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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

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.

Yeardley, R.B. Jr.; Gast, L.C. [DynCorp, Cincinnati, OH (United States); Lazorchak, J.M. [Environmental Protection Agency, Cincinnati, OH (United States)

1996-09-01

3

Earthworm avoidance of biochar can be mitigated by wetting  

Microsoft Academic Search

Biochar has a great potential for enhancing soil fertility and carbon sequestration while enabling beneficial waste disposition. Because of the potential for widespread application, it is essential to proactively assess and mitigate any unintended consequences associated with soil biochar amendment. We conducted soil avoidance tests, growth and reproduction tests, and oxidative stress assays with the earthworm Eisenia foetida to assess

Dong Li; William C. Hockaday; Caroline A. Masiello; Pedro J. J. Alvarez

2011-01-01

4

Experiences with Novel Approaches in Earthworm Testing Alternatives (7 pp)  

Microsoft Academic Search

Goal, Scope and Background. The earthworm avoidance test is a sensitive screening test. Currently, two test designs, a twochamber system and a six-chamber system, are under standardization. In the scope of the present study, the two test systems are compared. To assess the results, two procedures are applied, which are based on a threshold value and a statistical method. Moreover,

Kerstin Hund-Rinke; Monika Lindemann; Markus Simon

2005-01-01

5

Toxicity of copper and zinc assessed with three different earthworm tests  

Microsoft Academic Search

At present, standardised earthworm acute toxicity and reproduction tests are used to assess the toxicity of heavy metal contaminated soils. These tests are, however, time-consuming, laborious and costly, and in addition, some sublethal responses may remain overlooked. Avoidance of metal contaminated soils by earthworms may be a useful parameter when assessing ecological risks with a low test effort. The objective

Tuomas Lukkari; Marjo Aatsinki; Ari Väisänen; Jari Haimi

2005-01-01

6

Contact tests for pentachlorophenol toxicity to earthworms  

SciTech Connect

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.

Spontak, D.A. [Utah State Univ., Logan, UT (United States)

1994-12-31

7

Earthworms  

Microsoft Academic Search

Along with concern for environmental quality and the anticipated return to an appropriate technology by highly developed nations, it behooves us not to ignore such natural forces — as the earthworm — that have made possible our existence as managers of the Earth. In order to plan for the future use (and exploitation) of earthworms, an understanding of their biology

John M. Laird; Manfred Kroger; M. R. Heddleson

1981-01-01

8

Earthworm  

NSDL National Science Digital Library

Earthworms like to live underground in the moist soil. Two reasons why they are considered to be annelids are because they have a segmented body and they lack true legs. They have soft bodies and as a result don't have any "armor" to protect them. Earthworms can dry up and die after being out of the soil too long or they can easily be eaten by insects, as in the picture.

N/A N/A (None;)

2004-07-06

9

Effects of decabromodiphenyl ether (BDE-209) on the avoidance response, survival, growth and reproduction of earthworms (Eisenia fetida).  

PubMed

The effects of decabromodiphenyl ether (BDE-209) on avoidance response, survival, growth, and reproduction of earthworms (Eisenia fetida) were investigated under laboratory conditions using natural and artificial soils as substrate. Results showed that no significant avoidance response was observed when earthworms were exposed to 0.1-1000 mg/kg of BDE-209 for 48 h. After 28-days exposure, no significant effects on survival and growth of adult earthworms was induced by 0.1-1000 mg/kg of BDE-209 indicating the Lowest Observed Effect Level (LOEL) of BDE-209 on their survival and body weight was more than 1000 mg/kg. Except for a significant decrease in the number of juveniles per hatched cocoon in artificial soils at 1000 mg/kg of BDE-209, no significant effects on reproductive parameters (e.g. cocoon production per earthworms, weight per cocoon and cocoon hatchability) were observed. These results suggest that adult earthworms have a strong tolerance for BDE-209 exposure in soils, but a potential toxicity does exist for earthworm embryos or juveniles. PMID:23312040

Xie, Xianchuan; Qian, Yan; Wu, Yingxin; Yin, Jun; Zhai, Jianping

2013-04-01

10

Relating results from earthworm toxicity tests to agricultural soil  

USGS Publications Warehouse

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.

Beyer, W.N.

1992-01-01

11

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

Microsoft Academic Search

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

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

1999-01-01

12

Differences in toxicity of the insecticide chlorpyrifos to six species of earthworms (Oligochaeta, Lumbricidae) in standardized soil tests  

Microsoft Academic Search

The choice of the earthworm species for use in the laboratory screening of chemicals remains a matter of controversy. The earthworm Eisenia fetida has been specified as a test species in current international standards for testing the acute lethality of chemicals to earthworms (OECD 1984; EEC 1985). E.fetida is a compost-dwelling species convenient for captive breeding. However, its ecological representativeness

Wei-chun Ma; Jos Bodt

1993-01-01

13

Earthworm avoidance of biochar can be mitigated by wetting , William C. Hockaday b  

E-print Network

to assess the potential toxicity of soil amended with biochar produced from apple wood chips. Earthworms hydrocarbons (PAHs) formed during biochar production by pyrolysis. Nutrition deficiency was excluded by pyrolysis of carbon-rich biomass, draws tremendous interest worldwide due to its potential to enhance soil

Alvarez, Pedro J.

14

Field tests on the side effects of pesticides on earthworms: Influence of plot size and cultivation practices  

Microsoft Academic Search

Standardized field tests, which ran for up to one year, were used to investigate the side effects of pesticides on earthworms under agricultural conditions. The studies were run on 10 × 10 m replicate plots of flat, uniform grassland areas. Benomyl was used as a reference substance. To exclude migration of earthworms from untreated plots to plots where earthworm abundance

Fred Heimbach

1997-01-01

15

Dynamic study of the burrowing behaviour of Aporrectodea nocturna and Allolobophora chlorotica : interactions between earthworms and spatial avoidance of burrows  

Microsoft Academic Search

The behaviour of earthworms belonging to two different species and ecological types (Aporrectodea nocturna and Allolobophora chlorotica) was studied using two-dimensional (2D) terraria. Two experiments were set up to gain insight into the nature of interactions between these earthworms. Firstly, the evolution of the burrow systems was analysed with the density of the earthworms varying from one to five individuals.

Y. Capowiez; L. Belzunces

2001-01-01

16

ACAT Ground Collision Avoidance Flight Tests Over  

NASA Video Gallery

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

17

Flight Tests Validate Collision-Avoidance System  

NASA Video Gallery

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

18

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

Microsoft Academic Search

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

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

1989-01-01

19

Limit-test toxicity screening of selected inorganic nanoparticles to the earthworm Eisenia fetida  

Microsoft Academic Search

The toxicity of a range of inorganic (Ag, Cu, Ni, Al2O3, SiO2, TiO2 and ZrO2) nanoparticles (NP) and their corresponding metal salt or bulk metal oxide were screened for toxicity toward the earthworm\\u000a Eisenia fetida using the limit-test design (1000 mg\\/kg). This study provides the first ecotoxicological life history trait data on earthworms\\u000a for each these NPs, as well as for

Lars-Henrik Heckmann; Mads B. Hovgaard; Duncan S. Sutherland; Herman Autrup; Flemming Besenbacher; Janeck J. Scott-Fordsmand

2011-01-01

20

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...

21

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

SciTech Connect

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.

Stewart, A.J.; Wicker, L.F.; Nazerias, M.S. [Oak Ridge National Lab., TN (United States)

1995-12-31

22

Using earthworm avoidance behaviour to assess the toxicity of formulated herbicides and their active ingredients on natural soils  

Microsoft Academic Search

Background, aim, and scope  Soil quality has been threatened by intensive agricultural practises, namely those relying on the application of pesticides,\\u000a such as herbicides. Among the non-target terrestrial organisms exposed to such scenarios, earthworms are key ecological receptors\\u000a widely used in ecotoxicological studies. As such, this work aims to assess the effects of two herbicide active ingredients\\u000a (a.i.)—sulcotrione and penoxsulam—and their

Catarina Marques; Ruth Pereira; Fernando Gonçalves

2009-01-01

23

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

PubMed

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

Sheppard, S C; Stephenson, G L

2012-01-01

24

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

SciTech Connect

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.

Stephenson, G.L. [Univ. of Guelph, Ontario (Canada); Scroggins, R. [Environment Canada, Gloucester, Ontario (Canada). Method Development and Application Section

1995-12-31

25

Recycled water sources influence the bioavailability of copper to earthworms.  

PubMed

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

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

2013-10-15

26

Twenty Common Testing Mistakes for EFL Teachers to Avoid  

ERIC Educational Resources Information Center

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

Henning, Grant

2012-01-01

27

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

PubMed

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

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

2012-07-01

28

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

PubMed

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

Pelosi, C; Joimel, S; Makowski, D

2013-01-01

29

Short Communication AVOIDANCE, WEIGHT LOSS, AND COCOON PRODUCTION ASSESSMENT FOR  

E-print Network

Short Communication AVOIDANCE, WEIGHT LOSS, AND COCOON PRODUCTION ASSESSMENT FOR EISENIA FETIDA) was hindered only at very high C60 concentrations (5% by weight), and C60 (up to 1%) was not avoided and did;30:2542­2545. # 2011 SETAC Keywords--Earthworm Avoidance test Reproduction Nanoparticle Ecotoxicity INTRODUCTION

Alvarez, Pedro J.

30

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

SciTech Connect

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.

Yeardley, R.B. Jr. [DynCorp-TAI, Cincinnati, OH (United States); Lazorchak, J.M. [Environmental Protection Agency, Cincinnati, OH (United States); Pence, M.A. [Technology Applications, Inc., Cincinnati, OH (United States)

1995-07-01

31

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

SciTech Connect

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.

van Gestel, C.A.; van Dis, W.A.; van Breemen, E.M.; Sparenburg, P.M. (National Institute of Public Health and Environmental Protection, BA Bilthoven (Netherland))

1989-12-01

32

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

SciTech Connect

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).

Van Gestel, C.A.; Dirven-Van Breemen, E.M.; Baerselman, R.; Emans, H.J.; Janssen, J.A.; Postuma, R.; Van Vliet, P.J. (National Institute of Public Health and Environmental Protection, Bilthoven, (Netherlands))

1992-04-01

33

Longitudinal in vivo MR imaging of live earthworms.  

PubMed

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. J. Exp. Zool. 321A: 479-489, 2014. © 2014 Wiley Periodicals, Inc. PMID:25059556

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

2014-11-01

34

Comparison of biological and chemical measures of metal bioavailability in field soils: test of a novel simulated earthworm gut extraction.  

PubMed

Bioavailability of metals in soil is a major factor influencing estimates of risk associated with exposure of ecological receptors. Metal concentrations in soil are often compared to ecological screening benchmarks, which are based on total concentrations in soil. Often, the total concentration is not correlated with toxicity. No standardised method exists for determining the bioavailability of metals in soil to ecological receptors. Several surrogate measures of bioavailability were compared to the results of a battery of toxicity tests using copper (Cu), lead (Pb), and zinc (Zn)-contaminated soils collected from a former industrial area. A calcium chloride (CaCl(2)) extraction, cyclodextrin (HPCD) extraction, simulated earthworm gut (SEG) test, and earthworm bioaccumulation test were performed using the soils. Extractable metals using the CaCl(2) solution were not correlated with any biological responses of earthworms (Eisenia andrei), collembola (Folsomia candida), northern wheatgrass (Elymus lanceolatus), or alfalfa (Medicago sativa L.). Concentrations of metals in the HPCD extracts were highly variable and were not adequate for revealing adverse effects. E. andrei tissue concentrations were variable but were predictive of adverse effects to invertebrates. The results of the SEG test correlated with most of the biological endpoints. Bioavailable Cu was correlated with adverse effects to invertebrates and plants using the SEG test. Overall, coefficients of determination associated with the relationships between the biological responses and each measure of bioavailability indicated that those for the SEG test were greater than those for the other surrogate measures of bioavailability. Further validation is required before this test is routinely used to estimate metal bioavailability and toxicity. PMID:20678790

Smith, Ben A; Greenberg, Bruce; Stephenson, Gladys L

2010-10-01

35

Linking litter calcium, earthworms and soil properties: a common garden test with 14 tree  

E-print Network

concentrations among tree species resulted in profound changes in soil acidity and fertility that were similar earthworm abundance and diversity, as well as increased soil pH, exchangeable calcium, per cent base knowledge of how tree species affect soils is because of the fact that plant species distribution patterns

Chorover, Jon

36

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

PubMed Central

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

2013-01-01

37

The influence of different artificial soil types on the acute toxicity of carbendazim to the earthworm Eisenia fetida in laboratory toxicity tests  

Microsoft Academic Search

Field populations of earthworms have shown a varied response in mortality to the fungicide carbendazim, the toxic reference substance used in agrochemical field trials. The aim of this study was to determine the influence of soil conditions as a potential cause of this variation. Laboratory acute toxicity tests were conducted using a range of artificial soils with varying soil components

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

2007-01-01

38

A comparison of nickel toxicity to pre-exposed earthworms ( Eisenia fetida, oligochaeta) in two different test substrates  

Microsoft Academic Search

Earthworms are soil living organisms of high ecological importance. For that reason, earthworms can be considered as feasible biological indicators for many pollutants in soils. Soils are extremely complex and dynamic systems influenced by a number of different abiotic and biological factors determining the effects of potentially toxic substances. To be able to evaluate the toxicity of a single substance

Rudolf A. Maleri; Adriaan J. Reinecke; Sophiè A. Reinecke

2007-01-01

39

Teacher's Guide for Earthworms.  

ERIC Educational Resources Information Center

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…

Bruno, Merle S.; And Others

40

Chronic toxicity of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) in soil determined using the earthworm ( Eisenia andrei) reproduction test  

Microsoft Academic Search

The sublethal and chronic effects of the environmental contaminant and explosive octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) in artificial soil were assessed using the earthworm (Eisenia andrei). Based on various reproduction parameters (total and hatched number of cocoons, number of juveniles and their biomass), fecundity was reduced at the different concentrations of HMX tested (from 280.0±12.3 to 2502.9±230.0 mg kg?1 dry soil) in spiked

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

2001-01-01

41

Can earthworms survive fire retardants?  

USGS Publications Warehouse

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.

Beyer, W.N.; Olson, A.

1996-01-01

42

Unexpected earthworm effects on forest understory plants  

PubMed Central

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

2013-01-01

43

Earthworm in the 21st century  

NASA Astrophysics Data System (ADS)

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.

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

2010-05-01

44

Approach\\/Avoidance motives, test emotions, and emotional regulation related to testing  

Microsoft Academic Search

This research stems from our program of work that focuses on understanding how students regulated their emotions related to testing. The primary goal for this study was to incorporate the approach\\/avoidance motives into a model of emotional regulation related to testing. In addition, a secondary goal was to report on efforts at construct validation of the scores obtained during the

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

2008-01-01

45

Earthworms and soil fertility  

Microsoft Academic Search

Summary Earthworms redistribute organic materials within the soil, increase soil penetrability and, und certain conditions, influence ion transport in soils. Root distribution may be modified and microbial activity increased by their burrowing and feeding activities. Earthworms influence the supply of nutrients in several ways. Not only is earthworm tissue and cast material enriched in certain nutrients, relative to the soil

J. K. Syers; J. A. Springett

1984-01-01

46

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

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

Nunes, Maria Edna Tenório; Espíndola, Evaldo Luiz Gaeta

2012-05-01

47

Amino acids in earthworms: Are earthworms ecosystemivorous?  

Microsoft Academic Search

Amino acid contents were studied in eight earthworm species (Lumbricus rubellus, L. terrestris, Nicodrilus roseus, N. caliginosus, Dendrobaena octaedra, Eisenia nordenskioldi, Octolasium lacteum, Drawida ghilarovi), plant litter and soil. There are considerable differences in the content of essential amino acids between earthworms and their food (for most amino acids, one order of magnitude; for methionine, up to two orders of

Andrei D. Pokarzhevskii; Dmitrii P. Zaboyev; Gennadii N. Ganin; Stella A. Gordienko

1997-01-01

48

Earthworms and Soil Pollutants  

PubMed Central

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

Hirano, Takeshi; Tamae, Kazuyoshi

2011-01-01

49

Accident Avoidance Skill Training and Performance Testing. Final Report.  

ERIC Educational Resources Information Center

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…

Hatterick, G. Richard; Barthurst, James R.

50

Accumulation of chlorinated benzenes in earthworms  

USGS Publications Warehouse

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. This paper describes a long-term (26 week) experiment relating the concentrations of chlorinated benzenes in earthworms to 1) the length of exposure, and it describes three 8-week experiments relating concentrations of chlorinated benzenes in earthworms to 2) their concentration in soil 3) the soil organic matter content and, 4) the degree of chlorination. In the 26-week experiment, the concentration of 1,2,4 - trichlorobenzene in earthworms fluctuated only slightly about a mean of 0.63 ppm (Fig. 1). Although a statistically significant decrease can be demonstrated over the test (Pearson correlation coefficient, r = -0.62 p < 0.05), the decrease was minor. Hexachlorobenzene in earthworms showed a cyclical trend that coincided with replacement of the media, and a slight but statistically significant tendency to increase from about 2 to 3 ppm over the 26 weeks (r = 0.55, p < 0.05). Concentrations of both trichlorobenzene and hexachlorobenzene in earthworms increased as the concentrations in the soil increased (Fig. 2), but leveled off at the highest soil concentrations. The most surprising result of this study was the relatively low concentrations in earthworms compared to those in soils. The average concentration of each of the six isomers of trichlorobenzene and tetrachlorobenzene in earthworms was only about 1 ppm (Table 2); the isomeric structure did not affect accumulation. The concentration of organic matter in soil had a prominent effect on hexachlorobenzene concentrations in earthworms (Fig. 3). Hexachlorobenzene concentrations decreased steadily from 9.3 ppm in earthworms kept in soil without any peat moss added to about 1 ppm in soil containing 16 or 32% organic matter.

Beyer, W.N.

1996-01-01

51

Development of an alternative artificial soil for earthworm toxicity testing in tropical countries  

Microsoft Academic Search

The standard soil invertebrate toxicity tests developed by OECD and ISO use an artificial soil as the test substrate, which contains sphagnum peat as a component. This type of peat is not widely available. Investigation of possible alternative substrates using locally available materials therefore is vital for performing such ecotoxicity tests, particularly in the tropics. We studied the suitability of

Cornelis A. M. van Gestel

2009-01-01

52

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

ERIC Educational Resources Information Center

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)

Switzer, Paul V.; Fritz, Ann H.

2001-01-01

53

Earthworms lost from pesticides application in potato crops  

NASA Astrophysics Data System (ADS)

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.

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

2010-05-01

54

Avoidance and reproduction tests with the predatory mite Hypoaspis aculeifer: effects of different chemical substances.  

PubMed

Few toxicity data exist in the literature on the toxicity of chemicals to the predatory mite Hypoaspis aculeifer, but no information is available on its avoidance response. To assess the relevance of the avoidance behavior of H. aculeifer and the relative sensitivity of the mite in comparison with other invertebrates, avoidance and reproduction tests were conducted with 7 chemicals using standardized guidelines. The chemicals (deltamethrin, chloropyrifos, dimethoate, Cu, NaCl, phenanthrene, and boric acid) were selected so as to cover varying chemical classes. For all 3 pesticides tested, avoidance response showed lower sensitivity than reproduction and survival (avoidance median effective concentration [EC50] > reproduction EC50/median lethal concentration [LC50] values). However, for Cu, NaCl, and phenanthrene, the avoidance response showed similar sensitivity as reproduction (avoidance EC50 ? reproduction EC50 values), whereas for boric acid, similar sensitivity as survival (avoidance EC50 ? LC50 values). Although the mite H. aculeifer appears less sensitive to some of the chemicals tested than most other soil invertebrates, its status as the only predator among organisms for which standardized tests are available affirms its inclusion in routine ecotoxicity assessment. The results of the avoidance test with H. aculeifer suggest its potential usefulness as a rapid screening test for risk assessment purposes. PMID:24122914

Owojori, Olugbenga J; Waszak, Karolina; Roembke, Joerg

2014-01-01

55

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

PubMed

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

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

2003-01-01

56

Effects of silver nanoparticles (NM-300K) on Lumbricus rubellus earthworms and particle characterization in relevant test matrices including soil.  

PubMed

The impact of silver nanoparticles (AgNP; at 0 mg Ag/kg, 1.5 mg Ag/kg, 15.4 mg Ag/kg, and 154 mg Ag/kg soil) and silver nitrate (AgNO3 ; 15.4 mg Ag/kg soil) on earthworms, Lumbricus rubellus, was assessed. A 4-wk exposure to the highest AgNP treatment reduced growth and reproduction compared with the control. Silver nitrate (AgNO3 ) exposure also impaired reproduction, but not as much as the highest AgNP treatment. Long-term exposure to the highest AgNP treatment caused complete juvenile mortality. All AgNP treatments induced tissue pathology. Population modeling demonstrated reduced population growth rates for the AgNP and AgNO3 treatments, and no population growth at the highest AgNP treatment because of juvenile mortality. Analysis of AgNP treated soil samples revealed that single AgNP and AgNP clusters were present in the soil, and that the total Ag in soil porewater remained high throughout the long-term experiment. In addition, immune cells (coelomocytes) of earthworms showed sensitivity to both AgNP and AgNO3 in vitro. Overall, the present study indicates that AgNP exposure may affect earthworm populations and that the exposure may be prolonged because of the release of a dissolved Ag fraction to soil porewater. PMID:24318461

van der Ploeg, Merel J C; Handy, Richard D; Waalewijn-Kool, Pauline L; van den Berg, Johannes H J; Herrera Rivera, Zahira E; Bovenschen, Jan; Molleman, Bastiaan; Baveco, Johannes M; Tromp, Peter; Peters, Ruud J B; Koopmans, Gerwin F; Rietjens, Ivonne M C M; van den Brink, Nico W

2014-04-01

57

Exotic earthworm invasion increases soil carbon and nitrogen in an old-growth forest in southern  

E-print Network

Exotic earthworm invasion increases soil carbon and nitrogen in an old-growth forest in southern Quebec M. Wironen and T.R. Moore Abstract: To test whether invasion of exotic earthworms affects soil varying in their earthworm populations in an old-growth beech­ maple forest at Mont St. Hilaire, southern

Moore, Tim

58

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

ERIC Educational Resources Information Center

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…

Davis, Kelly Cue; Logan-Greene, Patricia

2012-01-01

59

Testing the Deterrent Effects of Personal and Vicarious Experience with Punishment and Punishment Avoidance  

Microsoft Academic Search

Stafford and Warr (1993) reconceptualized general and specific deterrence into a single theory in which people's tendencies to commit crimes are based on a combination of personal experiences and vicarious experiences with being punished and avoiding punishment. The authors make a significant contribution to the deterrence literature by considering the effect of punishment avoidance when testing deterrence theory. The present

Alicia H. Sitren; Brandon K. Applegate

2007-01-01

60

Genotoxicity of two novel pesticides for the earthworm, Eisenia fetida  

Microsoft Academic Search

In this paper, several studies were conducted to evaluate the genotoxicity of two pesticides, Imidacloprid and RH-5849, for earthworm (Eisenia fetida). Earthworms were exposed in different exposure systems to evaluate their acute toxicity and the genotoxicity of the two pesticides was evaluated by using the method of sperm deformity assessment, micronucleus test of root tip cells in Vicia faba, a

Y. Zang; Y. Zhong; Y. Luo; Z. M. Kong

2000-01-01

61

Measuring and Improving Latency to Avoid Test Suite Wear Out Shin Yoo & Mark Harman  

E-print Network

Measuring and Improving Latency to Avoid Test Suite Wear Out Shin Yoo & Mark Harman King's College London Centre for Research on Evolution, Search & Testing (CREST) London, UK {shin.yoo, mark introduces the concept of test suite latency. The more latent a test suite, the more it is possible

Singer, Jeremy

62

Population dynamics of Pseudomonas corrugata 2140R lux8 in earthworm food and in earthworm casts  

Microsoft Academic Search

Earthworm food was tested as a carrier and inoculum source for Pseudomonas corrugata 2140R, a biocontrol agent for Take-all disease of wheat, in order to use the feeding, burrowing and casting activity of earthworms to disperse the biocontrol agent through soil. Three experiments are reported here using a bioluminescent derivative, P. corrugata 2140R lux8 (hereinafter called P. corrugata). In the

O. Schmidt; B. M. Doube; M. H. Ryder; K. Killham

1997-01-01

63

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

PubMed

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

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

2014-03-01

64

Nutrition Studies with Earthworms.  

ERIC Educational Resources Information Center

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)

Tobaga, Leandro

1980-01-01

65

Toxicity of diesel contaminated soils to the subantarctic earthworm Microscolex macquariensis.  

PubMed

Several fuel spills have occurred on subantarctic Macquarie Island (54°30' S 158°57' E) associated with storing fuel and generating power for the island's research station. The Australian Antarctic Division began full-scale, on-site remediation of these sites in 2009. To develop appropriate target concentrations for remediation, acute and chronic tests were developed with the endemic earthworm, Microscolex macquariensis, using avoidance, survival, and reproduction as endpoints. Uncontaminated low (3%), medium (11%), and high (38-48%) carbon content soils from Macquarie Island were used to examine the influence of soil carbon on toxicity. Soils were spiked with Special Antarctic Blend (SAB) diesel and used either immediately to simulate a fresh spill or after four weeks to simulate an aged spill. Earthworms were sensitive to fresh SAB, with significant avoidance at 181?mg/kg; acute 14-d survival median lethal concentration (LC50) of 103?mg/kg for low carbon soil; and juvenile production median effective concentration (EC50) of 317?mg/kg for high carbon soil. Earthworms were less sensitive to aged SAB than to fresh SAB in high carbon soil for juvenile production (EC50 of 1,753 and 317?mg/kg, respectively), but were more sensitive for adult survival (LC50 of 2,322 and 1,364?mg/kg, respectively). Using M. macquariensis as a surrogate for soil quality, approximately 50 to 200?mg SAB/kg soil would be a sufficiently protective remediation target. PMID:23147807

Mooney, Thomas J; King, Catherine K; Wasley, Jane; Andrew, Nigel R

2013-02-01

66

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

PubMed

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

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

2014-03-01

67

Flight Test Evaluation of a Prototype Optical Instrument for Airborne Sense-and-Avoid Applications  

E-print Network

the flight test performance of the "DragonflEYE" sensor as installed on a Bell 205 helicopter. Both the Bell ranges under the same conditions. Keywords: sense-and-avoid, safety, UAS, flight test, helicopter, SNR requirements5 for an SAA system are readily exceeded by readily available technology. Use of a camera system

Hornsey, Richard

68

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

PubMed

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

Ransom, Tami S

2011-03-01

69

Effect of earthworms on the biochemical characterization of biofilms in vermifiltration treatment of excess sludge.  

