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1

Small Dendrobaena earthworms survive freezing better than large worms.  

Science.gov (United States)

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. PMID:17397817

Holmstrup, Martin; Overgaard, Johannes; Bayley, Mark

2007-06-01

2

Small Dendrobaena earthworms survive freezing better than large worms  

DEFF Research Database (Denmark)

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.

Holmstrup, Martin; Overgaard, Johannes

2007-01-01

3

Freeze tolerance in Aporrectodea caliginosa and other earthworms from Finland.  

Science.gov (United States)

Earthworms that live in subarctic and cold temperate areas must deal with frost even though winter temperatures in the soil are often more moderate than air temperatures. Most lumbricid earthworms can survive temperatures down to the melting point of their body fluids but only few species are freeze tolerant, i.e. tolerate internal ice formation. In the present study, earthworms from Finland were tested for freeze tolerance, and the glycogen reserves and glucose mobilization (as a cryoprotectant) was investigated. Freeze tolerance was observed in Aporrectodea caliginosa, Dendrobaena octaedra, and Dendrodrilus rubidus, but not in Lumbricus rubellus. A. caliginosa tolerated freezing at -5 degrees C with about 40% survival. Some individuals of D. octaedra tolerated freezing even at -20 degrees C. Glycogen storage was largest in D. octaedra where up to 13% of dry weight consisted of this carbohydrate, whereas the other species had only 3-4% glycogen of tissue dry weight. Also glucose accumulation was largest in D. octaedra which was the most freeze-tolerant species, but occurred in all four species upon freezing. It is discussed that freeze tolerance may be a more common phenomenon in earthworms than previously thought. PMID:17618617

Holmstrup, M; Overgaard, J

2007-08-01

4

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

Science.gov (United States)

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

Rasmussen, L M; Holmstrup, M

2002-12-01

5

No costs on freeze tolerance in genetically copper adapted earthworm populations (Dendrobaena octaedra).  

Science.gov (United States)

For nearly three centuries the area around Gusum, in south-east Sweden, has been highly polluted with copper. An earlier study in this area showed that populations of the freeze-tolerant earthworm Dendrobaena octaedra were genetically adapted to copper. Apparently, no life-history costs to reproduction or growth were imposed by this adaptation. In the present paper we therefore investigated how laboratory raised F1-generations of these populations coped when exposed to increased copper concentrations in the soil and to sub-zero temperatures. We found that D. octaedra from polluted sites accumulated the same amount of copper as reference worms. Furthermore, earthworms from polluted sites survived equally to reference worms when exposed to freezing temperatures (-8 or -12°C). However, when simultaneously exposed to the lowest temperature and copper, the worms from polluted sites survived significantly better than reference worms. The overall conclusion of this study is that worms from polluted sites seem to be better at handling copper and accrue no costs in terms of reduced cold tolerance in connection to genetic adaptation in these populations. PMID:21651991

Fisker, Karina Vincents; Sørensen, Jesper Givskov; Holmstrup, Martin

2011-09-01

6

Impacts of heavy metals, polyaromatic hydrocarbons, and pesticides on freeze tolerance of the earthworm Dendrobaena octaedra.  

Science.gov (United States)

Previous studies have shown that the interactions between chemicals and climatic stressors can lead to synergistically increased mortality. In the present study, we investigated the effect of seven common environmental contaminants on survival at -6 and 15°C as well as on reproduction at 15°C in the earthworm Dendrobaena octaedra. Three classes of chemicals were considered: Heavy metals (nickel, lead, and mercury), polycyclic aromatic hydrocarbons (pyrene and phenanthrene), and pesticides (abamectin and carbendazim). Phenanthrene interacted antagonistically with freezing temperatures, whereas no interaction was observed with any of the tested pesticides. Two of the three tested metals (nickel and mercury) reduced the freeze tolerance synergistically (mercury was especially potent). This suggests that traditional laboratory studies, in which organisms are exposed to increasing concentrations of a single compound under otherwise optimal conditions, may underestimate the toxicity of some metals to field populations living in cold areas. PMID:19499970

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

2009-11-01

7

Seasonal changes in lipid composition and glycogen storage associated with freeze-tolerance of the earthworm, Dendrobaena octaedra.  

Science.gov (United States)

The earthworm, Dendrobaena octaedra, is a common species in the uppermost soil and humus layers of coniferous forests and tundra in temperate and subarctic regions. The species is freeze-tolerant and may survive several months in a frozen state. Upon freezing, glycogen reserves are rapidly converted to glucose serving as a cryoprotectant and fuel for metabolism. In the present study we investigated the induction of freeze-tolerance under field conditions, and sought to find relationships between temperature, glycogen and fat reserves, membrane phospholipid composition and the degree of freeze-tolerance. Freeze-tolerance was induced when worms had experienced temperatures below 5 degrees C for 2 weeks or more. Freeze-tolerance was linked to the magnitude of glycogen reserves, which also fluctuated with field temperatures being highest in autumn and winter. On the other hand fat reserves seemed not to be linked with freeze-tolerance at all. However, high glycogen alone did not confer freeze-tolerance; alterations in the membrane phospholipid fatty acid composition (PLFA) were also necessary in order to secure freeze-tolerance. The changes in PLFA composition were generally similar to changes occurring in other ectothermic animals during winter acclimation with an increased degree of unsaturation of the PLFAs. PMID:19169691

Overgaard, Johannes; Tollarova, Michaela; Hedlund, Katarina; Petersen, Søren O; Holmstrup, Martin

2009-07-01

8

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

Science.gov (United States)

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 increased slightly whereas succinate levels remained constant. However, it is argued that other waste products (particularly propionate) could be the primary end product of a continued anaerobic metabolism. Calorimetric measures of the metabolic rate of frozen worms were in accord with values calculated from the reduction in glucose assuming that most ( approximately 90%) glucose was metabolised anaerobically. Both estimates of metabolic rate demonstrated a 10-fold metabolic depression associated with freezing. Thus, in addition to the suspected role of glucose as cryoprotectant, the present study demonstrates that glucose accumulation is vital to ensure substrate for long-term anaerobic metabolism in frozen worms. On the basis of the estimated metabolite levels, we calculate that the combined effect of metabolic depression and large glucose stores enables a projected 3 months survival of freezing at -2 degrees C of the ;average' D. octaedra. Such conditions are very likely to occur in the northern distribution ranges of this stress-tolerant earthworm. PMID:19252003

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

2009-03-01

9

Determining factors for cryoprotectant accumulation in the freeze-tolerant earthworm, Dendrobaena octaedra.  

Science.gov (United States)

The freeze-tolerant earthworm Dendrobaena octaedra is found in most of the European forest and tundra, Siberia, North America and Greenland where it over-winters in the top soil and encounters winter frost. In response to freezing this earthworm rapidly synthesises glucose which acts as a cryoprotectant. Frost tolerance varies extensively between geographical populations, and of the populations studied so far, the Finnish worms are most and the Danish worms least frost tolerant. Little is known about the determining factors for glucose synthesis and this study therefore investigated possible roles of acclimation and the cues for synthesis of glucose, in Finnish and Danish worms. The Finnish population had significantly larger glycogen reserves than the Danish during acclimation and in all worms, glucose synthesis was the result of an almost stoichemical reduction in glycogen stores. Maximum glucose levels were reached after the onset of freezing and were significantly higher in Finnish worms where the sugar accounted for as much as 5% of the fresh weight. On average, both the total glycogen phosphorylase activity and the active enzyme pool increased during acclimation in the Finnish but not the Danish populations. However, the increase in this enzyme was only significant during the freezing process. In this study, we show contrary to previous theory that glucose synthesis is initiated before the onset of freezing and that in this species, cryoprotectant synthesis is sensitive to very small temperature changes below 0 degrees C without the presence of ice. PMID:17694532

Overgaard, Johannes; Slotsbo, Stine; Holmstrup, Martin; Bayley, Mark

2007-10-01

10

Multivariate metabolic profiling using 1H nuclear magnetic resonance spectroscopy of freeze-tolerant and freeze-intolerant earthworms exposed to frost.  

Science.gov (United States)

Individuals of the freeze-tolerant earthworm, Dendrobaena octaedra, and four freeze-intolerant earthworm species (Dendrodrilus rubidus, Aporrectodea icterica, A. caliginosa, and A. longa) were frozen at -2 degree C. Control earthworms were exposed to +2 degree C. 1H nuclear magnetic resonance spectroscopy-based metabolic profiling in combination with multivariate pattern recognition methods (metabonomics) was used to produce a cross-species comparison. Several biochemical changes were detected as a result of freezing in all worm species, including an increase in relative free alanine concentrations, and an apparent conversion of adenosine to inosine. It was also possible to determine a number of biochemical changes that were unique to the freeze-tolerant species, D. octaedra. The most obvious difference was that, although all species showed an increase in glucose concentrations, the increase was largest in D. octaedra, and was coupled with a concomitant decrease in glycogen. This confirms that--like previously studied freeze-tolerant earthworm species--tolerance is effected by rapid glucose production from glycogen reserves. An additional difference noted was that succinate increased in all species on freezing, but the increase was least in D. octaedra. Furthermore there was no lactate accumulation in D. octaedra, whereas three of the other four species accumulated lactate. This indicates that anoxic metabolism was lowest in the freeze-tolerant species. PMID:14671686

Bundy, Jacob G; Ramløv, Hans; Holmstrup, Martin

2003-01-01

11

Hatchling turtles survive freezing during winter hibernation.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

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

1988-01-01

12

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

DEFF Research Database (Denmark)

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 increased slightly whereas succinate levels remained constant. However, it is argued that other waste products (particularly propionate) could be the primary end product of a continued anaerobic metabolism. Calorimetric measures of the metabolic rate of frozen worms were in accord with values calculated from the reduction in glucose assuming that most (similar to 90%) glucose was metabolised anaerobically. Both estimates of metabolic rate demonstrated a 10-fold metabolic depression associated with freezing. Thus, in addition to the suspected role of glucose as cryoprotectant, the present study demonstrates that glucose accumulation is vital to ensure substrate for long-term anaerobic metabolism in frozen worms. On the basis of the estimated metabolite levels, we calculate that the combined effect of metabolic depression and large glucose stores enables a projected 3 months survival of freezing at -2 degrees C of the 'average' D. octaedra. Such conditions are very likely to occur in the northern distribution ranges of this stress-tolerant earthworm.

Calderon, Sofia; Holmstrup, Martin

2009-01-01

13

Measuring freezing tolerance: survival and regrowth assays.  

Science.gov (United States)

Screening plants for freezing tolerance under tightly controlled conditions is an invaluable technique for studying freezing tolerance and selecting for improved winterhardiness. Artificial freezing tests of cereal plants historically have used isolated crown and stem tissue prepared by "removing all plant parts 3 cm above and 0.5 cm below the crown tissue" (Fowler et al., Crop Sci 21:896-901, 1981). Here, we describe a method of conducting freezing tolerance tests using intact plants grown in small horticultural containers, including suggested methods for collecting and analyzing the data. PMID:24852624

Skinner, Daniel Z; Garland-Campbell, Kimberly

2014-01-01

14

Changes in membrane phospholipids as a mechanistic explanation for decreased freeze tolerance in earthworms exposed to sublethal copper concentrations.  

