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Sample records for earthworms survive freezing

  1. Small Dendrobaena earthworms survive freezing better than large worms

    DEFF Research Database (Denmark)

    Holmstrup, Martin; Overgaard, Johannes; Bayley, Mark

    2007-01-01

    Dendrobaena octaedra is a freeze tolerant earthworm widely distributed in boreal regions. Specimens collected in Sweden were cold acclimated and then frozen at -7 degrees C to examine the influence of body mass on survival of freezing. Results showed that survival was negatively correlated to body mass. Glycogen content of the worms was variable and seemed to decrease with increasing body mass consistent with the hypothesis that freeze survival is dependent on the ability to rapidly break down g...

  2. Small Dendrobaena earthworms survive freezing better than large worms

    DEFF Research Database (Denmark)

    Holmstrup, Martin; Overgaard, Johannes

    2007-01-01

    Dendrobaena octaedra is a freeze tolerant earthworm widely distributed in boreal regions. Specimens collected in Sweden were cold acclimated and then frozen at -7 degrees C to examine the influence of body mass on survival of freezing. Results showed that survival was negatively correlated to body mass. Glycogen content of the worms was variable and seemed to decrease with increasing body mass consistent with the hypothesis that freeze survival is dependent on the ability to rapidly break down glycogen and accumulate high concentrations of glucose. The results suggest that large worms (subadults and adults) invest energy in production of cocoons at the expense of glycogen storage for cryoprotectant production, whereas juvenile worms increase their survival chances by investing energy in glycogen storage at the expense of growth as a preparation for winter.

  3. Dual roles of glucose in the freeze-tolerant earthworm Dendrobaena octaedra: cryoprotection and fuel for metabolism

    DEFF Research Database (Denmark)

    Calderon, Sofia; Holmstrup, Martin; Westh, Peter; Overgaard, Johannes

    2009-01-01

    Ectothermic animals inhabiting the subarctic and temperate regions have evolved strategies to deal with periods of continuous frost during winter. The earthworm Dendrobaena octaedra is freeze tolerant and accumulates large concentrations of glucose upon freezing. The present study investigates the roles of glucose accumulation for long-term freeze tolerance in worms kept frozen at -2 degrees C for 47 days. During this period, worms were sampled periodically for determination of survival and for ...

  4. Freezing of body fluids induces metallothionein gene expression in earthworms (Dendrobaena octaedra)

    DEFF Research Database (Denmark)

    Fisker, Karina Vincents; Holmstrup, Martin

    2016-01-01

    The molecular mechanisms activated by environmental contaminants and natural stressors such as freezing need to be investigated in order to better understand the mechanisms of interaction and potential effects that combined stressors may have on organisms. Using the freeze tolerant earthworm Dendrobaena octaedra as model species, we exposed worms to freezing and exposure to sublethal copper in a factorial design and investigated the transcription of candidate genes for metal and cold stress. We hypothesized that both freezing and copper would induce transcription of genes coding for heat shock proteins (hsp10 and hsp70), metallothioneins (mt1 and mt2) and glutathione-S-transferase (gst), and that the combined effects of these two stressors would be additive. The gene transcripts hsp10, hsp70 and gst were significantly upregulated by freezing, but only hsp10 was upregulated by copper. We found that copper at the time of sampling had no effect on transcription of two metallothionein genes whereas transcription was strongly upregulated by freezing. Moreover there was a significant interaction causing more than additive transcription rates of mt1 in the copper/freezing treatment suggesting that freeze-induced cellular dehydration increases the concentration of free copper ions in the cytosol. This metallothionein response to freezing is likely adaptive and possibly provides protection against freeze-induced elevated metal concentrations in the cytosol and excess ROS levels due to hypoxia during freezing.

  5. Hatchling turtles survive freezing during winter hibernation.

    OpenAIRE

    Storey, K. B.; J.M. Storey; Brooks, S P; Churchill, T A; Brooks, R. J.

    1988-01-01

    Hatchlings of the painted turtle (Chrysemys picta marginata) are unique as the only reptile and highest vertebrate life form known to tolerate the natural freezing of extracellular body fluids during winter hibernation. Turtles survived frequent exposures to temperatures as low as -6 degrees C to -8 degrees C in their shallow terrestrial nests over the 1987-1988 winter. Hatchlings collected in April 1988 had a mean supercooling point of -3.28 +/- 0.24 degrees C and survived 24 hr of freezing ...

  6. Dual roles of glucose in the freeze-tolerant earthworm Dendrobaena octaedra: cryoprotection and fuel for metabolism

    DEFF Research Database (Denmark)

    Calderon, Sofia; Holmstrup, Martin; Westh, Peter; Overgaard, Johannes

    2009-01-01

    Ectothermic animals inhabiting the subarctic and temperate regions have evolved strategies to deal with periods of continuous frost during winter. The earthworm Dendrobaena octaedra is freeze tolerant and accumulates large concentrations of glucose upon freezing. The present study investigates the...... roles of glucose accumulation for long-term freeze tolerance in worms kept frozen at -2 degrees C for 47 days. During this period, worms were sampled periodically for determination of survival and for measurements of glucose, glycogen, lactate, alanine and succinate. In addition we performed...... calorimetric measurements to assess metabolic rate of frozen and unfrozen worms. Long-term freezing was associated with a gradual depletion of glucose and worms that succumbed during this period were always characterised by low glucose and glycogen levels. The anaerobic waste products lactate and alanine...

  7. Survival of freeze-dried Lactobacillus plantarum and Lactobacillus

    OpenAIRE

    Carvalho, A. Sofia; Silva, Joana; Ho, Peter; Teixeira, Paula; Malcata, F. Xavier; Gibbs, Paul

    2002-01-01

    No significant differences were observed in the viability of Lactobacillus plantarum and Lactobacillus rhamnosus cells during freeze-drying in the presence or absence of inositol, sorbitol, fructose, trehalose, monosodium glutamate and propyl gallate. However, survival was higher during storage when drying took place in the presence of these compounds. Sorbitol produced more significant effects than the other compounds toward maintaining viability of freeze-dried L. plantarum and ...

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

    Science.gov (United States)

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

    2016-03-01

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

  9. Survival differences among freeze-dried genetically engineered and wild-type bacteria.

    OpenAIRE

    Israeli, E; Shaffer, B. T.; Hoyt, J A; Lighthart, B; Ganio, L M

    1993-01-01

    Because the death mechanisms of freeze-dried and air-dried bacteria are thought to be similar, freeze-drying was used to investigate the survival differences between potentially airborne genetically engineered microorganisms and their wild types. To this end, engineered strains of Escherichia coli and Pseudomonas syringae were freeze-dried and exposed to air, visible light, or both. The death rates of all engineered strains were significantly higher than those of their parental strains. Light...

  10. Antifreeze proteins enable plants to survive in freezing conditions

    Indian Academy of Sciences (India)

    Ravi Gupta; Renu Deswal

    2014-12-01

    Overwintering plants secrete antifreeze proteins (AFPs) to provide freezing tolerance. These proteins bind to and inhibit the growth of ice crystals that are formed in the apoplast during subzero temperatures. Antifreeze activity has been detected in more than 60 plants and AFPs have been purified from 15 of these, including gymnosperms, dicots and monocots. Biochemical characterization of plant antifreeze activity, as determined by the high ice recrystallization inhibition (IRI) activities and low thermal hysteresis (TH) of AFPs, showed that their main function is inhibition of ice crystal growth rather than the lowering of freezing temperatures. However, recent studies showed that antifreeze activity with higher TH also exists in plants. Calcium and hormones like ethylene and jasmonic acid have been shown to regulate plant antifreeze activity. Recent studies have shown that plant AFPs bind to both prism planes and basal planes of ice crystals by means of two flat ice binding sites. Plant AFPs have been postulated to evolve from the OsLRR-PSR gene nearly 36 million years ago. In this review, we present the current scenario of plant AFP research in order to understand the possible potential of plant AFPs in generation of freezing-tolerant crops.

  11. Freeze-drying of Lactobacillus coryniformis Si3--effects of sucrose concentration, cell density, and freezing rate on cell survival and thermophysical properties.

    Science.gov (United States)

    Schoug, Asa; Olsson, Johan; Carlfors, Johan; Schnrer, Johan; Hkansson, Sebastian

    2006-08-01

    Freeze-drying is commonly used to stabilize lactic acid bacteria. Many factors have been reported to influence freeze-drying survival, including bacterial species, cell density, lyoprotectant, freezing rate, and other process parameters. Lactobacillus coryniformis Si3 has broad antifungal activity and a potential use as a food and feed biopreservative. This strain is considered more stress sensitive, with a low freeze-drying survival, compared to other commercialized antifungal lactic acid bacterial strains. We used a response surface methodology to evaluate the effects of varying sucrose concentration, cell density and freezing rate on Lb. coryniformis Si3 freeze-drying survival. The water activity of the dry product, as well as selected thermophysical properties of importance for freeze-drying; degree of water crystallization and the glass transition temperature of the maximally freeze concentrated amorphous phase (Tg') were determined. The survival of Lb. coryniformis Si3 varied from less than 6% to over 70% between the different conditions. All the factors studied influenced freeze-drying survival and the most important factor for survival is the freezing rate, with an optimum at 2.8 degrees C/min. We found a co-dependency between freezing rate and formulation ingredients, indicating a complex system and the need to use statistical tools to detect important interactions. The degree of water crystallization decreased and the final water activity increased as a function of sucrose concentration. The degree of water crystallization and Tg' was not affected by the addition of 10(8)-10(10) CFU/ml. At 10(11) CFU/ml, these thermophysical values decreased possibly due to increased amounts of cell-associated unfrozen water. PMID:16756971

  12. Effects of petroleum and metal contaminated soil on plants and earthworms: Survival and bioaccumulation

    International Nuclear Information System (INIS)

    Earthworms, Eisenia foetida, and bermudagrass, Cynodon dactylon, were used in the laboratory to test the toxicity of contaminated sediment taken from a small fresh water lake in North Carolina. This work was part of an investigation to determine the potential effects of upland disposal of this sediment. The contaminated sediment contained As, Cr, Cu, Pb, Hg, Ni, Zn and petroleum hydrocarbons at concentrations much greater than nearby soils. Test cylinders were planted with bermudagrass; earthworms were added 30 days later. Both species were harvested at 60 days, weighed and submitted for chemical analyses. Cynodon was affected by the contaminated sediment but grew well in the mixtures of sediment and upland soil. Similar results were obtained with the Eisenia. These species did not accumulate hydrocarbons from the sediment with the possible exception of pyrene. The metals Cd, Pb, and Zn were elevated in plants exposed to the contaminated sediment. Earthworms exposed to this sediment accumulated Pb to concentrations greater than animals exposed to the manure control. This work demonstrated that a contaminated freshwater sediment was not toxic to plants or earthworms and that most petroleum hydrocarbons were not accumulated. The only metal that may be of some concern was Pb

  13. The Effects of Acid Substances under The Freezing Process on The Survival of Plant Cells

    Science.gov (United States)

    Inada, Hidetoshi; Fujikawa, Seizo; Arakawa, Keita

    The objective of this study was to clarify the mechanism of injury caused by acid snow stress in wintering plants. In this study, influence of simulated acid snow stress on leaf tissues of wintering plant was conveniently estimated by extracellular freezing tests under acid conditions in vitro. The survival rates of leaf tissues after freeze-thawing with 0.3 ml of sulfuric acid solution of pH 2.0 were significantly decreased, compared with the survival rates under acid condition of pH 3.0 or pure water. In this study, the initial volume of sulfuric acid solutions was the same in the treatments. Therefore, it is thought that the more acidic the initial pH of sulfuric acid solution becomes, the greater the volume of residual unfrozen solution with concentrated sulfuric acid in the extracellular part at a subzero temperature would be, consequently, the survival rate of leaf tissues were decreased. When leaf tissues were freeze-thawed with a large volume of sulfuric acid solution of pH 3.0, the survival rate of leaf tissues was comparable to the survival rate using pH 2.0. These results suggest that an increase in the volume of acid meltwater derived from snow cover will enhance the damage to wintering plants even the mild acidity of the acid snow.

  14. Survival and Growth of Epidemically Successful and Nonsuccessful Salmonella enterica Clones after Freezing and Dehydration.

    DEFF Research Database (Denmark)

    Mller, Karoline; Aabo, Sren

    2012-01-01

    The spread of epidemically successful nontyphoidal Salmonella clones has been suggested as the most important cause of salmonellosis in industrialized countries. Factors leading to the emergence of success clones are largely unknown, but their ability to survive and grow after physical stress may contribute. During epidemiological studies, a mathematical model was developed that allowed estimation of a factor (q) accounting for the relative ability of Salmonella serovars with different antimicrobial resistances to survive in the food chain and cause human disease. Based on this q-factor, 26 Salmonella isolates were characterized as successful or nonsuccessful. We studied the survival and growth of stationary- and exponential-phase cells of these isolates after freezing for up to 336 days in minced meat. We also investigated survival and growth after dehydration at 10C and 82% relative humidity (RH) and 25C and 49% RH for 112 days. Stationary-phase cells were reduced by less than 1 log unit during 1 year of freezing, and growth was initiated with an average lag phase of 1.7 h. Survival was lower in exponentialphase cells, but lag phases tended to be shorter. High humidity and low temperature were less harmful to Salmonella than were low humidity and high temperature. Tolerance to adverse conditions was highest for Salmonella Infantis and one Salmonella Typhimurium U292 isolate and lowest for Salmonella Derby and one Salmonella Typhimurium DT170 isolate. Dehydration, in contrast to freezing, was differently tolerated by the Salmonella strains in this study, but tolerance to freezing and dehydration does not appear to contribute to the emergence of successful Salmonella clones.

  15. Survival after cryogenic freezing of Campylobacter species in ground Turkey patties treated with polyphosphates.

    Science.gov (United States)

    Gunther Iv, Nereus W; Rajkowski, Kathleen T; Sommers, Christopher

    2015-02-01

    The use of polyphosphate-based marinades in the processing of poultry has been previously shown to increase the survival of Campylobacter species present in the exudates derived from these products. This study investigates the effects that some of the same polyphosphates have on the survival of Campylobacter species within a ground turkey product subjected to cryogenic freezing. Ground turkey patties with two different polyphosphate formulations added in two different concentrations were artificially contaminated with known concentrations of Campylobacter jejuni or Campylobacter coli. The patties were cryogenically frozen at -80F (-62.2C) with liquid nitrogen vapor and held at -20C for 7 or 33 days, after which the number of Campylobacter surviving in the patties was determined. On average the cryogenic freezing resulted in a 2.5-log decrease in the survival of C. jejuni cells and a 2.9-log decrease in C. coli cells present in the turkey patties. Additionally, the presence of polyphosphates in the turkey patties had no effect on Campylobacter survival up to the maximum allowed concentration (0.5%) for polyphosphates in poultry marinades. Finally, it was determined that the added polyphosphates had little effect on the pH of the ground turkey meat; an effect which previously had been implicated in the enhancement of Campylobacter survival due to the presence of polyphosphates. PMID:25710161

  16. Effects of pentachlorophenol on survival of earthworms (Lumbricus terrestris) and phagocytosis by their immunoactive coelomocytes

    Energy Technology Data Exchange (ETDEWEB)

    Giggleman, M.A.; Fitzpatrick, L.C.; Goven, A.J. [Univ. of North Texas, Denton, TX (United States); Venables, B.J. [TRAC Labs., Denton, TX (United States)

    1998-12-01

    Earthworms, Lumbricus terrestris, exposed for 96 h to filter paper saturated with five nominal concentrations of pentachlorophenol, exhibited a 50% lethal concentration (LC50) of 25.0 {micro}g PCP/cm{sup 2} and corresponding whole worm body burden-based 50% lethal dose (LD50) of 877.7 {micro}g PCP/g dry mass. Linear regression modeling showed that worms increased body concentrations (BC = {micro}g PCP/g dry tissue mass) with increasing exposure concentrations (EC) according to BC = 113.5 + 29.5EC. Phagocytosis of yeast cells by immunoactive coelomocytes was suppressed only at body concentrations (863.3 {micro}g PCP/g dry mass) that approximated the calculated LD50 and overlapped those demonstrating lethality, indicating a sharp transition between sublethal and lethal toxicity. An exposure concentration of 15 {micro}g PCP/cm{sup 2} produced significant suppression of phagocytosis of yeast cells by immunoactive coelomocytes. However, the average measured body burden from this group approximated the estimated LD50, indicating a sharp toxic response slope. Exposure to 10 {micro}g PCP/cm{sup 2} with a corresponding body concentration of 501.3 {micro}g PCP/g dry mass did not affect phagocytosis. The importance of body burden data is emphasized.

  17. Survival and fertility of boar spermatozoa after freeze-thawing in extender supplemented with butylated hydroxytoluene.

    Science.gov (United States)

    Roca, Jordi; Gil, Maria A; Hernandez, Marta; Parrilla, Inma; Vazquez, Juan M; Martinez, Emilio A

    2004-01-01

    This study evaluated the protective effect of butylated hydroxytoluene (BHT), a lipid-soluble antioxidant, against cryopreservation injuries to boar spermatozoa. In experiment 1, the lowest BHT concentrations able to reduce lipid peroxidation in boar spermatozoa were determined. Nine BHT concentrations (ranging from 0.025 to 3.2 mM) were evaluated, and the lowest (P survivability was evaluated when BHT was added to a postthaw freezing extender by measuring the degree of sperm lipid peroxidation (using MDA production) and by measuring parameter such as motility, plasma membrane and acrosome integrity, and cell apoptosis. The ability of thawed spermatozoa to fertilize in vitro-matured oocytes and of embryos to develop to the blastocyst stage in vitro was also assessed. Pooled sperm-rich fractions collected from 3 mature Pietrain boars were frozen in 0.5-mL straws after dilution with lactose-egg yolk-glycerol-Orvus ES Paste extender supplemented with 0, 0.2, 0.4, 0.8, and 1.6 mM BHT. Postthaw sperm survival, evaluated 30 and 150 minutes after thawing, was higher in BHT-treated spermatozoa, being significant (P extender was supplemented with 0.2, 0.4, and 0.8 mM BHT. The addition of BHT to the freezing extender resulted in a significant (P spermatozoa, irrespective of the level of BHT used. BHT had no effect on oocyte cleavage rates, but the development to blastocyst was improved for embryos derived from spermatozoa frozen in extender supplemented with 0.4 mM BHT (16% vs 29% of blastocysts per total oocytes; P extender improved the overall efficiency of thawed boar spermatozoa. PMID:15064318

  18. Effects of sugar alcohol and proteins on the survival of Lactobacillus bulgaricus LB6 during freeze drying

    Directory of Open Access Journals (Sweden)

    He Chen

    2015-06-01

    Full Text Available Background. Lactobacillus bulgaricus LB6 is a bacterium which was selected in the commercial yoghurt with high angiotensin converting enzyme (ACE inhibitory activity. Preparation of concentrated starter cultures via freeze drying is of practical importance to dairy and food industries. Material and methods. We optimized the optimal sugar alcohol and proteins for Lactobacillus bulgaricusLB6 during the process of freeze drying using a Plackett-Burman design. In our initial tests survival rate and the number of viable cells were associated with the type of lyoprotectant used and so our optimization protocol focused on increasing survival rate. Substances that had previously had a protective effect during freeze drying were investigated, for example: mannitol, sorbitol, xylitol, meso-erythritol, lactitol, whey protein isolate 90, bovine serum albumin, and whey protein concentrate 80 and soy protein isolate 70. Results. We found that the optimum sugar alcohol and proteins for survival of Lactobacillus bulgaricus LB6 were whey protein concentrate (p = 0.0040 for survival rate, xylitol (p = 0.0067 for survival rate and sorbitol (p = 0.0073 for survival rate, they showed positive effect (whey protein concentrate and sorbitol or negative effect (xylitol. Discussion. The effectiveness of three chosen sugar alcohols and protein implied that they could be used as lyoprotectant for Lactobacillus bulgaricus LB6 in the further research, the optimal composition of sugar alcohol and protein for the lyoprotectant use must be established.

  19. Earthworm Protease

    International Nuclear Information System (INIS)

    The alimentary tract of earthworm secretes a group of proteases with a relative wide substrate specificity. In 1983, six isozymes were isolated from earthworm with fibrinolytic activities and called fibrinolytic enzymes. So far, more isozymes have been found from different earthworm species such as Lumbricus rubellus and Eisenia fetida. For convenience, the proteases are named on the basis of the earthworm species and the protein function, for instance, Eisenia fetida protease (EfP). The proteases have the abilities not only to hydrolyze fibrin and other protein, but also activate pro enzymes such as plasminogen and prothrombin. In the light of recent studies, eight of the EfPs contain oligosaccharides chains which are thought to support the enzyme structure. Interestingly, EfP-II has a broader substrate specificity presenting alkaline trypsin, chymotrypsin and elastase activities, but EfP-III-1 has a stricter specificity. The protein crystal structures show the characteristics in their specificities. Earthworm proteases have been applied in several areas such as clinical treatment of clotting diseases, anti-tumor study, environmental protection and nutritional production. The current clinical utilizations and some potential new applications of the earthworm protease will be discussed in this paper.

  20. Soil salinity increases survival of freezing in the enchytraeid Enchytraeus albidus.

    Czech Academy of Sciences Publication Activity Database

    Patrcio Silva, A. L.; Holmstrup, M.; Ko?l, Vladimr; Amorim, M. J. B.

    2013-01-01

    Ro?. 216, ?. 14 (2013), s. 2732-2740. ISSN 0022-0949 Institutional support: RVO:60077344 Keywords : ice content * freeze tolerance * osmolality Subject RIV: ED - Physiology Impact factor: 3.002, year: 2013

  1. The effect of cryogenic freezing and gamma irradiation on the survival of Salmonella on frozen shrimp

    Science.gov (United States)

    Unfortunately, contraction of foodborne illness due to consumption of contaminated seafood, including shrimp, is an occasional occurrence. Cryogenic freezing and gamma irradiation are safe and effective technologies that can be used to control and inactivate pathogenic bacteria in foods. In this stu...

  2. Role of cold climate and freeze-thaw on the survival, transport, and virulence of Yersinia enterocolitica.

    Science.gov (United States)

    Asadishad, Bahareh; Ghoshal, Subhasis; Tufenkji, Nathalie

    2013-12-17

    Surface and near-surface soils in cold climate regions experience low temperature and freeze-thaw (FT) conditions in the winter. Microorganisms that are of concern to groundwater quality may have the potential to survive low temperature and FT in the soil and aqueous environments. Although there is a body of literature on the survival of pathogenic bacteria at different environmental conditions, little is known about their transport behavior in aquatic environments at low temperatures and after FT. Herein, we studied the survival, transport, and virulence of a Gram-negative bacterial pathogen, Yersinia enterocolitica, when subjected to low temperature and several FT cycles at two solution ionic strengths (10 and 100 mM) in the absence of nutrients. Our findings demonstrate that this bacterium exhibited higher retention on sand after exposure to FT. Increasing the number of FT cycles resulted in higher bacterial cell surface hydrophobicity and impaired the swimming motility and viability of the bacterium. Moreover, the transcription of flhD and fliA, the flagellin-encoding genes, and lpxR, the lipid A 3'-O-deacylase gene, was reduced in low temperature and after FT treatment while the transcription of virulence factors such as ystA, responsible for enterotoxin production, ail, attachment invasion locus gene, and rfbC, O-antigen gene, was increased. Y. enterocolitica tends to persist in soil for long periods and may become more virulent at low temperature in higher ionic strength waters in cold regions. PMID:24283700

  3. Freeze tolerance and accumulation of cryoprotectants in the enchytraeid Enchytraeus albidus (Oligochaeta) from Greenland and Europe

    DEFF Research Database (Denmark)

    Slotsbo, Stine; Maraldo, Kristine

    2008-01-01

    The freeze tolerance and accumulation of cryoprotectants was investigated in three geographically different populations of the enchytraeid Enchytraeus albidus (Oligochaeta). E. albidus is widely distributed from the high Arctic to temperate Western Europe. Our results show that E. albidus is freeze tolerant, with freeze tolerance varying extensively between Greenlandic and European populations. Two populations from sub Arctic (Nuuk) and high Arctic Greenland (Zackenberg) survived freezing at -15 degrees C, whereas only 30% of a German population survived this temperature. When frozen, E. albidus responded by catabolising glycogen to glucose, which likely acted as a cryoprotectant. The average glucose concentrations were similar in the three populations when worms were frozen at -2 degrees C, approximately 50 microg glucose mg(-1) tissue dry weight (DW). At -14 degrees C the glucose concentrations increased to between 110 and 170 microg mg(-1) DW in worms from Greenland. The average glycogen content of worms from Zackenberg and Nuuk were about 300 microg mg(-1) DW, but only 230 microg mg(-1) DW in worms from Germany showing that not all glycogen was catabolised during the experiment. Nuclear magnetic resonance spectrometry (NMR) was used to screen for other putative cryoprotectants. Proline, glutamine and alanine were up regulated in frozen worms at -2 degrees C but only in relatively small concentrations suggesting that they were of little significance for freeze survival. The present study confirms earlier reports that freeze tolerant enchytraeids, like other freeze tolerant oligochaete earthworms, accumulate high concentrations of glucose as a primary cryoprotectant.

  4. The effect of protective ingredients on the survival of immobilized cells of Streptococcus thermophilus to air and freeze-drying

    Scientific Electronic Library Online (English)

    Claude P., Champagne; Nancy J., Gardner.

    2001-12-15

    Full Text Available Streptococcus thermophilus cultures were grown either on trehalose or lactose, immobilized in alginate beads, dipped in various protective solutions and dried by either convection air-drying (CAD) or freeze-drying (FD). Immobilized cultures dipped in the 0.1% peptone solution did not show good survi [...] val to CAD or FD, as mortality was over 99%. There was no significant difference in mortality levels, in both methods of drying, when lactose or trehalose were used as protective ingredients. The highest survival levels (50 to 98%) were with a whey-sucrose protective medium, but this was potentially related to a higher pH and solids of the solution. Mortality levels were higher in FD than CAD, and this did not appear to be related to the fact that FD cultures had lower residual moisture contents than those dried under CAD. Cells grown on lactose had slightly higher survival rates to drying than those obtained from CAD. Trehalose-positive and trehalose-negative cultures of S. thermophilus did not show different mortality patterns to CAD or FD.

  5. Identification of Sigma Factor ?B-Controlled Genes and Their Impact on Acid Stress, High Hydrostatic Pressure, and Freeze Survival in Listeria monocytogenes EGD-e

    OpenAIRE

    Wemekamp-Kamphuis, Henrike H.; Wouters, Jeroen A.; de Leeuw, Patrick P. L. A.; Hain, Torsten; Chakraborty, Trinad; Abee, Tjakko,

    2004-01-01

    The gene encoding the alternative sigma factor ?B in Listeria monocytogenes is induced upon exposure of cells to several stresses. In this study, we investigated the impact of a sigB null mutation on the survival of L. monocytogenes EGD-e at low pH, during high-hydrostatic-pressure treatment, and during freezing. The survival of ?sigB mutant exponential-phase cells at pH 2.5 was 10,000-fold lower than the survival of EGD-e wild-type cells. Moreover, the ?sigB mutant failed to show an acid tol...

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

    International Nuclear Information System (INIS)

    Mature (clitellate) Eisenia andrei Bouche (ultra epigeic), Lumbricus rubellus Hoffmeister (epigeic), and Aporrectodea caliginosa (Savigny) (endogeic) earthworms were placed in soils treated with Pb(NO3)2 to have concentrations in the range 1000 to 10 000 mg Pb kg-1. After 28 days LC50-95%confidencelimit+95%confidencelimit values were E. andrei5824-361+898 mg Pb kg-1, L. rubellus2867-193+145 mg Pb kg-1 and A. caliginosa2747-304+239 mg Pb kg-1 and EC50s for weight change were E. andrei2841-68+150 mg Pb kg-1, L. rubellus1303-201+240 mg Pb kg-1 and A. caliginosa1208-206+212 mg Pb kg-1. At any given soil Pb concentration, Pb tissue concentrations after 28 days were the same for all three earthworm species. In a soil avoidance test there was no difference between the behaviour of the different species. The lower sensitivity to Pb exhibited by E. andrei is most likely due to physiological adaptations associated with the modes of life of the earthworms, and could have serious implications for the use of this earthworm as the species of choice in standard toxicological testing.

  7. Earthworms and Soil Pollutants

    Directory of Open Access Journals (Sweden)

    Kazuyoshi Tamae

    2011-11-01

    Full Text Available 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.

  8. Earthworms and Soil Pollutants

    OpenAIRE

    Kazuyoshi Tamae; Takeshi Hirano

    2011-01-01

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

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

    Science.gov (United States)

    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, earthw...

  10. The Resistance to Freeze-Drying and to Storage Was Determined as the Cellular Ability to Recover Its Survival Rate and Acidification Activity

    Directory of Open Access Journals (Sweden)

    Georges Lognay

    2010-01-01

    Full Text Available The protective effects of the fatty acid composition and membrane action of the acidification activity of two strains of Lactobacillus kept at 20?C were studied. The addition of sorbitol, monosodium glutamate and glycerol during storage is causing the decline of acidification and increased concentrations of unsaturated fatty acids observed in both strains. The addition of sorbitol and monosodium glutamate does not alter the fatty acid composition, whatever the strain, but increases the resistance to freeze-drying of L. plantarum CWBI-B1419 and improves survival during storage. The addition of these preservatives and decreased activity of acidification improves the ratio unsaturated. These results indicate that the survival during storage and freeze-drying resistance are closely related to the composition of membrane fatty acids. This behaviour can be interpreted as an adaptation of L. plantarum B1419-CWBI supplemented by cryoprotectant additives such as sorbitol or monosodium glutamate sorbitol and monosodium glutamate as an additive. L. plantarum CWBI-B1419 presents a greater adaptation to culture conditions than L. paracasei ssp. paracasei LMG9192T.

  11. Nutrition Studies with Earthworms.

    Science.gov (United States)

    Tobaga, Leandro

    1980-01-01

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

  12. Determination of arsenic compounds in earthworms

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-08-01

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

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

    Science.gov (United States)

    Roub?kov, Alena; Frouz, Jan

    2015-04-01

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

  14. Exposure to extremely low frequency (50 Hz electromagnetic field changes the survival rate and morphometric characteristics of neurosecretory neurons of the earthworm Eisenia foetida (Oligochaeta under illumination stress

    Directory of Open Access Journals (Sweden)

    Banova?ki Zorana

    2013-01-01

    Full Text Available An in vivo model was set up to establish the behavioral stress response (rate of survival and morphometric characteristics of A1 protocerebral neurosecretory neurons (cell size of Eisenia foetida (Oligochaeta as a result of the synergetic effect of extremely low frequency electromagnetic fields (ELF-EMF - 50 Hz, 50 ?T, 17 V/m and 50 Hz, 150 ?T, 17 V/m, respectively and constant illumination (420-450 lux. If combined, these two stressors significantly (p<0.05 increased the survival rate of E. foetida in the 150 ?T-exposed animals, because of delayed caudal autotomy reflex, an indicator of stress response. In addition, morphometric analysis indicated that there were changes in the protocerebral neurosecretory cells after exposure to the ELF-EMF. The present data support the view that short-term ELF-EMF exposure in windows of intensity is likely to stimulate the immune and neuroendocrine response of E. foetida.

  15. Pesticides and earthworms : a review

    OpenAIRE

    Pelosi, C.; Barot, Sbastien; Capowiez, Y.; Hedde, M.; F. Vandenbulcke

    2014-01-01

    Earthworms provide key soil functions that favour many positive ecosystem services. These services are important for agroecosystem sustainability but can be degraded by intensive cultural practices such as use of pesticides. Many literature reports have investigated the effect of pesticides on earthworms. Here, we review those reports to assess the relevance of the indicators of earthworm response to pesticides, to assess their sensitivity to pesticides, and to highlight the remainin...

  16. Removal of mercury from soil with earthworms

    Energy Technology Data Exchange (ETDEWEB)

    Dorfman, D. [Monmouth Coll., West Long Branch, NJ (United States)

    1994-12-31

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

  17. Cryoprotectants are metabolic fuels during long term frost exposure in the earthworm Dendrobaena octaedra.

    DEFF Research Database (Denmark)

    C. Jrgensen, Sofia; Overgaard, Johannes

    2008-01-01

    Ectothermic animals that live in the subarctic and temperate regions must have strategies to deal with periods of frost during winter. The earthworm Dendrobaena octaedra is a freeze tolerant species that accumulates large concentrations of the cryoprotectant glucose upon ice formation in the extracellular fluid. This study investigates if D. octaedra metabolizes its primary cryoprotectant as an energy source when frozen for longer periods. In this study D. octaedra were exposed to frost at 2C for 47days. The results clearly demonstrate a gradual decrease in the level of glucose and simultaneously an accumulation of lactate, alanine and succinate as a result of the continuous anaerobic metabolism. Freeze mortality (~30%) did not increase with time suggesting that the accumulation of waste products were not toxic to the worms. Instead dead worms were always characterised by low glucose and glycogen levels indicating that depletion of fermentable resources was the primary cause of death. Calorimetric measurements of metabolic rate showed a 15-fold metabolic depression in frozen versus unfrozen worms and this reduction in metabolic rate is clearly of importance for long term survival of frozen worms. On the basis of metabolic rate measurements we calculated that the average worms would be able to survive for a total of 83days before the glucose storage becomes exhausted. In conclusion, the present study suggests that the large accumulations of glucose during frost may be more important as anaerobic fuel source than as a cryoprotectant.

  18. Correlations between Lumbricus terrestris survival and gut microbiota

    OpenAIRE

    Knut Rudi; Knut Olav Strtkvern

    2012-01-01

    Background: The interplay between diet, gut bacteria and health still remain enigmatic. Here, we addressed this issue through the investigation of the effect of crystalline cellulose on the earthworm Lumbricus terrestris gut microbiota composition and survival. Methods : Earthworm gut contents were analyzed after 14 days of feeding using a mixed 16S rRNA gene sequencing approach, in addition to direct measurements of cellulase activity. The survival of earthworms was followed each week for 17...

  19. Production and utilization of earthworms as feeds for broilers in the Philippines

    Directory of Open Access Journals (Sweden)

    Barcelo P., M.

    1988-01-01

    Full Text Available A study on the production of earthworms was conducted using a 50 : 50 by volume of animal manures in combination with Leucaena leucocephala. A combination of sawdust, rice hull and rice bran at a proportion of 55, 35 and 10 respectively was also used as a substrate. The earthworms in each box were supplemented with either 0, 100, 200, 300 and 400 g kitchen scraps. On harvesting, hand picking the earthworms from the castings and arranging the contents of the box in a pyramid were tested. Blanching, direct heating, freezing and using an oven-drier were likewise tested on "killing" earthworms prior to drying. On broiler utilization, eighty four one-day old broiler chicks were fed with the six rations formulated where in 6 %, 10 % and 14 % levels of vermimeal and fish meal were used with the commercial mash as the control. Results revealed that goat manure in combination with Leucaena leucocephala with 100 to 400g feed supplement produced the highest gain and largest population. The pyramid method for harvesting and freezing for processing earthworms were found to be the best. Commercial broiler mash was significantly better than the home-mixed rations. In the home-mixed rations, 10 to 14 % levels of vermimeal were comparable to 6 % vermimeal and 6-10 % fish meal.

  20. Ketahanan dan viabilitas probiotik bakteri asam laktat selama proses pembuatan kultur kering dengan metode freeze dan spray drying [Survival and Viability of Lactid Acid Bacteria Probiotic during production of Dried Culture Using Freeze and Spray Drying Methods

    Directory of Open Access Journals (Sweden)

    Erni Harmayani 1

    2001-08-01

    Full Text Available Selection on 36 lactid aid bacteria isolate from various source (dadih, sausage, infant faces, gato, chinese leaf pickle, growol and yoghurt has been carried out based on their potency to reduce choresterol. Based on their ability to assimilate choresterol, conjugate bile solt, restency on bile salt and low pH, three isolates i.e. Lactobacillus sp. Dad 13, L. asidophillus D2 and L. plantarum Mut 7 have been chosen for further study. Viability of selected cultures during biomass production using coconut water with addition of 0.5% yeast extract, and during production of dried starter culture using freeze and spray dried were investigated. The results show that the growth patern of the three isolates selected were almost similar i.e. reaching maximum amount after 16 hours fermentation at 37C. biomass production using coconut water produced 109 cfu/ml after 16-18 hours incubation at 37C. decrease on viability after drying using freeze drier ranged between 0.5-2 log cycles, while that of storage of freeze dried culture during 4 weeks at -20C caused descreasing in viability of 26-56%.

  1. Anhydrobiosis and Freezing-Tolerance

    DEFF Research Database (Denmark)

    McGill, Lorraine; Shannon, Adam; Pisani, Davide; Felix, Marie-Anne; Ramlv, Hans; Dix, Ilona; Wharton, David; Burnell, Ann

    2015-01-01

    Anhydrobiotic animals can survive the loss of both free and bound water from their cells. While in this state they are also resistant to freezing. This physiology adapts anhydrobiotes to harsh environments and it aids their dispersal. Panagrolaimus davidi, a bacterial feeding anhydrobiotic nematode...... Panagrolaimus strains from tropical, temperate, continental and polar habitats and we analysed their phylogenetic relationships. We found that several other Panagrolaimus isolates can also survive freezing when fully hydrated and that tissue extracts from these freezing-tolerant nematodes can inhibit the growth...... common ancestors of the davidi and the superbus clades were anhydrobiotic and also possessed robust freezing tolerance, along with a capacity to inhibit the growth and recrystallization of ice crystals. Unlike other endemic Antarctic nematodes, the life history traits of P. davidi do not show evidence of...

  2. Earthworms-microfungi interactions in vermicultures.

    Czech Academy of Sciences Publication Activity Database

    Pil, Vclav; Novkov, Alena

    Cardiff : Cardiff University, 2002. s. 383. [International Symposium on Earthworm Ecology /7./. 01.09.2002-06.09.2002, Cardiff] Institutional research plan: CEZ:AV0Z6066911 Keywords : earthworms -microfungi interactions Subject RIV: EH - Ecology, Behaviour

  3. Effects of antimicrobial coatings and cryogenic freezing on survival and growth of Listeria innocua on frozen ready-to-eat shrimp during thawing

    Science.gov (United States)

    Foodborne pathogens such as Listeria monocytogenes could pose a health risk for frozen ready-to-eat (RTE) shrimp as the pathogen can grow following thawing. In this study, antimicrobial coating treatments alone, or in combination with cryogenic freezing, were evaluated for their ability to inhibit t...

  4. Mapping earthworm communities in Europe

    DEFF Research Database (Denmark)

    Rutgers, Michiel; Orgiazzi, Alberto

    Existing data sets on earthworm communities in Europe were collected, harmonized, modelled and depicted on a soil biodiversity map of Europe. Digital Soil Mapping was applied using multiple regressions relating relatively low density earthworm community data to soil characteristics, land use, vegetation and climate factors (covariables) with a greater spatial resolution. Statistically significant relationships were used to build habitat-response models for constructing earthworm maps with abundance, species richness, and diversity data. While a good number of environmental predictors were significant in our multiple regressions, geographical factors alone seem to be less relevant than climatic factors. Despite differing sampling protocols, land use and geological history were the most relevant factors determining the demography and diversity of the earthworms across Europe. Case studies from country-specific data sets (France, Germany, Ireland and The Netherlands) demonstrated the importance and efficiency oflarge databases for the detection of large spatial patterns that could be subsequently applied at smaller (local) scales. After the first set of maps, additional datasets were used to improve the regressions and maps and to extent the area depicting earthworm predictions (e.g. Portugal, Italy, England, Finland, Austria and some countries from Eastern Europe). The improved maps will be submitted for publication in the Global Soil Biodiversity Atlas.

  5. Effects of soil properties on copper toxicity to earthworm Eisenia fetida in 15 Chinese soils.

    Science.gov (United States)

    Duan, Xiongwei; Xu, Meng; Zhou, Youya; Yan, Zengguang; Du, Yanli; Zhang, Lu; Zhang, Chaoyan; Bai, Liping; Nie, Jing; Chen, Guikui; Li, Fasheng

    2016-02-01

    The bioavailability and toxicity of metals in soil are influenced by a variety of soil properties, and this principle should be recognized in establishing soil environmental quality criteria. In the present study, the uptake and toxicity of Cu to the earthworm Eisenia fetida in 15 Chinese soils with various soil properties were investigated, and regression models for predicting Cu toxicity across soils were developed. The results showed that earthworm survival and body weight change were less sensitive to Cu than earthworm cocoon production. The soil Cu-based median effective concentrations (EC50s) for earthworm cocoon production varied from 27.7 to 383.7mgkg(-1) among 15 Chinese soils, representing approximately 14-fold variation. Soil cation exchange capacity and organic carbon content were identified as key factors controlling Cu toxicity to earthworm cocoon production, and simple and multiple regression models were developed for predicting Cu toxicity across soils. Tissue Cu-based EC50s for earthworm cocoon production were also calculated and varied from 15.5 to 62.5mgkg(-1) (4-fold variation). Compared to the soil Cu-based EC50s for cocoon production, the tissue Cu-based EC50s had less variation among soils, indicating that metals in tissue were more relevant to toxicity than metals in soil and hence represented better measurements of bioavailability. PMID:26688255

  6. HOST CADAVERS PROTECT ENTOMOPATHOGENIC NEMATODES DURING FREEZING

    Science.gov (United States)

    Four species of insect-killing nematodes were exposed to freezing temperatures while inside their hosts. Survival was assessed by observing live and dead nematodes inside cadavers and by counting the infective juveniles (IJs) tht emerged after freezing. We 1) measured the effects of 24 hours of fr...

  7. New records of earthworms (Oligochaeta from Madagascar

    Directory of Open Access Journals (Sweden)

    Razafindrakoto, M.

    2010-10-01

    Full Text Available New records of earthworms from Madagascar are presented. This is the first taxonomic report on the earthwormfauna of Madagascar since the last paper of Michaelsen (1931. Altogether data on 14 peregrine earthworm species belonging tofive families are summarized. Together with the native taxa, 33 valid earthworm species have so far been recorded fromMadagascar of which 18 (55% are endemic in the Island and 15 (45% introduced.

  8. New records of earthworms (Oligochaeta) from Madagascar

    OpenAIRE

    Razafindrakoto, M.; Csuzdi, Cs.; Rakotofiringa, S.; Blanchart, E.

    2010-01-01

    New records of earthworms from Madagascar are presented. This is the first taxonomic report on the earthwormfauna of Madagascar since the last paper of Michaelsen (1931). Altogether data on 14 peregrine earthworm species belonging tofive families are summarized. Together with the native taxa, 33 valid earthworm species have so far been recorded fromMadagascar of which 18 (55%) are endemic in the Island and 15 (45%) introduced.

  9. Do alterations in mesofauna community affect earthworms?

    Science.gov (United States)

    Uvarov, Alexei V; Karaban, Kamil

    2015-11-01

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

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

    Science.gov (United States)

    Mudrák, Obdřej; Frouz, Jan

    2015-04-01

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

  11. The effect of radioecological condition to earthworms and the problems of ecosystems related with them

    International Nuclear Information System (INIS)

    The soil and fertility was evident and breathe regarding to living materials which are composed of billions of microorganisms and pedobionts also earthworms; throughout of it plants get all chemical elements. Living materials inhabit in lamella of soil, essentially within the scope of 5 to 15 cm of depth. Soil is a main source of carbon in nature. There is for about 10 times more carbone dioxide here (the breath product of soil biota) than in atmosphere. From carbonic acid of air, plants by its terrestrial part extract carbone and by the help of photosynthesis transform it to carbohydrates and tissues. Nowadays investigations about earthworms which live in strongly polluted soils has appeared that earthworms have found a way of a survival even in such extreme conditions. Earthworms have adapted to the polluted soils. However, bait attractive in appearance to dig in such places it is not necessary: in such a way the worm accumulates heavy metals in the organism. Though earthworms aren't so attractive, and for many are simply unpleasant, for an ecosystem they are invaluable. Thus even dying they don't leave after itself any traces, and digest itself by means of cages containing in them - lysis. This process is called autolysis. Thereby for investigation of strongly polluted areas of Ramana iodine plant as an ecosystem and there is significant point to determine the effect of radiation on earthworms as one of the most important chain of soil bionetwork. So, in this way it was investigated an effect of radioactive pollution to earthworms aboriginal for Absheron peninsula. By the experimentation of earthworms in contaminated soil (with 226Ra, 228Ra, U) in respectively 1 percent, 2,5 percent, 5 percent and 10 percent soil examples during a month, it was established that the earthworms so sensible to the high level of radioactive pollution. Regarding to the data received it has a point that usage of earthworms as bio indicators, in future should help people to apply this original objects in case of remediation of strongly polluted areas of Absheron peninsula.

  12. Effects of glyphosate and 2,4-D on earthworms (Eisenia foetida) in laboratory tests.

    Science.gov (United States)

    Correia, F V; Moreira, J C

    2010-09-01

    Laboratory tests were conducted to compare the effects of various concentrations of glyphosate and 2,4-D on earthworms (Eisenia foetida) cultured in Argissol during 56 days of incubation. The effects on earthworm growth, survival, and reproduction rates were verified for different exposure times. Earthworms kept in glyphosate-treated soil were classified as alive in all evaluations, but showed gradual and significant reduction in mean weight (50%) at all test concentrations. For 2,4-D, 100% mortality was observed in soil treated with 500 and 1,000 mg/kg. At 14 days, 30%-40% mortality levels were observed in all other concentrations. No cocoons or juveniles were found in soil treated with either herbicide. Glyphosate and 2,4-D demonstrated severe effects on the development and reproduction of Eisenia foetida in laboratory tests in the range of test concentrations. PMID:20658223

  13. Earthworms and their Nephridial Symbionts: Co-diversification and Maintenance of the Symbiosis

    DEFF Research Database (Denmark)

    Lund, Marie Braad; Holmstrup, Martin; Davidson, Seana K.; Schramm, Andreas

    urine; such protein recycling should therefore increase worm fitness under nitrogen-limited conditions [4]. To test this hypothesis we conducted a comparative fitness study of worms with and without symbionts; the worms were grown in soil and fed with either a nitrogen-rich or a nitrogen-poor diet. The...... suggests that the symbiosis has been stably maintained over evolutionary time dating back to the last common lumbricid earthworm ancestor. How this evolutionarily stable association is maintained is unknown; symbiont-free worms can be reared in lab culture and therefore the symbionts are not essential to...... the survival of the worms, but at the same time the symbionts are consistently found in almost all Lumbricid worm species. The symbionts have been hypothesized to be proteolytically active during excretion, thereby enhancing the earthworms absorption of nitrogenous compounds otherwise lost in the...

  14. New earthworm records from Bulgaria (Oligochaeta, Lumbricidae)

    OpenAIRE

    Szederjesi, T.

    2013-01-01

    Elaboration of a small earthworm material collected in different parts of Bulgaria resulted in recording altogether 15 species. Surprisingly, the peregrine Dendrobaena veneta veneta proved to be new to the fauna of Bulgaria and with this, the present list of Bulgarian earthworms consists of 42 confirmed species and subspecies.

  15. Metal accumulation in earthworms inhabiting floodplain soils

    Energy Technology Data Exchange (ETDEWEB)

    Vijver, Martina G. [Institute of Ecological Science, Dept. Animal Ecology, Vrije Universiteit, Amsterdam (Netherlands) and Institute for Inland Water Management and Waste Water Treatment (RIZA), Dept. Chemistry and Ecotoxicology, Lelystad (Netherlands)]. E-mail: vijver@cml.leidenuniv.nl; Vink, Jos P.M. [Institute for Inland Water Management and Waste Water Treatment (RIZA), Dept. Chemistry and Ecotoxicology, Lelystad (Netherlands); Miermans, Cornelis J.H. [Institute for Inland Water Management and Waste Water Treatment (RIZA), Dept. Chemistry and Ecotoxicology, Lelystad (Netherlands); Gestel, Cornelis A.M. van [Institute of Ecological Science, Dept. Animal Ecology, Vrije Universiteit, Amsterdam (Netherlands)

    2007-07-15

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

  16. Metal accumulation in earthworms inhabiting floodplain soils

    International Nuclear Information System (INIS)

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

  17. Carbohydrate and lipid dynamics in wheat crown tissue in response to mild freeze-thaw treatments

    Science.gov (United States)

    Freezing tolerance resulting from cold hardening is critical to survival of fall-planted crops such as winter wheat. Exposure of winter wheat plants to cycles of freeze-thaw at temperatures just below, and just above freezing results in incremental improvements of freezing tolerance. Defining the ph...

  18. Earthworm introduction on calcareous minesoils

    International Nuclear Information System (INIS)

    Burrowing activity of the nightcrawler, Lumbricus terrestis (L.t.), incorporates organic matter into mineral soil while creating long-lasting macropores. Thus L.t. has potential as a biological means of improving physical and chemical properties of surface mined areas. Efforts to establish L.t. population on forested acidic or calcareous minesoils have been successful, but thus far have not been able to establish L.t. in grassland ecosystems on calcareous minesoils. In May, 1989, the authors put 11 clitellate L.t. under sphagnum moss on calcareous gray cast overburden on standard graded topsoil, or on ripped and disked topsoil. All soils had cover of agronomic grasses and legumes. They found no L.t. at the 24 points of inoculation during sampling in fall of 1990 with formalin extractant, although smaller species, Lumbricus rubellus and Dendrobaena spp., were found. At another location, in May, 1990, they put 25 clitellate L.t. at 16 points in grasslands growing on gray cast overburden. Using formalin extraction, they found no L.t. in May 1992 at these locations. Working in this same area in November, 1992, they released 10 clitellate L.t. at 16 points under 10 cm of moist Alnus glutinosa leaf litter. Careful examination of the surface inoculation points in spring and fall of 1993 did not show obvious signs of earthworm activity. Their next step will be to use Earthworm Inoculation Units (earthworm-minesoil microcosms containing L.t. adults, immatures, and cocoons) as the source of the new populations

  19. Earthworms good indicators for forest disturbance

    Directory of Open Access Journals (Sweden)

    YAHYA KOOCH

    2014-08-01

    Full Text Available In temperate forests, formation of canopy gaps by windthrow is a characteristic natural disturbance event. Little work has been done on the effects of canopy gaps on soil properties and fauna, especially earthworms as ecosystem engineers. We conducted a study to examine the reaction of earthworms (density/biomass and different soil properties (i.e., soil moisture, pH, organic matter, total N, and available Ca to different canopy gap areas in 25-ha areas of Liresar district beech forest located in a temperate forest of Mazandaran province in the north of Iran. Soil samples were taken at 0-15, 15-30 and 30-45 cm depths from gap center, gap edge and closed canopy using core soil sampler with 81 cm2 cross section. The earthworms were collected simultaneously with the soil sampling by hand sorting method. Our study supports that the canopy gap will create a mosaic of environmental conditions. Earthworm's density and biomass tended to be higher in small canopy gaps compared with the other canopy gap areas. Earthworm's population showed decreasing trend from closed canopy to disturbed sites (gap edge and gap center. The top soil was more appropriate to presence of earthworms although ecological groups have occupied different soil layers. As a conclusion, earthworms can be introduced as good bio-indicator of environmental changes that occur by disturbance.

  20. Accumulation of chlorinated benzenes in earthworms

    Science.gov (United States)

    Beyer, W.N.

    1996-01-01

    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.

  1. Freezing and Food Safety

    Science.gov (United States)

    ... Standard Forms FSIS United States Department of Agriculture Food Safety and Inspection Service About FSIS District Offices Careers ... Viewer (JSR 286) Actions ${title} Loading... Freezing and Food Safety What Can You Freeze? Is Frozen Food Safe? ...

  2. A SMA Actuated Earthworm-Like Robot

    Science.gov (United States)

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

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

  3. Unique metabolites protect earthworms against plant polyphenols.

    Science.gov (United States)

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

    2015-01-01

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

  4. Earthworm tolerance to residual agricultural pesticide contamination

    DEFF Research Database (Denmark)

    Givaudan, Nicolas; Binet, Franoise; Le Bot, Barbara; Wiegand, Claudia

    This study investigates if acclimatization to residual pesticide contamination in agricultural soils is reflected in detoxification, antioxidant enzyme activities and energy budget of earthworms. Five fields within a joint agricultural area exhibited different chemical and farming histories from...

  5. Tracking earthworm communities from soil DNA

    OpenAIRE

    Bienert, F.; De Danieli, S.; Miquel, C.; Coissac, E.; Poillot, C.; Brun, J.J.; Taberlet, P.

    2012-01-01

    Earthworms are known for their important role within the functioning of an ecosystem, and their diversity can be used as an indicator of ecosystem health. To date, earthworm diversity has been investigated through conventional extraction methods such as handsorting, soil washing or the application of a mustard solution. Such techniques are time consuming and often difficult to apply. We showed that combining DNA metabarcoding and next-generation sequencing facilitates the identification of ea...

  6. Earthworms good indicators for forest disturbance

    OpenAIRE

    YAHYA KOOCH; KATAYOUN HAGHVERDI

    2014-01-01

    In temperate forests, formation of canopy gaps by windthrow is a characteristic natural disturbance event. Little work has been done on the effects of canopy gaps on soil properties and fauna, especially earthworms as ecosystem engineers. We conducted a study to examine the reaction of earthworms (density/biomass) and different soil properties (i.e., soil moisture, pH, organic matter, total N, and available Ca) to different canopy gap areas in 25-ha areas of Liresar district beech forest loca...

  7. Biochemical diversity of betaines in earthworms

    Energy Technology Data Exchange (ETDEWEB)

    Liebeke, Manuel [Department of Surgery and Cancer, Imperial College London, Sir Alexander Fleming Building, London SW7 2AZ (United Kingdom); Bundy, Jacob G., E-mail: j.bundy@imperial.ac.uk [Department of Surgery and Cancer, Imperial College London, Sir Alexander Fleming Building, London SW7 2AZ (United Kingdom)

    2013-01-25

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

  8. Biochemical diversity of betaines in earthworms

    International Nuclear Information System (INIS)

    Highlights: ? We develop a method for rapid untargetted analysis of betaines. ? We profile betaines in a comparative study of ten earthworm species. ? Earthworms contain a surprisingly high number of different betaine metabolites. ? Earthworms contain betaines normally seen only in plants or marine animals. -- Abstract: The ability to accumulate osmoprotectant compounds, such as betaines, is an important evolutionary feature in many organisms. This is particularly the case for organisms that live in variable environments, which may have fluctuations in moisture and salinity levels. There is, surprisingly, very little known about betaines in soil invertebrates in general, and there is almost no information about earthworms a group that are important ecosystem engineers and key indicators of soil health. Here, we describe a fast and reliable 1H13C heteronuclear single quantum coherence (HSQC) 2D NMR approach for the metabolic profiling of a series of betaines and related metabolites in tissue extracts, and list 1H and 13C chemical shifts for the trimethylammonium signal for 23 such compounds. The analysis of ten different species from three different families (Lumbricidae, Megascolecidae and Glossoscolecidae) showed an unexpected diversity of betaines present in earthworms. In total ten betaines were identified, including hydroxyproline-betaine, proline-betaine, taurine-betaine, GABA-betaine and histidine-betaine, and a further eleven as-yet unassigned putative betaine metabolites detected. The findings clearly indicate a hitherto-unappreciated important role for betaine metabolism in earthworms

  9. Cryopreservation of rabbit semen: comparing the effects of different cryoprotectants, cryoprotectant-free vitrification, and the use of albumin plus osmoprotectants on sperm survival and fertility after standard vapor freezing and vitrification.