PubMed

In this study, the biofilms formed in a vermifilter (VF) with earthworms and a conventional biofilter (BF) without earthworms were compared to investigate the effects of earthworms on the characteristics of biofilms during an excess sludge treatment period of 4months. Typical macrographs and micrographs of the biofilms showed that the feeding and casting actions of earthworms remarkably modified the VF morphology. Elemental analysis and fluorescence spectra indicated that earthworms enhanced the stabilization of organic matter by accelerating the mineralization and humification of organic materials during vermiconversion. In addition, bacterial communities inhabiting the VF biofilm showed that earthworms increased both bacterial diversity and metabolic activities in the film, as revealed by automatic testing bacteriology (ATB) expression and sequencing data. These results demonstrate that earthworms influence the structure and biochemical characteristics of biofilms and enhance their bacterial diversity and functions for improved sludge stabilization. PMID:23774291

Yang, Jian; Liu, Jing; Xing, Meiyan; Lu, Zhibo; Yan, Qiong

2013-09-01

70

Avoidance test with Eisenia fetida as indicator for the habitat function of soils: Results of a laboratory comparison test  

Microsoft Academic Search

Intention, Goal, Scope, Background. The habitat function of soils is often assessed using the reproduction test withEisenia fetida. As this test is rather labour-intensive, an alternative is needed which is less cost-intensive in terms of duration and workload,\\u000a but gives reasonable results. The avoidance test withE. fetida is a suitable screening test meeting these criteria. However, before a novel test

Kerstin Hund-Rinke; Rudolf Achazi; Jörg Römbke; Dietmar Warnecke

2003-01-01

71

Movement response of Collembola to the excreta of two earthworm species: Importance of ammonium content and nitrogen forms  

Microsoft Academic Search

Several studies reported variable effects of earthworms on microarthropod density and variety. The present study tests the attraction of seven collembolan species belonging to four families, to the excreta of two earthworm species belonging to two families and two ecological categories, Aporrectodea giardi and Hormogaster elisae. Our objectives were (1) to better understand the impact of earthworms on the composition

Mónica Gutiérrez-López; Sandrine Salmon; Dolores Trigo

2011-01-01

72

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

NASA Technical Reports Server (NTRS)

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.

Skoog, Mark A.

2009-01-01

73

Comparative toxicity of chemicals to earthworms  

Microsoft Academic Search

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

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

1994-01-01

74

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

NASA Technical Reports Server (NTRS)

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.

Trongale, Nicholas A.

2006-01-01

75

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

PubMed

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

García-Santos, Glenda; Keller-Forrer, Karin

2011-07-01

76

Ceramide glycanase from the earthworm, Lumbricus terrestris.  

PubMed Central

Ceramide glycanase (CGase) is an enzyme that cleaves the linkage between the sugar chain and the ceramide. To make this enzyme readily available, we have developed a simple method for preparing it from the earthworm, Lumbricus terrestris. The method involves Bio-Gel A-0.5m, octyl-Sepharose and p-aminophenylthiogalactoside-agarose column chromatography. By gel filtration, the molecular mass of earthworm CGase was found to be 43.7 kDa. With ganglioside GM1 as substrate, the optimal pH of this enzyme was found to be between pH 3.5 and 4.0. Earthworm CGase hydrolyses glycolipids only in the presence of a detergent. Among various bile salts tested, sodium cholate was found to be the most effective in stimulating the hydrolysis of GM1 by this enzyme. Earthworm CGase released intact glycan chains from various glycosphingolipids in which the glycan chain is linked to the ceramide through a beta-glucosyl linkage. It also detached glycan chains from lactosyldialkylglycerol and alkyl-beta-lactosides. Images Fig. 1. Fig. 2. Fig. 3. PMID:1637351

Carter, B Z; Li, S C; Li, Y T

1992-01-01

77

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

Microsoft Academic Search

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

Colleen A. Dockery; Malgorzata J. Wesierska

2010-01-01

78

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

NASA Technical Reports Server (NTRS)

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.

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

1995-01-01

79

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

SciTech Connect

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.

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

1986-01-01

80

Science Sampler: Inquiry with earthworms  

NSDL National Science Digital Library

Earthworms wiggle their way into your science curriculum in this fun and hands-on activity. Students experiment with earthworms to gain a better understanding of the process of scientific inquiry and hone their research skills using books and the Internet (see Resources).

Jeanpierre, Bobby; Babyak, Joanne

2006-02-01

81

Toxicity of selected organic chemicals to the earthworm Eisenia fetida  

Microsoft Academic Search

A number of methods recently have been developed to biologically evaluate the impact of man's activities on soil ecosystems. Two test methods, the 2-d contact test and the 14-d artificial soil test, were used to evaluate the impact of six major classes of organic chemicals on the earthworm Eisenia fetida (Savigny). Of the organic chemicals tested, phenols and amines were

E. F. Neuhauser; R. C. Loehr; M. R. Malecki; D. L. Milligan; P. R. Durkin

2009-01-01

82

Acquiring data in real time in Italy from the Antarctic Seismographic Argentinean Italian Network (ASAIN): testing the global capabilities of the EarthWorm and Antelope software suites.  

NASA Astrophysics Data System (ADS)

The Italian National Institute for Oceanography and Experimental Geophysics (Istituto Nazionale di Oceanografia e di Geofisica Sperimentale, OGS) is running the Antarctic Seismographic Argentinean Italian Network (ASAIN), made of 7 seismic stations located in the Scotia Sea region in Antarctica and in Tierra del Fuego - Argentina: data from these stations are transferred in real time to the OGS headquarters in Trieste (Italy) via satellite links provided by the Instituto Antártico Argentino (IAA). Data is collected and archived primarily in Güralp Compress Format (GCF) through the Scream! software at OGS and IAA, and transmitted also in real time to the Observatories and Research Facilities for European Seismology (ORFEUS). The main real time seismic data acquisition and processing system of the ASAIN network is based on the EarthWorm 7.3 (Open Source) software suite installed on a Linux server at the OGS headquarters in Trieste. It runs several software modules for data collection, data archiving, data publication on dedicated web servers: wave_serverV, Winston Wave Server, and data analysis and realtime monitoring through Swarm program. OGS is also running, in close cooperation with the Friuli-Venezia Giulia Civil Defense, the North East (NI) Italy seismic network, making use of the Antelope commercial software suite from BRTT as the main acquisition system. As a test to check the global capabilities of the Antelope software suite, we also set up an instance of Antelope acquiring data in real time from both the regional ASAIN seismic network in Antarctica and a subset of the Global Seismic Network (GSN) funded by the Incorporated Research Institution for Seismology (IRIS). The facilities of the IRIS Data Management System, and specifically the IRIS Data Management Center, were used for real time access to waveform required in this study. The first tests indicated that more than 80% of the earthquakes with magnitude M>5.0 listed in the Preliminary Determination of Epicenters (PDE) catalogue of the National Earthquake Information Center (NEIC) of the United States Geological Survey (USGS) were also correctly automatically detected by Antelope, with an average location error of 0.05 degrees and average body wave magnitude Mb estimation error below 0.1. The average time difference between event origin time and the actual time of event determination by Antelope was of about 45': the comparison with 20', the IASPEI91 P-wave travel time for 180 degrees distance, and 25', the estimate of our test system data latency, indicate that Antelope is a serious candidate for regional and global early warning systems.

Percy Plasencia Linares, Milton; Russi, Marino; Pesaresi, Damiano; Cravos, Claudio

2010-05-01

83

Physiological and molecular responses of the earthworm (Eisenia fetida) to soil chlortetracycline contamination.  

PubMed

This study aims to evaluate toxic effects of exposure to chlortetracycline (CTC) in soil on reproductive endpoints (juvenile counts and cocoon counts), biochemical responses, and genotoxic potentials of the earthworm Eisenia fetida. Results showed that juvenile counts and cocoon counts of the tested earthworms were reduced after exposure to CTC. The effective concentrations (EC(50) values) for juvenile and cocoon counts were 96.1 and 120.3 mg/kg, respectively. Treatment of earthworms with CTC significantly changed the activity of catalase (CAT), superoxide dismutase (SOD) and glutathione S-transferase (GST). An increase in malondialdehyde (MDA) indicated that CTC could cause cellular lipid peroxidation in the tested earthworms. The percentage of DNA in the tail of single-cell gel electrophoresis of coelomocytes as an indication of DNA damage increased after treatment with different doses of CTC, and a dose-dependent DNA damage of coelomocytes was found. In conclusion, CTC induces physiological responses and genotoxicity on earthworms. PMID:22868346

Lin, Dasong; Zhou, Qixing; Xu, Yingming; Chen, Chun; Li, Ye

2012-12-01

84

Literature-derived bioaccumulation models for earthworms: Development and validation  

SciTech Connect

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.

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

1999-09-01

85

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

PubMed Central

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 (?), 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 ? 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

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

2014-01-01

86

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

PubMed

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 (?), 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 ? 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

Samia, Diogo S M; Blumstein, Daniel T

2014-01-01

87

Earthworm invasion into previously earthworm-free temperate and boreal forests  

Microsoft Academic Search

Earthworms are keystone detritivores that can influence primary producers by changing seedbed conditions, soil characteristics, flow of water, nutrients and carbon, and plant–herbivore interactions. The invasion of European earthworms into previously earthworm-free temperate and boreal forests of North America dominated by Acer, Quercus, Betula, Pinus and Populus has provided ample opportunity to observe how earthworms engineer ecosystems. Impacts vary with

Lee E. Frelich; Cindy M. Hale; Stefan Scheu; Andrew R. Holdsworth; Liam Heneghan; Patrick J. Bohlen; Peter B. Reich

2006-01-01

88

Influence of ultraviolet radiation on selected physiological responses of earthworms.  

PubMed

The purpose of this study was to investigate the adverse effects of ultraviolet (UV) radiation on earthworms. Earthworms that crawl out of the soil may die within a few hours after sunrise. This study shows that UV exposure can be lethal. In general, UV-B had a stronger damaging effect than UV-A. Different species of earthworms had different tolerances to UV exposure. In this study, Pontoscolex corethrurus showed the highest tolerance of the three tested species to UV radiation, while Amynthas gracilis was the most sensitive. UV radiation induced both acute and chronic responses. The acute response, which occurred immediately on or after UV exposure, was characterized by the appearance of abnormally strong muscle contractions, including S-shaped movements and jumping behavior, possibly caused by bad coordination between the circular and longitudinal muscles. The chronic response included damage to the skin and muscle cells, which resulted in a high mortality rate. Oxygen consumption by A. gracilis was significantly decreased after exposure to UV-A or UV-B. Since the circulation in earthworms is mediated by muscle contraction and the skin is the main organ of respiration, it is reasonable to expect that abnormal muscle contraction and a damaged epithelium could cause suffocation. Because of their sensitive responses, we propose that some earthworms, such as A. gracilis, could serve as a new model for studying UV-induced photodamage. PMID:17050845

Chuang, Shu-Chun; Lai, Wei-Shan; Chen, Jiun-Hong

2006-11-01

89

Avoidant romantic attachment and female orgasm: testing an emotion-regulation hypothesis  

Microsoft Academic Search

Recent research indicating that roughly a third of the variation in female orgasmic frequency is heritable leaves a substantial amount of non-heritable variation to be explained. Given that emotion regulation is central to attachment theory and that attachment insecurity in infancy and avoidance in adulthood are not heritable, it was predicted that (higher levels of) avoidance would predict (lower levels

Danielle L. Cohen; Jay Belsky

2008-01-01

90

For Better Soil, Let Earthworms Toil.  

ERIC Educational Resources Information Center

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)

Swinehart, Rebecca, Ed.

1995-01-01

91

Comparative Toxicity in Earthworms Eisenia fetida and Lumbricus terrestris Exposed to Cadmium Nitrate Using Artificial Soil and Filter Paper Protocols  

Microsoft Academic Search

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

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

1996-01-01

92

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

Microsoft Academic Search

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.

John R. Meier; Lina W. Chang; M. C. Meckes; M. K. Smith; S. Jacobs; J. Torsella

1997-01-01

93

Effects of earthworms on nitrogen mineralization  

Microsoft Academic Search

The influence of earthworms (Lumbricus terrestris and Aporrectodea tuberculata) on the rate of net N mineralization was studied, both in soil columns with intact soil structure (partly influenced by past earthworm activity) and in columns with sieved soil. Soil columns were collected from a well drained silt loam soil, and before the experiment all earthworms present were removed. Next, either

J. J. G. M. Willems; J. C. Y. Marinissen; J. Blair

1996-01-01

94

Organic carbon sequestration in earthworm burrows  

Microsoft Academic Search

Earthworms strongly affect soil organic carbon cycling. The aim of this study was to determine whether deep burrowing anecic earthworms enhance carbon storage in soils and decrease C turnover. Earthworm burrow linings were separated into thin cylindrical sections with different distances from the burrow wall to determine gradients from the burrow wall to the surrounding soil. Organic C, total N,

Axel Don; Bert Steinberg; Ingo Schöning; Karin Pritsch; Monika Joschko; Gerd Gleixner; Ernst-Detlef Schulze

2008-01-01

95

Use of an avoidance test for the assessment of microbial degradation of PAHs1 Christine Lors1  

E-print Network

1 Use of an avoidance test for the assessment of microbial degradation of PAHs1 2 Christine Lors1 (50%). PAH disappearance was linked to10 the occurrence of indigenous microbiota able to degrade springtail Folsomia candida was used to assess3 changes in contamination levels at low doses of PAHs

Paris-Sud XI, Université de

96

The effects of earthworms on the demography of annual plant assemblages in a long-term mesocosm experiment  

Microsoft Academic Search

Earthworms have been shown to influence plant growth, survival and fecundity. They can therefore affect plant demography in plant communities changing their composition. A long term mesocosm experiment was set-up to test the effects of an endogeic (Aporrectodea caliginosa) and an anecic (Lumbricus terrestris) earthworm species on assemblages of four species of annuals: one grass (Poa annua), two forbs (Veronica

Kam-Rigne Laossi; Diana Cristina Noguera; Thibaud Decäens; Sébastien Barot

2011-01-01

97

Avoidance of low pH and elevated Al concentrations by Brook Charr ( Salvelinus fontinalis ) Alevins in laboratory tests  

Microsoft Academic Search

Laboratory studies were conducted to test the ability of brook charr (Salvelinus fontinalis) alevins, the earliest free-swimming life stage of the species, to detect and avoid toxic levels of H+ and inorganic Al. Alevins were tested in steep gradient choice tanks using a range of H+ (pH 4.0 to 5.5) and Al (0 to 500 µg L-1) concentrations in low

John M. Gunn; David L. G. Noakes

1986-01-01

98

Protein Hydrolysates Are Avoided by Herbivores but Not by Omnivores in Two-Choice Preference Tests  

Microsoft Academic Search

Background: The negative sensory properties of casein hydrolysates (HC) often limit their usage in products intended for human consumption, despite HC being nutritious and having many functional benefits. Recent, but taxonomically limited, evidence suggests that other animals also avoid consuming HC when alternatives exist. Methodology\\/Principal Findings: We evaluated ingestive responses of five herbivorous species (guinea pig, mountain beaver, gopher, vole,

Kristin L. Field; Alexander A. Bachmanov; Julie A. Mennella; Gary K. Beauchamp; Bruce A. Kimball

2009-01-01

99

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

PubMed Central

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

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

2011-01-01

100

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

PubMed Central

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

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

2014-01-01

101

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

PubMed

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

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

2014-01-01

102

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

NASA Technical Reports Server (NTRS)

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

Halley, J. W.; Nakanishi, H.

1985-01-01

103

Protein Hydrolysates Are Avoided by Herbivores but Not by Omnivores in Two-Choice Preference Tests  

Microsoft Academic Search

BackgroundThe negative sensory properties of casein hydrolysates (HC) often limit their usage in products intended for human consumption, despite HC being nutritious and having many functional benefits. Recent, but taxonomically limited, evidence suggests that other animals also avoid consuming HC when alternatives exist.Methodology\\/Principal FindingsWe evaluated ingestive responses of five herbivorous species (guinea pig, mountain beaver, gopher, vole, and rabbit) and

Kristin L. Field; Alexander A. Bachmanov; Julie A. Mennella; Gary K. Beauchamp; Bruce A. Kimball; Daniel Tomé

2009-01-01

104

Earthworm invasion into previously earthworm-free temperate and boreal forests  

Microsoft Academic Search

Earthworms are keystone detritivores that can influence primary producers by changing seedbed conditions, soil characteristics,\\u000a flow of water, nutrients and carbon, and plant-herbivore interactions. The invasion of European earthworms into previously\\u000a earthworm-free temperate and boreal forests of North America dominated by Acer, Quercus, Betula, Pinus and Populus has provided ample opportunity to observe how earthworms engineer ecosystems. Impacts vary with

Lee E. Frelich; Cindy M. Hale; Peter B. Reich; Andrew R. Holdsworth; Stefan Scheu; Liam Heneghan; Patrick J. Bohlen

105

Evolution of earthworm burrow systems after inoculation of lumbricid earthworms in a pasture in the Netherlands  

Microsoft Academic Search

In 1983, an earthworm-free pasture was inoculated with four earthworm species. The earth-worms dispersed with an average velocity of 6.3 m y?1. In 1991, four burrow systems, ranging in age from 0.6 to 7.3 y, were mapped three-dimensionally to establish the development of these systems. Aporrectodea longa was the fastest colonizer, while Lumbricus terrestris dispersed slowly. The abundance of earthworms

Tom N. Ligthart; Gert J. C. W. Peek

1997-01-01

106

INTERACTIONS BETWEEN PLANT SPECIES AND EARTHWORM CASTS IN A CALCAREOUS GRASSLAND UNDER ELEVATED CO 2  

Microsoft Academic Search

We 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 at- mospheric CO2. In 1995 we mapped the location of both earthworm surface casts and plants in each of 16 1.2-m2 plots

Johann G. Zaller; John A. Arnone

1999-01-01

107

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

Microsoft Academic Search

Silver nanoparticles have been incorporated into a wide variety of consumer products, ideally acting as antimicrobial agents.\\u000a Silver exposure has long been known to cause toxic effects to a wide variety of organisms, making large scale production of\\u000a silver nanoparticles a potential hazard to environmental systems. Here we describe the first evidence that an organism may\\u000a be able to sense

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

2011-01-01

108

Earthworms as seedling predators: Importance of seeds and seedlings for earthworm nutrition  

Microsoft Academic Search

Anecic earthworms have been shown to collect, concentrate and bury seeds in their burrows. Moreover, recent studies suggest that earthworms function as granivores and seedling herbivores thereby directly impacting plant community assembly. However, this has not been proven unequivocally. Further, it remains unclear if earthworms benefit from seed ingestion, i.e., if they assimilate seed carbon. We set up a series

Nico Eisenhauer; Olaf Butenschoen; Stefan Radsick; Stefan Scheu

2010-01-01

109

The Earthworm Inoculation Unit technique: An integrated system for cultivation and soil-inoculation of earthworms  

Microsoft Academic Search

The introduction of earthworms into degraded or newly restored land is known to promote soil improvement. Obtaining the most appropriate species in the large numbers required can be costly and time consuming using traditional techniques. Research and development of a novel approach, the Earthworm Inoculation Unit (EIU) technique, may help to overcome this. This technique combines cultivation of selected earthworms

Kevin R. Butt; James Frederickson; Richard M. Morris

1997-01-01

110

Interference of Plant Peroxidases with Guaiac based Fecal Occult Blood Tests Is Avoidable  

Microsoft Academic Search

Peroxidase-rich fruits and vegetables are reputed to interfere with guaiac-based fecal occult blood tests. We added horseradish peroxidase to fecal samples and tested them with Hemoccult®, Hemoccult SENSA®, and hydrated Hemoccult. Positivity rates with Hemoccult and Hemoccult SENSA decreased rapidly as the time between smearing (preparation) and development in- creased, whereas they remained high with hydrated Hemoccult. For samples with

Marc A. Sinatra; D. James; Graeme P. Young

111

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

NASA Astrophysics Data System (ADS)

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

Guttmann, Anthony J.; Jacobsen, Jesper L.

2013-11-01

112

Affective and cognitive attitudes, uncertainty avoidance and intention to obtain genetic testing: an extension of the Theory of Planned Behaviour.  

PubMed

To ensure successful implementation of genetic screening and counselling according to patients best interests, the attitudes and motives of the public are important to consider. The aim of this study was to apply a theoretical framework in order to investigate which individual and disease characteristics might facilitate the uptake of genetic testing. A questionnaire using an extended version of the Theory of Planned Behaviour was developed to assess the predictive value of affective and cognitive expected outcomes, subjective norms, perceived control and uncertainty avoidance on the intention to undergo genetic testing. In addition to these individual characteristics, the predictive power of two disease characteristics was investigated by systematically varying the diseases fatality and penetrance (i.e. the probability of getting ill in case one is a mutation carrier). This resulted in four versions of the questionnaire which was mailed to a random sample of 2400 Norwegians. Results showed genetic test interest to be quite high, and to vary depending on the characteristics of the disease, with participants preferring tests for highly penetrant diseases. The most important individual predictor was uncertainty avoidance. PMID:21347976

Wolff, Katharina; Nordin, Karin; Brun, Wibecke; Berglund, Gunilla; Kvale, Gerd

2011-09-01

113

Avoiding the {open_quotes}definition{close_quotes} pitfall to a comprehensive test ban  

SciTech Connect

Recently approved US legislation and a new US administration have brought an end to 12 years of American opposition to a comprehensive test ban (CTB). Signed by President Bush on October 2, 1992, the new law imposes a moratorium on US nuclear tests until July and possibly longer, permits up to 15 nuclear tests to improve the safety and reliability of nuclear weapons from the end of this moratorium until October 1996, and prohibits US tests after that unless another country tests. It also calls on the president to submit a plan for resumption of negotiations to end testing. President Bill Clinton, in his February 12, 1993 letter to Senate Majority Leader George Mitchell (D-ME) supporting this legislation, said his administration was now reviewing questions {open_quotes}of forum and modalities for negotiating a CTB...{close_quotes} Moreover, Presidents Clinton and Boris Yeltsin, at their April summit in Vancouver, {open_quotes}agreed that negotiations on a multilateral nuclear test ban should commence at an early date.{close_quotes}

Bunn, G.; Timerbaev, R.

1993-05-01

114

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

ERIC Educational Resources Information Center

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

Frey, Allan H.; Frey, Donnalyn

1979-01-01

115

Acute toxicity of chlorophenols to earthworms using a simple paper contact method and comparison with toxicities to fresh water organisms  

Microsoft Academic Search

An acute toxicity test of chlorophenols on earthworms (Eisenia fetida) was performed using a simple paper contact method proposed by OECD testing guideline no. 207, that were applied as an earthworm toxicity test. The median lethal concentration, EC50, had significant correlation with logPow (1-octanol\\/water partition coefficient) of the chemicals. The toxicity of chlorophenols on E. fetida was compared with toxicities

Akane Miyazaki; Tsutomu Amano; Hotaka Saito; Yoshio Nakano

2002-01-01

116

Predatory beetles facilitate plant growth by driving earthworms to lower soil layers.  

PubMed

Theory suggests that predators of soil-improving, plant-facilitating detritivores (e.g. earthworms) should suppress plant growth via a negative tri-trophic cascade, but the empirical evidence is still largely lacking. We tested this prediction in an alpine meadow on the Tibetan Plateau by manipulating predatory beetles (presence/absence) and quantifying (i) direct effects on the density and behaviour of earthworms; and (ii) indirect effects on soil properties and above-ground plant biomass. In the absence of predators, earthworms improved soil properties, but did not significantly affect plant biomass. Surprisingly, the presence of predators strengthened the positive effect of earthworms on soil properties leading to the emergence of a positive indirect effect of predators on plant biomass. We attribute this counterintuitive result to: (i) the inability of predators to suppress overall earthworm density; and (ii) the predator-induced earthworm habitat shift from the upper to lower soil layer that enhanced their soil-modifying, plant-facilitating, effects. Our results reveal that plant-level consequences of predators as transmitted through detritivores can hinge on behaviour-mediated indirect interactions that have the potential to overturn predictions based solely on trophic interactions. This work calls for a closer examination of the effects of predators in detritus food webs and the development of spatially explicit theory capable of predicting the occurrence and consequences of predator-induced detritivore behavioural shifts. PMID:23419174

Zhao, Chuan; Griffin, John N; Wu, Xinwei; Sun, Shucun

2013-07-01

117

Fat but slim: Criteria of seed attractiveness for earthworms  

Microsoft Academic Search

Earthworms were shown to significantly affect seeds and seedlings survival via their ingestion and digestion for nutritive purposes. Such selective feeding of earthworms on plant seeds is likely to favour certain plant species and to affect seed bank composition, plant recruitment and plant community structure. Relationships between earthworms and seeds, particularly seed traits that determine attractiveness of seeds for earthworms,

Julia Clause; Pierre Margerie; Estelle Langlois; Thibaud Decaëns; Estelle Forey

118

ORIGINAL PAPER Tree rings detect earthworm invasions and their effects  

E-print Network

ORIGINAL PAPER Tree rings detect earthworm invasions and their effects in northern Hardwood forests of European earthworms into the forests of northern North America are causing dramatic changes in forest floor on the effects of invasive earthworms are limited because little data exist on the timing and rate of earthworm

Minnesota, University of

119

How do earthworms affect microfloral and faunal community diversity?  

Microsoft Academic Search

Much of the work regarding earthworm effects on other organisms has focused on the functional significance of microbial-earthworm interactions, and little is known on the effects of earthworms on microfloral and faunal diversity. Earthworms can affect soil microflora and fauna populations directly and indirectly by three main mechanisms: (1) comminution, burrowing and casting; (2) grazing; (3) dispersal. These activities change

George G. Brown

1995-01-01

120

Earthworm activities and the soil system  

Microsoft Academic Search

Earthworms find in soil the energy, nutrient resources, water and buffered climatic conditions that they need. According to the food resource they exploit and the general environmental conditions, earthworms can be grouped into different functional categories which differ essentially in morphology, size, pigmentation, distribution in the soil profile, ability to dig galleries and produce surface casts, demographic profiles and relationships

P. Lavelle

1988-01-01

121

Colonization of new habitats by earthworms  

Microsoft Academic Search

In this paper a simple model is used to study the dispersal of earthworm populations into new habitats. Simple models do not describe processes accurately, but can help gain insight into the functioning of ecosystems or processes in ecosystems. Using information on reproduction, survival and dispersal at the level of the individual, the velocity of earthworm population expansion was calculated.