Science.gov (United States)

At low temperature, cell membrane functionality depends on adjustments of membrane phospholipid fatty acid (PLFA) composition. We here test the hypothesis that previous exposure to copper (Cu) may deteriorate tolerance to freezing temperatures because of Cu-induced changes of PLFA composition of cell membranes in the freeze-tolerant earthworm Dendrobaena octaedra. Cu levels and freezing temperatures were varied in a full factorial design. We measured PLFA composition and lipid peroxidation. A highly significant interaction was observed between subzero temperatures and Cu concentrations above 120 mg/kg dry soil. Lipid peroxidation increased slightly in worms exposed to Cu. In particular, the analysis showed that Cu had a significant negative effect on the polyunsaturated PLFA, linoleic acid (18:2omega6,9), which has previously been reported to correlate positively (R2 = 0.92) with freeze tolerance in D. octaedra. This supports our hypothesis that reduced tolerance to freezing temperatures in Cu-exposed worms may be due to membrane damage. PMID:19708387

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

2009-07-15

15

Survival of freeze-dried Lactobacillus plantarum and Lactobacillus  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

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

2002-01-01

16

Method of freezing living cells and tissues with improved subsequent survival  

Energy Technology Data Exchange (ETDEWEB)

This invention relates to an improved method for freezing red blood cells, ther living cells, or tissues with improved subsequent survival, wherein constant-volume freezing is utilized that results in significantly improved survival compared with constant-pressure freezing; optimization is attainable through the use of different vessel geometries, cooling baths and warming baths, and sample concentrations.

Senkan, Selim M. (Oak Ridge, TN); Hirsch, Gerald P. (Oak Ridge, TN)

1980-01-01

17

Expression of freeze-responsive proteins, Fr10 and Li16, from freeze-tolerant frogs enhances freezing survival of BmN insect cells.  

Science.gov (United States)

To date, two novel freeze-responsive proteins, Fr10 and Li16, have been discovered in the wood frog, Rana sylvatica, and likely support freezing survival. Although previous studies have established tissue distribution of each protein, there have been no studies that explore their functional consequences in intolerant cells. To assess the ability of Fr10 and Li16 to confer freeze tolerance, we transfected each protein into a freeze-intolerant silkworm cell line (BmN). Selected controls were the transfection of an unrelated protein (CAT) and a no-transfection sample. Li16 and Fr10 showed 1.8 ± 0.1- and 1.7 ± 0.2-fold, respectively, greater survival after freezing at -6°C for 1 h than did transfection controls. To investigate how these novel proteins protect cells from freezing damage, protein structures were predicted from primary amino acid sequences. Analysis of the structures indicated that Fr10 is a secreted protein and may be a new type IV antifreeze protein, whereas Li16 may have intracellular membrane associated functions. This study shows that freezing protection can be provided to intolerant cells by the overexpression of transfected Li16 and Fr10 frog proteins. Results from this study will provide new insights into adapting intolerant cells for medical organ cryoprotection using a natural vertebrate model of tolerance. PMID:23657819

Biggar, Kyle K; Kotani, Eiji; Furusawa, Toshiharu; Storey, Kenneth B

2013-08-01

18

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

1993-01-01

19

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

1993-11-14

20

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

Science.gov (United States)

Enchytraeus albidus is a freeze-tolerant enchytraeid found in diverse habitats, ranging from supralittoral to terrestrial and spanning temperate to arctic regions. Its freeze tolerance is well known but the effect of salinity in this strategy is still poorly understood. We therefore studied the combined effect of salinity (0, 15, 35, 50‰ NaCl) and sub-zero temperatures (-5, -14, -20°C) on the freeze tolerance of E. albidus collected from two distinct geographical regions (Greenland and Germany). A full factorial design was used to study survival, and physiological and biochemical end points. The effect of salinity on the reproduction of German E. albidus was also assessed. Exposure for 48 h to saline soils prior to cold exposure triggered an increase in osmolality and decrease in water content. Worms exposed to saline soils had an improved survival of freezing compared to worms frozen in non-saline soils, particularly at -20°C (survival more than doubled). Differential scanning calorimetry measurements showed that the fraction of water frozen at -5 and -14°C was lower in worms exposed to 35‰ NaCl than in control worms. The lowering of ice content by exposure to saline soils was probably the main explanation for the better freeze survival in saline-exposed worms. Glucose increased with decreasing temperature, but was lower in saline than in non-saline soils. Thus, glucose accumulation patterns did not explain differences in freeze survival. Overall, the physiological responses to freezing of E. albidus from Greenland and Germany were similar after exposure to saline soils. Soil salinity up to 30‰ improved reproduction by a factor of ca. 10. PMID:23531829

Silva, A L Patrício; Holmstrup, M; Kostal, V; Amorim, M J B

2013-07-15

 
 
 
 
21

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

Science.gov (United States)

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.

Inada, Hidetoshi; Fujikawa, Seizo; Arakawa, Keita

22

Survival of freezing by hydrated tardigrades inhabiting terrestrial and freshwater habitats.  

Science.gov (United States)

The seasonality and unpredictability of environmental conditions at high altitudes and latitudes govern the life cycle patterns of organisms, giving rise to stresses that cause death or development of specific adaptations. Ice formation is a major variable affecting the survival of both freshwater fauna and fauna inhabiting lichens, mosses and leaf litter. Tardigrades occupy a wide range of niches in marine, freshwater and terrestrial environments. The highest number of species is found in terrestrial habitats thanks to their ability to enter anhydrobiosis and cryobiosis. The cryobiotic ability of tardigrade species from polar regions is well known. Consequently, we focused our research on the ability to survive freezing in the active hydrated state using seven tardigrade species differing in phylogenetic position and collected at various altitudes and from different habitats in a temperate area. Specimens were cooled at different cooling rates (from 0.31° C min(-1) to 3.26° C min(-1)). Even though the final survival and the time required by animals to recover to active life were both inversely related to the cooling rate, highly significant interspecific differences were found. Species survival ability ranged from excellent to none. Species living in xeric habitats withstood freezing better than those living in hygrophilous habitats, while true limnic species did not exhibit any cryobiotic ability. The ability to withstand freezing seems linked to the anhydrobiotic ability. The differences in cryptobiotic performance among tardigrade species seem more influenced by selective pressures linked to local adaptation to habitat characteristics than by phylogenetic relationships. PMID:21429723

Guidetti, Roberto; Altiero, Tiziana; Bertolani, Roberto; Grazioso, Pasqualina; Rebecchi, Lorena

2011-04-01

23

Vertebrate freezing survival: Regulation of the multicatalytic proteinase complex and controls on protein degradation.  

Science.gov (United States)

The wood frog, Rana sylvatica, survives weeks of whole body freezing during winter hibernation, expressing numerous metabolic adaptations that deal not only with freezing but with its consequences including organ ischemia and cellular dehydration. The present study analyzes the 20s multicatalytic proteinase (MCP) complex from skeletal muscle to determine how protein degradation is managed in the ischemic frozen state. MCP was partially purified and assayed fluorometrically using three AMC-labeled substrates to compare multiple states: control (5 degrees C acclimated), 24 h frozen at -2.5 degrees C, 4 or 8 h thawed at 5 degrees C, 8 h anoxia, and 40% dehydration. MCP from frozen frogs showed significantly different K(m) and V(max) values compared with controls; e.g., K(m) Z-LLE-AMC increased by 45% during freezing and 52% under anoxia whereas V(max) decreased by 40%. After thawing, K(m) was restored and V(max) rose by 2.2-fold. Incubations promoting protein kinase or phosphatase action on MCP showed that phosphatase treatment strongly increased V(max) implicating reversible phosphorylation in MCP regulation during freeze-thaw. Western blotting showed a 36% decrease in MCP protein in muscle from frozen frogs. The 20s MCP preferentially degrades oxidatively-damaged proteins and evidence of impaired function during freezing came from a 1.4-fold increase in protein carbonyl content in muscle and liver during freezing. Ubiquitin and ubiquitin conjugate levels were unchanged in muscle but changed markedly in liver during freeze-thaw. PMID:16448758

Woods, Ashley K; Storey, Kenneth B

2006-03-01

24

Survival of Ice Nucleation-Active and Genetically Engineered Non-Ice-Nucleating Pseudomonas syringae Strains after Freezing  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The survival after freezing of ice nucleation-active (INA) and genetically engineered non-INA strains of Pseudomonas syringae was compared. Each strain was applied to oat seedlings and allowed to colonize for 3 days, and the plants were subjected to various freezing temperatures. Plant leaves were harvested before and after freezing on two consecutive days, and bacterial populations were determined. Populations of the INA wild-type strain increased 15-fold in the 18 h after the oat plants inc...

1989-01-01

25

Urea loading enhances freezing survival and postfreeze recovery in a terrestrially hibernating frog.  

Science.gov (United States)

We tested the hypothesis that urea, an osmolyte accumulated early in hibernation, functions as a cryoprotectant in the freeze-tolerant wood frog, Rana sylvatica. Relative to saline-treated, normouremic (10 micromol ml(-1)) frogs, individuals rendered hyperuremic (70 micromol ml(-1)) by administration of an aqueous urea solution exhibited significantly higher survival (100% versus 64%) following freezing at -4 degrees C, a potentially lethal temperature. Hyperuremic frogs also had lower plasma levels of intracellular proteins (lactate dehydrogenase, creatine kinase, hemoglobin), which presumably escaped from damaged cells, and more quickly recovered neurobehavioral functions following thawing. Experimental freezing-thawing did not alter tissue urea concentrations, but did elevate glucose levels in the blood and organs of all frogs. When measured 24 h after thawing commenced, glucose concentrations were markedly higher in urea-loaded frogs as compared to saline-treated ones, possibly because elevated urea retarded glucose clearance. Like other low-molecular-mass cryoprotectants, urea colligatively reduces both the amount of ice forming within the body and the osmotic dehydration of cells. In addition, by virtue of certain non-colligative properties, it may bestow additional protection from freeze-thaw damage not afforded by glucose. PMID:18775934

Costanzo, Jon P; Lee, Richard E

2008-09-01

26

Bovine serum albumin: survival and osmolarity effect in bovine spermatozoa stored above freezing point.  

Science.gov (United States)

Liquid nitrogen preservation in remote farms is a limitation. The goal of this study was to determine optimum temperature above freezing point for bovine spermatozoa preservation using bovine serum albumin (BSA) as a supplementation. Pooled semen sample from three ejaculates was subjected to various BSA concentration (1, 4, 8 and 12 mg ml(-1)), before incubation in different above freezing point temperatures (4, 25 and 37 °C). Viability assessment was carried out against time from day 0 (fresh sample) until all spermatozoa become nonviable. Optimal condition for bovine spermatozoa storage was at 4 °C with 1 mg ml(-1) BSA for almost 7 days. BSA improved bovine spermatozoa viability declining rate to 44.28% at day 4 and 57.59% at day 7 compared to control, with 80.54% and 98.57% at day 4 and 7 respectively. Increase in BSA concentration did not improve sperm viability. Our results also confirmed that there was a strong negative correlation between media osmolarity and bovine spermatozoa survival rate with r = 0.885, P freezing point. PMID:21806660

Nang, C F; Osman, K; Budin, S B; Ismail, M I; Jaffar, F H F; Mohamad, S F S; Ibrahim, S F

2012-05-01

27

Water sorption properties, molecular mobility and probiotic survival in freeze dried protein-carbohydrate matrices.  