    Science.gov (United States)

    Rosato, Maria Pina; Iaffaldano, Nicolaia

    2013-02-01

    This study was designed to improve current freezing protocols for rabbit sperm by examining: (1) the toxicity of different permeable cryoprotectants (CPAs) used for standard vapor freezing (conventional freezing); (2) the feasibility of ultrarapid nonequilibrium freezing (vitrification) of sperm in the absence of permeating CPAs; and (3), the addition of bovine serum albumin (BSA), alone or with sucrose or trehalose as osmoprotectants. First, we evaluated the effects on sperm motility of the incubation time (5 to 60 minutes) with different final concentrations (5% to 20%) of glycerol, N-N-dimethylacetamide, dimethylsulfoxide (DMSO), ethylene glycol, propylene glycol, and methanol. N-N-dimethylacetamide (5%) and DMSO (5% and 10%) showed the least toxic effects; the use of 10% DMSO producing the best postthaw sperm motility and membrane integrity results (P pregnant, though no kids were delivered. The conclusions to be drawn from our study are: (1) incubation times and concentration toxicities established for the main permeable CPAs used for conventional freezing of rabbit sperm indicated that DMSO 10% was the least damaging; (2) CPA-free vitrification of rabbit semen led to a low or null sperm cryosurvival; and (3) enriching the freezing medium with BSA plus adequate amounts of sucrose or trehalose can improve the cryosurvival of rabbit sperm after conventional freezing or vitrification. In our working conditions, BSA/sucrose was more effective than BSA/trehalose at preserving the in vivo fertilization capacity of rabbit sperm cryopreserved using the standard procedure. PMID:23218394

  10. Rediscovery of Fimoscolex sporadochaetus Michaelsen 1918 (Clitellata: Glossoscolecidae, and considerations on the endemism and diversity of Brazilian earthworms

    Directory of Open Access Journals (Sweden)

    Samuel W. JAMES

    2010-01-01

    Full Text Available Brazil hosts approximately 305 earthworm species, of which 260 (85% are native and 46 (15% exotic. Most of the native species (80% are known from only one or a few sites, and two species were considered as extinct by the Ministry of Environment of Brazil in 2003, due to lack of sightings, habitat destruction and a limited prior known distribution (endemism. One of these, Fimoscolex spora-dochaetus Michaelsen, 1918 was recently found in a forest reserve (Parque Estadual do Itacolomi, near the reservoir Bacio do Custdio in Ouro Preto, Minas Gerais. With this finding, and based on earthworm collection data in Brazil up to now, we believe that the endangered and "extinct" species should have their status reviewed, and that further collecting efforts are urgently necessary to adequately determine the extent of earthworm biodiversity in Brazil and the present level of threat to their survival.

  11. Earthworms and their Nephridial Symbionts: Co-diversification and Maintenance of the Symbiosis

    DEFF Research Database (Denmark)

    Lund, Marie Braad; Holmstrup, Martin

    Earthworms harbor in their nephridia (excretory organs) symbiotic bacteria which densely colonize a specific part of the nephridia, called the ampulla [1]. The symbiosis is species-specific and the symbionts form their own monophyletic genus Verminephrobacter (?-proteobacteria) [2] and are vertically transmitted [3]. For these reasons we hypothesized that the earthworm-Verminephrobacter association evolved by co-diversification. This hypothesis was investigated by a comparison of earthworm and symbiont phylogenies. The earthworm phylogeny was based on Cytochrome c oxidase subunit I (COI) and Histone H3 and the symbiont phylogeny was based on 16S rRNA gene sequences and RNA polymerase ? subunit (rpoB). The phylogenies were found to be largely congruent, however, leaving possibility for horizontal symbiont transfer events. In addition symbiont losses have occurred. The overall congruency suggests that the symbiosis has been stably maintained over evolutionary time dating back to the last common lumbricid earthworm ancestor. How this evolutionarily stable association is maintained is unknown; symbiont-free worms can be reared in lab culture and therefore the symbionts are not essential to the survival of the worms, but at the same time the symbionts are consistently found in almost all Lumbricid worm species. The symbionts have been hypothesized to be proteolytically active during excretion, thereby enhancing the earthworms absorption of nitrogenous compounds otherwise lost in the urine; such protein recycling should therefore increase worm fitness under nitrogen-limited conditions [4]. To test this hypothesis we conducted a comparative fitness study of worms with and without symbionts; the worms were grown in soil and fed with either a nitrogen-rich or a nitrogen-poor diet. The experiment showed no significant differences in growth rate and fecundity between symbiotic and aposymbiotic worms. Thus the symbionts do not appear to have an effect on worm fitness, under growth conditions tested. The underlying functional and maintaining mechanisms of this symbiosis remain a conundrum. [1] Knop,J. 1926. Z Morph kol Tiere, 6(3):588-624. [2] Schramm,A. et al. 2003. Environ Microbiol 5(9):804-809. [3] Davidson,S.K. & Stahl,D.A. 2006. Appl Environ Microbiol 72(1):769-775. [4] Pandazis,G. 1931. Zentralbl Bakteriol 120:440-453.

  12. Metabolic changes during estivation in the common earthworm Aporrectodea caliginosa

    DEFF Research Database (Denmark)

    Bayley, Mark; Overgaard, Johannes; Hj, Andrea Sdergaard; Malmendal, Anders; Nielsen, Niels Chr; Holmstrup, Martin; Wang, Tobias

    2011-01-01

    The common earthworm Aporrectodea caliginosa survives drought by forming estivation chambers in the topsoil under even very slight reductions in soil water activity. We induced estivation in a soil of a consistency that allowed the removal of intact soil estivation chambers containing a single worm....... These estivation chambers were exposed to 97% relative humidity for 30 d to simulate the effect of a severe summer drought. Gas exchange, body fluid osmolality, water balance, urea, and alanine were quantified, and whole-body homogenates were screened for changes in small organic molecules via (1)H......-nuclear magnetic resonance (NMR). Formation of estivation chambers was associated with a dramatic increase in body fluid osmolality, from 175 to 562 mOsm kg(-1), accompanied by a 20% increase in water content. Dehydration for 1 mo caused a further increase to 684 mOsm kg(-1), while the worms lost 50% of their...

  13. Freeze drying method

    Science.gov (United States)

    Coppa, Nicholas V. (Malvern, PA); Stewart, Paul (Youngstown, NY); Renzi, Ernesto (Youngstown, NY)

    1999-01-01

    The present invention provides methods and apparatus for freeze drying in which a solution, which can be a radioactive salt dissolved within an acid, is frozen into a solid on vertical plates provided within a freeze drying chamber. The solid is sublimated into vapor and condensed in a cold condenser positioned above the freeze drying chamber and connected thereto by a conduit. The vertical positioning of the cold condenser relative to the freeze dryer helps to help prevent substances such as radioactive materials separated from the solution from contaminating the cold condenser. Additionally, the system can be charged with an inert gas to produce a down rush of gas into the freeze drying chamber to also help prevent such substances from contaminating the cold condenser.

  14. Freeze drying apparatus

    Science.gov (United States)

    Coppa, Nicholas V. (Malvern, PA); Stewart, Paul (Youngstown, NY); Renzi, Ernesto (Youngstown, NY)

    2001-01-01

    The present invention provides methods and apparatus for freeze drying in which a solution, which can be a radioactive salt dissolved within an acid, is frozen into a solid on vertical plates provided within a freeze drying chamber. The solid is sublimated into vapor and condensed in a cold condenser positioned above the freeze drying chamber and connected thereto by a conduit. The vertical positioning of the cold condenser relative to the freeze dryer helps to help prevent substances such as radioactive materials separated from the solution from contaminating the cold condenser. Additionally, the system can be charged with an inert gas to produce a down rush of gas into the freeze drying chamber to also help prevent such substances from contaminating the cold condenser.

  15. The 2007 California Citrus Freeze: Vulnerability, Poverty, and Unemployment Issues of Farmworkers

    Science.gov (United States)

    Orozco, Graciela Leon

    2010-01-01

    In January of 2007, freezing temperatures destroyed citrus and vegetable crops in California. By May 2007, more than 9,000 freeze-related unemployment applications had been fled. Through face-to-face interviews, this study documents the experience of 63 farmworkers to find out how they survived the freeze and accessed services. Findings revealed

  16. Correlation of lethal concentrations of heavy metals with tissue levels of earthworms. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Gal, J.Y.; Bouche, M.B.

    1988-08-01

    The objectives of this research are: To establish the LC50 of the heavy metals cadmium, copper, arsenic, and mercury as well as a Cu/Cd mixture in a ratio equal to LC50 Cd/LC50 Cu, employing a chemically defined medium such as Aristol; To improve procedures for heavy-metal bioavailability studies in the field; To improve/develop test procedures using a chemically defined medium and food in 28-day uptake studies; To analyze the tissues of the surviving test earthworms as well as those from media of lesser concentrations, blanks, and background worm stock; To relate the LC50 concentrations of contaminants with the tissue-contaminant levels in the earthworms utilized in the toxicity test; and To develop first-generation interpretations relating soil-contaminant levels and bioavailability, and to interpret the fate and transport of heavy-metal contaminants.

  17. Earthworms as biomarkers for detecting soil pollution around swine farms in Timi? County

    Directory of Open Access Journals (Sweden)

    Crina L. Mo?neang

    2015-06-01

    Full Text Available By using several samples collected from different farms distances it can be determined the degree of farms pollution and their effects on ecosystems. In order to avoid any error the soil samples were tested in comparison with a control soil sample, used as a reference, considered animal waste pollution free. The registration of survival rate for each testing recipient and for each soil along five repeats was a critical control point of testing. The 11 identified soil types were tested in comparison with a clean reference soil, by using 275 test earthworms and 55 control earthworms. According to normality Kolmogorov- Smirnov test the mortality was analyzed and results were significant (p=0.046.

  18. Earthworm excreta attract soil springtails: laboratory experiments on Heteromurus nitidus (Collembola : Entomobryidae)

    OpenAIRE

    Salmon, Sandrine; Ponge, Jean-Franois

    2001-01-01

    Microarthropods 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. The soil collembolan (Hexapoda) Heteromurus nitidus, living in soils at pH > 5 only and thus rich in earthworms, is particularly attracted by earthworms in humus cores. The effect of earthworms on the distribution of H. nitidus can be mediated either by direct contact...

  19. Visualization of enzyme activities inside earthworm pores

    Science.gov (United States)

    Hoang, Duyen; Razavi, Bahar S.

    2015-04-01

    In extremely dynamic microhabitats as bio-pores made by earthworm, the in situ enzyme activities are assumed as a footprint of complex biotic interactions. Our study focused on the effect of earthworm on the enzyme activities inside bio-pores and visualizing the differences between bio-pores and earthworm-free soil by zymography technique (Spohn and Kuzyakov, 2013). For the first time, we aimed at quantitative imaging of enzyme activities in bio-pores. Lumbricus terrestris L. was placed into transparent box (152015cm). After two weeks when bio-pore systems were formed by earthworms, we visualized in situ enzyme activities of five hydrolytic enzymes (?-glucosidase, cellobiohydrolase, chitinase, xylanase, leucine-aminopeptidase, and phosphatase. Zymography showed higher activity of ?-glucosidase, chitinase, xylanase and phosphatase in biopores comparing to bulk soil. However, the differences in activity of cellobiohydrolase and leucine aminopeptidase between bio-pore and bulk soil were less pronounced. This demonstrated an applicability of zymography approach to monitor and to distinguish the in situ activity of hydrolytic enzymes in soil biopores.

  20. Earthworms (Lumbricidae) of the Bohemian Forest.

    Czech Academy of Sciences Publication Activity Database

    Pil, Vclav

    2002-01-01

    Ro?. 8, - (2002), s. 143-148. ISSN 1211-7420 R&D Projects: GA ?R GA206/99/1410; GA ?R GA206/99/1416; GA MP SE/610/10/00 Institutional research plan: CEZ:AV0Z6066911 Keywords : soil fauna * earthworms * umava Mts. Subject RIV: EH - Ecology, Behaviour

  1. Interactions between soil algae and earthworms.

    Czech Academy of Sciences Publication Activity Database

    Lukeov, Alena; Pil, Vclav

    ?esk Bud?jovice : Institute of Soil Biology BC AS CR, 2009. s. 49. [Central European Workshop on Soil Zoology /10./. 21.04.2009-24.04.2009, ?esk Bud?jovice] Institutional research plan: CEZ:AV0Z60660521 Keywords : earthworms * soil algae Subject RIV: EH - Ecology, Behaviour

  2. Soil fauna research in Poland: earthworms (Lumbricidae

    Directory of Open Access Journals (Sweden)

    Pączka Grzegorz

    2015-06-01

    Full Text Available Living organisms are the foundation of ecosystem services. Of particular notice is zooedaphone, often underestimated and basically unknown to the general public. The present review summarizes the current state of knowledge related to earthworms occurring in natural and anthropogenically altered habitats in Poland, in the context of the requirement for protection of soil biodiversity.

  3. Basic Research Tools for Earthworm Ecology

    International Nuclear Information System (INIS)

    Earthworms are responsible for soil development, recycling organic matter and form a vital component within many food webs. For these and other reasons earthworms are worthy of investigation. Many technologically-enhanced approaches have been used within earthworm-focused research. These have their place, may be a development of existing practices or bring techniques from other fields. Nevertheless, let us not overlook the fact that much can still be learned through utilisation of more basic approaches which have been used for some time. New does not always equate to better. Information on community composition within an area and specific population densities can be learned using simple collection techniques, and burrowing behaviour can be determined from pits, resin-insertion or simple mesocosms. Life history studies can be achieved through maintenance of relatively simple cultures. Behavioural observations can be undertaken by direct observation or with low cost we became usage. Applied aspects of earthworm research can also be achieved through use of simple techniques to enhance population development and even population dynamics can be directly addressed with use of relatively inexpensive, effective marking techniques. This paper seeks to demonstrate that good quality research in this sphere can result from appropriate application of relatively simple research tools.

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

    International Nuclear Information System (INIS)

    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

  5. Bacterial Diversity in the Digestive Tract of Earthworms (Oligochaeta

    Directory of Open Access Journals (Sweden)

    Hortensia Brito-Vega

    2009-01-01

    Full Text Available Anecic, epigeous and endogeous earthworms stimulate or inhibit the growth of bacteria of agricultural importance inside their digestive tracts. It is possible that these bacteria establish a mutual symbiosis within the digestive tract of the earthworm. The bacterial species reported within the intestines of the earthworms belong to the genuses Bacillus, Aeromonas, Pseudomonas, Flavobacterium, Nocardia, Gordonia, Vibrio, Clostridium, Proteus, Serratia, Mycobacterium, Klebsiella, Azotobacte and Enterobacter. These bacteria inhabit the soil and develop considerably when there are easily degradable organic soil nutrients. The bacterial community inside the digestive tract of earthworms pertains to at least four physiological groups: plant growth promoters, free-living nitrogen fixers, biocides and phosphate solubilizers. The diversity of bacterial communities within the digestive tracts of earthworms depends on climate, soil type and organic matter. The objective of this present study was to analyze the state of art on the bacterial diversity within the digestive tracts of earthworms.

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

    Science.gov (United States)

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

    2014-10-01

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

  7. Diversity of earthworms (Oligochaeta: Lumbricidae in Sofia Plain, Bulgaria

    Directory of Open Access Journals (Sweden)

    Hristo

    2014-10-01

    Full Text Available A rich earthworm material from 47 different localities in Sofia Plain has been elaborated. During the investigations between the years 2010 and 2013, thirteen earthworm species and subspecies were collected altogether, belonging to seven genera. Among them, three new records are reported. Aporrectodea longa (Ude, 1885, Eisenia lucens (Waga, 1857 and Octodrilus transpadanus (Rosa, 1884 proved to be new to the earthworm fauna of Sofia plain.

  8. Do earthworms increase N2O emissions in ploughed grassland?

    OpenAIRE

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

    2007-01-01

    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 of earthworm density, soil moisture, tillage activity and residue loads. We quantified the effect of earthworm presen...

  9. Earthworm eco-physiological characteristics and quantification of earthworm feeding in vermifiltration system for sewage sludge stabilization using stable isotopic natural abundance

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiaowei; Xing, Meiyan, E-mail: lixiaowei419@163.com; Yang, Jian; Dai, Xiaohu

    2014-07-15

    Highlights: Earthworm growth biomass and activity decreased with the VF depth. Earthworm gut microbial communities were dominated by Gammaproteobacteria. ?{sup 15}N and ?{sup 13}C in earthworms decreased with time, and increased with the VF depth. Effect of earthworm feeding in enhanced VSS reduction was analyzed quantitatively. Earthworm feeding had low contribution to the enhanced VSS reduction. - Abstract: Previous studies showed that the presence of earthworm improves treatment performance of vermifilter (VF) for sewage sludge stabilization, but earthworm eco-physiological characteristics and effects in VF were not fully investigated. In this study, earthworm population, enzymatic activity, gut microbial community and stable isotopic abundance were investigated in the VF. Results showed that biomass, average weight, number and alkaline phosphatase activity of the earthworms tended to decrease, while protein content and activities of peroxidase and catalase had an increasing tendency as the VF depth. Earthworm gut microbial communities were dominated by Gammaproteobacteria, and the percentages arrived to 7692% of the microbial species detected. {sup 15}N and {sup 13}C natural abundance of the earthworms decreased with operation time, and increased as the VF depth. Quantitative analysis using ?{sup 15}N showed that earthworm feeding and earthwormmicroorganism interaction were responsible for approximately 21% and 79%, respectively, of the enhanced volatile suspended solid reduction due to the presence of earthworm. The finding provides a quantitative insight into how earthworms influence on sewage sludge stabilization in vermifiltration system.

  10. Freeze-drying of lactic acid bacteria.

    Science.gov (United States)

    Fonseca, Fernanda; Cenard, Stphanie; Passot, Stphanie

    2015-01-01

    Lactic acid bacteria are of great importance for the food and biotechnology industry. They are widely used as starters for manufacturing food (e.g., yogurt, cheese, fermented meats, and vegetables) and probiotic products, as well as for green chemistry applications. Freeze-drying or lyophilization is a convenient method for preservation of bacteria. By reducing water activity to values below 0.2, it allows long-term storage and low-cost distribution at suprazero temperatures, while minimizing losses in viability and functionality. Stabilization of bacteria via freeze-drying starts with the addition of a protectant solution to the bacterial suspension. Freeze-drying includes three steps, namely, (1) freezing of the concentrated and protected cell suspension, (2) primary drying to remove ice by sublimation, and (3) secondary drying to remove unfrozen water by desorption. In this chapter we describe a method for freeze-drying of lactic acid bacteria at a pilot scale, thus allowing control of the process parameters for maximal survival and functionality recovery. PMID:25428024

  11. Dynamics of earthworms in some Colombian Andean hillsides

    International Nuclear Information System (INIS)

    Samples were taken from 40 year old forest and from Pennisetum clandestinum pastures in hillside soil, with the aim of determining the temporal dynamics of earthworm diversity, abundance and biomass. The methodology consisted in manually taking two soil samples per week of a volume of 1 x 1 x 0.6 m each. The parameters vary depending on land use and time of sampling. In total 17 earthworm species were found in the soil. Earthworm diversity and biomass were higher in S+40 years than in P. clandestinum (11 vs 9), while earthworm density was higher in P. clandestinum

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

    Science.gov (United States)

    Morris, D E; Pivnick, K A

    1991-11-01

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

  13. ECOTOXICOLOGICAL BIOASSAYS OF THE EARTHWORMS ALLOLOBOPHORA CALIGINOSA SAVIGNY AND PHERETIMA HAWAYANA ROSA TREATED WITH ARSENATE

    Directory of Open Access Journals (Sweden)

    Abdelmonem Mohamed Khalil

    2013-01-01

    Full Text Available Little research has been carried out on the effect of arsenate on earthworms. Ecotoxicological laboratory tests are fundamental tools for assessing the toxicity of arsenate to soil organisms. In this study, the impact of arsenate on the survival, reproduction and behaviour of the endogenic earthworms Allolobophora caliginosa and the anecic earthworms Pheretima hawayana has been quantified. The 96-h LC 50 of arsenate was estimated as 233.43 mg arsenate Kg-1 soil. d.w. for P. hawayana which is significantly higher than that of A. caliginosa 147.2427.16 mg arsenate kg-1 soil d.w. The number of juveniles of P. hawayana was significantly higher than that of A. caliginosa at the arsenate concentrations 180, 240 and 400 mg kg-1 soil dry weight. With the exception of the control (6.5 mg arsenate kg-1 soil.d.w., P. hawayana showed an avoidance behaviour for soils treated with all tested concentrations. A. caliginosa preferred soils treated with 6.5, 60, 110, 180 mg arsenate kg-1 soil d.w., while the avoidance behaviour has been recorded only at 240 and 400 mg arsenate kg-1 soil. d.w. This means that A. caliginosa individuals feed less when exposed to arsenate. On the contrary, the P. hawayana worms could be escaped into their deep vertical burrows when exposed to arsenate.

  14. Sensing microorganisms in the gut triggers the immune response in Eisenia andrei earthworms.

    Science.gov (United States)

    Dvo?k, Ji?; Roubalov, Radka; Prochzkov, Petra; Rossmann, Pavel; kanta, Frantiek; Bilej, Martin

    2016-04-01

    The tube-within-tube body plan of earthworms is appropriate for studying the interactions of microorganisms with the immune system of body cavities such as the digestive tract and coelom. This study aims to describe the immune response on the molecular and cellular level in the coelomic cavity and the gut of the earthworm Eisenia andrei after experimental microbial challenge by administering two bacterial strains (Escherichia coli and Bacillus subtilis) or yeast Saccharomyces cerevisiae to the environment. The changes in mRNA levels of defense molecules (pattern recognition receptor CCF, lysozyme, fetidin/lysenins) in the coelomocytes and gut tissue were determined by quantitative PCR. The immune response at a cellular level was captured in histological sections, and the expression of CCF was localized using in situ hybridization. Coelomocytes respond to the presence of bacteria in the coelomic cavity by increasing the mRNA levels of defense molecules, especially CCF. The immune response in gut tissue is less affected by microbial stimulation because the epithelial cells of gut exhibit basically strong mRNA synthesis of ccf as a defense against the continuous microbial load in the gut lumen. The cellular immune response is mediated by coelomocytes released from the mesenchymal lining of the coelomic cavity. These combined immune mechanisms are necessary for the survival of earthworms in the microbially rich environment of soil. PMID:26684064

  15. Impact of a changed inundation regime caused by climate change and floodplain rehabilitation on population viability of earthworms in a lower River Rhine floodplain.

    Science.gov (United States)

    Thonon, Ivo; Klok, Chris

    2007-01-01

    River floodplains are dynamic and fertile ecosystems where soil invertebrates such as earthworms can reach high population densities. Earthworms are an important food source for a wide range of organisms including species under conservation such as badgers. Flooding, however, reduces earthworm numbers. Populations recover from cocoons that survive floods. If the period between two floods is too short such that cocoons cannot develop into reproductive adults, populations cannot sustain themselves. Both climate change and floodplain rehabilitation change the flooding frequency affecting earthworm populations. The present paper estimates the influence of climate change and floodplain rehabilitation on the viability of earthworm populations in a Dutch floodplain; the Afferdensche and Deestsche Waarden along the River Waal. This floodplain will be part of major river rehabilitation plans of the Dutch government. In those plans, the floodplain will experience the construction of a secondary channel and the removal of part of its minor embankment. To estimate the impact of these plans and climate change, we used a dataset of daily discharges for 1900-2003 for the River Rhine at the Dutch-German border. We perturbed this dataset to obtain two new datasets under climate change scenarios for 2050 and 2100. From the original and two projected datasets we derived the frequency distributions for the annual periods without inundations for the studied floodplain. We subsequently compared the duration of these inundation-free (dry) periods with the maturation age distribution for L. rubellus as derived from a Dynamic Energy Budget model. This comparison yielded in which parts of our study area and under which climate conditions the populations would still be viable, be able to adapt or become extinct. The results show that climate change has almost no adverse effect on earthworm viability. This is because climate change reduces the flooding frequency during the earthworms growing season. Floodplain rehabilitation, on the other hand, reduces the part of the floodplain area where populations can sustain themselves. Before rehabilitation, only 12% of the floodplain area cannot sustain a viable earthworm population. After rehabilitation, this increases to 59%, 28% of which is due to more frequent flooding. Enhanced exposure to soil contaminants may further suppress earthworm viability. This could frustrate further nature development and the viability of earthworm-dependent species such as the badger (Meles meles) or little owl (Athene noctua vidalli species), which is an objective of the river rehabilitation plans in the Netherlands. PMID:17140641

  16. Ecological transfer of radionuclides and metals to free-living earthworm species in natural habitats rich in NORM

    International Nuclear Information System (INIS)

    Transfer of radionuclides (232Th and 238U) and associated metals (As, Cd, Pb and Cr) from soil to free-living earthworm species was investigated in a thorium (232Th) rich area in Norway. Sampling took place within former mining sites representing the technologically enhanced naturally occurring radioactive materials (TENORM), at undisturbed site with unique bedrock geology representing the naturally occurring radioactive materials (NORM) and at site outside the 232Th rich area taken as reference Background site. Soil analysis revealed the elevated levels of investigated elements at NORM and TENORM sites. Based on sequential extraction, uranium (238U) and cadmium (Cd) were quite mobile, while the other elements were strongly associated with mineral components of soil. Four investigated earthworm species (Aporrectodea caliginosa, Aporrectodea rosea, Dendrodrilus rubidus and Lumbricus rubellus) showed large individual variability in the accumulation of radionuclides and metals. Differences in uptake by epigeic and endogeic species, as well as differences within same species from the NORM, TENORM and Background sites were also seen. Based on total concentrations in soil, the transfer factors (TF) were in ranges 0.030.08 and 0.090.25, for 232Th and 238U, respectively. TFs for lead (Pb), chromium (Cr) and arsenic (As) were low (less than 0.5), while TFs for Cd were higher (about 10). Using the ERICA tool, the estimated radiation exposure dose rate of the earthworms ranged from 2.2 to 3.9 ?Gy/h. The radiological risk for investigated earthworms was low (0.28). The obtained results demonstrated that free-living earthworm species can survive in soil containing elevated 232Th and 238U, as well As, Cd, Pb and Cr levels, although certain amount of radionuclides was accumulated within their bodies. The present investigation contributes to general better understanding of complex soil-to-biota transfer processes of radionuclides and metals and to assessment of risk for non-human species in the ecosystem with multiple contaminants. - Highlights: ? Transfer of radionuclides (232Th, 238U) and metals (As, Cr, Cd and Pb) from soil to earthworms was investigated. ? Individual organisms variability and species specific accumulation were demonstrated. ? Results suggested that earthworms could survive in habitats with multiple contaminants. ? Estimated radiological risk was not significant despite high soil concentrations of radionuclides.

  17. Contact tests for pentachlorophenol toxicity to earthworms

    Energy Technology Data Exchange (ETDEWEB)

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

    1994-12-31

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

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

    Science.gov (United States)

    Lvque, Thibaut; Capowiez, Yvan; Schreck, Eva; Mombo, Stphane; Mazzia, Christophe; Foucault, Yann; Dumat, Camille

    2015-04-01

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

  19. Earthworm communities in central European beech forests.

    Czech Academy of Sciences Publication Activity Database

    Pil, Vclav

    ?esk Bud?jovice : ISB BC AS CR, 2007, s. 103-107. ISBN 978-80-86525-08-2. [Contributions to Soil Zoology in Central Europe II. Central European Workshop on Soil Zoology /8./. ?esk Bud?jovice (CZ), 20.04.2005-22.04.2005] Institutional research plan: CEZ:AV0Z60660521 Keywords : earthworms * communities * beech forests Subject RIV: EH - Ecology, Behaviour

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

    OpenAIRE

    GONG, PING; GUAN Xin; Pirooznia, Mehdi; Liang, Chun; Perkins, Edward J.

    2012-01-01

    The earthworm Eisenia fetida is one of the most used species in standardized soil ecotoxicity tests. Endpoints such as survival, growth and reproduction are eco-toxicologically relevant but provide little mechanistic insight into toxicity pathways, especially at the molecular level. Here we applied a toxicogenomic approach to investigate the mode of action underlying the reversible neurotoxicity of hexanitrohexaazaisowurtzitane (CL-20), a cyclic nitroamine explosives compound. We developed an...

  1. Teaching basic neurophysiology using intact earthworms.

    Science.gov (United States)

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

    2010-01-01

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

  2. Pellet freezing of in vitro produced bovine embryos using dry ice.

    Science.gov (United States)

    Otoi, T; Abdoon, A SS; Omaima, M TK; Tanaka, M; Suzuki, T

    2000-01-01

    In vitro produced bovine embryos were frozen by pellet freezing or vitrification method. In the pellet freezing method, the embryos were cooled on the dry ice and then frozen as pellets. At warming, the pellets were immersed directly into 0.5 M sucrose. The survival rates of blastocysts frozen by the pellet freezing method were higher (P<0.01) in 40% ethylene glycol (EG) than those in the lower concentrations (20 and 30% EG). Higher survival rates of blastocysts frozen by the pellet freezing method were obtained but the development rates did not differ, as compared with those by the vitrification method. There were no significant differences between the pellet freezing and vitrification method in the frequencies of post-thaw survival of hatched blastocysts. These results demonstrate that the pellet freezing method using dry ice can be used successfully for the cryopreservation of blastocysts. PMID:12148062

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

    Science.gov (United States)

    Sivakumar, S

    2015-08-01

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

  4. PEM Fuel Cell Freeze Durability and Cold Start Project

    Energy Technology Data Exchange (ETDEWEB)

    Patterson, T.; O' Neill, Jonathan

    2008-01-02

    UTC has taken advantage of the unique water management opportunities inherent in micro-porous bipolar-plates to improve the cold-start performance of its polymer electrolyte fuel cells (PEFC). Diagnostic experiments were used to determine the limiting factors in micro-porous plate PEFC freeze performance and the causes of any performance decay. Alternative cell materials were evaluated for their freeze performance. Freeze-thaw cycling was also performed to determine micro-porous plate PEFC survivability. Data from these experiments has formed the basis for continuing development of advanced materials capable of supporting DOE's cold-start and durability objectives.

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

    Science.gov (United States)

    Sheppard, S C; Stephenson, G L

    2012-01-01

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

  6. Microscale interactions between earthworms and microorganisms: a review

    Directory of Open Access Journals (Sweden)

    Zirbes, L.

    2012-01-01

    Full Text Available Microorganisms are well adapted to their soil microhabitat where they live together in consortia, interacting with other living members, including earthworms. This literature review consists of four sections that focus on microscale interactions between earthworms and microorganisms. The first part is devoted to nephridia symbiosis. Recent discoveries show that Verminephrobacter spp. is present as a symbiont in earthworm nephridia. The second section deals with earthworm food preference and focuses on the major hypotheses of foraging strategies. The third section presents evidence of gut symbionts and highlights the need for additional studies in this field. The last section of this review explains why microorganism activities are enhanced in burrows and casts of earthworms.

  7. Vulnerable Earthworm Species Identified from Nilgiri Biosphere Reserve

    Directory of Open Access Journals (Sweden)

    E.V. Ramasamy

    2011-01-01

    Full Text Available Diversity of earthworms at Nilgiri Biosphere Reserve is less known even though it is one among the biodiversity hot spots. Unless an authentic record of available earthworm species is made, the consequences of human alternation or climate change on the earthworm species diversity cannot be assessed. In this regard, the present study is relevant. Earthworms were collected from twenty three sites of NBR. The findings of this study showed that out of the total earthworm species identified from selected areas of NBR, 83.4% are native species and 16.6% are exotic. This indicates the predominance of native species in the study area possibly due to low level of disturbance in the area. Among the species identified from Mukurthi, Priodichaeta pellucida (Bourne which is listed as vulnerable and has not been encountered since its discovery about 100 years ago.

  8. Cold tolerance and freeze-induced glucose accumulation in three terrestrial slugs

    DEFF Research Database (Denmark)

    Slotsbo, Stine; Hansen, Lars Monrad; Jordaens, Kurt; Backeljau, Thierry; Malmendal, Anders; Nielsen, Niels Chr; Holmstrup, Martin

    2012-01-01

    their habitat. Slugs spontaneously froze at about -4 °C when cooled under dry conditions, but freezing of body fluids was readily induced at -1 °C when in contact with external ice crystals. All three species survived freezing for 2 days at -1 °C, and some A. rufus and A. lusitanicus also survived....... Glucose increased from about 6 to 22 µg/mg dry tissue upon freezing in A. rufus, but less so in A. ater and A. lusitanicus. Glucose may thus act as a cryoprotectant in these slugs, although the concentrations are not as high as reported for other freeze tolerant invertebrates....

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

    Science.gov (United States)

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

    2012-01-01

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

  10. Response of New zealand mudsnails Potamopyrgus antipodarum to freezing and near freezing fluctuating water temperatures

    Science.gov (United States)

    Moffitt, Christine M.; James, Christopher A.

    2012-01-01

    We explored the resilience of the invasive New Zealand mudsnail Potamopyrgus antipodarum to fluctuating winter freezing and near-freezing temperature cycles in laboratory tests. Our goal was to provide data to confirm field observations of mortality and presumed mortality in stream habitats with fluctuating freezing to near-freezing temperatures. We tested individuals from 2 locations with distinctly different thermal regimes and population densities. One location had low snail densities and water temperatures with strong diel and seasonal water variation. The other location had high snail densities and nearly constant water temperatures. Groups of individuals from both locations were tested in each of 3 laboratory-created diel thermal cycles around nominal temperatures of 0, 2, or 4C. Mortality occurred in cycles around 0C in both populations, and little to no mortality occurred at temperatures >0C. Individuals from both sources held in diel 0C cycles for 72 h showed 100% mortality. Our findings support observations from published field studies that survival was limited in infested habitats subject to freezing temperatures.

  11. Multi-element analyses of earthworms for radioecology and ecotoxicology

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, S.; Peijnenburg, W.; Muramatsu, Y. [National Institute of Radiological Sciences, Environmental and Toxicological Sciences Research Group, Inage-ku, Chiba-shi (Japan)

    2004-07-01

    Increasing concern about environmental radiation protection has raised awareness that more information is required on the transfer and accumulation of radionuclides in the biological compartments of ecosystems. ICRP (International Commission on Radiological Protection) selected earthworm as one of the reference organisms in their radiation protection recommendations. Earthworms play an important role in ecosystems, and might be a good indicator of soil contamination and its effect on the ecosystem. The elemental composition of earthworms gives useful information on background levels and possible accumulation of metals as well as related radionuclides. In addition, a change of the elemental composition itself might be a possible indicator of the effect on the earthworm and/or ecosystem. However, data for the elemental composition of earthworms are limited except for some specific heavy metals such as Cd, Zn, Pb and Cu. In this study, earthworms and their growth media were analyzed for more than 30 elements, including radionuclide related elements such as Cs, Sr, Th and U, in order to obtain the basic information on the transfer parameters of the elements. The earthworms analyzed were fed in the laboratory or collected in the environment. The concentrations and transfer factors of the elements were determined both for laboratory and natural conditions. The controlling factors on the transfer parameters such as the bioavailability of the elements in the soils will also be discussed. (author)

  12. Status, Trends, and Advances in Earthworm Research and Vermitechnology

    International Nuclear Information System (INIS)

    In this special issue reflect the developments in the fields of earthworm research and vermitechnology. Charles Darwins observation on earthworms is a milestone in understanding the soil biology and enormous contribution to some aspects of the genesis of humus and of its role in soils. Earthworms are the best known soil inhabiting animals commonly called friends of farmers due to the beneficial role they play in soil. The research on earthworms has gained importance in India as well as in other countries. In the year 1981, an international symposium entitled Earthworm Ecology: Darwin to Vermiculture was held at Cumbria, UK, to commemorate the centenary celebration of Darwins book The Formation of Vegetable Mould through the Action of Worms, with Observations on Their Habits that was published in 1881 by Murray, London, UK. In the year 2000, Vermillenium-an international workshop and symposium- was held at Kalamazoo, USA, to realize the progress achieved in this field after a decade (since 1991). Recently, Ninth International Symposium on Earthworm Ecology (ISEE-9) that was held at Xalapa, Mexico, during the 5th to 10th of September 2010 clearly proved the importance of earthworms and vermitechnology by the participation of scientists from different countries. About 300 papers were received from the researchers across the world

  13. Multi-element analyses of earthworms for radioecology and ecotoxicology

    International Nuclear Information System (INIS)

    Increasing concern about environmental radiation protection has raised awareness that more information is required on the transfer and accumulation of radionuclides in the biological compartments of ecosystems. ICRP (International Commission on Radiological Protection) selected earthworm as one of the reference organisms in their radiation protection recommendations. Earthworms play an important role in ecosystems, and might be a good indicator of soil contamination and its effect on the ecosystem. The elemental composition of earthworms gives useful information on background levels and possible accumulation of metals as well as related radionuclides. In addition, a change of the elemental composition itself might be a possible indicator of the effect on the earthworm and/or ecosystem. However, data for the elemental composition of earthworms are limited except for some specific heavy metals such as Cd, Zn, Pb and Cu. In this study, earthworms and their growth media were analyzed for more than 30 elements, including radionuclide related elements such as Cs, Sr, Th and U, in order to obtain the basic information on the transfer parameters of the elements. The earthworms analyzed were fed in the laboratory or collected in the environment. The concentrations and transfer factors of the elements were determined both for laboratory and natural conditions. The controlling factors on the transfer parameters such as the bioavailability of the elements in the soils will also be discussed. (author)

  14. The effect of anthropogenic arsenic contamination on the earthworm microbiome.

    Science.gov (United States)

    Pass, Daniel Antony; Morgan, Andrew John; Read, Daniel S; Field, Dawn; Weightman, Andrew J; Kille, Peter

    2015-06-01

    Earthworms are globally distributed and perform essential roles for soil health and microbial structure. We have investigated the effect of an anthropogenic contamination gradient on the bacterial community of the keystone ecological species Lumbricus rubellus through utilizing 16S rRNA pyrosequencing for the first time to establish the microbiome of the host and surrounding soil. The earthworm-associated microbiome differs from the surrounding environment which appears to be a result of both filtering and stimulation likely linked to the altered environment associated with the gut micro-habitat (neutral pH, anoxia and increased carbon substrates). We identified a core earthworm community comprising Proteobacteria (?50%) and Actinobacteria (?30%), with lower abundances of Bacteroidetes (?6%) and Acidobacteria (?3%). In addition to the known earthworm symbiont (Verminephrobacter sp.), we identified a potential host-associated Gammaproteobacteria species (Serratia sp.) that was absent from soil yet observed in most earthworms. Although a distinct bacterial community defines these earthworms, clear family- and species-level modification were observed along an arsenic and iron contamination gradient. Several taxa observed in uncontaminated control microbiomes are suppressed by metal/metalloid field exposure, including eradication of the hereto ubiquitously associated Verminephrobacter symbiont, which raises implications to its functional role in the earthworm microbiome. PMID:25404571

  15. Earthworm tolerance to residual agricultural pesticide contamination

    DEFF Research Database (Denmark)

    Givaudan, Nicolas; Binet, Françoise; Le Bot, Barbara; Wiegand, Claudia

    This study investigates if acclimatization to residual pesticide contamination in agricultural soils is reflected in detoxification, antioxidant enzyme activities and energy budget of earthworms. Five fields within a joint agricultural area exhibited different chemical and farming histories from...... soluble glutathione-S-transferases (sGST) and catalase increased with soil pesticide contamination in A. caliginosa. Pesticide stress was reflected in depletion of energy reserves in A. chlorotica. Acute exposure of pre-adapted and naïve A. caliginosa to pesticides (fungicide Opus ®, 0.1 μg active...

  16. Freezing increment in keratophakia.

    Science.gov (United States)

    Swinger, C A; Wisnicki, H J

    In homoplastic keratomileusis, keratophakia, and epikeratophakia, the corneal tissue that provides the final refractive lenticule undergoes a conformational change when frozen. Because corneal tissue is composed primarily of water, an assumed value of 9.08% (approximate volumic percentage expansion of water when frozen) is frequently used for the increase in thickness, or freezing increment, rather than measuring it directly. We evaluated 32 cases of clinical keratophakia and found the increase in thickness to average 37 +/- 21%. In this series of 32 cases, the percentage of patients with a greater than 4 D residual refractive error was 16%. If an assumed freezing increment of 9.08% had been used, the percentage would have been 28%, with two-thirds of these 28% manifesting a marked undercorrection. Because of a lack of studies documenting the behavior of corneal tissue following cryoprotection and freezing, it is suggested that measurements be taken during homoplastic surgery to minimize the potential for significant inaccuracy in obtaining the desired optic result. PMID:3915238

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

    Science.gov (United States)

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

    2006-07-01

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

  18. Freeze tolerance and accumulation of cryoprotectants in the enchytraeid Enchytraeus albidus (Oligochaeta) from Greenland and Europe

    DEFF Research Database (Denmark)

    Slotsbo, Stine; Maraldo, Kristine; Malmendal, Anders; Nielsen, Niels Chr; Holmstrup, Martin

    2008-01-01

    tolerant, with freeze tolerance varying extensively between Greenlandic and European populations. Two populations from sub Arctic (Nuuk) and high Arctic Greenland (Zackenberg) survived freezing at -15 degrees C, whereas only 30% of a German population survived this temperature. When frozen, E. albidus...... resonance spectrometry (NMR) was used to screen for other putative cryoprotectants. Proline, glutamine and alanine were up regulated in frozen worms at -2 degrees C but only in relatively small concentrations suggesting that they were of little significance for freeze survival. The present study confirms...

  19. Importance of freeze-thaw events in low temperature ecotoxicology of cold tolerant enchytraeids

    DEFF Research Database (Denmark)

    Patrcio Silva, Ana L; Enggrob, Kirsten; Slotsbo, Stine; Amorim, Mnica J B; Holmstrup, Martin

    2014-01-01

    Due to global warming it is predicted that freeze-thaw cycles will increase in Arctic and cold temperate regions. The effects of this variation becomes of particular ecological importance to freeze-tolerant species when it is combined with chemical pollutants. We compared the effect of control...... temperature (2 C), daily freeze-thaw cycles (2 to -4 C) and constant freezing (-2 C) temperatures on the cold-tolerance of oligochaete worms (Enchytraeus albidus) and tested how survival was influenced by pre-exposure to 4-nonylphenol (4-NP), a common nonionic detergent found in sewage sludge amended soils...... concentrations of free glucose. Further, exposure to freeze-thaw cycles resulted in higher concentrations of 4-NP in worm tissues as compared to constant freezing or control temperature (2 C). Thus, worms exposed to combined effect of freeze-thaw cycles and 4-NP suffer higher consequences, with the toxic effect...

  20. Slow desiccation improves dehydration tolerance and accumulation of compatible osmolytes in earthworm cocoons (Dendrobaena octaedra Savigny).

    Science.gov (United States)

    Petersen, Christina R; Holmstrup, Martin; Malmendal, Anders; Bayley, Mark; Overgaard, Johannes

    2008-06-01

    The earthworm, Dendrobaena octaedra, is a common species in temperate and subarctic regions of the northern hemisphere. The egg capsules ('cocoons') of D. octaedra are deposited in the upper soil layers where they may be exposed to desiccation. Many previous studies on desiccation tolerance in soil invertebrates have examined acute exposure to harsh desiccating conditions, however, these animals are often more likely to be exposed to a gradually increasing drought stress. In the present study we slowly desiccated D. octaedra cocoons to simulate ecologically realistic drought conditions and the results clearly demonstrate that gradually dehydrated cocoons show an increased tolerance of extreme drought compared with acutely dehydrated cocoons. NMR spectroscopic analysis of compatible osmolytes revealed the presence of sorbitol, glucose, betaine, alanine and mannitol in dehydrated embryos. The superior drought survival of gradually desiccated embryos could partly be attributed to a higher accumulation of osmolytes (especially sorbitol). Thus, gradually and acutely desiccated embryos accumulated approximately 2 mol l(-1) and 1 mol l(-1) total osmolytes, respectively. However, in addition to osmolyte accumulation, the gradually desiccated cocoons also tolerated a higher degree of water loss, demonstrating that gradually dehydrated D. octaedra cocoons are able to survive loss of approximately 95% of the original water content. Although D. octaedra embryos can probably not be categorized as a truly anhydrobiotic organism we propose that they belong in a transition zone between the desiccation sensitive and the truly anhydrobiotic organisms. Clearly, these earthworm embryos share many physiological traits with anhydrobiotic organisms. PMID:18515720

  1. Further contribution to knowledge of the earthworms of umadija, Serbia

    Directory of Open Access Journals (Sweden)

    Stojanovi? Mirjana M.

    2005-01-01

    Full Text Available The authors present the results of recent investigations of earthworms from umadija. Research was carried out during 1996-2003 and included natural and cultivated biotopes from various parts of umadija. We found 27 taxa including six species new for the earthworm fauna of umadija: Dendrobaena alpina, Helodrilus cernosvitovianus, Octolasion cyaneum, Octodrilus complanatus, Serbiona serbica, and Serbiona paratuleskovi. Up to 1995, the total number of earthworm taxa in umadija was 37. After our present study this number has risen to 43 taxa. As for the zoogeographical position of the earthworms of umadija, the established taxa have the following types of distribution: European (11 taxa, cosmopolitan (10, Holarctic (eight Palearctic (two, South European (five, Balkan (three and endemic (four.

  2. Identification and Classification of Earthworm Species in Guyana

    Directory of Open Access Journals (Sweden)

    Preeta Saywack

    2011-01-01

    Full Text Available Earthworms are very important organisms, they are both environmentally and economically beneficial and hence their correct identification and classification is very vital. Taxonomy aims to classify organisms based on their similarities and differences. The present study was carried out during the year 2006-2007 at University of Guyana, Georgetown focusing on identification and classification of local earthworm species of Guyana and comparison with a known non-native species (California red. The earthworms were collected (using hand sorting method, cultured and then carefully examined (worms were washed with water, preserved in 10% formalin solution. The two species studied were identified based on their external morphology and internal anatomy as well as their ecological features. The California red earthworm was grouped under the family Lumbricidae and identified as Eisenia foetida, while the local species was grouped under the family Eudrilidae and identified as Eudrilus eugenia.

  3. Menadione enhances oxyradical formation in earthworm extracts: vulnerability of earthworms to quinone toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Osman, A.M.; Besten, P.J. den; Noort, P.C.M. van

    2003-10-08

    NAD(P)H-cytochrome c reductase activities have been determined in the earthworms, L. rubellus and A. chlorotica, extracts. Menadione (0.35 mM, maximum concentration tested) was found to stimulate the rates of NADPH- and NADH-dependent cytochrome c reduction by three- and twofold, respectively. Superoxide dismutase (SOD) inhibited completely this menadione-mediated stimulation, suggesting that {center_dot}O{sub 2}{sup -} is involved in the redox cycling of menadione. However, SOD had no effect on the basal activity (activity in the absence of quinone) in the case of NADH-dependent cytochrome c reduction, whereas it partially inhibited the basal activity of NADPH-cytochrome c reduction. This indicates direct electron transfer in the former case and the formation of superoxide anion in the latter. DT-diaphorase, measured as the dicumarol-inhibitable part of menadione reductase activity, was not detectable in the earthworms' extracts. In contrast, it was found that DT-diaphorase represents about 70% of the menadione reductase activities in the freshwater mussel, Dreissena polymorpha. The results of this work suggest that earthworms, compared with mussels, could be more vulnerable to oxidative stress from quinones due to lack, or very low level of DT-diaphorase, an enzyme considered to play a significant role in the detoxification of quinones. On the contrary, mussels have efficient DT-diaphorase, which catalyzes two-electron reduction of menadione directly to hydroquinone, thus circumventing the formation of semiquinone.

  4. Menadione enhances oxyradical formation in earthworm extracts: vulnerability of earthworms to quinone toxicity

    International Nuclear Information System (INIS)

    NAD(P)H-cytochrome c reductase activities have been determined in the earthworms, L. rubellus and A. chlorotica, extracts. Menadione (0.35 mM, maximum concentration tested) was found to stimulate the rates of NADPH- and NADH-dependent cytochrome c reduction by three- and twofold, respectively. Superoxide dismutase (SOD) inhibited completely this menadione-mediated stimulation, suggesting that O2- is involved in the redox cycling of menadione. However, SOD had no effect on the basal activity (activity in the absence of quinone) in the case of NADH-dependent cytochrome c reduction, whereas it partially inhibited the basal activity of NADPH-cytochrome c reduction. This indicates direct electron transfer in the former case and the formation of superoxide anion in the latter. DT-diaphorase, measured as the dicumarol-inhibitable part of menadione reductase activity, was not detectable in the earthworms' extracts. In contrast, it was found that DT-diaphorase represents about 70% of the menadione reductase activities in the freshwater mussel, Dreissena polymorpha. The results of this work suggest that earthworms, compared with mussels, could be more vulnerable to oxidative stress from quinones due to lack, or very low level of DT-diaphorase, an enzyme considered to play a significant role in the detoxification of quinones. On the contrary, mussels have efficient DT-diaphorase, which catalyzes two-electron reduction of menadione directly to hydroquinone, thus circumventing the formation of semiquinone

  5. Root Foraging Influences Plant Growth Responses to Earthworm Foraging

    OpenAIRE

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

    2014-01-01

    Interactions among the foraging behaviours of co-occurring animal species can impact population and community dynamics; the consequences of interactions between plant and animal foraging behaviours have received less attention. In North American forests, invasions by European earthworms have led to substantial changes in plant community composition. Changes in leaf litter have been identified as a critical indirect mechanism driving earthworm impacts on plants. However, there has been limited...

  6. Transmission of Nephridial Bacteria of the Earthworm Eisenia fetida

    OpenAIRE

    Davidson, Seana K.; Stahl, David A.

    2006-01-01

    The lumbricid earthworms (annelid family Lumbricidae) harbor gram-negative bacteria in their excretory organs, the nephridia. Comparative 16S rRNA gene sequencing of bacteria associated with the nephridia of several earthworm species has shown that each species of worm harbors a distinct bacterial species and that the bacteria from different species form a monophyletic cluster within the genus Acidovorax, suggesting that there is a specific association resulting from radiation from a common b...

  7. Earthworm (Eisenia andrei Avoidance of Soils Treated with Cypermethrin

    Directory of Open Access Journals (Sweden)

    Mara M. de Andra

    2011-11-01

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

  8. Earthworms as colonizers of natural and cultivated soil environments

    OpenAIRE

    H. J.P. Eijsackers

    2011-01-01

    For cultivated soils, the important function of earthworms as ecosystem engineers and their major contribution to the composition and functioning of soil ecosystems with a varying species diversity has been extensively addressed. However, the role of earthworms as colonizers of virgin, uncultivated soil in the process of soil formation has been little researched and long underrated. To better understand this role, the following questions need to be considered: (1) what makes an early colonize...

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

    Science.gov (United States)

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

    2013-04-01

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

  10. Bacteria and protozoa in soil microhabitats as affected by earthworms

    DEFF Research Database (Denmark)

    Winding, Anne; Rnn, Regin; Hendriksen, Niels B.

    1997-01-01

    The effects of incorporation of elm leaves (Ulmus glabra) into an agricultural sandy loam soil by earthworms (Lumbricus festivus) on the bacterial and protozoan populations were investigated. Three model systems consisting of soil, soil with leaves, and soil with leaves and earthworms, respectively, were compared. The total, viable, and culturable number of bacteria, the metabolic potentials of bacterial populations, and the number of protozoa and nematodes were determined in soil size fractions...

  11. Greenhouse-gas emissions from soils increased by earthworms

    OpenAIRE

    Lubbers, I.M.; Groenigen, K.J., van; Fonte, S.J.; Six, J.; Brussaard, L.; van Groenigen, J. W.

    2013-01-01

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

  12. Earthworms lost from pesticides application in potato crops

    Science.gov (United States)

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

    2010-05-01

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

  13. Freezing in random graph ferromagnets

    OpenAIRE

    Svenson, Pontus

    2001-01-01

    Using T=0 Monte Carlo and simulated annealing simulation, we study the energy relaxation of ferromagnetic Ising and Potts models on random graphs. In addition to the expected exponential decay to a zero energy ground state, a range of connectivities for which there is power law relaxation and freezing to a metastable state is found. For some connectivities this freezing persists even using simulated annealing to find the ground state. The freezing is caused by dynamic frustr...

  14. Freezing parameters of soft spheres

    OpenAIRE

    Wilding, Nigel

    2009-01-01

    Abstract The phase switch Monte Carlo method is employed to determine the freezing properties of particles interacting via an r-12 repulsive potential. We establish that at the equilibrium freezing point the face centred cubic (fcc) structure has a free energy that is lower than that of the metastable body centred cubic (bcc) structure by 0.0184(4) kBT per particle. Thus the bcc structure is not the stable solid phase at freezing despite being commonly observed in...

  15. Multi-element analyses of earthworms for radioecology

    International Nuclear Information System (INIS)

    Increasing attention on the environmental radiation protection realizes that more information is required on the transfer and accumulation of radionuclides in the biological compartments of the ecosystems. Earthworms play an important role in ecosystems, and might be a good indicator of soil contamination and its effect on the ecosystem. The elemental composition of earthworms gives useful information on background levels and possible accumulation of metals as well as related radionuclides. However, data for the elemental composition of earthworms are limited except for some specific heavy metals such as Cd, Zn, Pb and Cu. In this study, earthworms and their growth media were analyzed for 35 elements, including radionuclide related elements such as Cs, Sr, Th and U, in order to obtain the basic information on the transfer parameters of the elements. The earthworms analyzed were fed in the laboratory or collected in the environment. The concentrations and transfer factors (TFs) of the elements were determined both for laboratory and natural conditions. Relatively high TFs were observed for Na, Mg, P, K, Ca, Co, Ni, Cu, Zn, As, Se, Rb, Mo and Cd. The TFs for Al, Sc, Ti, Y, Nb and lanthanide elements were low. The TFs of Cs were different depending on the medium (soil type), indicating that bioavailability of Cs in the medium might be one of the important controlling factors of Cs concentration in earthworm. (author)

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

    Science.gov (United States)

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

    2015-01-01

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

  17. Freezing in random graph ferromagnets

    CERN Document Server

    Svenson, P

    2002-01-01

    Using T=0 Monte Carlo and simulated annealing simulation, we study the energy relaxation of ferromagnetic Ising and Potts models on random graphs. In addition to the expected exponential decay to a zero energy ground state, a range of connectivities for which there is power law relaxation and freezing to a metastable state is found. For some connectivities this freezing persists even using simulated annealing to find the ground state. The freezing is caused by dynamic frustration in the graphs, and is a feature of the local search-nature of the Monte Carlo dynamics used. The implications of the freezing on agent-based complex systems models are briefly considered.

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

    Science.gov (United States)

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

    2014-03-01

    The upper limit concentrations of metals established by international legislations for dredged sediment disposal and soil quality do not take into consideration the properties of tropical soils (generally submitted to more intense weathering processes) on metal availability and ecotoxicity. Aiming to perform an evaluation on the suitability of these threshold values in tropical regions, the ecotoxicity of metal-contaminated dredged sediment from the Guanabara Bay (Rio de Janeiro, Brazil) was investigated. Acute and avoidance tests with Eisenia andrei were performed with mixtures of dredged sediment with a ferralsol (0.00, 6.66, 13.12, 19.98, and 33.30 %) and a chernosol (0.00, 6.58, 13.16, 19.74, and 32.90 %). Mercury, lead, nickel, chromium, copper, and zinc concentrations were measured in test mixtures and in tissues of surviving earthworms from the acute tests. While ferralsol test mixtures provoked significant earthworm avoidance response at concentrations ?13.31 %, the chernosol mixtures showed significant avoidance behavior only at the 19.74 % concentration. The acute tests showed higher toxicity in ferralsol mixtures (LC50?=?9.9 %) compared to chernosol mixtures (LC50?=?16.5 %), and biomass increased at the lowest sediment doses in treatments of both test soils. Most probably, the expansive clay minerals present in chernosol contributed to reduce metal availability in chernosol mixtures, and consequently, the ecotoxicity of these treatments. The bioconcentration factors (BCF) for zinc and copper were lower with increasing concentrations of the dredged sediment, indicating the existence of internal regulating processes. Although the BCF for mercury also decreased with the increasing test concentrations, the known no biological function of this metal in the earthworms metabolism lead to suppose that Hg measured was not present in bioaccumulable forms. BCFs estimated for the other metals were generally higher in the highest dredged sediment doses. PMID:24122142

  19. Heavy metal induced biomolecule and genotoxic changes in earthworm Eisenia fetida

    Directory of Open Access Journals (Sweden)

    G. Muthukaruppan

    2015-09-01

    Full Text Available A vibrational [Fourier transform infrared (FTIR] spectroscopic method was used for the structural and compositional analysis of earthworm Eisenia fetida by monitoring of metal binding and further transformations in live cells. The FTIR analyses for metals taken up by the E. fetida will be useful for analyzing the impact of the heavy metal stress on the worm metabolism. The epigeic earthworm E. fetida were exposed to 100 %, 75 %, 50 %, 30 %, 25 %, 15 % and 5 % of dried automobile service station waste mud. All the earthworms exposed in the 100 %, 75 % and 50 % concentrations didnt survived within 10days. Further experiments were conducted with 25 %, 15 % and 5 % concentration of wastes. Each concentration level was tested with three replicates using 10 animals and the metabolic response after exposure to the heavy metal containing service station waste mud was assessed by FTIR. Furthermore we also emphasized that DNA damage was confirmed with the use of other biomarker like comet assay. The peaks at 1045, 1080, 1236 cm?1 and 1650 cm?1 represented the overall susceptibility of nucleotides, phospholipids, DNA and RNA. Nucleic acids and proteins were modified due to heavy metal accumulation. In flow-through, single cell gel electrophoresis revealed the degradation nuclear DNA. Heavy metals accumulation in the worms was measured and it was found that lead, zinc and copper accumulation increased in the treatment group. Without the use of biomarkers for identifying ecological risks of land contamination, traditional assessment would be difficult to interpret. This new FTIR based biomolecules study revealed a clear molecule shift in the exposed worms, due to heavy metal accumulation.