J. C. Y. Marinissen; Bosch van den F

1992-01-01

122

Significance of earthworms in stimulating soil microbial activity  

Microsoft Academic Search

The stimulatory effect of earthworms (Lumbricus terrestris L.) on soil microbial activity was studied under microcosm-controlled conditions. The hypothesis was tested that microbial\\u000a stimulation observed in the presence of a soil invertebrate would be due to the utilization of additional nutritive substances\\u000a (secretion and excretion products) that it provides. Changes in microbial activity were monitored by measuring simultaneously\\u000a CO2 release

F. Binet; L. Fayolle; M. Pussard; J. J. Crawford; S. J. Traina; O. H. Tuovinen

1998-01-01

123

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)

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.

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

2013-01-01

124

Improving ecological risk assessment in the Mediterranean area: selection of reference soils and evaluating the influence of soil properties on avoidance and reproduction of two oligochaete species.  

PubMed

A current challenge in soil ecotoxicology is the use of natural soils as test substrates to increase ecological relevance of data. Despite the existence of six natural reference soils (the Euro-soils), some parallel projects showed that these soils do not accurately represent the diversity of European soils. Particularly, Mediterranean soils are not properly represented. To fill this gap, 12 natural soils from the Mediterranean regions of Alentejo, Portugal; Cataluña, Spain; and Liguria, Italy, were selected and used in reproduction and avoidance tests to evaluate the soil habitat function for earthworms (Eisenia andrei) and enchytraeids (Enchytraeus crypticus). Predictive models on the influence of soil properties on the responses of these organisms were developed using generalized linear models. Results indicate that the selected soils can impact reproduction and avoidance behavior of both Oligochaete species. Reproduction of enchytraeids was affected by different soil properties, but the test validity criteria were fulfilled. The avoidance response of enchytraeids was highly variable, but significant effects of texture and pH were found. Earthworms were more sensitive to soil properties. They did not reproduce successfully in three of the 10 soils, and a positive influence of moisture, fine sand, pH, and organic matter and a negative influence of clay were found. Moreover, they strongly avoided soils with extreme textures. Despite these limitations, most of the selected soils are suitable substrates for ecotoxicological evaluations. PMID:21305581

Chelinho, Sónia; Domene, Xavier; Campana, Paolo; Natal-da-Luz, Tiago; Scheffczyk, Adam; Römbke, Jörg; Andrés, Pilar; Sousa, José Paulo

2011-05-01

125

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

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.

Baldigo, B.P.; Baudanza, T.P.

2001-01-01

126

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

PubMed Central

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

2014-01-01

127

Comparative toxicity of chemicals to earthworms  

SciTech Connect

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.

Callahan, C.A.; Shirazi, M.A. (Environmental Protection Agency, Corvallis, OR (United States)); Neuhauser, E.F. (Niagara Mohawk Power Corp., Syracuse, NY (United States))

1994-02-01

128

1 H NMR and GC\\/MS metabolomics of earthworm responses to sub-lethal DDT and endosulfan exposure  

Microsoft Academic Search

The metabolic response of the earthworm Eisenia fetida to two pesticides, dichlorodiphenyltrichloroethane (DDT) and endosulfan, was characterized in contact tests using proton\\u000a nuclear magnetic resonance (1H NMR) and principal component analysis (PCA). PCA loading plots suggested that maltose, leucine and alanine were important\\u000a metabolites contributing to the differences in dosed and control earthworms for both compounds at doses of 0.5,

Jennifer R. McKelvie; Jimmy Yuk; Yunping Xu; Andre J. Simpson; Myrna J. Simpson

2009-01-01

129

Effect of earthworm on growth of late succession plant species in postmining sites under laboratory and field conditions  

Microsoft Academic Search

Earlier studies of postmining heaps near Sokolov, Czech Republic (0–46 years old) showed that massive changes in plant community\\u000a composition occur around 23 year of succession when the heaps are colonized by the earthworms Lumbricus rubellus (Hoffm.) and Aporrectodea caliginosa (Savigny). The aim of the current study was to test the hypothesis that the introduction of earthworms into a postmining\\u000a soil enhances

Alena Roubí?ková; Ond?ej Mudrák; Jan Frouz

2009-01-01

130

Contribution of earthworms to PCB bioremediation  

Microsoft Academic Search

Twenty cm deep columns containing Aroclor 1242 contaminated soil were bioaugmented with the PCB-degrading micro-organisms, Ralstonia eutrophus H850 and Rhodococcus sp. strain ACS, each of which were grown on sorbitan trioleate, and induced for PCB degradation by salicylic acid and carvone, respectively. Treatments consisted of soils with and without earthworms. Earthworms were utilized to enhance the dispersal of the bioaugmented

A. C Singer; W Jury; E Luepromchai; C.-S Yahng; D. E Crowley

2001-01-01

131

Alarm pheromone in the earthworm Lumbricus terrestris.  

PubMed

Noxious stimulation of the earthworm Lumbricus terrestris elicits secretion of a mucus that is aversive to other members of the species, as well as to the stimulated animal when it is encountered later. This alarm pheromone is not readily soluble in water and retains its aversive properties for at least several months if not disturbed. Its influence may be responsible for some features of the data on instrumental learning in earthworms. PMID:5663305

Ressler, R H; Cialdini, R B; Ghoca, M L; Kleist, S M

1968-08-01

132

Odor-avoidance or odor-preference induced by amphetamine in the infant rat depending on the dose and testing modality.  

PubMed

By the second postnatal week of life infant rats can acquire taste avoidance induced by amphetamine. Psychostimulant drugs supports appetitive and aversive learning in adult rats. Their appetitive effects are more likely to become associated with contextual cues, while the aversive ones have been consistently found in taste aversion learning. To explain this paradox, it has been proposed that rats would avoid a taste that predicts a change in their homeostasis because this species cannot vomit. In this study we assessed the motivational properties of amphetamine in preweanling rats by means of an odor conditioning preparation, which enables the analysis of the hedonic value of the memory by means of a consumption test or in terms of locomotor approach to the odor. Results indicate that regardless of the amphetamine dose (1 or 5 mg/kg), when animals were evaluated in the intake test, subjects avoided the odor. However, the outcome in the locomotor avoidance test varied as a function of the amphetamine dose. Rats trained with the low dose (1 mg/kg) showed odor preference, while the highest amphetamine dose (5 mg/kg) induced odor avoidance. When LiCl was employed as an unconditioned stimulus (US), rats showed avoidance in the intake and locomotor activity tests. These data indicate that amphetamine, like other drugs of abuse, supports appetitive conditioning in preweanling rats. Interestingly, infant rats expressed conditioned odor avoidance or preference depending on the dose and testing modality. Results were discussed considering current theories of avoidance learning induced by rewarding drugs. PMID:22465170

Revillo, Damian A; Fernandez, Guillermo; Castello, Stefania; Paglini, Maria Gabriela; Arias, Carlos

2012-05-16

133

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

PubMed

(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

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

2013-11-01

134

Impact of landspread sewage sludge and earthworm introduction on established earthworms and soil structure  

Microsoft Academic Search

Sewage sludge was applied to twelve 4-m2 plots in two forest (mixed hardwood, Norway spruce plantation) site and one old field site. The earthworm Eisenia fetida was introduced to half the control and half the treated plots. Earthworm populations were sampled by formalin extraction and hand-sorting five times in the year following treatment. One year after treatment, soil samples were

W. E. Hamilton; D. L. Dindal

1989-01-01

135

Earthworm-mediated maternal effects on seed germination and seedling growth in three annual plants  

Microsoft Academic Search

Many ecological studies have pointed out maternal effects in plants and shown that plant maternal environment influences germination of their seed and subsequent seedling growth. However, few have tested for maternal effects induced by soil macroorganisms. We tested whether two earthworm species (Aporrectodea caliginosa and Lumbricus terrestris) trigger such maternal effects on seed germination and seedling growth of three plant

Kam-Rigne Laossi; Diana-Cristina Noguera; Sébastien Barot

2010-01-01

136

Comparison of Three Earthworm Bioassay Procedures for the Assessment of Environmental Samples Containing Hazardous Wastes.  

National Technical Information Service (NTIS)

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-d...

C. A. Callahan, L. K. Russell, S. A. Peterson

1985-01-01

137

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

PubMed

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

Tiunov, A V; Kuznetsova, N A

2000-01-01

138

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

NASA Astrophysics Data System (ADS)

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.

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

2013-12-01

139

Bioconversion of solid paper-pulp mill sludge by earthworms  

Microsoft Academic Search

Bioconversion of solid paper-pulp mill sludges and primary sewage sludge for 40 days at a ratio of 3:1 dw:dw was studied in containers with and without earthworms (Eisenia andrei). This mixture was a suitable medium for optimum growth and reproduction of the earthworms. Regardless of the presence of earthworms, degradation occurred during the bioconversion period, but the presence of earthworms

C. Elvira; M. Goicoechea; L. Sampedro; S. Mato; R. Nogales

1996-01-01

140

Distribution and impacts of invasive earthworms in Canadian forest ecosystems  

Microsoft Academic Search

In Canada it is generally accepted that most indigenous earthworms did not survive glaciation, and that the majority of the\\u000a earthworms now inhabiting Canadian soils are relatively recent introductions of European origin. Although these exotic earthworms\\u000a are generally considered to be beneficial in agricultural soils, their effects can be less benign in forested ecosystems.\\u000a Studies have shown that invading earthworms

J. A. Addison

141

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

Microsoft Academic Search

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%

Dael E. Morris; Kenneth A. Pivnick

1991-01-01

142

A viable technique for tagging earthworms using visible implant elastomer  

Microsoft Academic Search

Earthworms perform many ecosystem services. However, due to their body shape, mucus covering, and subterranean behaviour, it has been very difficult to successfully tag individual animals for experimental purposes. This paper examines the potential use of commercially available visible implant elastomer (VIE) tags to mark earthworms. Two laboratory experiments were conducted employing four temperate earthworm species by injection of the

Kevin R. Butt; Christopher N. Lowe

2007-01-01

143

Different earthworm ecological groups interactively impact seedling establishment  

Microsoft Academic Search

There is increasing evidence that direct interactions between earthworms and seeds impact the assembly of plant communities. However, effects of earthworms of different ecological groups and their interactions on plant germination and establishment are little known. We set up a full-factorial greenhouse experiment in order to explore impacts of different ecological groups of earthworms (epigeic, endogeic and anecic) on the

Roman Asshoff; Stefan Scheu; Nico Eisenhauer

2010-01-01

144

ORIGINAL PAPER Resident plant diversity and introduced earthworms have  

E-print Network

ORIGINAL PAPER Resident plant diversity and introduced earthworms have contrasting effects such as earthworms can also affect invasibility by reducing leaf litter stocks and influencing soil conditions. In a greenhouse experiment, we simulta- neously manipulated resident species diversity and earthworm presence

Minnesota, University of

145

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

ERIC Educational Resources Information Center

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)

McLaughlin, Molly

1994-01-01

146

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

NASA Astrophysics Data System (ADS)

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.

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

2014-03-01

147

The combined stress effects of salinity and copper on the earthworm Eisenia fetida  

Microsoft Academic Search

Most studies on the effects of salinity or copper on soil organisms have hitherto focused on testing of individual substance toxicity which cannot adequately predict the toxicity of mixtures of contaminants due to their possible interaction in soil or at the point of entry into organisms. In order to assess the joint toxic effect of salinity and Cu to earthworms,

Olugbenga J. Owojori; Adriaan J. Reinecke; Andrei B. Rozanov

2009-01-01

148

Assessing the Impact of Triazine Herbicides on Organophosphate Insecticide Toxicity to the Earthworm Eisenia fetida  

Microsoft Academic Search

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

M. J. Lydy; S. L. Linck

2003-01-01

149

Assessing effects of transgenic Cry1Ac cotton on the earthworm Eisenia fetida  

Microsoft Academic Search

Transgenic insect-resistant cotton containing a synthetic version of the insecticidal toxin gene from Bacillus thuringiensis subsp. kurstaki has been planted in China in a large scale and may have adverse impacts on soil organisms. The leaves of the transgenic cotton and the non-transgenic parental cotton were collected and their impacts on the earthworm, Eisenia fetida, were tested in laboratory studies.

Biao Liu; Liang Wang; Qing Zeng; Jun Meng; Wenjun Hu; Xiaogang Li; Kexin Zhou; Kun Xue; Doudou Liu; Yangping Zheng

2009-01-01

150

The role of earthworms ( Eisenia fetida ) in influencing bioavailability of heavy metals in soils  

Microsoft Academic Search

The effects of earthworm ( Eisenia fetida) activity on soil pH, dissolved organic carbon (DOC), microbial populations, fraction distribution and bioavailability of heavy metals (Zn, Cu, Cr, Cd, Co, Ni, and Pb) in five Chinese soils were investigated using pot experiments. A three-step extraction procedure recommended by the European Community Bureau of Reference (BCR; now Standards, Measurements and Testing Programme

Bei Wen; Xiao-yu Hu; Ying Liu; Wei-sheng Wang; Mu-hua Feng; Xiao-quan Shan

2004-01-01

151

Shade avoidance.  

PubMed

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

Casal, Jorge J

2012-01-01

152

Shade Avoidance  

PubMed Central

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

Casal, Jorge J.

2012-01-01

153

Influence of Exotic Earthworms on the Soil Organic Horizon and the Rare Fern Botrychium mormo  

Microsoft Academic Search

Forests north of the last glacial extent have no native earthworms. Exotic earthworms are now col- onizing forests that are naturally free of earthworms. It is currently unknown how these exotic earthworms might affect rare plants. To determine whether there is an association between the presence of an exotic earthworm species and extirpation of the rare fern Botrychium mormo ,

Michael J. Gundale

2002-01-01

154

Dehydration does not affect the radial pressures produced by the earthworm Aporrectodea caliginosa  

Microsoft Academic Search

As a soil dries, the earthworms in that soil dehydrate and become less active. Moisture stress may weaken an earthworm, lowering the radial pressure that the animal can produce. This possibility was investigated for the earthworm Aporrectodea caliginosa (Savigny). Pressures were compared for saturated earthworms (worms taken from saturated soil) and stressed earthworms (worms that had been partially dehydrated by

Robert J. Stovold; W. Richard Whalley; Peter J. Harris

2003-01-01

155

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

SciTech Connect

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.

Gibbs, M.H. [Univ. of Tennessee, Knoxville, TN (United States); Wicker, L.F.; Stewart, A.J. [Oak Ridge National Lab., TN (United States)

1994-12-31

156

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

SciTech Connect

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.

Holmstrup, M. [National Environmental Research Inst., Silkeborg (Denmark). Dept. of Terrestrial Ecology; Petersen, B.F. [National Environmental Research Inst., Silkeborg (Denmark). Dept. of Terrestrial Ecology]|[Univ. of Aarhus (Denmark); Larsen, M.M. [National Environmental Research Inst., Roskilde (Denmark). Dept. of Marine Ecology and Microbiology

1998-01-01

157

Earthworm-induced N mineralization in fertilized grassland increases N2O emission more than crop N uptake  

NASA Astrophysics Data System (ADS)

Earthworms are known to be important regulators of major soil processes and functions such as structure, organic matter (OM) decomposition, nutrient cycling, microbial composition and activity, and plant production. For instance, they have been reported to increase plant nitrogen (N) availability through increasing mineralization of organic matter. Recent studies have indicated that earthworms can also lead to elevated emissions of the potent greenhouse gas nitrous oxide (N2O) during crop residue decomposition. It is unclear to what extend these two effects interplay in fertilized grasslands, where earthworm densities are typically highest and N and C inputs are high and continuous. The objectives of this study were therefore to (i) quantify earthworm-induced N uptake and N2O emissions in fertilized grasslands, and (ii) to link these effects to earthworm functional groups. In a factorial lysimeter experiment, we introduced combinations of earthworm species in soil columns with growing grass on a loamy soil during a 73 day incubation period. Main effects as well as all 2- and 3-way interactions were tested for individuals that represented the three ecological earthworm strategies: Lumbricus rubellus [R] (epigeic), Apporectodea longa [L] (anecic), and Apporectodea caliginosa [C] (endogeic). Lysimeters were placed outside and the total amount of fertilizer applied during the incubation period amounted to 250 kg N ha-1. R increased grass biomass with 5.4 % (p=0.032) and grass N uptake from 171.5 to 187.6 kg N ha-1 (p<0.001). C increased grass N uptake from 176.0 to 183.0 kg N ha-1 (p=0.001), and the combination of the three earthworm species together increased N uptake by 18.5% (p=0.006). Soil with R had higher concentrations of NH4+ (p=0.010), further indicating increased mineralization of N due to earthworm activity. Cumulative N2O emissions ranged from 197 ?g N2O-N kg-1 soil in the presence of L to 312 ?g N2O-N kg-1 soil in the presence of R. R increased N2O emissions with 50.8% (p<0.001). In conclusion, these results indicate that the beneficial effect of earthworm presence on plant N availability comes with a negative side-effect: increased emissions of mineral N in the form of N2O.

Lubbers, I. M.; Brussaard, L.; van Groenigen, J.

2009-12-01

158

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

SciTech Connect

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.

Fitzpatrick, L.C.; Goven, A.J. [Univ. of North Texas, Denton, TX (United States)] [Univ. of North Texas, Denton, TX (United States); Muratti-Ortiz, J.F. [City of Denton Water/Wastewater Laboratory, TX (United States)] [City of Denton Water/Wastewater Laboratory, TX (United States); Venables, B.J. [TRAC Laboratories Inc., Denton, TX (United States)] [TRAC Laboratories Inc., Denton, TX (United States)

1996-07-01

159

United States Department of Native and Introduced Earthworms fromAgriculture  

E-print Network

of various southern California wildland habitats. The ecology and biology of earthworms are outlinedUnited States Department of Native and Introduced Earthworms fromAgriculture Forest Service. 1993. Native and introduced earthworms from selected chaparral, woodland, and riparian zones

Standiford, Richard B.

160

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...

161

Estimating Earthworm Populations by Using Formalin  

Microsoft Academic Search

WHILE investigating the removal of leaves by earthworms from the soil surface of some apple orchards at Wisbech (Cambs.) an estimate of the population of Lumbricus terrestris was needed because it seemed to be the only species present that pulled apple leaves into its burrows. L. terrestris burrows deeply in the light, well-drained soil of the Wisbech area, and a

F. Raw

1959-01-01

162

Reproductive potential of the earthworm Eisenia foetida  

Microsoft Academic Search

Regression equations are provided for the earthworm Eisenia foetida with respect to age at which 50% of the population became clitellate at 25° C in relation to population density in activated sludge and in horse manure. Regression equations are provided for progeny per cocoon versus weight of cocoon, and weight of cocoon in relation to weight of parent; from these

Roy Hartenstein; Edward F. Neuhauser; David L. Kaplan

1979-01-01

163

Easy Extraction of Roundworms from Earthworm Hosts.  

ERIC Educational Resources Information Center

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…

Eyster, Linda S.; Fried, Bernard

2000-01-01

164

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

PubMed Central

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.

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

2014-01-01

165

Can commonly measurable traits explain differences in metal accumulation and toxicity in earthworm species?  

PubMed

There is no clear consensus in the literature on the metal accumulation pattern and sensitivity of different earthworm species. In the present study, accumulation and toxicity of Cu, Cd, Ni, and Zn in the earthworms Lumbricus rubellus (epigeic), Aporrectodea longa (anecic), and Eisenia fetida (ultra-epigeic) were determined after 28 days exposure in two soils. Metal accumulation and sensitivity were interpreted using the specific traits of different earthworm species. Results showed that for all four metals tested L. rubellus was the most sensitive species, followed by A. longa and E. fetida. At the same exposure concentration, internal concentrations followed the order: L. rubellus > E. fetida > A. longa for Cu and Ni, L. rubellus ? E. fetida ? A. longa for Cd, and L. rubellus > A. longa > E. fetida for Zn. Langmuir isotherms were used to model metal accumulation at both nontoxic and toxic exposure concentrations. The Cu, Cd, and Zn concentrations in E. fetida generally leveled off at high exposure concentrations but not for the other two species. A. longa showed a high capability of regulating internal Ni concentrations. The traits-based approaches suggested that most likely a group of earthworm traits together determined (differences in) metal accumulation and sensitivity. More research is needed in this respect to build up solid relationships between species-specific responses and traits, enabling cross-species extrapolation of accumulation and toxicity data. PMID:24193403

Qiu, Hao; Peijnenburg, Willie J G M; van Gestel, Cornelis A M; Vijver, Martina G

2014-01-01

166

The bioavailability of chemicals in soil for earthworms  

USGS Publications Warehouse

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.

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

2004-01-01

167

Examining the relationship between garlic mustard (Alliaria petiolata) and European earthworms.  

E-print Network

??Our goal was to characterize the interactive feedback between garlic mustard (Alliaria petiolata) and European earthworm species in southwest Ohio. Earthworm community composition, abundance and… (more)

Zelles, Alexandra M.

2012-01-01

168

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

PubMed

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

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

2013-06-01

169

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

PubMed

Understanding the interaction of nanoparticles with biological fluid is important for predicting the behavior and toxicity of nanoparticles in living systems. The earthworm Eisenia andrei was exposed to citrate-coated silver nanoparticles (cAgNPs), and the interaction of cAgNPs with earthworm coelomic fluid (ECF), the cytotoxicity of cAgNPs in earthworm coelomocytes was assessed. The neutral red retention assay showed a reduction in lysosomal stability after exposure. The toxicity of silver ions dissolved from cAgNPs in the soil medium was not significant. The aggregation and dissolution of cAgNPs increased in ECF, which contains various electrolytes that alter the properties of nanoparticles, and their subsequent toxicity. Microscopic and dissolution studies demonstrated that the aggregation of cAgNPs rapidly increased, and readily dissolved in ECF. The bioavailability of cAgNPs to earthworms induced lysosomal cytotoxicity. This is the first report to test the interaction and lysosomal cytotoxicity of nanoparticles in earthworm biofluids. Copyright © 2014 John Wiley & Sons, Ltd. PMID:24532537

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

2014-11-01

170

Computerized Manufacturing Cell An Earthworm and a Leech robot  

E-print Network

Computerized Manufacturing Cell An Earthworm and a Leech robot Flexible Robot Gripper Professor S completed recently involved developing a unique design and development of a biologically inspired robot

Major, Arkady

171

Greenhouse-gas emissions from soils increased by earthworms  

NASA Astrophysics Data System (ADS)

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

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

2013-03-01

172

Root foraging influences plant growth responses to earthworm foraging.  

PubMed

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

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

2014-01-01

173

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

PubMed

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

Morris, D E; Pivnick, K A

1991-11-01

174

Root Foraging Influences Plant Growth Responses to Earthworm Foraging  

PubMed Central

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

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

2014-01-01

175

Checklist of earthworms (Oligochaeta: Lumbricidae) from Germany.  

PubMed

A checklist of the German earthworm fauna (Oligochaeta: Lumbricidae) is presented, including published data, data from reports, diploma- and PhD- theses as well as unpublished data from museum collections, research institutions and private persons. Overall, 16,000 datasets were analyzed to produce the first German checklist of Lumbricidae. The checklist comprises 46 earthworm species from 15 genera and provides ecological information, zoogeographical distribution type and information on the species distribution in Germany. Only one species, Lumbricus badensis Michaelsen, 1907, is endemic to Germany, whereas 41% are peregrine. As there are 14 species occurring exclusively in the southern or eastern part of Germany, the species numbers in German regions increase from north to south. PMID:25283656

Lehmitz, Ricarda; Römbke, Jörg; Jänsch, Stephan; Krück, Stefanie; Beylich, Anneke; Graefe, Ulfert

2014-01-01

176

Determination of arsenic compounds in earthworms  

Microsoft Academic Search

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

Anita Geiszinger; Walter Goessler; Doris Kuehnelt; W. Kosmus; K. Francesconi

1998-01-01

177

Differences in burrowing behaviour and spatial interaction between the two earthworm species Aporrectodea nocturna and Allolobophora chlorotica  

Microsoft Academic Search

To study intraspecific and interspecific interactions between different ecological types of earthworm, the burrowing behaviour\\u000a of two earthworm species (the anecic earthworm Aporrectodea nocturna and the endogeic earthworm Allolobophora chlorotica) was observed in a microcosm. Earthworms were either alone in the microcosm, together with a conspecific earthworm, or with\\u000a an earthworm of the other species. Observations under red light, including

Y. Capowiez

2000-01-01

178

Determination of arsenic compounds in earthworms  

SciTech Connect

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.

Geiszinger, A.; Goessler, W.; Kuehnelt, D.; Kosmus, W. [Karl-Franzens-Univ., Graz (Austria). Inst. for Analytical Chemistry] [Karl-Franzens-Univ., Graz (Austria). Inst. for Analytical Chemistry; Francesconi, K. [Odense Univ. (Denmark). Inst. of Biology] [Odense Univ. (Denmark). Inst. of Biology

1998-08-01

179

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

PubMed

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

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

2013-11-01

180

Exotic earthworms of great lakes forests: A search for indicator plant species in maple forests  

Microsoft Academic Search

The invasion of exotic earthworms in previously earthworm-free northern deciduous forests has been linked to the disappearance of forest floor litter, declines in plant species richness, and the development of monotypic stands of Carex pensylvanica. However, the impact of exotic earthworms on the regeneration of trees and understory plants is largely unknown. We examined the relationships between earthworm density, plant

Kathryn Corio; Amy Wolf; Michael Draney; Gary Fewless

2009-01-01

181

The hormone-like effect of earthworm casts on plant growth  

Microsoft Academic Search

The fertilizing effect of earthworm casts depends on microbial metabolites, mainly growth regulators. The hormone-like effect of earthworm casts is discussed with reference to the literature and ad hoc experiments. When used in plant propagation, earthworm casts promote root initiation and root biomass and increase root percentage. When applied as a casing layer, earthworm casts stimulate carpophore formation in Agaricus

U. Tomati; A. Grappelli; E. Galli

1988-01-01

182

Physicochemical properties of earthworm casts and uningested parent soil from selected sites in southwestern Nigeria  

Microsoft Academic Search

Earthworms modify both the physical and chemical properties of soils. In a study on the possible modification of soil properties by earthworms, earthworm casts and uningested A and B soil horizons from three sites in southwestern Nigeria were analysed for selected physical and chemical properties. The casts were derived from the earthworm species Hyperiodrilus africanus. Results were analysed by a

D. J. Oyedele; P. Schjønning; A. A. Amusan

2006-01-01

183

Why are earthWorms important? Only a few decades ago, the predominating  

E-print Network

Earthworms #12;#12;Why are earthWorms important? Only a few decades ago, the predominating thought was that earthworms were not very important for agriculture. Emphasis was placed on physical and chemical aspects. Earthworms are among the most visible of soil organisms and have received considerable attention. They play

Kaye, Jason P.