Science.gov (United States)

The moisture uptake and molecular mobility of freeze-dried powders containing whey protein isolate-carbohydrate matrices (1WPI:2maltodextrin; 1WPI:1maltodextrin:1d-glucose; and 1WPI:1maltodextrin:1l-glucose) and encapsulated Lactobacillus rhamnosus GG (LGG) in these matrices were investigated at 25 °C and 33% and 70% relative humidity (RH). The inactivation rate constant for probiotics in freeze-dried matrices were positively correlated (R(2) = 0.98) to moisture uptake and molecular mobility measured by NMR relaxometry. The stability of probiotics in glassy protein-carbohydrate matrices was dependent on the composition of the matrix. The partial substitution of maltodextrin with glucose (d- or l-) which improved microbial survival at 33% RH was related to the reduced molecular mobility and lower water uptake of the matrix. This study suggests that moisture uptake properties and molecular mobility of the matrix composition, as opposed to the relative humidity of the environment, are better determinants of probiotic viability during storage. Dynamic vapour sorption and NMR relaxometry are promising tools to assist in the selection of protein-carbohydrate matrices for enhancing probiotic viability during storage. PMID:23851914

Hoobin, Pamela; Burgar, Iko; Zhu, ShouChuang; Ying, DanYang; Sanguansri, Luz; Augustin, Mary Ann

2013-09-01

28

Repeated freeze–thaw cycles reduce the survival rate of osteocytes in bone-tendon constructs without affecting the mechanical properties of tendons  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Frozen bone-patellar tendon bone allografts are useful in anterior cruciate ligament reconstruction as the freezing procedure kills tissue cells, thereby reducing immunogenicity of the grafts. However, a small portion of cells in human femoral heads treated by standard bone-bank freezing procedures survive, thus limiting the effectiveness of allografts. Here, we characterized the survival rates and mechanisms of cells isolated from rat bones and tendons that were subjected to freeze–thaw tr...

2012-01-01

29

Influence of Serum and Glucose Additives on Survival of Actinobacillus pleuropneumoniae Aerosolized from the Freeze-Dried State  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Serum and/or glucose added to Actinobacillus pleuropneumoniae suspensions before freeze-drying significantly increased survival rates of bacteria in aerosols. Aerosols with predictable numbers of viable bacteria can be made as required in an aerosol infection model. Sucrose supplementation of impinger fluids increased recovery of viable A. pleuropneumoniae.

Hensel, Andreas

1994-01-01

30

Relationship between the cell surface hydrophobicity and survival of bacteria Zymomonas mobilis after exposures to ethanol, freezing or freeze-drying.  

Science.gov (United States)

An inverse linear relationship (P < 0.01) was detected between the cell surface hydrophobicity (CSH) and survival of ethanologenic bacteria Zymomonas mobilis 113S exposed to elevated (2.55 M) ethanol concentration. In the same way, viable cell counts of relatively hydrophobic Z. mobilis were less diminished by growing (0.85-3.40 M) ethanol concentrations as compared to more hydrophobic bacteria. Very similar inverse relationships (P < 0.01) were observed between the CSH of intact Z. mobilis and survival of cells subjected to subsequent freeze-drying or freezing/thawing cycles thereby affinity substantially lowered ability of hydrophobic bacteria to survive under adverse environments. Observed relationships were supported by significant correlations between independent analytical data of the carbohydrate content within fractions of lipopolysaccharide and surface proteins extracted from cells of varied hydrophobicity. The results suggest that the CSH could be of value to predict the ability of intact bacteria to endure stress conditions and should be monitored towards lower values during cultivation in order to reduce subsequent unwanted structural and physiological disturbances provoked by multiple stress factors. PMID:18690483

Shakirova, Laisana; Auzina, Lilija; Grube, Mara; Zikmanis, Peteris

2008-10-01

31

Repeated freeze-thaw cycles reduce the survival rate of osteocytes in bone-tendon constructs without affecting the mechanical properties of tendons.  

Science.gov (United States)

Frozen bone-patellar tendon bone allografts are useful in anterior cruciate ligament reconstruction as the freezing procedure kills tissue cells, thereby reducing immunogenicity of the grafts. However, a small portion of cells in human femoral heads treated by standard bone-bank freezing procedures survive, thus limiting the effectiveness of allografts. Here, we characterized the survival rates and mechanisms of cells isolated from rat bones and tendons that were subjected to freeze-thaw treatments, and evaluated the influence of these treatments on the mechanical properties of tendons. After a single freeze-thaw cycle, most cells isolated from frozen bone appeared morphologically as osteocytes and expressed both osteoblast- and osteocyte-related genes. Transmission electron microscopic observation of frozen cells using freeze-substitution revealed that a small number of osteocytes maintained large nuclei with intact double membranes, indicating that these osteocytes in bone matrix were resistant to ice crystal formation. We found that tendon cells were completely killed by a single freeze-thaw cycle, whereas bone cells exhibited a relatively high survival rate, although survival was significantly reduced after three freeze-thaw cycles. In patella tendons, the ultimate stress, Young's modulus, and strain at failure showed no significant differences between untreated tendons and those subjected to five freeze-thaw cycles. In conclusion, we identified that cells surviving after freeze-thaw treatment of rat bones were predominantly osteocytes. We propose that repeated freeze-thaw cycles could be applied for processing bone-tendon constructs prior to grafting as the treatment did not affect the mechanical property of tendons and drastically reduced surviving osteocytes, thereby potentially decreasing allograft immunogenecity. PMID:21116722

Suto, Kaori; Urabe, Ken; Naruse, Kouji; Uchida, Kentaro; Matsuura, Terumasa; Mikuni-Takagaki, Yuko; Suto, Mitsutoshi; Nemoto, Noriko; Kamiya, Kentaro; Itoman, Moritoshi

2012-03-01

32

Cold acclimation and lipid composition in the earthworm Dendrobaena octaedra.  

Science.gov (United States)

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

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

2007-08-01

33

Effects of slow freezing procedure on late blastocyst gene expression and survival rate in rabbit  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Studies of embryo cryopreservation efficiency have focused mainly on technical and embryo factors. To determine how a slow freezing process affects embryo and fetal development, we studied in vivo development ability after the freezing procedure by assessing blastocyst development at Day 6, implantation, and birth rates. A transcriptional microarray study was also performed to compare gene expression of 6-day-old rabbit embryos previously frozen and transferred into recipient rabbit fem...

Saenz Juano Ribes, Mari?a Los Desamparados; Marco Jime?nez, Francisco; Sa?nchez Pen?aranda, David; Joly, Thierry; Vicente Anto?n, Jose? Salvador

2012-01-01

34

Radioactive elements and earthworms in contaminated soils  

International Nuclear Information System (INIS)

Earthworms are one of the indispensable soil animals which treat soil with letting it through their gut and help increasing soil fertility. The effect of radioactive elements and comparative effect of heavy metals to the vital functions of earthworms were determined in laboratory conditions. Experiments were continued for a month, and first of all, each soil type, grey-brown soil from Ramana iodine plant territory of Baku city, brown soil from Aluminum plant territory of Ganja city, aborigine grey-brown soil of Absheron peninsula, treated with Ra and U salts as model variants and brown soil of Ganja city was analyzed by gamma-spectrometer for radionuclide determining at the beginning and at the end of the experiment. Earthworms (Nicodrilus Caliginosus Sav.trapezoides) aboriginal for Absheron peninsula and plant residues were added to the soil. At the end of the month the biomass, survival value, coprolite allocation value, food activity and catalase value in earthworms and in soil were determined. The gamma-spectrometric analysis results gave interesting values in coprolites, soils which had been treated through the earthworms' gut. In comparison with the initial variants in experimental results more percent of radioactivity was gathered in coprolites. By this way earthworms absorbed most of radioactive elements and allocated them as coprogenous substances on the upper layer of soil. During absorbing, some percents of radioactive elements were also gathered in gut cells of the earthworms. Thereby determination of some vital functions of earthworms was expedient. Thus, by the instrumentality of these experiments we can use earthworms for biodiagnosis and for bioremediation of contaminated soils with radionuclides and heavy metals.

2009-11-03

35

Earthworms and Soil Pollutants  

Directory of Open Access Journals (Sweden)

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.

Kazuyoshi Tamae

2011-11-01

36

Effects of earthworms density on growth, development and reproduction in Lumbricus rubellus (Hoffm.) and possible consequences for the intrinsic rate of population increase  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper, the influence of earthworm density is assessed on the life-history parameters: growth, development, reproduction, and survival of Lumbricus rubellus (Hoffm.). Density ranges from two to nine earthworms in 1-l containers, corresponding to field densities of 300–1350 earthworms m?2. Earthworms were kept under optimal laboratory conditions, with a surplus of food. The results show that at high earthworm density, individual growth is retarded, maturation delayed and cocoon prod...

Klok, C.

2007-01-01

37

Transport, motility, biofilm forming potential and survival of Bacillus subtilis exposed to cold temperature and freeze-thaw.  

Science.gov (United States)

In cold climate regions, microorganisms in upper layers of soil are subject to low temperatures and repeated freeze-thaw (FT) conditions during the winter. We studied the effects of cold temperature and FT cycles on the viability and survival strategies (namely motility and biofilm formation) of the common soil bacterium and model pathogen Bacillus subtilis. We also examined the effect of FT on the transport behavior of B. subtilis at two solution ionic strengths (IS: 10 and 100 mM) in quartz sand packed columns. Finally, to study the mechanical properties of the bacteria-surface bond, a quartz crystal microbalance with dissipation monitoring (QCM-D) was used to monitor changes in bond stiffness when B. subtilis attached to a quartz substrate (model sand surface) under different environmental conditions. We observed that increasing the number of FT cycles decreased bacterial viability and that B. subtilis survived for longer time periods in higher IS solution. FT treatment decreased bacterial swimming motility and the transcription of flagellin encoding genes. Although FT exposure had no significant effect on the bacterial growth rate, it substantially decreased B. subtilis biofilm formation and correspondingly decreased the transcription of matrix production genes in higher IS solution. As demonstrated with QCM-D, the bond stiffness between B. subtilis and the quartz surface decreased after FT. Moreover, column transport studies showed higher bacterial retention onto sand grains after exposure to FT. This investigation demonstrates how temperature variations around the freezing point in upper layers of soil can influence key bacterial properties and behavior, including survival and subsequent transport. PMID:24768703

Asadishad, Bahareh; Olsson, Adam L J; Dusane, Devendra H; Ghoshal, Subhasis; Tufenkji, Nathalie

2014-07-01

38

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.

2005-11-01

39

Anatomical regulation of ice nucleation and cavitation helps trees to survive freezing and drought stress  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Water in the xylem, the water transport system of plants, is vulnerable to freezing and cavitation, i.e. to phase change from liquid to ice or gaseous phase. The former is a threat in cold and the latter in dry environmental conditions. Here we show that a small xylem conduit diameter, which has previously been shown to be associated with lower cavitation pressure thus making a plant more drought resistant, is also associated with a decrease in the temperature required for ice nucleation in t...

Lintunen, A.; Ho?ltta?, T.; Kulmala, M.