  20. Importance of freeze-thaw events in low temperature ecotoxicology of cold tolerant enchytraeids

    DEFF Research Database (Denmark)

    Patrcio Silva, Ana L; Enggrob, Kirsten

    2014-01-01

    Due to global warming it is predicted that freeze-thaw cycles will increase in Arctic and cold temperate regions. The effects of this variation becomes of particular ecological importance to freeze-tolerant species when it is combined with chemical pollutants. We compared the effect of control temperature (2 C), daily freeze-thaw cycles (2 to -4 C) and constant freezing (-2 C) temperatures on the cold-tolerance of oligochaete worms (Enchytraeus albidus) and tested how survival was influenced by pre-exposure to 4-nonylphenol (4-NP), a common nonionic detergent found in sewage sludge amended soils. Results showed that combined effect of 4-NP and daily freeze-thaw cycles can cause higher mortality to worms as compared with sustained freezing or control temperature. Exposure to 4-NP caused a substantial depletion of glycogen reserves which is catabolized during freezing to produce cryoprotective concentrations of free glucose. Further, exposure to freeze-thaw cycles resulted in higher concentrations of 4-NP inworm tissues as compared to constant freezing or control temperature (2 C). Thus, worms exposed to combined effect of freeze-thaw cycles and 4-NP suffer higher consequences, with the toxic effect of the chemical potentiating the deleterious effects of freezing and thawing.

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

    Energy Technology Data Exchange (ETDEWEB)

    Vliet, P.C.J. van [Wageningen University, Department of Soil Quality, P.O. Box 8005, 6700 EC Wageningen (Netherlands)]. E-mail: petra.vanvliet@wur.nl; Zee, S.E.A.T.M. van der [Wageningen University, Department of Soil Quality, P.O. Box 8005, 6700 EC Wageningen (Netherlands); Ma, W.C. [Alterra, P.O. Box 47, 6700 AA Wageningen (Netherlands)

    2005-12-15

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

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

    International Nuclear Information System (INIS)

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

  3. STUDIES ON BIOREMEDIATION OF PHENOL BY EARTHWORM

    Directory of Open Access Journals (Sweden)

    Akhilesh Verma

    2015-10-01

    Full Text Available Three species of earthworms namely Eiseniafoetida, Eudrilluseu geniaand Anantapurspecies were procured from different institutions. They were tested for their tolerance to phenol and bioremediation activity. The bioremediation assays were performed in soil with phenol dispersed in water. Different concentrations of phenol samples ranging from 20 to 100ppm were taken for experimentation. The remediation process of initial phenol concentration was investigated. The results indicated that Eiseniafoetida and Eudrilluseugenia were the best tolerant species, while the Anantapur species was found to be least tolerant. As the initial concentration of phenol increased, there was an increase in the percentage of bioremediation with respect to Eiseniafoetida.But with species Eudrilluseugenia and Anantapur species, the percentage of uptake of phenol at 24 hours decreased with increase in initial phenol concentration. This indicates that the species Eiseniafoetida is most tolerant species since it is able to uptake 100ppm phenol completely with in 72hours.

  4. Performance Characteristics of an Isothermal Freeze Valve

    Energy Technology Data Exchange (ETDEWEB)

    Hailey, A.E.

    2001-08-22

    This document discusses performance characteristics of an isothermal freeze valve. A freeze valve has been specified for draining the DWPF melter at the end of its lifetime. Two freeze valve designs have been evaluated on the Small Cylindrical Melter-2 (SCM-2). In order to size the DWPF freeze valve, the basic principles governing freeze valve behavior need to be identified and understood.

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

    Energy Technology Data Exchange (ETDEWEB)

    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

    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.

  6. Heat shock protects germinating conidiospores of Neurospora crassa against freezing injury.

    OpenAIRE

    Guy, C L; Plesofsky-Vig, N; Brambl, R

    1986-01-01

    Germinating conidiospores of Neurospora crassa that were exposed to 45 degrees C, a temperature that induces a heat shock response, were protected from injury caused by freezing in liquid nitrogen and subsequent thawing at 0 degrees C. Whereas up to 90% of the control spores were killed by this freezing and slow thawing, a prior heat shock increased cell survival four- to fivefold. Survival was determined by three assays: the extent of spore germination in liquid medium, the number of colonie...

  7. Earthworm Population Density in Sugarcane Cropping System Applied with Various Quality of Organic Matter

    OpenAIRE

    Nurhidayati Nurhidayati; Endang Arisoesilaningsih; Didik Suprayogo; Kurniatun Hairiah

    2012-01-01

    Earthworms population in the soil are greatly impacted by agricultural management, yet little is known about how the quality and quantity of organic matter addition interact in sugarcane cropping system to earthworm population. This study describes the effect of various organic matter and application rates on earthworms in sugarcane cropping system. Earthworms were collected in April, July and December from 48 experimental plots under five kinds of organic matter application : (1) cattle manu...

  8. Earthworms and collembola relationships: effects of predatory centipedes and humus forms

    OpenAIRE

    Salmon, Sandrine; Geoffroy, Jean-Jacques; Ponge, Jean-Franois

    2005-01-01

    Relationships between anecic earthworms (Lumbricus terrestris and Aporrectodea giardi) and the collembolan species Heteromurus nitidus (Templeton, 1835), which is known to be attracted to earthworms, were investigated in an 8-week laboratory experiment. Our aims were (1) to assess whether earthworms influence the population dynamics of H. nitidus, and (2) to study pathways of influence and how earthworm effects are modified by humus forms and predators. Using microcosms with three defaunated ...

  9. Engineering of Soil Biological Quality from Nickel Mining Stockpile Using Two Earthworm Ecological Groups

    OpenAIRE

    L M H Kilowasid; H Herlina; H Syaf; L Safuan; M. Tufaila; S Leomo; B Widiawan

    2015-01-01

    Earthworms have the ability in modifying soil biological quality for plant growth. Their ability is mostly depending on its ecological groups. The objectives of the research were to study the influence of two ecological groups of earthworms on soil microbial activity and soil micro-fauna abundance, and to know the potential of soil modified by earthworms as plant growth medium. Eight combination of individual earthworm from epigeic and endogeic groups was applied into pot that was filled by ...

  10. Beneficial Effect of Verminephrobacter Nephridial Symbionts on the Fitness of the Earthworm Aporrectodea tuberculata?

    OpenAIRE

    Lund, Marie B.; Holmstrup, Martin; Lomstein, Bente A.; Damgaard, Christian; Schramm, Andreas

    2010-01-01

    Almost all lumbricid earthworms (Oligochaeta: Lumbricidae) harbor species-specific Verminephrobacter (Betaproteobacteria) symbionts in their nephridia (excretory organs). The function of the symbiosis, and whether the symbionts have a beneficial effect on their earthworm host, is unknown; however, the symbionts have been hypothesized to enhance nitrogen retention in earthworms. The effect of Verminephrobacter on the life history traits of the earthworm Aporrectodea tuberculata (Eisen) was inv...

  11. Do earthworms impact metal mobility and availability in soil? A review

    OpenAIRE

    Sizmur, T; Hodson, M. E.

    2009-01-01

    The importance of earthworms to ecosystem functioning has led to many studies on the impacts of metals on earthworms. Far less attention has been paid to the impact that earthworms have on soil metals both in terms of metal mobility and availability. In this review we consider which earthworms have been used in such studies, which soil components have been investigated, which types of soil have been used and what measures of mobility and availability applied. We proceed to review proposed rea...

  12. Freeze-drying wet digital prints: An option for salvage?

    International Nuclear Information System (INIS)

    On the occasion of the collapse of the Historical Archive of the City of Cologne in March 2009 and the ensuing salvage effort, questions were raised about the use of freeze-drying for soaked digital prints, a technique that has not yet been evaluated for these materials. This study examines the effects of immersion, air-drying, drying in a blotter stack, freezing and freeze-drying on 35 samples of major digital printing processes. The samples were examined visually before, during and after testing; evaluation of the results was qualitative. Results show that some prints were already damaged by immersion alone (e.g. bleeding inks and soluble coatings) to the extent that the subsequent choice of drying method made no significant difference any more. For those samples that did survive immersion, air-drying proved to be crucial for water-sensitive prints, since any contact with the wet surface caused serious damage. Less water-sensitive prints showed no damage throughout the entire procedure, regardless of drying method. Some prints on coated media suffered from minor surface disruption up to total delamination of the surface coating due to the formation of ice crystals during shock-freezing. With few exceptions, freeze-drying did not cause additional damage to any of the prints that hadn't already been damaged by freezing. It became clear that an understanding of the process and materials is important for choosing an appropriate drying method.

  13. Understanding Slag Freeze Linings

    Science.gov (United States)

    Fallah-Mehrjardi, Ata; Hayes, Peter C.; Jak, Evgueni

    2014-09-01

    Slag freeze linings, the formation of protective deposit layers on the inner walls of furnaces and reactors, are increasingly used in industrial pyrometallurgical processes to ensure that furnace integrity is maintained in these aggressive, high-temperature environments. Most previous studies of freeze-linings have analyzed the formation of slag deposits based solely on heat transfer considerations. These thermal models have assumed that the interface between the stationary frozen layer and the agitated molten bath at steady-state deposit thickness consists of the primary phase, which stays in contact with the bulk liquid at the liquidus temperature. Recent experimental studies, however, have clearly demonstrated that the temperature of the deposit/liquid bath interface can be lower than the liquidus temperature of the bulk liquid. A conceptual framework has been proposed to explain the observations and the factors influencing the microstructure and the temperature of the interface at steady-state conditions. The observations are consistent with a dynamic steady state that is a balance between (I) the rate of nucleation and growth of solids on detached crystals in a subliquidus layer as this fluid material moves toward the stagnant deposit interface and (II) the dissolution of these detached crystals as they are transported away from the interface by turbulent eddies. It is argued that the assumption that the interface temperature is the liquidus of the bulk material represents only a limiting condition, and that the interface temperature can be between T liquidus and T solidus depending on the process conditions and bath chemistry. These findings have implications for the modeling approach and boundary conditions required to accurately describe these systems. They also indicate the opportunity to integrate considerations of heat and mass flows with the selection of melt chemistries in the design of future high temperature industrial reactors.

  14. Generalized structural theory of freezing

    International Nuclear Information System (INIS)

    The first-principles order parameter theory of freezing, proposed in an earlier work, has been successful in yielding quantitative agreement with known freezing parameters for monoatomic liquids forming solids with one atom per unit cell. A generalization of this theory is presented here to include the effects of a basis set of many atoms per unit cell. The basic equations get modified by the 'density structure factors' fsub(i) which arise from the density variations within the unit cell. Calculations are presented for the important case of monoatomic liquids freezing into hexagonal close packed solids. It is concluded that all freezing transitions can be described by using structural correlations in the liquid instead of the pair potential; and that the three body correlations are important in deciding the type of solid formed after freezing. (author)

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

    Science.gov (United States)

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

    2009-01-01

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

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

    Science.gov (United States)

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-09-01

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

  18. Establishing principal soil quality parameters influencing earthworms in urban soils using bioassays

    Energy Technology Data Exchange (ETDEWEB)

    Hankard, Peter K. [Centre for Ecology and Hydrology, Monks Wood, Abbots Ripton, Huntingdon PE28 2LS (United Kingdom)]. E-mail: pkh@ceh.ac.uk; Bundy, Jacob G. [University of Cambridge, Department of Biochemistry, 80 Tennis Court Road, Cambridge CB2 1GA (United Kingdom); Spurgeon, David J. [Centre for Ecology and Hydrology, Monks Wood, Abbots Ripton, Huntingdon PE28 2LS (United Kingdom); Weeks, Jason M. [WRc-NSF Ltd, Henley Road, Medmenham, Marlow, Buckinghamshire SL7 2HD (United Kingdom); Wright, Julian [Centre for Ecology and Hydrology, Monks Wood, Abbots Ripton, Huntingdon PE28 2LS (United Kingdom); Weinberg, Claire [Centre for Ecology and Hydrology, Monks Wood, Abbots Ripton, Huntingdon PE28 2LS (United Kingdom); Svendsen, Claus [Centre for Ecology and Hydrology, Monks Wood, Abbots Ripton, Huntingdon PE28 2LS (United Kingdom)

    2005-01-01

    Potential contamination at ex-industrial sites means that, prior to change of use, it will be necessary to quantify the extent of risks to potential receptors. To assess ecological hazards, it is often suggested to use biological assessment to augment chemical analyses. Here we investigate the potential of a commonly recommended bioassay, the earthworm reproduction test, to assess the status of urban contaminated soils. Sample points at all study sites had contaminant concentrations above the Dutch soil criteria Target Values. In some cases, the relevant Intervention Values were exceeded. Earthworm survival at most points was high, but reproduction differed significantly in soil from separate patches on the same site. When the interrelationships between soil parameters and reproduction were studied, it was not possible to create a good model of site soil toxicity based on single or even multiple chemical measurements of the soils. We thus conclude that chemical analysis alone is not sufficient to characterize soil quality and confirms the value of biological assays for risk assessment of potentially contaminated soils. - Bioassays must be applied for the risk assessment complexly-polluted sites to complement chemical analysis of soils.

  19. Metallothionein response in earthworms Lampito mauritii (Kinberg) exposed to fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Maity, S.; Hattacharya, S.; Chaudhury, S. [Visva Bharati, Santini Ketan (India)

    2009-10-15

    Among pollutants, the coal fly ash occupies a significant position in industrial wastes. The fly ash matrix is a complex mixture of various organic (polyhalogenated compounds) and inorganic (Si, Al, Fe, As, Cd, Bi, Hg, etc.) chemicals. The application of fly ash for agricultural purposes and as landfills may lead to the contamination of the land with some of the toxic chemical compounds present in fly ash. Thus prior to the application of fly ash for developmental activities, it requires bio-monitoring and risk characterization. In order to achieve this objective adult Lampito mauritii were exposed to different proportions of fly ash in soil for 30 d and the concentrations of metallothionein in earthworm were assessed. The results revealed that up to 50% of fly ash amendment does not apparently harm the earthworm in respect of their survival and growth. A significant increase in tissue metallothionein level was recorded in L mauritii exposed to fly ash amended soil without tissue metal accumulation indicating that metallothionein is involved in scavenging of free radicals and reactive oxygen species metabolites. It is concluded that this biochemical response observed in L mauritii exposed to fly ash amended soil could be used in ecotoxicological field monitoring.

  20. Establishing principal soil quality parameters influencing earthworms in urban soils using bioassays

    International Nuclear Information System (INIS)

    Potential contamination at ex-industrial sites means that, prior to change of use, it will be necessary to quantify the extent of risks to potential receptors. To assess ecological hazards, it is often suggested to use biological assessment to augment chemical analyses. Here we investigate the potential of a commonly recommended bioassay, the earthworm reproduction test, to assess the status of urban contaminated soils. Sample points at all study sites had contaminant concentrations above the Dutch soil criteria Target Values. In some cases, the relevant Intervention Values were exceeded. Earthworm survival at most points was high, but reproduction differed significantly in soil from separate patches on the same site. When the interrelationships between soil parameters and reproduction were studied, it was not possible to create a good model of site soil toxicity based on single or even multiple chemical measurements of the soils. We thus conclude that chemical analysis alone is not sufficient to characterize soil quality and confirms the value of biological assays for risk assessment of potentially contaminated soils. - Bioassays must be applied for the risk assessment complexly-polluted sites to complement chemical analysis of soils

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

    Science.gov (United States)

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

    2011-12-01

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

  2. Anhydrobiosis and Freezing-Tolerance : Adaptations That Facilitate the Establishment of Panagrolaimus Nematodes in Polar Habitats

    DEFF Research Database (Denmark)

    McGill, Lorraine; Shannon, Adam

    2015-01-01

    Anhydrobiotic animals can survive the loss of both free and bound water from their cells. While in this state they are also resistant to freezing. This physiology adapts anhydrobiotes to harsh environments and it aids their dispersal. Panagrolaimus davidi, a bacterial feeding anhydrobiotic nematode isolated from Ross Island Antarctica, can survive intracellular ice formation when fully hydrated. A capacity to survive freezing while fully hydrated has also been observed in some other Antarctic nematodes. We experimentally determined the anhydrobiotic and freezing-tolerance phenotypes of 24 Panagrolaimus strains from tropical, temperate, continental and polar habitats and we analysed their phylogenetic relationships. We found that several other Panagrolaimus isolates can also survive freezing when fully hydrated and that tissue extracts from these freezing-tolerant nematodes can inhibit the growth of ice crystals. We show that P. davidi belongs to a clade of anhydrobiotic and freezing-tolerant panagrolaimids containing strains from temperate and continental regions and that P. superbus, an early colonizer at Surtsey island, Iceland after its volcanic formation, is closely related to a species from Pennsylvania, USA. Ancestral state reconstructions show that anhydrobiosis evolved deep in the phylogeny of Panagrolaimus. The early-diverging Panagrolaimus lineages are strongly anhydrobiotic but weakly freezing-tolerant, suggesting that freezing tolerance is most likely a derived trait. The common ancestors of the davidi and the superbus clades were anhydrobiotic and also possessed robust freezing tolerance, along with a capacity to inhibit the growth and recrystallization of ice crystals. Unlike other endemic Antarctic nematodes, the life history traits of P. davidi do not show evidence of an evolved response to polar conditions. Thus we suggest that the colonization of Antarctica by P. davidi and of Surtsey by P. superbus may be examples of recent ecological fitting of freezing-tolerant anhydrobiotic propagules to the respective abiotic conditions in Ross Island and Surtsey

  3. The burrowing characteristics of three common earthworm species

    International Nuclear Information System (INIS)

    The burrowing characteristics of 3 common earthworm species were studied using X-ray computed tomography (CT) scanning in large cylinders (24.1 cm diameter) packed with topsoil (0-25 cm) and subsoil (25-50 cm) to representative field bulk density values and sown with ryegrass. Replicated cylinders (n 3), kept under constant moisture and temperature conditions, were inoculated with mature species of Lumbricus rubellus, Aporrectodea caliginosa, or Octolasion cyaneum earthworms at rates similar to their population density in the field. A non-inoculated, unreplicated control was also included. The number, biomass, and activity of the 3 species were then examined. X-ray CT scanning of large-diameter soil cylinders offers an alternative method for obtaining information on the burrowing characteristics of earthworms (Jegou et al. 1999). As this method is non-destructive, repeat measurements can be made and the use of large cylinders minimises edge effects. The objectives of this study were to: (i) assess the burrowing characteristics of 3 earthworm species (under artificial conditions) through measurement of 2-D porosity using X-ray CT scanning, (ii) estimate the extent of burrow backfilling between sequential scans, and (iii) estimate the continuity of earthworm burrows with depth through hydraulic conductivity measurements. Copyright (2001) CSIRO Publishing

  4. Effectivity of the Earthworms Pheretima hupiensis, Eudrellus sp. and Lumbricus sp. on the Organic Matter Decomposition Process

    OpenAIRE

    Ea Kosman Anwar

    2009-01-01

    The earthworms are the one of soil fauna component in soil ecosystem have an important role in organic matter decomposition procces. The earthworm feed plant leaf and plant matter up to apart and dissolved. Earthworm metabolisms produce like faeces that mixed with decomposed organic matter mean vermicompost. The vermicompost fertility varies because of some kind of earthworm differ in niche and attitude. The experiment was to study the effectivity of earthworm on organic matter d...

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

    Science.gov (United States)

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

    2012-01-17

    The earthworm Eisenia fetida is one of the most used species in standardized soil ecotoxicity tests. End points such as survival, growth, and reproduction are eco-toxicologically relevant but provide little mechanistic insight into toxicity pathways, especially at the molecular level. Here we apply a toxicogenomic approach to investigate the mode of action underlying the reversible neurotoxicity of hexanitrohexaazaisowurtzitane (CL-20), a cyclic nitroamine explosives compound. We developed an E. fetida-specific shotgun microarray targeting 15119 unique E. fetida transcripts. Using this array we profiled gene expression in E. fetida in response to exposure to CL-20. Eighteen earthworms were exposed for 6 days to 0.2 μg/cm(2) of CL-20 on filter paper, half of which were allowed to recover in a clean environment for 7 days. Nine vehicle control earthworms were sacrificed at days 6 and 13, separately. Electrophysiological measurements indicated that the conduction velocity of earthworm medial giant nerve fiber decreased significantly after 6-day exposure to CL-20, but was restored after 7 days of recovery. Total RNA was isolated from the four treatment groups including 6-day control, 6-day exposed, 13-day control, and 13-day exposed (i.e., 6-day exposure followed by 7-day recovery), and was hybridized to the 15K shotgun oligo array. Statistical and bioinformatic analyses suggest that CL-20 initiated neurotoxicity by noncompetitively blocking the ligand-gated GABA(A) receptor ion channel, leading to altered expression of genes involved in GABAergic, cholinergic, and Agrin-MuSK pathways. In the recovery phase, expression of affected genes returned to normality, possibly as a result of autophagy and CL-20 dissociation/metabolism. This study provides significant insights into potential mechanisms of CL-20-induced neurotoxicity and the recovery of earthworms from transient neurotoxicity stress. PMID:22191394

  6. Freeze. How you can help prevent nuclear war

    International Nuclear Information System (INIS)

    In their book the Senators Kennedy and Hatfield prove that the United States will not be able to survive a nuclear war. The report on the freeze movement is followed by a chapter on the history of the efforts for disarmament which had been abruptly ended by President Reagan's call for the enhanced modernization of nuclear arms. But ''we have reached the unique moment in the history of the atomic age where it is possible and where it must be tried to freeze nuclear armament'', as Kennedy and Hatfield write, for ''the present nuclear balance is relatively stable''. Only by freezing the standard of armament can this balance which decides on worldwide peace be granted. (orig.)

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

    Science.gov (United States)

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

    1982-01-01

    Metal concentrations in soil may be elevated considerably when metal-laden sewage sludge is spread on land. Metals in earthworms (Lumbricidae) from agricultural fields amended with sewage sludge and from experimental plots were examined to determine if earthworms are important in transferring metals in soil to wildlife. Earthworms from four sites amended with sludge contained significantly (P . 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 metals studied. High Zn concentrations in soil substantially reduced Cd concentrations in earthworms.

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

    Science.gov (United States)

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

    2014-08-01

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

  9. Interactions of intracellular calcium and immune response in earthworms

    Directory of Open Access Journals (Sweden)

    P Engelmann

    2011-05-01

    Full Text Available Intracellular calcium level has a definite role in innate and adaptive immune signaling but its evolutionary aspects are not entirely clear yet. Very few information are accessible about calcium contents of invertebrate immunocytes, especially of celomocytes, the effector cells of earthworm immunity. Different basal and induced Ca2+ levels characterize the various celomocyte subgroups. Intracellular calcium is mostly located in the endoplasmic reticulum and celomocytes exert intracellular Ca2+ ATPase activity to maintain their calcium homeostasis. Immune molecules such as phytohemagglutinin and the chemoattractant fMLP caused the elevation of intracellular Ca2+ level in celomocytes. All the evidence suggests that Ca2+ influx may play a crucial role in the signal transduction of the earthworms innate immunity.

  10. Second contribution to the knowledge of earthworms (Lumbricidae in Montenegro

    Directory of Open Access Journals (Sweden)

    Stojanovi? Mirjana M.

    2003-01-01

    Full Text Available This paper contains the results of qualitative analysis of Lumbricidae (Oligochaeta in Montenegro, during the period 1997-2003. The research has included natural and cultivated biotopes. The presence of 15 species was established and the habitats, localities and their zoogeographical position are given. In Montenegro we found four species for the first time Dendrobaena jastrebensis, D. vejdovskyi, Octodrilus bretcheri and Lumbricus terrestris. The complete list of earthworm species in Montenegro includes 45 taxa. With respects to the zoogeographic situation of the earthworms in Montenegro, the largest number belongs to endemic (10 and European (10 species. But 8 taxa are south-European, 9 Holarctic, 7 cosmopolitan, and 1 Palearctic. The degree of endemism of the earthworm fauna of Montenegro is quite high, exceeding 22.2%.

  11. Comparative Genomics of Symbiotic Bacteria in Earthworm Nephridia

    DEFF Research Database (Denmark)

    Kjeldsen, Kasper Urup; Pinel, Nicolas; Lund, Marie Braad; Davidson, Seana; Stolyar, Sergei; Walcott, Ron; Parales, Rebecca; Richardson, P.; Stahl, David; Schramm, Andreas

    The excretory and osmoregulatory organs (nephridia) of lumbricid earthworms are densely colonized by extracellular bacterial symbionts belonging to the newly established betaproteobacterial genus Verminephrobacter. The nephridial symbiont of the earthworm Eisenia fetida was subjected to full genome...... sequencing along with two of its closest relatives; the plant pathogenic Acidovorax avena subsp. citrulli and the free-living Acidovorax sp. JS42. In addition, the genome of the nephridial symbiont of the earthworm Aporrectodea tuberculata was partially sequenced. In order to resolve the functional and...... evolutionary basis of the symbiosis we annotated and compared the genomes. The genomes ranged in size from 4.4 to 5.6 Mbp, the E. fetida symbiont genome being the largest. The symbiont genomes showed no evidence of gene-loss related to any particular type of functional gene category. In contrast, genes...

  12. Freeze concentration of dairy products

    Energy Technology Data Exchange (ETDEWEB)

    Amarnath, K.R. [Electric Power Research Inst., Palo Alto, CA (United States). Systems and Materials Dept.; Swinkels, W. [Holland Energy Technology BV (Netherlands)

    1992-12-31

    Freeze concentration as a separation process was discussed. It separates mixed liquids by converting one or more of them to a solid. The process is more energy efficient in many applications than either evaporation or distillation, the most common industrial separation methods today. An EPRI report has shown that annual heat energy consumption would decrease an estimated 1.4 quads if industry replaced evaporation and distillation in every feasible case where freezing can be used. The freeze concentration process was employed to replace thermal evaporation in the dairy industry. The goals of the project were to save energy by converting concentration processes to an efficient electrically powered refrigeration system, and to create higher quality dairy products. Tests showed equal or superior quality from freeze concentrates. 2 tabs.

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

    Energy Technology Data Exchange (ETDEWEB)

    Linder, G.; Wilbom, D. [HeronWorks Farm, Brooks, OR (United States)

    1995-12-31

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

  14. TOXICOLOGICAL EFFECTS OF ENGINEERED NANOPARTICLES ON EARTHWORMS (LUMBRICUS RUBELLUS IN SHORT EXPOSURE

    Directory of Open Access Journals (Sweden)

    Livia Vittori Antisari

    2012-07-01

    Full Text Available Nanoparticles (NPs types diffused into the environment are increasing, giving potential damages to terrestrial ecosystems. In this work we investigated the nanoparticles toxicity as pure metal and two oxides (Co, SnO2 and CeO2 on earthworm survival (Lumbricus rubellus. A concentration of 5000 mg kg-1 dry soil of each NP was compared to the chronic dose of 10 mg kg-1. The interaction between NPs and soil microbial biomass was also studied in 7 days length incubation. No mortality was observed at the end of the experiment, but high concentration of Co was found in the 5000 kg-1 dry soil treated. Despite low solubility of all NPs (solid-liquid partition coefficient > 2.8 log l kg-1 pure metal NPs were (Co more soluble than the metal oxides nanoparticles (SnO2 and CeO2.

  15. Comparative toxicity of chemicals to earthworms

    Energy Technology Data Exchange (ETDEWEB)

    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

    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.

  16. Accumulation of chlorinated benzenes in earthworms

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-12-31

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

  17. Freezing of a Liquid Marble

    OpenAIRE

    Hashmi, Ali; Strauss, Adam; Xu, Jie

    2012-01-01

    In this study, we present for the first time the observations of a freezing liquid marble. In the experiment, liquid marbles are gently placed on the cold side of a Thermo-Electric Cooler (TEC) and the morphological changes are recorded and characterized thereafter. These liquid marbles are noticed to undergo a shape transition from a spherical to a flying-saucer shaped morphology. The freezing dynamics of liquid marbles is observed to be very different from that of a freezi...

  18. FREEZE DRYING PROCESS: A REVIEW

    OpenAIRE

    Soham Shukla

    2011-01-01

    Among the various methods of drying, this article has mentioned only one most important method, Freeze drying. This method is mainly used for the drying of thermo labile materials. This method works on the principle of sublimation. This method is divided into 3 steps for its better understanding; these are Freezing, Primary drying, and secondary drying. There are many advantages and disadvantages of this method, but still this is the most useful drying method nowadays.

  19. Freeze concentration of fruit juices.

    Science.gov (United States)

    Deshpande, S S; Cheryan, M; Sathe, S K; Salunkhe, D K

    1984-01-01

    Concentration of aqueous foods such as fruit juices, milk, beer, wine, coffee, and tea, is a major unit operation in the food industry. Technically feasible processes that are commercially available for the concentration of liquid foods include evaporation, freeze concentration, reverse osmosis, and ultrafiltration. Evaporation is considered to be the most economical and most widely used method of concentration. However, it is not suited for food products with very delicate flavors. Commercial processes for the concentration of such products by membrane separation techniques are not yet available. As compared to the conventional evaporation processes, concentration by freezing is potentially a superior and economic process for aroma-rich liquid foods. In the past, the process, however, was seldom used because of the investment cost and the considerable loss of concentrate in the withdrawn ice, and hence, the quality. Recent technological developments have minimized these two drawbacks associated with the earlier freeze concentration processes. In the coming decade, freeze concentration is seen as a potentially attractive method for the concentration of aroma-rich liquid foods, including fruit juices, coffee, tea, and selected alcoholic beverages. In this article, several aspects of the theoretical considerations behind freeze concentration of fruit juices, the development of new and cheaper designs, and commercially available freeze concentration processes are reviewed. The economics of the process and its application to several other areas of the food industry are also discussed. PMID:6383717

  20. USE OF VARIOUS BAITS FOR EXTRACTION OF EARTHWORMS FROM VERMICOMPOST

    OpenAIRE

    Joanna Kostecka; Vinod Kumar Garg

    2015-01-01

    During vermicomposting, earthworm grower has to overcome a lot of different problems. For instance, in case of a sudden requirement to sell earthworms it is useful to have the ability to collect them in one place. Fresh food extraction is an effective and neutral way to do it. The efficiency of gathering and extracting E. fetida from the vermicompost was studied, using a fresh bait method. Experiments were carried out in the laboratory (at the mean temperature of 200.5 C) in pots filled wit...

  1. Toxicity of Commercial Neem Extract to Earthworms (Pheretima peguana)

    OpenAIRE

    Ravi Gooneratne; Ptumporn Muangphra

    2011-01-01

    The LC50 of commercial neem extract (Sadao Thai III containing azadirachtin; NEEM) on filter paper in the earthworm Pheretima peguana at 48?h and 72?h was 3.79 and 3.33? g? c m ? 2 , respectively. In earthworms exposed to five NEEM concentrations from 0.39 (~10% of 48-h LC50) to 3.13 (~80% of 48-h LC50) g? c m ? 2 , the radial thickness of the epidermis and body wall significantly ( < . 0 5 ) decreased, and thickness of intestinal epithelium increased but only at high doses, approximate...

  2. MicroRNA regulation in heart and skeletal muscle over the freeze-thaw cycle in the freeze tolerant wood frog.

    Science.gov (United States)

    Bansal, Saumya; Luu, Bryan E; Storey, Kenneth B

    2016-02-01

    The North American wood frog, Rana sylvatica, is one of just a few anuran species that tolerates whole body freezing during the winter and has been intensely studied to identify the biochemical adaptations that support freeze tolerance. Among these adaptations is the altered expression of many genes, making freeze-responsive changes to gene regulatory mechanisms a topic of interest. The present study focuses on the potential involvement of microRNAs as one such regulatory mechanism and aims to better understand freeze/thaw stress-induced microRNA responses in the freeze-tolerant wood frog. Using quantitative PCR, relative levels of 53 microRNAs were measured in heart and skeletal muscle of control, 24h frozen, and 8h thawed frogs. MicroRNAs showed tissue specific expression patterns: 21 microRNAs decreased in the heart during thawing, whereas 16 microRNAs increased during freezing stress in skeletal muscle. These findings suggest that select genes may be activated and suppressed in heart and skeletal muscle, respectively, in response to freezing. Bioinformatics analysis using the DIANA miRPath program (v.2.0) predicted that the differentially expressed microRNAs may collectively regulate tissue-specific cellular pathways to promote survival of wood frogs undergoing freezing and thawing. PMID:26660652

  3. OPTIMIZATION OF COMPOSITION CULTURE MEDIA, TECHNIQUE OF CONCENTRATING AND FREEZE DRYING CONDITIONS FOR CELL OF LACTOBACILLUS ACIDOPHILUS

    Directory of Open Access Journals (Sweden)

    Lysenko Y. A.

    2014-10-01

    Full Text Available This study has investigated the relationship between culture media, technique of concentrating and freeze drying conditions for the cells of Lactobacillus aci-dophilus. The study has demonstrated that milk whey tomato juice-enriched medium has the high-growth properties. This medium allows ensuring high freeze drying survival of Lactobacillus acidophilus

  4. Abundance, Biomass and Vertical Distribution of Earthworms in Ecosystem Units of Hornbeam Forest

    Directory of Open Access Journals (Sweden)

    Y. Kooch

    2008-01-01

    Full Text Available The objectives of this study were to investigate the abundance, biomass and practical distribution of earthworms in ecosystem and tried to identify the factors affecting earthworm populations during different environmental conditions. Density and biomass of earthworms were studied in ecosystem unit`s khanikan forests (North of Iran in July 2006. Eighteen soil profiles (50x50 cm to the depth of 30 cm were digged and soil samples were taken from organic horizon (litter layer and mineral layers (0-10, 10-20 and 20-30 cm. Earthworms were collected by hand sorting method, then oven-dried at 60C and weighed. Comparison number and biomass of earthworms in various layers of soil have showed that most number was in third layer (63.63% and the least number was in second layer (13.63%. Also, biomass of earthworms in third layer was the most (79.39% and was the least in second layer (7.57%. Results of this research indicated that correlation between number and biomass of earthworms with C/N, biomass of earthworms with carbon of soil and number of earthworms with theirs biomass were significant. Correlation between number and biomass of earthworms with the other soil properties investigated was no significant.

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

    International Nuclear Information System (INIS)

    The influence of earthworm activity on soil-to-plant metal transfer was studied by carrying out six weeks mesocosms experiments with or without lettuce and/or earthworms in soil with a gradient of metal concentrations due to particles fallouts. Soil characteristics, metal concentrations in lettuce and earthworms were measured and soil porosity in the mesocosms was determined. Earthworms increased the soil pH, macroporosity and soil organic matter content due to the burying of wheat straw provided as food. Earthworm activities increased the metals concentrations in lettuce leaves. Pb and Cd concentrations in lettuce leaves can increase up to 46% with earthworm activities These results and the low correlation between estimated by CaCl2 and EDTA and measured pollutant phytoavailability suggest that earthworm bioturbation was the main cause of the increase. Bioturbation could affect the proximity of pollutants to the roots and soil organic matter. - Highlights: Earthworm bioturbation increases phytoavailability of Pb, Cd, Zn and Cu. Earthworm activity influences soil structure and increases pH. Plant metal uptake was not correlated with CaCl2, EDTA estimated phytoavailability. Increased metal phytoavailability with bioturbation could increase human exposure. - Earthworm activities can increase metal phytoavailability and subsequent human exposure to metals in consumed vegetables

  6. Arsenic resistance and cycling in earthworms residing at a former gold mine in Canada

    International Nuclear Information System (INIS)

    Earthworms (Lumbricus castaneous and Dendrodrilus rubidus), their host soils and leaf litter were collected from a former gold mine with widespread arsenic (As) contamination in Nova Scotia, Canada and determined for total and speciated As. Resistance to As toxicity was investigated by measurement of DNA damage in exposed earthworm populations using the comet assay. Arsenobetaine (AB) was observed at low concentration in the earthworms but not in the host soil or leaf litter. Several different organoarsenic species were observed in the leaf litter and only inorganic As was found in the host soils. The results suggest that 1) adaptation to As toxicity in earthworms is widespread and not particular to a single species, 2) AB originates in the earthworm and not the consumed soil or leaf litter and 3) as previously hypothesised (), biotransformation of inorganic As to AB is not likely involved in the adaptation. - Highlights: ► Adaptation to toxicity and cycling of arsenic in earthworms investigated at Canadian gold mine. ► Earthworms resistant to highly contaminated, genotoxic soils. ► Arsenobetaine present in earthworms but not soil or leaf litter. ► Arsenic resistance in earthworms is widespread and not species specific. - Adaptation of earthworms to arsenic contaminated soils is widespread and not species specific.

  7. Invasion by Exotic Earthworms Alters Biodiversity and Communities of Litter- and Soil-dwelling Oribatid Mites

    Directory of Open Access Journals (Sweden)

    John C. Maerz

    2011-03-01

    Full Text Available Exotic earthworms are drivers of biotic communities in invaded North American forest stands. Here we used ecologically important oribatid mite (Arachnida: Acari communities, as model organisms to study the responses of litter- and soil-dwelling microarthropod communities to exotic earthworm invasion in a northern temperate forest. Litter- and soil-dwelling mites were sampled in 20082009 from forest areas: (1 with no earthworms; (2 those with epigeic and endogeic species, including Lumbricus rubellus Hoffmeister; and (3 those with epigeic, endogeic, and anecic earthworms including L.terrestris L. Species richness and diversity of litter- and soil-dwelling (02 cm soil depth oribatid mites was 12 times higher in sites without earthworms than in sites with worms. Similarly, litter-dwelling oribatid mites were between 72 and 1,210 times more abundant in earthworm-free sites than in sites with worms. Among earthworm invaded sites, abundance of litter-dwelling oribatid mites in sites without the anecic L. terrestris was twice as high in May and 28 times higher in October, compared to sites with L.terrestris. Species richness, diversity, and abundance of oribatid mites were greater in litter-layers than in the soil-layers that showed a varied response to earthworm invasion. Species compositions of both litter- and soil-dwelling oribatid mite communities of forests with no earthworms were markedly different from those with earthworms. We conclude that exotic earthworm invasions are associated with significant declines of species diversity, numbers, and compositional shifts in litter- and soil-inhabiting communities. These faunal shifts may contribute to earthworm effects on soil processes and food web dynamics in historically earthworm-free, northern temperate forests.

  8. Size structure of earthworms populations and the theory of neutrality

    Directory of Open Access Journals (Sweden)

    O. ?. Kunah

    2007-02-01

    Full Text Available The paper points that neutrality theory allows to describe a distribution of earthworms body weight classes in the population. The statistical parameters can be interpreted in terms of the population ecology. The dynamics of parameters distribution over seasons and under anthropogenic impact demonstrates that sense assigned to the distribution parameters is very close to real processes in animal population.

  9. Does the microbial environment determine innate immunity in earthworms?.

    Czech Academy of Sciences Publication Activity Database

    Bilej, Martin; Dvo?k, Ji?; Man?kov, Veronika; ilerov, Marcela; Prochzkov, Petra; Roubalov, Radka; kanta, Frantiek; Elhottov, Dana; Koubov, Anna; Pil, Vclav

    ?esk Bud?jovice : Institute of Soil Biology, BC ASCR, 2013. s. 13. ISBN 978-80-86525-23-5. [Central European Workshop on Soil Zoology /12./. 08.04.2013-11.04.2013, ?esk Bud?jovice] Institutional support: RVO:60077344 ; RVO:61388971 Keywords : microbial environment * innate immunity * earthworms Subject RIV: EC - Immunology

  10. Earthworms in an arable field-forest ecotone.

    Czech Academy of Sciences Publication Activity Database

    Pil, Vclav; Zeithaml, J.

    ?esk Bud?jovice : Institute of Soil Biology AS CR, 2003. s. 48. [Central European Workshop on Soil Zoology /7./. 14.04.2003-16.04.2003, ?esk Bud?jovice] Institutional research plan: CEZ:AV0Z6066911 Keywords : earthworms * field-forest ecotone Subject RIV: EH - Ecology, Behaviour

  11. Identification and expression analysis of calreticulin in Eisenia fetida earthworms.

    Czech Academy of Sciences Publication Activity Database

    ilerov, Marcela; Kauschke, E.; Kohlerov, Petra; Joskov, Radka; Tu?kov, Ludmila; Bilej, Martin

    Paris : EFIS, 2006, s. 46-46. [European Congress of Immunology /16./. Paris (FR), 06.09.2006-09.09.2006] R&D Projects: GA ?R GD310/03/H147; GA AV ?R IAA5020208; GA Mk 2B06155 Institutional research plan: CEZ:AV0Z50200510 Keywords : calreticulin * earthworms * eisenia fetida Subject RIV: EE - Microbiology, Virology

  12. Endogeic earthworms can increase CO2 accumulation in soil.

    Czech Academy of Sciences Publication Activity Database

    imek, Miloslav; Pil, Vclav

    ?esk Bud?jovice : Institute of Soil Biology BC AS CR, 2009. s. 76. [Central European Workshop on Soil Zoology /10./. 21.04.2009-24.04.2009, ?esk Bud?jovice] Institutional research plan: CEZ:AV0Z60660521 Keywords : endogeic earthworms * CO 2 accumulation * soil Subject RIV: EH - Ecology, Behaviour

  13. Diversity and host specificity of the Verminephrobacterearthworm symbiosis

    DEFF Research Database (Denmark)

    Lund, Marie Braad; Davidson, Seana

    2010-01-01

    Symbiotic bacteria of the genus Verminephrobacter (Betaproteobacteria) were detected in the nephridia of 19 out of 23 investigated earthworm species (Oligochaeta: Lumbricidae) by 16S rRNA gene sequence analysis and fluorescence in situ hybridization (FISH). While all four Lumbricus species and three out of five Aporrectodea species were densely colonized by a mono-species culture of Verminephrobacter, other earthworm species contained mixed bacterial populations with varying proportions of Verminephrobacter; four species did not contain Verminephrobacter at all. The Verminephrobacter symbionts could be grouped into earthworm species-specific sequence clusters based on their 16S rRNA and RNA polymerase subunit B (rpoB) genes. Closely related host species harboured more closely related symbionts than did distantly related hosts. Co-diversification of the symbiotic partners could not be demonstrated unambiguously due to the poor resolution of the host phylogeny [based on histone H3 and cytochrome c oxidase subunit I (COI) gene sequence analyses]. However, there was a pattern of symbiont diversification within four groups of closely related hosts. The mean rate of symbiont 16S rRNA gene evolution was determined using a relaxed clock model, and the rate was calibrated with paleogeographical estimates of the time of origin of Lumbricid earthworms. The calibrated rates of symbiont 16S rRNA gene evolution are 0.0120.026 substitutions per site per 50 million years and thus similar to rates reported from other symbiotic bacteria.

  14. Non-self recognition in Eisenia fetida earthworms.

    Czech Academy of Sciences Publication Activity Database

    Kohlerov, Petra; ilerov, Marcela; Felsberg, Jrgen; Joskov, Radka; Josens, G.; Beschin, A.; De Baetselier, P.; Bilej, Martin

    Paris : EFIS, 2006, s. 47-47. [European Congress of Immunology /16./. Paris (FR), 06.09.2006-09.09.2006] R&D Projects: GA Mk 2B06155; GA AV ?R KJB500200613 Institutional research plan: CEZ:AV0Z50200510 Keywords : coelomic cytolytic factor * earthworms * eisenia fetida Subject RIV: EE - Microbiology, Virology

  15. Distribution of earthworms (Lumbricidae) in Bohemian Switzerland (Czech Republic).

    Czech Academy of Sciences Publication Activity Database

    Pil, Vclav

    Praha : Academia, 2007 - (Hartel, H.; Clek, V.; Herben, T.; Jackson, A.; Williams, R.), s. 147-150 ISBN 978-80-200-1577-8 Institutional research plan: CEZ:AV0Z60660521 Keywords : earthworms * soil fauna * sandstone area Subject RIV: EH - Ecology, Behaviour

  16. Earthworm's immunity in the nanomaterial world: new room, future challenges

    DEFF Research Database (Denmark)

    Hayashi, Yuya; Engelmann, Pter

    2013-01-01

    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 on invertebrate immunity is limited to only a handful of initial studies including those on earthworms. Recently, we reported selective accumulation of silver nanoparticles in the amoebocyte population of Eisenia fetida coelomocytes in vitro. In this review, we give an overview of available literature on the life-history impacts on earthworms, and what we have learnt of the immune responses to nanoparticles with references to other invertebrate species and vertebrate counterparts. We discuss the significant contribution of amoebocytes as nanoparticle scavengers and suggest a possibility of studying inter-cellular communications in coelomocytes. Implications from the leading researches in vertebrate models tell us that study of the nanoparticle recognition involved in cellular uptake as well as sub- and inter-cellular events may uncover further intriguing insights into earthworms immunity in the nanomaterial world.

  17. Diversity and host specificity of the Verminephrobacterearthworm symbiosis

    DEFF Research Database (Denmark)

    Lund, Marie Braad; Davidson, Seana; Holmstrup, Martin; James, Sam; Kjeldsen, Kasper Urup; Stahl, David; Schramm, Andreas

    2010-01-01

    Symbiotic bacteria of the genus Verminephrobacter (Betaproteobacteria) were detected in the nephridia of 19 out of 23 investigated earthworm species (Oligochaeta: Lumbricidae) by 16S rRNA gene sequence analysis and fluorescence in situ hybridization (FISH). While all four Lumbricus species and th...

  18. Impact of PCDD/PCDFs on the earthworm Eisenia andrei

    Czech Academy of Sciences Publication Activity Database

    Roubalov, Radka; Dvo?k, Ji?; Prochzkov, Petra; Elhottov, Dana; Rossmann, Pavel; kanta, Frantiek; Bilej, Martin

    Athens : United States Department of Agriculture , 2014. s. 34. [International Symposium on Earthworm Ecology /10./. 22.06.2014-27.06.2014, Athens] Institutional support: RVO:60077344 ; RVO:61388971 Keywords : impact of PCDD/PCDFs * Eisenia andrei Subject RIV: EH - Ecology, Behaviour

  19. Low-temperature microRNA expression in the painted turtle, Chrysemys picta during freezing stress.

    Science.gov (United States)

    Biggar, Kyle K; Storey, Kenneth B

    2015-11-30

    Natural freeze tolerance depends on cellular adaptations that address the multiple stresses imposed on cells during freezing. These adaptations preserve viability by suppressing energy-expensive cell processes in the frozen state. In this study, we explore the freeze-responsive expression of microRNA in hatchling painted turtles exposed to 20h freezing. Furthermore, we also explore the possibility of unique temperature-sensitive microRNA targeting programs that aid in adapting turtles for survival in the frozen state. Interestingly, two freeze-responsive 'cryo-miRs' (cpm-miR-16 and cpm-miR-21) were found to have unique low-temperature mRNA targets enriched in biological processes that are known to be part of the stress response. PMID:26519560

  20. Freeze Protection in Gas Holders

    DEFF Research Database (Denmark)

    Hjorth, Poul G.; Duursma, Gail

    2008-01-01

    In cold weather, the water seals of gasholders need protection from freez- ing to avoid compromising the seal. These holders have a large reservoir of tank water at the base which is below ground. At present freeze- protection is achieved by external heating of the seal water which is in a slotted channel called a cup. Electrical heating or circulation of heated tank water to the cup are examples of systems presently used. The tank water has a large thermal capacity and National Grid wishes to inves- tigate whether circulation of the tank water without external heating could provide su?cient energy input to avoid freezing. Only tanks in which the tank water is below ground are investigated in the report. The soil temperature under the reservoir at depth of 10m and lower is almost constant.

  1. Freezing singularities in water drops

    CERN Document Server

    Enriquez, Oscar R; Winkels, Koen G; Snoeijer, Jacco H

    2011-01-01

    In this fluid dynamics video we show how a drop of water freezes into a singular shape when deposited on a cold surface. The process of solidification can be observed very clearly due to the change in refraction when water turns into ice. The drop remains approximately spherical during most of the process, with a freezing front moving upwards and smoothly following the interface. However, at the final stage of freezing, when the last cap of liquid turns into ice, a singular tip develops spontaneously. Interestingly, the sharp tip of the ice drop acts as a preferential site for deposition of water vapour, and a beautiful "tree" of ice crystals develops right at the tip. The tip singularity attracts the vapour in analogy to a sharp lightning rod attracting lightning.

  2. Water Freezing and Ice Melting.

    Science.gov (United States)

    Ma?olepsza, Edyta; Keyes, Tom

    2015-12-01

    The generalized replica exchange method (gREM) is designed to sample states with coexisting phases and thereby to describe strong first order phase transitions. The isobaric MD version of the gREM is presented and applied to the freezing of liquid water and the melting of hexagonal and cubic ice. It is confirmed that coexisting states are well-sampled. The statistical temperature as a function of enthalpy, TS(H), is obtained. Hysteresis between freezing and melting is observed and discussed. The entropic analysis of phase transitions is applied and equilibrium transition temperatures, latent heats, and surface tensions are obtained for hexagonal ice ? liquid and cubic ice ? liquid with excellent agreement with published values. A new method is given to assign water molecules among various symmetry types. Pathways for water freezing, ultimately leading to hexagonal ice, are found to contain intermediate layered structures built from hexagonal and cubic ice. PMID:26642983

  3. Freeze Protection in Gas Holders

    DEFF Research Database (Denmark)

    Hjorth, Poul G.; Duursma, Gail

    In cold weather, the water seals of gasholders need protection from freez- ing to avoid compromising the seal. These holders have a large reservoir of “tank water” at the base which is below ground. At present freeze- protection is achieved by external heating of the seal water which is in a...... slotted channel called a cup. Electrical heating or circulation of heated tank water to the cup are examples of systems presently used. The tank water has a large thermal capacity and National Grid wishes to inves- tigate whether circulation of the tank water without external heating could provide...... sufficient energy input to avoid freezing. Only tanks in which the tank water is below ground are investigated in the report. The soil temperature under the reservoir at depth of 10m and lower is almost constant....

  4. Freeze-in through portals

    CERN Document Server

    Blennow, Mattias; Zaldivar, Bryan

    2014-01-01

    The popular freeze-out paradigm for Dark Matter (DM) production, relies on DM-baryon couplings of the order of the weak interactions. However, different search strategies for DM have failed to provide a conclusive evidence of such (non-gravitational) interactions, while greatly reducing the parameter space of many representative models. This motivates the study of alternative mechanisms for DM genesis. In the freeze-in framework, the DM is slowly populated from the thermal bath while never reaching equilibrium. In this work, we analyse in detail the possibility of producing a frozen-in DM via a mediator particle which acts as a portal. We give analytical estimates of different freeze-in regimes and support them with full numerical analyses, taking into account the proper distribution functions of bath particles. Finally, we constrain the parameter space of generic models by requiring agreement with DM relic abundance observations.

  5. Do earthworms impact metal mobility and availability in soil? - A review

    Energy Technology Data Exchange (ETDEWEB)

    Sizmur, Tom, E-mail: t.p.sizmur@reading.ac.u [Department of Soil Science, University of Reading, Whiteknights, Reading RG6 6DW (United Kingdom); Hodson, Mark E., E-mail: m.e.hodson@reading.ac.u [Department of Soil Science, University of Reading, Whiteknights, Reading RG6 6DW (United Kingdom)

    2009-07-15

    The importance of earthworms to ecosystem functioning has led to many studies on the impacts of metals on earthworms. Far less attention has been paid to the impact that earthworms have on soil metals both in terms of metal mobility and availability. In this review we consider which earthworms have been used in such studies, which soil components have been investigated, which types of soil have been used and what measures of mobility and availability applied. We proceed to review proposed reasons for effects: changes in microbial populations, pH, dissolved organic carbon and metal speciation. The balance of evidence suggests that earthworms increase metal mobility and availability but more studies are required to determine the precise mechanism for this. - We review the impact of earthworms on metal mobility and availability and suggest areas for further investigation.

  6. Heavy Metals Bioaccumulation by Iranian and Australian Earthworms (Eisenia fetida in the Sewage Sludge Vermicomposting

    Directory of Open Access Journals (Sweden)

    MR Shahmansouri, H Pourmoghadas, AR Parvaresh, H Alidadi

    2005-01-01

    Full Text Available Vermicomposting of organic waste has an important part to play in an integrated waste management strategy. In this study, the possibility of heavy metals accumulation with two groups of Iranian and Australian earthworms in sewage sludge vermicompost was investigated. Eisenia fetida was the species of earthworms used in the vermicomposting process. The bioaccumulation of Cr, Cd, Pb, Cu, and Zn as heavy metals by Iranian and Australian earthworms was studied. The results indicated that heavy metals concentration decreased with increasing vermicomposting time. Comparison of the two groups of earthworms showed that the Iranian earthworms consumed higher quantities of micronutrients such as Cu and Zn comparing with the Australian earthworms, while the bioaccumulation of non-essential elements such as Cr, Cd, and Pb by the Australian group was higher. The significant decrease in heavy metal concentrations in the final vermicompost indicated the capability of both Iranian and Australian E.fetida species in accumulating heavy metals in their body tissues.

  7. Co-Speciationof Earthwormsandtheirnephridial symbionts, Acidovorax Spp

    DEFF Research Database (Denmark)

    Lund, Marie Braad; Fritz, Michael; Holmstrup, Martin; Schramm, Andreas

    2006-01-01

    Earthworms (Annelida; Lumbricidae) harbour species-specific symbiotic bacteria in their nephridia (excretory organs) where the symbionts densely colonize a specific part of the nephridia called the ampulla [1]. The symbiosis is universal among earthworms, the symbionts form a monophyletic cluster...... within the genus Acidovorax [2], and they are transmitted vertically [3]. For these reasons, we suggest that the earthworm-Acidovorax association has evolved by co-speciation. This hypothesis was tested by a comparative study of earthworm and symbiont phylogeny. Different earthworm species were collected...... in Denmark and DNA was extracted from their nephridia. Earthworm phylogeny was resolved on the basis of mitochondrial cytochrome c oxidase subunit I (COI) by direct PCR amplification and sequencing from the nephridial DNA extract. Symbiont 16S rRNA gene sequences were retrieved by cloning and...

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

    Science.gov (United States)

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

    2007-01-01

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

  9. Do earthworms impact metal mobility and availability in soil? - A review

    International Nuclear Information System (INIS)

    The importance of earthworms to ecosystem functioning has led to many studies on the impacts of metals on earthworms. Far less attention has been paid to the impact that earthworms have on soil metals both in terms of metal mobility and availability. In this review we consider which earthworms have been used in such studies, which soil components have been investigated, which types of soil have been used and what measures of mobility and availability applied. We proceed to review proposed reasons for effects: changes in microbial populations, pH, dissolved organic carbon and metal speciation. The balance of evidence suggests that earthworms increase metal mobility and availability but more studies are required to determine the precise mechanism for this. - We review the impact of earthworms on metal mobility and availability and suggest areas for further investigation.

  10. Earthworms, soil aggregates and organic matter decomposition in agro-ecosystems in The Netherlands.

    OpenAIRE

    Marinissen, J.C.Y.