184

Earthworm excreta attract soil springtails: laboratory experiments on Heteromurus Nitidus (Collembola: Entomobryidae)  

E-print Network

1 Earthworm excreta attract soil springtails: laboratory experiments on Heteromurus Nitidus are often found more abundantly in soils with earthworms than in soils without. Earthworms probably create a favourable environment for microarthropods but few studies have aimed to explain this earthworm effect

Paris-Sud XI, Université de

185

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

SciTech Connect

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.

Gibbs, M.H. [Univ. of Tennessee, Knoxville, TN (United States). Center for Environmental Biotechnology; Wicker, L.F.; Stewart, A.J. [Oak Ridge National Lab., TN (United States). Environmental Sciences Div.

1996-03-01

186

Potential effects of earthworms on leaf-chewer performance  

Microsoft Academic Search

Detritivores affect plant performance and therefore have the potential indirectly to affect above-ground herbivore populations. 2. In a microcosm study we asked whether changes in the performance of two plant species, Cardamine hirsuta L. and Veronica persica Poiret., arising from the activity of various earthworm communities influenced the consumption rate and development of a leaf-chewer, Mamestra brassicae L. 3. Earthworms

J. E. Newington; H. Setälä; T. M. Bezemer; T. H. Jones

2004-01-01

187

Clostridiaceae and Enterobacteriaceae as active fermenters in earthworm gut content  

Microsoft Academic Search

The earthworm gut provides ideal in situ conditions for ingested heterotrophic soil bacteria capable of anaerobiosis. High amounts of mucus- and plant-derived saccharides such as glucose are abundant in the earthworm alimentary canal, and high concentrations of molecular hydrogen (H2) and organic acids in the alimentary canal are indicative of ongoing fermentations. Thus, the central objective of this study was

Pia K Wüst; Marcus A Horn; Harold L Drake

2011-01-01

188

Recovery of Native Earthworms in Abandoned Tropical Pastures  

Microsoft Academic Search

Regeneration of secondary forests is recognized as an important means for the recovery of native species biodiversity in human-disturbed tropical lands. Native earthworms are often replaced with exotic spe- cies after deforestation. We studied changes in earthworm diversity and community structure along a chro- nosequence of abandoned tropical pastures in the Cayey Mountains of Puerto Rico. This chronosequence con- sisted

Yaniria Sanchez-De Leon; Xiaoming Zou; Sonia Borges; Honghua Ruan

2003-01-01

189

Earthworms, water infiltration and soil stability: Some new assessments  

Microsoft Academic Search

Water infiltration (by limiting surface water run-off) and stable crumb formation (by increasing top infiltration and decreasing slaking) are two key soil factors greatly affected by earthworms. Because of the great number of environmental variables controlling (1) earthworm populations; (2) their physical rôle behaviour; (3) their feeding behaviour inducing faeces composition; and (4) the microbial activity stabilizing faeces to crumbs,

Marcel B. Bouché; Fathel Al-Addan

1997-01-01

190

Ecosystem Consequences of Exotic Earthworm Invasion of North Temperate Forests  

Microsoft Academic Search

The invasion of north temperate forests by exotic species of earthworms is an important issue that has been overlooked in the study and management of these forests. We initiated research to address the hypothesis that earthworm invasion will have large consequences for nutrient retention and uptake in these ecosystems. In this special feature of Ecosystems, we present five papers describing

Patrick J. Bohlen; Peter M. Groffman; Timothy J. Fahey; Melany C. Fisk; Esteban Suarez; Derek M. Pelletier; Robert T. Fahey

2004-01-01

191

Cadmium, nickel, lead, and zinc in earthworms from roadside soil  

Microsoft Academic Search

Cd, Ni, Pb, and Zn in soils and earthworms along two Maryland highways decreased with increasing distance (10, 20, 40, 80, and 160 ft) from the roadway. Metals were quantified by atomic absorption spectrophotometry. Metal residues were higher at the location along each highway where traffic volume was greater. Correlations between residues in earthworms and soil decreased with decreasing atomic

Charles D. Gish; Robert E. Christensen

1973-01-01

192

The bioavailability of chemicals in soil for earthworms  

Microsoft Academic Search

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

R. Lanno; J. Wells; J. Conder; K. Bradham; N. Basta

2004-01-01

193

Bioconcentration and biokinetics of heavy metals in the earthworm  

Microsoft Academic Search

This study examines the steady state and non-steady state kinetics of five metals, cadmium, copper, lead, nickel, and zinc in earthworms. The steady state kinetics are based on field studies in which worms from contaminated and uncontaminated sites were collected and measurements were made of concentrations in the earthworms and soils. For each of the metals, evidence suggests that bioconcentration

Edward F. Neuhauser; Zoran V. Cukic; Michael R. Malecki; Raymond C. Loehr; Patrick R. Durkin

1995-01-01

194

Literature-derived bioaccumulation models for earthworms: Development and validation  

Microsoft Academic Search

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

G. W. II Suter; J. J. Beauchamp; R. A. Efroymson

1999-01-01

195

Field decomposition of leaf litters: earthworm–microorganism interactions —the ploughing-in effect  

Microsoft Academic Search

We describe a new decomposition model including the consequences of earthworm mechanical activity, especially the ploughing-in effect. In an experiment we tested this ploughing-in effect on the disappearance of leaf litter from four tree species (sessile oak, Quercus petraea L., holm oak, Quercus ilex L., sweet chestnut, Castanea sativa Mill and beech, Fagus sylvatica L.) during two 2y exposure at

J. Cortez; M. B. Bouché

1998-01-01

196

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

NASA Astrophysics Data System (ADS)

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.

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

2008-12-01

197

Agricultural practices and the spatial distribution of earthworms in maize fields. Relationships between earthworm abundance, maize plants and soil compaction  

Microsoft Academic Search

The relationships between the spatial heterogeneity of maize fields, due to row-cropping and farm machinery traffic, and earthworm abundance were studied in three plots receiving different organic matter treatments: no organic fertilizer, pig slurry and farmyard-manure. In all plots, there was no significant effect of farm machinery traffic although there was a tendancy for earthworms to be less abundant under

F. Binet; V. Hallaire; P. Curmi

1997-01-01

198

Effects of European Earthworm Invasion on Soil Characteristics in Northern Hardwood Forests of Minnesota, USA  

Microsoft Academic Search

European earthworms are colonizing worm-free hardwood forests across North America. Leading edges of earthworm invasion in\\u000a forests of northern Minnesota provide a rare opportunity to document changes in soil characteristics as earthworm invasions\\u000a are occurring. Across leading edges of earthworm invasion in four northern hardwood stands, increasing total earthworm biomass\\u000a was associated with rapid disappearance of the O horizon. Concurrently,

Cindy M. Hale; Lee E. Frelich; Peter B. Reich; John Pastor

2005-01-01

199

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

SciTech Connect

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.

Chana, L.W.; Smith, K. [Environmental Protection Agency, Cincinnati, OH (United States)

1995-12-31

200

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

PubMed

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

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

2013-06-01

201

DNA damage and biochemical toxicity of antibiotics in soil on the earthworm Eisenia fetida.  

PubMed

DNA damage and changes in enzyme activities were used as biomarkers to evaluate the genotoxicity and oxidative stress of tetracycline and chlortetracycline on the earthworm Eisenia fetida. The results showed that both antibiotics induced significant genotoxicity on earthworms in a dose-dependent manner (p<0.01) with chlortetracycline having a stronger effect than tetracycline in the short term. The tests on the activities of superoxide dismutase (SOD) and catalase (CAT) enzymes further indicated biochemical stresses induced by the antibiotics. An N-shaped activity pattern was noted with the enzyme activities being stimulated first, then inhibited, and stimulated again with increasing concentration. The induced activity of SOD or CAT could scavenge oxygen free radicals and protect the organisms against oxidative stress by alleviating the corresponding DNA damage. Compared to enzyme activities, DNA damage as a biomarker was more sensitive and is thus more suitable for detecting low concentration exposure and diagnosing the genotoxicity of contaminants in terrestrial environment. PMID:22647195

Dong, Luxi; Gao, Jie; Xie, Xiujie; Zhou, Qixing

2012-09-01

202

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

NASA Astrophysics Data System (ADS)

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

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

2014-06-01

203

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

PubMed

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

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

2012-11-01

204

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

PubMed

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

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

2013-04-01

205

Enantioselective acute toxicity effects and bioaccumulation of furalaxyl in the earthworm (Eisenia foetida).  

PubMed

The enantioselectivities of individual enantiomers of furalaxyl in acute toxicity and bioaccumulation in the earthworm (Eisenia foetida) were studied. The acute toxicity was tested by filter paper contact test. After 48 h of exposure, the calculated LC50 values of the R-form, rac-form, and S-form were 2.27, 2.08, and 1.22 µg cm(-2), respectively. After 72 h of exposure, the calculated LC50 values were 1.90, 1.54, and 1.00 µg cm(-2), respectively. Therefore, the acute toxicity of furalaxyl enantiomers was enantioselective. During the bioaccumulation experiment, the enantiomer fraction of furalaxyl in earthworm tissue was observed to deviate from 0.50 and maintained a range of 0.55-0.60; in other words, the bioaccumulation of furalaxyl was enantioselective in earthworm tissue with a preferential accumulation of S-furalaxyl. The uptake kinetic of furalaxyl enantiomers fitted the first-order kinetics well and the calculated kinetic parameters were consistent with the low accumulation efficiency. PMID:24771637

Qin, Fang; Gao, Yongxin; Guo, Baoyuan; Xu, Peng; Li, Jianzhong; Wang, Huili

2014-06-01

206

Carbon-Mineral Interactions along an Earthworm Invasion Gradient  

NASA Astrophysics Data System (ADS)

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.

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

2010-12-01

207

Burrowing activity of the geophagous earthworm Pontoscolex corethrurus1 (Oligochaeta: Glossoscolecidae) in the presence of charcoal2  

E-print Network

1 Burrowing activity of the geophagous earthworm Pontoscolex corethrurus1 (Oligochaeta 12 The geophagous earthworm Pontoscolex corethrurus is frequently found in13 burnt tropical soils. Introduction7 8 The geophagous earthworm Pontoscolex corethrurus, an endogeic species9 feeding on soil

Paris-Sud XI, Université de

208

Does the deep-burrowing earthworm, Aporrectodea longa, compete with resident earthworm communities when introduced to pastures in south-eastern Australia?  

Microsoft Academic Search

Pastures in southern Australia are dominated by endogeic earthworms such as Aporrectodea caliginosa (Sav.). Introductions of the anecic earthworm, A. longa (Ude), which is mostly restricted to Tasmania at present, are likely to increase the functional diversity of local communities and thereby enhance plant production and agricultural sustainability. However, the potential impact of A. longa on resident earthworm communities first needs assessing.

Geoff Baker; Penny Carter; Vicki Barrett; Jeff Hirth; Pauline Mele; Cameron Gourley

2002-01-01

209

First evidence of the P-glycoprotein gene expression and multixenobiotic resistance modulation in earthworm.  

PubMed

Multixenobiotic resistance (MXR) is an important mechanism of cellular efflux mediated by ATP binding cassette (ABC) transporters that bind and actively remove toxic substrates from the cell. This study was the first to identify ABC transporter P-glycoprotein (P-gp/ABCB1) as a representative of the MXR phenotype in earthworm (Eisenia fetida). The identified partial cDNA sequence of ABCB1 overlapped with ABCB1 homologues of other organisms from 58.5 % to 72.5 %. We also studied the effect of five modulators (verapamil, cyclosporine A, MK571, probenecid, and orthovanadate) on the earthworm's MXR activity by measuring the accumulation of model substrates rhodamine B and rhodamine 123 in whole body tissue of the adult earthworm. MK571, orthovanadate, and verapamil significantly inhibited MXR activity, and rhodamine 123 turned out to better reflect MXR activity in that species than rhodamine B. Our results show that E. fetida can serve well as a test organism for environmental pollutants that inhibit MXR activity. PMID:24622780

Bošnjak, Ivana; Bielen, Ana; Babi?, Sanja; Sver, Lidija; Popovi?, Natalija Topi?; Strunjak-Perovi?, Ivan?ica; Což-Rakovac, Rozelinda; Klobu?ar, Roberta Sauerborn

2014-03-01

210

Metals and terrestrial earthworms (Annelida: Oligochaeta)  

USGS Publications Warehouse

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.

Beyer, W.N.

1981-01-01

211

Earthworms Produce phytochelatins in Response to Arsenic  

PubMed Central

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

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

2013-01-01

212

Effects of the removal of the invasive shrub, Chinese privet (Ligustrum sinense), on soil properties and earthworm communities.  

E-print Network

??This study investigated the possibility of a facilitative relationship between Chinese privet (Ligustrum sinense) and exotic earthworms. Earthworms and some soil properties were sampled five… (more)

Lobe, Joshua Waechter

2012-01-01

213

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

PubMed

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

Velki, Mirna; Hackenberger, Branimir K

2013-10-01

214

Earthworms of the Western United States. Part 1. Lumbricidae.  

National Technical Information Service (NTIS)

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 specie...

W. M. Fender

1985-01-01

215

Toxicity of metals to the earthworm Eisenia fetida  

Microsoft Academic Search

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.

E. F. Neuhauser; R. C. Loehr; D. L. Milligan; M. R. Malecki

1985-01-01

216

Protection of soil carbon by microaggregates within earthworm casts  

Microsoft Academic Search

Earthworms are known to play a role in aggregate formation and soil organic matter (SOM) protection. However, it is still unclear at what scale and how quickly earthworms manage to protect SOM. We investigated the effects of Aporrectodea caliginosa on aggregation and aggregate-associated C pools using 13C-labeled sorghum (Sorghum bicolor (L.) Moench) leaf residue. Two incubations were set up. The

Heleen Bossuyt; Johan Six; Paul F. Hendrix

2005-01-01

217

Effects of earthworms on Zn fractionation in soils  

Microsoft Academic Search

Laboratory incubation experiments were conducted to examine the effect of earthworm (Pheretima sp.) activity on soil pH, zinc (Zn) fractionation and N mineralization in three soils. No Zn uptake by earthworms was observed. Zinc addition decreased pH of red soil (soil 1) and hydragric paddy soil (soil 3) by 0.5 and 0.2 unit, respectively, but had no effect on alluvial

Jiemin Cheng; Ming H. Wong

2002-01-01

218

Cadmium-binding proteins induced in the earthworm  

Microsoft Academic Search

Earthworms,Eisenia foetida, grown in composts of different cadmium concentrations accumulated cadmium in a dose-dependent manner and the cadmium was bound to three different molecular weight cadmium-binding proteins induced in the earthworm. The three proteins were stable to heat treatment and accompanied by a concomitant increase of absorbance at 254 nm and not at 280 nm. Each of the three proteins

Kazuo T. Suzuki; Mitsuru Yamamura; Tadahiro Mori

1980-01-01

219

Ecotoxicological effects on earthworms of fresh and aged nano-sized zero-valent iron (nZVI) in soil.  

PubMed

Although nano-sized zero-valent iron (nZVI) has been used for several years for remediation of contaminated soils and aquifers, only a limited number of studies have investigated secondary environmental effects and ecotoxicity of nZVI to soil organisms. In this study we therefore measured the ecotoxicological effects of nZVI coated with carboxymethyl cellulose on two species of earthworms, Eisenia fetida and Lumbricus rubellus, using standard OECD methods with sandy loam and artificial OECD soil. Earthworms were exposed to nZVI concentrations ranging from 0 to 2000 mg nZVI kg soil(-1) added freshly to soil or aged in non-saturated soil for 30 d prior to exposure. Regarding avoidance, weight changes and mortality, both earthworm species were significantly affected by nZVI concentrations ?500 mg kg(-1)soil. Reproduction was affected also at 100 mg nZVI kg(-1). Toxicity effects of nZVI were reduced after aging with larger differences between soils compared to non-aged soils. We conclude that doses ?500 mg nZVI kg(-1) are likely to give acute adverse effects on soil organisms, and that effects on reproduction may occur at significantly lower concentrations. PMID:22595530

El-Temsah, Yehia S; Joner, Erik J

2012-09-01

220

Toxicity and bioaccumulation of ethofumesate enantiomers in earthworm Eisenia fetida.  

PubMed

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

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

2014-10-01

221

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

NASA Astrophysics Data System (ADS)

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.

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

2009-05-01

222

Report of the Second Stage in Development of a Standardized Laboratory Method for Assessing the Toxicity of Chemical Substances to Earthworms.  

National Technical Information Service (NTIS)

The inter-laboratory intercalibration ring test assessing the validity and reproducibility of proposed contact filter paper, artificial soil and an 'artisol' toxicity test for the earthworm E. foetida in 1981/2 involved the assessment of the toxicity of p...

C. A. Edwards

1984-01-01

223

How to reduce false positive results when undertaking in vitro genotoxicity testing and thus avoid unnecessary follow-up animal tests: Report of an ECVAM Workshop  

Microsoft Academic Search

Workshop participants agreed that genotoxicity tests in mammalian cells in vitro produce a remarkably high and unacceptable occurrence of irrelevant positive results (e.g. when compared with rodent carcinogenicity). As reported in several recent reviews, the rate of irrelevant positives (i.e. low specificity) for some studies using in vitro methods (when compared to this “gold standard”) means that an increased number

David Kirkland; Stefan Pfuhler; David Tweats; Marilyn Aardema; Raffaella Corvi; Firouz Darroudi; Azeddine Elhajouji; Hansruedi Glatt; Paul Hastwell; Makoto Hayashi; Peter Kasper; Stephan Kirchner; Anthony Lynch; Daniel Marzin; Daniela Maurici; Jean-Roc Meunier; Lutz Müller; Gerhard Nohynek; James Parry; Elizabeth Parry; Veronique Thybaud; Ray Tice; Jan van Benthem; Philippe Vanparys; Paul White

2007-01-01

224

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

PubMed Central

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 ?g/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

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

2012-01-01

225

Earthworms newly from Mongolia (Oligochaeta, Lumbricidae, Eisenia)  

PubMed Central

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

Blakemore, Robert J.

2013-01-01

226

Soil Biology & Biochemistry 38 (2006) 16081614 Endogeic earthworms differentially influence bacterial communities  

E-print Network

Soil Biology & Biochemistry 38 (2006) 1608­1614 Endogeic earthworms differentially influence C. Rilliga , Johan Sixb a Division of Biological Sciences, Microbial Ecology Program, The University November 2005 Available online 2 February 2006 Abstract Endogeic earthworm activities can strongly

Rilli, Matthias C.

227

Soil organic matter distribution and microaggregate characteristics as affected by agricultural management and earthworm activity  

E-print Network

within earthworm casts. Soil Biology and Biochemistry, 37,Earthworms and rate of break- down of soybean and maize residues in soil. Soil Biologyearthworm activity in a marine silt loam under pasture versus arable land. Biology

Pulleman, M M; Six, J; van Breemen, N; Jongmans, A G

2005-01-01

228

Earthworm effects on plant growth do not necessarily decrease with soil fertility  

Microsoft Academic Search

Earthworms are known to generally increase plant growth. However, because plant-earthworm interactions are potentially mediated\\u000a by soil characteristics the response of plants to earthworms should depend on the soil type. In a greenhouse microcosm experiment,\\u000a the responsiveness of plants (Veronica persica, Trifolium dubium and Poa annua) to two earthworm species (in combination or not) belonging to different functional groups (Aporrectodea.

Kam-Rigne Laossi; Amandine Ginot; Diana Cristina Noguera; Manuel Blouin; Sébastien Barot

2010-01-01

229

Acute toxicity of multi-walled carbon nanotubes, sodium pentachlorophenate, and their complex on earthworm Eisenia fetida.  

PubMed

Laboratory experiments were undertaken to relate biomarker responses to the toxicities of multi-walled carbon nanotubes (MWCNTs) and sodium pentachlorophenate (PCP-Na), both individually and combined. The acute toxicities of MWCNTs and PCP-Na on earthworm Eisenia fetida were studied through different exposure methods (filter paper contact test, immersion contact test, and artificial soil contact test). Enzyme activity and malondialdehyde (MDA) content in the earthworm E. fetida exposed to MWCNTs and PCP-Na in filter paper contact test, both individually and under combined exposure, were determined. After exposure, PCP-Na induced observable acute toxicity while the MWCNTs induced slight toxicity. Interestingly the earthworms exposed to the mixture of MWCNTs and PCP-Na demonstrated different expression of enzymatic biomarkers from those exposed to MWCNTs or PCP-Na alone. Our results indicated that the toxicity of PCP-Na on E. fetida may be alleviated by the appearance of MWCNTs for all exposure methods except for immersion contact test. PMID:24562180

Zhang, Liujun; Hu, Changwei; Wang, Weili; Ji, Funian; Cui, Yibin; Li, Mei

2014-05-01

230

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

SciTech Connect

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.

Spurgeon, D.J.; Tomlin, M.A.; Hopkin, S.P. [Univ. of Reading (United Kingdom)] [Univ. of Reading (United Kingdom)

1997-02-01

231

Comparative and combined acute toxicity of butachlor, imidacloprid and chlorpyrifos on earthworm, Eisenia fetida.  

PubMed

Various pesticides have become widespread contaminants of soils due to their large applications in agriculture and homes. An earthworm assay was used to assess the acute toxicity of butachlor, imidacloprid and chlorpyrifos with different modes of action. Ecotoxicities of these pesticides were compared for earthworm Eisenia fetida separately and in combination in artificial soil and contact filter paper tests. Imidacloprid was the most toxic for E. fetida with LC?? (lethal concentration 50) values three orders magnitude lower than that of butachlor and chlorpyrifos in both tests. The toxicity of the mixtures was compared to that predicted by the concentration addition (CA) model. According to the CA model, the observed toxicities of all binary mixtures were less than additive. However, for all the mixtures in 14 d artificial soil test, and mixtures of butachlor plus chlorpyrifos and imidacloprid plus chlorpyrifos in 48 h contact filter paper test, the difference in toxicity was less than 30%, hence it was concluded that the mixtures conformed to CA. The combined effects of the pesticides in contact filter paper tests were not consistent with the results in artificial soil toxicity tests, which may be associated with the interaction of soil salts with the pesticides. The CA model provides estimates of mixture toxicity that did not markedly underestimate the measured toxicity, and therefore the CA model is the most suitable to use in ecological risk assessments of the pesticides. PMID:24377448

Chen, Chen; Wang, Yanhua; Zhao, Xueping; Wang, Qiang; Qian, Yongzhong

2014-04-01

232

Exotic Earthworm Influence on Nitrogen Cycling in FACE Forest Soils  

NASA Astrophysics Data System (ADS)

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.