2013-01-01

40

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

Science.gov (United States)

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

Asadishad, Bahareh; Ghoshal, Subhasis; Tufenkji, Nathalie

2013-12-17

 
 
 
 
41

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, earthworms were first processed into a powder by freeze drying. Then, samples were measured by utilizing 10 s exposure to 30 W microwave power. This method showed the potential to quantitatively measure MWNTs in earthworms at low concentrations (~0.1 ?g in 20 mg of earthworm). Also, a simple MWNT bioaccumulation study in earthworms indicated a low bioaccumulation factor of 0.015±0.004. With an appropriate sample processing method and instrumental parameters (power and exposure time), this technique has the potential to quantify MWNTs in a variety of sample types (plants, earthworms, human blood, etc.). PMID:23298789

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

2013-02-15

42

Effect of NaHCO3, MgSO4, Sodium Ascorbate, Sodium Glutamate, Phosphate Buffer on Survival of Lactobacillus bulgaricus During Freeze-drying  

Directory of Open Access Journals (Sweden)

Full Text Available In the present study, the experiments were investigated the effects of different concentrations of cryoprotective agents, such as NaHCO3, MgSO4, sodium ascorbate, sodium glutamate, phosphate buffer, respectively, which used on survival of Lactobacillus bulgaricus during freeze drying. The number of viable cells and survival ratio were measured by the plate count method. The results were as follows: cryoprotective agents played important roles in survival of Lactobacillus bulgaricus during freeze drying. When the relative volume of phosphate buffer was 1.5 (v/v, the number of viable cells was highest, while the survival ratio reached highest, the concentration of sodium ascorbate was 4.5%.

He Chen

2013-06-01

43

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: English Abstract in english 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.

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

2001-12-15

44

Rapid warming increases survival of slow-frozen sibling oocytes: a step towards a single warming procedure irrespective of the freezing protocol?  

Science.gov (United States)

Nowadays, human oocytes/embryos are cryopreserved via slow freezing or vitrification. The aim of this study was to evaluate a rapid warming protocol for slow-frozen human oocytes based on the standard warming procedure for vitrification. This was a prospective study on 216 sibling oocytes randomized for either conventional rapid thawing or rapid warming with vitrification warming solution. The primary endpoint was morphological assessment of survival at 2h. Surviving oocytes were divided into two subgroups: (i) parthenogenetically activated; and (ii) fixed and observed for spindle/chromosome configuration. Secondary endpoints were parthenogenetic development and spindle/metaphase configuration. Survival rate with rapid warming was higher (92/102, 90.2%) than with rapid thawing (85/114, 74.6%; P=0.005), and after 3d of culture the rapidly warmed parthenotes had more blastomeres compared with those rapidly thawed (P=0.042). Meiotic spindle and chromosomal configuration were not significantly influenced by rapid warming or rapid thawing. The finding of this study allows IVF centres to increase the efficiency of oocyte slow freezing, enabling survival rates comparable to vitrification protocols, and potentially to optimize costs by using the same warming protocol for both slow-frozen and vitrified reproductive cells. PMID:24657075

Parmegiani, Lodovico; Tatone, Carla; Cognigni, Graciela Estela; Bernardi, Silvia; Troilo, Enzo; Arnone, Alessandra; Maccarini, Antonio Manuel; Di Emidio, Giovanna; Vitti, Maurizio; Filicori, Marco

2014-05-01

45

Removal of mercury from soil with earthworms  

Energy Technology Data Exchange (ETDEWEB)

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.

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

1994-12-31

46

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

Science.gov (United States)

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

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

2005-06-01

47

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)

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.

Banova?ki Zorana

2013-01-01

48

Potential negative effects of earthworm prey on damage to turfgrass by omnivorous mole crickets (Orthoptera: Gryllotalpidae).  

Science.gov (United States)

The severity of damage to host plants by omnivorous pests can vary according to the availability of plant and animal prey. Two omnivorous mole crickets, Scapteriscus vicinus Scudder and S. borellii Giglio-Tos, were used to determine if the availability of prey influences damage to hybrid bermudagrass by adult mole crickets. Experiments were conducted in arenas with either grass alone (control), grass plus one mole cricket, grass plus earthworms (Eisenia fetida Savigny), or grass with earthworms and a mole cricket. Root growth variables (e.g., volume, dry weight) after 4 wk and weekly measurements of top growth were compared among the treatments. Surprisingly, bermudagrass infested with either mole cricket species caused no significant reduction in root growth and a minimal reduction on top growth with S. vicinus compared with controls. Survival of earthworms with S. borellii was significantly lower than survival in the earthworm-only treatment suggesting predation. Survival of earthworms with S. vicinus, however, was not different from the earthworm-only treatment. The addition of earthworm prey with mole crickets did not significantly impact bermudagrass root or shoot growth relative to grass with only mole crickets. Despite no negative impacts from earthworms or mole crickets separately, earthworms plus mole crickets negatively impact several root parameters (e.g., length) suggesting an interaction between these two soil-dwelling invertebrates. Increased use of more target-selective insecticides in turfgrass may increase available prey. This work suggests that alternative prey, when present, may result in a negative impact on turfgrass roots from foraging omnivorous mole crickets. PMID:23068170

Xu, Yao; Held, David W; Hu, Xing Ping

2012-10-01

49

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

DEFF Research Database (Denmark)

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 2 °C for 47 days. 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 â??averageâ? worms would be able to survive for a total of 83 days 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.

C. Jørgensen, Sofia; Overgaard, Johannes

2008-01-01

50

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

Directory of Open Access Journals (Sweden)

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.

Barcelo P., M.

1988-01-01

51

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

Energy Technology Data Exchange (ETDEWEB)

The study design incorporates the exposure of two generations of earthworms, Eisenia foetida, and includes the sensitive developmental stage following emergence from the cocoon. Adult earthworms (F{sub 0} generation) were exposed to nominal concentrations of 16, 31, 63, 125 and 250 mg A.I. copper sulfate/kg in composted cattle manure for 14 days. Cocoons were collected six times throughout the F{sub 0} generation exposure. Upon collection, individual cocoons were weighed and transferred to separate aliquots of treated and untreated exposure manure and were allowed to hatch. Hatched F{sub 1} earthworms were allowed to mature for 21 days before being counted and individually weighed. Parameters monitored and statistically analyzed were: F{sub 0} burrowing time at initiation, F{sub 0} survival following 7 and 14 days of exposure, cocoon production, cocoon weight, cocoon viability, number and weight of F{sub 1} earthworms at 21 days post-hatch. The following endpoints clearly demonstrated chronic effects in at least the highest exposure concentration: cocoon production, mean cocoon weight, sum of cocoon weights, cocoon viability, number and weight of surviving earthworms (F{sub 1}) at 21 days post-hatch, mean and total earthworm (F{sub 1}) biomass at 21 days post-hatch. Although the acute LC50 of copper sulfate to Eisenia foetida was previously determined to be 1,100 {+-} 380 mg copper sulfate/kg, this methodology indicates that chronic toxicity effects can be observed at substantially lower concentrations.

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

1994-12-31

52

Freezing induces a loss of freeze tolerance in an overwintering insect.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Cold-hardy insects overwinter by one of two main strategies: freeze tolerance and freeze avoidance by supercooling. As a general model, many freeze-tolerant species overwinter in extreme climates, freeze above -10 degrees C via induction by ice-nucleating agents, and once frozen, can survive at temperatures of up to 40 degrees C or more below the initial freezing temperature or supercooling point (SCP). It has been assumed that the SCP of freeze-tolerant insects is unaffected by the freezing ...

2004-01-01

53

Earthworm contamination by PCBs and heavy metals  

Energy Technology Data Exchange (ETDEWEB)

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

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

1985-01-01

54

New records of earthworms (Oligochaeta from Madagascar  

Directory of Open Access Journals (Sweden)

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.

Razafindrakoto, M.

2010-10-01

55

New earthworm records from Bulgaria (Oligochaeta, Lumbricidae  

Directory of Open Access Journals (Sweden)

Full Text Available 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.

Szederjesi, T.

2013-06-01

56

Metal accumulation in earthworms inhabiting floodplain soils  

Energy Technology Data Exchange (ETDEWEB)

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.

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

57

Vulnerable Earthworm Species Identified from Nilgiri Biosphere Reserve  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 s...

Mahesh Mohan; Shylesh Chandran, M. S.; Ramasamy, E. V.

2011-01-01

58

Effect of C60 fullerenes on the accumulation of weathered p,p'-DDE by plant and earthworm species under single and multispecies conditions.  

Science.gov (United States)

The use of engineered nanomaterials has increased dramatically in recent years, but an understanding of nanomaterial fate and effects in the environment is lacking. In particular, the interaction of nanomaterials with coexisting organic contaminants and the subsequent implications for sensitive biota is almost completely unknown. Here, the effect of C60 fullerenes on the accumulation of weathered dichlorodiphenyldichloroethylene (p,p'-DDE; DDT metabolite) by Cucurbita pepo (pumpkin) and Eisenia fetida (earthworm) was determined under single and multispecies conditions. The plants, in the presence or absence of earthworms, were grown in soil containing weathered DDE (200 ng/g) and 0 or 1,670 mg/kg?C60 fullerenes. Plants and earthworms were added either simultaneously or sequentially (earthworms after plants). Neither DDE nor C60 had an impact on survival or biomass of plants and earthworms, although fullerenes significantly decreased (29.6-39.0%) the relative root mass. Under single or multispecies conditions, C60 had little impact on DDE bioaccumulation by either species. The DDE concentrations in non-fullerene-exposed shoots, roots, and earthworms were 181, 7,400, and 8,230 ng/g, respectively. On fullerene exposure, the DDE content was nonsignificantly lower at 163, 7280, and 7540 ng/g, respectively. In the presence of the earthworms, C60 significantly decreased the shoot DDE content (28.6%), but no impact on root concentrations was observed. Root DDE content was unaffected by the presence of fullerenes and decreased by 21.6 to 37.5% during coexposure with earthworms. Earthworm DDE content was decreased by plant presence. Earthworms added to soils after plant harvest accumulated more DDE but were unaffected by the C60 exposure. Additional work is necessary, but these findings suggest that fullerenes may have minimal impact on the bioaccumulation of weathered cocontaminants in soil. PMID:23401244

Kelsey, Jason W; White, Jason C

2013-04-01

59

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 on frozen ready-to-eat (RTE) shrimp as the pathogen could grow following thawing. In this study, antimicrobial-coating treatments alone, or in combination with cryogenic freezing, were evaluated for their ability to inhibit the growth of Listeria innocua, a surrogate for L. monocytogenes, on RTE shrimp. Cooked RTE shrimp were inoculated with L. innocua at 3 population levels and treated with coating solutions consisting of chitosan, allyl isothiocyanate (AIT), or lauric arginate ester (LAE). The treated shrimp were then stored at -18 °C for 6 d before being thawed at 4, 10, or 22 °C for either 24 or 48 h. Results revealed that antimicrobial coatings achieved approximately 5.5 to 1 log CFU/g reduction of L. innocua on RTE shrimp after the treatments, depending on the inoculated population levels. The coating-treated shrimp samples had significantly (P < 0.05) less L. innocua than controls at each thawing temperature and time. Cryogenic freezing in combination with coating treatments did not achieve synergistic effects against L. innocua. Antimicrobial coatings can help to improve product safety by reducing Listeria on RTE shrimp. PMID:23957407

Guo, Mingming; Jin, Tony Z; Scullen, O Joseph; Sommers, Christopher H

2013-08-01

60

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

Science.gov (United States)

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

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

2012-01-01

 
 
 
 
61

Biochemical diversity of betaines in earthworms  

Energy Technology Data Exchange (ETDEWEB)

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.

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

62

Measuring freezing tolerance: electrolyte leakage and chlorophyll fluorescence assays.  