    1995-01-01

    The relationships between earthworm populations, soil aggregate stability and soil organic matter dynamics were studied at an experimental farm in The Netherlands.Arable land in general is not favourable for earthworm growth. In the Lovinkhoeve fields under conventional management earthworm populations were brought to the verge of extinction in a few years. Main causes are soil fumigation against nematodes and unfavourable food conditions. Organic matter inputs and N-contents of the organic m...

  11. Heavy Metals Bioaccumulation by Iranian and Australian Earthworms (Eisenia fetida) in the Sewage Sludge Vermicomposting

    OpenAIRE

    MR Shahmansouri, H Pourmoghadas, AR Parvaresh, H Alidadi

    2005-01-01

    Vermicomposting of organic waste has an important part to play in an integrated waste management strategy. In this study, the possibility of heavy metals accumulation with two groups of Iranian and Australian earthworms in sewage sludge vermicompost was investigated. Eisenia fetida was the species of earthworms used in the vermicomposting process. The bioaccumulation of Cr, Cd, Pb, Cu, and Zn as heavy metals by Iranian and Australian earthworms was studied. The results indicated that heavy me...

  12. Valorisation of a water hyacinth in vermicomposting using an epigeic earthworm Perionyx excavatus in Central Vietnam

    OpenAIRE

    Zirbes, L.; Renard, Q.; Dufey, J; Tu, PK.; Duyet, HN.; Lebailly, P.; Francis, F.; Haubruge, E.

    2011-01-01

    The feasibility of vermicomposting water hyacinth (WH) [Eichhornia crassipes (Mart.) Solms] mixed with pig manure (PM) in different proportions was tested using tropical composting earthworm Perionyx excavatus. Earthworms grew and reproduced normally until the incorporation of 50% WH in initial substrate. Higher water hyacinth proportions induced earthworms' mortality and significantly affected the numbers of hatchlings and cocoons produced during vermicomposting period. The influence of the ...

  13. Associations between soil texture, soil water characteristics and earthworm populations of grassland

    DEFF Research Database (Denmark)

    Holmstrup, Martin; Lamand, Mathieu; Torp, Sren Bent; Labouriau, Rodrigo; Greve, Mogens Humlekrog; Heckrath, Goswin

    2011-01-01

    The aim of the present study was to investigate the relationships between soil physical characteristics and earthworms in a regional-scale field study in Denmark. The earthworm populations along within-field gradients in soil texture were quantified at five field sites, representing dominant soil types of Denmark. Eleven earthworm species were found, but populations were mainly dominated by Aporrectodea tuberculata and A. longa. Despite considerable variation in soil parameters across the five s...

  14. Impact of earthworms on the diversity of microarthropods in a vertisol (Martinique)

    OpenAIRE

    Loranger, Gladys; Ponge, Jean-Franois; Blanchart, ric; LAVELLE, Patrick

    1998-01-01

    In a study of a 15-year-old pasture in Martinique (French West Indies), abundance and organization of microarthropod communities were correlated with the spatial distribution of the earthworm #Polypheretima elongata$ (Megascolecidae). In patches of high earthworm density (133 individuals/sq m), microarthropod density was significantly higher (80 000 individuals/sq m) than in patches with few earthworms (31 worms/sq m and 49 000 microarthropods/sq m). The diversity of microarthropod communitie...

  15. Invasion by Exotic Earthworms Alters Biodiversity and Communities of Litter- and Soil-dwelling Oribatid Mites

    OpenAIRE

    Maerz, John C.; Milanovich, Joseph R.; Gandhi, Kamal J.K.; Melany C. Fisk; Burke, Jordan L.

    2011-01-01

    Exotic earthworms are drivers of biotic communities in invaded North American forest stands. Here we used ecologically important oribatid mite (Arachnida: Acari) communities, as model organisms to study the responses of litter- and soil-dwelling microarthropod communities to exotic earthworm invasion in a northern temperate forest. Litter- and soil-dwelling mites were sampled in 20082009 from forest areas: (1) with no earthworms; (2) those with epigeic and endogeic species, including Lumbric...

  16. Earthworm transport of heavy metals from sewage sludge: a micro-PIXE application in soil science

    Science.gov (United States)

    Protz, R.; Teesdale, W. J.; Maxwell, J. A.; Campbell, J. L.; Duke, C.

    1993-05-01

    Micro-PIXE was used to analyze earthworm fecal material and the linings of earthworm channels in the soil below a land area on which sewage sludge had been applied. Metals present in the sludge were identified both in fecal pellets and in the linings of the channels, at concentration markedly higher than in the soil matrix. PIXE elemental data in raster format were spatially analyzed during image analysis demonstrating in a quantitative manner the spatial correlations among elements transported by the earthworms.

  17. Effects of Pesticides on the Growth and Reproduction of Earthworm: A Review

    OpenAIRE

    Doris D'Souza; Shahla Yasmin

    2010-01-01

    Scientific literature addressing the influence of pesticides on the growth and reproduction of earthworm is reviewed. Earthworms are considered as important bioindicators of chemical toxicity in the soil ecosystem. Studies on this aspect are important because earthworms are the common prey of many terrestrial vertebrate species such as birds and small mammals, and thus they play a key role in the biomagnification process of several soil pollutants. Majority of the studies have used mortality ...

  18. Impacts of epigeic, anecic and endogeic earthworms on metal and metalloid mobility and availability

    OpenAIRE

    Sizmur, Tom; Tilston, Emma L.; Charnock, John; Palumbo-Roe, Barbara; Michael J. Watts; Hodson, Mark E.

    2011-01-01

    The introduction of earthworms into soils contaminated with metals and metalloids has been suggested to aid restoration practices. Eisenia veneta (epigeic), Lumbricus terrestris (anecic) and Allolobophora chlorotica (endogeic) earthworms were cultivated in columns containing 900 g soil with 1130, 345, 113 and 131 mg kg1 of As, Cu, Pb and Zn, respectively, for up to 112 days, in parallel with earthworm-free columns. Leachate was produced by pouring water on the soil surface to satu...

  19. Impact of soil management on earthworm diversity according to differential plowing and plant residue incorporation

    OpenAIRE

    Lemtiri, Aboulkacem; Alabi, Taofic; Zirbes, Lara; Bodson, Bernard; Brostaux, Yves; Colinet, Gilles; Destain, Marie-France; Aubinet, Marc; Vandenbol, Micheline; Portetelle, Daniel; Haubruge, Eric; Francis, Frdric

    2012-01-01

    Earthworms are largely distributed in terrestrial ecosystems and their abundance and diversity in soils are significantly affected by biotic (macro- and micro-organisms) and abiotic factors: soil properties (pH, texture, structure); agricultural management system and climate change. Here, tillage effect of earthworm population combined with crops residual management was investigated and correlated with soils properties. From wheat experimental field plots, the diversity of earthworm accordin...

  20. Soil pH governs production rate of calcium carbonate secreted by the earthworm Lumbricus terrestris

    OpenAIRE

    Lambkin, Denise C.; Gwilliam, K. H.; Layton, C; Canti, M. G.; Piearce, T. G.; Hodson, Mark E.

    2011-01-01

    Lumbricus terrestris earthworms exposed to 11 soils of contrasting properties produced, on average, 0.8 0.1 mgCaCO3 earthworm?1 day?1 in the form of granules up to 2 mm in diameter. Production rate increased with soil pH (r2 = 0.68, p < 0.01). Earthworms could be a significant source of calcite in soils.

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

    OpenAIRE

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

    2005-01-01

    To investigate the impact of copper-containing fungicides (copper oxychloride) on earthworms in South African vineyards, field inventories of earthworms in and between vine rows were carried out and compared to directly adjacent grassland. Also copper content, pH, organic matter content, and soil porosity were determined in these soils. This was combined with laboratory experiments to study the impact of vineyard soil characteristics on the burrowing and dispersal behavior of earthworms. More...

  2. Earthworms as colonisers: Primary colonisation of contaminated land, and sediment and soil waste deposits

    OpenAIRE

    Eijsackers, H.J.P.

    2010-01-01

    This paper reviews the role of earthworms in the early colonisation of contaminated soils as well as sediment and waste deposits, which are worm-free because of anthropogenic activities such as open-cast mining, soil sterilisation, consistent pollution or remediation of contaminated soil. Earthworms live in close interaction with their soil environment and are able to change it considerably by their burrowing and litter comminuting behaviour. While earthworms have been studied extensively, se...

  3. Potential utilization of bagasse as feed material for earthworm Eisenia fetida and production of vermicompost.

    Science.gov (United States)

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

    2015-01-01

    In the present work bagasse (B) i.e waste of the sugar industry, was fed to Eisenia fetida with cattle dung (CD) support as feed material at various ratios (waste: CD) of 0:100 (B0), 25:75 (B25), 50:50 (B50), 75:25 (B75) and 100:0 (B100) on dry weight basis. Co-composting with cattle dung helped to improve their acceptability for E. fetida and also improved physico-chemical characteristics. Best appropriate ratio for survival, maximum growth and population buildup of E. fetida was determined by observing population buildup, growth rate, biomass, mortality and cocoon formation. Minimum mortality and highest population size of worms was observed in 50:50 (B50) ratio. Increasing concentrations of wastes significantly affected the growth and reproduction of worms. Nutrients like nitrogen, phosphorus and sodium increased from pre-vermicompost to post-vermicompost, while organic carbon, and C:N ratio decreased in all the end products of post-vermicomposting. Heavy metals decreased significantly from initial except zinc, iron and manganese which increased significantly. Scanning electron microscopy (SEM) was used to recognize the changes in texture in the pre and post-vermicomposted samples. The post-vermicomposted ratios in the presence of earthworms validate more surface changes that prove to be good manure. The results observed from the present study indicated that the earthworm E. fetida was able to change bagasse waste into nutrient-rich manure and thus play a major role in industrial waste management. PMID:25625035

  4. Population genetics of freeze tolerance among natural populations of Populus balsamifera across the growing season.

    Science.gov (United States)

    Menon, Mitra; Barnes, William J; Olson, Matthew S

    2015-08-01

    Protection against freeze damage during the growing season influences the northern range limits of plants. Freeze tolerance and freeze avoidance are the two major freeze resistance strategies. Winter survival strategies have been extensively studied in perennials, but few have addressed them and their genetic basis during the growing season. We examined intraspecific phenotypic variation in freeze resistance of Populus balsamifera across latitude and the growing season. To investigate the molecular basis of this variation, we surveyed nucleotide diversity and examined patterns of gene expression in the poplar C-repeat binding factor (CBF) gene family. Foliar freeze tolerance exhibited latitudinal and seasonal variation indicative of natural genotypic variation. CBF6 showed signatures of recent selective sweep. Of the 46 SNPs surveyed across the six CBF homologs, only CBF2_619 exhibited latitudinal differences consistent with increased freeze tolerance in the north. All six CBF genes were cold inducible, but showed varying patterns of expression across the growing season. Some Poplar CBF homologs exhibited patterns consistent with historical selection and clinal variation in freeze tolerance documented here. However, the CBF genes accounted for only a small amount of the variation, indicating that other genes in this and other molecular pathways likely play significant roles in nature. PMID:25809016

  5. Time dependence of immersion freezing

    Directory of Open Access Journals (Sweden)

    A. Welti

    2012-05-01

    Full Text Available The time dependence of immersion freezing was studied for temperatures between 236 K and 243 K. Droplets with single immersed, size-selected 400 nm and 800 nm kaolinite particles were produced at 300 K, cooled down to supercooled temperatures typical for mixed-phase cloud conditions, and the fraction of frozen droplets with increasing residence time was detected. To simulate the conditions of immersion freezing in mixed-phase clouds we used the Zurich Ice Nucleation Chamber (ZINC and its vertical extension, the Immersion Mode Cooling chAmber (IMCA. We observed that the frozen fraction of droplets increased with increasing residence time in the chamber. This suggests that there is a time dependence of immersion freezing and supports the importance of a stochastic component in the ice nucleation process. The rate at which droplets freeze was observed to decrease towards higher temperatures and smaller particle sizes. Comparison of the laboratory data with four different ice nucleation models, three based on classical nucleation theory with different representations of the particle surface properties and one singular, suggest that the classical, stochastic approach combined with a distribution of contact angles is able to reproduce the ice nucleation observed in these experiments most accurately. Using the models to calculate the increase in frozen fraction at typical mixed-phase cloud temperatures over an extended period of time, yields an equivalent effect of ?1 K temperature shift and an increase in time scale by a factor of ~10.

  6. Earthworms - role in soil fertility to the use in medicine and as a food

    Directory of Open Access Journals (Sweden)

    M Grdia

    2013-04-01

    Full Text Available Earthworms are important regulators of soil structure and dynamics of soil organic matter. They are a major component of soil fauna communities in most ecosystems and comprise a large proportion of macro fauna biomass. Their activities are beneficial because they can enhance soil nutrient cycling through the rapid incorporation of detritus into mineral soil. However, mucus production associated with water excretion in earthworm guts also enhances the activity of other beneficial soil microorganisms. Earthworms alter soil structure, water movement, nutrient dynamics and plant growth. The medical value of earthworms has been known for centuries. The extracts prepared from earthworm tissues have been used for the treatment of numerous diseases since they are valuable source of proteins, peptides, enzymes and physiologically active substances. Several studies have shown that the earthworm extracts contain different macromolecules which exhibited the variety of activities, such as antioxidative, antibacterial, antiinflammatory, anticancer etc. Some of these activities are involved in wound healing process, using the earthworm preparation. In some countries the earthworms are used as a part of healthy food. They have very high nutritive value because their bodies contain the high percentage of various proteins. Besides the human food, the earthworms are used in the feeding of animals (fish, chicken, etc..

  7. Accumulation of mercury and methylmercury by mushrooms and earthworms from forest soils

    Energy Technology Data Exchange (ETDEWEB)

    Rieder, Stephan R. [Rhizosphere Processes Group, Swiss Federal Research Institute WSL, 8903 Birmensdorf (Switzerland); Institute for Biogeochemistry and Pollutant Dynamics, ETH Zuerich, 8092 Zuerich (Switzerland); Brunner, Ivano [Rhizosphere Processes Group, Swiss Federal Research Institute WSL, 8903 Birmensdorf (Switzerland); Horvat, Milena [Jozef Stefan Institute, 1001 Ljubliana (Slovenia); Jacobs, Anna [Rhizosphere Processes Group, Swiss Federal Research Institute WSL, 8903 Birmensdorf (Switzerland); Department of Environmental Chemistry, University of Kassel, 37213 Witzenhausen (Germany); Frey, Beat, E-mail: beat.frey@wsl.ch [Rhizosphere Processes Group, Swiss Federal Research Institute WSL, 8903 Birmensdorf (Switzerland)

    2011-10-15

    Accumulation of total and methyl-Hg by mushrooms and earthworms was studied in thirty-four natural forest soils strongly varying in soil physico-chemical characteristics. Tissue Hg concentrations of both receptors did hardly correlate with Hg concentrations in soil. Both total and methyl-Hg concentrations in tissues were species-specific and dependent on the ecological groups of receptor. Methyl-Hg was low accounting for less than 5 and 8% of total Hg in tissues of mushrooms and earthworms, respectively, but with four times higher concentrations in earthworms than mushrooms. Total Hg concentrations in mushrooms averaged 0.96 mg Hg kg{sup -1} dw whereas litter decomposing mushrooms showed highest total Hg and methyl-Hg concentrations. Earthworms contained similar Hg concentrations (1.04 mg Hg kg{sup -1} dw) whereas endogeic earthworms accumulated highest amounts of Hg and methyl-Hg. - Highlights: > Hg and MeHg concentrations in mushrooms and earthworms at unpolluted forest soils. > Mushrooms and earthworms contained similar Hg concentrations. > MeHg was present in traces but four times higher in earthworms than in mushrooms. > Ecophysiological group influenced Hg and MeHg concentration in both receptors. - Accumulation of Hg and methyl-Hg by mushrooms and earthworms is species- and ecophysiological group dependent.

  8. Heavy Metal-Induced Oxidative DNA Damage in Earthworms: A Review

    OpenAIRE

    Kazuyoshi Tamae; Takeshi Hirano

    2010-01-01

    Earthworms can be used as a bio-indicator of metal contamination in soil, Earlier reports claimed the bioaccumulation of heavy metals in earthworm tissues, while the metal-induced mutagenicity reared in contaminated soils for long duration. But we examined the metal-induced mutagenicity in earthworms reared in metal containing culture beddings. In this experiment we observed the generation of 8-oxoguanine (8-oxo-Gua) in earthworms exposed to cadmium and nickel in soil. 8-oxo-Gua is a major pr...

  9. Accumulation of mercury and methylmercury by mushrooms and earthworms from forest soils

    International Nuclear Information System (INIS)

    Accumulation of total and methyl-Hg by mushrooms and earthworms was studied in thirty-four natural forest soils strongly varying in soil physico-chemical characteristics. Tissue Hg concentrations of both receptors did hardly correlate with Hg concentrations in soil. Both total and methyl-Hg concentrations in tissues were species-specific and dependent on the ecological groups of receptor. Methyl-Hg was low accounting for less than 5 and 8% of total Hg in tissues of mushrooms and earthworms, respectively, but with four times higher concentrations in earthworms than mushrooms. Total Hg concentrations in mushrooms averaged 0.96 mg Hg kg-1 dw whereas litter decomposing mushrooms showed highest total Hg and methyl-Hg concentrations. Earthworms contained similar Hg concentrations (1.04 mg Hg kg-1 dw) whereas endogeic earthworms accumulated highest amounts of Hg and methyl-Hg. - Highlights: ? Hg and MeHg concentrations in mushrooms and earthworms at unpolluted forest soils. ? Mushrooms and earthworms contained similar Hg concentrations. ? MeHg was present in traces but four times higher in earthworms than in mushrooms. ? Ecophysiological group influenced Hg and MeHg concentration in both receptors. - Accumulation of Hg and methyl-Hg by mushrooms and earthworms is species- and ecophysiological group dependent.

  10. Vermicomposting of Solid Waste Using Local and Exotic Earthworms: A Comparative Study.

    Science.gov (United States)

    Amit, Krishan; Ajit, Kumar; Arthanareeswari, M; Kamaraj, P

    2014-07-01

    The aim of this study was to assess the decomposition efficiency of earthworms, local (L.mauritii) as well as exotic (Eisenia foetida) in vermicomposting of garden litter in SRM University campus. The vermicompost produced through vermicomposting of garden litter mixed with cow dung in the ratio of 3:1 by using local and exotic earthworms (Eisenia foetida) was rich in ammoniacal nitrogen, nitrate nitrogen, available phosphorus, total potassium and TKN, and there was a reduction in total organic carbon and carbon to nitrogen ratio. The study reveals that the decomposition efficiency of exotic earthworms is better compared to local earthworms. PMID:26563089

  11. Bioaccumulation and enantioselectivity of type I and type II pyrethroid pesticides in earthworm.

    Science.gov (United States)

    Chang, Jing; Wang, Yinghuan; Wang, Huili; Li, Jianzhong; Xu, Peng

    2016-02-01

    In this study, the bioavailability and enantioselectivity differences between bifenthrin (BF, type?pyrethroid) and lambad-cyhalothrin (LCT, type ? pyrethroid) in earthworm (Eisenia fetida) were investigated. The bio-soil accumulation factors (BSAFs) of BF was about 4 times greater than that of LCT. LCT was degraded faster than BF in soil while eliminated lower in earthworm samples. Compound sorption plays an important role on bioavailability in earthworm, and the soil-adsorption coefficient (Koc) of BF and LCT were 22 442 and 42 578, respectively. Metabolic capacity of earthworm to LCT was further studied as no significant difference in the accumulation of LCT between the high and low dose experiment was found. 3-phenoxybenzoic acid (PBCOOH), a metabolite of LCT produced by earthworm was detected in soil. The concentration of PBCOOH at high dose exposure was about 4.7 times greater than that of in low dose level at the fifth day. The bioaccumulation of BF and LCT were both enantioselective in earthworm. The enantiomer factors of BF and LCT in earthworm were approximately 0.12 and 0.65, respectively. The more toxic enantiomers ((+)-BF and (-)-LCT) had a preferential degradation in earthworm and leaded to less toxicity on earthworm for racemate exposure. In combination with other studies, a liner relationship between Log BSAFS and Log Kow was observed, and the Log BSAFS decreased with the increase of Log Kow. PMID:26490429

  12. Status of chemical freeze-out

    International Nuclear Information System (INIS)

    The status of the energy dependence of the chemical freeze-out temperature and chemical potential obtained in heavy-ion collisions is presented. Recent proposals for chemical freeze-out conditions are compared

  13. Well-plate freeze-drying

    DEFF Research Database (Denmark)

    Trnka, Hjalte; Rantanen, Jukka; Grohganz, Holger

    2015-01-01

    Abstract Context: Freeze-drying in presence of excipients is a common practice to stabilize biomacromolecular formulations. The composition of this formulation is known to affect the quality of the final product. Objective: The aim of this study was to evaluate freeze-drying in well-plates as a high throughput platform for formulation screening of freeze-dried products. Methods: Model formulations consisting of mannitol, sucrose and bovine serum albumin were freeze-dried in brass well plates, pl...

  14. Effect of temperature and season on reproduction, neutral red retention and metallothionein responses of earthworms exposed to metals in field soils

    Energy Technology Data Exchange (ETDEWEB)

    Svendsen, Claus [Centre for Ecology and Hydrology, Monks Wood, Abbots Ripton, Huntingdon, Cambridgeshire PE28 2LS (United Kingdom)]. E-mail: csv@ceh.ac.uk; Hankard, Peter K. [Centre for Ecology and Hydrology, Monks Wood, Abbots Ripton, Huntingdon, Cambridgeshire PE28 2LS (United Kingdom)]. E-mail: pkh@ceh.ac.uk; Lister, Lindsay J. [Centre for Ecology and Hydrology, Monks Wood, Abbots Ripton, Huntingdon, Cambridgeshire PE28 2LS (United Kingdom)]. E-mail: llist@ceh.ac.uk; Fishwick, Samantha K. [Environment Agency, Block 1 Government Buildings, Burghill Road, Westbury-on-Trym, Bristol BS10 6BF (United Kingdom)]. E-mail: samantha.fishwick@environment-agency.gov.uk; Jonker, Martijs J. [Centre for Ecology and Hydrology, Monks Wood, Abbots Ripton, Huntingdon, Cambridgeshire PE28 2LS (United Kingdom)]. E-mail: mjonker@science.uva.nl; Spurgeon, David J. [Centre for Ecology and Hydrology, Monks Wood, Abbots Ripton, Huntingdon, Cambridgeshire PE28 2LS (United Kingdom)]. E-mail: dasp@ceh.ac.uk

    2007-05-15

    This study investigated the short-term survival, reproduction and physiological (lysosomal membrane stability, metallothionein transcript copy number, body tissue metal concentrations) responses of Lumbricus rubellus exposed to metal contaminated field soils under different laboratory temperatures (10, 15 and 20 {sup o}C) and physiological responses of earthworms collected from the field in three different seasons (spring, autumn, winter). In the laboratory, metal contaminated soils had significant effects on reproduction (p < 0.001), metallothionein-2 (MT-2) expression (p = 0.033) and earthworm As (p = 0.003), Cd (p = 0.001), Pb (p < 0.001) and Zn (p < 0.001) concentration, but not lysosomal membrane stability and tissue Hg and Cu. No effect of temperature was found for any parameter. Principal component analysis of extractable and tissue metal concentrations indicated PC1 as a measure of metal stress. Both cocoon production (r = - 0.75) and MT-2 induction (r = 0.41) were correlated with PC1. A correlation was also found between cocoon production and MT-2 expression (r = - 0.41). Neutral red retention and MT-2 measurements in worms collected from the field sites in three seasons confirmed the absence of a temperature effect on these responses. - Laboratory and field studies demonstrate metal effects on earthworm life-cycle and biochemical responses are not influenced by temperature regime.

  15. Effect of temperature and season on reproduction, neutral red retention and metallothionein responses of earthworms exposed to metals in field soils

    International Nuclear Information System (INIS)

    This study investigated the short-term survival, reproduction and physiological (lysosomal membrane stability, metallothionein transcript copy number, body tissue metal concentrations) responses of Lumbricus rubellus exposed to metal contaminated field soils under different laboratory temperatures (10, 15 and 20 oC) and physiological responses of earthworms collected from the field in three different seasons (spring, autumn, winter). In the laboratory, metal contaminated soils had significant effects on reproduction (p < 0.001), metallothionein-2 (MT-2) expression (p = 0.033) and earthworm As (p = 0.003), Cd (p = 0.001), Pb (p < 0.001) and Zn (p < 0.001) concentration, but not lysosomal membrane stability and tissue Hg and Cu. No effect of temperature was found for any parameter. Principal component analysis of extractable and tissue metal concentrations indicated PC1 as a measure of metal stress. Both cocoon production (r = - 0.75) and MT-2 induction (r = 0.41) were correlated with PC1. A correlation was also found between cocoon production and MT-2 expression (r = - 0.41). Neutral red retention and MT-2 measurements in worms collected from the field sites in three seasons confirmed the absence of a temperature effect on these responses. - Laboratory and field studies demonstrate metal effects on earthworm life-cycle and biochemical responses are not influenced by temperature regime

  16. The relationship of freeze tolerance with intracellular compounds in baker's yeasts.

    Science.gov (United States)

    Shi, Xiaojian; Miao, Yelian; Chen, Jie Yu; Chen, Jun; Li, Wenli; He, Xun; Wang, Jining

    2014-03-01

    Freeze-tolerant baker's yeasts are required for the processing of frozen doughs. The present study was carried out to investigate the cell survival rate after frozen storage and the change of fermentability in dough due to frozen storage, and to discuss quantitatively the relationship of freeze tolerance with intracellular trehalose, amino acids, and glycerol, using six types of baker's yeasts as the test materials. The experimental results showed that the fermentability of yeast cells in frozen dough was strongly correlated with the cell survival rate. The baker's yeast with a higher level of cell survival rate had a larger increase in the total intracellular compound content after frozen storage, and the cell survival rate increased linearly with increasing total intracellular compound content in frozen yeast cells. Trehalose was a primary compound affecting freeze tolerance, followed by glutamic acid, arginine, proline, asparagic acid, and glycerol. The basic information provided by the present study is useful for exploring the freeze-tolerance mechanisms of baker's yeast cells, breeding better freeze-tolerant baker's yeast strains, and developing more effective cryoprotectants. PMID:24482281

  17. Conditions driving chemical freeze-out

    OpenAIRE

    Tawfik, A

    2004-01-01

    We propose the entropy density as the thermodynamic condition driving best the chemical freeze-out in heavy-ion collisions. Taking its value from lattice calculations at zero chemical potential, we find that it is excellent in reproducing the experimentally estimated freeze-out parameters. The two characteristic endpoints in the freeze-out diagram are reproduced as well.

  18. Using Flow Cytometry to Measure Phagocytic Uptake in Earthworms

    Directory of Open Access Journals (Sweden)

    Sheryl L. Fuller-Espie

    2010-10-01

    Full Text Available 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.

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

    Science.gov (United States)

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

    2014-01-01

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

  20. Invasive and exotic earthworms: an unaccounted change to mercury cycling in northeastern US forest soils

    Science.gov (United States)

    Richardson, J. B.; Friedland, A. J.; Grres, J. H.; Renock, D. J.; Jackson, B. P.

    2014-12-01

    Invasive and exotic earthworms are now present in many forested areas of the northeastern US with currently unquantified consequences to abiotic and biotic Hg cycling. To quantify these effects, we measured Hg concentrations (mg kg-1) and amounts (?g m-2) in earthworms and soil horizons at 45 soil pits from 9 sites in northern New England. Seven earthworm species were observed in varying assemblages. Most earthworm species attained concentrations of Hg potentially hazardous to wildlife that may ingest them, with highest concentrations found in shallow-burrowing, litter-feeders. Specifically, Aporrectodea rosea and Amynthas agrestis had the greatest Hg concentrations (0.9 0.1) and Hg amounts (8 2) ?g m-2. Aporrectodea rosea and Amynthas agrestis were found to inhabit the forest floor and the top 5 cm of the mineral horizons in high abundance, potentially making it a readily accessible prey species. Bioaccumulation of Hg by invasive and exotic earthworms may be an important mechanism that transfers Hg to ground foraging predators, such as thrushes, red-backed salamanders and foxes, which is generally unaccounted for in terrestrial food chains. Earthworm Hg concentrations were poorly correlated with their respective soil Hg concentrations, suggesting a species dependence for Hg bioaccumulation rather than site effects. We observed that forest floor Hg concentrations and amounts were 23% and 57% lower, respectively, at soil pits with earthworms compared to those without. Moreover, Hg amounts in forest floor-feeding earthworms exceeded the remaining forest floor Hg pools. Mercury concentrations and pools in the mineral soil were 21% and 33% lower, respectively, for soil pits with earthworms compared to those without. We hypothesize that enhanced decomposition, horizon disturbance and bioaccumulation by earthworms has decreased Hg amounts in the forest floor and mineral soil. Our results suggest that earthworms are decreasing Hg storage in forest soils with potential hazardous impacts for predatory animals in northeastern US forests and other ecosystems.

  1. Earthworms in an arable field-forest ecotone.

    Czech Academy of Sciences Publication Activity Database

    Pil, Vclav; Zeithaml, J.

    ?esk Bud?jovice : Institute of Soil Biology ASCR, 2005, s. 113-117. ISBN 80-86525-04-X. [Contributions to soil Zoology in Central Europe I. Central European Workshop on Soil Zoology /7./. ?esk Bud?jovice (CZ), 14.04.2003-16.04.2003] Institutional research plan: CEZ:AV0Z6066911 Keywords : earthworms * ecotone * edge effect Subject RIV: EH - Ecology, Behaviour

  2. The ecology and control of earthworms on golf courses

    OpenAIRE

    Bartlett, Mark D.

    2006-01-01

    Earthworm casts on golf courses affect the playability of the turf and can potentially damage mowing equipment. Traditionally this problem has been limited using chemical controls. It is estimated that 0.6% of the total UK land surface is occupied by golf courses, therefore, the land management strategies which green keepers adopt with respect to the application of chemicals has a major environmental impact. The aim of this thesis was to investigate the ecology and potential co...

  3. Unearthing the genome of the earthworm Lumbricus rubellus

    OpenAIRE

    Elsworth, Benjamin Lloyd

    2013-01-01

    The earthworm has long been of interest to biologists, most notably Charles Darwin, who was the first to reveal their true role as eco-engineers of the soil. However, to fully understand an animal one needs to combine observational data with the fundamental building blocks of life, DNA. For many years, sequencing a genome was an incredibly costly and time-consuming process. Recent advances in sequencing technology have led to high quality, high throughput data being available a...

  4. Colonization of PAH-contaminated dredged sediment by earthworms

    OpenAIRE

    Eijsackers, H; Bruggeman, J.; Harmsen, J.; Kort, T., de; Schakel, A.

    2009-01-01

    In freshly deposited dredged sediment contaminated with PAHs, we followed the colonization of earthworm species by monthly monitoring over two years. Already five months after deposition the first species, Lumbricus castaneus, appeared, although only temporarily. The first permanent colonizing species was L. rubellus, soon followed by Aporrectodea caliginosa and L. castaneus, and a few months later Eiseniella tetraeda. At the end of the two-year observation period some first few specimen of A...

  5. Second contribution to the knowledge of earthworms (Lumbricidae) in Montenegro

    OpenAIRE

    Stojanovi? Mirjana M.; Karaman Spasenija D.

    2003-01-01

    This paper contains the results of qualitative analysis of Lumbricidae (Oligochaeta) in Montenegro, during the period 1997-2003. The research has included natural and cultivated biotopes. The presence of 15 species was established and the habitats, localities and their zoogeographical position are given. In Montenegro we found four species for the first time Dendrobaena jastrebensis, D. vejdovskyi, Octodrilus bretcheri and Lumbricus terrestris. The complete list of earthworm species in Monten...

  6. Effects of low voltage electrolysis and freezing on coliform content of contaminated water

    International Nuclear Information System (INIS)

    A sewage sample was mixed with drinking water and subjected to low voltage (15V) electrolysis in the presence of 1% NaCl. The prepared sample was also kept in freezer with and without the presence of sodium chloride for 4-hours. Among these treatments the electrolysis proved to kill the coliforms, while the freezing reduced the bacterial content. Antibiotics sensitivity patterns revealed that certain of the coliform strains survived the freezing and thawing shocks. Nature of such surviving bacteria and need to study chemical parameters of electrolyzed water are discussed. (author)

  7. Earthworms as agents for ecotoxicity in roxarsone-contaminated soil ecosystem: a modeling study of ultrastructure and proteomics.

    Science.gov (United States)

    Guo, Ruizi; Ding, Xueyao; Xiong, Wenguang; Zhong, Xiaoxia; Liang, Wenfei; Gao, Shangji; Hong, Mei; Sun, Yongxue

    2015-08-01

    Contamination of roxarsone has been recognized as a potential environmental hazard. In this study, Eisenia fetida samples were collected after roxarsone exposures to analyze their intestinal epithelium ultrastructure, expression levels of stress-related genes, and proteomics. Our results showed that mitochondria and endoplasmic reticulum in roxarsone-treated earthworms demonstrated variety of damages. Furthermore, 149 proteins were displayed in 2-DE, and 36 of them were identified by MALDI-TOF/TOF-MS. Those identified proteins are involved in several important processes including cell immunity, cell stress responses, and cell genetic behaviors. Our study demonstrates the toxicity responses of earthworms toward arsenic-based animal drug roxarsone with practical usefulness and demonstrates a proteomic profile change that may be critical for the roxarsone stress survival mechanisms of E. fetida. Graphical Abstract Inspiration of this referred to the form of Fig. 4 in the article "Proteomic analysis of a high aluminum tolerant yeast Rhodotorula taiwanensis RS1 in response to aluminum stress" of Chao, W et al. PMID:25903172

  8. The Earthworm Eisenia fetida Can Help Desalinate a Coastal Saline Soil in Tianjin, North China

    Science.gov (United States)

    Zhang, Tao; Li, Suyan; Sun, Xiangyang; Zhang, Yang; Gong, Xiaoqiang; Fu, Ying; Jia, Liming

    2015-01-01

    A laboratory microcosm experiment was conducted to determine whether the earthworm Eisenia fetida could survive in a saline soil from a field site in North China, and an experiment using response surface methodology was conducted at that field site to quantify the effects of E. fetida and green waste compost (GWC) on the salt content of the soil. The microcosm results showed that E. fetida survived in GWC-amended saline soil and increased the contents of humic acid, available N, and available P in the GWC-amended soil. The data from the field experiment were described by the following second-order model:y^=-1.76+0.091x1+0.48x2-0.00083x1x2-0.00078x12-0.022x22, where y is the decrease in soil salinity (g of salt per kg of dry soil) relative to the untreated control, x1 is the number of E. fetida added per m2, and x2 is the quantity of GWC added in kg per m2. The model predicted that the total salt content of the saline soil would decrease by > 2 g kg-1 (p<0.05) when 2990 individuals m-2 of E. fetida and 6.115.0 kg m-2 of GWC were applied. We conclude that the use of E. fetida for soil desalination is promising and warrants additional investigation. PMID:26699869

  9. Modeling of the accumulation of organic lipophilic chemicals in earthworms

    Energy Technology Data Exchange (ETDEWEB)

    Belfroid, A.; Seinen, W.; Leeuwen, K. van; Hermens, J. [Univ. of Utrecht (Netherlands). Research Inst. of Toxicology; Gestel, K. van [Vrije Univ. (Netherlands). Dept. of Ecology and Ecotoxicology

    1994-12-31

    For aquatic and terrestrial species living in contaminated sediments and soils it is assumed that the major route of uptake of organic lipophilic compounds is by passive diffusion of the compound dissolved in the interstitial water. Dietary uptake will only be important for extremely lipophilic compounds with log K{sub ow} larger than 5--6. An accumulation study with earthworms in OECD artificial soil confirmed this hypothesis. However, the authors also observed dietary uptake in earthworms after feeding them with food contaminated with three chlorobenzenes, PCB153 and octachloronaphthalene. Still, the question remained whether dietary uptake is an important route of exposure. Therefore, a model was developed that, unlike for example the equilibrium partition theory, incorporates two routes of uptake. The model can be used to estimate the accumulation of inert organic chemicals with log Kow 2--7 in earthworms, but also to determine the relative contribution of the two routes of uptake to the total body burden. It will be shown that the relative contribution depends on the lipophilicity of the compound and also on the type of soil.

  10. PREDICTION OF BIOAVAILABILITY OF CHLORPYRIFOS RESIDUES IN SOIL TO EARTHWORMS

    Scientific Electronic Library Online (English)

    X.M, Wu; Y.L, Yu; M, Li; Y.H, Long; H, Fang; S.N, Li.

    Full Text Available An incubation test was conducted to investigate the effect of aging on bioavailability of chlorpyrifos in soil and to assess the feasibility of chemical extraction techniques for predicting bioavailability of chlorpyrifos in soil. Chlorpyrifos was spiked into sterilized soil and aged in microcosms f [...] or up to 120 days. The earthworms were incubated in the spiked soils, at 0, 7, 14, 30, 60, and 120 days after spiking, for a period of 7 days. After exposure, chlorpyrifos concentrations in the earthworm tissues were determined. Change in chemical extractability of soil-chlorpyrifos was measured using a several solvent systems including methanol, methanol-water (9:1), acetone-water (5:3), and water. The results show that chemical extractability and earthworm bioavailability of chlorpyrifos in soil decreased with aging. The amount of aged and unaged chlorpyrifos recovered from soil varied with the individual chemical extractant and extraction method. Concentrations of chlorpyrifos in Eisenia foetida were significantly higher than in Allolobophora caliginosa, suggesting that the bioavailability of chlorpyrifos was a species-dependent process. The extractability of chlorpyrifos by chemical solvents was significantly correlated with bioavailability fraction of E. foetida and A. caliginosa, showing that these extraction techniques may be efficient for predicting bioavailability of chlorpyrifos in soil.

  11. Comparative Genomics of Symbiotic Bacteria in Earthworm Nephridia

    DEFF Research Database (Denmark)

    Kjeldsen, Kasper Urup; Pinel, Nicolas

    The excretory and osmoregulatory organs (nephridia) of lumbricid earthworms are densely colonized by extracellular bacterial symbionts belonging to the newly established betaproteobacterial genus Verminephrobacter. The nephridial symbiont of the earthworm Eisenia fetida was subjected to full genome sequencing along with two of its closest relatives; the plant pathogenic Acidovorax avena subsp. citrulli and the free-living Acidovorax sp. JS42. In addition, the genome of the nephridial symbiont of the earthworm Aporrectodea tuberculata was partially sequenced. In order to resolve the functional and evolutionary basis of the symbiosis we annotated and compared the genomes. The genomes ranged in size from 4.4 to 5.6 Mbp, the E. fetida symbiont genome being the largest. The symbiont genomes showed no evidence of gene-loss related to any particular type of functional gene category. In contrast, genes predicted to be involved in transport processes were highly overrepresented in the symbiont genomes due to massive paralogous expansion of genes encoding ABC-type amino acid and peptide uptake systems. Thus, symbionts seem well-adapted to the nephridial environment being able to profit from proteinaceous excretion products. Gene order was highly conserved between the genomes of Acidovorax avena and Acidovorax sp. JS42, whereas the E. fetida symbiont genome held very little conservation of gene order compared to either of the latter two. Repetitive sequences were excessively abundant throughout the genomes of both symbionts. Together, this is indicative of high recombinatorial frequency in the symbiont genomes the function of which is presently poorly understood.

  12. PREDICTION OF BIOAVAILABILITY OF CHLORPYRIFOS RESIDUES IN SOIL TO EARTHWORMS

    Directory of Open Access Journals (Sweden)

    X.M Wu

    2011-01-01

    Full Text Available An incubation test was conducted to investigate the effect of aging on bioavailability of chlorpyrifos in soil and to assess the feasibility of chemical extraction techniques for predicting bioavailability of chlorpyrifos in soil. Chlorpyrifos was spiked into sterilized soil and aged in microcosms for up to 120 days. The earthworms were incubated in the spiked soils, at 0, 7, 14, 30, 60, and 120 days after spiking, for a period of 7 days. After exposure, chlorpyrifos concentrations in the earthworm tissues were determined. Change in chemical extractability of soil-chlorpyrifos was measured using a several solvent systems including methanol, methanol-water (9:1, acetone-water (5:3, and water. The results show that chemical extractability and earthworm bioavailability of chlorpyrifos in soil decreased with aging. The amount of aged and unaged chlorpyrifos recovered from soil varied with the individual chemical extractant and extraction method. Concentrations of chlorpyrifos in Eisenia foetida were significantly higher than in Allolobophora caliginosa, suggesting that the bioavailability of chlorpyrifos was a species-dependent process. The extractability of chlorpyrifos by chemical solvents was significantly correlated with bioavailability fraction of E. foetida and A. caliginosa, showing that these extraction techniques may be efficient for predicting bioavailability of chlorpyrifos in soil.

  13. Freeze Technology for Nuclear Applications - 13590

    International Nuclear Information System (INIS)

    Freezing of soil materials is a complicated process of a number of physical processes: - freezing of pore water in a thermal gradient, - cryogenic suction causing water migration and - ice formation expanding pores inducing frost heave. Structural changes due to increase of effective stress during freezing also take place. The over consolidation gives a powerful dewatering/drying effect and the freeze process causes separation of contaminates. Artificial ground freezing (AGF is a well established technique first practiced in south Wales, as early as 1862. AGF is mostly used to stabilize tunnels and excavations. During the last ten years underwater applications of freeze technologies based on the AGF have been explored in Sweden. The technology can, and has been, used in many different steps in a remediation action. Freeze Sampling where undisturbed samples are removed in both soft and hard sediment/sludge, Freeze Dredging; retrieval of sediment with good precision and minimal redistribution, and Freeze Drying; volume reduction of contaminated sludge/sediment. The application of these technologies in a nuclear or radioactive environment provides several advantages. Sampling by freezing gives for example an advantage of an undisturbed sample taken at a specified depth, salvaging objects by freezing or removal of sludges is other applications of this, for the nuclear industry, novel technology. (authors)

  14. Freeze Technology for Nuclear Applications - 13590

    Energy Technology Data Exchange (ETDEWEB)

    Rostmark, Susanne C.; Knutsson, Sven [Lulea University of Technology (Sweden); Lindberg, Maria [Studsvik Nuclear AB, 611 82 Nykoeping (Sweden)

    2013-07-01

    Freezing of soil materials is a complicated process of a number of physical processes: - freezing of pore water in a thermal gradient, - cryogenic suction causing water migration and - ice formation expanding pores inducing frost heave. Structural changes due to increase of effective stress during freezing also take place. The over consolidation gives a powerful dewatering/drying effect and the freeze process causes separation of contaminates. Artificial ground freezing (AGF is a well established technique first practiced in south Wales, as early as 1862. AGF is mostly used to stabilize tunnels and excavations. During the last ten years underwater applications of freeze technologies based on the AGF have been explored in Sweden. The technology can, and has been, used in many different steps in a remediation action. Freeze Sampling where undisturbed samples are removed in both soft and hard sediment/sludge, Freeze Dredging; retrieval of sediment with good precision and minimal redistribution, and Freeze Drying; volume reduction of contaminated sludge/sediment. The application of these technologies in a nuclear or radioactive environment provides several advantages. Sampling by freezing gives for example an advantage of an undisturbed sample taken at a specified depth, salvaging objects by freezing or removal of sludges is other applications of this, for the nuclear industry, novel technology. (authors)

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

    Scientific Electronic Library Online (English)

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

    2006-03-01

    Full Text Available Earthworms are soil invertebrates that play a key role in recycling organic matter in soils.In Nigeria, earthworms include Libyodrillus violaceous. Aerobic and anaerobic bacterial counts, as well as fungal counts of viable microorganisms in soils and gut sections, were made on twenty L. violaceous c [...] ollected from different sites on the campus of the University of Agriculture, Abeokuta, Nigeria. The samples were collected between April and November, 2002. Numbers of microorganisms were higher in castings and gut sections than in uningested soil samples. The guts and their contents also had higher moisture and total nitrogen contents than the uningested soils. Bacteria and fungi isolated from the samples were identified by standard microbiological procedures on the bases of their morphological and biochemical characteristics. Isolated bacteria were identified as Staphylococcus, Bacillus spp., Pseudomonas aeruginosa, Streptococcus mutans, Clostridium, Spirocheata spp., Azotobacter spp., Micrococcus lylae, Acinetobacter spp., Halobacterium for bacteria. Yeast isolates were identified as Candida spp., Zygosaccharomyces spp., Pichia spp., and Saccharomyces spp while molds were identified as, Aspergillus spp., Pytium spp., Penicillium spp., Fusarium spp and Rhizopus spp. Of the five locations examined, the refuse dump area had the highest numbers of both aerobic and anaerobic organisms, followed by the arboretum while the cultivated land area recorded the lowest counts. The higher numbers of microorganisms observed in the gut sections and casts of the earthworms examined in this work reinforce the general concept that the gut and casts of earthworms show higher microbial diversity and activity than the surrounding soil. Rev. Biol. Trop. 54 (1): 49-58. Epub 2006 Mar 31.

  16. Temperature-dependent alterations in metabolic enzymes and proteins of three ecophysiologically different species of earthworms

    Scientific Electronic Library Online (English)

    G, Tripathi; N., Kachhwaha; I., Dabi; N., Bandooni.

    2011-08-01

    Full Text Available The effects of varying temperatures (12 - 44 C) on the specific activity of cytoplasmic malate dehydrogenase ((cMDH), mitochondrial malate dehydrogenase (mMDH) and lactate dehydrogenase (LDH) of some earthworms (Metaphire posthuma, Perionyx sansibaricus and Lampito mauritii) were studied. The effec [...] ts of different temperatures on supernatant and mitochondrial protein contents were also investigated. The specific activities of cMDH, mMDH and LDH of the earthworms decreased gradually as a function of increasing temperature from 12 to 44C. Higher metabolic energy was needed to maintain the activity at low temperatures. Hence, the earthworms showed increased enzyme specific activity at low temperatures. However, the protein content increased upto 28C. Afterwards, with the increase in the temperature from 28 to 42C, the proteins in the earthworms showed a significant decrease. The temperature-associated changes in the protein content could be explained by the fact that protein synthesizing capacity was hampered above and below the optimum temperature range. The most pronounced effects of varying temperatures were on P. sansibaricus. It might be due to the epigeic nature of the earthworm species. Then minimum effect was on the endogeic earthworm M. posthuma. Virtually, the differences in the enzymes physiology were associated with the differences in the ecological categories of the earthworms. This clearly demonstrate a possible link between the physiology and ecology at aerobic (cMDH, mMDH) and anaerobic (LDH) levels in the tropical earthworms.

  17. Effects of treatment with sodium fluoride and subsequent starvation on fluoride content of earthworms

    Energy Technology Data Exchange (ETDEWEB)

    Walton, K.C.

    1987-01-01

    The two experiments described here originated during a long-term investigation into the occurrence and movement of pollutant fluoride in a terrestrial ecosystem. Moles (Talpa europaea) whose diet consist largely of various species of earthworm Lumbricidae, are one of the species under investigation. Bone fluoride in moles was found to be higher, on average, than in foxes or small rodents. Moles probably acquire fluoride from their earthworm diet. Earthworms do not have any readily identifiable tissue in which to store large amounts of fluoride but, for their size, they have a considerable amount of soil in their gut, up oto 20% of their dry weight. Preliminary measurements of fluoride in whole earthworms suggested that observed levels could probably be accounted for by fluoride bound in the mineral part of contained soil and released during preparatory ashing. Two experiments to investigate this situation are described; here their aims were: to expose earthworms kept in soil to different concentrations of sodium fluoride; to measure resulting fluoride in earthworms when soil was removed from their gut by starvation for varying periods of time; and to compare amounts of fluoride in whole starved earthworms with those in starved earthworms from which remaining soil had also been physically removed by dissection and washing.

  18. Temperature-dependent alterations in metabolic enzymes and proteins of three ecophysiologically different species of earthworms

    Directory of Open Access Journals (Sweden)

    G Tripathi

    2011-08-01

    Full Text Available The effects of varying temperatures (12 - 44 C on the specific activity of cytoplasmic malate dehydrogenase ((cMDH, mitochondrial malate dehydrogenase (mMDH and lactate dehydrogenase (LDH of some earthworms (Metaphire posthuma, Perionyx sansibaricus and Lampito mauritii were studied. The effects of different temperatures on supernatant and mitochondrial protein contents were also investigated. The specific activities of cMDH, mMDH and LDH of the earthworms decreased gradually as a function of increasing temperature from 12 to 44C. Higher metabolic energy was needed to maintain the activity at low temperatures. Hence, the earthworms showed increased enzyme specific activity at low temperatures. However, the protein content increased upto 28C. Afterwards, with the increase in the temperature from 28 to 42C, the proteins in the earthworms showed a significant decrease. The temperature-associated changes in the protein content could be explained by the fact that protein synthesizing capacity was hampered above and below the optimum temperature range. The most pronounced effects of varying temperatures were on P. sansibaricus. It might be due to the epigeic nature of the earthworm species. Then minimum effect was on the endogeic earthworm M. posthuma. Virtually, the differences in the enzymes physiology were associated with the differences in the ecological categories of the earthworms. This clearly demonstrate a possible link between the physiology and ecology at aerobic (cMDH, mMDH and anaerobic (LDH levels in the tropical earthworms.

  19. Microbial communities associated with three populations of Eisenia earthworms - polyphasic approach.

    Czech Academy of Sciences Publication Activity Database

    Koubov, Anna; Pil, Vclav; Chro?kov, Alica; Elhottov, Dana

    Xalapa : Instituto de Ecologa, A.C, 2010. s. 189. [International Symposium on Earthworm Ecology /9./. 05.09.2010-10.09.2010, Xalapa] Institutional research plan: CEZ:AV0Z60660521 Keywords : microbial communities * Eisenia earthworms * polyphasic approach Subject RIV: EH - Ecology, Behaviour

  20. The effect of earthworms on accumulation of soil organic matter during post mining soil development.

    Czech Academy of Sciences Publication Activity Database

    Frouz, Jan; Pil, Vclav

    Krakw : Jagellonian University, 2006. s. 176. [International Symposium on Earthworm Ecology /8./. 04.09.2006-09.09.2006, Krakw] R&D Projects: GA AV ?R(CZ) 1QS600660505 Institutional research plan: CEZ:AV0Z60660521 Keywords : earthworms * accumulation of soil organic matter * post mining soil development Subject RIV: EH - Ecology, Behaviour

  1. The effects of production systems on earthworm assemblages in vineyards and apple orchards.

    Czech Academy of Sciences Publication Activity Database

    Pil, Vclav

    Xalapa : Instituto de Ecologa, A.C, 2010. s. 114. [International Symposium on Earthworm Ecology /9./. 05.09.2010-10.09.2010, Xalapa] Institutional research plan: CEZ:AV0Z60660521 Keywords : earthworm assemblages * vineyards * apple orchards Subject RIV: EH - Ecology, Behaviour

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

    Energy Technology Data Exchange (ETDEWEB)

    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

    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.

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

    Science.gov (United States)

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

    2014-01-01

    The earthworm is ideal for studying action potential conduction velocity in a classroom setting, as its simple linear anatomy allows easy axon length measurements and the worm's sparse coding allows single action potentials to be easily identified. The earthworm has two giant fiber systems (lateral and medial) with different conduction

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

    Science.gov (United States)

    Liu, Xiaoli; Hu, Chengxiao; Zhang, Shuzhen

    2005-08-01

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

  5. Influence of earthworm mucus and amino acids on tomato seedling growth and cadmium accumulation

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Shujie [College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Hu Feng, E-mail: fenghu@njau.edu.c [College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Li Huixin; Li Xiuqiang [College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China)

    2009-10-15

    The effects on the growth of tomato seedlings and cadmium accumulation of earthworm mucus and a solution of amino acids matching those in earthworm mucus was studied through a hydroponic experiment. The experiment included four treatments: 5 mg Cd L{sup -1} (CC), 5 mg Cd L{sup -1} + 100 mL L{sup -1} earthworm mucus (CE), 5 mg Cd L{sup -1} + 100 mL L{sup -1} amino acids solution (CA) and the control (CK). Results showed that, compared with CC treatment, either earthworm mucus or amino acids significantly increased tomato seedling growth and Cd accumulation but the increase was much higher in the CE treatment compared with the CA treatment. This may be due to earthworm mucus and amino acids significantly increasing the chlorophyll content, antioxidative enzyme activities, and essential microelement uptake and transport in the tomato seedlings. The much greater increase in the effect of earthworm mucus compared with amino acid treatments may be due to IAA-like substances in earthworm mucus. - Earthworm mucus increased tomato seedlings growth and Cd accumulation through increasing chlorophyll content, antioxidative enzyme activities, and essential microelement accumulation.

  6. THE RELATIONSHIP BETWEEN MASS OF NEWLY HATCHED INDIVIDUALS AND COCOON MASS IN LUMBRICID EARTHWORMS

    DEFF Research Database (Denmark)

    Bruus, Marianne; Bjerre, Arne

    1991-01-01

    Earthworm cocoons from laboratory cultures were collected and their mass was determined. When hatched, the mass of the young worms was found. Cocoon mass and the mass of hatchlings varied considerably within species. The hygromass of newly hatched earthworms was found to correlate linearly with cocoon hygromass. It is concluded that cocoon hygromass may offer a prediction for hygromass of hatchlings.

  7. Mercury, cadmium and lead concentrations in different ecophysiological groups of earthworms in forest soils

    International Nuclear Information System (INIS)

    Bioaccumulation of Hg, Cd and Pb by eight ecophysiologically distinct earthworm species was studied in 27 polluted and uncontaminated forest soils. Lowest tissue concentrations of Hg and Cd occurred in epigeic Lumbricus rubellus and highest in endogeic Octolasion cyaneum. Soils dominated by Dendrodrilus rubidus possess a high potential of risk of Pb biomagnification for secondary predators. Bioconcentration factors (soil-earthworm) followed the sequence ranked Cd > Hg > Pb. Ordination plots of redundancy analysis were used to compare HM concentrations in earthworm tissues with soil, leaf litter and root concentrations and with soil pH and CEC. Different ecological categories of earthworms are exposed to Hg, Cd and Pb in the topsoil by atmospheric deposition and accumulate them in their bodies. Species differences in HM concentrations largely reflect differences in food selectivity and niche separation. - Accumulation of non-essential heavy metals by earthworms is species-dependent and is affected by soil characteristics in natural forest soils

  8. Mercury, cadmium and lead concentrations in different ecophysiological groups of earthworms in forest soils

    Energy Technology Data Exchange (ETDEWEB)

    Ernst, Gregor; Zimmermann, Stefan [Soil Sciences, Swiss Federal Research Institute WSL, Zuercherstrasse 111, CH-8903 Birmensdorf (Switzerland); Christie, Peter [Agricultural and Environmental Science Department, Queen' s University Belfast, Newforge Lane, Belfast BT9 5PX (United Kingdom); Frey, Beat [Soil Sciences, Swiss Federal Research Institute WSL, Zuercherstrasse 111, CH-8903 Birmensdorf (Switzerland)], E-mail: beat.frey@wsl.ch

    2008-12-15

    Bioaccumulation of Hg, Cd and Pb by eight ecophysiologically distinct earthworm species was studied in 27 polluted and uncontaminated forest soils. Lowest tissue concentrations of Hg and Cd occurred in epigeic Lumbricus rubellus and highest in endogeic Octolasion cyaneum. Soils dominated by Dendrodrilus rubidus possess a high potential of risk of Pb biomagnification for secondary predators. Bioconcentration factors (soil-earthworm) followed the sequence ranked Cd > Hg > Pb. Ordination plots of redundancy analysis were used to compare HM concentrations in earthworm tissues with soil, leaf litter and root concentrations and with soil pH and CEC. Different ecological categories of earthworms are exposed to Hg, Cd and Pb in the topsoil by atmospheric deposition and accumulate them in their bodies. Species differences in HM concentrations largely reflect differences in food selectivity and niche separation. - Accumulation of non-essential heavy metals by earthworms is species-dependent and is affected by soil characteristics in natural forest soils.

