa constrictors, Dumeril's boas and Gaboon vipers. The kinematics of a snake's extension–contraction travelling wave are characterized by wave frequency, amplitude and speed. We find wave frequency increases with increasing body size, an opposite trend than that for legged animals. We predict body speed with 73–97% accuracy using a mathematical model of a one-dimensional n-linked crawler that uses friction as the dominant propulsive force. We apply our model to show snakes have optimal wave frequencies: higher values increase Froude number causing the snake to slip; smaller values decrease thrust and so body speed. Other choices of kinematic variables, such as wave amplitude, are suboptimal and appear to be limited by anatomical constraints. Our model also shows that local body lifting increases a snake's speed by 31 per cent, demonstrating that rectilinear locomotion benefits from vertical motion similar to walking. PMID:23635494

  18. Earthworm-based miniature robot for intestinal inspection

    NASA Astrophysics Data System (ADS)

    Chi, Dongxiang; Yan, Guozheng

    2001-10-01

    As a part of MIS (Minimally Invasive Surgery), the endoscope plays an important role in the field of diagnosis and treatment. To combine a miniature robot with an endoscope is a new dimension in the field of medical robotics in recent years. Overcoming the shortcomings of the traditional endoscope, robotic endoscope applies new materials and technologies into the design of a endoscope and booms the development of a new type of endoscope. In this paper, an earthworm based electromagnetic robotic endoscope system is introduced whose structure and locomotion mechanism are analyzed. The motion characteristics in time and frequency domain of a single component are also discussed in detail and a modified waveform and a suitable driving frequency are put forward through which an effective movement control can be achieved and the heat generation of the robot reduced. The robot, 7mm in diameter, 64mm in length and 9.8g in weight, is small enough to pass through the neck of intestine easily and flexible enough (gimbal mounts of 2 degree of freedom) to wind through the intestine. Though the running of the robot is good, there are still problems, such as heat generation and locomotion mechanism on the inner intestinal surface, to be solved.

  19. Cold acclimation and lipid composition in the earthworm Dendrobaena octaedra.

    PubMed

    Holmstrup, Martin; Sørensen, Louise I; Bindesbøl, Anne-Mette; Hedlund, Katarina

    2007-08-01

    We have investigated the lipid chemistry during cold acclimation in the freeze tolerant earthworm Dendrobaena octaedra. The dominant phospholipid fatty acids (PLFA) of D. octaedra were 20:4, 20:5 and 20:1 (50% of total PLFA) followed by 18:0, 18:1 and 18:2omega6,9 (25% of total PLFA). The ability to tolerate freezing in this species was acquired after acclimation at low temperature for 2-4 weeks. During this period one particular membrane PLFA, 18:2omega6,9, increased significantly and there was a good correlation between the proportion of this PLFA and the survival of freezing. The composition of neutral lipid fatty acids (NLFA), most likely representing storage lipids (triacylglycerides), also changed during cold acclimation so that the overall degree of unsaturation increased. Using a common-garden experiment approach, we compared lipid composition of three genetically different populations (Denmark, Finland and Greenland) that differed in their freeze tolerance. Inter-populational differences and differences due to cold acclimation in overall fatty acid composition were evident in both PLFAs and NLFAs. Specifically, the PLFAs, 20:4 and 20:5, were considerably more represented in worms from Greenland, and this contributed to a higher UI of PLFAs in this population. PMID:17383915

  20. Rock phosphate solubilizing and cellulolytic actinomycete isolates of earthworm casts

    NASA Astrophysics Data System (ADS)

    Mba, Caroline C.

    1994-03-01

    Four microbial isolates, OP2, OP3, OP6, and OP7, of earthworm casts of Pontoscolex corethrurus were found to be acid tolerant actinomycetes and efficient rock phosphate (RP) solubilizers that could grow fast on NH4Cl-enriched or N-free carboxymethyl cellulose or glucose as sole carbon source. CMC (carboxymethyl cellulose) induced production of extracellular cellulase enzyme and the production of reducing sugar in all the isolates. RP solubilizing power was observed to be inversely related to glucose consumption. The most efficient RP solubilizer was found to consume the least glucose. Growth was faster on cellulose than on glucose media. N-free CMC induced greater glucose production than NH4Cl-enriched CMC medium. Both CMC and glucose media were acidified by all the isolates, however, RP solubilizing power decreased with acidification. Solubilization power was greatest with isolate OP7, which also produced the greatest amount of reducing sugar per gram CMC. Both RP solubilizing power and the cellulolytic efficiency varied among isolates. A minimum of 631 µg P/0.1 g RP and a maximum of 951.4 µg P/0.1 g RP was recorded.