Science.gov (United States)

Quantitative assessment of freezing tolerance is essential to unravel plant adaptations to cold temperatures. Not only the survival of whole plants but also impairment of detached leaves after a freeze-thaw cycle can be used to accurately quantify plant freezing tolerance in terms of LT50 values. Here we describe two methods to determine the freezing tolerance of detached leaves using different physiological parameters. Firstly, we illustrate how to assess the integrity of (predominantly) the plasma membrane during freezing using an electrolyte leakage assay. Secondly, we provide a chlorophyll fluorescence imaging protocol to determine the freezing tolerance of the photosynthetic apparatus. PMID:24852625

Thalhammer, Anja; Hincha, Dirk K; Zuther, Ellen

2014-01-01

63

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

Science.gov (United States)

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

McLaughlin, Molly

1994-01-01

64

Biological assessment of contaminated land using earthworm biomarkers in support of chemical analysis  

International Nuclear Information System (INIS)

Biological indicators can be used to assess polluted sites but their success depends on the availability of suitable assays. The aim of this study was to investigate the performance of two earthworm biomarkers, lysosomal membrane stability measured using the neutral red retention assay (NRR-T) and the total immune activity (TIA) assay, that have previously been established as responsive to chemical exposure. Responses of the two assays were measured following in situ exposure to complexly contaminated field soils at three industrial sites as well as urban and rural controls. The industrial sites were contaminated with a range of metal (cadmium, copper, lead, zinc, nickel and cobalt) and organic (including polycyclic aromatic hydrocarbons) contaminants, but at concentrations below the 'New Dutch List' Intervention concentrations. Exposed earthworms accumulated both metals and organic compounds at the contaminated sites, indicating that there was significant exposure. No effect on earthworm survival was found at any of the sites. Biomarker measurements, however, indicated significant effects, with lower NRR-T and TIA found in the contaminated soils when compared to the two controls. The results demonstrate that a comparison of soil pollutant concentrations with guideline values would not have unequivocally identified chemical exposure and toxic effect for soil organisms living in these soils. However, the earthworm biomarkers successfully identified significant exposure and biological effects caused by the mixture of chemicals present

2004-09-01

65

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

Energy Technology Data Exchange (ETDEWEB)

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

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

1998-01-01

66

Impact of Thermal History on Tolerance of Meloidogyne hapla Second-stage Juveniles to External Freezing  

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Low temperature induced physiological changes that increased the ability of second-stage juveniles of Meloidogyne hapla to survive external freezing. Second-stage juveniles in polyethylene glycol solution were exposed to -4 , 0, 4, or 24 C, and then their survival was determined after ice-induced freezing of the suspensions at - 4 C for 24 hours. Survival was greatest for juveniles exposed to 4 C before freezing. Some juveniles were killed by exposure to - 4 C before freezing of the suspensio...

1992-01-01

67

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

Science.gov (United States)

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

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

2013-02-01

68

Contact freezing: a review  

Directory of Open Access Journals (Sweden)

Full Text Available This manuscript compiles both theoretical and experimental information on contact freezing with the aim to better understand this potentially important but still not well quantified heterogeneous freezing mode. There is no complete theory that describes contact freezing and how the energy barrier has to be overcome to nucleate an ice crystal by contact freezing. Experiments on contact freezing indicate that it can initiate ice formation at the highest temperatures. A difference in the freezing temperatures between contact and immersion freezing has been found using different instrumentation and different ice nuclei. There is a lack of data on collision rates in most of the reported data, which inhibits a quantitative calculation of the freezing efficiencies. Thus, new or modified instrumentation to study this heterogeneous freezing mode in the laboratory and in the field are needed. Important questions concerning contact freezing and its potential role for ice cloud formation and climate are also summarized.

L. A. Ladino

2013-03-01

69

Productivity Potentials and Nutritional Values of Semi-arid Zone Earthworm (Hyperiodrilus euryaulos; Clausen, 1967 Cultured in Organic Wastes as Fish Meal Supplement  

Directory of Open Access Journals (Sweden)

Full Text Available In the present study 60 Adult Earthworms (H. euryaulos of weight and length range 1.7-3.0 g (mean-2.34±0.91 g and 13.0-28.0 cm (mean-21.5±5.8 cm, respectively were cultured for 12 weeks. The productivity potential and nutrient composition of earthworm (H. euryaulos cultured in two rearing substrata (Cellulose Substrate (Control - Coded Hs1 and Dry Neem and leaves and soil Substrate - Coded Hs2 were assessed using six wooden boxes stocked in triplicates at the rate of 92.7 g earthworms per box. The higher total final weight, weekly weight gain, relative growth rate, specific growth rate and survival of 400.6 g kg-1 of substrate, 25.7 g/week/substrate, 332.5, 0.76/day and 99.0% while the lower of 367.5 g kg-1 of substrate, 22.9 g/week, 296.4, 0.71/day and 98.0% were recorded in earthworm cultured in cellulose substrate and the soil substrate respectively. The proximate analyses, mineral compositions and amino acids indices were comparable to those of conventional fish meal. Based on the results of this study, the utilization of cellulose substrate is recommended for the culture of earthworm and the inclusion of the earthworm meal is guarantee as a reliable and nutritional dependable fish meal supplement.

A.O. Sogbesan

2007-01-01

70

Antioxidant responses of the earthworm Lampito mauritii exposed to Pb and Zn contaminated soil  

Energy Technology Data Exchange (ETDEWEB)

The aim of this study was to provide fundamental data on the biochemical analysis of antioxidant defences in the earthworm exposed to low levels (75, 150, 300 mg kg{sup -1} soil) of Pb and Zn. In order to attain this objective, adult Lampito mauritii were exposed to different doses of Pb and Zn separately for 28 days and the concentrations of oxidized and reduced glutathione, activities of glutathione-S-transferase, glutathione peroxidase and glutathione reductase were assessed. Dose-dependent perturbations were observed in the glutathione-glutathione-S-transferase system and other antioxidant enzymes during the early phase of the exposure to Pb. In the Zn exposed earthworm, the glutathione-glutathione-S-transferase system remained stable and the stimulation of glutathione peroxidase and glutathione reductase activities occurred significantly only on day 14 at 300 mg Zn kg{sup -1}. It is concluded that the antioxidants are directly involved in the adaptive response of Lampito mauritii for survival in metal contaminated soil. - Survival of Pb and Zn exposed earthworm Lampito mauritii depends on antioxidative system.

Maity, Sulata [Centre for Environmental Studies, Siksha-Bhavana, Visva-Bharati, Santiniketan 731 235 (India)], E-mail: maitysulata@yahoo.co.in; Roy, Sonali [Department of Zoology, Siksha-Bhavana, Visva-Bharati, Santiniketan 731 235 (India)], E-mail: roysonali2005@rediffmail.com; Chaudhury, Shibani [Centre for Environmental Studies, Siksha-Bhavana, Visva-Bharati, Santiniketan 731 235 (India)], E-mail: shibanic@sancharnet.in; Bhattacharya, Shelley [Department of Zoology, Siksha-Bhavana, Visva-Bharati, Santiniketan 731 235 (India)], E-mail: bhattacharyashelley@rediffmail.com

2008-01-15

71

Antioxidant responses of the earthworm Lampito mauritii exposed to Pb and Zn contaminated soil  

International Nuclear Information System (INIS)

The aim of this study was to provide fundamental data on the biochemical analysis of antioxidant defences in the earthworm exposed to low levels (75, 150, 300 mg kg-1 soil) of Pb and Zn. In order to attain this objective, adult Lampito mauritii were exposed to different doses of Pb and Zn separately for 28 days and the concentrations of oxidized and reduced glutathione, activities of glutathione-S-transferase, glutathione peroxidase and glutathione reductase were assessed. Dose-dependent perturbations were observed in the glutathione-glutathione-S-transferase system and other antioxidant enzymes during the early phase of the exposure to Pb. In the Zn exposed earthworm, the glutathione-glutathione-S-transferase system remained stable and the stimulation of glutathione peroxidase and glutathione reductase activities occurred significantly only on day 14 at 300 mg Zn kg-1. It is concluded that the antioxidants are directly involved in the adaptive response of Lampito mauritii for survival in metal contaminated soil. - Survival of Pb and Zn exposed earthworm Lampito mauritii depends on antioxidative system

2008-01-01

72

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

1988-08-01

73

Variation in seedling freezing response is associated with climate in Larrea  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Variation in freezing severity is hypothesized to have influenced the distribution and evolution of the warm desert evergreen genus Larrea. If this hypothesis is correct, performance and survival of species and populations should vary predictably along gradients of freezing severity. If freezing environment changes in the future, the ability of Larrea to adapt will depend on the structure of variation for freezing resistance within populations. To test whether freezing responses vary among an...

Medeiros, Juliana S.; Marshall, Diane L.; Maherali, Hafiz; Pockman, William T.

2012-01-01

74

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.

2010-01-01

75

Correlations between Lumbricus terrestris survival and gut microbiota  

Directory of Open Access Journals (Sweden)

Full Text Available 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 weeks. Results : We found a tendency that the crystalline cellulose fed earthworms survived better than the high energy fed earthworms (p=0.08. Independent of feeding we found that the bacterial group related to Ferrimonadaceae was correlated to an increased lifespan (p=0.01. We also found a positive correlation between Ruminococcaceae related bacteria and cellulase activity in the earthworm gut (p=0.05. Surprisingly, however, the cellulase activity was not correlated to the feeding regime. Conclusion : Taken together, the interactions between diet, gut microbiota and lifespan seem complex.

Knut Rudi

2012-04-01

76

Bacterial Diversity in the Digestive Tract of Earthworms (Oligochaeta  

Directory of Open Access Journals (Sweden)

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.

Hortensia Brito-Vega

2009-01-01

77

Clay dispersability in moist earthworm casts of different soils.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Earthworms were fed soil from two polders, differing in soil age and land use (grass and arable). Sterilised and non-sterilised moist earthworm casts were, directly or after ageing (for 2, 4, 8 and 20 weeks), analysed for clay dispersability and polysaccharide content, either as such, or after treatment with water or K-periodate/K-borate. Results for casts were compared with those for field aggregates of comparable size that were treated similarly.Fresh earthworm casts were very unstable. Soi...

Marinissen, J. C. Y.; Nijhuis, E.; Breemen, N.

1996-01-01

78

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

2000-06-01

79

Microbial Environment Affects Innate Immunity in Two Closely Related Earthworm Species Eisenia andrei and Eisenia fetida  

Science.gov (United States)

Survival of earthworms in the environment depends on their ability to recognize and eliminate potential pathogens. This work is aimed to compare the innate defense mechanisms of two closely related earthworm species, Eisenia andrei and Eisenia fetida, that inhabit substantially different ecological niches. While E. andrei lives in a compost and manure, E. fetida can be found in the litter layer in forests. Therefore, the influence of environment-specific microbiota on the immune response of both species was followed. Firstly, a reliable method to discern between E. andrei and E. fetida based on species-specific primers for cytochrome c oxidase I (COI) and stringent PCR conditions was developed. Secondly, to analyze the immunological profile in both earthworm species, the activity and expression of lysozyme, pattern recognition protein CCF, and antimicrobial proteins with hemolytic function, fetidin and lysenins, have been assessed. Whereas, CCF and lysozyme showed only slight differences in the expression and activity, fetidin/lysenins expression as well as the hemolytic activity was considerably higher in E. andrei as compared to E. fetida. The expression of fetidin/lysenins in E. fetida was not affected upon the challenge with compost microbiota, suggesting more substantial changes in the regulation of the gene expression. Genomic DNA analyses revealed significantly higher level of fetidin/lysenins (determined using universal primer pairs) in E. andrei compared to E. fetida. It can be hypothesized that E. andrei colonizing compost as a new habitat acquired an evolutionary selection advantage resulting in a higher expression of antimicrobial proteins.