  9. Metal content of earthworms in sludge-amended soils: uptake and loss

    Energy Technology Data Exchange (ETDEWEB)

    Neuhauser, E.F.; Malecki, M.R.; Cukic, Z.V.

    1985-11-01

    The widespread practice of landspreading of sludge has raised concern about increasing concentrations of potentially toxic metals in soils, with the possibility of these metals adversely impacting terrestrial and aquatic ecosystems. Earthworms, as one of the largest components of the soil biota, are useful indicators of potentially toxic soil metal concentrations. The study describes the metal content of five metals (Cd, Cu, Ni, Pb, and Zn) in one earthworm species, Allolobophora tuberculata, as a function of varying soil metal concentrations in the same soil type and the ability of the earthworms to bioconcentrate the five metals. The rate of uptake of the five metals in earthworms with initially low concentrations of metals placed in a soil with high metal concentrations was evaluated for a 112 day period. The rate of loss of the five metals in earthworms with initially high metal concentrations placed in soil with low metal concentrations was also examined.

  10. Earthworms modify microbial community structure and accelerate maize stover decomposition during vermicomposting.

    Science.gov (United States)

    Chen, Yuxiang; Zhang, Yufen; Zhang, Quanguo; Xu, Lixin; Li, Ran; Luo, Xiaopei; Zhang, Xin; Tong, Jin

    2015-11-01

    In the present study, maize stover was vermicomposted with the epigeic earthworm Eisenia fetida. The results showed that, during vermicomposting process, the earthworms promoted decomposition of maize stover. Analysis of microbial communities of the vermicompost by high-throughput pyrosequencing showed more complex bacterial community structure in the substrate treated by the earthworms than that in the control group. The dominant microbial genera in the treatment with the earthworms were Pseudoxanthomonas, Pseudomonas, Arthrobacter, Streptomyces, Cryptococcus, Guehomyces, and Mucor. Compared to the control group, the relative abundance of lignocellulose degradation microorganisms increased. The results indicated that the earthworms modified the structure of microbial communities during vermicomposting process, activated the growth of lignocellulose degradation microorganisms, and triggered the lignocellulose decomposition. PMID:26139410

  11. Microflora dynamics in earthworms casts in an artificial soil (biosynthesol containing lactic acid oligomers

    Directory of Open Access Journals (Sweden)

    Alauzet Nathalie

    2001-01-01

    Full Text Available Studies were performed to appreciate the presence of micro-organisms able to degrade OLA, in earthworms casts or in the surroundings. Worms were grown in biosynthesol, an artificial soil. The counting of bacteria and fungi in earthworms casts and in biosynthesol without earthworms suggested that earthworms ate some of the micro-organisms. The main filamentous fungi genera found were Aspergillus, Trichoderma, Fusarium and Penicillium. Previous results in the literature have shown that some species from the Aspergillus and Fusarium genera were able to degrade OLA and other aliphatic esters. It could be suggested that these two genera and some bacteria were responsible for the pre-degradation of OLA, and that earthworms might eat them.

  12. Reduced greenhouse gas mitigation potential of no-tillage soils through earthworm activity.

    Science.gov (United States)

    Lubbers, Ingrid M; van Groenigen, Kees Jan; Brussaard, Lijbert; van Groenigen, Jan Willem

    2015-01-01

    Concerns about rising greenhouse gas (GHG) concentrations have spurred the promotion of no-tillage practices as a means to stimulate carbon storage and reduce CO2 emissions in agro-ecosystems. Recent research has ignited debate about the effect of earthworms on the GHG balance of soil. It is unclear how earthworms interact with soil management practices, making long-term predictions on their effect in agro-ecosystems problematic. Here we show, in a unique two-year experiment, that earthworm presence increases the combined cumulative emissions of CO2 and N2O from a simulated no-tillage (NT) system to the same level as a simulated conventional tillage (CT) system. We found no evidence for increased soil C storage in the presence of earthworms. Because NT agriculture stimulates earthworm presence, our results identify a possible biological pathway for the limited potential of no-tillage soils with respect to GHG mitigation. PMID:26337488

  13. Transcriptomic analysis of RDX and TNT interactive sublethal effects in the earthworm Eisenia fetida

    Directory of Open Access Journals (Sweden)

    Deng Youping

    2008-03-01

    Full Text Available Abstract Background Explosive compounds such as TNT and RDX are recalcitrant contaminants often found co-existing in the environment. In order to understand the joint effects of TNT and RDX on earthworms, an important ecological and bioindicator species at the molecular level, we sampled worms (Eisenia fetida exposed singly or jointly to TNT (50 mg/kg soil and RDX (30 mg/kg soil for 28 days and profiled gene expression in an interwoven loop designed microarray experiment using a 4k-cDNA array. Lethality, growth and reproductive endpoints were measured. Results Sublethal doses of TNT and RDX had no significant effects on the survival and growth of earthworms, but significantly reduced cocoon and juvenile counts. The mixture exhibited more pronounced reproductive toxicity than each single compound, suggesting an additive interaction between the two compounds. In comparison with the controls, we identified 321 differentially expressed transcripts in TNT treated worms, 32 in RDX treated worms, and only 6 in mixture treated worms. Of the 329 unique differentially expressed transcripts, 294 were affected only by TNT, 24 were common to both TNT and RDX treatments, and 3 were common to all treatments. The reduced effects on gene expression in the mixture exposure suggest that RDX might interact in an antagonistic manner with TNT at the gene expression level. The disagreement between gene expression and reproduction results may be attributed to sampling time, absence of known reproduction-related genes, and lack of functional information for many differentially expressed transcripts. A gene potentially related to reproduction (echinonectin was significantly depressed in TNT or RDX exposed worms and may be linked to reduced fecundity. Conclusions Sublethal doses of TNT and RDX affected many biological pathways from innate immune response to oogenesis, leading to reduced reproduction without affecting survival and growth. A complex interaction between mixtures of RDX and TNT was observed at the gene expression level that requires further study of the dynamics of gene expression and reproductive activities in E. fetida. These efforts will be essential to gain an understanding of the additive reproductive toxicity between RDX and TNT.

  14. Earthworms influenced by reduced tillage, conventional tillage and energy forest in Swedish agricultural field experiments

    Energy Technology Data Exchange (ETDEWEB)

    Lagerloef, Jan (SLU, Department of Ecology, Swedish University of Agricultural Sciences, Uppsala (Sweden)), Email: Jan.Lagerlof@ekol.slu.se; Paalsson, Olof; Arvidsson, Johan (SLU, Department of Soil and Environment, Swedish University of Agricultural Sciences, Uppsala (Sweden))

    2012-03-15

    We compared earthworm density, depth distribution and species composition in three soil cultivation experiments including the treatments ploughless tillage and mouldboard ploughing. Sampling was done in September 2005 and for one experiment also in 1994. By yearly sampling 1995-2005, earthworms in an energy forest of Salix viminalis were compared with those in an adjacent arable field. Sampling method was digging of soil blocks and hand sorting and formalin sampling in one cultivation experiment. Both methods were used in the energy forest and arable land comparison. In two soil cultivation experiments, highest abundances or biomass were found in ploughless tillage. Earthworm density was higher in the upper 10 cm, especially in the ploughless tillage. Earthworm density was significantly higher in the energy forest than in the arable field. Formalin sampling revealed c. 36% of the earthworm numbers found by digging in the energy forest and gave almost no earthworms in the arable field. In all treatments with soil cultivation, species living and feeding in the rhizosphere and soil dominated. One such species, Allolobophora chlorotica, was more abundant under mouldboard ploughing than ploughless tillage. Lumbricus terrestris, browsing on the surface and producing deep vertical burrows, was more common in the ploughless tillage. Species living and feeding close to the soil surface were almost only found in the energy forest, which had not been soil cultivated since 1984. The findings support earlier studies pointing out possibilities to encourage earthworms by reduced soil cultivation. This is one of the first published studies that followed earthworm populations in an energy forest plantation during several years. Explanation of earthworm reactions to management and environmental impacts should be done with consideration of the ecology of species or species groups. Earthworm sampling by formalin must always be interpreted with caution and calibrated by digging and hand-sorting sampling

  15. Freezing Rate Due to Heterogeneous Nucleation.

    Science.gov (United States)

    Vali, Gabor

    1994-07-01

    The heterogeneous nucleation of ice from supercooled water is influenced by the nature of the foreign nuclei that serve as the sites for ice embryo formation, and by the stochastic nature of the process of embryo growth to critical size. The relative roles of these two factors have been the subject of some debate, especially as they influence the way nucleation of ice is modeled in clouds. `Freezing rate' is defined as the time-dependent rate at which a population of macroscopically identical samples (e.g., drops in a volume of air) freeze due to the nuclei contained in them. Freezing rate is the combined result of nucleus content and of time dependence. The time-dependent freezing rate model (TDFR) is consistent with available empirical evidence. For droplets cooled at rates of the order of 1C per min, the nucleus content, or nucleus spectrum, predicts the freezing rate with reasonable accuracy. For samples exposed to a fixed temperature, the time dependence of the freezing rate becomes important, but the probability of freezing is not the same for each individual of the sample population. Stochastic models are not supported by the results. Application of the TDFR model and use of measured freezing nucleus data for precipitation provide a basis for the description of ice formation via immersion-freezing nucleation in cloud models. Limitations to full development of these models arise from inadequate knowledge about the freezing nucleus content of cloud water as a function of cloud evolution.

  16. Improved cryofixation applicable to freeze etching.

    Science.gov (United States)

    Bachmann, L; Schmitt, W W

    1971-09-01

    Freeze etching of solute model systems (e.g., glycerol or ferritin solutions) demonstrates that cryofixation can introduce serious artifacts due to the segregation of the dissolved or dispersed material from the solvent. Since, in principle, this problem can be reduced by increasing the cooling rate, a new technique has been developed which combines spray freezing with freeze etching. This spray-freeze-etching is applied by first spraying the specimen into a liquid cryomedium. The frozen droplets are then "glued" together with butylbenzene to form a regular freeze-etch specimen, while the temperature of the sample is kept at -85 degrees C. The results obtained by spray-freeze-etching are far superior to those obtained by standard freezing. Our results, using 5% glycerol as a test specimen, are equivalent to those obtained by the high-pressure method (1). The reduction of segregation during freezing makes freeze etching a method applicable for the investigation of solute systems. Furthermore, the study of unicellular organisms or cellular fractions by freeze etching without the use of antifreeze is made possible. PMID:4943787

  17. Denitrifying Bacteria in the Earthworm Gastrointestinal Tract and In Vivo Emission of Nitrous Oxide (N(inf2)O) by Earthworms

    OpenAIRE

    Karsten, G. R.; H. L. Drake

    1997-01-01

    Earthworms (Lumbricus rubellus and Octolasium lacteum) and gut homogenates did not produce CH(inf4), and methanogens were not readily culturable from gut material. In contrast, the numbers of culturable denitrifiers averaged 7 x 10(sup7) and 9 x 10(sup6) per g (dry weight) of gut material for L. rubellus and O. lacteum, respectively; these values were 256- and 35-fold larger than the numbers of culturable denitrifiers in the soil from which the earthworms were obtained. Anaerobically incubate...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1986-01-01

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

  19. Hot big bang or slow freeze?

    OpenAIRE

    Wetterich, C.

    2014-01-01

    We confront the big bang for the beginning of the universe with an equivalent picture of a slow freeze a very cold and slowly evolving universe. In the freeze picture the masses of elementary particles increase and the gravitational constant decreases with cosmic time, while the Newtonian attraction remains unchanged. The freeze and big bang pictures both describe the same observations or physical reality. We present a simple crossover model without a big bang singularity. In the infinite...

  20. Atmospheric freeze drying assisted by power ultrasound

    OpenAIRE

    Santacatalina Bonet, Juan Vicente; Carcel Carrin, Juan Andrs; Garca Prez, Jos Vicente; Mulet Pons, Antonio; Simal, S.

    2012-01-01

    [EN] Atmospheric freeze drying (AFD) is considered an alternative to vacuum freeze drying to keep the quality of fresh product. AFD allows continuous drying reducing fix and operating costs, but presents, as main disadvantage, a long drying time required. The application of power ultrasound (US) can accelerate AFD process. The main objective of the present study was to evaluate the application of power ultrasound to improve atmospheric freeze drying of carrot. For that pur...

  1. Interdependence of Measures in Pavlovian Conditoned Freezing

    OpenAIRE

    Wood, Suzanne C.; Anagnostaras, Stephan G.

    2011-01-01

    Pavlovian conditioned freezing is an intensively utilized paradigm that has become a standard model of memory and cognition. Despite its widespread use, the interdependence among each measure commonly reported in fear conditioning studies has not been described. Using mice, we examine the relationship of each common freezing measure (Training Baseline, Post-Shock freezing, Contextual Fear, Tone Baseline, and Tone Fear), as well as baseline locomotor activity measures, to better understand the...

  2. Hot big bang or slow freeze?

    OpenAIRE

    Wetterich, C.

    2014-01-01

    We confront the big bang for the beginning of the universe with an equivalent picture of a slow freeze - a very cold and slowly evolving universe. In the freeze picture the masses of elementary particles increase and the gravitational constant decreases with cosmic time, while the Newtonian attraction remains unchanged. The freeze and big bang pictures both describe the same observations or physical reality. We present a simple "crossover model" without a big bang singularit...

  3. PROTECTION OF FREEZE-DRIED ESCHERICHIA COLI BY TREHALOSE UPON EXPOSURE TO ENVIRONMENTAL CONDITIONS

    Science.gov (United States)

    Freeze-dried cultures of wild-type and genetically engineered strains of Escherichia coli lost their colony-forming ability upon exposure to air, visible light, and certain relative humidity levels. mendment with 100 mM trehalose increased their survival from 2000 to 4000% for up...

  4. Freeze dehydration of milk using microwave energy

    International Nuclear Information System (INIS)

    This paper presents the results of experimental studies on heat and mass transfer during a microwave freeze dehydration process. An experimental system and procedure was developed to freeze dry milk. A 2500-W microwave system with an appropriate wave guide was set up and instrumented, and a procedure was experimentally developed to obtain milk powder first by freezing milk and then dehydrating it at low pressure using microwave energy. An unsteady-state analysis was used to derive a one-dimensional mathematical model of the freeze dehydration process in a microwave electromagnetic field

  5. When hot water freezes before cold

    CERN Document Server

    Katz, J I

    2006-01-01

    I suggest that the origin of the Mpemba effect (the freezing of hot water before cold) is freezing-point depression by solutes, either gaseous or solid, whose solubility decreases with increasing temperature so that they are removed when water is heated. They are concentrated ahead of the freezing front by zone refining in water that has not been heated, reduce the temperature of the freezing front, and thereby reduce the temperature gradient and heat flux, slowing the progress of the front. I present a simple calculation of this effect, and suggest experiments to test this hypothesis.

  6. Function test of radiopharmaceutical freeze dryer

    International Nuclear Information System (INIS)

    Freeze Dryer is the main tool for radiopharmaceutical production process such as drying of radiopharmaceutical kits. To increase research and development activity of radiopharmaceutical product needs new freeze dryer type of 7948030 Freezone-Stoppering Tray Dryer to obtain high quality radiopharmaceutical dry kit. The aim of this research is ensuring freeze dryer machine can be operated well and fulfilling quality assurance programme. The working principle of freeze dryer is freeze drying process. Liquid material that originally frozen then dried with a heating process at low temperature in the vacuum freeze dryer chamber and will result phorous lyophilized product. Therefore, there are some parameters on freeze dryer operation, such as temperature, pressure, and time. They will effect on quality of radiopharmaceutical kit products. This research try for dry DTPA kit with manual or auto method for 31 hours following the procedure of drying DTPA kit. The results showed that freeze dryer can function properly in accordance with the specifications that with manual methods, freezing process reached -40C and -34 C in the auto, the drying process at 15C and 0.050 mbar on each method, and obtain dry product of DTPA kit powder (lyophilized). (author)

  7. Fundamental Technical Elements of Freeze-fracture/Freeze-etch in Biological Electron Microscopy

    Science.gov (United States)

    Freeze-fracture/freeze-etch describes a process whereby specimens, typically biological or nanomaterial in nature, are frozen, fractured, and replicated to generate a carbon/platinum "cast" intended for examination by transmission electron microscopy. Specimens are subjected to u...

  8. The influence of freezing rates on bovine pericardium tissue Freeze-drying

    OpenAIRE

    Camila Figueiredo Borgognoni; Virgilio Tattini Junior; Ana Maria Irene Bartolomeu Ayrosa; Bronislaw Polakiewicz; Adolfo Alberto Leirner; Marina Junko Shiotsu Maizato; Olga Zazuco Higa; Marisa Masumi Beppu; Ronaldo Nogueira de Moraes Pitombo

    2009-01-01

    The bovine pericardium has been used as biomaterial in developing bioprostheses. Freeze-drying is a drying process that could be used for heart valve's preservation. The maintenance of the characteristics of the biomaterial is important for a good heart valve performance. This paper describes the initial step in the development of a bovine pericardium tissue freeze-drying to be used in heart valves. Freeze-drying involves three steps: freezing, primary drying and secondary drying. The freezin...

  9. Impact of earthworms on trace element solubility in contaminated mine soils amended with green waste compost

    Energy Technology Data Exchange (ETDEWEB)

    Sizmur, Tom, E-mail: t.p.sizmur@reading.ac.uk [Soil Research Centre, Dept. Geography and Environmental Science, School of Human and Environmental Sciences, University of Reading, Whiteknights, Reading, RG6 6DW (United Kingdom); Palumbo-Roe, Barbara [British Geological Survey, Kingsley Dunham Centre, Keyworth, Nottingham, NG12 5GG (United Kingdom); Hodson, Mark E. [Soil Research Centre, Dept. Geography and Environmental Science, School of Human and Environmental Sciences, University of Reading, Whiteknights, Reading, RG6 6DW (United Kingdom)

    2011-07-15

    The common practice of remediating metal contaminated mine soils with compost can reduce metal mobility and promote revegetation, but the effect of introduced or colonising earthworms on metal solubility is largely unknown. We amended soils from an As/Cu (1150 mgAs kg{sup -1} and 362 mgCu kg{sup -1}) and Pb/Zn mine (4550 mgPb kg{sup -1} and 908 mgZn kg{sup -1}) with 0, 5, 10, 15 and 20% compost and then introduced Lumbricus terrestris. Porewater was sampled and soil extracted with water to determine trace element solubility, pH and soluble organic carbon. Compost reduced Cu, Pb and Zn, but increased As solubility. Earthworms decreased water soluble Cu and As but increased Pb and Zn in porewater. The effect of the earthworms decreased with increasing compost amendment. The impact of the compost and the earthworms on metal solubility is explained by their effect on pH and soluble organic carbon and the environmental chemistry of each element. - Graphical abstract: Display Omitted Highlights: > Compost reduced the mobility of Cu, Pb and Zn. > Compost increased the mobility of As. > Earthworms decreased water soluble As and Cu but increased Pb and Zn in porewater. > These effects are explained by the impact of the earthworms and compost on pH and DOC. - The effect of earthworms on metal solubility was due to changes in dissolved organic carbon and pH but was reduced with increasing compost amendments.

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

    Science.gov (United States)

    Mudrk, Obd?ej; Frouz, Jan

    2015-04-01

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

  11. Communicating research with the public: evaluation of an invasive earthworm education program

    Directory of Open Access Journals (Sweden)

    Erin Cameron

    2013-10-01

    Full Text Available Ecologists are increasingly encouraged by funding agencies and professional societies to communicate their research with the public. However, most receive relatively little training in how to do this effectively. Furthermore, evaluation of whether such an investment by ecologists actually achieves conservation objectives is rare. We created an education program, involving print, television, radio, and internet media, to increase awareness about earthworm invasions and to discourage anglers from dumping earthworm bait. Using pre- and post-surveys, we evaluated our programs success in reaching its target audience and in changing knowledge and behavior. Few participants (4.1% recalled seeing the program material and knowledge of the fact that earthworms are non-native in Alberta remained low (15.8% before, 15.1% after. Further, after being told about the negative effects of earthworms in forests, 46.7% of the anglers surveyed stated they would not change their bait disposal behavior in the future, with many commenting that they did not believe earthworms could be harmful. These results highlight the importance of evaluating education programs, rather than assuming they are successful. Given many participants doubts that earthworms have negative effects, both regulations and education may be needed to reduce earthworm introductions.

  12. Impact of earthworms on trace element solubility in contaminated mine soils amended with green waste compost

    International Nuclear Information System (INIS)

    The common practice of remediating metal contaminated mine soils with compost can reduce metal mobility and promote revegetation, but the effect of introduced or colonising earthworms on metal solubility is largely unknown. We amended soils from an As/Cu (1150 mgAs kg-1 and 362 mgCu kg-1) and Pb/Zn mine (4550 mgPb kg-1 and 908 mgZn kg-1) with 0, 5, 10, 15 and 20% compost and then introduced Lumbricus terrestris. Porewater was sampled and soil extracted with water to determine trace element solubility, pH and soluble organic carbon. Compost reduced Cu, Pb and Zn, but increased As solubility. Earthworms decreased water soluble Cu and As but increased Pb and Zn in porewater. The effect of the earthworms decreased with increasing compost amendment. The impact of the compost and the earthworms on metal solubility is explained by their effect on pH and soluble organic carbon and the environmental chemistry of each element. - Graphical abstract: Display Omitted Highlights: → Compost reduced the mobility of Cu, Pb and Zn. → Compost increased the mobility of As. → Earthworms decreased water soluble As and Cu but increased Pb and Zn in porewater. → These effects are explained by the impact of the earthworms and compost on pH and DOC. - The effect of earthworms on metal solubility was due to changes in dissolved organic carbon and pH but was reduced with increasing compost amendments.

  13. Conserved lamin A protein expression in differentiated cells in the earthworm Eudrilus eugeniae.

    Science.gov (United States)

    Kalidas, Ramamoorthy M; Raja, Subramanian Elaiya; Mydeen, Sheik Abdul Kader Nagoor Meeran; Samuel, Selvan Christyraj Johnson Retnaraj; Durairaj, Selvan Christyraj Jackson; Nino, Gopi D; Palanichelvam, Karuppaiah; Vaithi, Arumugaswami; Sudhakar, Sivasubramaniam

    2015-09-01

    Lamin A is an intermediate filament protein found in most of the differentiated vertebrate cells but absent in stem cells. It shapes the skeletal frame structure beneath the inner nuclear membrane of the cell nucleus. As there are few studies of the expression of lamin A in invertebrates, in the present work, we have analyzed the sequence, immunochemical conservation and expression pattern of lamin A protein in the earthworm Eudrilus eugeniae, a model organism for tissue regeneration. The expression of lamin A has been confirmed in E. eugeniae by immunoblot. Its localization in the nuclear membrane has been observed by immunohistochemistry using two different rabbit anti-sera raised against human lamin A peptides, which are located at the C-terminus of the lamin A protein. These two antibodies detected 70?kDa lamin A protein in mice and a single 65?kDa protein in the earthworm. The Oct-4 positive undifferentiated blastemal tissues of regenerating earthworm do not express lamin A, while the Oct-4 negative differentiated cells express lamin A. This pattern was also confirmed in the earthworm prostate gland. The present study is the first evidence for the immunochemical identification of lamin A and Oct-4 in the earthworm. Along with the partial sequence obtained from the earthworm genome, the present results suggest that lamin A protein and its expression pattern is conserved from the earthworm to humans. PMID:25858151

  14. The Role of Earthworms in Tropics with Emphasis on Indian Ecosystems

    International Nuclear Information System (INIS)

    The paper highlights the research carried out by different scientists in India on aspects of earthworm population dynamics and species diversity, associated with other soil fauna and microflora. It also deals with the importance of earthworm activity on physicochemical properties of soil with reference to India and other tropical countries. Stress is laid on the earthworm plant association and importance of the secretions of earthworms as plant growth stimulators. Moreover, the earthworm species reported and being utilized for vermicomposting in India are discussed, since vermicomposting is the ultimate technology which renders for the improvement of soil fertility status and plant growth. Earthworms serve as indicators of soil status such as the level of contamination of pollutants: agrochemicals, heavy metals, toxic substances, and industrial effluents; human-induced activities: land-management practices and forest degradation. In all these fields there is lacuna with respect to contributions from India when compared to the available information from other tropical countries. There is lot of scope in the field of research on earthworms to unravel the importance of these major soil macro fauna from holistic ecological studies to the molecular level.

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

    Science.gov (United States)

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

    2006-01-01

    Aim of this study was to determine effects of heavy metals on litter consumption by the earthworm Lumbricus rubellus in National Park the "Brabantsche Biesbosch", the Netherlands. Adult L. rubellus were collected from 12 polluted and from one unpolluted field site. Earthworms collected at the unpolluted site were kept in their native soil and in soil from each of the 12 Biesbosch sites. Earthworms collected in the Biesbosch were kept in their native soils. Non-polluted poplar (Populus sp.) litter was offered as a food source and litter consumption and earthworm biomass were determined after 54 days. Cd, Cu and Zn concentrations were determined in soil, pore water and 0.01 M CaCl2 extracts of the soil and in earthworms. In spite of low available metal concentrations in the polluted soils, Cd, Cu and Zn concentrations in L. rubellus were increased. The litter consumption rate per biomass was positively related to internal Cd and Zn concentrations of earthworms collected from the Biesbosch and kept in native soil. A possible explanation is an increased demand for energy, needed for the regulation and detoxification of heavy metals. Litter consumption per biomass of earthworms from the reference site and kept in the polluted Biesbosch soils, was not related to any of the determined soil characteristics and metal concentrations. ?? 2005 Elsevier GmbH. All rights reserved.

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

    Science.gov (United States)

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

    2011-01-01

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

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

    International Nuclear Information System (INIS)

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Nahmani, Johanne [Department of Soil Science, School of Human and Environmental Sciences, University of Reading, Whiteknights, Berkshire, Reading RG6 6DW (United Kingdom)]. E-mail: j.y.nahmani@reading.ac.uk; Hodson, Mark E. [Department of Soil Science, School of Human and Environmental Sciences, University of Reading, Whiteknights, Berkshire, Reading RG6 6DW (United Kingdom)]. E-mail: m.e.hodson@reading.ac.uk; Black, Stuart [Department of Archaeology, School of Human and Environmental Sciences, Whiteknights, University of Reading, Reading RG6 6DW (United Kingdom)

    2007-01-15

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

  19. Toxic effects of acetochlor and methamidophos on earthworm Eisenia fetida in phaiozem, northeast China.

    Science.gov (United States)

    Qi-xing, Zhou; Qian-ru, Zhang; Ji-dong, Liang

    2006-01-01

    Acetochlor and methamidophos are two important agrochemicals which are widely applied to agricultural production in northeast China. The investigation on the earthworm Eisenia fetida as an important type of soil animals exposed to single and binary-combined contamination of acetochlor and methamidophos was thus carried out. The single toxic effect test showed that the two agrochemicals had their toxicity to the earthworms living in phaiozem. Acetochlor had a stronger acute toxic effect on the earthworms than methamidophos. The mortality of the earthworms exposed to individual acetochlor and methamidophos changed with an increase in the exposure time and the exposed concentrations. The LD50 value of acetochlor and methamidophos toxic to the earthworms was 115.6-275.3 and 29.5-228.6 mg/kg, respectively. The weight of the earthworms was a more sensitive index compared to the mortality in indicating toxic effects of acetochlor and methamidophos in phaiozem. When considering both the mortality and the body-weight change, the combined pollution of acetochlor and methamidophos in phaiozem resulted in their synergic toxic effects on the earthworms. PMID:17078554

  20. Concentration of cadmium in Coturnix quail fed earthworms

    Energy Technology Data Exchange (ETDEWEB)

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

    1986-01-01

    Earthworms (Lumbriscus terrestris), collected from soils in southern Ontario, Canada, that had no previous history of cadmium application, contained 3 ppm cadmium. They were fed to Coturnix quail as 60% dry weight of their diet for 63 d to examine the extent of deposition of native cadmium. Cadmium in kidney, liver, and excreta was greatly elevated above that of birds fed a control diet without worms. No increase in the level of cadmium in eggs was found. The factors affecting the association of cadmium in soils and worms and their assimilation and possible toxic effects in foraging birds are discussed.

  1. La fecundidad de las lombrices rojas (Fecundity of red earthworms

    Directory of Open Access Journals (Sweden)

    Schuldt, Miguel

    2010-10-01

    Full Text Available ResumenDesde fines de la dcada del 80 se ha ampliado sustancialmente elconocimiento acerca de la biologa reproductiva de Eisenia fetida y Eisenia andrei, permitiendo optimizar las estrategias de conduccin de los lombricultivos. La fecundidad es uno de los parmetros reprobiolgicos que ms all de las fluctuaciones esperadas (0-9 lombrices / cocn ha generado discusin.SummarySince the late 1980s, knowledge about the reproductive biology of Eisenia fetida and Eisenia andrei has been applied to optimize management strategies in vermiculture. Among the reproductive biological parameters, fecundity, expected to fluctuate between 0-9 earthworms/cocoon, has generated much discussion.

  2. Macropores and earthworm species affected by agronomic intensification

    DEFF Research Database (Denmark)

    Krogh, Paul Henning; Pérès, Guénola

    soil. There is widespread recognition of soil biodiversity and biological activities that are needed to sustain soil structural properties. The detrimental consequences of a weakened functionality have been stressed in the EU Soil Strategy and hydrology in particular is related to all soil threats...... soil profile to 1 meter depth and correlated with the earthworm community consisting of 12 species dominated by the endogeics Aporrectodea caliginosa and Aporrectodea chlorotica and the anecics Aporrectodea longa and Lumbricus centralis. Medium-small macropores in the ploughing layer with diameters (Ø...

  3. Empirical maximum lifespan of earthworms is twice that of mice

    OpenAIRE

    Mulder, Christian; Baerselman, Rob; Posthuma, Leo

    2007-01-01

    We considered a Gompertzian model for the population dynamics of Eisenia andrei case-cohorts in artificial OECD soil under strictly controlled conditions. The earthworm culture was kept between 18 and 22C at a constant pH of 5.0. In all, 77 lumbricids were carefully followed for almost 9years, until the oldest died. The Eisenia median longevity is 4.25years and the oldest specimen was 8.73years. Eisenia cocoons were hand-sorted every 3weeks, washed in distilled water, placed in Petri dis...

  4. Co-Speciationof Earthwormsandtheirnephridial symbionts, Acidovorax Spp

    DEFF Research Database (Denmark)

    Lund, Marie Braad; Fritz, Michael

    2006-01-01

    Earthworms (Annelida; Lumbricidae) harbour species-specific symbiotic bacteria in their nephridia (excretory organs) where the symbionts densely colonize a specific part of the nephridia called the ampulla [1]. The symbiosis is universal among earthworms, the symbionts form a monophyletic cluster within the genus Acidovorax [2], and they are transmitted vertically [3]. For these reasons, we suggest that the earthworm-Acidovorax association has evolved by co-speciation. This hypothesis was tested by a comparative study of earthworm and symbiont phylogeny. Different earthworm species were collected in Denmark and DNA was extracted from their nephridia. Earthworm phylogeny was resolved on the basis of mitochondrial cytochrome c oxidase subunit I (COI) by direct PCR amplification and sequencing from the nephridial DNA extract. Symbiont 16S rRNA gene sequences were retrieved by cloning and sequencing the extracted DNA. The presence of the symbionts in the ampulla was verified by performing fluorescence in situ hybridization (FISH) on all worm species using an Acidovorax-specific probe. Earthworm and symbiont phylogeny was largely congruent, indicating that host and symbiont have indeed co-evolved since the initial bacterial colonization of an ancestral lumbricid worm. However, the association is complicated by the recent discovery of additional, putative symbiotic bacteria which have been detected in the ampulla of several earthworms by FISH. Identity, distribution among earthworms, and function of these non-Acidovorax symbionts are still to be investigated. [1] Knop, J. 1926. Z Morph kol Tiere, 6(3):588-624. [2] Schramm, A. et al. 2003. Environ Microbiol 5(9):804-809. [3] Davidson, S.K. & Stahl, D.A. 2006. Appl Environ Microbiol 72(1):769-775.

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

    Science.gov (United States)

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

    2014-11-01

    Metals are persistent pollutants in soils that can harm soil organisms and decrease species diversity. Animals can cope with metal contamination with the help of metallothioneins, small metal-binding proteins involved in homeostasis and detoxification of metals. We studied the expression of metallothionein with qPCR in a small, epigeic earthworm, Dendrobaena octaedra. We compared expression patterns and metal body content in earthworms collected from two sites with different metal contamination histories: Harjavalta, contaminated by a Cu-Ni smelter operational for over 50years, and Jyvskyl, an uncontaminated site. Earthworms from both sites were also experimentally exposed to different concentrations of Cu (control, 50, 100 or 200mg/kg) or Zn (control, 75, 150 or 300mg/kg) for 7, 14 or 28days 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

  6. Shock freezing berries. Effective freezing with liquid nitrogen; Beeren unter Frostschock. Tiefgefrieren mit Fluessigstickstoff

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2011-07-01

    Sensitive foods such as fruit do not freeze well at regular sub-zero temperatures. Quick freezing at extremely low temperatures is the only way of ensuring that high-value foodstuffs retain their shape and taste. Linde supplies cryogenic gases for deep freezing and also a broad portfolio of dedicated freezers. (orig.)

  7. Soil Organic Matter Particle and Presence of Earthworm Under Different Tillage Systems

    OpenAIRE

    Hortensia Brito-Vega; David Espinosa-Victoria; Carlos Fragoso; Daniel Mendoza; Nancy De la Cruz Landero; Angel Alderete-Chavez

    2009-01-01

    The objective of the present research was to study the particle of organic matter and the presence of earthworm under conservation and traditional tillage during winter and spring seasons. The sampling site was experimental field of FIRA in Villadiego, Guanajuato. The soil and earthworm sampling was carried out in monoliths of 25x25x30 cm (sidexsidexdepth), dividing the depth into strata: 0-10, 10-20 and 20-30 cm. An earthworm species was identified namely Phoenicodrilus taste under con...

  8. Production and utilization of earthworms as feeds for broilers in the Philippines

    OpenAIRE

    Barcelo P., M.

    1988-01-01

    A study on the production of earthworms was conducted using a 50 : 50 by volume of animal manures in combination with Leucaena leucocephala. A combination of sawdust, rice hull and rice bran at a proportion of 55, 35 and 10 respectively was also used as a substrate. The earthworms in each box were supplemented with either 0, 100, 200, 300 and 400 g kitchen scraps. On harvesting, hand picking the earthworms from the castings and arranging the contents of the box in a pyramid were tested. Blanc...

  9. Using of ants and earthworm to modify of soil biological quality and its effect on cocoa seedlings growth

    Science.gov (United States)

    Kilowasid, Laode Muhammad Harjoni; Budianto, Wayan; Syaf, Hasbullah; Tufaila, Muhammad; Safuan, La Ode

    2015-09-01

    Ant and earthworm can act as soil ecosystem engineers. Ant and earthworm are very dominant in smallholder cocoa plantation. The first experiment aimed to study the effect of the abundance of ants and earthworms on soil microbial activity and microfauna, and the second experiment to analyse the effect of soil modified by ants and earthworms on the cocoa seedlings growth. Ant (Ponera sp.) and earthworm (Pontoscolex sp.) collected from smallholder cocoa plantation, and kept in a container up to applied. In the first experiment, nine combinations of the abundance of ants and earthworms applied to each pot containing 3 kg of soil from smallholder cocoa plantation, and each combination of the abundance was repeated five times in a completely randomized design. After the soil was incubated for thirty days, ants and earthworms removed from the soil using hand sorting techniques. Soil from each pot was analysed for soil microbial activity, abundance of flagellates and nematodes. In the second experiment, the soil in each pot was planted with cocoa seedlings and maintained up to ninety days. The results showed the FDA hydrolytic activity of microbes, the abundance of flagellates and nematodes between the combination of the abundance of ants and earthworms have been significantly different. Dry weight of root, shoot and seedling cacao have been significantly different between the combination of the abundance of ants and earthworms. It was concluded that the combination of the abundance of ants and earthworms can be used in ecological engineering to improve soil quality.

  10. Acute toxicity of virgin and used engine oil enriched with copper nano particles in the earthworm

    International Nuclear Information System (INIS)

    In spite of development of nanotechnology and creation of new opportunities for industry, new applications and products initiated by this technology may cause harmful effects on human health and environment. Unfortunately, there is no sufficient information on the harmful effects caused by application of some nano materials; the current knowledge in this field is limited solely to the nano particles but not the final products. Nano cupper particles, as one of the common materials produced in industrial scale is widely used as additives into engine oil to reduce friction and improve lubrication. However, the difference between the effects of virgin and used conventional engine oil (CEO) and the engine oil containing cupper nano particles (NEO) on the environment is not known. Earthworm, as a one of the species which could live and survive in different sorts of earth and has a certain role in protecting the soil structure and fertility, was used in this experiment. In accordance with the recommended method of OECD.1984, Filter Paper test in 24 and 48 h based on 8 concentrations in the range of 3x10-3 - 24x10-3 ml/cm2 and Artificial Soil test in 7 and 14 days based on 7 concentrations in the range of 0.1 mg/kg - 100 g/kg were carried out to study earthworms in terms of lifetime (LC50), morphology and pathology. It was shown that the 48 h LC50 for virgin CEO, virgin NEO, used CEO(8000 km) and used NEO (8000 km) were 6x10-3, 23x10-3, 24x10-3 and 16x10-3 ml/cm2 respectively. Furthermore, 14-day LC50 in artificial soil for all cases were above 100 g/kg. It is concluded that virgin CEO is more toxic than virgin NEO. Meanwhile, the CEO shows significant reduction in toxicity after consumption and the used NEO shows more toxicity in comparison to virgin product. It seems that more investigations on the effects of final products specifically after consumption is necessary because the products after consumption have the most contact with environment and subsequently human health.

  11. Rapid bioassessment methods for assessing the toxicity of terrestrial waste sites at the Savannah River Site using the earthworm, Eisenia foetida

    International Nuclear Information System (INIS)

    Studies were conducted to assess the feasibility of using the earthworm, Eisenia foetida, to evaluate the toxicity of contaminated soils at the Savannah River Site. Survival was assessed in several uncontaminated soils, including sandy loams and clayey loams, as well as in soils contaminated with coal fines, ash, diesel fuel, and heavy metals. In addition, behavior responses, changes in biomass, and bioaccumulation of heavy metals were assessed as sublethal indicators of toxicity. The results indicate excellent survival of Eisenia foetida in uncontaminated sandy and clayey soils. No amendment of these uncontaminated soils or addition of food was necessary to sustain the worms for the 14-day test period. In contaminated soils, no significant mortality was observed, except in soils which have very low pH (< 3). However, sublethal responses were observed in earthworms exposed to several of the contaminated soils. These responses included worms clumping on the surface of the soil, worms clumping between the sides of the test container and the soil, increased burrowing times, reductions in biomass, and elevated concentrations of heavy metals in worm tissue

  12. Effects of metals on life cycle parameters of the earthworm Eisenia fetida exposed to field-contaminated, metal-polluted soils

    International Nuclear Information System (INIS)

    Two control and eight field-contaminated, metal-polluted soils were inoculated with Eisenia fetida (Savigny, 1826). Three, 7, 14, 21, 28 and 42 days after inoculation, earthworm survival, body weight, cocoon production and hatching rate were measured. Seventeen metals were analysed in E. fetida tissue, bulk soil and soil solution. Soil organic carbon content, texture, pH and cation exchange capacity were also measured. Cocoon production and hatching rate were more sensitive to adverse conditions than survival or weight change. Soil properties other than metal concentration impacted toxicity. The most toxic soils were organic-poor (1-10 g C kg-1), sandy soils (c. 74% sand), with intermediate metal concentrations (e.g. 7150-13,100 mg Pb kg-1, 2970-53,400 mg Zn kg-1). Significant relationships between soil properties and the life cycle parameters were determined. The best coefficients of correlation were generally found for texture, pH, Ag, Cd, Mg, Pb, Tl, and Zn both singularly and in multivariate regressions. Studies that use metal-amended artificial soils are not useful to predict toxicity of field multi-contaminated soils. - Soil pH, organic carbon content and texture can exert a greater influence on earthworm life cycle parameters than soil metal concentrations at metal-contaminated sites

  13. Improving Forecasts of Freezing Rain at ECMWF

    Science.gov (United States)

    Tsonevsky, Ivan; Forbes, Richard; Hewson, Tim

    2015-04-01

    Freezing rain events, though relatively rare, can be extremely debilitating and dangerous for society, with recovery times of order months or even years. Analysis of forecasts of past events by the operational ECMWF Integrated Forecast System (IFS) showed a strong tendency to incorrectly represent freezing rain as snow. Investigations highlighted that this was primarily because the re-freezing process in IFS, following hydrometeors as they descend, was parametrised with the same time-scale as the melting process. In reality the time-scale for re-freezing should, in general, be much longer. The model physics were changed accordingly, and the results in terms of forecast quality were positive and very striking. Coupled with these physics changes new IFS output was developed for users which shows precipitation type at the surface (rain, snow, wet snow, sleet, freezing rain, ice pellets). The changes to the physics will be described in detail, and their impact will be illustrated by comparing forecast output for past events in new and old model versions, in terms of precipitation type and intensity. Illustrations will include short-range deterministic forecasts from 'HRES' (the high resolution ECMWF model), and longer range probabilistic forecasts of freezing rain occurrence from the ensemble. There will also be reference to issues requiring further work/investigation, such as high level convection in potential freezing rain cases, freezing drizzle generated in supercooled shallow clouds, and IFS retention of the 'warm nose' in which melting occurs.

  14. Freeze concentration of lime juice

    Directory of Open Access Journals (Sweden)

    Ampawan Tansakul

    2008-11-01

    Full Text Available The main objective of this research was to study the effects of processing conditions, i.e. cooling medium temperature (-6, -12 and -18?C and scraper blade rotational speed (50, 100 and 150 rpm on the freeze concentration of lime juice. The initial soluble solid content of lime juice was 7.6? Brix. Results showed that soluble solid content of lime juice increased as cooling medium temperature decreased while scraper blade rotational speed increased. It was also found that the processing condition with -18?C cooling medium temperature and 150 rpm rotational speed of the scraper blade was the best among all studied conditions, although the loss of the soluble solids with ice crystals during ice separation was relatively high at 35%.

  15. Earthworm coelomocytes as nanoscavenger of ZnO NPs

    Science.gov (United States)

    Gupta, Shruti; Kushwah, Tanuja; Yadav, Shweta

    2014-05-01

    Earthworms can `biotransform' or `biodegrade' chemical contaminants, rendering them harmless in their bodies, and can bioaccumulate them in their tissues. They `absorb' the dissolved chemicals through their moist `body wall' due to the interstitial water and also ingest by `mouth' while soil passes through the gut. Since the advent of the nanotechnology era, the environmental sink has been continuously receiving engineered nanomaterials as well as their derivatives. Our current understanding of the potential impact of nanomaterials and their natural scavenger is limited. In the present investigation, we studied the cellular uptake of ZnO nanoparticles (NPs) by coelomocytes especially by chloragocytes of Eisenia fetida and their role as nanoscavenger. Results from exposure to 100- and 50-nm ZnO NPs indicate that coelomocytes of the earthworm E. fetida show no significant DNA damage at a dose lower than 3 mg/l and have the potential ability to uptake ZnO NPs from the soil ecosystem and transform them into microparticles.

  16. The binding interactions of imidacloprid with earthworm fibrinolytic enzyme

    Science.gov (United States)

    Wang, Yan-Qing; Zhang, Hong-Mei; Chen, Tao

    2014-08-01

    In this paper, several studies were conducted to elucidate the binding mechanism of earthworm fibrinolytic enzyme (EFE) with imidocloprid (IMI) by using theoretical calculation, fluorescence, UV-vis, circular dichroism spectroscopy and an enzymatic inhibition assay. The spectral data showed that the binding interactions existed between IMI and EFE. The binding constants, binding site, thermodynamic parameters and binding forces were analyzed in detail. The results indicate a single class of binding sites for IMI in EFE and that this binding interaction is a spontaneous process with the estimated enthalpy and entropy changes being 2.195 kJ mol-1 and 94.480 J mol-1 K-1, respectively. A single class of binding site existed for IMI in EFE. The tertiary or secondary structure of EFE was partly destroyed by IMI. The visualized binding details were also exhibited by the theoretical calculation and the results indicated that the interaction between IMI and Phe (Tyr, or Trp) or EFE occurred. Combining the experimental data with the theoretical calculation data, we showed that the binding forces between IMI and EFE were mainly hydrophobic force accompanied by hydrogen binding, and ?-? stacking. In addition, IMI did not obviously influence the activity of EFE. In a word, the above analysis offered insights into the binding mechanism of IMI with EFE and could provide some important information for the molecular toxicity of IMI for earthworms.

  17. LBP/BPI homologue in Eisenia andrei earthworms.

    Science.gov (United States)

    kanta, Frantiek; Prochzkov, Petra; Roubalov, Radka; Dvo?k, Ji?; Bilej, Martin

    2016-01-01

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

  18. Biosynthesis of luminescent quantum dots in an earthworm

    Science.gov (United States)

    Strzenbaum, S. R.; Hckner, M.; Panneerselvam, A.; Levitt, J.; Bouillard, J.-S.; Taniguchi, S.; Dailey, L.-A.; Khanbeigi, R. Ahmad; Rosca, E. V.; Thanou, M.; Suhling, K.; Zayats, A. V.; Green, M.

    2013-01-01

    The synthesis of designer solid-state materials by living organisms is an emerging field in bio-nanotechnology. Key examples include the use of engineered viruses as templates for cobalt oxide (Co3O4) particles, superparamagnetic cobalt-platinum alloy nanowires and gold-cobalt oxide nanowires for photovoltaic and battery-related applications. Here, we show that the earthworm's metal detoxification pathway can be exploited to produce luminescent, water-soluble semiconductor cadmium telluride (CdTe) quantum dots that emit in the green region of the visible spectrum when excited in the ultraviolet region. Standard wild-type Lumbricus rubellus earthworms were exposed to soil spiked with CdCl2 and Na2TeO3 salts for 11 days. Luminescent quantum dots were isolated from chloragogenous tissues surrounding the gut of the worm, and were successfully used in live-cell imaging. The addition of polyethylene glycol on the surface of the quantum dots allowed for non-targeted, fluid-phase uptake by macrophage cells.

  19. Neurotropic and neuroprotective activities of the earthworm peptide Lumbricusin

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dae Hong; Lee, Ik Hwan; Nam, Seung Taek; Hong, Ji; Zhang, Peng [Department of Life Science, College of Natural Science, Daejin University, Pocheon, Gyeonggido 487-711 (Korea, Republic of); Hwang, Jae Sam [Department of Agricultural Biology, National Academy of Agricultural Science, RDA, Suwon 441-707 (Korea, Republic of); Seok, Heon [Department of Biomedical Engineering, Jungwon University, Goesan, Chungcheongbukdo 367-700 (Korea, Republic of); Choi, Hyemin; Lee, Dong Gun [School of Life Sciences, KNU Creative Bioresearch Group (BK21 Plus Program), College of Natural Sciences, Kyungpook National University, Daehak-ro 80, Buk-gu, Daegu 702-701 (Korea, Republic of); Kim, Jae Il [School of Life Sciences, Gwangju Institute of Science and Technology, Oryong-dong, Buk-gu, Gwangju 500-712 (Korea, Republic of); Kim, Ho, E-mail: hokim@daejin.ac.kr [Department of Life Science, College of Natural Science, Daejin University, Pocheon, Gyeonggido 487-711 (Korea, Republic of)

    2014-06-06

    Highlights: • 11-mer peptide Lumbricusin, a defensin like peptide, is isolated from earthworm. • We here demonstrated that Lumbricusin has neurotropic and neuroprotective effects. • p27 degradation by Lumbricusin mediates effects of Lumbricusin on neuronal cells. - Abstract: We recently isolated a polypeptide from the earthworm Lumbricus terrestris that is structurally similar to defensin, a well-known antibacterial peptide. An 11-mer antibacterial peptide (NH{sub 2}-RNRRWCIDQQA), designated Lumbricusin, was synthesized based on the amino acid sequence of the isolated polypeptide. Since we previously reported that CopA3, a dung beetle peptide, enhanced neuronal cell proliferation, we here examined whether Lumbricusin exerted neurotropic and/or neuroprotective effects. Lumbricusin treatment induced a time-dependent increase (∼51%) in the proliferation of human neuroblastoma SH-SY5Y cells. Lumbricusin also significantly inhibited the apoptosis and decreased viability induced by treatment with 6-hydroxy dopamine, a Parkinson’s disease-mimicking agent. Immunoblot analyses revealed that Lumbricusin treatment increased ubiquitination of p27{sup Kip1} protein, a negative regulator of cell-cycle progression, in SH-SY5Y cells, and markedly promoted its degradation. Notably, adenoviral-mediated over-expression of p27{sup Kip1} significantly blocked the antiapoptotic effect of Lumbricusin in 6-hydroxy dopamine-treated SH-SY5Y cells. These results suggest that promotion of p27{sup Kip1} degradation may be the main mechanism underlying the neuroprotective and neurotropic effects of Lumbricusin.

  20. Scaling of the hydrostatic skeleton in the earthworm Lumbricus terrestris.

    Science.gov (United States)

    Kurth, Jessica A; Kier, William M

    2014-06-01

    The structural and functional consequences of changes in size or scale have been well studied in animals with rigid skeletons, but relatively little is known about scale effects in animals with hydrostatic skeletons. We used glycol methacrylate histology and microscopy to examine the scaling of mechanically important morphological features of the earthworm Lumbricus terrestris over an ontogenetic size range from 0.03 to 12.89 g. We found that L. terrestris becomes disproportionately longer and thinner as it grows. This increase in the length to diameter ratio with size means that, when normalized for mass, adult worms gain ~117% mechanical advantage during radial expansion, compared with hatchling worms. We also found that the cross-sectional area of the longitudinal musculature scales as body mass to the ~0.6 power across segments, which is significantly lower than the 0.66 power predicted by isometry. The cross-sectional area of the circular musculature, however, scales as body mass to the ~0.8 power across segments, which is significantly higher than predicted by isometry. By modeling the interaction of muscle cross-sectional area and mechanical advantage, we calculate that the force output generated during both circular and longitudinal muscle contraction scales near isometry. We hypothesize that the allometric scaling of earthworms may reflect changes in soil properties and burrowing mechanics with size. PMID:24871920

  1. USE OF VARIOUS BAITS FOR EXTRACTION OF EARTHWORMS FROM VERMICOMPOST

    Directory of Open Access Journals (Sweden)

    Joanna Kostecka

    2015-11-01

    Full Text Available During vermicomposting, earthworm grower has to overcome a lot of different problems. For instance, in case of a sudden requirement to sell earthworms it is useful to have the ability to collect them in one place. Fresh food extraction is an effective and neutral way to do it. The efficiency of gathering and extracting E. fetida from the vermicompost was studied, using a fresh bait method. Experiments were carried out in the laboratory (at the mean temperature of 200.5 C in pots filled with vermicompost. Generally, two hundreds of adult E. fetida were put in every pot and left there for 24 hours. After such acclimatization, various baits were inserted to every pot. Different experiments allowed to conclude that: 1repeated bait exchange was more efficient in extracting worms from vermicompost than bait laid once for a longer time; 2extracting worms from the bait in the morning was quicker than extracting them in the evening; 3addition of valerian (Valeriana officinalis, nettle (Urtica dioica, and flaxseeds to cattle manure could resulted in better extraction than pure manure; 4dry valerian was more effective than steamed one, but on other hand, steaming of nettle and flaxseeds was giving better results in collecting worms in the bait.

  2. Vacuolar membrane lesions induced by a freeze-thaw cycle in protoplasts isolated from deacclimated tubers of Jerusalem artichoke (Helianthus tuberosus L.).

    Science.gov (United States)

    Murai, M; Yoshida, S

    1998-01-01

    The processes of freezing injury in Jerusalem artichoke (Helianthus tuberosus L.) tubers were studied using protoplasts isolated from cold-acclimated and deacclimated tubers. Prior to freezing, protoplasts were preloaded with 10 microM fluorescein diacetate (FDA) in an isotonic sorbitol solution. After freeze-thawing at various temperatures, cell viability was evaluated under a fluorescence microscope. In cold-acclimated tubers, more than 80% of protoplasts survived freezing to -20 degrees C. By contrast, in deacclimated tubers, the cell survival abruptly declined after freezing to temperatures below -5 degrees C. Thus, freezing tolerance differed significantly between protoplasts isolated from cold-acclimated and deacclimated tubers. Two distinct types of cell injury, which were caused by either damage to plasma membrane (cell-lysis type) or by damage to the vacuolar membrane (abnormal-staining type), were observed, depending on the cold hardiness and freezing temperature. In the cells of the abnormal-staining type, shrinkage of the central vacuolar space and simultaneous acidification of the cytoplasmic space were characteristically observed immediately before complete cell-rehydration during thawing. The decrease in freezing tolerance of protoplasts after deacclimation was suggested to be due mainly to destabilization of the vacuolar membrane by freeze-induced dehydration stress. PMID:9517005

  3. Earthworms as soil quality indicators: local and scientific knowledge in rice management systems

    Directory of Open Access Journals (Sweden)

    Ana Cludia Rodrigues de LIMA

    2010-01-01

    Full Text Available Farmers from Camaqu, Rio Grande do Sul, Brazil, were shown to have a holistic view of the quality of the soil they are cultivating. Progress towards sustainable land management will come from the synergy of both local and formal scientific knowledge. However, the literature on soil quality largely fails to address such integration. The objective of the present work was to highlight the potential use of earthworms in indicating soil quality from a rice farmers' perspective and using a formal scientific assessment in Camaqu. From a study of local knowledge of farmers and soil analysis it was shown that earthworms are an important component of soil quality. Although the farmers considered that earthworms indicated the quality of their soils, they hardly used them as indicators, due to their limited observation of these animals. A decision-support system to evaluate the options for using earthworms in sustainable management is needed in rice production systems.

  4. Earthworms in Central European Wetlands: Do they contribute to biodiversity of biosphere reserves ?.

    Czech Academy of Sciences Publication Activity Database

    Pil, Vclav

    Praha : Komitt MAB, 2002. s. 37. [EuroMAB Workshop. 13.10.2002-18.10.2002, Mikulov] Institutional research plan: CEZ:AV0Z6066911 Keywords : earthworms * Central European Wetlands Subject RIV: EH - Ecology, Behaviour

  5. Assemblages of earthworms and collembolans in fen soil as affected by landslide.

    Czech Academy of Sciences Publication Activity Database

    Sterzy?ska, M.; Nicia, P.; Pil, Vclav

    Coimbra : University of Coimbra, 2012. s. 30. [International Colloquium on Soil Zoology /16./. 06.08.2012-10.08.2012, Coimbra] Institutional support: RVO:60077344 Keywords : earthworms * collembolans * fen soil * landslide Subject RIV: EH - Ecology, Behaviour

  6. The effects of earthworms on microbial communities: comparison of soil and cave populations of Aporrectodea rosea

    Czech Academy of Sciences Publication Activity Database

    Pil, Vclav; Elhottov, Dana; Koubov, Anna; Kahounov, Ludmila

    Coimbra : University of Coimbra, 2012. s. 104. [International Colloquium on Soil Zoology /16./. 06.08.2012-10.08.2012, Coimbra] Institutional support: RVO:60077344 Keywords : earthworms * microbial communities * soil and cave populations Subject RIV: EH - Ecology, Behaviour

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

    Science.gov (United States)

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

    2014-07-01

    Herbicides containing glyphosate are widely used in agriculture and private gardens, however, surprisingly little is known on potential side effects on non-target soil organisms. In a greenhouse experiment with white clover we investigated, to what extent a globally-used glyphosate herbicide affects interactions between essential soil organisms such as earthworms and arbuscular mycorrhizal fungi (AMF). We found that herbicides significantly decreased root mycorrhization, soil AMF spore biomass, vesicles and propagules. Herbicide application and earthworms increased soil hyphal biomass and tended to reduce soil water infiltration after a simulated heavy rainfall. Herbicide application in interaction with AMF led to slightly heavier but less active earthworms. Leaching of glyphosate after a simulated rainfall was substantial and altered by earthworms and AMF. These sizeable changes provide impetus for more general attention to side-effects of glyphosate-based herbicides on key soil organisms and their associated ecosystem services.