  1. Metallothionein gene activation in the earthworm (Lumbricus rubellus)

    PubMed Central

    Höckner, M.; Dallinger, R.; Stürzenbaum, S.R.

    2015-01-01

    In order to cope with changing environmental conditions, organisms require highly responsive stress mechanisms. Heavy metal stress is handled by metallothioneins (MTs), the regulation of which is evolutionary conserved in insects and vertebrates and involves the binding of metal transcription factor 1 (MTF-1) to metal responsive elements (MREs) positioned in the promoter of MT genes. However, in most invertebrate phyla, the transcriptional activation of MTs is different and the exact mechanism is still unknown. Interestingly, although MREs are typically present also in invertebrate MT gene promoters, MTF-1 is notably absent. Here we use Lumbricus rubellus, the red earthworm, to study the elusive mechanism of wMT-2 activation in control and Cd-exposed conditions. EMSA and DNase I footprinting approaches were used to pinpoint functional binding sites within the wMT-2 promoter region, which revealed that the cAMP responsive element (CRE) is a promising candidate which may act as a transcriptional activator of invertebrate MTs. PMID:25797623

  2. Earthworms newly from Mongolia (Oligochaeta, Lumbricidae, Eisenia)

    PubMed Central

    Blakemore, Robert J.

    2013-01-01

    Abstract 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

  3. Visualization of enzyme activities inside earthworm biopores by in situ soil zymography

    NASA Astrophysics Data System (ADS)

    Thu Duyen Hoang, Thi; Razavi, Bahar. S.; Blagodatskaya, Evgenia; Kuzyakov, Yakov

    2015-04-01

    Earthworms can strongly activate microorganisms, increase microbial and enzyme activities and consequently the turnover of native soil organic matter. In extremely dynamic microhabitats and hotspots as biopores made by earthworms, the in situ enzyme activities are a footprint of complex biotic interactions. The effect of earthworms on the alteration of enzyme activities inside biopores and the difference between bio-pores and earthworm-free soil was visualized by in situ soil zymography (Spohn and Kuzyakov, 2014). For the first time, we prepared quantitative imaging of enzyme activities in biopores. Furthermore, we developed the zymography technique by direct application of a substrate saturated membrane to the soil to obtain better spatial resolution. Lumbricus terrestris L. was placed into transparent box (15×20×15cm). Simultaneously, maize seed was sown in the soil. Control soil box with maize and without earthworm was prepared in the same way. After two weeks when bio-pore systems were formed by earthworm, we visualized in situ enzyme activities of five hydrolytic enzymes (β-glucosidase, cellobiohydrolase, chitinase, xylanase, leucine aminopeptidase) and phosphatase. Followed by non-destructive zymography, biopore samples and control soil were destructively collected to assay enzyme kinetics by fluorogenically labeled substrates method. Zymography showed higher activity of β-glucosidase, chitinase, xylanase and phosphatase in biopores comparing to bulk soil. These differences were further confirmed by fluorimetric microplate enzyme assay detected significant difference of Vmax in four above mentioned enzymes. Vmax of β-glucosidase, chitinase, xylanase and phosphatase in biopores is 68%, 108%, 50% and 49% higher than that of control soil. However, no difference in cellobiohydrolase and leucine aminopeptidase kinetics between biopores and control soil were detected. This indicated little effect of earthworms on protein and cellulose transformation in soil. In conclusion, earthworms contribute to the decomposition of carbohydrates through promoting enzyme activities involved in the C-cycle except for leucine aminopeptidase and cellobiohydrolase. 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

  4. Potentiation effect of metolachlor on toxicity of organochlorine and organophosphate insecticides in earthworm Eisenia andrei.