Dvorak, Jiri; Mancikova, Veronika; Pizl, Vaclav; Elhottova, Dana; Silerova, Marcela; Roubalova, Radka; Skanta, Frantisek; Prochazkova, Petra; Bilej, Martin

2013-01-01

80

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

Directory of Open Access Journals (Sweden)

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 147.24±27.16 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.

Abdelmonem Mohamed Khalil

2013-01-01

 
 
 
 
81

Contact tests for pentachlorophenol toxicity to earthworms  

Energy Technology Data Exchange (ETDEWEB)

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

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

1994-12-31

82

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

Energy Technology Data Exchange (ETDEWEB)

Transfer of radionuclides ({sup 232}Th and {sup 238}U) and associated metals (As, Cd, Pb and Cr) from soil to free-living earthworm species was investigated in a thorium ({sup 232}Th) 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 {sup 232}Th 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 ({sup 238}U) 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 0.03-0.08 and 0.09-0.25, for {sup 232}Th and {sup 238}U, 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 {mu}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 {sup 232}Th and {sup 238}U, 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: Black-Right-Pointing-Pointer Transfer of radionuclides ({sup 232}Th, {sup 238}U) and metals (As, Cr, Cd and Pb) from soil to earthworms was investigated. Black-Right-Pointing-Pointer Individual organisms' variability and species specific accumulation were demonstrated. Black-Right-Pointing-Pointer Results suggested that earthworms could survive in habitats with multiple contaminants. Black-Right-Pointing-Pointer Estimated radiological risk was not significant despite high soil concentrations of radionuclides.

Mrdakovic Popic, Jelena, E-mail: jelena.mrdakovic.popic@umb.no; Salbu, Brit; Skipperud, Lindis

2012-01-01

83

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 0.03–0.08 and 0.09–0.25, 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.

2012-01-01

84

Effects of cadmium and lead on the life-cycle parameters of juvenile earthworm Eisenia fetida.  

Science.gov (United States)

Juveniles Eisenia fetida were exposed to cadmium (1-500µgCdg(-1)) and lead (20-2500µgPbg(-1)) for fourteen weeks in order to evaluate the impact on life-cycle parameters (survival, growth, sexual maturation, and cocoon production) and lipid peroxidation (expressed as concentration of malondialdehyde (MDA)). Both metals were found to significantly affect survival of the juveniles (fourteen-week LC50 296±125µgCdg(-1) and 911±164µgPbg(-1)) and alter their development. Cd and Pb severely affected the weight of the juveniles, prolonged the time to sexual maturation (at the highest concentrations, earthworms did not reach sexual maturity at all), and reduced cocoon production. LC50 significantly decreased with the time of earthworm exposure, indicating that chronic exposure to the same levels of contaminants in the soil may have more detrimental consequences than short-term exposure. A survival model showed that the survival probability for the juveniles decreased significantly with time and the concentration of metals in the soil. The metals induced a significant increase in MDA concentration (2.98-fold and 1.54-fold at 250µgCdg(-1) and 2500µgPbg(-1), respectively), and the content of MDA was negatively related to the weight of the juveniles and the percentage of mature individuals (p<0.05). PMID:24561241

Žaltauskait?, J?rat?; Sodien?, Inga

2014-05-01

85

Earthworm communities in grasslands and horticultural soils  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In a survey of 42 farm sites, comprising grassland and two types of horticultural farms (growing vegetables or flower bulbs), earthworm communities were sampled by hand-sorting and a number of soil physico-chemical characteristics recorded. For heavy metals the availability in the soil solution was estimated based on the measured absolute content. Abundance, biomass and species richness were significantly higher in grassland soils than in horticultural soils, and within the horticultural farm...

Didden, W. A. M.

2001-01-01

86

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

2012-01-01

87

Vulnerable Earthworm Species Identified from Nilgiri Biosphere Reserve  

Directory of Open Access Journals (Sweden)

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.

E.V. Ramasamy

2011-01-01

88

Effect of Soil Physical State on the Earthworms in Hungary  

International Nuclear Information System (INIS)

Hungarian authors have long been discussing the role of earthworms in improving soil productivity. Earthworm counts in our higher quality soils are similar to those found in soils where more attention is paid to earthworm activity. Negative impacts that are independent of farming such as sustained dry spells in the summer also affect earthworm counts. Negative impacts that definitely depend on farming include land use causing soil moisture loss, deep stubble treatment leaving the soil without cover, and ploughing in the summer without subsequent pressing. The climate change is having both positive and negative impacts. Weather patterns are causing losses but adopting climate mitigating tillage are generating benefits. In the trials results so far show that tillage focusing on preserving soil moisture, structure, and organic materials, covering the surface in the critical months as well as adequate soil loosening are fundamental pre-requisites for making the soil a favourable habitat for earthworms.

2010-01-01

89

Microscale interactions between earthworms and microorganisms: a review  

Directory of Open Access Journals (Sweden)

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.

Zirbes, L.

2012-01-01

90

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

Science.gov (United States)

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

Sheppard, S C; Stephenson, G L

2012-01-01

91

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

Science.gov (United States)

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

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

2012-01-01

92

Kinetic freeze out  

CERN Multimedia

Freeze out of particles across a space-time hypersurface is discussed in kinetic models. The calculation of final momentum distribution of emitted particles is described for freeze out surfaces, with spacelike normals. The resulting non-equilibrium distribution does not resemble, the previously proposed, cut Juttner distribution, and shows non-exponential p_t-spectra similar to the ones observed in experiments.

Magas, V K; Csernai, László P; Grassi, Frédérique; Greiner, W; Hama, Y; Kodama, T; Lázár, Z I; Stöcker, H; Lázár, Zs.I.

1999-01-01

93

Intensifying rock freezing  

Energy Technology Data Exchange (ETDEWEB)

The paper evaluates problems associated with shaft excavation in rock strata with intensive water influx. A mine shaft 605 m deep is sunk by means of rock freezing in two stages: from 0 to 390 m in the first stage and from 390 to 605 m in the second. Rock types and rock stratification are given in two tables. The AO-1200P and the DAON35OP compressors with brine temperature to minus 35/sup 0/C are used. Time effects on rock temperature and methods for temperature control are evaluated. Rock freezing efficiency is assessed by a double measuring method: using thermocouples in freezing pipes and using test boreholes drilled in frozen rocks and an ultrasonic measuring system. More than one test borehole should be used due to freezing borehole deviations. A method used in the Mosbass coal mines is also critically evaluated. It consists in simultaneous use of rock freezing and mine draining. Mine draining intensifies water filtration which reduces rock freezing efficiency. Therefore the method may be used when rock freezing temperature is increased from minus 20/sup 0/C to minus 35/sup 0/C. The system has been successfully tested in the Berezovsk coal mine in which an inclined mine shaft was sunk by rock freezing combined with draining.

Shparber, P.A.

1983-05-01

94

Freezing and Food Safety  

Science.gov (United States)

... usually the result of excessive drying due to improper packaging or over-lengthy storage. [ Top of Page ] Freeze Rapidly Freeze food as ... very well with the egg white or other ingredients. [ Top of Page ] Freezer Storage Chart (0 °F) Note: Freezer storage is for ...

95

The Freezing Bomb  

Science.gov (United States)

The extreme pressures that are generated when water freezes were traditionally demonstrated by sealing a small volume in a massive cast iron "bomb" and then surrounding it with a freezing mixture of ice and salt. This vessel would dramatically fail by brittle fracture, but no quantitative measurement of bursting pressure was available. Calculation…

Mills, Allan

2010-01-01

96

Extracellular freezing-induced mechanical stress and surface area regulation on the plasma membrane in cold-acclimated plant cells  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Freezing tolerance is an important feature for plant survival during winter. In plants, extracellular freezing occurs at subzero temperatures, resulting in dehydration and mechanical stresses upon the plasma membrane. However, many plants can acquire enhanced freezing tolerance by exposure to non-freezing temperatures, which is referred to as cold acclimation. The plasma membrane is the primary site of freezing injury. During cold acclimation, the lipid composition in the plasma membrane chan...

2009-01-01

97

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

DEFF Research Database (Denmark)

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 (β-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 β 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 earthwormâ??s 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 Ã?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.

Lund, Marie Braad; Holmstrup, Martin

98

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

Science.gov (United States)

An experiment was conducted during 1998-1999, in a deciduous forest located in the semi-arid tropics of central India, to evaluate the suitability of different forest litters as food material for the tropical epigeic earthworms i.e. Eisenia fetida (Savigny), Perionyx excavatus (Perrier) and Dicogaster bolaui (michaelsen). The aim was to examine the influence of these earthworms on the decomposition processes of three types of forest litters i.e. Tectona grandis (teak), Madhuca indica (mahua) and Butea monosperma (palas), on the maintenance of quality in a vermicomposting system, and to assess the effect of applications of in situ prepared vermicomposts on the growth of forest trees. The results indicated that T. grandis litter was the most suitable food material for the earthworms possibly because it contained high reserves of mineral nutrients. Comparisons of the survival and reproduction rates of the three epigeic earthworm species indicated that a higher reproduction rate was maintained for E. fetida compared to P. excavatus and D. bolaui in the decomposition of these forest litters. The rates of growth and population increases of E. fetida approximately doubled after 12 weeks of litter decomposition. The litter decomposition process was associated strongly with the quality of the materials and their chemical composition. Irrespective of earthworm inoculations, the levels of available nutrient such as NH(4)-N, NO(3)-N, available P and K increased significantly (pgrandis litter compost>M. indica litter compost>B. monosperma litter compost. The mature decomposed litter had lower C/N ratios (11.3-24.8:1), water-soluble carbon (0.30-0.58%), water-soluble carbohydrates (0.35-0.71%) and larger cation exchange capacity/total organic carbon ratios than the values in the parent forest litter. The lignin content increased with maturation with a concomitant decrease in cellulose resulting in higher lignin/cellulose ratios. Application of all three vermicomposts to forest trees significantly improved their heights and diameters over those of control trees, although the increases were lower than those resulting from the chemical fertilizer applications. However, soil biological activities i.e. soil respiration, soil microbial biomass carbon and dehydrogenase activity were greater by application of vermicomposts over that after application of inorganic fertilizer in a new plantation of T. grandis. PMID:12618041

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

2003-07-01

99

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)

2004-09-06

100

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

 
 
 
 
101

Multi-element analyses of earthworms for radioecology and ecotoxicology  

Energy Technology Data Exchange (ETDEWEB)

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)

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

102

Metabolic changes during estivation in the common earthworm Aporrectodea caliginosa  

DEFF Research Database (Denmark)

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 water content. Gas exchange was depressed by 50% after worms entered estivation and by 80% after a further 30 d of dehydration. Urea concentrations increased from 0.3 to 1 micromol g(-1) dry mass during this time. Although (1)H-NMR did not provide the identity of the osmolytes responsible for the initial increase in osmolality after estivation, it showed that alanine increased to more than 80 mmol L(-1) in the long-term-estivation group. We propose that alanine functions as a nitrogen depot during dehydration and is not an anaerobe product in this case.

Bayley, Mark; Overgaard, Johannes

2011-01-01

103

Earthworms produce phytochelatins in response to arsenic.  