  8. Earthworm Ecology in the Northern Part of Iran: With an Emphasis on Compost Worm Eisenia fetida

    Directory of Open Access Journals (Sweden)

    G.A. Omrani

    2005-01-01

    Full Text Available In the present study, Northern part of Iran was chosen as study area. Four hundred samples of earthworms were collected by three methods (hand-sorting, chemical and heat extraction of which 352 and 20 were mature and immature earthworms, respectively from different parts of the area. Following the method introduced by Graff the earthworms were placed in formaldehyde (5 and 10% and ethyl alcohol (60%. The morphological observations showed the presence of eight species including seven specimens of Lumbricidae: A. caliginosa, A. kaznakovi, A. jassyensis, A. rosea, D. veneta, D. byblica, E. fetida and a specimen of Megascolecidae: P. indica. The abundance of E. fetida was 18.1% with large distribution over the area that makes this species an easily available earthworm in rearing industry and in organic waste management.

  9. Earthworm Casts (Pheretema sp. Nutrient Contents of Nampong Soil Series (Ustoxic Quartzipsamment in Northeast Thailand

    Directory of Open Access Journals (Sweden)

    T. Chuasavathi

    2001-01-01

    Full Text Available This earthworm cast experiment was carried out at four different sites of Nampong soil series (Ustoxic quartzipsamment namely dipterocarp forest, tamarind orchard farm, grazing pasture, and sugarcane plantation. The results showed that earthworm casts of the four locations contented different levels of nutrients. The highest nutrient contents were found with Tamarind orchard farm followed by Dipterocarp forest, grazing pasture, and sugarcane plantation, respectively. Data on nutrient contents (NPK, Ca, Mg, and Na of earthworm casts of each location were much higher than that of their respective soils. Earthworm casts could help to improve soil properties particularly Nampong soil series, which contented low level of soil fertility. This may help to improve crop yield for sustainable agriculture.

  10. Earthworm populations in soils contaminated by the Chernobyl atomic power station accident, 1986-1988

    International Nuclear Information System (INIS)

    A study of earthworm populations in the 30 km zone around the Chernobyl atomic power station was carried out in 1986-1988. Significant differences in earthworm population numbers were found between highly contaminated and control plots in summer and autumn 1986 and in April 1987. But in the autumn of 1988 the earthworm population numbers in contaminated plots were higher than in the control plots. The ratio of mature to immature specimens was higher in 1986 in the contaminated plots in comparison with the control plots. Only one species of earthworms, Dendrobaena octahedra, was found in contaminated forest plots during the first 2 yr following the accident but in the control forest plots Apporectodea caliginosa was also found. (author)

  11. [Effects of methamidophos and copper on ecological detoxification of acetochlor by earthworm in phaeozem].

    Science.gov (United States)

    Liang, Jidong; Zhou, Qixing

    2006-10-01

    By using microcosm culture method, this paper studied the dynamic changes of acetochlor degradation by earthworm in phaeozem with methamidophos or copper addition, aimed to approach the feasibility of using earthworm to intensify the detoxification of acetochlor. The results showed that the dynamics of acetochlor degradation accorded with the first-order reaction kinetics, whether earthworm existed or not. The activities of earthworm accelerated the detoxification of acetochlor, and the coexistence of methamidophos or copper with acetochlor evidently inhibited the degradation of acetochlor. The coexistence of methamidophos and acetochlor or of copper and higher concentration acetochlor altered the dynamics of acetochlor degradation, while the coexistence of copper and lower concentration acetochlor didn't have any obvious effect on the detoxification of acetochlor. PMID:17209401

  12. Effects of earthworm Pontoscolex corethrurus on distribution of acaricida dicofol in a Podzolic soil

    International Nuclear Information System (INIS)

    The aim of this work was to study the influence of earthworm on pesticides distribution in a Podzolic soil. The experimental model used was a microcosm filled with sieved soil to a final density of 1.25 g cm-3. In microcosms with or without Pontoscolex corethurus 14C-dicofol was applied, and after a period of 52 days strong rain simulation was performed. In the layer of 0-1 cm 75% of the radioactivity in the soil without earthworms were recovered, and in the soil with earthworms the recovery was 9% inferior. In the deepest layers the values of the radioactivity were below 20% and the differences among the treatments did not surpass 2%. This earthworm species of large occurrence in Brazil showed no important influence on the distribution of the pesticide in soil

  13. Taxonomic composition and physiological and biochemical properties of bacteria in the digestive tracts of earthworms

    Science.gov (United States)

    Byzov, B. A.; Tikhonov, V. V.; Nechitailo, T. Yu.; Demin, V. V.; Zvyagintsev, D. G.

    2015-03-01

    Several hundred bacterial strains belonging to different taxa were isolated and identified from the digestive tracts of soil and compost earthworms. Some physiological and biochemical properties of the bacteria were characterized. The majority of intestinal bacteria in the earthworms were found to be facultative anaerobes. The intestinal isolates as compared to the soil ones had elevated activity of proteases and dehydrogenases. In addition, bacteria associated with earthworms' intestines are capable of growth on humic acids as a sole carbon source. Humic acid stimulated the growth of the intestinal bacteria to a greater extent than those of the soil ones. In the digestive tracts, polyphenol oxidase activity was found. Along with the data on the taxonomic separation of the intestinal bacteria, the features described testified to the presence of a group of bacteria in the earthworms intestines that is functionally characteristic and is different from the soil bacteria.

  14. Viability of Bifidobacterium Pseudocatenulatum G4 after Spray-Drying and Freeze-Drying

    OpenAIRE

    Stephenie Wong; Barka Mohammed Kabeir; Shuhaimi Mustafa; Rosfarizan Mohamad; Anis Shobirin Meor Hussin; Mohd Yazid Manap

    2010-01-01

    Viability of Bifidobacterium pseudocatenulatum G4 following spray-drying and freeze-drying in skim milk was evaluated. After spray-drying, the strain experienced over 99% loss in viability regardless of the air outlet temperature (75 and 85 C) and the heat-adaptation temperature (45 and 65 C, 30 min). The use of heat-adaptation treatment to improve the thermotolerance of this strain was ineffective. On the other hand, the strain showed a superior survival at 71.65%82.07% after freeze-dryin...

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

    Science.gov (United States)

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

    2014-10-01

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

  16. Earthworms and radionuclides, with experimental investigations on the uptake and exchangeability of radiocaesium

    Energy Technology Data Exchange (ETDEWEB)

    Brown, S.L.; Bell, J.N.B. [Imperial College, Silwood Park, Ascot (United Kingdom). Dept. of Biology

    1995-04-01

    The potential influence of earthworm activity on the mobility of radionuclides in soils and their subsequent availability for uptake by plants and transfer to higher trophic levels is briefly reviewed. The accumulation of caesium by the earthworm Aporrectodea longa from soil and from plant litter was investigated in laboratory experiments, as was the effect of reworking (through burrowing and ingestion) soil and soil with added organic material, on the extractability of caesium (ammonium acetate extraction). (author).

  17. The earthwormVerminephrobacter symbiosis: an emerging experimental system to study extracellular symbiosis

    OpenAIRE

    MarieBraadLund; KasperUrupKjeldsen; AndreasSchramm

    2014-01-01

    Almost all Lumbricid earthworms (Oligochaeta: Lumbricidae) harbor extracellular species-specific bacterial symbionts of the genus Verminephrobacter (Betaproteobacteria) in their nephridia. The symbionts have a beneficial effect on host reproduction and likely live on their hosts waste products. They are vertically transmitted and presumably associated with earthworms already at the origin of Lumbricidae 62 136 million years ago. The Verminephrobacter genomes carry signs of bottleneck-induc...

  18. Earthworms and Humans in Vitro: Characterizing Evolutionarily Conserved Stress and Immune Responses to Silver Nanoparticles

    DEFF Research Database (Denmark)

    Hayashi, Yuya; Engelmann, Pter; Foldbjerg, Rasmus; Szab, Mariann; Somogyi, Ildik; Pollk, Edit; Molnr, Lszl; Autrup, Herman; Sutherland, Duncan S; Scott-Fordsmand, Janeck James; Heckmann, Lars-Henrik

    2012-01-01

    Little is known about the potential threats of silver nanoparticles (AgNPs) to ecosystem health, with no detailed report existing on the stress and immune responses of soil invertebrates. Here we use earthworm primary cells, cross-referencing to human cell cultures with a particular emphasis on the conserved biological processes, and provide the first in vitro analysis of molecular and cellular toxicity mechanisms in the earthworm Eisenia fetida exposed to AgNPs (83 22 nm). While we observed a...

  19. Immunohistochemistry of Heat Shock Protein 70 (Hsp70) on Earthworm (Lumbricus terrestris) in Gold Mining Sites

    OpenAIRE

    Setya Widi Ayuning; Diana Arfiati; Yenny Risjani

    2014-01-01

    The traditional gold mining in Cempaka, Banjarbaru, South Kalimantan, Indonesia used mercury in order to separate the gold with a fine sand and rocks. Mercury can impair the function of the cellular and organism physiology that live in the mining sites. In cellular on earthworm may adapt to help in repairing cell damage with expression of HSP70 proteins. This study was conducted in November 2012 to September 2014. Sampling of soil and earthworms do in Banjarbaru village (control) and in paddy...

  20. Earthworms - role in soil fertility to the use in medicine and as a food

    OpenAIRE

    M Grdia; K Gri?; MD Grdia

    2013-01-01

    Earthworms are important regulators of soil structure and dynamics of soil organic matter. They are a major component of soil fauna communities in most ecosystems and comprise a large proportion of macro fauna biomass. Their activities are beneficial because they can enhance soil nutrient cycling through the rapid incorporation of detritus into mineral soil. However, mucus production associated with water excretion in earthworm guts also enhances the activity of other beneficial soil microorg...

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

    OpenAIRE

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

    2012-01-01

    Actinomycetes from earthworm castings were isolated and screened for their antimicrobial activity and industrial enzymes. A total of 48 isolates were obtained from 12 samples of earthworm castings. Highest numbers of isolates were recovered from forest site (58.33 %) as compared to grassland (25%) and agricultural land (16.66%). The growth patterns, mycelial coloration of abundance actinomycetes were documented. The dominant genera Identified by cultural, morphological and physiological chara...

  2. Radioresistance of aboriginal earthworms of Absheron peninsula in radioactive model systems

    International Nuclear Information System (INIS)

    Full tex:Soil animals are the most suitable biological indicators of radioactive pollution because they are parts of nutritional chains and webs, occur in relatively high numbers and can be collected during most parts of the year.The use of earthworms in the soils from Ramana iodine plant area of Absheron peninsula, which is rich with radionuclide and in the soil mixed with RaCl2 and UO2SO4 salt solutions in different concentrations, for resistance to ionizing radiation in soil is reviewed.Effect of radionuclides on vital functions of earthworms and determination of radionuclides (before and after experiments) in contaminated soils by ?-spectrometer were carried out in laboratory condition during a month. Regarding to ?-spectrometric results there were determined that earthworms had absorbed most of radioactive elements and allocated them as coprogenous substances on the upper layer of soil. In Ramana soils mostly the 238U radionuclides were highly accumulated in gut cells of the earthworms. By the influence of radioactive elements it was shown that the earthworms from Ramana iodine plant territory variants had proved particularly sensitive to an increased Ra-radiation background and to iodine factor.It was interestingly established the proportional dependence between rising level of accumulation in earthworms' body and in their coprolites and increasing of radioactive salts containing in the soils treated by UO2SO4 and RaCl2 solutions.Thus there is different level of radioresistance for earthworms and they are among the best bioindicators of polluted soils. There was an obvious perspective of using of earthworms as bioremediators in polluted soil with radionuclides in future as well.

  3. Radioresistance of aboriginal earthworms of Absheron peninsula in radioactive model systems

    International Nuclear Information System (INIS)

    Full text : Soil animals are the most suitable biological indicators of radioactive pollution because they are parts of nutritional chains and webs, occur in relatively high numbers and can be collected during most parts of the year. The use of earthworms in the soils from Ramana (Baku) iodine plant area of Absheron peninsula, which is rich with radionuclide and in the soil mixed with RaCl2 and UO2SO4 salt solutions in different concentrations, for resistance to ionizing radiation in soil is reviewed. Effect of radionuclides on vital functions of earthworms and determination of radionuclides (before and after experiments) in contaminated soils by ?-spectrometer were carried out in laboratory condition during a month. Regarding to ?-spectrometric results there were determined that earthworms had absorbed most of radioactive elements and allocated them as coprogenous substances on the upper layer of soil. In Ramana soils mostly the 238U radionuclides were highly accumulated in gut cells of the earthworms. By the influence of radioactive elements it was shown that the earthworms from Ramana iodine plant territory variants had proved particularly sensitive to an increased Ra-radiation background and to iodine factor. It was interestingly established the proportional dependence between rising level of accumulation in earthworms body and in their coprolites and increasing of radioactive salts containing in the soils treated by UO2SO4 and RaCl2 solutions. Thus there is different level of radioresistance for earthworms and they are among the best bioindicators of polluted soils. There was an obvious perspective of using of earthworms as bioremediators in polluted soil with radionuclides in future as well.

  4. Infestation of natural populations of earthworm cocoons by rhabditid and cephalobid nematodes

    DEFF Research Database (Denmark)

    Kraglund, HO; Ekelund, Flemming

    2002-01-01

    Nematodes infested 13 of 100 earthworm cocoons from a compost pile and 17 of 197 cocoons from a permanent pasture soil. Between one and 2000 nematodes were found within the infested cocoons. All nematodes found in cocoons from the compost pile belonged to the genus Rhabditis, while Rhabditis spp. as well as members of Cephalobidae infested earthworm cocoons in the pasture soil. In cultures established from cocoons found in the pasture soil, at least five different types of nematodes belonging to...

  5. Implementation of earthworm-assisted constructed wetlands to treat wastewater and possibility of using alternative plants in constructed wetlands

    OpenAIRE

    Chiarawatchai, Nathasith

    2010-01-01

    The aim of this research was to add the earthworms into the constructed wetlands, both in Germany and Thailand, in order to investigate whether they could improve the treatment performances. For Germany, earthworm-assisted constructed wetlands exhibited better treatment efficiency than conventional vertical subsurface-flow constructed wetlands and the unplanted constructed wetlands with earthworms. For Thailand, the production of sludge on the surface of wetlands was reduced by 40% with eart...

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

    OpenAIRE

    Joimel, Sophie; MAKOWSKI, DAVID; Makowski, Daniel

    2013-01-01

    Pesticide risk assessments include experiments designed to measure the effect of pesticides on earthworms using the Eisenia fetida fetida or Eisenia fetida andrei species. There is no clear consensus in the literature on the sensitivity of different earthworm species to pesticides. We performed a meta-analysis on the sensitivity of several earthworm species to pesticides to determine the most sensitive species, and to discuss their suitability for European homologation tests. A dataset i...

  7. Exploring the Nature of Contact Freezing

    Science.gov (United States)

    Kiselev, A. A.; Hoffmann, N.; Duft, D.; Leisner, T.

    2012-12-01

    The freezing of supercooled water droplets upon contact with aerosol particles (contact nucleation of ice) is the least understood mechanism of ice formation in atmospheric clouds. Although experimental evidences suggest that some aerosols can be better IN in the contact than in the immersion mode (that is, triggering ice nucleation at higher temperature), no final explanation of this phenomena currently exists. On the other hand, the contact freezing is believed to be responsible for the enhanced rate of secondary ice formation occasionally observed in LIDAR measurements in the cold mixed phase clouds. Recently we have been able to show that the freezing of supercooled droplets electrodynamically levitated in the laminar flow containing mineral dust particles (kaolinite) is a process solely governed by a rate of collisions between the supercooled droplet and the aerosol particles. We have shown that the probability of droplet freezing on a single contact with aerosol particle may differ over an order of magnitude for kaolinite particles having different genesis and morphology. In this presentation we extend the study of contact nucleation of ice and compare the IN efficiency measured for DMA-selected kaolinite, illite and hematite particles. We show that the freezing probability increases towards unity as the temperature decreases and discuss the functional form of this temperature dependence. We explore the size dependence of the contact freezing probability and show that it scales with the surface area of the particles, thus resembling the immersion freezing behavior. However, for all minerals investigated so far, the contact freezing has been shown to dominate over immersion freezing on the short experimental time scales. Finally, based on the combined ESEM and electron microprobe analysis, we discuss the significance of particle morphology and variability of chemical composition on its IN efficiency in contact mode.

  8. Protein freeze concentration and micro-segregation analysed in a temperature-controlled freeze container

    Directory of Open Access Journals (Sweden)

    Ulrich Roessl

    2015-06-01

    Full Text Available To examine effects of varied freezing conditions on the development of spatial heterogeneity in the frozen protein solution, macroscopic freeze concentration and micro-segregation of bovine serum albumin (BSA were investigated in a temperature-controlled 200-ml freeze container. Freezing to ?40C promoted formation of protein concentration gradients (69114?gml?1 in frozen samples taken from 12 different freezer positions, whereby slow freezing in 4h or longer facilitated the evolution of strong spatial heterogeneities and caused local concentration increases by 1.15-fold relative to the initial protein concentration (100?gml?1. To visualize protein micro-segregation during phase separation, BSA was conjugated with fluorescein isothiocyanate and confocal laser scanning fluorescence microscopy was used to localize and size the freeze-concentrated protein regions. Slow freezing resulted in distinctly fewer and larger protein domains in the frozen bulk than fast freezing. Surface stress on the protein during freezing would therefore be minimized at low cooling rates; microscopic freeze concentration would however be highest under these conditions, potentially favoring protein aggregation.

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

    Science.gov (United States)

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

    2015-07-15

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

  10. Radiocesium ([sup 137]Cs) from the Chernobyl reactor in Eurasian woodcock and earthworms in Norway

    Energy Technology Data Exchange (ETDEWEB)

    Kalas, J.A. (Norwegian Institute for Nature Research, Trondheim (Norway)); Bretten, S.; Njastad, O. (Univ. of Trondheim (Norway)); Byrkjedal, I. (Univ. of Bergen (Norway))

    1994-01-01

    To understand the ecological effects of the Chernobyl reactor accident, we investigated radiocesium ([sup 137]Cs) levels in Eurasian woodcock (Scolopax rusticola), earthworms (Lambricidae), litter (dead organic materials lying on the ground), humus (beneath litter 2 cm deep), and mineral soil samples (3-6 cm deep) from a heavily effected (20-60 kBq/m[sup 2][1 Bq = 1 nuclear fission/sec]) area in Norway. The highest concentrations measured in earthworms (1988 median = 142 Bq/Kg) and woodcock (1986 median = 730 Bq/kg) for human food (600 Bq/kg fresh mass) only were found in woodcock during 1986. Radiocesium concentrations decreased (P < 0.001) in earthworms (40%) and woodcock (95%) from 1986 to 1990. There was no reduction in total radiocesium in soil over the same period. The relatively high radiocesium concentrations in woodcock during 1986 and the decreasing radiocesium ratio in woodcock to earthworms during the first years following fallout could have been caused by woodcock ingesting abiotic radiocesium with earthworms. The decrease in radiocesium in woodcock and earthworms during the study (1986-90) probably resulted from decreasing bioavailability of radiocesium during the first years after fallout rather than by radiocesium disappearing from the ecosystem. 38 refs., 3 figs., 2 tabs.

  11. Population Dynamics Of Earthworms In Cauvery Delta Areas In Relation To Soil Properties

    Directory of Open Access Journals (Sweden)

    K. Parthasarathi

    2013-11-01

    Full Text Available Population dynamics of earthworms in the two different cultivable land areas wet land cultivable areas (WLCA (including paddy, banana and sugarcane fields and dry land cultivable areas (DLCA (including coconut and groundnut fields of five different pedoecosystems in the Cauvery delta areas of Sirkazhi taluk, Nagapattinam district, Tamil Nadu state, India with reference to various soil ecological parameters have been studied, for the first time during the period from November 2011 to April 2012. The WLCA (paddy> sugarcane> banana fields harbor maximum population dynamics of earthworms whereas low in DLCA (groundnut> coconut fields. This may be due to presence of more edaphic factors - OC, N and moisture. Along with these, microorganisms as protein and N rich food support for earthworm growth and reproduction. They are involved synergistically influence the density and biomass of earthworm at maximum. In the five different pedoecosystems of Cauvery delta areas, only two types of soil namely clayloam and sandyloam are found and this variations are due to the nature of earlier agricultural activity and the nature of soil texture. Population dynamics of earthworm in different pedoecosystem are found in soil having 17.623.8% range of moisture and among pedoecosystems, more moisture content and more earthworm population dynamics are found in paddy field, followed by sugarcane, banana, groundnut and coconut field. This is due to adequate and frequent irrigation, more water holding capacity, higher microbial activity, OC, N and other nutrient content of the soil.

  12. Physical and chemical characterization of earthworms and humus obtained by vertical vermicomposting

    Directory of Open Access Journals (Sweden)

    Luclia Hoehne

    2013-01-01

    Full Text Available Earthworms culture are usually made horizontally and it is necessary a lot of area. In order to minimize the size of earthworms culture and the possibility to be applied in residences, this paper proposed evaluate conditions for vertical vermicomposting. For this, were purchased vertical boxes and organic matter. The earthworms of species Eisenia andrei, california red earthworms, were used. There were evaluated the adaptation of earthworms and physical and chemical characterization of the humus. Results showed that there was a good adaptation of earthworms in this configuration, minimizing the space required, and it is one technique for environmentally friendly recycling of organic waste, creating a bio-product wich can used as fertilizers.Resumo Minhocrios so normalmente feitoshorizontalmente sendo necessria uma rea grande. A fim de minimizar o tamanho da cultura de minhocas e a possibilidade de ser aplicado em residncias, este trabalho prope avaliar as condies de vermicompostagem vertical. Para isso, foram adquiridas caixas verticais e matria orgnica. Foram usadas minhocas da espcie Eisenia andrei, minhocas vermelhas da califrmia. Foi avaliada a adaptao das minhocas e caracterizao fsico-qumica do hmus gerado. Os resultados mostraram que houve uma boa adaptao das minhocas nesta configurao, minimizando o espao utilizado, e uma tcnica de reciclagem ecolgica de resduos orgnicos, a criao de umbioproduto o qual pode ser usado como adubo.

  13. Functional attributes: Compacting vs decompacting earthworms and influence on soil structure

    Directory of Open Access Journals (Sweden)

    Arnauth Martinez GUI, Yannick BAIDAI, Jrme Ebagnerin TONDOH,Jeroen HUISING

    2012-08-01

    Full Text Available A short term field mesocosm experiment was performed in semi-deciduous forest areas of Ivory Coast to assess the impact of a decompacting (Hyperiodrilus africanus, Eudrilidae and two compacting (Millsonia omodeoi and Dichogaster terraenigrae, Acanthodrilidae earthworm species on soil properties. These species have been selected for their predominance in the region and their contrasting impact on soil structure. The experimental design consisted of a treatment without worms (control, and treatments with one, two or three species of earthworms. Both compacting and decompacting earthworms increased water infiltration rate in all treatments, with marked impact in H. africanus and M. omodeoi+D. terraenigrae treatments. Interactions between compacting and decompacting species resulted in more large aggregates in comparison to when the compacting species D. terraenigrae was alone. This may be accounted for by their compacting attribute as compacting earthworms are responsible for producing the highest number of large aggregates. The low values of mean weight diameter in treatments combining decompacting and compacting earthworms compared with compacting "M. omodeoi" one also confirmed the trend of decline in soil compaction in the presence of the decompacting species. These results showed positive impact of species richness on soil structure regulation, which is crucial in ecosystem productivity and support consequently the insurance hypothesis. In fact, this study showed that the preservation of earthworm species belonging to these two contrasting functional groups is essential for the maintenance of stable soil structure regulation in agro-tropical ecosystems [Current Zoology 58 (4: 556565, 2012].

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

    Science.gov (United States)

    Fujii, Katsuhiko; Ikeda, Kana; Yoshida, Seo

    2012-09-01

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

  15. Invasive earthworms interact with abiotic conditions to influence the invasion of common buckthorn (Rhamnus cathartica).

    Science.gov (United States)

    Roth, Alexander M; Whitfeld, Timothy J S; Lodge, Alexandra G; Eisenhauer, Nico; Frelich, Lee E; Reich, Peter B

    2015-05-01

    Common buckthorn (Rhamnus cathartica L.) is one of the most abundant and ecologically harmful non-native plants in forests of the Upper Midwest United States. At the same time, European earthworms are invading previously glaciated areas in this region, with largely anecdotal evidence suggesting they compound the negative effects of buckthorn and influence the invasibility of these forests. Germination and seedling establishment are important control points for colonization by any species, and manipulation of the conditions influencing these life history stages may provide insight into why invasive species are successful in some environments and not others. Using a greenhouse microcosm experiment, we examined the effects of important biotic and abiotic factors on the germination and seedling establishment of common buckthorn. We manipulated light levels, leaf litter depth and earthworm presence to investigate the independent and interactive effects of these treatments on buckthorn establishment. We found that light and leaf litter depth were significant predictors of buckthorn germination but that the presence of earthworms was the most important factor; earthworms interacted with light and leaf litter to increase the number and biomass of buckthorn across all treatments. Path analysis suggested both direct and moisture-mediated indirect mechanisms controlled these processes. The results suggest that the action of earthworms may provide a pathway through which buckthorn invades forests of the Upper Midwest United States. Hence, researchers and managers should consider co-invasion of plants and earthworms when investigating invasibility and creating preemptive or post-invasion management plans. PMID:25481818

  16. Complete mitochondrial genome of four pheretimoid earthworms (Clitellata: Oligochaeta) and their phylogenetic reconstruction.

    Science.gov (United States)

    Zhang, Liangliang; Jiang, Jibao; Dong, Yan; Qiu, Jiangping

    2015-12-15

    Among oligochaetes, the Pheretima complex within the Megascolecidae is a major earthworm group. Recently, however, the systematics of the Pheretima complex based on morphology are challenged by molecular studies. Since little comparative analysis of earthworm complete mitochondrial genomes has been reported yet, we sequenced mitogenomes of four pheretimoid earthworm species to explore their phylogenetic relationships. The general earthworm genomic features are also found in four earthworms: all genes transcribed from the same strand, the same initiation codon ATG for each PCGs, and conserved structures of RNA genes. Interestingly we find an extra potential tRNA-leucine (CUN) in Amynthas longisiphonus. The earthworm mitochondrial ATP8 exhibits the highest evolutionary rate, while the gene CO1 evolves slowest. Phylogenetic analysis based on protein-coding genes (PCGs) strongly supports the monophyly of the Clitellata, Hirudinea, Oligochaeta, Megascolecidae and Pheretima complex. Our analysis, however, reveals non-monophyly within the genara Amynthas and Metaphire. Thus the generic divisions based on morphology in the Pheretima complex should be reconsidered. PMID:26291739

  17. Impact of land protection in soil quality properties and in earthworm biomass in Venezuelan savannas

    Scientific Electronic Library Online (English)

    D, Lpez-Hernndez; L, Hernndez; A, Ojeda; E, Quintero; S, Caipo.

    2014-12-01

    Full Text Available We studied soil parameters and the earthworm biomass and density in a protected savanna (PS) from fire and cattle raising for more than forty years located at Estacin Biolgica de los Llanos, Venezuela (EBLL), and an adjacent non-protected savanna (NS) under frequent burning and agricultural activi [...] ties, located less than 1 km apart. Earthworm sampling was carried out at the end of the dry season (April), and at the peak of the wet season (July-August) using a hand sorting extraction method. In each plot, five to seven sampling units were selected corresponding to soil monoliths of 25x25x30 cm. The main physical, chemical, microbial (biomass) and enzymatic activities of soils in both systems were estimated. Thepresence of an abundant litter layer under the tree canopies in the PS have increased the soil water retention capacity, the organic-C, C-microbial biomass, dehydrogenase activity and fertility levels respect NS. This may allow for an increase in the density and biomass of earthworms in the PS compared with the adjacent NS. The systems were characterized by abundance in juvenile individuals belonging to the Glossoscolecidae family; two different morphotypes of the genus Aicodrilus were registered. Earthworms found were located in an endo-anecic ecological category. Results suggest that, agricultural management in savannas by modification of physical and biochemical soil properties can decrease an important fraction of pedofauna, particularly their earthworm communities. However, earthworm populations and soil quality indicators can be restored after long-term protection.

  18. Earthworms as Ecosystem Engineers and the Most Important Detritivors in Forest Soils

    Directory of Open Access Journals (Sweden)

    Yahya Kooch

    2008-01-01

    Full Text Available Earthworms are considered as soil engineers because of their effects on soil properties and their influence on the availability of resources for other organisms, including microorganisms and plants. However, the links between their impacts on the soil environment and the resulting modification of natural selection pressures on engineer as well as on other organisms have received little attention. Earthworms are known to have a positive influence on the soil fabric and on the decomposition and mineralization of litter by breaking down organic matter and producing large amounts of fasces, thereby mixing litter with the mineral soil. Therefore, they play an important part in changes from one humus from to another according to forest succession patterns. Consequently, they are also expected to be good bio-indicators for forest site quality and are thus useful when planning forest production improvement. Earthworm`s populations are as indicator that in exploited regions is destruction indicator and reclamation plans is nature return indicator. In this study we summarized the current knowledge in relation to earthworm`s ecology in forest soils as ecosystem engineers.

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

    Science.gov (United States)

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

    1980-01-01

    (1) DDT, dieldrin, and heptachlor were each applied to separate replicate plots in a hay field at 0.6, 2.2, or 9.0 kg/ha. For 11 yr thereafter, soil and earthworms were analysed for residues. (2) The average ratios of residues in earthworms (dry weight) to residues in soil (dry weight) were: total DDT, 5; dieldrin, 8; and heptachlor epoxide, 10. The average time for the initial residues in soil to be reduced by 50% were: total DDT, 3.2 yr; dieldrin, 5.1 yr; and heptachlor epoxide, 3.2 yr. The corresponding times for residues in earthworms were: total DDT, 3.2 yr; dieldrin, 2.6 yr; and heptachlor epoxide, 3.0 yr. (3) DDE was most persistent, and in plots treated at 9.0 kg/ha its concentration remained constant at about 0.4 ppm in soil and about 7 ppm in earthworms. (4) When applied at 9.0 kg/ha, DDT accumulated in earthworms to concentrations (32 ppm) which laboratory studies have shown to be hazardous to some sensitive bird species. When heptachlor was applied at 2.2 or 9.0 kg/ha, heptachlor epoxide in earthworms reached concentrations (8 ppm) potentially hazardous to woodcock. Dieldrin remained at potentially hazardous concentrations (8 ppm) for 3 yr in plots treated with 2.2 kg/ha and for 11 yr in plots treated with 9.0 kg/ha.

  20. Modification of root density in pot experiments with two tropical earthworm species

    Directory of Open Access Journals (Sweden)

    George G. BROWN

    2010-01-01

    Full Text Available Three greenhouse experiments were performed to assess the role of two common tropical geophagous endogeic earthworm species, Pontoscolex corethrurus and Polypheretima elongata, on root density of several plant species in two soil types, a clayey Andosol and a sandy Alfisol, from Veracruz, Mexico. The equivalent of about 12 kg dry soil were placed into 20 l plastic pots and 3-14 individuals were inoculated to pots planted with common beans (Phaseolus vulgaris, Brachiaria decumbens pasture grass under four P fertilization regimes (0, 1.6, 8.4 and 10 kg P ha-1 and maize (Zea mays with or without surface residues. Pots received only one species of earthworms (either P. corethrurus or P. elon-gata. At harvest, the pots were cut in half and a transparent plastic sheet (overheads used to draw root and earthworm structures (burrows, casts in vertical and horizontal (every 5 cm planes. The drawings were scanned, binarized and submitted to image analysis techniques to determine the density of roots, casts and burrows. Root density was generally higher and there was a trend for more even distribution of roots in the soil, both horizontally and vertically, in the presence of earthworms. Nevertheless, few relationships were observed between root density and shoot biomass or the density of earthworm casts and burrows. A more diffuse (less aggregated root distribution due to earthworms may aid plants in resistance to stress, although the induced changes in the root system may not necessarily lead to greater yields

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

    International Nuclear Information System (INIS)

    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 (EC50 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. - Highlights: ? Reproductive endpoints were assessed for Eisenia fetida exposed to chlortectracyline (CTC). ? CTC may induce physiological and molecular responses in E. fetida. ? A clear relationship was observed between CTC doses and DNA damage of coelomocytes. - Chlortetracycline in soil could induce physiological responses and genotoxicity on earthworms at realistic environmental concentrations.

  2. Impact of land protection in soil quality properties and in earthworm biomass in Venezuelan savannas

    Scientific Electronic Library Online (English)

    D, Lpez-Hernndez; L, Hernndez; A, Ojeda; E, Quintero; S, Caipo.

    Full Text Available We studied soil parameters and the earthworm biomass and density in a protected savanna (PS) from fire and cattle raising for more than forty years located at Estacin Biolgica de los Llanos, Venezuela (EBLL), and an adjacent non-protected savanna (NS) under frequent burning and agricultural activi [...] ties, located less than 1 km apart. Earthworm sampling was carried out at the end of the dry season (April), and at the peak of the wet season (July-August) using a hand sorting extraction method. In each plot, five to seven sampling units were selected corresponding to soil monoliths of 25x25x30 cm. The main physical, chemical, microbial (biomass) and enzymatic activities of soils in both systems were estimated. Thepresence of an abundant litter layer under the tree canopies in the PS have increased the soil water retention capacity, the organic-C, C-microbial biomass, dehydrogenase activity and fertility levels respect NS. This may allow for an increase in the density and biomass of earthworms in the PS compared with the adjacent NS. The systems were characterized by abundance in juvenile individuals belonging to the Glossoscolecidae family; two different morphotypes of the genus Aicodrilus were registered. Earthworms found were located in an endo-anecic ecological category. Results suggest that, agricultural management in savannas by modification of physical and biochemical soil properties can decrease an important fraction of pedofauna, particularly their earthworm communities. However, earthworm populations and soil quality indicators can be restored after long-term protection.

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

    Energy Technology Data Exchange (ETDEWEB)

    Klobucar, Goeran I.V., E-mail: gklobuca@zg.biol.pmf.hr [Department of Zoology, Faculty of Science, University of Zagreb, Rooseveltov trg 6, 10000 Zagreb (Croatia); Stambuk, Anamaria; Srut, Maja [Department of Zoology, Faculty of Science, University of Zagreb, Rooseveltov trg 6, 10000 Zagreb (Croatia); Husnjak, Ivana [Ministry of Environmental Protection, Physical Planning and Construction, Ulica Republike Austrije 14, Zagreb (Croatia); Merkas, Martina [Croatian Institute for Brain Research, School of Medicine, University of Zagreb, Salata 12, 10000 Zagreb (Croatia); Traven, Luka [Department of Environmental Medicine, Medical Faculty, University of Rijeka, Brace Branchetta 20a, 51000 Rijeka (Croatia); Teaching Institute of Public Health of the Primorsko-goranska County, Kresimirova 52a, 51000 Rijeka (Croatia); Cvetkovic, Zelimira [Department of Ecology, Institute of Public Health, Mirogojska c. 16, 10000 Zagreb (Croatia)

    2011-04-15

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

  4. THE USE OF SELECTED ANAESTHETIC DRUGS IN SEARCH OF A METHOD FOR IMPROVING EARTHWORMS WELFARE

    Directory of Open Access Journals (Sweden)

    Agnieszka Podolak-Machowska

    2013-07-01

    Full Text Available This paper describes selected effects of body contact of earthworms Dendrobaena veneta Rosa with local anaesthetic (LA drugs used for human anesthesia (lidocaine and prilocaine and anaesthetics for aquatic animals (MS-222. The findings showed safe and effective immobilization of earthworms with prilocaine at a concentration of 0.25-1%. At the applied concentrations lidocaine was safe, but less effective. On the other hand, MS-222, at the applied concentrations had a strongly irritating effect for earthworms and induced convulsive body movements connected with a discharge of coelomic fluid. The results may be relevant both for improving the welfare of earthworms during experiments and for the organization of research involving testing drugs on invertebrates. In this case, by using earthworms as an experimental model and by applying the method for measuring their mobility after contact with anaesthetics, which has been described in this article, it might be possible to replace experiments on guinea pigs, rabbits, rats and mice, which are expensive and require an approval of an ethics committee, with laboratory tests on earthworms.

  5. Radiocesium (137Cs) from the Chernobyl reactor in Eurasian woodcock and earthworms in Norway

    International Nuclear Information System (INIS)

    To understand the ecological effects of the Chernobyl reactor accident, we investigated radiocesium (137Cs) levels in Eurasian woodcock (Scolopax rusticola), earthworms (Lambricidae), litter (dead organic materials lying on the ground), humus (beneath litter 2 cm deep), and mineral soil samples (3-6 cm deep) from a heavily effected (20-60 kBq/m2[1 Bq = 1 nuclear fission/sec]) area in Norway. The highest concentrations measured in earthworms (1988 median = 142 Bq/Kg) and woodcock (1986 median = 730 Bq/kg) for human food (600 Bq/kg fresh mass) only were found in woodcock during 1986. Radiocesium concentrations decreased (P < 0.001) in earthworms (40%) and woodcock (95%) from 1986 to 1990. There was no reduction in total radiocesium in soil over the same period. The relatively high radiocesium concentrations in woodcock during 1986 and the decreasing radiocesium ratio in woodcock to earthworms during the first years following fallout could have been caused by woodcock ingesting abiotic radiocesium with earthworms. The decrease in radiocesium in woodcock and earthworms during the study (1986-90) probably resulted from decreasing bioavailability of radiocesium during the first years after fallout rather than by radiocesium disappearing from the ecosystem. 38 refs., 3 figs., 2 tabs

  6. Hot big bang or slow freeze?

    International Nuclear Information System (INIS)

    We confront the big bang for the beginning of the universe with an equivalent picture of a slow freeze a very cold and slowly evolving universe. In the freeze picture the masses of elementary particles increase and the gravitational constant decreases with cosmic time, while the Newtonian attraction remains unchanged. The freeze and big bang pictures both describe the same observations or physical reality. We present a simple crossover model without a big bang singularity. In the infinite past spacetime is flat. Our model is compatible with present observations, describing the generation of primordial density fluctuations during inflation as well as the present transition to a dark energy-dominated universe

  7. Well-plate freeze-drying

    DEFF Research Database (Denmark)

    Trnka, Hjalte; Rantanen, Jukka; Grohganz, Holger

    2015-01-01

    Abstract Context: Freeze-drying in presence of excipients is a common practice to stabilize biomacromolecular formulations. The composition of this formulation is known to affect the quality of the final product. Objective: The aim of this study was to evaluate freeze-drying in well-plates as a...... no significant edge effect was found for any of the quality attributes analyzed. Conclusion: Freeze-drying in well-plates was found to be a suitable and representative high throughput platform for formulation screening....

  8. Earthworm invasion as the driving force behind plant invasion and community change in northeastern North American forests.

    Science.gov (United States)

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

    2009-08-01

    Identification of factors that drive changes in plant community structure and contribute to decline and endangerment of native plant species is essential to the development of appropriate management strategies. Introduced species are assumed to be driving causes of shifts in native plant communities, but unequivocal evidence supporting this view is frequently lacking. We measured native vegetation, non-native earthworm biomass, and leaf-litter volume in 15 forests in the presence and absence of 3 non-native plant species (Microstegium vimineum, Alliaria petiolata, Berberis thunbergii) to assess the general impact of non-native plant and earthworm invasions on native plant communities in northeastern United States. Non-native plant cover was positively correlated with total native plant cover and non-native earthworm biomass. Earthworm biomass was negatively associated with cover of native woody and most herbaceous plants and with litter volume. Graminoid cover was positively associated with non-native earthworm biomass and non-native plant cover. These earthworm-associated responses were detected at all sites despite differences in earthworm species and abundance, composition of the native plant community, identity of invasive plant species, and geographic region. These patterns suggest earthworm invasion, rather than non-native plant invasion, is the driving force behind changes in forest plant communities in northeastern North America, including declines in native plant species, and earthworm invasions appear to facilitate plant invasions in these forests. Thus, a focus on management of invasive plant species may be insufficient to protect northeastern forest understory species. PMID:19236448

  9. Stability of Freeze-Dried Lactobacillus acidophilus in Banana, Soybean and Pearl Barley Powders

    OpenAIRE

    Nathanon Trachoo; Panomkorn Wechakama; Anuchita Moongngarm; Maitree Suttajit

    2008-01-01

    Effect of banana, soybean, pearl barley powders and nonfat dry milk on the viability of freeze-dried Lactobacillus acidophilus at 4 and 25°C was studied during 30 days of storage. The survival of freeze-dried L. acidophilus at 4°C was greater than that at 25°C. The survival of L. acidophilus in banana, pearl barley, soybean powders and nonfat dry milk powder was higher than that in control (0.1% peptone water) at both temperatures indicating that addition of banana, soybean and pearl barley p...

  10. Evaluation of spin freezing versus conventional freezing as part of a continuous pharmaceutical freeze-drying concept for unit doses.

    Science.gov (United States)

    De Meyer, L; Van Bockstal, P-J; Corver, J; Vervaet, C; Remon, J P; De Beer, T

    2015-12-30

    Spin-freezing as alternative freezing approach was evaluated as part of an innovative continuous pharmaceutical freeze-drying concept for unit doses. The aim of this paper was to compare the sublimation rate of spin-frozen vials versus traditionally frozen vials in a batch freeze-dryer, and its impact on total drying time. Five different formulations, each having a different dry cake resistance, were tested. After freezing, the traditionally frozen vials were placed on the shelves while the spin-frozen vials were placed in aluminum vial holders providing radial energy supply during drying. Different primary drying conditions and chamber pressures were evaluated. After 2h of primary drying, the amount of sublimed ice was determined in each vial. Each formulation was monitored in-line using NIR spectroscopy during drying to determine the sublimation endpoint and the influence of drying conditions upon total drying time. For all tested formulations and applied freeze-drying conditions, there was a significant higher sublimation rate in the spin-frozen vials. This can be explained by the larger product surface and the lower importance of product resistance because of the much thinner product layers in the spin frozen vials. The in-line NIR measurements allowed evaluating the influence of applied drying conditions on the drying trajectories. PMID:25981618

  11. Earthworms newly from Mongolia (Oligochaeta,Lumbricidae, Eisenia

    Directory of Open Access Journals (Sweden)

    Robert Blakemore

    2013-04-01

    Full Text Available 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 E. 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 Bouch, 1972 synonym of the E. 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 E. nordenskioldi ssp. is appended.

  12. Further records of non-cryptic New Zealand earthworms

    Directory of Open Access Journals (Sweden)

    Robert Blakemore

    2011-12-01

    Full Text Available Current descriptions add natives Aporodrilus aotea sp. n., A. 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 N. equestris and holotypes of the other two are briefly redescribed. Whereas M. tasmani now belongs in Notoscolex Fletcher, 1887 and M. animae belongs in Anisochaeta Beddard, 1890, further lack of dorsal pores in N. equestris as with Notoscolex esculentus (Benham, 1904 and N. mortenseni (Michaelsen, 1924 newly qualifies all three as additional combs. novae in primarily Tasmanian genus Aporodrilus Blakemore, 2000.

  13. Escape and avoidance learning in the earthworm Eisenia hortensis

    Directory of Open Access Journals (Sweden)

    W. Jeffrey Wilson

    2014-01-01

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

  14. Snow Melting and Freezing on Older Townhouses

    DEFF Research Database (Denmark)

    Nielsen, Anker; Claesson, Johan

    2011-01-01

    The snowy winter of 2009/2010 in Scandinavia prompted many newspaper articles on icicles falling from buildings and the risk this presented for people walking below. The problem starts with snow melting on the roof due to heat loss from the building. Melt water runs down the roof and some of it...... will freeze on the overhang. The rest of the water will either run off or freeze in gutters and downpipes or turn into icicles. This paper describes use of a model for the melting and freezing of snow on roofs. Important parameters are roof length, overhang length, heat resistance of roof and overhang......, outdoor and indoor temperature, snow thickness and thermal conductivity. If the snow thickness is above a specific limit value the snow melting limit- some of the snow will melt. Another interesting limit value is the dripping limit. All the melt water will freeze on the overhang, if the snow thickness...

  15. Global Annual Freezing and Thawing Indices

    Data.gov (United States)

    National Aeronautics and Space Administration The total annual freezing and thawing indices are defined as the cumulative number of degree-days when air temperatures are below and above zero degrees Celsius....

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

    Science.gov (United States)

    Fernndez, Rosa; Novo, Marta; Marchn, Daniel F; Daz Cosn, Daro J

    2016-01-01

    Comparative phylogeography of widespread species that span the same geographic areas can elucidate the influence of historical events on current patterns of biodiversity, identify patterns of co-vicariance, and therefore aid the understanding of general evolutionary processes. Soil-dwelling animals present characteristics that make them suitable for testing the effect of the palaeogeographical events on their distribution and diversification, such as their low vagility and population structure. In this study, we shed light on the spatial lineage diversification and cladogenesis of two widely-distributed cosmopolitan and invasive earthworms (Aporrectodea rosea and A. trapezoides) in their putative ancestral area of origin, the Western Palearctic, and a few populations in North America. Molecular analyses were conducted on mitochondrial and nuclear markers from 220 (A. rosea) and 198 (A. trapezoides) individuals collected in 56 and 57 localities, respectively. We compared the lineage diversification pattern, genetic variability and cladogenesis in both species. Our findings showed that both species underwent a similar diversification from the Western Mediterranean plates to (i) Northern Europe and (ii) the Iberian Peninsula, establishing their two main lineages. Their diversification was in concordance with the main palaeogeographical events in the Iberian Peninsula and Western Mediterranean, followed by a later colonization of North America from individuals derived exclusively from the Eurosiberian lineage. Their diversification occurred at different times, with the diversification of A. rosea being potentially more ancient. Cladogenesis in both species seems to have been modelled only by the Mediterranean plate shifts, ignoring historical climatic oscillations such as the Messinian salinity crisis. Their high genetic variability, strong population structure, lack of gene flow and stepping-stone-like cladogenesis suggest the existence of different cryptic lineages. Our results may indicate a recurrent event in invasive earthworms within their ancestral distribution areas in the Western Palearctic. PMID:26299880

  17. Immersion freezing of birch pollen washing water

    OpenAIRE

    Augustin, S.; Hartmann, S.; B. Pummer; H. Grothe; D. Niedermeier; Clauss, T; Voigtlnder, J.; L. Tomsche; Wex, H; Stratmann, F

    2012-01-01

    In the present study, the immersion freezing behavior of birch pollen, i.e. its ice nucleating active (INA) macromolecules, was investigated at the Leipzig Aerosol Cloud Interaction Simulator (LACIS). For that, washing water of two different birch pollen samples with different regional origin (Northern birch and Southern birch) were used. The immersion freezing of droplets generated from the pollen washing water was already observed at temperatures higher than ?20 C, for bo...

  18. Periodic ice banding in freezing colloidal dispersions.

    Science.gov (United States)

    Anderson, Anthony M; Worster, M Grae

    2012-12-01

    Concentrated colloidal alumina dispersions were frozen in a directional solidification apparatus that provides independent control of the freezing rate and temperature gradient. Two distinct steady-state modes of periodic ice banding were observed in the range of freezing rates examined. For each mode, the wavelength between successive bands of segregated ice decreases with increasing freezing rate. At low freezing rates (0.25-3 ?m s(-1)), the ice segregates from the suspension into ice lenses, which are cracklike in appearance, and there is visible structure in the layer of rejected particles in the unfrozen region ahead of the ice lenses. In this regime, we argue that compressive cryosuction forces lead to the irreversible aggregation of the rejected particles into a close-packed cohesive layer. The temperature in the aggregated layer is depressed below the bulk freezing point by more than 2 C before the ice lenses are encountered; moreover, this undercooled region appears as a light-colored layer. The magnitude of the undercooling and the color change in this region both suggest the presence of pore ice and the formation of a frozen fringe. The possibility of a frozen fringe is supported by a quantitative model of the freezing behavior. At intermediate freezing rates, around 4 ?m s(-1), the pattern of ice segregation is disordered, coinciding with the disappearance of the dark- and light-colored layers. Finally, at high freezing rates (5-10 ?m s(-1)), there is a new mode of periodic ice banding that is no longer cracklike and is absent of any visible structure in the suspension ahead of the ice bands. We discuss the implications of our experimental findings for theories of ice lensing. PMID:23110707

  19. PCR-DGGE analysis of earthworm gut bacteria diversity in stress of Escherichia coli O157:H7

    OpenAIRE

    Zhenjun Sun; Yufeng Zhang; Hui Zhao; Yupeng Wu; Gaochan Wang; Yi (Leaf) Zhang

    2013-01-01

    In order to test if the intestinal bacteria play an important role in antibacterial ability of earthworm, we chose Escherichia coli O157:H7, an anthropozoonosis pathogen, as a biological stressor and studied the change of intestinal bacteria community of earthworm by PCR-DGGE analysis. Results showed that the pathogen merely existed 1 - 3 days, then almost disappeared after through the earthworms gut. In this period, the diversity and abundance index of intestinal bacteria increased first, ...

  20. Hydrocarbon exclusion from ground water during freezing

    International Nuclear Information System (INIS)

    Bench-scale studies were conducted using a constant-head ground-water flow chamber and natural soil. Initial experiments with chlorides and dye were conducted to test the hydraulic and adsorptive characteristics of the chamber. A constant flow of phenol was then introduced into the chamber and contaminant movement with time was monitored under freezing and nonfreezing conditions. The chamber was located in a controlled-temperature room, and freezing fronts were induced from the soil surface downward using cooled Freon circulated through freezer pads placed on the surface of the soil. The results conclusively demonstrate that phenol is excluded from the freezing front and pushed downward through the system. Extensive exclusion of the chemical occurs even though the freezing point of phenol (43 C) is significantly higher than water. The information gained through this research is applicable in cold regions outside Alaska and the Arctic where ground water systems may undergo periodic freezing, and may also be of extreme importance in artificial-freezing scenarios such as those currently being investigated by the Environmental Protection Agency (EPA) as a method of contaminant containment

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

    Science.gov (United States)

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

    2010-05-01

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

  2. Soil Aggregate Stability in the Presence of Earthworms (Lumbricus terrestris L. and Different Organic Materials in a Calcareous Soil

    Directory of Open Access Journals (Sweden)

    F. S. Moosavi

    2011-01-01

    Full Text Available Although the crucial function of earthworms in improvement of soil physical properties is well -know, but very little is known of the interactive influence of earthworms and organic materials on soil properties such as soil aggregate stability, particularly in arid and semi-arid soils. The low organic matter content and the significant role of earthworms in improving physical properties of arid and semi-arid soils necessitate studying the interactive effects of organic materials and earthworms. Thus, the main objective of this study was to identify the interactive effects of anecic earthworm (Lumbricus terrestris L. and various organic residues (including alfalfa, compost, mixture of alfalfa and compost and cow dung on soil aggregate stability expressed as the Mean Weight Diameter (MWD, Geometric Mean Diameter (GMD and Aggregation Ratio (AR, and furthermore soil Ca and Mg contents. The experiment consisted of a 25 factorial treatment organized in a completely randomized design with four replications under controlled greenhouse conditions, lasted for 150 days. Results showed that earthworm inoculation and organic materials addition alone increased significantly all the indices of soil aggregation and aggregate stability, and Ca and Mg contents. However, the combined use of earthworms and organic residues resulted in more stable aggregates. Results indicated that earthworm inoculation in the presence of organic materials resulted in 39, 58, 2, 67, 43 and 74% increases, respectively in MWD, AR, GMD, Ca, Mg and macroaggregates whereas microaggregates were reduced by 13.5% in earthworm-worked soils. We observed a significant relationship (R2=0.945 between soil Ca content and MWD, demonstrating that earthworms apparently excrete calcite that helps bonding clay particles and soil organic matter via cationic (Ca+2 bridging. In summary, results of this study show that the simultaneous applications of anecic earthworms and organic materials may considerably help in improving the structure of arid and semi-arid soils with low carbon level.

  3. Survival of Cold-Stressed Campylobacter jejuni on Ground Chicken and Chicken Skin during Frozen Storage

    OpenAIRE

    Bhaduri, Saumya; Cottrell, Bryan

    2004-01-01

    Campylobacter jejuni is prevalent in poultry, but the effect of combined refrigerated and frozen storage on its survival, conditions relevant to poultry processing and storage, has not been evaluated. Therefore, the effects of refrigeration at 4°C, freezing at −20°C, and a combination of refrigeration and freezing on the survival of C. jejuni in ground chicken and on chicken skin were examined. Samples were enumerated using tryptic soy agar containing sheep's blood and modified cefoperazone c...

  4. Saccharomyces cerevisiae glycerol/H+ symporter Stl1p is essential for cold/near-freeze and freeze stress adaptation. A simple recipe with high biotechnological potential is given

    Directory of Open Access Journals (Sweden)

    Ferreira Clia

    2010-11-01

    Full Text Available Abstract Background Freezing is an increasingly important means of preservation and storage of microbial strains used for many types of industrial applications including food processing. However, the yeast mechanisms of tolerance and sensitivity to freeze or near-freeze stress are still poorly understood. More knowledge on this regard would improve their biotechnological potential. Glycerol, in particular intracellular glycerol, has been assigned as a cryoprotectant, also important for cold/near-freeze stress adaptation. The S. cerevisiae glycerol active transporter Stl1p plays an important role on the fast accumulation of glycerol. This gene is expressed under gluconeogenic conditions, under osmotic shock and stress, as well as under high temperatures. Results We found that cells grown on STL1 induction medium (YPGE and subjected to cold/near-freeze stress, displayed an extremely high expression of this gene, also visible at glycerol/H+ symporter activity level. Under the same conditions, the strains harbouring this transporter accumulated more than 400 mM glycerol, whereas the glycerol/H+ symporter mutant presented less than 1 mM. Consistently, the strains able to accumulate glycerol survive 25-50% more than the stl1? mutant. Conclusions In this work, we report the contribution of the glycerol/H+ symporter Stl1p for the accumulation and maintenance of glycerol intracellular levels, and consequently cell survival at cold/near-freeze and freeze temperatures. These findings have a high biotechnological impact, as they show that any S. cerevisiae strain already in use can become more resistant to cold/freeze-thaw stress just by simply adding glycerol to the broth. The combination of low temperatures with extracellular glycerol will induce the transporter Stl1p. This solution avoids the use of transgenic strains, in particular in food industry.