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

2010-12-01

233

Influence of earthworm invasion on soil microbial biomass and activity in a northern hardwood forest  

Microsoft Academic Search

Recent invasion and activity of exotic earthworms has profoundly altered the chemical and physical environment of surface soils in northern hardwood forests that previously had mor humus horizons. We investigated the influence of earthworm invasion on soil microbial biomass and activity in surface soils of Allegheny northern hardwood forests in central New York state. Earthworm activity in these sites had

Xuyong Li; Melany C Fisk; Timothy J Fahey; Patrick J Bohlen

2002-01-01

234

Abstract This study addressed differences between Dip-locardia spp. (a native North American earthworm) and  

E-print Network

earthworm) and Octolasion tyrtaeum (an introduced European species), with respect to behavior, influence on soil microbial bio- mass, and plant uptake of N in tallgrass prairie soils. We manipulated earthworms to addition of earthworms, seedlings of An- dropogon gerardii (a dominant tallgrass) were estab- lished

Blair, John

235

Toxicity of nickel to the earthworm and the applicability of the neutral red retention assay  

E-print Network

Toxicity of nickel to the earthworm and the applicability of the neutral red retention assay JANECK of exposure to a nickel-chloride spiked loamy sand soil. The ability of a simple earthworm biomarker-red retention time showed large individual variation for the earthworms within each exposure concentration

Hopkin, Steve

236

Trophic transfer of fatty acids from gut microbiota to the earthworm Lumbricus terrestris L  

Microsoft Academic Search

The diet of earthworms includes soil organic matter, soil microbes and other microfauna, but the relative contribution of these dietary components to earthworm nutrition is not well known. Analysis of fatty acid (FA) profiles can reveal trophic relationships in soil food webs, leading to a better understanding of the energy and nutrient flows from microbiota to earthworms. The objective of

Luis Sampedro; Richard Jeannotte; Joann K. Whalen

2006-01-01

237

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

E-print Network

1 Balkanized research in ecological engineering revealed by a bibliometric analysis of earthworms are characterized by the use of organisms rather than energy-consuming technologies. Although earthworms of the association of ,,earthworms and other terms such as ecosystem services (primary production, nutrient cycling

Paris-Sud XI, Université de

238

Earthworms (Millsonia anomala, Megascolecidae) do not increase rice growth1 through enhanced nitrogen mineralization.2  

E-print Network

1 Earthworms (Millsonia anomala, Megascolecidae) do not increase rice growth1 through enhanced (LEST), UMR 137, IRD, Bondy, 93143,6 France.7 8 Abstract9 10 Earthworms have been shown to increase in the presence of earthworms (Millsonia anomala,15 Megascolecidae) and demonstrated that enhanced nitrogen

Paris-Sud XI, Université de

239

Is earthworms' dispersal facilitated by the ecosystem engineering activities of conspecifics?1 Gal Caro1*  

E-print Network

1 Is earthworms' dispersal facilitated by the ecosystem engineering activities of conspecifics?1 2 of earthworm's galleries on their speed of25 movements during dispersal events in the soil. We quantified, by using X-rays, the dispersal26 behaviour of earthworms in the soil. The observations were conducted

Paris-Sud XI, Université de

240

Influence of ground cover on earthworm communities in an unmanaged beech forest: linear gradient studies  

E-print Network

1 Influence of ground cover on earthworm communities in an unmanaged beech forest: linear gradient-mail: jean-francois.ponge@wanadoo.fr Running title: Influence of ground cover on earthworm species communities Abstract: Micro-scale changes in earthworm communities and ground cover types were studied along

Paris-Sud XI, Université de

241

Location-dependency of earthworm response to reduced tillage on sandy soil Monika Joschko a,  

E-print Network

Location-dependency of earthworm response to reduced tillage on sandy soil Monika Joschko a for Advanced Studies (FRIAS), Albertstr. 19, D-79104 Freiburg, Germany 1. Introduction Earthworms belong., 2008). In these soils earthworms should therefore be impaired as little as possible by management

Timmer, Jens

242

Comparisons of metal accumulation and excretion kinetics in earthworms (Eisenia fetida) exposed to contaminated  

E-print Network

Comparisons of metal accumulation and excretion kinetics in earthworms (Eisenia fetida) exposed are present at increased concentrations in earthworms inhabiting contami- nated soils (for references see of earthworms to assim- ilate metals has led to this group being recommended for monitoring the spatial

Hopkin, Steve

243

Effects of Earthworms on Soil Organic Matter and Nutrient Dynamics at a Landscape Scale over Decades  

E-print Network

1 Effects of Earthworms on Soil Organic Matter and Nutrient Dynamics at a Landscape Scale over, and severe depletion of soil invertebrate communities, especially earthworms (Decaëns et al. 1994; Lavelle et al. 1994). The contributions of earthworms to soil fertility have been described in several hundreds

Paris-Sud XI, Université de

244

Large-Scale Effects of Earthworms on Soil Organic Matter and Nutrient Patrick Lavelle,1  

E-print Network

1 Large-Scale Effects of Earthworms on Soil Organic Matter and Nutrient Dynamics Patrick Lavelle,1 and a severe depletion of soil invertebrate communities, especially earthworms (Lavelle et al. 1994). The contribution of earthworms to processes of soil fertility has been described in several hundred papers

Paris-Sud XI, Université de

245

The impact of cadmium and mercury contamination on reproduction and body mass of earthworms  

Microsoft Academic Search

The accumulation of heavy metals in the tissues of earthworms is a helpful indicator of environmental contaminati - on. The degree of substrate contamination can be additionally evaluated on the basis of survivability, reproduction and body mass of earthworms. In this study Eisenia fetida Sav. earthworms were exposed to a series of increasing concentrations of cadmium and mercury. The numbers

S. Lapinski; M. Rosciszewska

246

Inorganic and organic phosphorus pools in earthworm casts (Glossoscolecidae) and a Brazilian rainforest Oxisol  

E-print Network

Inorganic and organic phosphorus pools in earthworm casts (Glossoscolecidae) and a Brazilian We compared differences in soil phosphorus fractions between large earthworm casts (Family-input fertilization and SEC received no fertilization. We found that earthworm casts had higher levels of organic

Lehmann, Johannes

247

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

NASA Astrophysics Data System (ADS)

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.

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

2011-12-01

248

Interactions between residue placement and earthworm ecological strategy affect aggregate turnover and N 2O dynamics in agricultural soil  

Microsoft Academic Search

Previous laboratory studies using epigeic and anecic earthworms have shown that earthworm activity can considerably increase nitrous oxide (N2O) emissions from crop residues in soils. However, the universality of this effect across earthworm functional groups and its underlying mechanisms remain unclear. The aims of this study were (i) to determine whether earthworms with an endogeic strategy also affect N2O emissions;

Georgios Giannopoulos; Mirjam M. Pulleman; Jan Willem Van Groenigen

2010-01-01

249

Fate and uptake of pharmaceuticals in soil-earthworm systems.  

PubMed

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 (14)C-labeled carbamazepine, diclofenac, fluoxetine, and orlistat in soil-earthworm systems. Sorption coefficients increased in the order of carbamazepine < diclofenac < fluoxetine < orlistat. Dissipation of (14)C varied by compound, and for orlistat, there was evidence of formation of nonextractable residues. Uptake of (14)C was seen for all compounds. Depuration studies showed complete elimination of (14)C for carbamazepine and fluoxetine treatments and partial elimination for orlistat and diclofenac, with greater than 30% of the (14)C remaining in the tissue at the end of the experiment. Pore-water-based bioconcentration factors (BCFs), based on uptake and elimination of (14)C, 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

Carter, Laura J; Garman, Catherine D; Ryan, James; Dowle, Adam; Bergström, Ed; Thomas-Oates, Jane; Boxall, Alistair B A

2014-05-20

250

Laboratory Protocol for Measuring the Bioaccumulation of Mercury by Earthworms  

NASA Astrophysics Data System (ADS)

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.

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

2007-12-01

251

Comparative toxicity of pentachlorophenol to three earthworm species in artificial soil  

SciTech Connect

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.

Fitzgerald, D.; Lanno, R.P.; Farwell, A.; Dixon, D.G. [Univ. of Waterloo, Ontario (Canada). Dept. of Biology

1994-12-31

252

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

SciTech Connect

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.

Meier, J.R.; Chang, L.W.; Meckes, M.C.; Smith, M.K. [Environmental Protection Agency, Cincinnati, OH (United States); Jacobs, S. [DynCorp, Cincinnati, OH (United States); Torsella, J. [Oak Ridge Inst. of Science and Education, Cincinnati, OH (United States)

1997-05-01

253

Approach and Avoidance Motivation  

Microsoft Academic Search

In this article, we introduce this special issue by establishing a conceptual foundation for the distinction between approach and avoidance motivation. We do so primarily by explicating several reasons why the approach–avoidance distinction should be viewed as fundamental and basic to the study of human behavior. In addition, we compare and contrast the approach–avoidance designation with other designations that have

Andrew J. Elliot; Martin V. Covington

2001-01-01

254

The influence of soil characteristics on the toxicity of four chemicals to the earthworm Eisenia fetida andrei (Oligochaeta)  

Microsoft Academic Search

The acute toxicity of Cd (chloride), chloroacetamide, 3,4-dichloroaniline and pentachlorophenol to the earthworm Eisenia fetida andrei was determined using the OECD (1984) artificial soil and contact testing procedures. To investigate the influence of two soil characteristics (pH and organic-matter content), the toxicity of the chemicals was also determined in two natural sandy soils. It is concluded that the filter-paper contact

C. A. M. van Gestel; W. A. Dis

1988-01-01

255

Ecotoxicity of silver nanoparticles on earthworm Eisenia fetida: responses of the antioxidant system, acid phosphatase and ATPase  

Microsoft Academic Search

Ecotoxicity of nanoparticles has received growing attention in recent years. This study investigated the influence of silver nanoparticles (Ag-NP) on earthworm Eisenia fetida. The experiment was performed with five test groups: control (without Ag-NP), 10?nm Ag-NP groups (20, 100 or 500?mg?kg) and positive control (787?mg?kg AgNO3). After 14-day acute exposure, activities of various enzymes, including glutathione S-transferase (GST), glutathione reductase

Changwei Hu; Mei Li; Weili Wang; Yibin Cui; Jun Chen; Liuyan Yang

2012-01-01

256

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

SciTech Connect

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.

Wilborn, D.; Bollman, M.; Linder, G. [ManTech Environmental Technology, Inc., Corvallis, OR (United States)

1994-12-31

257

Bioaccumulation and single and joint toxicities of penta-BDE and cadmium to earthworms ( Eisenia fetida ) exposed to spiked soils  

Microsoft Academic Search

Bioaccumulation of penta-BDE (DE-71) in earthworms (Eisenia fetida) and the induced toxicities on the growth and reproduction of earthworms were investigated. All the major congeners in DE-71\\u000a could be bioaccumulated in earthworms and the concentration found in earthworms correlated to the spiked concentration in\\u000a soil. DE-71 might inhibit the growth and reproduction of cocoons and juveniles of earthworms. The toxicities

ShuZhen Zhu; Man Liu; ShengYan Tian; LingYan Zhu

2010-01-01

258

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

SciTech Connect

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.

Moiseenko, Vitali, E-mail: vmoiseenko@bccancer.bc.ca [Department of Medical Physics, Vancouver Cancer Centre, British Columbia Cancer Agency, Vancouver, BC (Canada); Wu, Jonn [Department of Radiation Oncology, Vancouver Cancer Centre, British Columbia Cancer Agency, Vancouver, BC (Canada); Hovan, Allan [Department of Oral Oncology, Vancouver Cancer Centre, British Columbia Cancer Agency, Vancouver, BC (Canada); Saleh, Ziad; Apte, Aditya; Deasy, Joseph O. [Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, NY (United States); Harrow, Stephen [Department of Radiation Oncology, Vancouver Cancer Centre, British Columbia Cancer Agency, Vancouver, BC (Canada); Rabuka, Carman; Muggli, Adam [Department of Oral Oncology, Vancouver Cancer Centre, British Columbia Cancer Agency, Vancouver, BC (Canada); Thompson, Anna [Department of Radiation Oncology, Vancouver Cancer Centre, British Columbia Cancer Agency, Vancouver, BC (Canada)

2012-03-01

259

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

PubMed

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

Rajiv, P; Rajeshwari, Sivaraj; Rajendran, Venckatesh

2014-11-01

260

Recombinant Protein Production of Earthworm Lumbrokinase for Potential Antithrombotic Application  

PubMed Central

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

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

2013-01-01

261

Combined effects of oxytetracycline and Pb on earthworm Eisenia fetida.  

PubMed

Combined effects of oxytetracycline (OTC) and Pb on lysosomal membrane stability and coelomocyte apoptosis of earthworm were studied in the paper. Compared with control, the lysosomal membrane stability decreased and coelomocyte apoptosis increased in the treatments of single OTC and Pb contamination. As for compound pollution, combined effect of (5 mg/kg OTC+50 mg/kg Pb) treatment on earthworm lysosomal was synergistic (except 28 d). However, it was antagonistic at higher concentration of (10 mg/kg OTC+50 mg/kg Pb) and (20 mg/kg OTC+50 mg/kg Pb) treatment. In addition, coelomocyte apoptosis of earthworm decreased significantly compared with single OTC, indicating an antagonistic reaction. And joint toxicity of OTC and Pb decreased significantly with the increasing OTC concentration. PMID:24607684

Gao, Minling; Zhou, Qian; Song, Wenhua; Ma, Xiaojun

2014-03-01

262

Accumulation of chlorinated benzenes in earthworms  

SciTech Connect

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.

Beyer, W.N. [Patuxent Wildlife Research Center, Laurel, MD (United States)] [Patuxent Wildlife Research Center, Laurel, MD (United States)

1996-12-31

263

Earthworms facilitate carbon sequestration through unequal amplification of carbon stabilization compared with mineralization  

NASA Astrophysics Data System (ADS)

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.

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

264

Automatic Collision Avoidance Technology (ACAT)  

NASA Technical Reports Server (NTRS)

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.

Swihart, Donald E.; Skoog, Mark A.

2007-01-01

265

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

PubMed Central

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

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

2012-01-01

266

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

PubMed

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

Bielská, Lucie; Šmídová, Klára; Hofman, Jakub

2014-02-01

267

Avoidable mortality in Lithuania.  

PubMed Central

STUDY OBJECTIVE--The study aimed to analyse avoidable mortality in Lithuania as an index of the quality of health care and to assess trends in avoidable mortality from 1970-90. SETTING AND PARTICIPANTS--All deaths of Lithuanian residents aged between 0 and 64 years between 1970 and 1990 were analysed. MEASUREMENTS AND MAIN RESULTS--Twenty seven per cent of all deaths in this age group were avoidable. Avoidable deaths were grouped into preventable and treatable ones. Treatable causes of death accounted for 54%, and preventable, 46% of avoidable mortality. Time trends showed that general mortality and mortality from avoidable causes of death in this age group were almost stable between 1970 and 1990. Mortality from treatable causes of death fell, while deaths from preventable causes increased. The results in the preventable group were greatly affected by deaths from malignant neoplasms of trachea, bronchus, and lungs. Differences were noted between the sexes in total mortality as well as in avoidable mortality. CONCLUSIONS--Avoidable causes of death are relatively common and, consequently, they are of practical importance for public health and studies of the health care quality in Lithuania. Reorganisation of health care is to be carried out and considerable emphasis will be placed on health education, promotion, and prevention, as primary prevention measures have not been effective thus far. PMID:7629464

Gaizauskiene, A; Gurevicius, R

1995-01-01

268

Heavy metal concentrations in earthworms from soil amended with sewage sludge  

USGS Publications Warehouse

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.

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

1982-01-01

269

REGULAR ARTICLE Earthworm effects on plant growth do not necessarily  

E-print Network

(Veronica persica, Trifolium dubium and Poa annua) to two earthworm species (in combination or not. Mineral fertilization, in the presence of L. terrestris, also reduced the total biomass of V. persica. L. terrestris did not only affect plant growth. In P. annua and V. persica A. caliginosa and L. terrestris also

Boyer, Edmond

270

Leaf Litter Disappearance in Earthworm-Invaded Northern  

E-print Network

Leaf Litter Disappearance in Earthworm-Invaded Northern Hardwood Forests: Role of Tree Species, and forest floor structure and composition are not well understood. For 2 years, we compared disappearance Department of Forest Resources, University of Minnesota, 1530 N. Cleveland Ave., St. Paul, Minnesota 55108

Minnesota, University of

271

Earthworm Population Studies : a Comparison of Sampling Methods  

Microsoft Academic Search

SVENDSEN1 showed that the estimate of an earthworm population obtained by hand sorting soil samples was much greater than that by the prevalent method of bringing worms to the soil surface with potassium permanganate solution, and so emphasized that, although laborious, hand sorting was more accurate for population studies. The accuracy of estimates by hand sorting has not been studied

F. Raw

1960-01-01

272

Do earthworms increase N2O emissions in ploughed grassland?  

Microsoft Academic Search

Earthworm activity has been reported to lead to increased production of the greenhouse gas nitrous oxide (N2O). This is due to emissions from worms themselves, their casts and drilosphere, as well as to general changes in soil structure. However, it remains to be determined how important this effect is on N2O fluxes from agricultural systems under realistic conditions in terms

C. Bertora; Vliet van P. C. J; E. W. J. Hummelink; Groenigen van J. W

2007-01-01

273

Earthworm casting: Stabilization or destabilization of soil structure?  

Microsoft Academic Search

The aim of the study was to determine the effect of the gut passage through earthworms on the aggregate stability of soils varying in texture, carbonate and organic matter content. The soil material used originated from the Ap and B horizon of a loam soil (Gleyic Luvisol) and from the Ap and P horizon of a clay soil (Calcaric-Vertic Cambisol).

Stefan Schrader; Haiquan Zhang

1997-01-01

274

Do earthworms increase N 2O emissions in ploughed grassland?  

Microsoft Academic Search

Earthworm activity has been reported to lead to increased production of the greenhouse gas nitrous oxide (N2O). This is due to emissions from worms themselves, their casts and drilosphere, as well as to general changes in soil structure. However, it remains to be determined how important this effect is on N2O fluxes from agricultural systems under realistic conditions in terms

Chiara Bertora; Petra C. J. van Vliet; Eduard W. J. Hummelink; Jan Willem van Groenigen

2007-01-01

275

Mechanisms of stabilization of earthworm casts and artificial casts  

Microsoft Academic Search

Fresh casts were collected from the earthworm species Aporrectodea caliginosa, and artificial casts were also made. The casts were subjected to ageing, drying-rewetting, and sterilization by hexanol vapour. Clay dispersion was determined, as a measure of the lack of stability of the casts. Two soils were used, the topsoil of a recently reclaimed polder soil in the Netherlands and the

J. C. Y. Marinissen; A. R. Dexter

1990-01-01

276

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...

277

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...

278

Earthworm Biomass Measurement: A Science Activity for Middle School.  

ERIC Educational Resources Information Center

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)

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

2000-01-01

279

Earthworm ecological groupings based on 14C analysis  

Microsoft Academic Search

We report the first use of 14C isotope analysis to investigate the ecological grouping of earthworms. Mature endogeic (Allolobophora caliginosa), mature epigeic (Lumbricus rubellus), and semimature anecic worms (A. longa) were collected in September 2002 from a woodland site at Lancaster, UK. Because anecic worms are known to have a variable feeding behaviour and can show dietary changes during ontogeny,

María Jesús I. Briones; M. H. Garnett; T. G. Piearce

2005-01-01

280

Microbial activity and nutrient dynamics in earthworm casts (Lumbricidae)  

Microsoft Academic Search

Microbial respiration, microbial biomass and nutrient requirements of the microflora (C, N, P) were studied in the food substrate (soil taken from the upper 3 cm of the mineral soil of a beech wood on limestone), the burrow walls and the casts of the earthworm Aporrectodea caliginosa (Savigny). The passage of the soil through the gut caused an increase in

S. Scheu

1987-01-01

281

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...

282

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

PubMed Central

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

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

2011-01-01

283

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

SciTech Connect

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.

Walsh, P. [Laval Univ. Research Center, Quebec (Canada)]|[Ministere de l`Environnement et de la Faune du Quebec (Canada); El Adlouni, C.; Mukhopadhyay, M.J.; Nadeau, D.; Poirier, G.G. [Laval Univ. Research Center, Quebec (Canada); Viel, G. [CreaLab., Quebec (Canada)

1995-05-01

284

Urban soil biomonitoring by beetle and earthworm populations  

SciTech Connect

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.

Janossy, L.; Bitto, A. [ELTE Univ., Budapest (Hungary)

1995-12-31

285

Culturing earthworms on pig manure and the effect of replacing trash fish by earthworms on the growth performance of Catfish (Clarias macrocephalus x Clarias gariepinus)  

Microsoft Academic Search

The purpose of the present study was to evaluate the nutritive value of earthworms Perionyx excavatus as protein source feed in growing Catfish (Clarias macrocephalus x Clarias gariepinus) rations. Earthworms were cultured on manure from pigs fed a balanced concentrate feed. Their proximate and amino acid composition was determined. Growing Catfish were fed a diet containing 30% crude protein (CP)

Nguyen Duy; Quynh Tram; Duc Ngoan; Brian Ogle

286

Assessing the ecotoxicological effects of long-term contaminated mine soils on plants and earthworms: relevance of soil (total and available) and body concentrations.  

PubMed

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

García-Gómez, Concepción; Esteban, Elvira; Sánchez-Pardo, Beatriz; Fernández, María Dolores

2014-09-01

287

Aqueous and lipid nuclear magnetic resonance metabolomic profiles of the earthworm Aporrectodea caliginosa show potential as an indicator species for environmental metabolomics.  

PubMed

The common pasture earthworm Aporrectodea caliginosa has often been neglected in environmental metabolomics in favor of species easily bred in the laboratory. The present study assigns aqueous metabolites in A. caliginosa using high-resolution 1- and 2-dimensional nuclear magnetic resonance (NMR) spectroscopy. In total, 51 aqueous metabolites were identified, including typical amino acids (alanine, leucine, asparagine, phenylalanine), sugars (maltose, glucose), the dominant earthworm-specific 2-hexyl-5-ethyl-furansulfonate, and several previously unreported metabolites (oxoglutarate, putrescine). Examining the lesser-known earthworm lipid metabolome showed various lipid fatty acyl chains, cholesterol, and phosphatidylcholine. To briefly test if the NMR metabolomic techniques could differentiate A. caliginosa from different sites, earthworms were collected from 2 adjacent farms. Orthogonal partial least squares discriminant analysis detected metabolomic differences, suggesting the worms from the 2 sites differed in their energy metabolism, as indicated by altered levels of alanine, glutamine, glutamate, malate, fumarate, and lipids. Evidence of greater utilization of lipid energy reserves and onset of protein catabolism was also present. While the precise cause of the metabolomic differences could not be determined, the results show the potential of this species for further environmental metabolomic studies. Environ Toxicol Chem 2014;33:2313-2322. © 2014 SETAC. PMID:24995628

Brown, Jeffrey N; Samuelsson, Linda; Bernardi, Giuliana; Gooneratne, Ravi; Larsson, D G Joakim

2014-10-01

288

The effects of scopolamine and the nootropic drug phenotropil on rat brain neurotransmitter receptors during testing of the conditioned passive avoidance task  

Microsoft Academic Search

We studied the effects of administration of the new nootropic drug phenotropil (N-carbamoylmethyl-4-phenyl-2-pyrrolidone) at a dose of 100 mg\\/kg on the quantitative characteristics of dopamine (DA), serotonin\\u000a (5-HT), glutamate (NMDA), GABA-A (BDZ), and acetylcholine (nACh) receptors in rats using the conditioned passive avoidance\\u000a task (PAT) under normal conditions and during scopolamine-induced amnesia ex vivo. We found that the cholinolytic drug

Yu. Yu. Firstova; D. A. Abaimov; I. G. Kapitsa; T. A. Voronina; G. I. Kovalev

2011-01-01

289

Relations among invasions of non-native earthworms, forest floor habitat, and populations of ground-nesting songbirds in north temperate hardwood forests.  

E-print Network

??In north temperate and boreal North America, European earthworms Lumbricus have invaded previously earthworm-free forests, substantially changing soil structure, removing the litter layer, and reducing… (more)

Loss, Scott R.

2011-01-01

290

Avoiding Computer Viruses.  

ERIC Educational Resources Information Center

The threat of computer sabotage is a real concern to business teachers and others responsible for academic computer facilities. Teachers can minimize the possibility. Eight suggestions for avoiding computer viruses are given. (JOW)

Rowe, Joyce; And Others

1989-01-01

291

Avoidant personality disorder  

MedlinePLUS

Without treatment, a person with avoidant personality disorder may lead a life of near or total isolation. They may go on to develop a second mental health disorder such as substance abuse or a mood disorder such as depression.

292

Avoidable mortality in Lithuania  

Microsoft Academic Search

STUDY OBJECTIVE--The study aimed to analyse avoidable mortality in Lithuania as an index of the quality of health care and to assess trends in avoidable mortality from 1970-90. SETTING AND PARTICIPANTS--All deaths of Lithuanian residents aged between 0 and 64 years between 1970 and 1990 were analysed. MEASUREMENTS AND MAIN RESULTS--Twenty seven per cent of all deaths in this age

A Gaizauskiene; R Gurevicius

1995-01-01

293

Earthworm influence on carbon dioxide and nitrous oxide fluxes from an unfertilized corn agroecosystem  

Microsoft Academic Search

Earthworms modify the soil environment through their feeding, casting, and burrowing activities, which may lead to more decomposition\\u000a and respiration in aerobic microsites and more denitrification in anaerobic microsites. The objective of this study was to\\u000a determine whether earthworms increase CO2 and N2O fluxes from an unfertilized corn agroecosystem. Earthworm populations within field enclosures (2.9 m2) were reduced by repeatedly applying

Alicia B. Speratti; Joann K. Whalen; Philippe Rochette

2007-01-01

294

Earthworm-induced distribution of organic matter in macro-aggregates from differently managed arable fields  

Microsoft Academic Search

To study the influence of soil structure on organic matter decomposition, and the possible role of earthworms therein, aggregates of the size of earthworm casts (3–4.8 mm) were sieved from air-dry soil of three arable fields. Due to different management histories (in terms of manuring and pesticide use), organic matter contents and earthworm population densities varied markedly between the fields.

J. C. Y. Marinissen; S. I. Hillenaar

1997-01-01

295

The Meek Shall Inherit the Burrow: Feedback in Earthworm Soil Modification  

Microsoft Academic Search

\\u000a From its beginnings, the hallmark of earthworm biology has been a strong emphasis on the study of organism–environment interaction.\\u000a Thereby the radical effects that the earthworms can have in soils have become amply documented. It seems that much less is\\u000a known about how earthworm individuals and populations themselves are affected by their own soil engineering, although various\\u000a feedbacks are conceivable.

Visa Nuutinen

296

Endogeic earthworms differentially influence bacterial communities associated with different soil aggregate size fractions  

Microsoft Academic Search

Endogeic earthworm activities can strongly influence soil structure. Although soil microorganisms are thought to be central to earthworm-facilitated aggregate formation, how and where within the soil matrix earthworm-facilitated influences on soil microbial communities are manifested is poorly defined. In this study we used 16S rRNA gene-based terminal restriction fragment polymorphism (T-RFLP) analyses to examine bacterial communities associated with different aggregate

Daniel L. Mummey; Matthias C. Rillig; Johan Six

2006-01-01

297

Movement of N from decomposing earthworm tissue to soil, microbial and plant N pools  

Microsoft Academic Search

A microcosm experiment was made to determine the fate of nitrogen released from 15N-labelled decomposing earthworms (Lumbricus terrestris) in soil in the presence or absence of ryegrass seedlings (Lolium perenne). Earthworm tissue (2.0% 15N atom enriched) was added to each microcosm. Nitrogen movement from earthworm tissue to soil N [mineral N (NH4-N+NO3-N), dissolved organic N (DON) and organic N], microbial

Joann K. Whalen; Robert W. Parmelee; David A. McCartney; Jessica L. Vanarsdale

1999-01-01

298

Earthworm populations and species distributions under no-till and conventional tillage in Indiana and Illinois  

Microsoft Academic Search

Earthworms often play an important role in maintaining or improving soil physical conditions, and earthworm populations often increase under reduced tillage systems. The objective of our study was to determine earthworm populations and species distributions under long-term no-till vs conventional tillage on a variety of soil types in the states of Indiana and Illinois, U.S.A. Fourteen paired sites were located

Eileen J. Kladivko; Neela M. Akhouri; Glenn Weesies

1997-01-01

299

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

PubMed

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

Szederjesi, Tímea; Pavlí?ek, Tomás; Co?kun, Yüksel; Csuzdi, Csaba

2014-01-01

300

Population dynamics of earthworm communities in corn agroecosystems receiving organic or inorganic fertilizer amendments  

Microsoft Academic Search

The dynamics of earthworm populations were investigated in continuously-cropped, conventional disk-tilled corn agroecosystems\\u000a which had received annual long-term (6 years) amendments of either manure or inorganic fertilizer. Earthworm populations were\\u000a sampled at approximately monthly intervals during the autumn of 1994 and spring and autumn of 1995 and 1996. The dominant\\u000a earthworm species were Lumbricus terrestris L. and Aporrectodea tuberculata (Eisen),

J. K. Whalen; R. W. Parmelee; C. A. Edwards

1998-01-01

301

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

PubMed

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 ?g/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

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

2012-01-17

302

Reactive Collision Avoidance Algorithm  

NASA Technical Reports Server (NTRS)

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.