    PubMed

    Stepi?, Sandra; Hackenberger, Branimir K; Velki, Mirna; Hackenberger, Davorka K; Lon?ari?, Zeljka

    2013-07-01

    Acetylcholinesterase, glutathione-S-transferase and catalase activities were determined in earthworms Eisenia andrei exposed to insecticides (endosulfan, temephos, malathion, pirimiphos-methyl) alone and in a binary combination with the herbicide metolachlor. Metolachlor individually was not acutely toxic, even at high concentrations applied; however, in the treated earthworms metolachlor enhanced the toxicity of endosulfan and temephos by significantly reducing the acetylcholinesterase activity. In binary combination with malathion and pirimiphos-methyl, metolachlor did not increase toxicity. The potentiation character of metolachlor is specific rather than general, and probably depends on the chemical structure of pesticides in the mixture. PMID:23666323

  5. Earthworms and litter management contributions to ecosystem services in a tropical agroforestry system.

    PubMed

    Fonte, Steven J; Six, Johan

    2010-06-01

    The development of sustainable agricultural systems depends in part upon improved management of non-crop species to enhance the overall functioning and provision of services by agroecosystems. To address this need, our research examined the role of earthworms and litter management on nutrient dynamics, soil organic matter (SOM) stabilization, and crop growth in the Quesungual agroforestry system of western Honduras. Field mesocosms were established with two earthworm treatments (0 vs. 8 Pontoscolex corethrurus individuals per mesocosm) and four litter quality treatments: (1) low-quality Zea mays, (2) high-quality Diphysa robinioides, (3) a mixture of low- and high-quality litters, and (4) a control with no organic residues applied. Mesocosms included a single Z. mays plant and additions of 15N-labeled inorganic nitrogen. At maize harvest, surface soils (0-15 cm) in the mesocosms were sampled to determine total and available P as well as the distribution of C, N, and 15N among different aggregate-associated SOM pools. Maize plants were divided into grain and non-grain components and analyzed for total P, N, and 15N. Earthworm additions improved soil structure as demonstrated by a 10% increase in mean weight diameter and higher C and N storage within large macro-aggregates (>2000 microm). A corresponding 17% increase in C contained in micro-aggregates within the macro-aggregates indicates that earthworms enhance the stabilization of SOM in these soils; however, this effect only occurred when organic residues were applied. Earthworms also decreased available P and total soil P, indicating that earthworms may facilitate the loss of labile P added to this system. Earthworms decreased the recovery of fertilizer-derived N in the soil but increased the uptake of 15N by maize by 7%. Litter treatments yielded minimal effects on soil properties and plant growth. Our results indicate that the application of litter inputs and proper management of earthworm populations can have important implications for the provision of ecosystem services (e.g., C sequestration, soil fertility, and plant production) by tropical agroforestry systems. PMID:20597290

  6. Perspectives in avoidance-preference bioassays

    SciTech Connect

    Steele, C.W.; Taylor, D.H.; Strickler-Shaw, S.

    1996-12-31

    Although behavioral endpoints are used in hazard assessment, establishment of water quality criteria and assessment of a contaminant`s hazard to aquatic life rely primarily on standard acute and chronic toxicity tests. Sublethal effects of pollutants should, however, be of major concern because more organisms experience sublethal rather than acutely or chronically lethal exposures of contaminants. The avoidance-preference approach to behavioral bioassays is very useful in screening pollutants for which the mechanisms of perception or response are largely unknown. The underlying philosophy of these studies is that an animal which perceives a chemical can be attracted or repulsed by it. No response is frequently assumed to indicate lack of perception. All three responses have broad ecological implications. The authors discuss the conditions required for performing avoidance-preference bioassays, as well as their sensitivities, advantages, and limitations. In this regard, a comparative approach is used in examining the results of avoidance-preference bioassays with zebrafish in two different apparatuses. Finally, they compare the results of avoidance-preference studies with other measures of the behavioral toxicity of lead to tadpoles.

  7. Passive Avoidance Is Linked to Impaired Fear Extinction in Humans

    ERIC Educational Resources Information Center

    Cornwell, Brian R.; Overstreet, Cassie; Krimsky, Marissa; Grillon, Christian

    2013-01-01

    Conventional wisdom dictates we must face our fears to conquer them. This idea is embodied in exposure-based treatments for anxiety disorders, where the intent of exposure is to reverse a history of avoidant behavior that is thought to fuel a patient's irrational fears. We tested in humans the relationship between fear and avoidance by combining…

  8. Avoidance behavior of young black ducks treated with chromium

    USGS Publications Warehouse

    Heinz, G.H.; Haseltine, S.D.

    1981-01-01

    Pairs of adult black ducks (Anas rubripes) were fed a diet containing 0, 20, or 200 ppm chromium in the form of chromium potassium sulfate. Ducklings from these pairs were fed the same diets as adults and were tested for their avoidance responses to a fright stimulus. Neither level of chromium had a significant effect on avoidance behavior.