  5. The identification of proteomic markers of sperm freezing resilience in ram seminal plasma.

    Science.gov (United States)

    Rickard, J P; Leahy, T; Soleilhavoup, C; Tsikis, G; Labas, V; Harichaux, G; Lynch, G W; Druart, X; de Graaf, S P

    2015-08-01

    The source and composition of seminal plasma has previously been shown to alter the ability of spermatozoa to survive cryopreservation. In the present study, the ionic and proteomic composition of seminal plasma from rams with high (HSP; n = 3) or low (LSP; n = 3) freezing resilient spermatozoa was assessed. 75 proteins were identified to be more abundant in HSP and 48 proteins were identified to be more abundant in LSP. Individual seminal plasma proteomes were established for each of the six rams examined. For each ram, correlations were conducted between previously recorded freezing resilience [1] and individual spectral counts in order to identify markers of freezing resilience. 26S proteasome complex, acylamino acid releasing enzyme, alpha mannosidase class 2C, heat shock protein 90, tripeptidyl-peptidase 2, TCP-1 complex, sorbitol dehydrogenase and transitional endoplasmic reticulum ATPase were found to be positively correlated (r(2) > 0.7) with freezing resilience. Cystatin, zinc-2-alpha glycoprotein, angiogenin-2-like protein, cartilage acidic protein-1, cathepsin B and ribonuclease 4 isoform 1 were found to be negatively correlated (r(2) > 0.7) with freezing resilience. Several negative markers were found to originate from the accessory sex glands, whereas many positive markers originated from spermatozoa and were part of or associated with the 26S proteasome or CCT complex. PMID:26025878

  6. Effect of acute gamma radiation and protective action of different concentration of extracts of safora japonica and hypericum perforatum on the life of aboriginal earthworms of Absheron

    International Nuclear Information System (INIS)

    Full text : As atomic power is increasingly recognized as a potential energy source to sustain future human development, radiological protection of the environment will become an even more important environmental safety concern. Thus, an understanding of the effects of ionizing radiation on non-human biota is required by the International Commission on Radiological Protection for the radiological protection of the environment. Soil processes are vital to sustainable terrestrial ecosystems, and soil invertebrates play an important role in nutrient cycling by feeding on microbiota. Because of their ecological importance, soil invertebrates are used for ecological impact assessments of terrestrial ecosystem pollutants. For chemical substances, single-species laboratory tests are used to understand toxicity. Standard tests using earthworms and spring tails have been developed by the Organization for Economic Co-operation and Development (OECD) and the International Organization for Standardization (ISO). Laboratory toxicity tests are also applicable in field contamination monitoring to determine if test organisms have been exposed to field-corrected soils. In such assays, gene expression as a biomarker has been receiving increased attention as it may produce fast, sensitive and diagnostic assays. A similar use of laboratory tests can be applied to assess the environmental impact of ionizing radiation. An understanding of the dose-effect relations of ionising radiation for non-human biota establishes important baselines for radiobiological protection of ecosystems. We used standard laboratory tests to examine dose-effect relationships of gamma radiation on the survival, biomass changing, feeding activity, coprolite excretion of aboriginal earthworms

  7. The anti-cell death FNK protein protects cells from death induced by freezing and thawing

    International Nuclear Information System (INIS)

    The FNK protein, constructed from anti-apoptotic Bcl-xL with enhanced activity, was fused with the protein transduction domain (PTD) of the HIV/Tat protein to mediate the delivery of FNK into cells. The fusion protein PTD-FNK was introduced into chondrocytes in isolated articular cartilage-bone sections, cultured neurons, and isolated bone marrow mononuclear cells to evaluate its ability to prevent cell death induced by freezing and thawing. PTD-FNK protected the cells from freeze-thaw damage in a concentration-dependent manner. Addition of PTD-FNK with conventional cryoprotectants (dimethyl sulfoxide and hydroxyethyl starch) increased surviving cell numbers around 2-fold compared with controls treated only with the cryoprotectants. Notably, PTD-FNK allowed CD34+ cells among bone marrow mononuclear cells to survive more efficiently (12-fold more than the control cells) from two successive freeze-thaw cycles. Thus, PTD-FNK prevented cell death induced by freezing and thawing, suggesting that it provides for the successful cryopreservation of biological materials

  8. A new freeze casting technique for ceramics

    Science.gov (United States)

    Araki, Kiyoshi

    A new freeze casting technique for ceramics capable of manufacturing near room temperature with a sublimable vehicle has been developed in order to eliminate expensive processes under extremely cold temperatures in the conventional freeze casting. Fluid concentrated slurries of Al2O 3 powder in molten camphene (C10H16) were successfully prepared at 55C with a small amount of a dispersant. These slurries were quickly solidified (frozen) at room temperature to yield a rigid solid green body, where the frozen camphene was easily removed by sublimation (freeze-drying) with negligible shrinkage. Sintering was successfully conducted without any special binder burnout process to yield dense sintered bodies (over 98% T.D). An organic alloy with a eutectic composition in the naphthalene (C 10H8)-camphor (C10H16O) binary system with a eutectic temperature of 31C was also found to be a successful vehicle for the new ceramic freeze casting. The fabrication processes are almost the same as those with camphene. It was found that vehicles with off-eutectic compositions resulted in large voids in the sintered body due to the ceramic particle rejection by pro-eutectic crystals during freezing. At the eutectic composition, fine lamellar microstructure in the solidified vehicle inhibits the particle rejection. The proposed advantages of the new freeze casting technique with a sublimable vehicle include; (1) elimination of extremely cold temperatures used in conventional freeze casting; (2) elimination of troublesome binder burnout process; and (3) fast manufacturing cycle due to quick solidification. Porous ceramic bodies with unique interconnected pore channels were fabricated by the new freeze casting with lower solid content. The unique channels surrounded by fully dense walls have nearly circular cross-sections unlike conventional aqueous freeze casting. The porosity and the channel diameters are controllable by the solid content in the slurry. The unique channels are replicas of entangled dendrites of frozen camphene, which sublimes during freeze-drying process. The unique porous structure with interconnected pore channels, which is completely new, is considered potentially useful in many applications such as filters and implantable bone scaffolds.

  9. Effects of freezing on soil temperature, freezing front propagation and moisture redistribution in peat: laboratory investigations

    Directory of Open Access Journals (Sweden)

    R. M. Nagare

    2012-02-01

    Full Text Available There are not many studies that report water movement in freezing peat. Soil column studies under controlled laboratory settings can help isolate and understand the effects of different factors controlling freezing of the active layer in organic covered permafrost terrain. In this study, four peat Mesocosms were subjected to temperature gradients by bringing the Mesocosm tops in contact with sub-zero air temperature while maintaining a continuously frozen layer at the bottom (proxy permafrost. Soil water movement towards the freezing front (from warmer to colder regions was inferred from soil freezing curves, liquid water content time series and from the total water content of frozen core samples collected at the end of freezing cycle. A substantial amount of water, enough to raise the upper surface of frozen saturated soil within 15 cm of the soil surface at the end of freezing period appeared to have moved upwards during freezing. Diffusion under moisture gradients and effects of temperature on soil matric potential, at least in the initial period, appear to drive such movement as seen from analysis of freezing curves. Freezing front (separation front between soil zones containing and free of ice propagation is controlled by latent heat for a long time during freezing. A simple conceptual model describing freezing of an organic active layer initially resembling a variable moisture landscape is proposed based upon the results of this study. The results of this study will help in understanding, and ultimately forecasting, the hydrologic response of wetland-dominated terrain underlain by discontinuous permafrost.

  10. Effects of spatial and temporal variation in metal availability on earthworms in floodplain soils of the river Dommel, The Netherlands

    Energy Technology Data Exchange (ETDEWEB)

    Bleeker, Eric A.J. [Department of Animal Ecology, Institute of Ecological Science, Vrije Universiteit, De Boelelaan 1085, 1081 HV Amsterdam (Netherlands)]. E-mail: eric.bleeker@falw.vu.nl; Gestel, Cornelis A.M. van [Department of Animal Ecology, Institute of Ecological Science, Vrije Universiteit, De Boelelaan 1085, 1081 HV Amsterdam (Netherlands)

    2007-08-15

    Regarding impact on ecological soil functioning, metal pollution is often considered a constant factor for certain sampling sites. However, especially bioavailable concentrations may differ in space and time. This aspect was investigated on four sites along a metal-polluted river, differing in soil characteristics and metal concentrations. Every four weeks earthworm densities, soil characteristics, and metal concentrations in soil and earthworms were determined. Earthworm biomass and density fluctuated in time and increased with increasing metal contamination, indicating the presence of compensating factors. Multivariate analysis suggested organic matter and moisture content to be the main factors explaining earthworm biomass. Metal concentrations in the earthworms increased with increasing total or 0.01 M CaCl{sub 2} extractable soil concentrations, but no time-related trends were seen. Cadmium concentrations in the earthworms exceeded background values, suggesting a potential risk. The neutral red retention biomarker assay, however, did not show any signs of metal stress in the earthworms. - Soil characteristics appear to dominate earthworm abundance and metal bioaccumulation in contaminated floodplain soils.

  11. Mutual impacts of wheat (Triticum aestivum L.) and earthworms (Eisenia fetida) on the bioavailability of perfluoroalkyl substances (PFASs) in soil

    International Nuclear Information System (INIS)

    Wheat and earthworms were exposed individually and together to soils contaminated with 11 perfluoroalkyl substances (PFASs). Wheat accumulated PFASs from soil with root concentration factors and bioconcentration factors that decreased as the number of perfluorinated carbons in the molecule increased. Earthworms accumulated PFASs from soil with biota-to-soil accumulation factors that increased with the number of carbons. Translocation factors (TF) of perfluorinated carboxylates (PFCAs) in wheat peaked at perfluorohexanoic acid and decreased significantly as the number of carbons increased or decreased. Perfluorohexane sulfonate produced the greatest TF of the three perfluorinated sulfonates (PFSAs) examined. Wheat increased the bioaccumulation of all 11 PFASs in earthworms and earthworms increased the bioaccumulation in wheat of PFCAs containing seven or less perfluorinated carbons, decreased bioaccumulation of PFCAs with more than seven carbons, and decreased bioaccumulation of PFSAs. In general, the co-presence of wheat and earthworms enhanced the bioavailability of PFASs in soil. -- Highlights: • PFASs can be taken up by root of wheat from soil and translocated to shoot. • The RCFs and BCFs of PFASs in wheat decreased with perfluorinated carbon chain length. • PFHxA had the highest TF, which decreased exponentially with the carbon chain length. • The BSAFs in earthworm increased with carbon chain length. • The co-presence of wheat and earthworm enhanced the bioavailability of PFASs in soil. -- PFASs can be uptake by root of wheat from soil and translocated to shoot and co-presence of wheat and earthworm enhance the bioavailability of PFASs in soil

  12. Effects of metal pollution on earthworm communities in a contaminated floodplain area: Linking biomarker, community and functional responses

    International Nuclear Information System (INIS)

    Effects on earthworms in the contaminated floodplain area the Biesbosch, the Netherlands, were determined at different levels of organization using a combination of field and laboratory tests. The species Lumbricus rubellus, collected from different polluted sites in the Biesbosch, showed reduced values for the biomarker neutral red retention time (NRRT), mainly explained by high metal concentrations in the soil and the resulting high internal copper concentrations in the earthworms. Organic pollutant levels in earthworms were low and did not explain reduced NRRTs. Earthworm abundance and biomass were not correlated with pollutant levels in the soil. Litterbag decomposition and bait-lamina feeding activity, measures of the functional role of earthworms, were not affected by metal pollution and did not show any correlation with metal concentrations in soil or earthworms nor with NRRT. Effects at the biochemical level therefore did not result in a reduced functioning of earthworm communities. - Metal pollution in floodplain soils does affect earthworm biomarker response but not their activity in decomposition processes

  13. Impact of the earthworm Lumbricus terrestris (L.) on As, Cu, Pb and Zn mobility and speciation in contaminated soils

    International Nuclear Information System (INIS)

    To assess the risks that contaminated soils pose to the environment properly a greater understanding of how soil biota influence the mobility of metal(loid)s in soils is required. Lumbricus terrestris L. were incubated in three soils contaminated with As, Cu, Pb and Zn. The concentration and speciation of metal(loid)s in pore waters and the mobility and partitioning in casts were compared with earthworm-free soil. Generally the concentrations of water extractable metal(loid)s in earthworm casts were greater than in earthworm-free soil. The impact of the earthworms on concentration and speciation in pore waters was soil and metal specific and could be explained either by earthworm induced changes in soil pH or soluble organic carbon. The mobilisation of metal(loid)s in the environment by earthworm activity may allow for leaching or uptake into biota. - Research highlights: ? Earthworms increase the mobility and availability of metals and metalloids in soils. ? We incubated L. terrestris in three soils contaminated with As, Cu, Pb and Zn. ? Earthworms increased the mobility of As, Cu, Pb and Zn in their casts. ? The mechanisms for this could be explained by changes in pH or organic carbon. - Lumbricus terrestris change the partitioning of metal(loid)s between soil constituents and increase the mobility of metal(loid)s in casts and pore water.

  14. Assessing soil ecotoxicity of methyl tert-butyl ether using earthworm bioassay; closed soil microcosm test for volatile organic compounds

    International Nuclear Information System (INIS)

    An earthworm bioassay was conducted to assess ecotoxicity in methyl tert-butyl ether (MTBE)-amended soils. Ecotoxicity of MTBE to earthworms was evaluated by a paper contact method, natural field soil test, and an OECD artificial soil test. All tests were conducted in closed systems to prevent volatilization of MTBE out of test units. Test earthworm species were Perionyx excavatus and Eisenia andrei. Mortality and abnormal morphology of earthworms exposed to different concentrations of MTBE were examined. MTBE was toxic to both earthworm species and the severity of response increased with increasing MTBE concentrations. Perionyx excavatus was more sensitive to MTBE than Eisenia andrei in filter papers and two different types of soils. MTBE toxicity was more severe in OECD artificial soils than in field soils, possibly due to the burrowing behavior of earthworms into artificial soils. The present study demonstrated that ecotoxicity of volatile organic compounds such as MTBE can be assessed using an earthworm bioassay in closed soil microcosm with short-term exposure duration. - Earthworm bioassay can be a good protocol to assess soil ecotoxicity of volatile organic compounds such as MTBE

  15. Impact of the earthworm Lumbricus terrestris (L.) on As, Cu, Pb and Zn mobility and speciation in contaminated soils

    Energy Technology Data Exchange (ETDEWEB)

    Sizmur, Tom, E-mail: t.p.sizmur@reading.ac.uk [Soil Research Centre, Department of Geography and Environmental Science, School of Human and Environmental Sciences, University of Reading, Whiteknights, Reading RG6 6DW (United Kingdom); Palumbo-Roe, Barbara; Watts, Michael J. [British Geological Survey, Kingsley Dunham Centre, Keyworth, Nottingham NG12 5GG (United Kingdom); Hodson, Mark E. [Soil Research Centre, Department of Geography and Environmental Science, School of Human and Environmental Sciences, University of Reading, Whiteknights, Reading RG6 6DW (United Kingdom)

    2011-03-15

    To assess the risks that contaminated soils pose to the environment properly a greater understanding of how soil biota influence the mobility of metal(loid)s in soils is required. Lumbricus terrestris L. were incubated in three soils contaminated with As, Cu, Pb and Zn. The concentration and speciation of metal(loid)s in pore waters and the mobility and partitioning in casts were compared with earthworm-free soil. Generally the concentrations of water extractable metal(loid)s in earthworm casts were greater than in earthworm-free soil. The impact of the earthworms on concentration and speciation in pore waters was soil and metal specific and could be explained either by earthworm induced changes in soil pH or soluble organic carbon. The mobilisation of metal(loid)s in the environment by earthworm activity may allow for leaching or uptake into biota. - Research highlights: > Earthworms increase the mobility and availability of metals and metalloids in soils. > We incubated L. terrestris in three soils contaminated with As, Cu, Pb and Zn. > Earthworms increased the mobility of As, Cu, Pb and Zn in their casts. > The mechanisms for this could be explained by changes in pH or organic carbon. - Lumbricus terrestris change the partitioning of metal(loid)s between soil constituents and increase the mobility of metal(loid)s in casts and pore water.

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

    International Nuclear Information System (INIS)

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

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

    Science.gov (United States)

    Top, Sara; Filley, Timothy

    2010-05-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, T.V.; Chang, L.W.; Smith, M.K.; Daniel, F.B. [Environmental Protection Agency, Cincinnati, OH (United States); Wiechman, B. [Pathology Associates, Inc., West Chester, OH (United States); Reddy, G. [USABRDL, Fort Detrick, MD (United States)

    1994-12-31

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

  19. Earthworms and structure rehabilitation in subsoils and in topsoils affected by opencast mining for coal

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, V.I.; Scullion, J.; Salih, R.O.; Al-Bakri, K.H.

    1988-01-01

    Because soil structure seems to benefit from the period under grass in a normal rotation, it is widely assumed that grass roots are primarily responsible (Strutt, 1970). Due credit is also given to efficient drainage, adequate inputs of organic matter, lime and microbial activity. However, it is not clear whether the earthworm is a passive exploiter or a causal agent of structure improvement. When the pressures of production end up in severe soil structure deterioration, or when massive soil disturbance, and stockpiling ends up in soils restored with little residual structure, experimental evidence suggests that the role of the earthworm is crucial. Evidence will be presented to show how earthworms, in association with all the other factors normally held to be responsible, initiate the development of water-stable, soil granulation. However, evidence will also be presented which shows how certain features of modern agriculture are, to some extent at least, antagonistic to earthworms. In utilizing degraded land, it may be necessary to farm initially for the benefit of the earthworm rather than for yield. This approach must be maintained despite the fact that, in the early stages, it may result in a phase of greater waterlogging and susceptibility to poaching. 30 refs., 4 figs., 1 tab.

  20. Biomarker responses in earthworms (Eisenia fetida) to soils contaminated with di-n-butyl phthalates.

    Science.gov (United States)

    Du, Li; Li, Guangde; Liu, Mingming; Li, Yanqiang; Yin, Suzhen; Zhao, Jie

    2015-03-01

    Di-n-butyl phthalates (DBP) are recognized as ubiquitous contaminants in soil and adversely impact the health of organisms. Changes in the activity of antioxidant enzymes and levels of glutathione-S-transferase (GST), glutathione (GSH), and malondialdehyde (MDA) were used as biomarkers to evaluate the impact of DBP on earthworms (Eisenia fetida) after exposure to DBP for 28days. DBP was added to artificial soil in the amounts of 0, 5, 10, 50, and 100mgkg(-1) of soil. Earthworm tissues exposed to each treatment were collected on the 7th, 14th, 21st, and 28th day of the treatment. We found that superoxide dismutase (SOD) and catalase (CAT) levels were significantly inhibited in the 100mgkg(-1) treatment group on day 28. After 21days of treatment, GST activity in 10-50mgkg(-1) treatment groups was markedly stimulated compared to the control group. MDA content in treatment groups was higher than in the control group throughout the exposure time, suggesting that DBP may lead to lipid peroxidation (LPO) in cells. GSH content increased in the treatment group that received 50mgkg(-1) DBP from 7days of exposure to 28days. These results suggest that DBP induces serious oxidative damage on earthworms and induce the formation of reactive oxygen species (ROS) in earthworms. However, DBP concentration in current agricultural soil in China will not constitute any threat to the earthworm or other animals in the soil. PMID:25328097

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

    International Nuclear Information System (INIS)

    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. Highlights: Cu markedly increased the weight loss ratio of earthworm. Cu decreased the cocoon production of earthworm. The toxicity of GPS on earthworm was insignificant. The presence of GPS could reduce the toxicity of Cu on earthworm. -- The presence of glyphosate could reduce the toxicity and bioavailability of Cu in the soil because of its strong chelating effects

  2. Bioaccumulation of perfluoroalkyl carboxylates (PFCAs) and perfluoroalkane sulfonates (PFSAs) by earthworms (Eisenia fetida) in soil

    International Nuclear Information System (INIS)

    Earthworms were exposed to artificially contaminated soils with ten perfluoroalkyl substances (PFASs). PFASs with longer perfluorinated carbon chain displayed higher uptake rate coefficients (ku), longer half-life (t1/2) and time to steady-state (tss) but lower elimination rate coefficients (ke) than the shorter ones. Similarly, perfluorosulfonates acids (PFSAs) displayed higher ku, longer t1/2 and tss but lower ke than perflurocarboxylic acids (PFCAs) with the same perfluorinated chain length. All the studied PFASs, including those with seven or less perfluorinated carbons, were bioaccumulated in the earthworms and the biota-to-soil accumulation factors (BSAFs) increased with perfluorinated carbon chain length and were greater for PFSAs than for PFCAs of equal perfluoroalkyl chain length. The BSAFs were found to be dependent on the concentrations of PFASs in soil and decreased as the level of PFASs in soil increased. -- Highlights: •PFASs with seven or less perfluoroalkyl carbons were bioaccumulated in earthworm. •The BSAFs of PFASs in earthworm increased with perfluoroalkyl chain length. •The BSAFs of PFSAs were greater than PFCAs of equal perfluoroalkyl chain length. •The ku increased with perfluorinated chain length while ke decreased. •The BSAFs of PFASs decreased as their concentrations in soil increased. -- Perfluoroalkyl substances (PFASs) can be effectively bioaccumulated in earthworms including those with seven or less perfluoroalkyl carbon chain length

  3. Engineering of Soil Biological Quality from Nickel Mining Stockpile Using Two Earthworm Ecological Groups

    Directory of Open Access Journals (Sweden)

    L M H Kilowasid

    2015-04-01

    Full Text Available Earthworms have the ability in modifying soil biological quality for plant growth. Their ability is mostly depending on its ecological groups. The objectives of the research were to study the influence of two ecological groups of earthworms on soil microbial activity and soil micro-fauna abundance, and to know the potential of soil modified by earthworms as plant growth medium. Eight combination of individual earthworm from epigeic and endogeic groups was applied into pot that was filled by soil from two years of nickel stockpile and each treatment was repeated by five times. The experiment was following complete randomize design procedure. After sixteen days of research, the soil sample from each pot was analyzed for soil FDA activity, number of flagellate and nematodes. Furthermore, one kg of the soil from each pot was taken and every pot was grown by Paraserianthes falcataria seedling with the age of five days and continued its growth for two months. The results indicated that the soil FDA activity, number of flagellate and nematodes among treatments were significantly differences. In addition, it indicated the significant differences in dry weight of shoot, root, total plant, and root to shoot ratio of P. falcataria seedlings. It concluded that the combination of an individual number of epigeic and endogeic earthworms improved soil biological quality of stock pile, amd most suitable for seedlings growth in nickel mining area.

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

    Science.gov (United States)

    Ci?erci, ?brahim Hakk?; Ali, Muhammad Muddassir; Kayg?s?z, ?hret Yksek; Liman, Recep

    2016-02-01

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

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

    Science.gov (United States)

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

    1999-01-01

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

  6. [Single and binary-combined toxicity of methamidophos, acetochlor and Cu on earthworm Eisenia foetida].

    Science.gov (United States)

    Liang, Jidong; Zhou, Qixing

    2003-04-01

    A population of earthworm Eisenia foetida was exposed to single and binary-combined contamination of phaeozem by methamidophos, acetochlor and Cu. The result showed that one of three test chemicals had its toxicity on the earthworm population, and the single toxic sequence of the chemicals was acetochlor > methamidophos > Cu. The values of their LD50 were 0.307, 0.708 and 118.70 mg.kg-1, respectively. The difference was depended on the biological mechanisms of the earthworm population. Acetochlor and Cu in soil could be absorbed by the earthworm population through penetrating through the skin of an earthworm. The result also showed that Cu could swell the toxicity of methamidophos, whether it was in low or high concentration by the binary-combined toxic effect test. Cu in low concentration could decrease the toxicity of acetochlor, but in high concentration, Cu could increase the acetochlor toxicity in soil. Therefore, these three pollutants were dangerous to the ecological security of soil ecosystem and soil-health quality. Furthermore, when the chemicals in same soil environment act one another, they could boost up the potential danger of soil ecosystem contaminated by the three pollutants. The joint toxic effects of various chemicals were in relation to their different concentration combinations in soil. PMID:12920910

  7. Role of Earthworms in Soil Fertility Maintenance through the Production of Biogenic Structures

    International Nuclear Information System (INIS)

    The soil biota benefits soil productivity and contributes to the sustainable function of all ecosystems. The cycling of nutrients is a critical function that is essential to life on earth. Earthworms (EWs) are a major component of soil fauna communities in most ecosystems and comprise a large proportion of macro fauna biomass. Their activity is beneficial because it can enhance soil nutrient cycling through the rapid incorporation of detritus into mineral soils. In addition to this mixing effect, mucus production associated with water excretion in earthworm guts also enhances the activity of other beneficial soil microorganisms. This is followed by the production of organic matter. So, in the short term, a more significant effect is the concentration of large quantities of nutrients (N, P, K, and Ca) that are easily assimilable by plants in fresh cast depositions. In addition, earthworms seem to accelerate the mineralization as well as the turnover of soil organic matter. Earthworms are known also to increase nitrogen mineralization, through direct and indirect effects on the microbial community. The increased transfer of organic C and N into soil aggregates indicates the potential for earthworms to facilitate soil organic matter stabilization and accumulation in agricultural systems, and that their influence depends greatly on differences in land management practices. This paper summarises information on published data on the described subjects.

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

    Science.gov (United States)

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

    2016-04-01

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

  9. Survival Analysis

    CERN Document Server

    Miller, Rupert G

    2011-01-01

    A concise summary of the statistical methods used in the analysis of survival data with censoring. Emphasizes recently developed nonparametric techniques. Outlines methods in detail and illustrates them with actual data. Discusses the theory behind each method. Includes numerous worked problems and numerical exercises.

  10. An Investigation into the Anti-microbial and Anti-fungal Properties of Earthworm Powder Obtained from Eisenia fetida

    Directory of Open Access Journals (Sweden)

    Abdullah Adil Ansari

    2011-01-01

    Full Text Available Present study was carried out during the year 2006-2007 on dried earthworm powder collected from culture of Eisenia fetida in vermicomposting units and focused on the effect of the dried earthworm on microbes determining the anti-microbial and anti-fungal properties of the worms, as well as the chemical composition of worms obtain from vermicomposting units. The earthworm powder was also subjected to analysis of nitrogen and potassium using standard procedures. Antimicrobial disc diffusion suspecting tests were carried out against Bacteria (Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa as well as the fungus Candida albicans with the following treatments: Control, earthworm powder in water (1:1, earthworm powder in water (1:2 and earthworm powder in acetone (1:2. The technique involves using disk diffusion susceptibility testing where disks from both the pure and diluted honey as well as the antibiotic disk erythromycin (control were impregnated onto the surface of the Mueller Hinton agar. The study conclusively proved that the earthworm powder (all dilutions has antifungal properties which would be effective in treating fungal infections, such as candidosis whereas did not indicate the anti-microbial properties which may be attributed to different composition of elements in earthworm powder obtained from vermicomposting unit rather than garden soil. ANOVA analysis (Single factor at p = 0.05, proved that differences between the different concentrations of earthworm powder treatment containing colonies of C. albicans was significant, indicating the effect of earthworm powder by inhibiting the growth of the fungus C. albicans.

  11. Droplet coalescence and freezing on hydrophilic, hydrophobic, and biphilic surfaces

    Science.gov (United States)

    Van Dyke, Alexander S.; Collard, Diane; Derby, Melanie M.; Betz, Amy Rachel

    2015-10-01

    Frost and ice formation can have severe negative consequences, such as aircraft safety and reliability. At atmospheric pressure, water heterogeneously condenses and then freezes at low temperatures. To alter this freezing process, this research examines the effects of biphilic surfaces (surfaces which combine hydrophilic and hydrophobic regions) on heterogeneous water nucleation, growth, and freezing. Silicon wafers were coated with a self-assembled monolayer and patterned to create biphilic surfaces. Samples were placed on a freezing stage in an environmental chamber at atmospheric pressure, at a temperature of 295 K, and relative humidities of 30%, 60%, and 75%. Biphilic surfaces had a significant effect on droplet dynamics and freezing behavior. The addition of biphilic patterns decreased the temperature required for freezing by 6 K. Biphilic surfaces also changed the size and number of droplets on a surface at freezing and delayed the time required for a surface to freeze. The main mechanism affecting freezing characteristics was the coalescence behavior.

  12. Hot big bang or slow freeze?

    Directory of Open Access Journals (Sweden)

    C. Wetterich

    2014-09-01

    Full Text Available We confront the big bang for the beginning of the universe with an equivalent picture of a slow freeze a very cold and slowly evolving universe. In the freeze picture the masses of elementary particles increase and the gravitational constant decreases with cosmic time, while the Newtonian attraction remains unchanged. The freeze and big bang pictures both describe the same observations or physical reality. We present a simple crossover model without a big bang singularity. In the infinite past spacetime is flat. Our model is compatible with present observations, describing the generation of primordial density fluctuations during inflation as well as the present transition to a dark energy-dominated universe.

  13. Heat transfer coefficient of cryotop during freezing.

    Science.gov (United States)

    Li, W J; Zhou, X L; Wang, H S; Liu, B L; Dai, J J

    2013-01-01

    Cryotop is an efficient vitrification method for cryopreservation of oocytes. It has been widely used owing to its simple operation and high freezing rate. Recently, the heat transfer performance of cryotop was studied by numerical simulation in several studies. However, the range of heat transfer coefficient in the simulation is uncertain. In this study, the heat transfer coefficient for cryotop during freezing process was analyzed. The cooling rates of 40 percent ethylene glycol (EG) droplet in cryotop during freezing were measured by ultra-fast measurement system and calculated by numerical simulation at different value of heat transfer coefficient. Compared with the results obtained by two methods, the range of the heat transfer coefficient necessary for the numerical simulation of cryotop was determined, which is between 9000 W/(m(2)K) and 10000 W/(m (2)K). PMID:23812315

  14. UltraViolet Freeze-in

    CERN Document Server

    Elahi, Fatemeh; Unwin, James

    2014-01-01

    If dark matter is thermally decoupled from the visible sector, the observed relic density can potentially be obtained via freeze-in production of dark matter. Typically in such models it is assumed that the dark matter is connected to the thermal bath through feeble renormalisable interactions. Here, rather, we consider the case in which the hidden and visible sectors are coupled only via non-renormalisable operators. This is arguably a more generic realisation of the dark matter freeze-in scenario, as it does not require the introduction of diminutive renormalisable couplings. We examine general aspects of freeze-in via non-renormalisable operators in a number of toy models and present several motivated implementations in the context of Beyond the Standard Model physics. Specifically, we study models related to the Peccei-Quinn mechanism and Z' portals.

  15. DNA Repair Inhibition by Mercuric Chloride in Earthworms after Exposure to Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Tae Ho; Kim, Jin Kyu [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Nili, Mohammad [Dawnesh Radiation Research Institute, Barcelona (Spain); An, Kwang Guk [Chungnam National University, Daejeon (Korea, Republic of)

    2011-10-15

    All organisms are being exposed to harmful factors present in the environment. Ionizing radiation can damage DNA through a series of molecular events depending on the radiation energy. The biological effects due to the combined action of ionizing radiation with the other factor are hard to estimate and predict in advance. Recently International Commission on Radiological Protection (ICRP) requires the effect data of ionizing radiation on non-human biota for the radiological protection of the environment. Earthworms have been identified by the ICRP as one of the reference animals and plants to be used in environmental radiation protection. Particularly, the earthworm Eisenia fetida can be used as a bio-indicator of pollution in soil. This study was performed to investigate the acute genotoxic effects of radiation and the synergistic effects between radiation and mercury in earthworm, E. fetida

  16. Modelling the accumulation of hydrophobic organic chemicals in earthworms. Application of the equilibrium partitioning theory

    Energy Technology Data Exchange (ETDEWEB)

    Belfroid, A.C. [Research Inst. of Toxicology, Univ. Utrecht (Netherlands); Seinen, W. [Dept. of Ecology and Ecotoxicology, Vrije Univ., Amsterdam (Netherlands); Gestel, K.C.A.M. van [Research Inst. of Toxicology, Univ. Utrecht (Netherlands); Hermens, J.L.M. [Research Inst. of Toxicology, Univ. Utrecht (Netherlands); Leeuwen, K.J. van [Research Inst. of Toxicology, Univ. Utrecht (Netherlands)

    1995-07-01

    In this paper a method is developed which can be used to estimate the body burden of organic hydrophobic chemicals in earthworms. In contrast to the equilibrium partitioning theory, two routes of uptake are incorporated: uptake from interstitial water and dietary uptake. Although many uncertainties still remain, calculations show that for earthworms steady state body burdens are mainly determined by uptake from interstitial water. Under most circumstances, the contribution of dietary uptake is small, except for hydrophobic chemicals (log K{sub OW}>5) in soils with a high organic matter (OM) content of {approx}20%. Under those conditions, estimates of the steady state body burden calculated with the equilibrium partitioning model, in which only uptake from interstitial water is taken into account, might result in a small underestimation of the real body burden of chemicals in earthworms. (orig.)

  17. Soil physical ambient and its relation ships with the earthworm's biomass in some Colombian Andean hillsides

    International Nuclear Information System (INIS)

    The work presented here describes on the one hand the relationship between diversity, density and biomass of the earthworm's side and humidity, total porosity and resistance to penetration in the hillsides soils (secondary forest, Inceptisol and Pennsisetum clandestinum pastured, Andisol) on the other hand side. Results indicate that there were significant differences between sites for density and biomass of earthworms, and that their presence was affected by the physical parameters. Resistance to soil penetrability and humidity were significantly different only in the first 20 cm; while in deeper soil layers these were no such difference between sites, this is of importance, since the surface of the soil suffers changes due to the management, thus affecting the conditions that regulate the earthworm populations

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

    Science.gov (United States)

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

    2013-05-01

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

  19. Bioaccumulation and biological effects in the earthworm Eisenia fetida exposed to natural and depleted uranium

    Energy Technology Data Exchange (ETDEWEB)

    Giovanetti, Anna, E-mail: anna.giovanetti@enea.i [ENEA, Institute of Radiation Protection, CR Casaccia Via Anguillarese 301, 00123 Rome (Italy); Fesenko, Sergey [International Atomic Energy Agency (IAEA), Agency' s Laboratories Seibersdorf, A-2444 Seibersdorf (Austria); Cozzella, Maria L. [ENEA, National Institute for Metrology of Ionizing Radiation, CR Casaccia Via Anguillarese 301, 00123 Rome (Italy); Asencio, Lisbet D. [Centro de Estudios Ambientales, Carretera a Castillo de Jagua, CP. 59350 C. Nuclear, Cienfuegos (Cuba); Sansone, Umberto [International Atomic Energy Agency (IAEA), Agency' s Laboratories Seibersdorf, A-2444 Seibersdorf (Austria)

    2010-06-15

    The accumulations of both natural (U) and depleted (DU) uranium in the earthworms (Eisenia fetida) were studied to evaluate corresponding biological effects. Concentrations of metals in the experimental soil ranged from 1.86 to 600 mg kg{sup -1}. Five biological endpoints: mortality, animals' weight increasing, lysosomal membrane stability by measuring the neutral red retention time (the NRRT), histological changes and genetic effects (Comet assay) were used to evaluate biological effects in the earthworms after 7 and 28 days of exposure. No effects have been observed in terms of mortality or weight reduction. Cytotoxic and genetic effects were identified at quite low U concentrations. For some of these endpoints, in particular for genetic effects, the dose (U concentration)-effect relationships have been found to be non-linear. The results have also shown a statistically significant higher level of impact on the earthworms exposed to natural U compared to depleted U.

  20. Associations between soil texture, soil water characteristics and earthworm populations of grassland

    DEFF Research Database (Denmark)

    Holmstrup, Martin; Lamand, Mathieu; Torp, Sren Bent; Labouriau, Rodrigo; Greve, Mogens Humlekrog; Heckrath, Goswin

    2011-01-01

    types of Denmark. Eleven earthworm species were found, but populations were mainly dominated by Aporrectodea tuberculata and A. longa. Despite considerable variation in soil parameters across the five study sites the results suggest that the biomass of anecic worms (or A. longa as a species) was not......The aim of the present study was to investigate the relationships between soil physical characteristics and earthworms in a regional-scale field study in Denmark. The earthworm populations along within-field gradients in soil texture were quantified at five field sites, representing dominant soil...... causally associated with the soil parameters studied. This indicates that there must be other causal factors associated with the abundance (and composition) of anecic worms that are not among the soil texture and structure parameters studied. On the other hand, soil texture (Coarse sand) was associated...

  1. Unitarity constraints on asymmetric freeze-in

    CERN Document Server

    Hook, Anson

    2011-01-01

    This paper considers unitarity and CPT constraints on asymmetric freeze-in, the use of freeze-in to store baryon number in a dark sector. In this scenario, Sakharov's out of equilibrium condition is satisfied by placing the visible and hidden sectors at different temperatures while a net visible baryon number is produced by storing negative baryon number in a dark sector. It is shown that unitarity and CPT lead to unexpected cancellations. In particular, the transfer of baryon number cancels completely at leading order.

  2. Reproducing Black's experiments: freezing point depression and supercooling of water

    International Nuclear Information System (INIS)

    We carried out two historical experiments referred to by Joseph Black, one on freezing mixtures of salted water with ice and another on freezing supercooled pure water by a small disturbance. The results confirm thermodynamical predictions for the depression of the freezing point of salted water and for the latent heat of freezing of supercooled water respectively, which came after Black. The depression of the freezing point can hardly be fitted in the framework of the caloric theory of heat, which was taken for granted by Black, and the instantaneous freezing of supercooled water also poses some difficulties for that theory. (author)

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

    Science.gov (United States)

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

    2013-08-01

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

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

    Science.gov (United States)

    de Andra, Mara M; Papini, Solange

    2005-01-01

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

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

    Science.gov (United States)

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

    2010-05-01

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

  6. Unravelling some Kinki earthworms (Annelida: Oligochaeta: Megadrili: Megascolecidae - Part II

    Directory of Open Access Journals (Sweden)

    Blakemore, R.J.

    2010-10-01

    Full Text Available Metaphire tanbode sp. nov. is found in rice paddy in Kinki plain at Lake Biwa and Amynthas yamade sp. nov. isfrom Hira range to the West. M. tanbode belongs to the M. hilgendorfi / A. tokioensis species-complex, while montane A. yamadeis comparable to both Amynthas aeruginosus-group and Duplodicodrilus schmardae-group. Genetic barcoding (mtDNA COI viatypes is attempted. Taxonomic housekeeping requires replacement of invalid homonyms: e.g. Pheretima montana Ishizuka, 1999(non type-species P. montana Kinberg, 1867 is renamed Amynthas nonmontanus; others are A. nonsilvestris, A. noninvisus, A.nonmonticolus and A. nonsetosus, noms. et combs. novae. Thus Pheretima Kinberg, 1867 s. stricto remains unrecorded from Japanwhile prior Amynthas Kinberg, 1867, and its derivative Metaphire Sims & Easton, 1972, are abundant and diverse. Family andgeneric level definition and placement of Oriental pheretimoids are restated for the benefit of current workers and for novicefield-ecologists. Surveys of below-ground biodiversity of rice paddy in Lake Biwa is compared to more natural habitats aroundLake Pedder in Western Tasmanian Wilderness Area, and co-incidentally, both have 21 recorded earthworm species. Thus claimsfrom various countries of less than six species per location are contraindicated by thorough eco-taxonomic methods yieldingmore representative results.

  7. Snakes mimic earthworms: propulsion using rectilinear travelling waves

    Science.gov (United States)

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

    2013-01-01

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

  8. Preservation of functionality of Bifidobacterium animalis subsp. lactis INL1 after incorporation of freeze-dried cells into different food matrices.

    Science.gov (United States)

    Vinderola, G; Zacaras, M F; Bockelmann, W; Neve, H; Reinheimer, J; Heller, K J

    2012-05-01

    The aim of this work was to investigate how production and freeze-drying conditions of Bifidobacterium animalis subsp. lactis INL1, a probiotic strain isolated from breast milk, affected its survival and resistance to simulated gastric digestion during storage in food matrices. The determination of the resistance of bifidobacteria to simulated gastric digestion was useful for unveiling differences in cell sensitivity to varying conditions during biomass production, freeze-drying and incorporation of the strain into food products. These findings show that bifidobacteria can become sensitive to technological variables (biomass production, freeze-drying and the food matrix) without this fact being evidenced by plate counts. PMID:22265312

  9. The influence of freezing rates on bovine pericardium tissue Freeze-drying

    Scientific Electronic Library Online (English)

    Camila Figueiredo, Borgognoni; Virgilio, Tattini Junior; Ana Maria Irene Bartolomeu, Ayrosa; Bronislaw, Polakiewicz; Adolfo Alberto, Leirner; Marina Junko Shiotsu, Maizato; Olga Zazuco, Higa; Marisa Masumi, Beppu; Ronaldo Nogueira de Moraes, Pitombo.

    2009-12-01

    Full Text Available O pericrdio bovino um material utilizado na fabricao de bioprteses. A liofilizao um mtodo de secagem que vem sendo estudado para a conservao de vlvulas cardacas. A preservao das caractersticas do biomaterial de fundamental importncia no bom funcionamento das vlvulas. Este artig [...] o a primeira etapa do desenvolvimento do ciclo de liofilizao do pericrdio bovino. Liofilizao o processo de secagem no qual a gua removida do material congelado por sublimao e desoro da gua incongelvel, sob presso reduzida. O congelamento influencia o tamanho do cristal de gelo e, consequentemente, a secagem primria e secundria. O objetivo deste estudo foi verificar a influncia das taxas de congelamento nos parmetros de liofilizao do pericrdio bovino. Determinou-se a temperatura de transio vtrea e o comportamento estrutural do pericrdio bovino liofilizado. Determinou-se o tempo da secagem primria e secundria. O protocolo de liofilizao utilizando-se congelamento lento com annealing apresentou os melhores resultados. Abstract in english The bovine pericardium has been used as biomaterial in developing bioprostheses. Freeze-drying is a drying process that could be used for heart valve's preservation. The maintenance of the characteristics of the biomaterial is important for a good heart valve performance. This paper describes the in [...] itial step in the development of a bovine pericardium tissue freeze-drying to be used in heart valves. Freeze-drying involves three steps: freezing, primary drying and secondary drying. The freezing step influences the ice crystal size and, consequently, the primary and secondary drying stages. The aim of this work was to investigate the influence of freezing rates on the bovine pericardium tissue freeze-drying parameters. The glass transition temperature and the structural behaviour of the lyophilized tissues were determined as also primary and secondary drying time. The slow freezing with thermal treatment presented better results than the other freeze-drying protocols.

  10. Study of Genital Variations among the Earthworms of Genus Pheretima Inhabiting the Soil of Islamabad

    Directory of Open Access Journals (Sweden)

    Ambreen Faiz

    2004-01-01

    Full Text Available External genital markings are supposed to be the key character of speciation and slight variation leads towards the differentiation among individuals of the same species. Such striking variations exist in the genital papillae of earthworms of genus Pheretima. This study was based on the exploration of soils of Islamabad to hunt the variations in number and position of genital papillae of earthworms belonging to genus Pheretima. A total of ten new variants were found, that were previously undescribed, including six variants of P. posthuma, three of P. morrisi and one of P. hawayana

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

    Science.gov (United States)

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

    2013-07-01

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

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

    Science.gov (United States)

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

    2015-04-01

    Earthworms can strongly activate microorganisms, increase microbial and enzyme activities and consequently the turnover of native soil organic matter. In extremely dynamic microhabitats and hotspots as biopores made by earthworms, the in situ enzyme activities are a footprint of complex biotic interactions. The effect of earthworms on the alteration of enzyme activities inside biopores and the difference between bio-pores and earthworm-free soil was visualized by in situ soil zymography (Spohn and Kuzyakov, 2014). For the first time, we prepared quantitative imaging of enzyme activities in biopores. Furthermore, we developed the zymography technique by direct application of a substrate saturated membrane to the soil to obtain better spatial resolution. Lumbricus terrestris L. was placed into transparent box (152015cm). Simultaneously, maize seed was sown in the soil. Control soil box with maize and without earthworm was prepared in the same way. After two weeks when bio-pore systems were formed by earthworm, we visualized in situ enzyme activities of five hydrolytic enzymes (?-glucosidase, cellobiohydrolase, chitinase, xylanase, leucine aminopeptidase) and phosphatase. Followed by non-destructive zymography, biopore samples and control soil were destructively collected to assay enzyme kinetics by fluorogenically labeled substrates method. Zymography showed higher activity of ?-glucosidase, chitinase, xylanase and phosphatase in biopores comparing to bulk soil. These differences were further confirmed by fluorimetric microplate enzyme assay detected significant difference of Vmax in four above mentioned enzymes. Vmax of ?-glucosidase, chitinase, xylanase and phosphatase in biopores is 68%, 108%, 50% and 49% higher than that of control soil. However, no difference in cellobiohydrolase and leucine aminopeptidase kinetics between biopores and control soil were detected. This indicated little effect of earthworms on protein and cellulose transformation in soil. In conclusion, earthworms contribute to the decomposition of carbohydrates through promoting enzyme activities involved in the C-cycle except for leucine aminopeptidase and cellobiohydrolase. References Spohn M, Kuzyakov Y. (2014) Spatial and temporal dynamics of hotspots of enzyme activity in soil as affected by living and dead roots - a soil zymography analysis, Plant Soil 379: 67-77

  13. Inhibitory of Encapsulated Earthworm Extract (Lumbricus rubellus on Pathogenic Bacteria in Vitro

    Directory of Open Access Journals (Sweden)

    L. Istiqomah

    2012-04-01

    Full Text Available The objective of this study was to determine the inhibitory of earthworm (Lumbricus rubellus extract (ECT and encapsulated earthworm extract (ECT-t as poultry feed additive against some pathogenic bacteria. Earthwom extract was prepared by dekokta method with water at 90 C then encapsulated by spray drying with maltodextrin as filler. In vitro antibacterial activity was performed using dilution method against Escherichia coli, Staphylococcus aureus, Salmonella pullorum, and Pseudomonas aeruginosa. The optical density results showed that started from ECT level 0.26% inhibited (P0.05 of ECT and ECT-t against S. pullorum.

  14. The Earthworm Gut: an Ideal Habitat for Ingested N2O-Producing Microorganisms

    OpenAIRE

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

    2003-01-01

    The in vivo production of nitrous oxide (N2O) by earthworms is due to their gut microbiota, and it is hypothesized that the microenvironment of the gut activates ingested N2O-producing soil bacteria. In situ measurement of N2O and O2 with microsensors demonstrated that the earthworm gut is anoxic and the site of N2O production. The gut had a pH of 6.9 and an average water content of approximately 50%. The water content within the gut decreased from the anterior end to the posterior end. In co...

  15. Freeze block testing of buried waste lines

    International Nuclear Information System (INIS)

    An investigation was conducted to demonstrate application of freeze blocking in waste transfer lines such that a hydrostatic pressure test can be applied. A shop test was conducted on a 20-foot length, 3-inch schedule 40, carbon steel pipe using a coolant of dry ice and Freon. The positive results from these tests prompted a similar employment of the freeze block method in hydrostatic pressure testing the feed inlet leading to 241-S-101 Waste Tank. This pipeline is a 3-inch schedule 10, stainless steel pipe approximately 800 feet long. The freeze block was formed near the lower end of the pipe as it entered the 101-S Waste Tank and a pressure hold test was applied to this pipeline. This test proved the integrity of the pipeline in question, and demonstrated the validity of freeze blocking an open-ended pipeline which could not be hydrotested in other conventional ways. The field demonstration facility, costing $30,200 was completed late in 1975

  16. Unitarity Constraints on Asymmetric Freeze-In

    Energy Technology Data Exchange (ETDEWEB)

    Hook, Anson; /SLAC

    2011-08-15

    This paper considers unitarity and CPT constraints on asymmetric freeze-in, the use of freeze-in to store baryon number in a dark sector. In this scenario, Sakharov's out of equilibrium condition is satisfied by placing the visible and hidden sectors at different temperatures while a net visible baryon number is produced by storing negative baryon number in a dark sector. It is shown that unitarity and CPT lead to unexpected cancellations. In particular, the transfer of baryon number cancels completely at leading order. This note has shown that if two sectors are in thermal equilibrium with themselves, but not with each other, then the leading effect transferring conserved quantities between the two sectors is of order the the weak coupling connecting them to the third power. When freeze-in is used to produce a net baryon number density, the leading order effect comes from {Omicron}({lambda}{sup 3}) diagrams where the intermediate state that goes on-shell has a different visible baryon number than the final state visible baryon number. Models in which the correct baryon number is generated with freeze-in as the dominant source of abundance, typically require {lambda} {approx}> 10{sup -6} and m{sub bath} {approx}> TeV. m{sub bath} is the mass of the visible particle which communicates with the hidden sector. The lower window is potentially observable at the LHC.

  17. Renormalization, Freezing Phase Transitions and Fibonacci Quasicrystals

    OpenAIRE

    Bruin, Henk; Leplaideur, Renaud

    2013-01-01

    We examine the renormalization operator determined by the Fibonacci substitution. We exhibit a fixed point and determine its stable leaf (under iteration of the operator). Then, we study the thermodynamic formalism for po- tentials in this stable leaf, and prove they have a freezing phase transition, with ground state supported on the attracting quasi-crystal associated to the Fibonacci substitution

  18. Unitarity Constraints on Asymmetric Freeze-In

    International Nuclear Information System (INIS)

    This paper considers unitarity and CPT constraints on asymmetric freeze-in, the use of freeze-in to store baryon number in a dark sector. In this scenario, Sakharov's out of equilibrium condition is satisfied by placing the visible and hidden sectors at different temperatures while a net visible baryon number is produced by storing negative baryon number in a dark sector. It is shown that unitarity and CPT lead to unexpected cancellations. In particular, the transfer of baryon number cancels completely at leading order. This note has shown that if two sectors are in thermal equilibrium with themselves, but not with each other, then the leading effect transferring conserved quantities between the two sectors is of order the the weak coupling connecting them to the third power. When freeze-in is used to produce a net baryon number density, the leading order effect comes from ?(?3) diagrams where the intermediate state that goes on-shell has a different visible baryon number than the final state visible baryon number. Models in which the correct baryon number is generated with freeze-in as the dominant source of abundance, typically require ? ?> 10-6 and mbath ?> TeV. mbath is the mass of the visible particle which communicates with the hidden sector. The lower window is potentially observable at the LHC.

  19. Effectivity of the Earthworms Pheretima hupiensis, Eudrellus sp. and Lumbricus sp. on the Organic Matter Decomposition Process

    Directory of Open Access Journals (Sweden)

    Ea Kosman Anwar

    2009-05-01

    Full Text Available The earthworms are the one of soil fauna component in soil ecosystem have an important role in organic matter decomposition procces. The earthworm feed plant leaf and plant matter up to apart and dissolved. Earthworm metabolisms produce like faeces that mixed with decomposed organic matter mean vermicompost. The vermicompost fertility varies because of some kind of earthworm differ in “niche” and attitude. The experiment was to study the effectivity of earthworm on organic matter decomposition which has been conducted in Soil Biological and Healthy Laboratory and Green House of Soil Research Institute Bogor, during 2006 Budget Year. The three kind of earthworms i.e Pheretima hupiensis, Lumbricus sp. and Eudrellus sp. combined with three kind of organic matter sources i.e rice straw, trash and palm oil plant waste (compost heap. The result shows that the Lumbricus sp. are the most effective decomposer compared to Pheretima hupiensis and Eudrellus sp. and the organic matter decomposed by Lumbricus sp. as followed: market waste was decomposed of 100%, palm oil empty fruit bunch (compost heap 95.8 % and rice straw 84.9%, respectively. Earthworm effectively decreased Fe, Al, Mn, Cu dan Zn.

  20. Uptake and retention of radio-caesium in earthworms cultured in soil contaminated by the Fukushima nuclear power plant accident.

    Science.gov (United States)

    Fujiwara, K; Takahashi, T; Nguyen, P; Kubota, Y; Gamou, S; Sakurai, S; Takahashi, S

    2015-01-01

    To understand the effects of radionuclides on non-human biota and the environment, it is essential to study the intake and metabolism of radio-isotopes in earthworms which are among the most important soil organisms, and Eisenia fetida, which were used in this study, are known to be sufficiently sensitive to chemicals and representative of common earthworms. In this study, we assessed the concentration ratios, uptake and retention, absorbed dose rate, and distribution of radio-caesium in earthworms. The concentration ratios of (137)Cs (i.e., the concentrations of radio-caesium in earthworms relative to those in dry soil) were higher early in the culturing period and decreased gradually over the experimental period. (137)Cs taken up by E.fetida was cleared rapidly after the worms were cultured in radio-caesium-free soil, suggesting that the metabolism of radio-caesium in earthworms is very rapid. Autoradiography demonstrated that the concentration of radio-caesium within the digestive tract was as high as that in the soil, while radio-caesium in the body tissue was lower than radio-caesium in the soil and was almost uniformly distributed among earthworm tissues. The highest absorbed dose rate of total exposure to radio-caesium ((137)Cs+(134)Cs) was calculated to be 1.9נ10(3) (?Gy/day) in the earthworms. PMID:25464049

  1. Surviving Objects

    OpenAIRE

    Murjas, Teresa

    2012-01-01

    Surviving Objects (2012) is a devised multi-media practice-as-research performance based on extensive interviews conducted with my elderly mother and recorded on a hand-held device. Our conversations concern her experiences as a child refugee following violent deportation by the Soviet Army from Eastern Poland to Siberia (1941), and her subsequent route, via Persia, to a British-run refugee camp in Northern Rhodesia, where she remained for 6 years before arriving in the UK. In order to aid my...

  2. Application of Pb isotopes to track the sources and routes of metal uptake in the earthworm Eisenia fetida

    Directory of Open Access Journals (Sweden)

    Bader Albogami

    2014-12-01

    Full Text Available The aim of this work is to determine the important routes of metal uptake in earthworms to enable a better understanding of the primary source of metal uptake in the environment. Earthworms can take up chemicals from pore water and soil both by ingestion and through contact with their skin. However, it is unclear which pathway is the most important for metal uptake. An experiment was designed in which both soil chemistry and foods were artificially manipulated, producing different pools of soil lead (Pb with different isotope compositions at a range of Pb concentrations. Earthworms (Eiseniafetida were exposed to different lead concentrations through the addition of 500 mg/kg lead oxide (Pb3O4 to soil and 500 mg/kg lead nitrate to food (manure, with distinctly different isotopic compositions. Earthworms were also exposed to combinations of soil only and soil plus food in order to quantify the proportions of Pb taken up from each component. After acid digestion of the earthworm tissues, the Pb isotope composition of the accumulated lead in the earthworms was measured using a Thermo-fisher, iCAPQ, ICP-MS for 208Pb/206Pb and 207Pb/206Pb ratios measured relative to NIST SRM 981, allowing us to determine the pathway of lead uptake. Mixing calculations have been used to deconvolute the lead isotope signatures and identify the amount of lead taken up by the earthworms from the different soil pools. Differences in bioaccumulation factors and the relative amounts of lead accumulated from different pools changes as a function of concentration in the different pools. Earthworms were shown to uptake lead from bothsoil and food sources through ingestion route. Our findings suggest that a major pathway of lead uptake in earthworm species is heavily influenced by their ecology.

  3. Radiocesium concentrations in epigeic earthworms at various distances from the Fukushima Nuclear Power Plant 6 months after the 2011 accident

    International Nuclear Information System (INIS)

    We investigated the concentrations of radiocesium in epigeic earthworms, litter, and soil samples collected from forests in Fukushima Prefecture 6 months after the Fukushima Dai-ichi Nuclear Power Plant accident in 2011. Radiocesium concentrations in litter accumulated on the forest floor were higher than those in the soil (05 cm depth). The highest average 134+137Cs concentrations in earthworms (approximately 19 Bq g?1 of wet weight with gut contents and 108 Bq g?1 of dry weight without gut contents) were recorded from a plot that experienced an air dose rate of 3.1 ?Sv h?1, and earthworm concentrations were found to increase with litter and/or soil concentrations. Average 134Cs and 137Cs concentrations (with or without gut contents) were intermediate between accumulated litter and soil. Different species in the same ecological groups on the same plots had similar concentrations because of their use of the same habitats or their similar physiological characteristics. The contribution of global fallout 137Cs to earthworms with gut contents was calculated to be very low, and most 137Cs in earthworms was derived from the Fukushima accident. Transfer factors from accumulated litter to earthworms, based on their dry weights, ranged from 0.21 to 0.35, in agreement with previous field studies. -- Highlights: Radiocesium concentrations in earthworms were intermediate between litter and soil. Three earthworm species in epigeic groups had similar radiocesium concentrations. Transfer factors from accumulated litter to earthworms ranged from 0.21 to 0.35

  4. Determining the bioavailability and toxicity of lead contamination to earthworms requires using a combination of physicochemical and biological methods

    International Nuclear Information System (INIS)

    This study aimed at assessing the bioavailability and toxicity of lead to Eisenia andrei in shooting range soils representing different land uses (forest, grassland, bullet plot). Soils contained 472398 mg Pb/kg dry weight (dw), but also had different pH-CaCl2 (3.26.8) and organic matter contents (3.813%). Therefore artificial soils with different pH and organic matter contents and two natural soils were included as control soils. Earthworms were exposed for 28 days and toxicity and uptake of Pb were related to total, water and 0.01 M CaCl2 extractable and porewater Pb concentrations as well as to soil characteristics. Pb uptake in the earthworms linearly increased with increasing soil concentrations. At >2000 mg Pb/kg dw and pH 3.33.5, high earthworm mortality with significant weight loss and complete inhibition of reproduction were recorded. At <1000 mg/kg dw, earthworm reproduction was more related to differences in pH and other soil characteristics than to Pb. -- Highlights: Availability and earthworm toxicity of Pb determined in field-contaminated soils. Earthworm toxicity of most-polluted soils explained from available Pb levels. Earthworm response in less polluted soils mainly determined by soil pH. Earthworm toxicity correlated with Pb uptake from the soil. Soil properties explained differences in earthworm Pb uptake and effects. -- Combination of physicochemical and biological assays helped explaining Pb toxicity in shooting range soils from available Pb concentrations and soil characteristics

  5. The hyphae of Uromyces appendiculatus within the leaf tissue after high pressure freezing and freeze substitution

    OpenAIRE

    Welter, Klaus; Mller, M.; Mendgen, Kurt

    1988-01-01

    The fine structure of the intercellular dikaryotic hyphae of the biotrophic fungus Uromyces appendiculatus was studied. High pressure freezing and freeze substitution were used to achieve a closer approximation of the native state than with conventional fixation and dehydration techniques. In addition to organelles previously described in rust fungi, heavily decorated multivesicular bodies (star bodies) were found close to the nuclei. Two types of tubular-vesicular complexes were distributed...