Scharf, Daniel; Acikmese, Behcet; Ploen, Scott; Hadaegh, Fred

2010-01-01

303

Received 28 Apr 2013 | Accepted 9 Sep 2013 | Published 15 Oct 2013 Earthworms facilitate carbon sequestration through  

E-print Network

carbon sequestration through unequal amplification of carbon stabilization compared with mineralization 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

Neher, Deborah A.

304

Elimination kinetic model for organic chemicals in earthworms.  

PubMed

Mechanistic understanding of bioaccumulation in different organisms and environments should take into account the influence of organism and chemical depending factors on the uptake and elimination kinetics of chemicals. Lipophilicity, metabolism, sorption (bioavailability) and biodegradation of chemicals are among the important factors that may significantly affect the bioaccumulation process in soil organisms. This study attempts to model elimination kinetics of organic chemicals in earthworms by accounting for the effects of both chemical and biological properties, including metabolism. The modeling approach that has been developed is based on the concept for simulating metabolism used in the BCF base-line model developed for predicting bioaccumulation in fish. Metabolism was explicitly accounted for by making use of the TIMES engine for simulation of metabolism and a set of principal transformations. Kinetic characteristics of transformations were estimated on the basis of observed kinetics data for the elimination of organic chemicals from earthworms. PMID:20185163

Dimitrova, N; Dimitrov, S; Georgieva, D; Van Gestel, C A M; Hankard, P; Spurgeon, D; Li, H; Mekenyan, O

2010-08-15

305

Using Flow Cytometry to Measure Phagocytic Uptake in Earthworms†  

PubMed Central

This laboratory module familiarizes students with flow cytometry while acquiring quantitative reasoning skills during data analysis. Leukocytes, also known as coelomocytes (including hyaline and granular amoebocytes, and chloragocytes), from Eisenia hortensis (earthworms) are isolated from the coelomic cavity and used for phagocytosis of fluorescent Escherichia coli. Students learn how to set up in vitro cellular assays and become familiar with theoretical principles of flow cytometry. Histograms based on fluorescence and scatter properties combined with gating options permit students to restrict their analyses to particular subsets of coelomocytes when measuring phagocytosis, a fundamentally important innate immune mechanism used in earthworms. Statistical analysis of data is included in laboratory reports which serve as the primary assessment instrument. PMID:23653715

Fuller-Espie, Sheryl L.

2010-01-01

306

Influence of mineral soil on the palatability of organic matter for lumbricid earthworms: A simple food preference study  

Microsoft Academic Search

The food-preference behaviour of earthworms was examined in order to develop earthworm feeds which might act as a microbial carrier in earthworm-mediated dispersal of beneficial microorganisms in soil. A circular choice chamber containing 18 feeding stations was used to assess the food-type preference of four earthworm species (Aporrectodea caliginosa, A. longa, Lumbricus rubellus, L. terrestris). Representatives of each species were

Bernard M. Doube; Olaf Schmidt; Ken Killham; Ray Correll

1997-01-01

307

Contribution of ecotoxicological tests in the evaluation of soil bioremediation efficiency  

E-print Network

was evaluated using chemical and biological analyses. Experiments were carried out in microcosms contaminated toxicity to earthworms and inhibition of growth of barley roots were selected, from previous work, äs-1), - acute toxicity to the earthworm Eisenia fetida (ISO 11268-1). Both tests were carried out on 100 % soil

Paris-Sud XI, Université de

308

Earthworm-produced calcite granules: A new terrestrial palaeothermometer?  

NASA Astrophysics Data System (ADS)

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.

Versteegh, Emma A. A.; Black, Stuart; Canti, Matthew G.; Hodson, Mark E.

2013-12-01

309

Short-term stabilization of grape marc through earthworms.  

PubMed

The winery industry generates vast amounts of organic waste during the various stages of wine production. Among the possible methodological alternatives available for its treatment, vermicomposting is one of the best-known processes for the biological stabilization of solid organic wastes by transforming them into safer and more stabilized materials suitable for application to soil. In this study we carried out a mesocosm experiment to evaluate the effectiveness of the active phase of vermicomposting for the stabilization of grape marc, an enriched lignocellulosic by-product obtained after the grape crushing and pressing stages in wine production. For this we analysed the chemical, biochemical and microbiological properties of the product resulting from this phase, in comparison with those in a control treatment. Earthworm activity reduced the abundance of both bacterial and fungal PLFA biomarkers. Decreases in microbial activity and in protease and cellulase activities were also attributed to the presence of earthworms. The differences in microbial communities were accompanied by a reduction in the labile C pool and the cellulose content. These results indicate that earthworms played a key role in the stabilization of the grape marc in the short-term, via its effects on organic matter decomposition and microbial biomass and activity. PMID:21277083

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

2011-03-15

310

Integration of Weather Avoidance and Traffic Separation  

NASA Technical Reports Server (NTRS)

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

Consiglio, Maria C.; Chamberlain, James P.; Wilson, Sara R.

2011-01-01

311

Earthworm Aporrectodea trapezoides had no effect on the dispersal of a vesicular-arbuscular mycorrhizal fungi, Glomus intraradices  

Microsoft Academic Search

We investigated the interactions between earthworms and vesicular-arbuscular (VA) mycorrhizal fungi. The effects of earthworms (Aporrectodea trapezoides) at three densities, on the initiation of mycorrhizal colonization of roots of Trifolium subterraneum L. were examined in Experiment 1. An increasing density of earthworms was associated with a decrease in proportional colonization of the roots by mycorrhizal fungi, with a significant difference

G. S. Pattinson; S. E. Smith; B. M. Doube

1997-01-01

312

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

Microsoft Academic Search

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

Claus Svendsen

1996-01-01

313

Tolerance to Zinc in Populations of the Earthworm Lumbricus rubellus from Uncontaminated and Metal-Contaminated Ecosystems  

E-print Network

Tolerance to Zinc in Populations of the Earthworm Lumbricus rubellus from Uncontaminated and Metal characteristics (Posthuma et al. 1992, 1993). For earthworms, published studies have so far failed to find clear tolerance traits. This is in spite of the fact that earthworm populations can persist in soils containing

Hopkin, Steve

314

Impacts of elevated CO2 and O3 on aspen leaf litter chemistry and earthworm and springtail productivity  

E-print Network

Impacts of elevated CO2 and O3 on aspen leaf litter chemistry and earthworm and springtail dioxide Collembola Decomposition Earthworm Growth Leaf litter Ozone Soil a b s t r a c t Human alteration and ozone on aspen (Populus tremuloides) leaf litter chemistry, earthworm (Lumbricus terrestris) individual

315

Avoiding Sophomore Jinx.  

ERIC Educational Resources Information Center

After the first year, new superintendents should take care to avoid the "sophomore jinx" by communicating effectively with the board president every week and with board members before meetings. Public engagement is also an integral part of a superintendent's job. (MLF)

Fitzpatrick, James

2002-01-01

316

Relative Complexity: Beyond Avoidance.  

ERIC Educational Resources Information Center

This paper discusses two influential studies on relative clauses (RC), and addresses the development of relative clauses in the interlanguage of advanced Chinese English-as-a-Second-Language speakers in light of the theory of Accessibility Hierarchy (AH). As the two theories predict, avoidance of RCs is typically found with oblique and genitive…

Yip, Virginia; Matthews, Stephen

1991-01-01

317

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)

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.

Teverovsky, Alexander

2011-01-01

318

Competition between invasive earthworms ( Amynthas corticis, Megascolecidae) and native North American millipedes ( Pseudopolydesmus erasus, Polydesmidae): Effects on carbon cycling and soil structure  

Microsoft Academic Search

Invasive earthworms can have significant impacts on C dynamics through their feeding, burrowing, and casting activities, including the protection of C in microaggregates and alteration of soil respiration. European earthworm invasion is known to affect soil micro- and mesofauna, but little is known about impacts of invasive earthworms on other soil macrofauna. Asian earthworms (Amynthas spp.) are increasingly being reported

Bruce A. Snyder; Bas Boots; Paul F. Hendrix

2009-01-01

319

Earthworm and enchytraeid activity under different arable farming systems, as exemplified by biogenic structures  

E-print Network

specimens per m 2 ), and highest under deep-ploughing (67 specimen per m 2 ), the reverse effect being of agriculture over the last four decades, deterioration of soil structure and increases in soil pollution have and biodiversity of soil fauna, especially earthworms and enchytraeids (Zwart and Brussaard, 1991). Earthworms

Boyer, Edmond

320

Marking earthworms for release–recapture studies using the trace element rubidium  

Microsoft Academic Search

A classic method to assess animal populations is to mark a population, release them into the wild, and make measurements on individuals that are captured after a period of time. The objective of this study was to determine whether earthworms can assimilate and retain sufficient rubidium (Rb) in their tissues to differentiate marked and unmarked earthworms. Fifty adult and 50

Mostafa Ben Hamou; Aleš Kulhánek; Simon Lacombe; Joann K. Whalen

2007-01-01

321

Patterns Of Litter Disappearance In A Northern Hardwood Forest Invaded By Exotic Earthworms  

Microsoft Academic Search

3 Archbold Biological Station, Lake Placid, Florida 33852 USA Abstract. A field study was conducted to evaluate the effects of exotic earthworm invasions on the rates of leaf litter disappearance in a northern hardwood forest in south- central New York, USA. Specifically, we assessed whether differences in litter quality and the species composition of exotic earthworm communities affected leaf litter

Esteban R. Suárez; Timothy J. Fahey; Joseph B. Yavitt; Peter M. Groffman; Patrick J. Bohlen

2006-01-01

322

EARTHWORMS AND COLLEMBOLA RELATIONSHIPS: EFFECTS2 OF PREDATORY CENTIPEDES AND HUMUS FORMS3  

E-print Network

1 EARTHWORMS AND COLLEMBOLA RELATIONSHIPS: EFFECTS2 OF PREDATORY CENTIPEDES AND HUMUS FORMS3 4-00496576,version1-30Jun2010 Author manuscript, published in "Soil Biology and Biochemistry 37, 3 (2005) 487-495" DOI : 10.1016/j.soilbio.2004.08.011 #12;1 Abstract1 2 Relationships between anecic earthworms

Boyer, Edmond

323

Distribution of Heteromurus nitidus (Hexapoda, Collembola) according to soil acidity: interactions with earthworms and predator pressure.  

E-print Network

with earthworms and predator pressure. Sandrine SALMON and Jean François PONGE Laboratoire d'Ecologie Générale,version1-19Jul2010 Author manuscript, published in "Soil Biology and Biochemistry 31, 8 (1999) 1161) according to soil acidity: interactions with earthworms and predator pressure. Sandrine SALMON and Jean

Paris-Sud XI, Université de

324

Phagocytosis in earthworms: An environmentally acceptable endpoint to assess immunotoxic potential of contaminated soils  

SciTech Connect

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.

Giggleman, M.A.; Fitzpatrick, L.C.; Goven, A.J. [Univ. of North Texas, Denton, TX (United States). Dept. of Biological Sciences; Venables, B.J. [TRAC Labs., Inc., Denton, TX (United States); Callahan, C.A. [Environmental Protection Agency, San Francisco, CA (United States)

1995-12-31

325

Density and biomass of earthworms in forest and herbaceous microecosystems in central New York, North America  

Microsoft Academic Search

We have determined and assessed the earthworm population community structure under different selected microecosystems (i.e. forest ecosystem and herbaceous ecosystem). Samples of earthworms and soil were studied from four sites in Lafayette Forest Experimental Station, State University of New York, College of Environmental Science and Forestry. These sites are the Northern Hardwood forest, Tamarack plantation, Norway spruce and Old Field

Safwat H. Shakir; Daniel L. Dindal

1997-01-01

326

Labeling earthworms uniformly with 13C and 15N: implications for monitoring nutrient fluxes  

Microsoft Academic Search

Stable isotopes hold promise for improving our ability to quantify energy and N released from earthworm populations through metabolic processes and mortality. However, the isotopic labels 13C and 15N must be incorporated uniformly into the structural and labile tissues of earthworms to trace C and N fluxes accurately. We examined the distribution of 13C and 15N in the tissue and

Joann K Whalen; H. Henry Janzen

2002-01-01

327

Regulation of soil structure by geophagous earthworm activities in humid savannas of Côte d'Ivoire  

Microsoft Academic Search

The role of endogeic earthworms in the maintenance of the structure of an African savanna soil has been investigated in a 28-month field experiment. Changes of aggregate size distribution, porosity and aggregate stability were analysed in undisturbed soil monoliths from which earthworms had been removed and which had then been submitted to four treatments: (1) recolonization by natural savanna fauna

E. Blanchart; P. Lavelle; E. Braudeau; Y. Le Bissonnais; C. Valentin

1997-01-01

328

Effects of Earthworm Invasion on Plant Species Richness in Northern Hardwood Forests  

E-print Network

Effects of Earthworm Invasion on Plant Species Richness in Northern Hardwood Forests ANDREW R. HOLDSWORTH, LEE E. FRELICH, AND PETER B. REICH University of Minnesota, Conservation Biology Graduate of non-native earthworms (Lumbricus spp.) into a small number of intensively studied stands of northern

Minnesota, University of

329

Species effects on earthworm density in tropical tree plantations in Hawaii  

Microsoft Academic Search

Tree species differ in the quantity and quality of litter produced, and these differences may significantly affect ecosystem structure and function. I examined the importance of tree species in determining earthworm densities in replicated stands of Eucalyptus saligna Sm. and Albizia falcataria (L.) Fosberg, and in mixed stands (25% albizia and 75% eucalyptus). Mean earthworm densities ranged from 92 m-2

Xiaoming Zou

1993-01-01

330

The heterogeneity of humus profiles and earthworm communities in a virgin beech forest  

E-print Network

and vegetation conditions. Humus profiles and earthworm communities were sampled in April 1992. The biological1 The heterogeneity of humus profiles and earthworm communities in a virgin beech forest J.F. Ponge in the biological reserve of La Tillaie (Fontainebleau Forest, France) were investigated in April 1992. Beech (Fagus

Paris-Sud XI, Université de

331

Contrasted effect of biochar and earthworms on rice growth and resource allocation in different soils  

Microsoft Academic Search

Adding biochar to soils and maintaining high earthworm biomasses are potential ways to increase the fertility of tropical soils and the sustainability of crop production in the spirit of agroecology and ecological engineering. However, a thorough functional assessment of biochar effect on plant growth and resource allocations is so far missing. Moreover, earthworms and biochar increase mineral nutrient availability through

Diana Noguera; Marco Rondón; Kam-Rigne Laossi; Valerio Hoyos; Patrick Lavelle; Maria Helena Cruz de Carvalho; Sébastien Barot

2010-01-01

332

Interaction of the earthworm Diplocardia mississippiensis (Megascolecidae) with microbial and nutrient dynamics in a subtropical Spodosol  

Microsoft Academic Search

Direct and indirect effects of earthworm feeding and activity can alter soil microbial and nutrient dynamics. Little is known about influence of native North American earthworms on these dynamics. We investigated effects of native D. mississippiensis activity on total and soluble C, N and microbial biomass pools in Spodosols from the Apalachicola National Forest in North Florida, USA. Soil native

Sharon. L Lachnicht; Paul F Hendrix

2001-01-01

333

Earthworm effects on crop and weed biomass, and N content in organic and inorganic fertilized agroecosystems  

Microsoft Academic Search

Results are reported from an experiment comparing the effects of earthworm manipulations and agroecosystem fertility treatments on corn (maize, Zea mays) and weed biomass, and on nitrogen content. The experimental design consisted of inorganic (ammonium nitrate) and organic (cover crop and manure) fertility treatments. Within each fertility treatment, earthworm manipulations consisted of ambient, augmented and reduced populations. Both ambient and

B. R. Stinner; D. A. McCartney; J. M. Blair; R. W. Parmelee; M. F. Allen

1997-01-01

334

Earthworm effects on respiratory activity in a dung-soil system  

Microsoft Academic Search

In many pastures earthworms are crucially important in the disappearance of dung pats, as they are the major agent affecting transport of organic material away from the pat. The aim of this study was to examine to what extent this earthworm mediated process could contribute to the microbial respiration in soil below dung. Plastic pots with soil and cattle dung,

Niels Bohse Hendriksen

1997-01-01

335

Earthworm effects on selected physical and chemical properties of soil aggregates  

Microsoft Academic Search

Some physical and chemical properties of 1-to 2-mm aggregates obtained from casts and the burrow-wall material of the earthworm species Lumbricus terrestris, Aporrectodea longa, and Aporrectodea caliginosa were determined in order to show the effects of earthworms on the stabilization of soil aggregates. The results were compared with those of the natural soil from the Ap horizon of a Parabraunerde

H. Zhang; S. Schrader

1993-01-01

336

Detritivorous earthworms directly modify the structure, thus altering the functioning of a microdecomposer food web  

Microsoft Academic Search

Epigeic earthworms are key organisms in fresh organic matter mounds and other hotspots of heterotrophic activity. They turn and ingest the substrate intensively interacting with microorganisms and other soil fauna. By ingesting, digesting and assimilating the surrounding substrate, earthworms could directly modify the microdecomposer community, yet little is known of such direct effects. Here we investigate the direct effects of

Manuel Aira; Luis Sampedro; Fernando Monroy; Jorge Domínguez

2008-01-01

337

Interactions between earthworms and soil protozoa: A trophic component in the soil food web  

Microsoft Academic Search

Earthworms and protozoa are, in terms of biomass, the most important groups of soil fauna in beech forests on limestone in southern Lower Saxonia (Germany). To investigate the effect of high protozoan numbers on earthworm distribution, a multiple choice feeding experiment was set up in fumigated soil, reinoculated with different numbers of naked amoebae, protozoa commonly found in that soil.

Michael Bonkowski; Matthias Schaefer

1997-01-01

338

Toxicity and bioaccumulation of chlorophenols in earthworms, in relation to bioavailability in soil  

Microsoft Academic Search

The acute toxicity of five chlorophenols for two earthworm species was determined in two sandy soils differing in organic matter content and the results were compared with adsorption data. Adsorption increased with increasing organic matter content of the soils, but for tetra- and pentachlorophenol was also influenced by soil pH. Earthworm toxicity was significantly higher in the soil with a

C. A. van Gestel; W. C. Ma

1988-01-01

339

The role of earthworms for assessment of sustainability and as bioindicators  

Microsoft Academic Search

Earthworms, which inhabit soils and litter layers in most landscapes, can offer an important tool to evaluate different environmental transformations and impacts. Agricultural landscapes, urban and industrialized habitats have some earthworms that represent interesting indicators to monitor different contaminations, to assess different farming practices and different landscape structures and transformations. Species number, abundance and biomass can give easily measurable elements.

Maurizio G. Paoletti

1999-01-01

340

Influence of texture and amendments on soil properties and earthworm communities  

Microsoft Academic Search

In Canada, the influence of earthworms on soil is considered particularly important in the Southern regions where agriculture has developed. A field experiment was duplicated on a clay loam and a sandy loam soil in the Saint-Lawrence Valley. Both sites were enriched with urban compost or mineral amendment. The effects of amendments on soil properties and the earthworm community were

E. Lapied; J. Nahmani; G. X. Rousseau

2009-01-01

341

Effects of the presence and community composition of earthworms on microbial community functioning  

Microsoft Academic Search

Earthworms are a major component of many terrestrial ecosystems. By modifying decomposition processes and soil structure, they function as driving factors of the soil microbial community. Using microcosms, we investigated the effects of the presence and community composition of earthworms on the in situ respiratory response of a microbial community to an array of organic substrates including carbohydrates, amino acids,

Stefan Scheu; Natalie Schlitt; Alexei V. Tiunov; John E. Newington; Hefin T. Jones

2002-01-01

342

Potential of two epigeic and two anecic earthworm species in vermicomposting of water hyacinth  

Microsoft Academic Search

The potential of two epigeic species (Eudrilus eugeniae Kinberg, and Perionyx excavatus Perrier) and two anecic species (Lampito mauritii Kinberg and Drawida willsi Michaelson) of earthworms was assessed in terms of efficiency and sustainability of vermicomposting water hyacinth (Eichhornia crassipes, Mart. Solm.). In different vermireactors, each run in duplicate with one of the four species of earthworms, and 75 g

S Gajalakshmi; E. V Ramasamy; S. A Abbasi

2001-01-01

343

INVASION NOTE The wave towards a new steady state: effects of earthworm  

E-print Network

Ecosystem change Á Exotic earthworms Á Forest floor Á Microbial biomass Á Microbial respiration Á Northern hardwood forests Introduction Anthropogenic biotic exchange threatens biodiversity and can compromise engineers that cause a long cascade of ecological effects when they invade previously earthworm-free forests

Minnesota, University of

344

Portable Conduction Velocity Experiments Using Earthworms for the College and High School Neuroscience Teaching Laboratory  

ERIC Educational Resources Information Center

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…

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

2014-01-01

345

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

PubMed

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

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

2013-09-01

346

Avoiding Predation Two Ways to Avoid Getting Eaten  

E-print Network

, and black. #12;3 Avoiding Attack Once Detected Animals that are not dangerous may exhibit mimicry of other animals that are There are two individuals/species Model is always toxic, noxious or dangerous Mimic may1 Avoiding Predation Two Ways to Avoid Getting Eaten Predator avoidance behaviors remove animals

Brown, Christopher A.

347

The effect of earthworms on the fractionation, mobility and bioavailability of Pb, Zn and Cd before and after soil leaching with EDTA  

Microsoft Academic Search

The effect of two ecologically contrasting earthworm species Eisenia fetida (epigeic) and Octolasion tyrtaeum (endogeic) on the fractionation (accessed using sequential extractions), mobility (toxicity characteristic leaching procedure, TCLP) and oral bioavailability (Ruby’s physiologically based extraction test, PBET) of Pb, Zn and Cd was studied before and after soil remediation with soil leaching. Twenty-step leaching, with 2.5mmolkg?1 EDTA used in each

Metka Udovic; Ziva Plavc; Domen Lestan

2007-01-01

348

Effect of the endogeic earthworm Pontoscolex corethrurus on soil chemical characteristics and plant growth in a low-input tropical agroecosystem  

Microsoft Academic Search

Low densities of Pontoscolex corethrurus have been introduced into low-input cropping systems at Yurimaguas (Peru) to test their effects on soil fertility under field conditions for six successive cropping cycles. Earthworm biomass was sustained at 40g m?2 fw (ca. 3 g ash-free dry mass) on the average with peak values of 80 g at harvests 2 and 3 in treatments

B. Pashanasi; P. Lavelle; J. Alegre; F. Charpentier

1996-01-01

349

870 VOLUME 24 NUMBER 8 AUGUST 2006 NATURE BIOTECHNOLOGY Another strategy is to avoid placing all your eggs in the testing labora-  

E-print Network

opportunistically into the biological defense market to develop anthrax and other biohazard detection systems for there is a premium on a rapid response. Encouraging adoption of a test is only part of the battle, however. The other

Cai, Long

350

ECONOMICS OF AVOIDING DEFORESTATION  

E-print Network

Deforestation is estimated to cause about one quarter of anthropogenic carbon emissions. Only late, in 2005, Parties to the United Nations Framework Convention for Climate Change decided to start exploring approaches to reduce emissions from this major source. We carried out a global analysis of the potential effects of financial mechanisms to avoid deforestation. Avoiding deforestation is a low cost option that could have considerable leverage in mitigating climate change. Our model results indicate that a 50 % reduction of carbon emissions from deforestation over the next 20 years would require financial resources of some US$33 bn per year. Expectations that financial flows through international climate policy mechanisms would provide a golden opportunity to turn around a 20 year history of gridlock and indecision in international fora addressing deforestation, however, appear inflated.

unknown authors

2006-01-01

351

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

PubMed

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

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

2015-01-01

352

Fluoride accumulation in different earthworm species near an industrial emission source in southern Germany  

SciTech Connect

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.

Vogel, J.; Ottow, J.C.G. (Justus-Liebig Univ., Giessen (Germany))

1991-10-01

353

Avoiding manuscript mistakes.  

PubMed

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

Grindstaff, Terry L; Saliba, Susan A

2012-10-01

354

Reduction of total coliform numbers during vermicomposting is caused by short-term direct effects of earthworms on microorganisms and depends on the dose of application of pig slurry  

Microsoft Academic Search

During vermicomposting of organic waste, the interactions between epigeic earthworms and the detrital microbial community lead to decreases in the abundance of some potentially pathogenic microorganisms. Despite its importance, little is known about the mechanisms involved and the factors that affect the intensity of this effect. In the present study, we carried out three experiments to test the effect of

Fernando Monroy; Manuel Aira; Jorge Domínguez

2009-01-01

355

A field screening method using earthworms (Eisenia foetida andrei) to evaluate contaminated soils  

SciTech Connect

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.

Wilborn, D.C.; Bollman, M.A.; Gillett, C.S.; Ott, S.L.; Linder, G.L. [Takena Ecological Services, Inc., Corvallis, OR (United States)

1997-09-01

356

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

PubMed

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

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

2013-01-01

357

Human Hippocampus Arbitrates Approach-Avoidance Conflict  

PubMed Central

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

Bach, Dominik R.; Guitart-Masip, Marc; Packard, Pau A.; Miro, Julia; Falip, Merce; Fuentemilla, Lluis; Dolan, Raymond J.

2014-01-01

358

Earthworm survival and behavior results from a Clark Fork River Superfund site: Grant-Kohrs Ranch N.H.S., Montana  

SciTech Connect

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.

Rader, B.R.; Nimmo, D.R.; Chapman, P.L. [Colorado State Univ., Fort Collins, CO (United States)

1995-12-31

359

Earthworm ? 13 C and ? 15 N analyses suggest that putative functional classifications of earthworms are site-specific and may also indicate habitat diversity  

Microsoft Academic Search

Natural abundances of the stable isotope pairs 13C\\/12C and 15N\\/14N (?13C and ?15N) were measured from earthworms sampled from six sites with contrasting habitats (deciduous and coniferous woodland, arable and permanent pasture). Knowledge about the function of earthworms is important to the understanding of their ecology. The hypothesis, that endogeic (primarily soil and organic matter feeders) and epigeic (surface litter

Roy Neilson; Brian Boag; Michael Smith

2000-01-01

360

Potential impacts of invasive European earthworms and soil moisture on herbaceous species richness within the Ojibwa Red Lake Reservation  

NASA Astrophysics Data System (ADS)

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.