Science.gov (United States)

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

Liebeke, Manuel; Garcia-Perez, Isabel; Anderson, Craig J; Lawlor, Alan J; Bennett, Mark H; Morris, Ceri A; Kille, Peter; Svendsen, Claus; Spurgeon, David J; Bundy, Jacob G

2013-01-01

104

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

Science.gov (United States)

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

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

2008-06-01

105

Comparative toxicity of ten organic chemicals to four earthworm species  

Energy Technology Data Exchange (ETDEWEB)

Ten organic chemicals were tested for toxicity to four earthworm species: Allolobophora tuberculata, Eisenia fetida, Eudrilus eugeniae and Perionyx excavatus, using the European Economic Community's (EEC) earthworm artificial soil and contact testing procedure. The phenols were the most toxic chemicals tested, followed by the amine, substituted benzenes, halogenated aliphatic hydrocarbon, polycyclic aromatic hydrocarbon and phthalate as the least toxic chemical tested. Correlations among species within each type of test for a given chemical were extremely high, suggesting that the selection of earthworm test species does not markedly affect the assessment of a chemical's toxicity. The correlation between the two tests was low for all test species. The contact test LC50 for a given chemical cannot be directly correlated to an artificial soil test LC50 for the same earthworm species.

Neuhauser, E.F.; Durkin, P.R.; Malecki, M.R.; Anatra, M.

1986-01-01

106

Further contribution to knowledge of the earthworms of Šumadija, Serbia  

Directory of Open Access Journals (Sweden)

Full Text Available The authors present the results of recent investigations of earthworms from Šumadija. Research was carried out during 1996-2003 and included natural and cultivated biotopes from various parts of Šumadija. We found 27 taxa including six species new for the earthworm fauna of Šumadija: Dendrobaena alpina, Helodrilus cernosvitovianus, Octolasion cyaneum, Octodrilus complanatus, Serbiona serbica, and Serbiona paratuleskovi. Up to 1995, the total number of earthworm taxa in Šumadija was 37. After our present study this number has risen to 43 taxa. As for the zoogeographical position of the earthworms of Šumadija, 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.

Stojanovi? Mirjana M.

2005-01-01

107

Identification and Classification of Earthworm Species in Guyana  

Directory of Open Access Journals (Sweden)

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.

Preeta Saywack

2011-01-01

108

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

2003-10-08

109

Identification of bacteria community associated with earthworm gut  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The role of earthworms in soil fertility and transformation of organic waste was regulary cited to be of first importance. Associated to these macro-invertebrates, a large diversity of micro-orgnisms are found indirectly in their closed environment or directly in their gut. Functional aspects of these interactions and symbiosis in relation with soil characteristics and fertility rates are poorly developed. Here, the micro-organisms diversity and potential related functions of earthworm gut we...

Lemtiri, Aboulkacem; Alabi, Taofic; Bodson, Bernard; Brostaux, Yves; Destain, Marie-france; Aubinet, Marc; Colinet, Gilles; Vandenbol, Micheline; Portetelle, Daniel; Haubruge, Eric; Francis, Fre?de?ric

2012-01-01

110

Earthworm (Eisenia andrei Avoidance of Soils Treated with Cypermethrin  

Directory of Open Access Journals (Sweden)

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 Fisher’s exact test (p ? 1.000 for each soil and treatment, demonstrating that the different soil characteristics, the cypermethrin concentrations and formulation, as well as the smaller amounts of soil and earthworms did not influence the avoidance behavior of the earthworms to cypermethrin. The number and range of treatments used in this study do not allow a detailed recommendation of the conditions applied here, but to the best of our knowledge, this is the first reported attempt to identify the avoidance of pesticide treated tropical soils by earthworms.

Mara M. de Andréa

2011-11-01

111

Earthworm (Eisenia andrei) Avoidance of Soils Treated with Cypermethrin  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Sousa, Ana Paula A.; Andre?a, Mara M.

2011-01-01

112

Greenhouse-gas emissions from soils increased by earthworms  

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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...

2013-01-01

113

Genetic adaptation of earthworms to copper pollution: is adaptation associated with fitness costs in Dendrobaena octaedra?  

Science.gov (United States)

Exposure to copper pollution affects reproduction, growth and survival of earthworms. It is known that earthworms can cope with high copper burdens, but the distinction between physiological acclimation and evolutionary heritable changes and associated fitness consequences of the adaption to long-term copper exposure has rarely been studied. To investigate adaptation of earthworm populations of Dendrobaena octaedra to copper contamination, three populations from polluted soil were studied and compared to three unpolluted reference sites. Adult worms were collected at all six sites and cultured in uncontaminated control soil in the laboratory, where life-history traits were studied and F1-generations were produced. The newly hatched F1-generation worms were placed in uncontaminated control or copper-spiked soil to study if the adaptation was due to acclimation or genetic inheritance. This experiment showed that populations from polluted areas generally had a higher individual growth rate, reduced time to maturity, increased reproduction, and also increased mortality compared to the reference populations in both control and copper-spiked soil. The differences in life-history traits indicate that natural selection has resulted in genetic adaptation to copper pollution in the exposed populations. The population growth rates suggest a weak detrimental effect on population growth rate of being exposed to copper for both type of populations, but no sign of cost. On the contrary, estimates of population growth rates integrating all life-history traits showed that copper adapted populations perform on average relatively better than reference populations in both uncontaminated and copper-spiked soil. PMID:21336825

Fisker, Karina V; Sørensen, Jesper G; Damgaard, Christian; Pedersen, Knud Ladegaard; Holmstrup, Martin

2011-05-01

114

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

Science.gov (United States)

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

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

2014-03-01

115

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

Science.gov (United States)

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

Switzer, Paul V.; Fritz, Ann H.

2001-01-01

116

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

Energy Technology Data Exchange (ETDEWEB)

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

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

1981-09-01

117

Heavy metal concentrations in soil and earthworms in a floodplain grassland  

Energy Technology Data Exchange (ETDEWEB)

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.

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

118

PEM Fuel Cell Freeze Durability and Cold Start Project  

Energy Technology Data Exchange (ETDEWEB)

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.

Patterson, T.; O' Neill, Jonathan

2008-01-02

119

Carbon-Mineral Interactions along an Earthworm Invasion Gradient  

Science.gov (United States)

We broadly agree that the interactions of organic matter and minerals contribute to soils’ capacity to store carbon. Such interactions may be controlled by the processes that determine the availability of organic matter and minerals and their physical contacts. One of these processes is bioturbation, and earthworms are the best known organisms that physically mix soils. We are studying carbon mineral interactions along an approximately 200 meter long earthworm invasion transect in a hardwood forest in northern Minnesota. This transect extends from the soils where earthworms are absent to the soils that have been invaded by earthworms for ~30-40 years. Pre-invasion soils have approximately 5 cm thick litter layer, thin (~5 cm) A horizon, silt rich E horizon, and clay-rich Bt horizons. The A and E horizons formed from aeolian deposits, while the clay-rich Bt horizons developed from glacial till. With the advent of earthworm invasion, the litter layer disappears, and the A horizon thickens at the expense of the E horizons. Carbon and nitrogen concentrations in the A and E horizons significantly increased with the advent of earthworm invasion. Simultaneously, minerals’ capacities to complex the organic matter appear to be greater in the soils with active earthworm populations. Based on the data from the two end member soils along the transect, minerals’ specific surface area in the A and E horizons are larger in the earthworm invaded soil than in the pre-invasion soil. Additionally, earthworm invasion rapidly (within soil mixing at the invaded site. We are currently extending the measurements of carbon, specific surface area, and 210Pb activities to the seven soil pits along the entire length of the transect. This growing data set, when ultimately combined with ongoing monitoring of (1) the population dynamics of earthworms along the transect and (2) dissolved organic carbon, will allow us to answer how and how much soils’ capacity to store carbon are affected by burrowing organisms who are often the key stone species of given ecosystems.

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

2010-12-01

120

Soil and elemental mixing rates across an earthworm invasion chronosequence  

Science.gov (United States)

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

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

2012-12-01

 
 
 
 
121

Response of Nitrous Oxide Flux to Addition of Anecic Earthworms to an Agricultural Field  

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The burrowing and feeding activities of earthworms may have a strong effect on the flux of N2O from agricultural soils. As such, shifts to agricultural management practices that increase the number of earthworms require an understanding of the role of earthworms in N2O dynamics. We conducted a field experiment to examine the effects of addition of anecic earthworms (Lumbricus terrestris) on N

Amador, Jose? A.; Avizinis, Edward J.

2013-01-01

122

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

Salmon, Sandrine; Geoffroy, Jean-jacques; Ponge, Jean-franc?ois

2005-01-01

123

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

Energy Technology Data Exchange (ETDEWEB)

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

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

1992-04-01

124

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

Energy Technology Data Exchange (ETDEWEB)

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

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

1997-05-01

125

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

Science.gov (United States)

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…

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

2009-01-01

126

Literature-derived bioaccumulation models for earthworms: Development and validation  

Energy Technology Data Exchange (ETDEWEB)

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

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

1999-09-01

127

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

Science.gov (United States)

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

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

2011-12-01

128

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

2009-10-15

129

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

2005-01-01

130

Variation in seedling freezing response is associated with climate in Larrea  

Science.gov (United States)

Variation in freezing severity is hypothesized to have influenced the distribution and evolution of the warm desert evergreen genus Larrea. If this hypothesis is correct, performance and survival of species and populations should vary predictably along gradients of freezing severity. If freezing environment changes in the future, the ability of Larrea to adapt will depend on the structure of variation for freezing resistance within populations. To test whether freezing responses vary among and within Larrea populations, we grew maternal families of seedlings from high and low latitude L. divaricata and high latitude L. tridentata populations in a common garden. We measured survival, projected plant area and dark-adapted chlorophyll fluorescence (Fv/Fm) before and after cold acclimation and for 2 weeks following a single freeze. We detected significant variation in freezing resistance among species and populations. Maternal family lines differed significantly in their responses to cold acclimation and/or freezing for two out of the three populations: among L. tridentata maternal families and among low latitude L. divaricata maternal families. There were no significant differences across maternal families of high latitude L. divaricata. Our results indicate that increased freezing resistance in high latitude populations likely facilitated historical population expansion of both species into colder climates, but this may have occurred to a greater extent for L. tridentata than for L. divaricata. Differences in the structure of variation for cold acclimation and freezing responses among populations suggest potential differences in their ability to evolve in response to future changes in freezing severity.

Marshall, Diane L.; Maherali, Hafiz; Pockman, William T.

2013-01-01

131

Hibernation physiology, freezing adaptation and extreme freeze tolerance in a northern population of the wood frog.  

Science.gov (United States)

We investigated hibernation physiology and freeze tolerance in a population of the wood frog, Rana sylvatica, indigenous to Interior Alaska, USA, near the northernmost limit of the species' range. Winter acclimatization responses included a 233% increase in the hepatic glycogen depot that was subsidized by fat body and skeletal muscle catabolism, and a rise in plasma osmolality that reflected accrual of urea (to 106±10 ?mol ml(-1)) and an unidentified solute (to ~73 ?mol ml(-1)). In contrast, frogs from a cool-temperate population (southern Ohio, USA) amassed much less glycogen, had a lower uremia (28±5 ?mol ml(-1)) and apparently lacked the unidentified solute. Alaskan frogs survived freezing at temperatures as low as -16°C, some 10-13°C below those tolerated by southern conspecifics, and endured a 2-month bout of freezing at -4°C. The profound freeze tolerance is presumably due to their high levels of organic osmolytes and bound water, which limits ice formation. Adaptive responses to freezing (-2.5°C for 48 h) and subsequent thawing (4°C) included synthesis of the cryoprotectants urea and glucose, and dehydration of certain tissues. Alaskan frogs differed from Ohioan frogs in retaining a substantial reserve capacity for glucose synthesis, accumulating high levels of cryoprotectants in brain tissue, and remaining hyperglycemic long after thawing. The northern phenotype also incurred less stress during freezing/thawing, as indicated by limited cryohemolysis and lactate accumulation. Post-glacial colonization of high latitudes by R. sylvatica required a substantial increase in freeze tolerance that was at least partly achieved by enhancing their cryoprotectant system. PMID:23966588

Costanzo, Jon P; do Amaral, M Clara F; Rosendale, Andrew J; Lee, Richard E

2013-09-15

132

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

Science.gov (United States)

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 4°C. Mortality occurred in cycles around 0°C in both populations, and little to no mortality occurred at temperatures >0°C. Individuals from both sources held in diel 0°C 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.