  6. Production of freeze-dried yeast culture for the brewing of traditional sorghum beer, tchapalo.

    Science.gov (United States)

    N'Guessan, Florent K; Coulibaly, Hermann W; Alloue-Boraud, Mireille W A; Cot, Marlne; Dj, Koffi Marcellin

    2016-01-01

    Freeze-drying is a well-known dehydration method widely used to preserve microorganisms. In order to produce freeze-dried yeast starter culture for the brewing purpose of African sorghum beer, we tested protective agents (sucrose, glucose, glycerol) in combination with support materials (millet, maize, sorghum, and cassava flours) at 1:1 ratio (v/v). The yeast strains Saccharomyces cerevisiae F 12-7 and Candida tropicalis C 0-7 previously isolated from sorghum beer were used in a mixed culture at a ratio of 2:1 (C.tropicalis/S.cerevisiae). After the freeze-drying, the residual water contents were between 0.78 -2.27%, 0.55 -4.09%, and 0.40-2.61%, respectively, with sucrose, glucose and glycerol. The dried yeasts viabilities were between 4.0% and 10.6%. Among the protective agents used, sucrose was found to be the best protectant giving cell viabilities of 8.4-10.6%. Considering the support materials, millet flour was the best support after drying. When the freeze-dried yeast powders were stored at 4C and room temperature (25-28C) for up to 3months, the survival rates were the highest with cassava flour as the support material. PMID:26788308

  7. Media alternatives for the collection, culture and freezing of mouse and cattle embryos.

    Science.gov (United States)

    Palasz, A T; Tornesi, M B; Archer, J; Mapletoft, R J

    1995-10-01

    The replacement of biological products in media for the collection, culture and freezing of mammalian embryos was studied. To test the hypothesis that chemically defined surfactants can replace bovine serum albumin (BSA) or serum in embryo media, morula-stage mouse and cattle embryos were collected, cultured, and/or frozen in the surfactant compound, VF5. Collection efficiency of mouse and cattle embryos did not differ whether the medium contained serum or surfactant. In addition, morula-stage mouse and cattle embryos developed and hatched at similar rates in culture media containing either BSA or surfactant. Although the freeze/thaw survival and development in culture of bovine embryos was not significantly different in any of the media, there was a significantly lower hatching rate of mouse embryos frozen with serum or surfactant than with cryoprotectant alone or with cryoprotectant plus albumin-free serum. However, the absence of serum or surfactant in embryo freezing media resulted in embryo loss, presumably due to stickiness. The data suggest that serum can be replaced by a chemically defined surfactant in mouse and cattle embryo transfer systems for the collection, culturing and freezing of embryos. It is likely that the beneficial effects of serum are due to its surfactant properties. PMID:16727768

  8. Effect of Glycerol, as Cryoprotectant in the Encapsulation and Freeze Drying of Microspheres Containing Probiotic Cells

    Directory of Open Access Journals (Sweden)

    Oana Lelia Pop

    2015-05-01

    Full Text Available It is reported that probiotics provide several health benefits as they help in maintaining a good balance and composition of intestinal flora, and increase the resistance against invasion of pathogens. Ensuring adequate dosages of probiotics at the time of consumption is a challenge, because several factors during processing and storage affect the viability of probiotic organisms. Major emphasis has been given to protect the microorganisms with the help of encapsulation technique, by addition of different protectants. In this study, probiotic cells (Bifidobacterium lactis 300B were entrapped in alginate/pullulan microspheres. In the encapsulation formula glycerol was used as cryoprotectant in the freeze drying process for long time storage. It was observed that the survival of Bifidobacterium lactis 300B when encapsulated without cryoprotectant was higher than the formula with glycerol in the fresh obtained microspheres. The addition of glycerol was in order to reduce the deep freezing and freeze drying damages. In the chosen formulations, glycerol did not proved protection for the entrapped probiotic cells in the freeze drying process, for which the use of glycerol as cryoprotectant for alginate/pullulan Bifidobacterium lactis 300B entrapment is not recommended.

  9. Evidence of membrane damage in Lactobacillus bulgaricus following freeze drying

    OpenAIRE

    Castro, H. P.; Teixeira, P. M.; Kirby, R.

    1997-01-01

    The mechanism of inactivation of Lactobacillus bulgaricus due to freeze drying was investigated. Cells were freeze-dried in skim milk powder, maltodextrin, glycerol, trehalose and water. Results are presented confirming previous authorsobservations regarding membrane damage during freeze drying. In an attempt to define more clearly the nature of this damage, further experiments were carried out. Results show that following freeze drying changes occur in the unsaturated: saturated fatty acid ...

  10. Does Anxiety Cause Freezing of Gait in Parkinson's Disease?

    OpenAIRE

    Ehgoetz Martens, Kaylena A; Ellard, Colin G.; Almeida, Quincy J.

    2014-01-01

    Individuals with Parkinson's disease (PD) commonly experience freezing of gait under time constraints, in narrow spaces, and in the dark. One commonality between these different situations is that they may all provoke anxiety, yet anxiety has never been directly examined as a cause of FOG. In this study, virtual reality was used to induce anxiety and evaluate whether it directly causes FOG. Fourteen patients with PD and freezing of gait (Freezers) and 17 PD without freezing of gait (Non-Freez...

  11. N2O-Producing Microorganisms in the Gut of the Earthworm Aporrectodea caliginosa Are Indicative of Ingested Soil Bacteria

    OpenAIRE

    Ihssen, Julian; Horn, Marcus A.; Matthies, Carola; Gner, Anita; Schramm, Andreas; Drake, Harold L.

    2003-01-01

    The main objectives of this study were (i) to determine if gut wall-associated microorganisms are responsible for the capacity of earthworms to emit nitrous oxide (N2O) and (ii) to characterize the N2O-producing bacteria of the earthworm gut. The production of N2O in the gut of garden soil earthworms (Aporrectodea caliginosa) was mostly associated with the gut contents rather than the gut wall. Under anoxic conditions, nitrite and N2O were transient products when supplemental nitrate was redu...

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

    Science.gov (United States)

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

    2011-12-01

    Many biotic and abiotic disturbances have shaped the structure of the deciduous forests in the Mid-Atlantic region. One major anthropogenic factor is land use history. Agricultural practices in the past undoubtedly facilitated non-native earthworm colonization and establishment. Today most secondary forests are dominated by European lumbricid earthworms, although native species also occur in some habitats. To investigate how earthworm community composition and abundance affect belowground processes and tree seedling growth we set up a field manipulation experiment at the Smithsonian Environmental Research Center in Edgewater, MD. A total of 66 experimental plots were set up in successional (70 yrs) and mature (150 yrs) Tulip-poplar-Oak associations. We manipulated earthworm abundance and leaf litter input, and planted seedlings of Tulip poplar, Red maple, Red oak, and American beech. The experiment lasted for two years during which we regularly monitored density, biomass and species composition of earthworm assemblages and measured soil respiration. Soil moisture, temperature and air temperature were also continuously monitored using a wireless sensor network. At harvest, soil bulk density, pH, N pools, C:N ratio, potential N-mineralization rates, and enzyme activity were determined. We used quantitative PCR to assess the community composition of soil fungi. We also determined the extent of mycorrhizal colonization and biomass of roots, shoots and leaves. We conducted likelihood ratio tests for random and fixed effects based on mixed model analyses of variance. Differences between soil depths and among sites and plots accounted for a large portion of the variation in many soil properties. Litter quality affected soil pH and N mineralization. Earthworm densities affected bulk density, inorganic N content, and N mineralization. Both mycorrhizal groups were more abundant in mature than in successional forests. Both ectomycorrhizal (ECM) and arbuscular (AM) fungi were less abundant in the earthworm removal plots. There was a significant positive earthworm effect on the rate and thermal sensitivity of soil respiration. Soil respiration was consistently higher in plots with tulip poplar litter than those with beech litter, indicating a strong influence of plant residue quality. However, the differences were smaller in the second year than in the first one indicating an adaptation of the soil system. Oak and beech seedlings were smaller in high density earthworm plots, while the reverse was true for maple and tulip poplar seedlings. Non-native earthworms affect below- and aboveground processes, however, these effects depend on forest type and land use history. The earthworm effects also appear to be dynamic, as witnessed by a recent invasion of an Asian earthworm species in one of our forest stands.

  13. VISUALIZATION OF FREEZING PROGRESSION IN TURFGRASSES USING INFRARED VIDEO THERMOGRAPHY

    Science.gov (United States)

    Freezing injury can be a significant problem in turfgrasses. Understanding how freezing develops and ramifies throughout the plant could assist in the development of improved management or screening processes for cultivar improvemen. The development of freezing injury is not well understand due pa...

  14. Effects of the geophagous earthworm Metaphire guillelmi on sorption, mineralization, and bound-residue formation of 4-nonylphenol in an agricultural soil

    International Nuclear Information System (INIS)

    Effects of earthworms on fate of nonylphenol (NP) are obscure. Using 14C-4-NP111 as a representative, we studied the fate of 4-NP in an agricultural soil with or without the earthworm Metaphire guillelmi and in fresh cast of the earthworm. Sorption of 4-NP on the cast (Kd 1564) was significantly higher than on the parent soil (Kd 1474). Mineralization of 4-NP was significantly lower in the cast (13.2%) and the soil with earthworms (10.4%) than in the earthworm-free soil (16.0%). One nitro metabolite of 4-NP111 (2-nitro-4-NP111) was identified in the soil and cast, and the presence of the earthworm significantly decreased its amounts. The presence of earthworm also significantly decreased formation of bound residues of 4-NP in the soil. Our results demonstrate that earthworms could significantly change the fate of 4-NP, underlining that earthworm effects should be considered when evaluating behavior and risk of 4-NP in soil. - Highlights: The earthworm Metaphire guillelmi inhibited mineralization of 4-NP in the soil. A less-polar metabolite of 4-NP (2-nitro-4-NP111) was detected in the soil and cast. The presence of earthworm reduced the amount of 2-nitro-4-NP111 in the soil. M.guillelmi significantly reduced formation of bound residues of 4-NP in the soil. - Earthworms significantly changed the fate of 4-NP, highlighting that effects of earthworm should be considered when evaluating the behavior and risk of 4-NP in soil

  15. Effects of the endemic earthworm Allolobophora hrabei (?ernosvitov, 1935) on soil microbial communities of steppe grasslands.

    Czech Academy of Sciences Publication Activity Database

    Jirout, Ji?; Pil, Vclav

    2014-01-01

    Ro?. 76, September (2014), s. 249-256. ISSN 0038-0717 R&D Projects: GA ?R GAP504/12/0536 Institutional support: RVO:60077344 Keywords : bacteria * archaea * fungi * community composition * DGGE * earthworm Subject RIV: EH - Ecology, Behaviour Impact factor: 3.932, year: 2014

  16. APPLICATION OF PLANT AND EARTHWORM BIOASSAYS TO EVALUATE REMEDIATION OF A LEAD-CONTAMINATED SOIL

    Science.gov (United States)

    Earthworm acute toxicity, plant seed germination/root elongation (SG/RE) and plant genotoxicity bioassays were employed to evaluate the remediation of a lead-contaminated soil. The remediation involved removal of heavy metals by a soil washing/soil leaching treatment process. A p...

  17. Earthworms of the umava Biosphere Reserve and the effects of management practices on their communities.

    Czech Academy of Sciences Publication Activity Database

    Pil, Vclav

    Kostelec nad ?ernmi Lesy : ?esk zem?d?lsk univerzita v Praze, Lesnick fakulta, Katedra p?stovn les?, 2002. s. 9. [Monitoring, vzkum a management ekosystm? NP umava /3./. 28.11.2002-29.11.2002, Kostelec nad ?ernmi Lesy] Institutional research plan: CEZ:AV0Z6066911 Keywords : soil fauna * earthworms * umava Mts. Subject RIV: EH - Ecology, Behaviour

  18. A few new Western Australian earthworms (Oligochaeta: Megadrilacea: Megascolecidae sensu Blakemore, 2000

    Directory of Open Access Journals (Sweden)

    Robert J. Blakemore

    2014-11-01

    Full Text Available Earthworm samples, apparently collected in the 1980s from the northern Jarrah (Eucalyptus marginata forests of Western Australian and deposited in the London Natural History Museum, were studied. Due to limited time and budget only a few of the hundred samples were inspected. Description of just five new taxa are reported here.

  19. Responses of earthworms (Annelida: Lumbricidae) to disturbances in mountain alder swamp woods.

    Czech Academy of Sciences Publication Activity Database

    Pil, Vclav

    Brno : stav biologie obratlovc? AV?R, 2013. s. 175-176. ISBN 978-80-87189-14-6. [Zoologick dny Brno 2013. 07.02.2013-08.02.2013, Brno] Institutional support: RVO:60077344 Keywords : earthworms * disturbances * mountain alder swamp woods Subject RIV: EH - Ecology, Behaviour

  20. How do earthworms affect Collembola and the plant assemblages in primary succession?.

    Czech Academy of Sciences Publication Activity Database

    Mudrk, Ond?ej; Uteseny, Karoline; Frouz, Jan

    ?esk Bud?jovice : Institute of Soil Biology BC AS CR, 2009. s. 60. [Central European Workshop on Soil Zoology /10./. 21.04.2009-24.04.2009, ?esk Bud?jovice] Institutional research plan: CEZ:AV0Z60660521 Keywords : earthworms * Collembola * plant assemblages Subject RIV: EH - Ecology, Behaviour

  1. Interactions between earthworms and arsenic in the soil environment: a review

    Energy Technology Data Exchange (ETDEWEB)

    Langdon, Caroline J.; Piearce, Trevor G.; Meharg, Andrew A.; Semple, Kirk

    2003-08-01

    Relationships between earthworms and As-rich soils are discussed, examining mechanisms of tolerance, soil factors and possible trophic transfers. - Chemical pollution of the environment has become a major source of concern. In particular, many studies have investigated the impact of pollution on biota in the environment. Studies on metalliferous contaminated mine spoil wastes have shown that some soil organisms have the capability to become resistant to metal/metalloid toxicity. Earthworms are known to inhabit arsenic-rich metalliferous soils and, due to their intimate contact with the soil, in both the solid and aqueous phases, are likely to accumulate contaminants present in mine spoil. Earthworms that inhabit metalliferous contaminated soils must have developed mechanisms of resistance to the toxins found in these soils. The mechanisms of resistance are not fully understood; they may involve physiological adaptation (acclimation) or be genetic. This review discusses the relationships between earthworms and arsenic-rich mine spoil wastes, looking critically at resistance and possible mechanisms of resistance, in relation to soil edaphic factors and possible trophic transfer routes.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1988-06-01

    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 low level of organic matter. This difference disappeared when LC50 values were recalculated to concentrations in soil solution using adsorption data. Eisenia fetida andrei showed LC50 values lower than those of Lumbricus rubellus although bioaccumulation was generally higher in the latter species. Toxicity and bioaccumulation based on soil solution concentrations increased with increasing lipophilicity of the chlorophenols. The present results indicate that the toxicity and bioaccumulation and therefore the bioavailability of chlorophenols in soil to earthworms are dependent on the concentration in soil solution and can be predicted on the basis of adsorption data. Both the toxicity of and bioaccumulation data on chlorophenols in earthworms demonstrated surprisingly good agreement with those on chlorophenols in fish.

  3. Earthworms in floodplain ecosystems - do they contribute to the biodiversity of central European landscapes.

    Czech Academy of Sciences Publication Activity Database

    Pil, Vclav

    Grlitz : Staatliches Museum fr Naturkunde Grlitz, 2005. s. 20. [International Symposium Floodplains: Hydrology, Soils, Fauna and their Interactions. 11.09.2005-16.09.2005, St. Marientahl] Institutional research plan: CEZ:AV0Z60660521 Keywords : earthworms * floodplain ecosystems * central European landscapes Subject RIV: EH - Ecology, Behaviour

  4. Lethal concentrations of heavy metals in tissue of earthworms. Interim report No. 2

    Energy Technology Data Exchange (ETDEWEB)

    Bouche, M.B.; Brun, P.; Gal, J.Y.; Rida, A.

    1987-10-01

    This toxicological research report addresses lethal concentrations of heavy metals in tissue of earthworms. We have presented the work in progress in the first interim report to improve 1) ecotoxicological test, 2) field procedures, and 3) standardization of analysis. This second interim report deals mostly with toxicity tests because the point (3) is now in order and the field work was impossible during the last dry season. Nevertheless, analysis of soil samples are in progress and most data are on computer files. The authors here develop more in detail point (1) new results or state of the art in the improvement of toxicity tests. 1) They have repeated the toxicity tests trying to get the LC50 for the different metals: cadmium, copper, arsenic and mercury. 2) They worked out a method to analyze earthworms. In the first part, results of the toxicity test are presented with their interpretations and, in the second part, the analytical method is examined and results are given of the test earthworms analyzed, trying to establish a relation between earthworms and artisol from which they come.

  5. Polycyclic aromatic hydrocarbons and heavy metals in soil and earthworms of urban greens.

    Czech Academy of Sciences Publication Activity Database

    Pil, Vclav

    ?esk Bud?jovice : Institute of Soil Biology BC AS CR, 2009. s. 65. [Central European Workshop on Soil Zoology /10./. 21.04.2009-24.04.2009, ?esk Bud?jovice] R&D Projects: GA AV ?R IAA600660608 Institutional research plan: CEZ:AV0Z60660521 Keywords : polycyclic aromatic hydrocarbons * heavy metals * earthworms Subject RIV: EH - Ecology, Behaviour

  6. Ecotoxicological effects of earthworm following long-term Dechlorane Plus exposure.

    Science.gov (United States)

    Yang, Yang; Ji, Funian; Cui, Yibin; Li, Mei

    2016-02-01

    Dechlorane Plus (DP), similar to persistent organic pollutants, has been widely detected in environmental matrices, especially in sediment and soil. In this study, earthworms Eisenia fetida were exposed to 0.1, 0.5, 6.25 and 12.5mgkg(-1) DP for 28d. Lethality, oxidative stress, neurotoxicity and cellulase of E.fetida were assessed to investigate ecotoxicological effects of DP after long-term exposure. Results showed that the direct toxicity of DP was very low. However, death rate, as well as SOD activity, together with changes in activities of CAT, GSH-Px, and GSH levels, indicating that oxidative stress may play a significant role in DP exposure. In addition, DP also changes the AChE and cellulase activity of earthworms even under low DP concentration after long-term exposure. Moreover, comet assay results showed that DP exposure increased the levels of tDNA significantly (p<0.05) even in the lowest treatment (0.1mgkg(-1) DP). Combined with the results of enzyme activity, oxidative damage and comet assay, it can be suggested that earthworms experience more stress of DP during long-time exposure. This study provides insight into the toxicological effects of DP on earthworm model, and may be useful for risk assessment of DP on soil ecosystems. PMID:26619313

  7. The effects of production systems on earthworm assemblages in vineyards and apple orchards.

    Czech Academy of Sciences Publication Activity Database

    Pil, Vclav

    Washington : Society for Ecological Restoration, 2011. s. 162. [World Conference on Ecological Restoration /4./. 21.08.2011-25.08.2011, Mrida] Institutional research plan: CEZ:AV0Z60660521 Keywords : earthworm assemblages * vineyards * apple orchards Subject RIV: EH - Ecology, Behaviour

  8. The effects of production systems on earthworm assemblages in vineyards and apple orchards.

    Czech Academy of Sciences Publication Activity Database

    Pil, Vclav

    Brno : stav biologie obratlovc? AV ?R, 2011. s. 178-179. ISBN 978-80-87189-09-2. [Zoologick dny Brno 2011. 17.02.2011-18.02.2011, Brno] Institutional research plan: CEZ:AV0Z60660521 Keywords : earthworm assemblages * vineyards * apple orchards Subject RIV: EH - Ecology, Behaviour

  9. Earthworms and Humans in Vitro: Characterizing Evolutionarily Conserved Stress and Immune Responses to Silver Nanoparticles

    DEFF Research Database (Denmark)

    Hayashi, Yuya; Engelmann, Pter; Foldbjerg, Rasmus; Szab, Mariann; Somogyi, Ildik; Pollk, Edit; Molnr, Lszl; Autrup, Herman; Sutherland, Duncan S; Scott-Fordsmand, Janeck James; Heckmann, Lars-Henrik

    2012-01-01

    Little is known about the potential threats of silver nanoparticles (AgNPs) to ecosystem health, with no detailed report existing on the stress and immune responses of soil invertebrates. Here we use earthworm primary cells, cross-referencing to human cell cultures with a particular emphasis on t...

  10. Detrimental Influence of Invasive Earthworms on North American Cold-Temperate Forest Soils

    Science.gov (United States)

    Enerson, Isabel

    2012-01-01

    The topic of invasive earthworms is a timely concern that goes against many preconceived notions regarding the positive benefits of all worms. In the cold-temperate forests of North America invasive worms are threatening forest ecosystems, due to the changes they create in the soil, including decreases in C:N ratios and leaf litter, disruption of

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

    Science.gov (United States)

    Khalil, Abdelmonem M

    2015-12-01

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

  12. Bioremediation of polluted soil through the combined application of plants, earthworms and organic matter.

    Science.gov (United States)

    Macci, Cristina; Doni, Serena; Peruzzi, Eleonora; Ceccanti, Brunello; Masciandaro, Grazia

    2012-10-26

    Two plant species (Paulownia tomentosa and Cytisus scoparius), earthworms (Eisenia fetida), and organic matter (horse manure) were used as an ecological approach to bioremediate a soil historically contaminated by heavy metals and hydrocarbons. The experiment was carried out for six months at a mesoscale level using pots containing 90 kg of polluted soil. Three different treatments were performed for each plant: (i) untreated planted soil as a control (C); (ii) planted soil + horse manure (20:1 w/w) (M); (iii) planted soil + horse manure + 15 earthworms (ME). Both the plant species were able to grow in the polluted soil and to improve the soil's bio-chemical conditions, especially when organic matter and earthworms were applied. By comparing the two plant species, few significant differences were observed in the soil characteristics; Cytisus scoparius improved soil nutrient content more than Paulownia tomentosa, which instead stimulated more soil microbial metabolism. Regarding the pollutants, Paulownia tomentosa was more efficient in reducing the heavy metal (Pb, Cr, Cd, Zn, Cu, Ni) content, while earthworms were particularly able to stimulate the processes involved in the decontamination of organic pollutants (hydrocarbons). This ecological approach, validated at a mesoscale level, has recently been transferred to a real scale situation to carry out the bioremediation of polluted soil in San Giuliano Terme Municipality (Pisa, Italy). PMID:22911348

  13. Characterization of the organic fraction of earthworm humus and composts taken place starting from different substrates

    International Nuclear Information System (INIS)

    In order to evaluate the quality and the humification degree of different composted materials, the organic fraction of earthworm humus obtained from kitchen and farm residues, coffee pulp, biodegradable garbage and roses residues and of composts from roses and carnation residues were characterized chemically. Thus, determination and analysis of the C/N ratio, as well as the fractionation of the organic matter and the purification and characterization of the humic acids by C, H, N, 0 elemental analysis, UV-VIS spectroscopy were done and different humification parameters were found. The fractionation of the organic matter showed a low content of extracted carbon with respect to the normal content found in the soil humus. The elemental analysis data of the humic acids from the composts and the earthworm humus did not reveal important differences between these materials, while the E4/E6 ratio provided more evident changes. The results showed that the C/N ratio is not an absolute indicative of the Maturity State of the studied materials. The best parameters to estimate the maturity degree of the composts and the earthworm humus turned out to be the polymerization ratio, the humification index and the extracted carbon/non extracted carbon ratio. Among the evaluated materials, the earthworm of roses residues showed the best conditions with respect to content and quality of the organic matter to be added to a soil

  14. Earthworm species and burrows related to agricultural management of grass-clover in rotation

    DEFF Research Database (Denmark)

    Krogh, Paul Henning; Lamand, Mathieu

    2015-01-01

    Grass-clover is an important element in crop rotations due to its beneficial agronomic properties including nitrogen build-up, biodiversity stimulation and maintenance of soil macropores and it produces very high levels of earthworm biomass. We studied the relationship between crucial elements of grass-clover management in a crop rotation and earthworm diversity and macropore depth distribution. The dominance of anecics increased from an annual crop to the perennial grass-clover. Aporrectodea tuberculata decreased significantly from annuals to 3 year grass-clover. Cattle grazing favours the occurrence of coarse macropores (>5 mm ?) made by anecics, Aporrectodea longa and Lumbricus terrestris, while otherwise decreasing the number of fine-medium macropores (<5 mm ?) below the topsoil. Our study stresses the importance of considering subsoil macropores to complete the picture of earthworm influence on soil hydrology. The anecics are responsible for coarse macropores, while the smaller endogeic A. tuberculata isless important for coarse macropores and even negatively correlated with the abundant anecics and sensitive to the presence of grazing cattle compacting the topsoil. The detailed species-specific functional properties are crucial for successfully predicting the contribution to soil ecosystem services by earthworms.

  15. Toxicological effects of soil contaminated with spirotetramat to the earthworm Eisenia fetida.

    Science.gov (United States)

    Zhang, Qingming; Zhang, Guoli; Yin, Peijun; Lv, Yanzhen; Yuan, Shun; Chen, Jiqiang; Wei, Binbin; Wang, Caixia

    2015-11-01

    The aim of this study was to evaluate the potential toxicity of spirotetramat to the earthworm Eisenia fetida in a natural soil environment. Many biochemical markers, viz., superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), glutathione S-transferase (GST), cellulase, and malondialdehyde (MDA) contents were measured after exposure to 0.25, 1.25, and 2.5mgkg(-1) for 2, 7, 14, 21, and 28days. In addition, the comet assay was performed on earthworm coelomocytes to assess the level of genetic damage. The results demonstrate that the SOD activity and MDA content were significantly stimulated by the highest dose (2.5mgkg(-1)) of spirotetramat for the entire period of exposure. The activities of CAT and POD increased significantly by 2d and 21d, respectively, but the activities of both were significantly inhibited after prolonged exposure (28d). After an initial increase on the 2nd day, the cellulase activity in the high-dose treatment group was significantly inhibited for the entire remaining exposure period. The comet assay results demonstrate that spirotetramat (?2.5mgkg(-1)) can induce low and intermediate degrees of DNA damage in earthworm coelomocytes. The results indicate that spirotetramat may pose potential biochemical and genetic toxicity to earthworms (E. fetida), and this information is helpful for understanding the ecological toxicity of spirotetramat on soil invertebrate organisms. PMID:26081578

  16. Vermiremediation of dyeing sludge from textile mill with the help of exotic earthworm Eisenia fetida Savigny.

    Science.gov (United States)

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

    2013-09-01

    The aim of present study was for the vermiremediation of dyeing sludge from textile mill into nutrient-rich vermicompost using earthworm Eisenia fetida. The dyeing sludge was mixed with cattle dung in different ratios, i.e., 0:100 (D0), 25:75 (D25), 50:50 (D50), 75:25 (D75), and 100:0 (D100) with earthworms, and 0:100 (S0), 25:75 (S25), 50:50 (S50), 75:25 (S75), and 100:0 (S100) without earthworms. Minimum mortality and maximum population build-up were observed in a 25:75 mixture. Nitrogen, phosphorus, sodium, and pH increased from the initial to the final products with earthworms, while electrical conductivity, C/N ratio, organic carbon, and potassium declined in all the feed mixtures. Vermicomposting with E. fetida was better for composting to change this sludge into nutrient-rich manure. PMID:23508537

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

    Science.gov (United States)

    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...

  18. Anti-inflammatory, antipyretic and antioxidant activities of the earthworms extract

    Directory of Open Access Journals (Sweden)

    Hossam El-Din Mohamed Omar

    2012-01-01

    Full Text Available Introduction: Earthworms are the major biomass in soil. They have been widely used in traditional Chinese medicine for a long time. However, in the past few decades with the development of biochemical technologies the research on the pharmaceutical effects of earthworms has been commencement.Aims: Experiments were conducted to recognize the therapeutic properties such as anti-inflammatory, antipyretic and antioxidant activities of biologically active extract isolated from two species of earthworm (Pheretima hawayana Rosa and Allolobophora caliginosa Savigny.Materials and methods: inflammation in the hind paw of albino rat, Rattus rattus, was induced by histamine, pyrexia was induced by Escherichia coli in rats and liver damage was induced by injection of rats with CCl4. Anti-inflammatory drug - indomethacin, anti-pyretic drug - paracetamol and antioxidant drug - silymarin plus were used as standard drug for comparison.Results: Administration of Eearthworms extract (100 mg/kg and indomethacin (10 mg/kg, paracetamol (150 mg/kg, silymarin plus (150 mg/kg as standard drugs reduced and restored to normal the changes that induced by histamine, Escherichia coli and CCl4 in rats.Conclusions: The present study conclude that both extract of earthworms gave result as anti-inflammatory and anti-pyretic similar to the standard drugs. The extract of the two species showed various responds as antioxidants against CCl4 induced hepatotoxicity.

  19. The effects of earthworms Eisenia spp. on microbial community are habitat dependent.

    Czech Academy of Sciences Publication Activity Database

    Koubov, Anna; Chro?kov, Alica; Pil, Vclav; Snchez-Monedero, M.A.; Elhottov, Dana

    2015-01-01

    Ro?. 68, May-June (2015), s. 42-55. ISSN 1164-5563 R&D Projects: GA AV ?R IAA600200704; GA Mk LC06066 Institutional support: RVO:60077344 Keywords : earthworms * soil * compost * vermiculture * archaea * bacteria Impact factor: 1.719, year: 2014

  20. Earthworms and Plant Residues Modify Nematodes in Tropical Cropping Soils (Madagascar): A Mesocosm Experiment

    International Nuclear Information System (INIS)

    Free-living nematodes present several characteristics that have led to their use as bio indicators of soil quality. Analyzing the structure of nematofauna is a pertinent way to understand soil biological processes. Earthworms play an important role in soil biological functioning and organic matter dynamics. Their effects on soil nematofauna have seldom been studied. We studied the effect of the tropical endogeic earthworm, Pontoscolex corethrurus, on nematode community structure in a 5-month field mesocosm experiment conducted in Madagascar. Ten different treatments with or without earthworms and with or without organic residues (rice, soybean) were compared. Organic residues were applied on the soil surface or mixed with the soil. The abundance of nematodes (bacterial and fungal feeders) was higher in presence of P. corethrurus than in their absence. The type of plant residues as well as their localisation had significant effects on the abundance and composition of soil nematodes. The analysis of nematode community structure showed that earthworm activity led to an overall activation of the microbial compartment without specific stimulation of the bacterial or fungal compartment.

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

    Science.gov (United States)

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

    2008-12-01

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

  2. Alternatives to herbicides in an apple orchard, effects on yield, earthworms and plant diversity

    DEFF Research Database (Denmark)

    Andersen, L.; Kuehn, Birka Falk; Bertelsen, M.; Bruus, Marianne; Larsen, Sren Erik; Strandberg, Morten Tune

    2013-01-01

    tIn a newly established apple orchard eight alternative methods to weed control in the tree row werecompared to a herbicide treatment with respect to effects on tree growth, first-quality fruit yield, earth-worms and flora. All treatments were tested at two irrigation schedules, with similar amount...

  3. Effect on enzymes and histopathology in earthworm (Eisenia foetida) induced by triazole fungicides.

    Science.gov (United States)

    Gao, Minling; Song, Wenhua; Zhang, Jinyang; Guo, Jing

    2013-05-01

    Earthworms are an ideal biological model in toxicity assays and environment monitoring studies, especially for the toxicity of pesticides on soil ecosystem. However, There are very little data on the toxicity of triazoles on earthworms despite the fact that such data are critical in assessing their fate and potential toxic effects in soil organisms. To address this issue, earthworms were exposed to triazoles (triadimefon, triadimenol, difenoconazole and propiconazole) to study biochemical and histopathological examination. The results showed protein content significantly increased in treatment of difenoconazole compared to control. There were no significant differences between controls and triadimefon treated groups, while the glutathione peroxidase (GSH-Px) activity is significantly lower than control. Other triazoles also had an inhibitory effect on GSH-Px activity at higher concentration. The histopathological examination showed the epidermis and the epidermis cell of earthworm was ruined at lower triazoles concentration. The arrangement of smooth muscle layer disordered, and some cell disintegrated with concentration increasing of pesticides. Cell pyknosis, cytoplasm deep stained, nucleus concentrations were observed in the treated group with propiconazole. PMID:23474400

  4. Chlorpyrifos causes decreased organic matter decomposition by suppressing earthworm and termite communities in tropical soil

    International Nuclear Information System (INIS)

    Effects of pesticides on structural and functional properties of ecosystems are rarely studied under tropical conditions. In this study litterbag and earthworm field tests were performed simultaneously at the same tropical field site sprayed with chlorpyrifos (CPF). The recommended dose of CPF (0.6 kg a.i. ha-1) and two higher doses (4.4-8.8 kg a.i. ha-1) significantly decreased litter decomposition during the first 3 months after application, which could be explained from lower earthworm and termite abundances during this period. Species-specific effects of CPF on organism abundance and biomass were observed, with termites being mostly affected followed by the earthworm Perionyx excavatus; the earthworm Megascolex sp. was least affected. Recovery was completed within 6 months. Decomposition in the controls and lowest two treatments was completed within 4 months, which suggests the need for modification of standard test guidelines to comply with faster litter degradation under tropical conditions. - Effects of chlorpyrifos on functional and structural endpoints in soil.

  5. Nitric oxide production in celomocytes of the earthworm Eisenia hortensis following bacterial challenge

    Directory of Open Access Journals (Sweden)

    SR Cook

    2015-02-01

    Full Text Available In this in vitro investigation, nitric oxide (NO production was induced within celomocytes of the earthworm Eisenia hortensis following microbial challenge. Celomocytes were pre-loaded with the fluorescent indicator 4-amino-5-methylamino-2, 7-difluorofluorescein diacetate (DAF-FM DA in order to detect the presence of intracellular nitric oxide subsequent to a 16 h incubation with chemically-fixed soil bacteria including Bacillus megaterium, Arthrobacter globiformis, Pseudomonas stutzeri, and Azotobacter chroococcum at a range of multiplicities of infection (MOIs. Flow cytometric analysis measuring increases in relative fluorescence intensity (RFI, which is directly proportional to the amount of intracellular NO produced, permitted determination of statistical significance (p < 0.05 of exposed celomocytes compared to baseline controls. Significant increases in NO were detected reproducibly in celomocytes treated with all bacterial species used. The most prominent results were observed after exposure to Gram positive B. megaterium and A. globiformis where 100 % of earthworms tested exhibited statistically significant increases of RFI at MOIs of 100:1 and 500:1, respectively. Furthermore, significant decreases in NO production in bacteria-stimulated earthworm celomocytes incubated with the NOS inhibitor aminoguanidine hydrochloride were observed. These results demonstrate microbial induction of NO synthesis in earthworms and provide evidence of an antimicrobial role of NO in the innate immune system.

  6. Management of plant communities on set-aside land and its effects on earthworm communities.

    Czech Academy of Sciences Publication Activity Database

    Gormsen, D.; Hedlund, K.; Korthals, G. W.; Mortimer, S. R.; Pil, Vclav; milauerov, M.; Sugg, E.

    2004-01-01

    Ro?. 40, 3-4 (2004), s. 123-128. ISSN 1164-5563 Grant ostatn: Evropsk unie(XE) ENV4-CT95-0002 Keywords : earthworm community * plant community * land use Subject RIV: EH - Ecology, Behaviour Impact factor: 0.776, year: 2004

  7. Chlorpyrifos causes decreased organic matter decomposition by suppressing earthworm and termite communities in tropical soil

    Energy Technology Data Exchange (ETDEWEB)

    De Silva, P. Mangala C.S., E-mail: msilva@falw.vu.n [Department of Animal Ecology, VU University, De Boelelaan 1085, 1081 HV Amsterdam (Netherlands); Department of Zoology, Faculty of Science, University of Ruhuna, Matara (Sri Lanka); Pathiratne, Asoka [Department of Zoology, Faculty of Science, University of Kelaniya, Kelaniya (Sri Lanka); Straalen, Nico M. van; Gestel, Cornelis A.M. van [Department of Animal Ecology, VU University, De Boelelaan 1085, 1081 HV Amsterdam (Netherlands)

    2010-10-15

    Effects of pesticides on structural and functional properties of ecosystems are rarely studied under tropical conditions. In this study litterbag and earthworm field tests were performed simultaneously at the same tropical field site sprayed with chlorpyrifos (CPF). The recommended dose of CPF (0.6 kg a.i. ha{sup -1}) and two higher doses (4.4-8.8 kg a.i. ha{sup -1}) significantly decreased litter decomposition during the first 3 months after application, which could be explained from lower earthworm and termite abundances during this period. Species-specific effects of CPF on organism abundance and biomass were observed, with termites being mostly affected followed by the earthworm Perionyx excavatus; the earthworm Megascolex sp. was least affected. Recovery was completed within 6 months. Decomposition in the controls and lowest two treatments was completed within 4 months, which suggests the need for modification of standard test guidelines to comply with faster litter degradation under tropical conditions. - Effects of chlorpyrifos on functional and structural endpoints in soil.

  8. Influence of soil properties on the bioaccumulation and effects of arsenic in the earthworm Eisenia andrei.

    Science.gov (United States)

    Romero-Freire, A; Peinado, F J Martn; Ortiz, M Dez; van Gestel, C A M

    2015-10-01

    This study aimed at assessing the influence of soil properties on the uptake and toxicity effects of arsenic in the earthworm Eisenia andrei exposed for 4weeks to seven natural soils spiked with different arsenic concentrations. Water-soluble soil concentrations (AsW) and internal As concentrations in the earthworms (AsE) were greatly different between soils. These two variables were highly correlated and were key factors in earthworm toxicity response. AsW was explained by some soil properties, such as the pH, calcium carbonate content, ionic strength, texture or oxide forms. Toxicity showed a clear variation between soils, in some cases without achieving 50% adverse effect at the highest As concentration added (600mgkg(-1)). Nevertheless, soil properties did not show, in general, a high relation with studied toxicity endpoints, although the high correlation with AsW could greatly reduce indirectly As bioavailability and toxicity risk for earthworms. Obtained results suggest that soil properties should be part of the criteria to establishing thresholds for contaminated soils because they will be key in controlling As availability and thus result in different degrees of toxicity. PMID:26002360

  9. The effects of environmental parameters on the availability of cesium for earthworms

    International Nuclear Information System (INIS)

    The concentrations of potassium, stable cesium, calcium and ammonium in soil, and pH are known to affect the uptake of 134Cs from soil. Uncertain is whether this is a direct effect on the uptake (e.g. through competition for binding sites) or an indirect effect through a changing distribution of 134Cs between the solid and liquid phase of the soil. The uptake of 134Cs by earthworms from solution and soil has been studied to investigate these effects. The effects of potassium and stable cesium expressed per mmol added, were comparable: 134Cs accumulation decreases with potassium and stable cesium concentration in solution. No significant effects from varying pH or calcium and ammonium concentrations on 134Cs uptake from liquid medium were observed. 134Cs concentrations in the earthworms increased with temperature, which could mainly be explained by earthworm-related factors such as increased metabolism or feeding rate. Addition of calcium, potassium, ammonium and organic matter to soil increased the amount of 134Cs in soil solution significantly. However, the overall effects of additions of K+, Ca++, NH4+ and organic matter on the 134Cs concentrations in earthworms were non-significant. Based on the experiments in liquid medium increasing the concentration of potassium in soil solution showed to be most effective and most realistic in reducing 134Cs uptake. The results in soil indicate that the effect of potassium will depend on other soil characteristics as well

  10. Bioremediation of heavy metals and petroleum hydrocarbons in diesel contaminated soil with the earthworm: Eudrilus eugeniae.

    Science.gov (United States)

    Ekperusi, Ogheneruemu Abraham; Aigbodion, Iruobe Felix

    2015-01-01

    A laboratory study on the bioremediation of diesel contaminated soil with the earthworm Eudrilus eugeniae (Kingberg) was conducted. 5ml of diesel was contaminated into soils in replicates and inoculated with E. eugeniae for 90days. Physicochemical parameters, heavy metals and total petroleum hydrocarbons were analyzed using AAS. BTEX in contaminated soil and tissues of earthworms were determined with GC-FID. The activities of earthworms resulted in a decrease in pH (3.0%), electrical conductivity (60.66%), total nitrogen (47.37%), chloride (60.66%), total organic carbon (49.22%), sulphate (60.59%), nitrate (60.65%), phosphate (60.80%), sodium (60.65%), potassium (60.67%), calcium (60.67%), magnesium (60.68%), zinc (60.59%), manganese (60.72%), copper (60.68%), nickel (60.58%), cadmium (60.44%), vanadium (61.19%), chromium (53.60%), lead (60.38%), mercury (61.11%), arsenic (80.85%), TPH (84.99%). Among the BTEX constituents, only benzene (8.35%) was detected in soil at the end of the study. Earthworm tissue analysis showed varying levels of TPH (57.35%), benzene (38.91%), toluene (27.76%), ethylbenzene (42.16%) and xylene (09.62%) in E. eugeniae at the end of the study. The study has shown that E. eugeniae could be applied as a possible bioremediator in diesel polluted soil. PMID:26413446

  11. Viability of Bifidobacterium Pseudocatenulatum G4 after Spray-Drying and Freeze-Drying

    Directory of Open Access Journals (Sweden)

    Stephenie Wong

    2010-04-01

    Full Text Available Viability of Bifidobacterium pseudocatenulatum G4 following spray-drying and freeze-drying in skim milk was evaluated. After spray-drying, the strain experienced over 99% loss in viability regardless of the air outlet temperature (75 and 85 C and the heat-adaptation temperature (45 and 65 C, 30 min. The use of heat-adaptation treatment to improve the thermotolerance of this strain was ineffective. On the other hand, the strain showed a superior survival at 71.65%82.07% after freeze-drying. Viable populations of 9.3199.487 log10 cfu/g were obtained when different combinations of skim milk and sugar were used as cryoprotectant. However, the addition of sugars did not result in increased survival during the freeze-drying process. Hence, 10% (w/v skim milk alone is recommended as a suitable protectant and drying medium for this strain. The residual moisture content obtained was 4.41% 0.44%.

  12. Fundamental aspects of the freezing of cells, with emphasis on mammalian ova and embryos

    Energy Technology Data Exchange (ETDEWEB)

    Mazur, P.

    1980-01-01

    The problem in cryobiology is how to cool cells to -196/sup 0/C and return them to normal temperatures without killing them. One important factor is the presence of a protective additive like glycerol or dimethyl sulfoxide. Mammalian cells rarely survive freezing to below -40/sup 0/C in its absence. In the presence of an additive, survival is critically dependent on the cooling rate. Supraoptimal rates and suboptimal rates are both damaging. Death at supraoptimal rates is the result of the formation of intracellular ice and its recrystallization during warming. Death at suboptimal rates is a consequence of the major alterations in aqueous solutions produced by ice formation. The chief effects are a major reduction in the fraction of the solution remaining unfrozen at a given temperature and a major increase in the solute concentration of that fraction. The introduction of molar concentrations of additive greatly reduces both the fraction frozen and the concentration of electrolytes in the unfrozen channels and in the cell interior. Usually, freezing either kills cells outright or it results in survivors that retain full capacity to function. But there is the possibility that in some cases survivors may in fact be impaired genetically or physiologically. All evidence indicates that genetic damage does not occur. But there are clear examples in which freezing does induce nonlethal physiological damage. (ERB)

  13. USE AND EFFECT OF FREEZE BRANDING ON ROACH (RUTILUS RUTILUS L.

    Directory of Open Access Journals (Sweden)

    EVRARD G.

    2004-04-01

    Full Text Available We tested the effects of freeze branding on growth, survival and mark retention in roach Rutilus rutilus L. (82-268 mm in total length. Markings were applied at two positions on the skin: (1 the depressed area above the anal fin, (2 the muscles above the lateral line and between the caudal and dorsal fins. A control group received no mark. The experiment duration was 30 days, and 120 roach were selected and distributed into three lots. Retention rates were high and ranged between 94% for position 2 and 100% for position 1. Survival rate after 1 month was 87% for freeze branded roach at position 2, 90% for position 1 and 92% for unmarked fish. These differences were not statistically significant. A significant decrease of linear growth was observed for individuals marked at position 2 (3.2 mm.month-1, but the implication of the brand itself was unclear. We discuss the short- and long-term properties of freeze branding techniques on roach.

  14. Physiological differences beween fertilized and unfertilized mouse ova: glycerol permeability and freezing sensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Jackowski, S.C.

    1977-03-01

    The glycerol permeability and freezing sensitivity of mouse ova were studied for evidence of differences associated with fertilization. The times of ovulation, fertilization and first cleavage of ova were determined as a function of time after the administration of human chorionic gonadotropic, hormone, HCG, to female mice. Fertilization did not cause a large instantaneous change in glycerol permeability. Rather, the permeability coefficient for glycerol at approximately 3/sup 0/C gradually increased from 7.0 x 10/sup -7/ to 7.0 x 10/sup -6/ cm/min for fertilized ova isolated from about 1 hour to 16 hours after fertilization. The zonae pellucidae of fertilized and unfertilized ova did not act as detectable barriers to permeation by glycerol. No significant and immediate change was observed on the surface of the ovum as a result of fertilization. Survival after freezing was assayed by two techniques: measurement of the ability of the cells to fluoresce in the presence of fluorescein diacetate; successful development in culture. Survival of fertilized and unfertilized ova increased as a function of both the temperature and time of incubation in glycerol prior to freezing. It was concluded that permeation of a cell by glycerol enhances survival. The cooling rate that yielded optimal survival of zygotes in G/sub 2/ phase differed from that of unfertilized ova and zygotes in G/sub 1/ phase. The optimum rate for the latter cells was about 1/sup 0/C/min with survival being about 63 percent and 79 percent, respectively. The optimum rate for zygotes in G/sub 2/ ranged from 1/sup 0/C/min to 7/sup 0/C/min with survival being about 58 percent. The differences among the freezing sensitivities of unfertilized ova, zygotes in G/sub 1/ and zygotes in G/sub 2/ can be explained in terms of their differences in glycerol permeability and possibly in terms of the increased surface area associated with the number of microvilli on the G/sub 2/ zygotes.

  15. Role of Native and Exotic Earthworms in Plant Biopolymer Dynamics in Forest Soil

    Science.gov (United States)

    Filley, Timothy

    2010-05-01

    Many forests within northern North America are experiencing the introduction of earthworms for the first time, presumably since before the last major glaciation. Forest dynamics are undergoing substantial changes because of the activity of the mainly European lumbricid species. Documented losses in litter layers, expansion of A-horizons, loss of the organic horizon, changes in fine root density, and shifts in microbial populations have all been documented in invaded zones. Two free air CO2 enrichment (FACE) forest experiments (aspen FACE at Rhinelander, Wisconsin and sweet gum FACE at Oak Ridge National Lab, Tennessee) lie within the zones of invasion and exhibit differences in amounts of exotic and native species as well as endogeic (predominantly mineral soil dwelling) and epigeic (litter and organic matter horizon dwelling) types. Considerations of carbon accrual dynamics and relative input of above vs. below ground plant input in these young successional systems do not consider the potential impact of these ecosystem engineers. We investigated the impact of earthworm activity by tracking the relative abundance and stable carbon isotope compositions of lignin and substituted fatty acids extracted from isolated earthworms and their fecal pellets and from host soils. Indications of root vs leaf input to earthworm casts and fecal matter were derived from differences in the chemical composition of cutin, suberin, and lignin. The isotopically depleted CO2 used in FACE and the resulting isotopically depleted plant organic matter afford an excellent opportunity to assess biopolymer-specific turnover dynamics. We find that endogeic species are proportionately more responsible for fine root cycling while some epigeic species are responsible for microaggregation of foliar cutin. CSIA of fecal pellet lignin and SFA indicates how these biopolymer pools can be derived from variable sources, roots, background soil, foliar tissue within one earthworm. Additionally, CSIA indicates the distinct roles that different earthworm types have in "aging" surface soil biopolymer pools through encapsulation and upward transport of deeper soil carbon, and "freshening" deeper soil biopolymer pools through downward transport of surface carbon to deeper layers,. As earthworm species abundance and activity are not is steady state in many forests, the role of these important invertebrates should be more considered when assessing the changing soil state.

  16. The freezing and supercooling of garlic (Allium sativum L.)

    Energy Technology Data Exchange (ETDEWEB)

    James, Christian; Seignemartin, Violaine; James, Stephen J. [Food Refrigeration and Process Engineering Research Centre (FRPERC), University of Bristol, Churchill Building, Langford, Bristol BS40 5DU (United Kingdom)

    2009-03-15

    This work shows that peeled garlic cloves demonstrate significant supercooling during freezing under standard conditions and can be stored at temperatures well below their freezing point (-2.7 C) without freezing. The nucleation point or 'metastable limit temperature' (the point at which ice crystal nucleation is initiated) of peeled garlic cloves was found to be between -7.7 and -14.6 C. Peeled garlic cloves were stored under static air conditions at temperatures between -6 and -9 C for up to 69 h without freezing, and unpeeled whole garlic bulbs and cloves were stored for 1 week at -6 C without freezing. (author)

  17. Earthworms as bio-indicators of metal pollution in dump sites of Abeokuta City, Nigeria

    International Nuclear Information System (INIS)

    Metal concentrations (Zn, Pb, Mn, Cu, Cd and Cr) and contents were measured in earthworms (Libyodrilus violaceus) and soil samples from three non-contaminated sites and ten dump sites located in Abeokuta, Nigeria. Samples from control sites show (in general) levels of metals to be higher in earthworms than in soil samples, as shown by the mean concentrations, (earthworms-soil: - Zn:7.02, 6.74, Pb:5.04, 4.94, Mn 10.54, 10.41, Cu:1.03, 1.60., Cd: 0.80, 0.81 and Cr:0.55, 0.49 ?g/g) while for samples from dump sites, irrespective of the degree of pollution, the ratio of metal concentration in earthworms to soil samples were less than unity with the exception of Cd and Cr. The availability of metals in soils was also co-determined by the soil pH and soil organic matter which accounted for the trend of metal concentration at the various dump sites. For the control sites, the pH ranged from 5.40 - 6.74 and soil organic matter from 3.25% to 3.40%, while for the dump sites, values of 7.44-10.10 and 5.79% - 7.59% were obtained for soil pH and soil organic matter respectively. The metal ion concentration in both soil and earthworm samples followed the trend Pb > Zn > Mn > Cu > Cr > Cd. Dump sites with high levels of Pb were located by roadsides of busy highways. (Author) Mgtr.Julieta Soto Rojas Subdirectora Sistema de Bibliotecas, Documentacion e Informacion Universidad de Costa Rica jsotoatsibdi.ucr.ac.cr Tel. 207-4750, 207-4238, 207-4461, 207-5316 y 253-6152 Fax: 2342809

  18. Earthworms as bio-indicators of metal pollution in dump sites of Abeokuta City, Nigeria

    Directory of Open Access Journals (Sweden)

    O. Bamgbose

    2000-03-01

    Full Text Available Metal concentrations (Zn, Pb, Mn, Cu, Cd and Cr and contents were measured in earthworms (Libyodrilus violaceus and soil samples from three non-contaminated sites and ten dump sites located in Abeokuta, Nigeria. Samples from control sites show (in general levels of metals to be higher in earthworms than in soil samples, as shown by the mean concentrations, (earthworms-soil: - Zn:7.02, 6.74, Pb:5.04, 4.94, Mn 10.54, 10.41, Cu:1.03, 1.60., Cd: 0.80, 0.81 and Cr:0.55, 0.49 g/g while for samples from dump sites, irrespective of the degree of pollution, the ratio of metal concentration in earthworms to soil samples were less than unity with the exception of Cd and Cr. The availability of metals in soils was also co-determined by the soil pH and soil organic matter which accounted for the trend of metal concentration at the various dump sites. For the control sites, the pH ranged from 5.40 - 6.74 and soil organic matter from 3.25% to 3.40%, while for the dump sites, values of 7.44-10.10 and 5.79% - 7.59% were obtained for soil pH and soil organic matter respectively. The metal ion concentration in both soil and earthworm samples followed the trend Pb > Zn > Mn > Cu > Cr > Cd. Dump sites with high levels of Pb were located by roadsides of busy highways.

  19. Importncia ecolgica e ambiental das minhocas / Environmental and ecological importance of earthworms

    Scientific Electronic Library Online (English)

    Gerusa Pauli Kist, Steffen; Zaida Ins, Antoniolli; Ricardo Bemfica, Steffen; Rodrigo Josemar Seminoti, Jacques.

    2013-04-01

    Full Text Available As minhocas correspondem a um dos principais grupos de organismos edficos atuantes nos processos de movimentao de partculas e ciclagem de nutrientes. Este trabalho tem como objetivos discutir a importncia das minhocas para a melhoria e manuteno da sustentabilidade dos agroecossistemas, salie [...] ntando as formas de avaliao da comunidade de minhocas no solo e sua utilizao como ferramenta em avaliaes ambientais. Atravs da constante movimentao e atividade de ingesto de solo e resduos orgnicos, constroem galerias que contribuem com o aumento da aerao e da taxa de infiltrao de gua no solo. A liberao de excrementos na superfcie e no interior do solo modifica positivamente sua estrutura e fertilidade. A densidade e diversidade de minhocas em agroecossistemas pode ser determinada por diferentes mtodos de extrao. Algumas espcies de minhocas, por apresentarem sensibilidade a alteraes de uso e manejo do solo, so excelentes bioindicadoras ambientais, representando importante ferramenta para avaliao de impactos em ecossistemas. Abstract in english The earthworms represent a major group of soil organisms active in the process of moving particles and nutrient cycling. This paper aims to discuss the importance of earthworms to improve and maintain the sustainability of agroecosystems, emphasizing forms of community assessment of earthworms in th [...] e soil and its use as a tool in environmental assessments. Through constant movement and activity of soil ingestion and organic waste, they build galleries that contribute to increase the aeration and water infiltration in the soil. The release of faeces on the surface and within the soil positively modify its structure and fertility. The density and diversity of earthworms in agroecosystems can be determined by different extraction methods. Some species of earthworms, because they are excellen to changes in land use and management, are sensitive environmental bioindicators, representing an important tool to asses impacts on ecosystems.

  20. Anomalous freezing behavior of nanoscale liposomes

    DEFF Research Database (Denmark)

    Spangler, E. J.; Kumar, P. B. S.; Laradji, M.

    2012-01-01

    The effect of the finite size of one-component liposomes on their phase behavior is investigated via simulations of an implicit-solvent model of self-assembled lipid bilayers. We found that the high curvature of nanoscale liposomes has a significant effect on their freezing behavior. While the...... location of the freezing temperature of liposomes with diameters larger than 30 nm is the same as that of a planar membrane, the transition is broadened as the liposome diameters are decreased. For very small liposomes, with diameters smaller than 30 nm, the transitions of the two leaflets become...... chains in the two leaflets. At temperatures higher than T-g((u)), the liposomes are spherical and the lipids in both leaflets lack both positional and chain order. At temperatures between T-g((i)) and T-g((u)), the lipids in the outer leaflet exhibit chain order but lack positional order. In contrast the...