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

361

The Perceived-Threat Behavioral Approach Test (PT-BAT): Measuring Avoidance in High-, Mid-, and Low-Spider-Fearful Participants  

ERIC Educational Resources Information Center

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…

Cochrane, Andy; Barnes-Holmes, Dermot; Barnes-Holmes, Yvonne

2008-01-01

362

Avoidance response of rainbow trout to phenol  

SciTech Connect

An eight-concentration intermittent-flow proportional diluter was modified to provide continuous flow to four separate avoidance chambers and used to test the avoidance response to phenol of rainbow trout (Salmo gairdneri) in three separate 5-day tests. When single fish had been acclimated for 24 h, a flow of phenol was initiated on one side of each avoidance chamber and well water was started on the other. After 48 h the phenol and well water sides were switched, and the experiment was continued for another 48 h; the positions of the fish in the chambers were monitored photographically throughout the test. Results of tests with 12 rainbow trout indicated that the threshold avoidance level was between 6.5 and 3.2 mg/L phenol, which was between 58 and 73% of the phenol 96-h LC50 for rainbow trout. Since long-term effects for rainbow trout exposed to phenol have been documented at concentrations as low as 0.2 mg/L, the avoidance tests were not nearly as sensitive as toxicity tests with embryos and larvae.

DeGraeve, G.M.

1982-04-01

363

Aggregate formation and soil carbon sequestration by earthworms at the ORNL FACE experiment  

NASA Astrophysics Data System (ADS)

Earthworms have an important role in soil carbon sequestration, but their contribution to carbon sequestration in soils exposed to elevated atmospheric CO2 concentrations has been largely overlooked. Previous studies at the Oak Ridge National Laboratory Free Air CO2 Experiment (ORNL FACE) site showed that the formation of soil aggregates is a key mechanism for soil carbon sequestration. We did a microcosm experiment to quantify earthworm-mediated aggregate formation and compare between two earthworm species with different feeding habits (endogeic vs. epi-edogeic). In addition, we wanted to identify the carbon source (soil, leaf litter or root litter) within aggregates formed by earthworms. We used 13C-depleted soil and 15N-enriched sweetgum (Liquidambar styraciflua) leaf and root litter collected from the ORNL FACE site to assess soil aggregate formation of the native, endogeic earthworm Diplocardia sp. and European, epi-endogeic earthworm Lumbricus rubellus. Both earthworm species are present at the ORNL FACE site. We crushed, sieved (< 250 ?m) soil and prepared four treatments: (I) soil only; (II) soil and plant material; (III) soil, plant material and Diplocardia sp.; (IV) soil, plant material and L. rubellus. All treatments were at 30% water content and temperature was maintained at 20°C. The incubation period lasted 26 days. We measured aggregate size distribution, total aggregate carbon content and 13C and 15N to elucidate aggregate carbon source. Newly formed soil macroaggregates (> 250 ?m) were higher in treatments with earthworms (III and IV) than in treatments without earthworms (I and II) (p = 0.02). Within macroaggregates, most of the carbon was soil-derived. Leaf and root-derived carbon was found in treatment IV only. Our results suggest that earthworms at the ORNL FACE site directly contribute to the formation of soil aggregates, thus contributing to soil carbon sequestration. Carbon source within macroaggregates correspond with earthworm feeding habits, with endogeic earthworms (Diplocardia sp.) feeding mostly on mineral soil and epi-endogeic earthworm (L. rubellus) feeding on both plant residues and soil organic matter.

Sanchez-de Leon, Y.; Gonzalez-Meler, M. A.; Lugo-Perez, J.; Wise, D. H.; Jastrow, J. D.

2012-12-01

364

Involvement of the cholinergic system of CA1 on harmane-induced amnesia in the step-down passive avoidance test.  

PubMed

?-carboline alkaloids such as harmane (HA) are naturally present in the human food chain. They are derived from the plant Peganum harmala and have many cognitive effects. In the present study, effects of the nicotinic system of the dorsal hippocampus (CA1) on HA-induced amnesia and exploratory behaviors were examined. One-trial step-down and hole-board paradigms were used to assess memory retention and exploratory behaviors in adult male mice. Pre-training (15?mg/kg) but not pre-testing intraperitoneal (i.p.) administration of HA decreased memory formation but did not alter exploratory behaviors. Moreover, pre-testing administration of nicotine (0.5?µg/mouse, intra-CA1) decreased memory retrieval, but induced anxiogenic-like behaviors. On the other hand, pre-test intra-CA1 injection of ineffective doses of nicotine (0.1 and 0.25?µg/mouse) fully reversed HA-induced impairment of memory after pre-training injection of HA (15?mg/kg, i.p.) which did not alter exploratory behaviors. Furthermore, pre-testing administration of mecamylamine (0.5, 1 and 2?µg/mouse, intra-CA1) did not alter memory retrieval but fully reversed HA-induced impairment of memory after pre-training injection of HA (15?mg/kg, i.p.) which had no effect on exploratory behaviors. In conclusion, the present findings suggest the involvement of the nicotinic cholinergic system in the HA-induced impairment of memory formation. PMID:21965190

Nasehi, Mohammad; Sharifi, Shahrbano; Zarrindast, Mohammad Reza

2012-08-01

365

Physiological and behavioural effects of imidacloprid on two ecologically relevant earthworm species (Lumbricus terrestris and Aporrectodea caliginosa).  

PubMed

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

Dittbrenner, Nils; Triebskorn, Rita; Moser, Isabelle; Capowiez, Yvan

2010-11-01

366

Interactions between organic matter and mineral surfaces along an earthworm invasion gradient in a sugar maple forest of Minnesota  

NASA Astrophysics Data System (ADS)

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.

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

2012-12-01

367

Avoidable waste management costs  

SciTech Connect

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.

Hsu, K.; Burns, M.; Priebe, S.; Robinson, P.

1995-01-01

368

Concentration of cadmium in Coturnix quail fed earthworms  

SciTech Connect

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.

Stoewsand, G.S.; Bache, C.A.; Gutenmann, W.H.; Lisk, D.J.

1986-01-01

369

Polychlorinated biphenyls (PCBs) depress allogeneic natural cytotoxicity by earthworm coelomocytes  

SciTech Connect

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.

Suzuki, M.M.; Cooper, E.L. [Univ. of California, Los Angeles, CA (United States). Lab. of Comparative Immunology; Eyambe, G.S.; Goven, A.J.; Fitzpatrick, L.C. [Univ. of North Texas, Denton, TX (United States). Dept. of Biological Sciences; Venables, B.J. [Univ. of North Texas, Denton, TX (United States). Dept. of Biological Sciences]|[TRAC Labs., Denton, TX (United States)

1995-10-01

370

Effects of heavy metals on the litter consumption by the earthworm Lumbricus rubellus in field soils  

USGS Publications Warehouse

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.

Hobbelen, P. H. F.; Koolhaas, J. E.; Van Gestel, C. A. M.

2006-01-01

371

Earthworm populations as related to woodcock habitat usage in Central Maine  

USGS Publications Warehouse

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.

Reynolds, J.W.; Krohn, W.B.; Hordan, G.A.

1977-01-01

372

Effect of enzyme producing microorganisms on the biomass of epigeic earthworms (eisenia fetida) in vermicompost.  

PubMed

We analyzed the bacterial community structure of the intestines of earthworms and determined the effect of enzyme producing microorganisms on the biomass of earthworms in vermicompost. Fifty-seven bacterial 16S rDNA clones were identified in the intestines of earthworms by using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analysis. Entomoplasma somnilux and Bacillus licheniformis were the dominant microorganisms; other strains included Aeromonas, Bacillus, Clostridium, Ferrimonas, and uncultured bacteria. Among these strains, Photobacterium ganghwense, Aeromonas hydrophila, and Paenibacillus motobuensis were enzyme-producing microorganisms. In the mixtures that were inoculated with pure cultures of A. hydrophila WA40 and P. motobuensis WN9, the highest survival rate was 100% and the average number of earthworms, young earthworms, and cocoons were 10, 4.00-4.33, and 3.00-3.33, respectively. In addition, P. motobuensis WN9 increased the growth of earthworms and production of casts in the vermicompost. These results show that earthworms and microorganisms have a symbiotic relationship. PMID:21421302

Hong, Sung Wook; Lee, Ju Sam; Chung, Kun Sub

2011-05-01

373

Experiential Avoidance and Post-Traumatic Stress Disorder  

Microsoft Academic Search

Does experiential avoidance predict PTSD severity among rape survivors? We tested a hypothesized model where causal attributions, cognitive schemas, and memory characteristics mediated the relationship between experiential avoidance and PTSD. Experiential avoidance was measured as a cognitive coping strategy; women scoring high on this measure did not try to integrate or make meaning of their rape experiences, but rather attempted

Laura E. Boeschen; Mary P. Koss; Aurelio Jose Figueredo; James A. Coan

2001-01-01

374

Reactive Collision Avoidance for Unmanned Aerial Vehicles Using Doppler Radar  

Microsoft Academic Search

Summary. Research into reactive collision avoidance for unmanned aerial vehicles has been conducted on unmanned terrestrial and mini aerial vehicles utilising active Doppler radar obstacle detection sensors. Flight tests conducted by flying a mini UAV at an obstacle have confirmed that a simple reactive collision avoidance al- gorithm enables aerial vehicles to autonomously avoid obstacles. This builds upon simulation work

Andrew Viquerat; Lachlan Blackhall; Alistair Reid; Salah Sukkarieh; Graham Brooker

2007-01-01

375

Geochemistry and Chemical Weathering in Soils along an Earthworm Invasion Gradient  

NASA Astrophysics Data System (ADS)

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.

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

2010-12-01

376

Mapping spatial distribution of preferential flow using earthworms distribution models in combination with tracer infiltration patterns  

NASA Astrophysics Data System (ADS)

Slow matrix flow and rapid by-pass, i.e. preferential flow, result in a large variability of flow in the topsoil. The spatiotemporal infiltration variability in the topsoil strongly determines the distribution of precipitation water to surface runoff, soil moisture storage and rapid percolation to groundwater. Measurement of quantitative indicators for preferential flow and conversion to input parameters for hydrological modelling remain major difficulties in modelling the impact of preferential flow. Preferential flow often takes place along macropores of biological origin, such as earthworm burrows and root channels. There are three different earthworm types which have different burrowing patterns. These result in different preferential infiltration patterns, varying from rapid deep vertical infiltration to a stronger diffuse distribution of water and solutes in the upper soil layers. Thus the spatial distribution of different ecological earthworm types can help us to understand the spatial variability in preferential infiltration patterns. Geometrical properties of macropores however have in the past proven insufficient to predict preferential flow rates as different numbers and sizes of pores may be hydrologically effective under different conditions. Therefore it is important to link the spatiotemporal distribution of earthworms to the effective preferential flow patterns. This study is part of the Biopore project, which has as final aim to link spatiotemporal earthworm distribution models with a preferential flow model to obtain an integrated eco-hydrological model. Previous research showed that earthworm presence was the main cause of preferential flow in the study area, the Weiherbach Catchment (Baden-Württemberg, Germany). For this catchment spatiotemporal distribution patterns of earthworms were modelled using soil properties (organic matter content, texture, soil moisture), and topography (slope, elevation) as predictors for earthworm occurrence, abundance and biomass. The results of the spatiotemporal distribution patterns of earthworms are used as indicator for potential spatiotemporal occurrence of preferential flow and are linked to tracer infiltration patterns to obtain information on spatial distribution of effective preferential flow.

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

2010-05-01

377

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

NASA Astrophysics Data System (ADS)

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.

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

2011-11-01

378

Metallothionein gene expression differs in earthworm populations with different exposure history.  

PubMed

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

Mustonen, M; Haimi, J; Väisänen, A; Knott, K E

2014-11-01

379

Measuring Experiential Avoidance in Adults: The Avoidance and Fusion Questionnaire  

ERIC Educational Resources Information Center

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…

Schmalz, Jonathan E.; Murrell, Amy R.

2010-01-01

380

Soil Chemical Weathering and Nutrient Budgets along an Earthworm Invasion Chronosequence in a Northern Minnesota Forest  

NASA Astrophysics Data System (ADS)

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.

Resner, K. E.; Yoo, K.; Sebestyen, S. D.; Aufdenkampe, A. K.; Lyttle, A.; Weinman, B. A.; Blum, A.; Hale, C. M.

2011-12-01

381

Abandoned coal mining sites: using ecotoxicological tests to support an industrial organic sludge amendment.  

PubMed

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

Chiochetta, Claudete G; Radetski, Marilice R; Corrêa, Albertina X R; Tischer, Vinícius; Tiepo, Erasmo N; Radetski, Claudemir M

2013-11-01

382

Scaling of the hydrostatic skeleton in the earthworm Lumbricus terrestris.  

PubMed

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

Kurth, Jessica A; Kier, William M

2014-06-01

383

Earthworm coelomocytes as nanoscavenger of ZnO NPs.  

PubMed

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

Gupta, Shruti; Kushwah, Tanuja; Yadav, Shweta

2014-01-01

384

Earthworm coelomocytes as nanoscavenger of ZnO NPs  

PubMed Central

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

2014-01-01

385

Tax evasion and avoidance typologies  

Microsoft Academic Search

Purpose – The purpose of this paper is to explore tax evasion and avoidance typologies with a view to understanding how they work and the implications for those who handle the wealth of others. Design\\/methodology\\/approach – American, Canadian and UK cases of tax avoidance and tax evasion are studied. Findings – Structuring transactions to avoid or minimize taxes is highly

Jeffrey Simser

2008-01-01

386

Redundant Robot Can Avoid Obstacles  

NASA Technical Reports Server (NTRS)

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.

Homayoun, Seraji; Colbaugh, Richard; Glass, Kristin

1991-01-01

387

Avoidance Learning TIAGO V. MAIA  

E-print Network

Avoidance Learning TIAGO V. MAIA Department of Psychiatry, Columbia University and New York State Psychiatric Institute, New York, NY, USA Synonyms Learning to avoid aversive outcomes Definition Learning that would otherwise occur. Avoidance learning in that context consists of learning to perform

388

Value contamination avoidance devices  

NASA Technical Reports Server (NTRS)

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.

Endicott, D. L.

1975-01-01

389

Incorporation of strontium in earthworm-secreted calcium carbonate granules produced in strontium-amended and strontium-bearing soil  

NASA Astrophysics Data System (ADS)

This paper investigates the incorporation of Sr into biomineralized calcium carbonate granules secreted by the earthworm Lumbricus terrestris. Experiments were conducted using an agricultural soil amended with Sr(NO3)2 to give concentrations in the range 50-500 mg kg-1 Sr and a naturally Sr-rich, Celestine-bearing soil containing up to 11 000 mg kg-1 Sr. Granule production rates were in the range 0.26-2.3 mgCaCO3 earthworm-1 day-1; they showed no relationship with soil or soil solution Sr concentration but decreased with decreasing pH. Strong relationships exist (r2 ? 0.8, p ? 0.01) between the Sr concentrations and Sr/Ca ratios of the granules and those of the soil, soil solution and earthworms. The highest bulk Sr concentration we recorded in the calcium carbonate granules was 5.1 wt.% Sr whilst electron microprobe analysis recorded spot concentrations of up to 4.3 wt.% Sr. X-ray diffraction and X-ray absorption spectroscopy indicate that the majority of the calcium carbonate is present as Sr-bearing calcite with trace amounts of Sr-bearing vaterite also being present. The granules produced in the Sr-amended soils concentrated Sr relative to Ca from the bulk soil and the earthworms. This suggests that earthworm secreted calcium carbonate may be significant in the cycling of 90Sr released into soils via nuclear accidents or leakage from nuclear waste storage facilities.

Brinza, Loredana; Quinn, Paul D.; Schofield, Paul F.; Mosselmans, J. Frederick W.; Hodson, Mark E.

2013-07-01

390

Effects of polyethyleneimine-mediated functionalization of multi-walled carbon nanotubes on earthworm bioaccumulation and sorption by soils.  

PubMed

Carbon nanotubes (CNTs) are often modified for different intended potential applications to enhance their aqueous stability or change properties such as surface charge. Such changes may also profoundly impact their environmental behaviors. Herein, we report the effects of modifying (14)C-labeled multiwalled carbon nanotubes (MWCNTs) with polyetheyleneimine (PEI) surface coatings to render them more stable in solution and to give them positive, negative, or neutral surface charges. These carbon nanotubes were used to test their sorption by soils and uptake and elimination behaviors by earthworms. Sorption results indicate nearly linear sorption isotherms for regular MWCNTs and nonlinear isotherms for modified MWCNTs, indicating that the PEI coatings influenced MWCNT interactions with soils. Nevertheless, there were minimal differences in the sorption results among the different soils for each type of nanotube despite differences in the soil organic carbon and cation exchange capacities. Differences in uptake behaviors by earthworms were not apparent among different types of PEI-MWCNTs and MWCNTs with limited absorption into organism tissues consistently observed. Elimination patterns were well fit with an exponential decay model suggesting that the worms can readily eliminate any accumulated MWCNTs. PMID:21434629

Petersen, Elijah J; Pinto, Roger A; Zhang, Liwen; Huang, Qingguo; Landrum, Peter F; Weber, Walter J

2011-04-15

391

Interactions between plant species and earthworm casts in a calcareous grassland under elevated CO{sub 2}  

SciTech Connect

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}.

Zaller, J.G.; Arnone, J.A. III [Univ. Basel (Switzerland). Botanisches Inst.

1999-04-01

392

Is carbon sequestration on post mining sites driven by earthworm activity?  

NASA Astrophysics Data System (ADS)

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.

Frouz, J.; Pizl, V.

2009-04-01

393

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...

394

Toxicological responses of earthworm (Eisenia fetida) exposed to metal-contaminated soils.  

PubMed

The aim of this study was to evaluate the toxicological responses of earthworm (Eisenia fetida) induced by field-contaminated, metal-polluted soils. Biochemical responses and DNA damage of earthworm exposed to two multi-metal-contaminated soils in a steel industry park and a natural reference soil in Zijin Mountain for 2, 7, 14, and 28 days were studied. Results showed that three enzyme activities, including superoxide dismutase (SOD), acetylcholinesterase (AChE), and cellulase, in earthworm in metal-contaminated soils were significantly different from those of the reference soil. Cellulase and AChE were more sensitive than SOD to soil contamination. The Olive tail moment of the comet assay after 2-day exposure increased 56.5 and 552.0 % in two contaminated soils, respectively, compared to the reference soil. Our findings show that cellulase and DNA damage levels can be used as potential biomarkers for exposure of earthworm to metal-polluted soils. PMID:23589267

Zheng, Kai; Liu, ZhengTao; Li, YaJie; Cui, YiBin; Li, Mei

2013-12-01

395

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

PubMed

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

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

396

Verminephrobacter eiseniae type IV pili and flagella are required to colonize earthworm nephridia  

PubMed Central

The bacterial symbiont Verminephrobacter eiseniae colonizes nephridia, the excretory organs, of the lumbricid earthworm Eisenia fetida. E. fetida transfers V. eisenia into the egg capsule albumin during capsule formation and V. eiseniae cells migrate into the earthworm nephridia during embryogenesis, where they bind and persist. In order to characterize the mechanistic basis of selective tissue colonization, methods for site-directed mutagenesis and colonization competence were developed and used to evaluate the consequences of individual gene disruptions. Using these newly developed tools, two distinct modes of bacterial motility were shown to be required for V. eiseniae colonization of nascent earthworm nephridia. Flagella and type IV pili mutants lacked motility in culture and were not able to colonize embryonic earthworms, indicating that both twitching and flagellar motility are required for entrance into the nephridia. PMID:22170422

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

2012-01-01

397

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

PubMed

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

Zaller, Johann G; Heigl, Florian; Ruess, Liliane; Grabmaier, Andrea

2014-01-01

398

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 ...

399

Recent advances in the Lesser Antilles observatoriesRecent advances in the Lesser Antilles observatories Part 1 : Seismic Data Acquisition Design based on EarthWorm andPart 1 : Seismic Data Acquisition Design based on EarthWorm and  

E-print Network

observatories Part 1 : Seismic Data Acquisition Design based on EarthWorm andPart 1 : Seismic Data Acquisition Design based on EarthWorm and SeisComPSeisComP Jean-Marie SAUREL (2,1), Frédéric RANDRIAMORA (3 observatories community : EarthWorm and SeisComP. The first is renowned for its ability to process real time

Beauducel, François

400

Determination of multi-walled carbon nanotube bioaccumulation in earthworms measured by a microwave-based detection technique.  

PubMed

Reliable quantification techniques for carbon nanotubes (CNTs) are limited. In this study, a new procedure was developed for quantifying multi-walled carbon nanotubes (MWNTs) in earthworms (Eisenia fetida) based on freeze drying and microwave-induced heating. Specifically, earthworms were first processed into a powder by freeze drying. Then, samples were measured by utilizing 10 s exposure to 30 W microwave power. This method showed the potential to quantitatively measure MWNTs in earthworms at low concentrations (~0.1 ?g in 20 mg of earthworm). Also, a simple MWNT bioaccumulation study in earthworms indicated a low bioaccumulation factor of 0.015±0.004. With an appropriate sample processing method and instrumental parameters (power and exposure time), this technique has the potential to quantify MWNTs in a variety of sample types (plants, earthworms, human blood, etc.). PMID:23298789

Li, Shibin; Irin, Fahmida; Atore, Francis O; Green, Micah J; Cañas-Carrell, Jaclyn E

2013-02-15

401

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

PubMed

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

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

2014-10-01

402

Emission of Methane by Eudrilus eugeniae and Other Earthworms from Brazil  

PubMed Central

Earthworms emit denitrification-derived nitrous oxide and fermentation-derived molecular hydrogen. The present study demonstrated that the earthworm Eudrilus eugeniae, obtained in Brazil, emitted methane. Other worms displayed a lesser or no capacity to emit methane. Gene and transcript analyses of mcrA (encoding the alpha subunit of methyl-CoM reductase) in gut contents of E. eugeniae suggested that Methanosarcinaceae, Methanobacteriaceae, and Methanomicrobiaceae might be associated with this emission. PMID:22344639

Depkat-Jakob, Peter S.; Hunger, Sindy; Schulz, Kristin; Brown, George G.; Tsai, Siu M.

2012-01-01

403

Emission of nitrous oxide from hydrocarbon contaminated soil amended with waste water sludge and earthworms  

Microsoft Academic Search

Soils in Mexico are often contaminated with hydrocarbons and addition of waste water sludge and earthworms accelerates their removal. However, little is known how contamination and subsequent bioremediation affects emissions of N2O and CO2. A laboratory study was done to investigate the effect of waste water sludge and the earthworm Eisenia fetida on emission of N2O and CO2 in a

Silvia M. Contreras-Ramos; Dioselina Álvarez-Bernal; Joaquín A. Montes-Molina; Oswald Van Cleemput; Luc Dendooven

2009-01-01

404

Earthworms, as ecosystem engineers, influence multiple aspects of a salamander’s ecology  

Microsoft Academic Search

Ecosystem engineers create habitat that can be used by other species in multiple ways, such as refuges from predators, places\\u000a to breed, or areas with increased prey resources. I conducted a series of enclosure experiments to: (1) determine if salamanders\\u000a use earthworm burrows, and (2) examine the potential influence of earthworm burrow use and indirect effects on salamander\\u000a intra- and

Tami S. Ransom

2011-01-01

405

Earthworm populations as affected by crop practices on clay loam soil in a Mediterranean climate  

Microsoft Academic Search

Earthworms influence soil fertility, and their population is known to be influenced by fertilization. The objective of this study is to characterize the abundance of earthworms under three different kinds of rotation-crops (Rotation: cereals–legumes for green manure-cotton), three tillage systems (Conventional Tillage CT, Minimum Tillage MT, & No-Tillage NT) and fertilization (NP: inorganic and FYM: farmyard manure-organic). Significantly higher populations

D. Bilalis; N. Sidiras; E. Vavoulidou; A. Konstantas

2009-01-01

406

Axial and radial pressure exerted by earthworms of different ecological groups  

Microsoft Academic Search

The aim of this study was to measure the pressures exerted by earthworms during burrowing. For this purpose we developed\\u000a two methods with which to quantify the axial and radial pressure. The data were recorded with an electronic balance that was\\u000a connected to a PC. Artificial earthworm burrows were used to standardize the measurements. Plexiglas tubes with diameters\\u000a ranging from

M. Keudel; S. Schrader

1999-01-01

407

Organochlorine pesticide residues in woodcock, soils and earthworms in Louisiana, 1965  

USGS Publications Warehouse

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.

McLane, M.A.R.; Stickel, L.F.; Newsom, J.D.