  9. A Comparison of "Direct" versus "Derived" Extinction of Avoidance Responding

    ERIC Educational Resources Information Center

    Roche, Bryan T.; Kanter, Jonathan W.; Brown, Keri R.; Dymond, Simon; Fogarty, Ciara C.

    2008-01-01

    To establish a series of derived relations between arbitrary stimuli, 20 subjects were exposed to nonarbitrary and arbitrary relational training and testing procedures. Subjects were then exposed to an avoidance conditioning procedure in which one member from each relation was established as a discriminative stimulus for avoidance and…

  10. Passive Avoidance Is Linked to Impaired Fear Extinction in Humans

    ERIC Educational Resources Information Center

    Cornwell, Brian R.; Overstreet, Cassie; Krimsky, Marissa; Grillon, Christian

    2013-01-01

    Conventional wisdom dictates we must face our fears to conquer them. This idea is embodied in exposure-based treatments for anxiety disorders, where the intent of exposure is to reverse a history of avoidant behavior that is thought to fuel a patient's irrational fears. We tested in humans the relationship between fear and avoidance by combining…

  11. Avoided cost standard under PURPA

    SciTech Connect

    Cole, R.J.; Holmlund, I.; Smith, S.A.; Williams, T.A.

    1983-04-01

    The Public Utility Regulatory Policies Act (PURPA) (P.L. 95-617) was passed to encourage electricity conservation through a variety of regulatory and rate reforms. Information is provided on the controversy surrounding the avoided cost standard established under PURPA. Promulgated by the Federal Energy Regulatory Committee (FERC) in February 1980, the avoided cost standard sets a minimum rate for utilities purchasing power from a qualified facility (QF) at the utilities full avoided cost. Recent court cases have challenged this standard and FERC is currently appealing to the Supreme Court. The impact of these court cases may have little effect on the actual rates set by state Public Utility Commissions (PUCs), which can require rates higher than the minimums established by FERC, since many PUCs appear in favor of requiring full avoided costs. The arguments for and against requiring utilities to pay full avoided costs come down to balancing between incentives for QFs on the one hand and fairness to utilities and their non-QF customers on the other.

  12. Approach/avoidance in dreams.

    PubMed

    Malcolm-Smith, Susan; Koopowitz, Sheri; Pantelis, Eleni; Solms, Mark

    2012-03-01

    The influential threat simulation theory (TST) asserts that dreaming yields adaptive advantage by providing a virtual environment in which threat-avoidance may be safely rehearsed. We have previously found the incidence of biologically threatening dreams to be around 20%, with successful threat avoidance occurring in approximately one-fifth of such dreams. TST asserts that threat avoidance is over-represented relative to other possible dream contents. To begin assessing this issue, we contrasted the incidence of 'avoidance' dreams with that of their opposite: 'approach' dreams. Because TST states that the threat-avoidance function is only fully activated in ecologically valid (biologically threatening) contexts, we also performed this contrast for populations living in both high- and low-threat environments. We find that 'approach' dreams are significantly more prevalent across both contexts. We suggest these results are more consistent with the view that dreaming is generated by reward-seeking systems than by fear-conditioning systems, although reward-seeking is clearly not the only factor determining the content of dreams. PMID:22196966

  13. Avoiding versus seeking: the relationship of information seeking to avoidance, blunting, coping, dissonance, and related concepts*

    PubMed Central

    Case, Donald O.; Andrews, James E.; Johnson, J. David; Allard, Suzanne L.

    2005-01-01

    Question: How have theorists and empirical researchers treated the human tendency to avoid discomforting information? Data Sources: A historical review (1890–2004) of theory literature in communication and information studies, coupled with searches of recent studies on uptake of genetic testing and on coping strategies of cancer patients, was performed. Study Selection: The authors' review of the recent literature included searches of the MEDLINE, PsychInfo, and CINAHL databases between 1992 and summer of 2004 and selective, manual searches of earlier literature. Search strategies included the following subject headings and key words: MeSH headings: Genetic Screening/psychology, Decision Making, Neoplasms/diagnosis/genetics/psychology; CINAHL headings: Genetic Screening, Genetic Counseling, Anxiety, Decision Making, Decision Making/Patient; additional key words: avoidance, worry, monitoring, blunting, cancer. The “Related Articles” function in MEDLINE was used to perform additional “citation pearl” searching. Main Results: The assumption that individuals actively seek information underlies much of psychological theory and communication practice, as well as most models of the infor