1971-01-01

408

Earthworms and the dissipation and distribution of atrazine in the soil profile  

Microsoft Academic Search

The influence of earthworms (Lumbricus terrestris L.) on the persistence and transport of 14C-labelled atrazine [2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine] in soil was studied in laboratory incubations using flask microcosms and packed columns. In soil microcosm incubations (12 or 30°C), [U-ring-14C]atrazine was dissipated and mineralized more rapidly in soil that had been conditioned (preincubated) with earthworms (e.g. soil containing worm castings) than in soil

A. Farenhorst; E. Topp; B. T. Bowman; A. D. Tomlin

2000-01-01

409

Earthworm additions increased short-term nitrogen availability and leaching in two grain-crop agroecosystems  

Microsoft Academic Search

Earthworms were added to enclosures in two agroecosystems to determine their influence on soil nitrogen availability and microbial activity, and to quantify their effect on the leaching of water and nitrogen through the surface soil. The two agroecosystems were a corn-soybean rotation with chisel-plow-disk tillage following corn (CS), and a corn-soybean-wheat-vetch rotation with ridge-tillage (CSW). In both agroecosystems, earthworm additions

Scott Subler; Christina M. Baranski; Clive A. Edwards

1997-01-01

410

Efficacy of methods for manipulating earthworm populations in large-scale field experiments in agroecosystems  

Microsoft Academic Search

We established a long-term field experiment in 1991 to investigate the influence of earthworms on C and N cycling processes in agroecosystems. In a replicated field experiment we decreased earthworm populations using electroshocking, increased them by adding field-collected worms or left them unmanipulated. Population manipulations and sampling were done twice per year in 20 m2 field enclosures that were made

P. J. Bohlen; R. W. Parmelee; J. M. Blair; C. A. Edwards; B. R. Stinner

1995-01-01

411

Quantification of nitrogen excretion rates for three lumbricid earthworms using 15 N  

Microsoft Academic Search

Nitrogen excretion rates of 15N-labeled earthworms and contributions of 15N excretion products to organic (dissolved organic N) and inorganic (NH4-N, NO3-N) soil N pools were determined at 10??°C and 18??°C under laboratory conditions. Juvenile and adult Lumbricus terrestris L., pre-clitellate and adult Aporrectodea tuberculata (Eisen), and adult Lumbricus rubellus (Hoffmeister) were labeled with 15N by providing earthworms with 15N-labeled organic

J. K. Whalen; R. W. Parmelee; S. Subler

2000-01-01

412

Earthworm and soil moisture effects on the productivity and structure of grassland communities  

Microsoft Academic Search

The objectives of this study were (1) to evaluate the eÄect of earthworm activity on aboveground plant biomass production of native calcareous grassland communities in NW-Switzerland and (2) to determine which plant functional types (graminoids, non-legume forbs and legumes) are most responsive as indicators of potential eÄects on plant community structure. Earthworm activity was manipulated in the field by creating

J. G. Zaller; J. A. Arnone

1999-01-01

413

Influence of earthworm activity on aggregate-associated carbon and nitrogen dynamics differs with agroecosystem management  

Microsoft Academic Search

Earthworms are known to be important regulators of soil structure and soil organic matter (SOM) dynamics, however, quantifying their influence on carbon (C) and nitrogen (N) stabilization in agroecosystems remains a pertinent task. We manipulated population densities of the earthworm Aporrectodea rosea in three maize-tomato cropping systems [conventional (i.e., mineral fertilizer), organic (i.e., composted manure and legume cover crop), and

Steven J. Fonte; Angela Y. Y. Kong; Chris van Kessel; Paul F. Hendrix; Johan Six

2007-01-01

414

Subcellular compartmentalization of lead in the earthworm, Eisenia fetida: Relationship to survival and reproduction  

Microsoft Academic Search

Metals are detoxified and sequestered into subcellular compartments when accumulated by earthworms. Differential centrifugation was used to quantify subcellular Pb in three separate studies to measure 14-day acute toxicity (lethality), 28\\/56-day reproductive effects, and 90-day bioaccumulation in spiked-soil exposed earthworms, Eisenia fetida. Observed toxicity and total body Pb was consistent with published work of others. Pb showed concentration-dependent toxicity relationships

Robert P. Jones; Anthony J. Bednar; Laura S. Inouye

2009-01-01

415

Toxicity of chromium(III) and chromium(VI) to the earthworm Eisenia fetida  

Microsoft Academic Search

The effects of Cr(III) and Cr(VI) on the survival, behavior, and morphology of the earthworm, Eisenia fetida, in water at pH 6, 7, and 8 and their toxicity in 10 different soils and an organic substrate have been assessed. A decrease in the pH of water resulted in increased toxicity of Cr to the earthworm. In water, both Cr species

S. Sivakumar; C. V. Subbhuraam

2005-01-01

416

Comparative efficacy of three epigeic earthworms under different deciduous forest litters decomposition  

Microsoft Academic Search

An experiment was conducted during 1998–1999, in a deciduous forest located in the semi-arid tropics of central India, to evaluate the suitability of different forest litters as food material for the tropical epigeic earthworms i.e. Eisenia fetida (Savigny), Perionyx excavatus (Perrier) and Dicogaster bolaui (michaelsen). The aim was to examine the influence of these earthworms on the decomposition processes of

M. C Manna; S Jha; P. K Ghosh; C. L Acharya

2003-01-01

417

Assessing the Role of Earthworms in Biocontrol of Soil-Borne Plant Fungal Diseases  

Microsoft Academic Search

\\u000a Earthworms are integral part of belowground communities, which are actively involved in redesigning the structure of the soil\\u000a environment. In recent decades, several researches have shown the potential of application of vermicompost in controlling\\u000a soil-borne plant fungal diseases. However, complexity of earthworm interactions with various abiotic and biotic components\\u000a of the soil has posed a real challenge before the scientists

Mukesh K. Meghvansi; Lokendra Singh; Ravi B. Srivastava; Ajit Varma

418

DNA damage and effects on antioxidative enzymes in earthworm ( Eisenia foetida) induced by atrazine  

Microsoft Academic Search

To evaluate atrazine (2-chloro-4-ethylamino-6-isopropylamino-1, 3, 5-triazine) ecotoxicology in soil, the effect of atrazine on the activity of antioxidative enzymes (superoxide dismutase, SOD; catalase, CAT; and guaiacol peroxidase, POD) and DNA damage induced by atrazine were investigated in earthworms. Atrazine was added to artificial soil at rates of 0, 2.5, 5 and 10mg per kg of soil. Earthworm tissues exposed to

Y. Song; L. S. Zhu; J. Wang; J. H. Wang; W. Liu; H. Xie

2009-01-01

419

Testing Honey Bees' Avoidance of Predators  

ERIC Educational Resources Information Center

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)…

Robinson, Jesse Wade; Nieh, James C.; Goodale, Eben

2012-01-01

420

Harm Avoidance and Risk of Alzheimer's Disease  

PubMed Central

Objective To test the hypothesis that harm avoidance, a trait associated with behavioral inhibition, is associated with risk of developing Alzheimer’s disease. Methods A total of 791 adults aged 55 years and older without dementia completed a standard self report measure of harm avoidance. They then underwent annual evaluations that included detailed cognitive testing and clinical classification of mild cognitive impairment, dementia and Alzheimer’s disease. In a uniform neuropathologic examination of those who died, counts of neuritic plaques diffuse plaques, and neurofibrillary tangles were standardized and combined to yield a pathologic measure of disease. The relation of harm avoidance to incidence of Alzheimer’s disease and related outcomes was estimated in analyses adjusted for age, sex, and education. Results During a mean of 3.5 years of annual observation, 98 people (12.4%) developed incident Alzheimer’s disease. High level of harm avoidance (90th percentile) was associated with a more than twofold increase in risk of Alzheimer’s disease compared to a low score (10th percentile). Higher harm avoidance was also associated with increased incidence of mild cognitive impairment and more rapid decline in episodic memory, working memory, and perceptual speed (but not semantic memory or visuospatial ability). In 116 participants who died and underwent brain autopsy, harm avoidance was not related to a composite measure of plaques and tangles. Conclusion High level of the harm avoidance trait, indicating a tendency toward behavioral inhibition, is related to risk of developing Alzheimer’s disease and its precursor, mild cognitive impairment. PMID:21949425

Wilson, Robert S.; Boyle, Patricia A.; Buchman, Aron S.; Yu, Lei; Arnold, Steven E.; Bennett, David A.

2011-01-01

421

Lethal critical body residues as measures of Cd, Pb, and Zn bioavailability and toxicity in the earthworm Eisenia fetida  

Microsoft Academic Search

Background  Earthworm heavy metal concentrations (critical body residues, CBRs) may be the most relevant measures of heavy metal bioavailability\\u000a in soils and may be linkable to toxic effects in order to better assess soil ecotoxicity. However, as earthworms possess physiological\\u000a mechanisms to secrete and\\/or sequester absorbed metals as toxicologically inactive forms, total earthworm metal concentrations\\u000a may not relate well with toxicity.

Jason M. Conder; Roman P. Lanno

2003-01-01

422

Lethal critical body residues as measures of Cd, Pb, and Zn bioavailability and toxicity in the earthworm Eisenia fetida  

Microsoft Academic Search

Background. Earthworm heavy metal concentrations (critical body residues, CBRs) may be the most relevant measures of heavy\\u000a metal bioavailability in soils and may be linkable to toxic effects in order to better assess soil ecotoxicity. However, as\\u000a earthworms possess physiological mechanisms to secrete and\\/or sequester absorbed metals as toxicologically inactive forms,\\u000a total earthworm metal concentrations may not relate well with

Jason M. Conder; Roman P. Lanno

2003-01-01

423

Toxicological effects of TiO 2 and ZnO nanoparticles in soil on earthworm Eisenia fetida  

Microsoft Academic Search

Nanoparticles (NPs) of TiO2 and ZnO are receiving increasing attention due to their widespread applications. To evaluate their toxicities to the earthworm Eisenia fetida (Savigny, 1826) in soil, artificial soil systems containing distilled water, 0.1, 0.5, 1.0 or 5.0gkg?1 of NPs were prepared and earthworms were exposed for 7 days. Contents of Zn and Ti in earthworm, activities of antioxidant

C. W. Hu; M. Li; Y. B. Cui; D. S. Li; J. Chen; L. Y. Yang

2010-01-01

424

Spring dynamics of soil carbon, nitrogen, and microbial activity in earthworm middens in a no-till cornfield  

Microsoft Academic Search

Earthworm activity may be an important cause of spatial and temporal heterogeneity of soil properties in agroecosystems.\\u000a Structures known as “earthworm middens,” formed at the soil surface by the feeding and casting activities of some earthworms,\\u000a may contribute significantly to this heterogeneity. We compared the temporal dynamics of carbon (C), nitrogen (N), and microbial\\u000a acitivity in Lumbricus terrestris middens and

S. Subler; A. S. Kirsch

1998-01-01

425

Influence of earthworm activity on microbial communities related with the degradation of persistent pollutants.  

PubMed

Earthworms may promote the biodegradation of polycyclic aromatic hydrocarbons (PAHs) in soil, but the mechanism through which they exert such influence is still unknown. To determine if the stimulation of PAH degradation by earthworms is related to changes in microbial communities, a microcosm experiment was conducted consisting of columns with natural uncontaminated soil covered with PAH-contaminated dredge sediment. Columns without and with low and high Eisenia andrei densities were prepared. Organic matter and PAH content, microbial biomass, and dehydrogenase activity (DHA) were measured in soil and sediment over time. Biolog Ecoplate™ and polymerase chain reaction using denaturing gradient gel electrophoresis were used to evaluate changes in metabolic and structural diversity of the microbial community, respectively. Earthworm activity promoted PAH degradation in soil, which was significant for biphenyl, benzo[a]pyrene, and benzo[e]pyrene. Microbial biomass and DHA activity generally did not change over the experiment. Earthworm activity did change microbial community structure, but this did not affect its functioning in terms of carbon substrate consumption. Results suggest no relationship between changes in the microbial community by earthworm activity and increased PAH disappearance. The role of shifts in soil microbial community structure induced by earthworms in PAH removal needs further investigation. PMID:22213518

Natal-da-Luz, Tiago; Lee, Iwa; Verweij, Rudo A; Morais, Paula V; Van Velzen, Martin J M; Sousa, José Paulo; Van Gestel, Cornelis A M

2012-04-01

426

Persistence in earthworms and potential hazards to birds of soil applied DDT, dieldrin, and heptachlor  

USGS Publications Warehouse

(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.

Beyer, W.N.; Gish, C.D.

1980-01-01

427

New methodology for determining chronic effects on the earthworm, Eisenia foetida  

SciTech Connect

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.

Garvey, N.A. [Springborn Labs., Inc., Wareham, MA (United States)

1994-12-31

428

Influence of soil properties on molybdenum uptake and elimination kinetics in the earthworm Eisenia andrei.  

PubMed

This study aimed at determining the uptake and elimination kinetics of molybdenum in the earthworm Eisenia andrei, and the influence of soil properties on molybdenum bioaccumulation. Three natural and four artificial soils were spiked at concentrations of 10 and 100 microg Mo g(-1) dry soil. Earthworms were exposed individually to spiked soils and sampled at different time intervals for 21 d. Remaining earthworms were transferred to non-spiked soil to determine elimination, also for 21 d. Uptake and elimination rate constants and bioaccumulation factors (BAFs) were calculated using a one-compartment model, and related to total, water and CaCl2 extractable molybdenum concentrations in soil. Molybdenum was rapidly accumulated by the earthworms with uptake rate constants between 0.05 and 1.70 g dry soil g(-1) dry earthworm d(-1), and equilibrium generally was reached within 10 d. Molybdenum was not strongly bioaccumulated (BAFearthworms was mainly affected by soil pH and organic carbon content. PMID:20674662

Díez-Ortiz, Maria; Giska, Iwona; Groot, Maartje; Borgman, Eef M; Van Gestel, Cornelis A M

2010-08-01

429

Earthworms Dilong: Ancient, Inexpensive, Noncontroversial Models May Help Clarify Approaches to Integrated Medicine Emphasizing Neuroimmune Systems  

PubMed Central

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

Cooper, Edwin L.; Balamurugan, Mariappan; Huang, Chih-Yang; Tsao, Clara R.; Heredia, Jesus; Tommaseo-Ponzetta, Mila; Paoletti, Maurizio G.

2012-01-01

430

Enantioselective toxicity, bioaccumulation and degradation of the chiral insecticide fipronil in earthworms (Eisenia feotida).  

PubMed

The enantioselective acute toxicity to earthworms of racemic fipronil and its individual enantiomers was studied. R-(-)-fipronil was approximately 1.5 times more toxic than the racemate and approximately 2 times more toxic than S-(+)-fipronil after 72 and 96 h of exposure, respectively. Assays of fipronil enantiomer bioaccumulation and degradation in earthworms were conducted. The bio-concentration factors (BCFs) were slightly different between the two enantiomers. The enantiomeric fraction (EF) values in earthworms in the bioaccumulation period were approximately 0.5, which indicated there was no enantioselective bioaccumulation. In contrast, the degradation of fipronil in earthworms was enantioselective: the t1/2 values for R- and S-fipronil were 3.3 and 2.5 days, respectively, in natural soil, and 2.1 and 1.4 days, respectively, in artificial soil. The results of soil analyses showed that the degradation of fipronil was not enantioselective, which suggested that the enantioselectivity of fipronil in earthworms results from the organism's metabolism. The study also demonstrated that the presence of earthworms could accelerate the degradation of fipronil in soil. PMID:24742550

Qu, Han; Wang, Peng; Ma, Rui-xue; Qiu, Xing-xu; Xu, Peng; Zhou, Zhi-qiang; Liu, Dong-hui

2014-07-01

431

The “deduction” approach: A non-invasive method for estimating secondary production of earthworm communities  

NASA Astrophysics Data System (ADS)

Secondary production is an important parameter for the study of population dynamics and energy flow through animal communities. Secondary production of earthworm communities has been determined with the size-frequency and instantaneous growth rate methods, whereby earthworm populations are repeatedly sampled at regular intervals and the change in biomass of cohorts or individuals between sampling dates is determined. The major disadvantage of repeated sampling is that it disturbs the soil and permanently removes earthworms from the study area. The " deduction" approach is a theoretical model that partitions individuals into defined pools and makes assumptions about the growth, recruitment and mortality of each pool. In 2004 and 2005, earthworms were added to undisturbed field enclosures and the " deduction" approach was used to estimate secondary production of the indigenous and added earthworm populations during the crop growing period (17-18 weeks) in each year. Secondary production estimates made by the " deduction" approach were similar to estimates from direct earthworm sampling in temperate agroecosystems. The "deduction" approach is an indirect method that estimates population dynamics and secondary production, and is appropriate for manipulation experiments where removal of organisms and physical disturbance of the habitat by repeated sampling could bias results.

Eriksen-Hamel, Nikita S.; Whalen, Joann K.

2009-05-01

432

Self-Assemblage and Quorum in the Earthworm Eisenia fetida (Oligochaete, Lumbricidae)  

PubMed Central

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

Zirbes, Lara; Brostaux, Yves; Mescher, Mark; Jason, Maxime; Haubruge, Eric; Deneubourg, Jean-Louis

2012-01-01

433

The influence of earthworms on nutrient dynamics during the process of vermicomposting.  

PubMed

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

Domínguez, Jorge; Gómez-Brandón, María

2013-08-01

434

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

PubMed

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

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

2014-07-01

435

Further records of non-cryptic New Zealand earthworms  

PubMed Central

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

Blakemore, Robert

2011-01-01

436

Avoidance learning in phenylketonuric monkeys  

Microsoft Academic Search

Compared 16 rhesus monkeys fed damagingly high levels of phenylalanine when young (phenylketonuric monkeys-PKUs) with 16 controls on shuttle-box shock avoidance. Results demonstrate that punishing intertrial crosses (ITCs) early in acquisition produced in PKUs subsequent deterioration in avoiding the shock both of the CS and of the ITC. CS errors tended to follow other errors, suggesting increased emotionality in the

Arnold S. Chamove; Harry F. Harlow

1973-01-01

437

A new method to measure allyl isothiocyanate (AITC) concentrations in mustard -1 Comparison of AITC and commercial mustard solutions as earthworm extractants2  

E-print Network

;3 Abstract31 Earthworms are target organisms both for scientists studying the biological component32 of soils of AITC and commercial mustard solutions as earthworm extractants2 3 C. Pelosia, *, F. Chironb , F. Dubsc mustard solutions had the same earthworm extracting efficiency30 hal-00981416,version1-23Apr2014 #12

438

Influence of exotic earthworm invasion on soil organic matter, microbial biomass and denitrification potential in forest soils of the northeastern United States  

Microsoft Academic Search

Formerly glaciated regions of the northeastern United States have few native earthworm species and the region is dominated by exotic earthworms from Europe and Asia. Earthworms of the Asian Megascolecid genus Amynthas, common in many forests of the southeastern US, are invading new habitats in north of their reported range in the northeastern US. At the Cary Arboretum in Millbrook,

Amy E Burtelow; Patrick J Bohlen; Peter M Groffman

1998-01-01

439

Earthworms as bioindicator of metals (Zn, Fe, Mn, Cu, Pb and Cd) in soils: Is metal bioaccumulation affected by their ecological category?  

Microsoft Academic Search

The importance of earthworms in metal pollution monitoring is widely recognized in terrestrial ecosystems. Metal bioaccumulation by soil-dwelling earthworms can be used as an ecological indicator of metal availability in soils. In this study, we quantify the level of DTPA extractable metals in casts and tissues of earthworms (endogeic: Metaphire posthuma (Vaillant) and anecic: Lampito mauritii Kinberg) and ingesting soils,

Surindra Suthar; Sushma Singh; Sachin Dhawan

2008-01-01

440

Collison avoidance for automated inspection  

NASA Astrophysics Data System (ADS)

In certain automated inspection systems, computer controlled sensors are required to move arbitrarily close to the objects under inspection, whose geometries and positions may be unknown. There exists a potential for collisions which can cause damage to the sensor and the objects. A method based upon two representations is presented which ensures collision-free motions of the sensor and positioning apparatus. The sensed environment is modelled as a discrete volumetric grid called a voxel map, which is incrementally maintained as range data is acquired. The sensor and all moving attachments are modelled as sets of spheres. The method provides a conservative underestimate of the minimum distance between the surfaces of the sensor system and all workspace obstacles within a known error bound. The conditions are derived for which a continuous collision-free trajectory exists between two configurations. These are two operational modes where collision avoidance is useful. In direct teleoperation mode, the operator has joystick control over the position of the sensor, and potential collisions are detected and averted in real-time. In autonomous mode, the sensor path is planned automatically, and collision-free motions are generated by invoking the collision detection method within an enumerative search routine. The method has been implemented and tested using a scanning laser range camera as the sensor and a Puma 560 manipulator as the positioning apparatus.

Greenspan, Michael

1997-01-01

441

Interactions of an introduced shrub and introduced earthworms in an Illinois urban woodland: Impact on leaf litter decomposition  

Microsoft Academic Search

Summary This study examined an 'invasional meltdown', where the invasion of a Midwestern woodland by an exotic shrub (Rhamnus cathartica L.P. Mill) and the invasion by Eurasian earthworms facilitated one another. Using a litterbag approach, we examined mass loss of four substrates (R. cathartica, Acer saccharum, Quercus rubra, and Quercus alba) along a gradient of Eurasian earthworm density and biomass

Liam Heneghan; James Steffen; Kristen Fagen

2007-01-01

442

Earthworms increase the ratio of bacteria to fungi in northern hardwood forest soils, primarily by eliminating the organic horizon  

Microsoft Academic Search

The exotic earthworm invasion in hardwood forests of the northern United States is associated with many ecosystem-level changes. However, less is known about the effects of the invasion on the composition of the soil microbial community through which ecosystem-level changes are mediated. Further, earthworm effects on soil microbial community composition have not been well studied in the field. To evaluate

Mark A. Dempsey; Melany C. Fisk; Timothy J. Fahey

2011-01-01

443

Allometric estimation of earthworm ash-free dry mass from diameters and lengths of select megascolecid and lumbricid species  

E-print Network

Allometric estimation of earthworm ash-free dry mass from diameters and lengths of select University, Department of Biological Sciences, 374 Dodge Hall of Engineering, Rochester, MI 48071, USA b-free dry mass allometric equations for seven earthworm species from the families Megascolecidae

Tiegs, Scott

444

Earthworm response to 10 weeks of incubation in a pot with acid mine spoil, sewage sludge, and lime  

Microsoft Academic Search

Applications of sewage sludge and lime have been used to restore some of the nearly 1.0 million ha of unreclaimed acid mine spoils in the United States. Earthworms might also aid in the reconstruction of mine spoils, but the earthworm response to mine spoils and sludge has not been widely studied. The objective of the present study was to examine

E. Pallant; L. M. Hilster

1996-01-01

445

Effects of seasonal and diurnal temperature fluctuations on population dynamics of two epigeic earthworm species in forest soil  

Microsoft Academic Search

Temperature fluctuations are a fundamental entity of the soil environment in the temperate zone and show fast (diurnal) and slow (seasonal) dynamics. However, responses of soil ecosystem engineers, such as earthworms, to annual temperature dynamics are virtually unknown. We studied growth, mortality and cocoon production of epigeic earthworm species (Lumbricus rubellus and Dendrobaena octaedra) exposed to temperature fluctuations in root-free

Alexei V. Uvarov; Alexei V. Tiunov; Stefan Scheu

2011-01-01

446

Earthworm activity affecting organic matter, aggregation and microbial activity in soils restored after opencast mining for coal  

Microsoft Academic Search

Earthworms were introduced into physically degraded soils restored after opencast coal mining. Their effects on soil organic matter and associated soil aggregation were then measured after a period of 9 yr. Earthworm inputs increased stable aggregation and resulted in a higher proportion of the soil organic matter as carbohydrates. Although the total amount of organic matter in the top 15

J. Scullion; A. Malik

2000-01-01

447

Oral sealing using glue: a new method to distinguish between intestinal and dermal uptake of metals in earthworms  

Microsoft Academic Search

Earthworms may take up chemicals from soil and pore water, both through their skin (dermal) and by ingestion (oral). It remains unclear, however, what the relative importance of these pathways is. To assess bioavailability of pollutants in soil to earthworms, it is necessary that the contribution of each pathway is known. Lumbricus rubellus were sealed by means of medical histoacryl

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

2003-01-01

448

Assessment of earthworm burrowing efficiency in compacted soil with a combination of morphological and soil physical measurements  

Microsoft Academic Search

Column experiments were carried out to quantify the effect of earthworms on compacted soil. The earthworms (Lumbricus terrestris) were able to burrow into soil which was artificially compacted to a pore volume as low as 40%; they may also penetrate an artificial “plough pan” deep in the soil. The effect of the burrowing activity of Lumbricus terrestris was quantified by

M. Joschko; H. Diestel; O. Larink

1989-01-01

449

The influence of earthworms (Lumbricidae) on the nitrogen dynamics in the soil litter system of a deciduous forest  

Microsoft Academic Search

The influence of earthworms (Aporrectodea caliginosa (Savigny) and Lumbricus castaneus (Savigny)) on the rate of nitrogen net mineralization of the soil was studied in the laboratory and in the field. The additional mineralization of nitrogen cause by the burrowing activity of the substrat feeding earthworm A. caliginosa (NL)was directly correlated to the biomass of the lumbricids independently of their number.

S. Scheu

1987-01-01

450

An overview of some tillage impacts on earthworm population abundance and diversity — implications for functioning in soils  

Microsoft Academic Search

Conflicting reports in the literature on the effects of tillage on earthworms are reviewed in the light of their roles in agro-ecosystem functioning. Tillage can change the abundance (by 2–9 times) as well as the composition (diversity) of earthworm populations. The actual impact is dependent on soil factors, climatic conditions and the tillage operations but hitherto this information was seldom

K. Y Chan

2001-01-01

451

Use of an earthworm lysosomal biomarker for the ecological assessment of pollution from an industrial plastics fire  

Microsoft Academic Search

A low-cost field technique employing retention of the dye neutral-red by lysosomes in coelomocyte cells taken from earthworms (Lumbricus castaneus), was used as a means of assessing the ecological effects (if any) of an industrial accident. Earthworms and soil samples were collected at the site of a large industrial plastics fire in Thetford, UK along a 200 m transect leading

Claus Svendsen; Andrew A. Meharg; Paul Freestone

1996-01-01

452

Acceleration of cellulose and organic matter decomposition as a result of earthworms effect on soil microbial community  

Microsoft Academic Search

The biotic activity of earthworms alters soil carbon turnover 1) indirectly by the disturbance of soil structure which increases the availability of organic matter; or 2) directly changing the structure of soil microbial community which is mainly in the dormant state in undisturbed soil. The activation of soil microorganisms by earthworms can strongly change the turnover of native soil organic

Evgenia Blagodatskaya; Nikita Khomyakov; Sergey Blagodatsky; Olga Myachina; Boris Byzov; Yakov Kuzyakov

2010-01-01

453

Earthworms strongly modify microbial biomass and activity triggering enzymatic activities during vermicomposting independently of the application rates of pig slurry  

Microsoft Academic Search

We studied the relationships between earthworm activity, microbial biomass and the activation and dynamics of several enzyme activities. We carried out an experiment in which low and high rates (1.5 and 3 kg respectively) of pig slurry were applied to small scale reactors with and without earthworms. We found that extracellular enzyme activity increased with rate of pig slurry. In both

Manuel Aira; Fernando Monroy; Jorge Domínguez

2007-01-01

454

Assessment of anecic behavior in selected earthworm species: Effects on wheat seed burial, seedling establishment, wheat growth and litter incorporation  

Microsoft Academic Search

Anecic earthworm species function as ecosystem engineers by structuring the soil environment, incorporating large amounts of litter and seeds into soil and, thereby influence the composition of plant communities. The aim of the present greenhouse experiment was to investigate the effects of three apparently anecic earthworm species on wheat seed burial, seedling establishment, wheat growth and litter incorporation. The three

Nico Eisenhauer; Sven Marhan; Stefan Scheu

2008-01-01