Moffitt, Christine M.; James, Christopher A.

2012-01-01

133

Genotoxic effects of glyphosate or paraquat on earthworm coelomocytes.  

Science.gov (United States)

The potential genotoxicity (nuclear anomalies, damage to single-strand DNA) and pinocytic adherence activity of two (glyphosate-based and paraquat-based) commercial herbicides to earthworm coelomocytes (immune cells in the coelomic cavity) were assessed. Coelomocytes were extracted from earthworms (Pheretima peguana) exposed to concentrations glyphosate-based or paraquat-based herbicides on filter paper for 48 h. Three assays were performed: Micronucleus (light microscopy count of micronuclei, binuclei, and trinuclei), Comet (epifluorescent microscope and LUCIA image analyzer measure of tail DNA %, tail length, and tail moment), and Neutral Red (to detect phagocytic or pinocytic activity). The LC50 value for paraquat was 65-fold lower than for glyphosate indicating that paraquat was far more acutely toxic to P. peguana. There were significant (P glyphosate at 25 × 10(-1) (10(-3) LC50) and paraquat at 39 × 10(-5) (10(-4) LC50) ?g cm(-2) filter paper. In earthworms exposed to glyphosate, no differences in tail DNA%, tail length, and tail moment of coelomocytes were detected. In contrast, for paraquat at 10(-1) LC50 concentration, there were significant (P glyphosate or paraquat at 10(-3) LC50 concentration. This study showed that, at concentrations well below field application rates, paraquat induces both clastogenic and aneugenic effects on earthworm coelomocytes whereas glyphosate causes only aneugenic effects and therefore does not pose a risk of gene mutation in this earthworm. PMID:22644885

Muangphra, Ptumporn; Kwankua, Wimon; Gooneratne, Ravi

2014-06-01

134

Interactions between residue placement and earthworm ecological strategy affect aggregate turnover and N2O dynamics in agricultural soil  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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

Giannopoulos, G.; Pulleman, M. M.; Groenigen, J. W.

2010-01-01

135

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

Science.gov (United States)

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

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

2014-08-01

136

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)

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

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

2012-01-17

137

Interactions of intracellular calcium and immune response in earthworms  

Directory of Open Access Journals (Sweden)

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 earthworm’s innate immunity.

P Engelmann

2011-05-01

138

Soil contamination evaluations: Earthworms as indicators of soil quality  

Energy Technology Data Exchange (ETDEWEB)

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.

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

1995-12-31

139

Accumulation of chlorinated benzenes in earthworms  

Energy Technology Data Exchange (ETDEWEB)

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

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

1996-12-31

140

Metabolic changes in Avena sativa crowns recovering from freezing.  

Science.gov (United States)

Extensive research has been conducted on cold acclimation and freezing tolerance of fall-sown cereal plants due to their economic importance; however, little has been reported on the biochemical changes occurring over time after the freezing conditions are replaced by conditions favorable for recovery and growth such as would occur during spring. In this study, GC-MS was used to detect metabolic changes in the overwintering crown tissue of oat (Avena sativa L.) during a fourteen day time-course after freezing. Metabolomic analysis revealed increases in most amino acids, particularly proline, 5-oxoproline and arginine, which increased greatly in crowns that were frozen compared to controls and correlated very significantly with days after freezing. In contrast, sugar and sugar related metabolites were little changed by freezing, except sucrose and fructose which decreased dramatically. In frozen tissue all TCA cycle metabolites, especially citrate and malate, decreased in relation to unfrozen tissue. Alterations in some amino acid pools after freezing were similar to those observed in cold acclimation whereas most changes in sugar pools after freezing were not. These similarities and differences suggest that there are common as well as unique genetic mechanisms between these two environmental conditions that are crucial to the winter survival of plants. PMID:24675792

Henson, Cynthia A; Duke, Stanley H; Livingston, David P

2014-01-01

 
 
 
 
141

Metabolic Changes in Avena sativa Crowns Recovering from Freezing  

Science.gov (United States)

Extensive research has been conducted on cold acclimation and freezing tolerance of fall-sown cereal plants due to their economic importance; however, little has been reported on the biochemical changes occurring over time after the freezing conditions are replaced by conditions favorable for recovery and growth such as would occur during spring. In this study, GC-MS was used to detect metabolic changes in the overwintering crown tissue of oat (Avena sativa L.) during a fourteen day time-course after freezing. Metabolomic analysis revealed increases in most amino acids, particularly proline, 5-oxoproline and arginine, which increased greatly in crowns that were frozen compared to controls and correlated very significantly with days after freezing. In contrast, sugar and sugar related metabolites were little changed by freezing, except sucrose and fructose which decreased dramatically. In frozen tissue all TCA cycle metabolites, especially citrate and malate, decreased in relation to unfrozen tissue. Alterations in some amino acid pools after freezing were similar to those observed in cold acclimation whereas most changes in sugar pools after freezing were not. These similarities and differences suggest that there are common as well as unique genetic mechanisms between these two environmental conditions that are crucial to the winter survival of plants.

Henson, Cynthia A.; Duke, Stanley H.; Livingston, David P.

2014-01-01

142

The survival of mouse oocytes shows little or no correlation with the vitrification or freezing of the external medium, but the ability of the medium to vitrify is affected by its solute concentration and by the cooling rate.  

Science.gov (United States)

As survival of mouse oocytes subjected to vitrification depends far more on the warming rate than on the cooling rate, we wished to determine whether the lack of correlation between survival and cooling rate was mirrored by a lack of correlation between cooling rate and vitrification of the medium (EAFS), and between survival and the vitrification of the medium. The morphological and functional survival of the oocytes showed little or no relation to whether or not the EAFS medium vitrified or froze. We studied if the droplet size and the elapsed time (between placing the droplet on the Cryotop and the start of cooling) affects the result through modification of the cooling rate and solute concentration. Dehydration was rapid; consequently, the time between the placing the droplets into a Cryotop and cooling must be held to a minimum. The size of the EAFS droplet that is being cooled does not seem to affect vitrification. Finally, the degree to which samples of EAFS vitrify is firmly dependent on both its solute concentration and the cooling rate. PMID:24056038

Paredes, Estefania; Mazur, Peter

2013-12-01

143

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

Directory of Open Access Journals (Sweden)

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 60°C 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.

Y. Kooch

2008-01-01

144

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.

2012-10-01

145

Heavy metal concentrations in earthworms from soil amended with sewage slude  

Energy Technology Data Exchange (ETDEWEB)

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

Beyer, W.N. (United States Fish and Wildlife Service, Laurel, MD); Chaney, R.L.; Mulhern, B.M.

1982-07-01

146

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

Directory of Open Access Journals (Sweden)

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 2008–2009 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 (0–2 cm soil depth oribatid mites was 1–2 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.

John C. Maerz

2011-03-01

147

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

Science.gov (United States)

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

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

2012-12-01

148

Diversity and host specificity of the Verminephrobacterâ??earthworm symbiosis  

DEFF Research Database (Denmark)

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 0.012â??0.026 substitutions per site per 50 million years and thus similar to rates reported from other symbiotic bacteria.

Lund, Marie Braad; Davidson, Seana

2010-01-01

149

Freeze-Tolerant Condensers  

Science.gov (United States)

Two condensers designed for use in dissipating heat carried by working fluids feature two-phase, self-adjusting configurations such that their working lengths automatically vary to suit their input power levels and/or heat-sink temperatures. A key advantage of these condensers is that they can function even if the temperatures of their heat sinks fall below the freezing temperatures of their working fluids and the fluids freeze. The condensers can even be restarted from the frozen condition. The top part of the figure depicts the layout of the first condenser. A two-phase (liquid and vapor) condenser/vapor tube is thermally connected to a heat sink typically, a radiatively or convectively cooled metal panel. A single-phase (liquid) condensate-return tube (return artery) is also thermally connected to the heat sink. At intervals along their lengths, the condenser/vapor tube and the return artery are interconnected through porous plugs. This condenser configuration affords tolerance of freezing, variable effective thermal conductance (such that the return temperature remains nearly constant, independently of the ultimate sink temperature), and overall pressure drop smaller than it would be without the porous interconnections. An additional benefit of this configuration is that the condenser can be made to recover from the completely frozen condition either without using heaters, or else with the help of heaters much smaller than would otherwise be needed. The second condenser affords the same advantages and is based on a similar principle, but it has a different configuration that affords improved flow of working fluid, simplified construction, reduced weight, and faster recovery from a frozen condition.

Crowley, Christopher J.; Elkouhk, Nabil

2004-01-01

150

Water Freezing in Nanopores  

International Nuclear Information System (INIS)

Full text: The structure and dynamics of supercooled liquid water and of amorphous ice is a very active area of current research. Confinement induces new phenomena such as melting point suppression, and in some cases, water seems even not to freeze at all, as shown in recent differential scanning calorimetry (DSC) measurements. Micelle-templated porous silica materials, such as SBA-15 and MCM-41represent ideal model systems for studying water in nano-confinement. The pores of these materials are perfectly ordered on a two-dimensional hexagonal lattice with lattice parameter of a few Nanometers, making these materials ideal for investigations with small-angle X-ray (SAXS) and neutron (SANS) scattering methods. We performed Synchrotron-SAXS and SANS measurement on water-filled MCM-41 and SBA-15 porous materials with pore diameters ranging from 2 nm - 9 nm. The advantages of the two complementary scattering techniques, SAXS and SANS are ideally applied to our system. The high brilliance synchrotron radiation makes strain effects in the order of 10-3 resolvable. The phase contrast variation in neutron scattering allows a detailed investigation of density change of water by using a proper H2O/D2O. Two phenomena could be observed during freezing and melting of confined water. First, the water density change during phase transformation results in change of the scattering contrast and therefore changes the scattering intensity. Second, the strain-induced contraction and expansion of the pore lattice during water phase transformation leads to a shift of the Bragg-Peak position. Both effects are observed for water in large pores exactly at the phase transition temperatures predicted by DSC. Moreover, these effects are present even for water confined in pores below 2,5 nm where water is assumed not to freeze. Additionally, we performed cooling and heating cycles on samples with different pore filling fractions. Different number of the few water layers on pore walls show different freezing and melting behaviour which is discussed together with the results from fully-filled pores with different diameters. (author)

2010-09-06

151

Freezing Human ES Cells  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Here we demonstrate how our lab freezes HuES human embryonic stem cell lines. A healthy, exponentially expanding culture is washed with PBS to remove residual media that could otherwise quench the Trypsin reaction. Warmed 0.05% Trypsin-EDTA is then added to cover the cells, and the plate allowed to incubate for up to 5 mins at room temperature. During this time cells can be observed rounding, and colonies lifting off the plate surface. Gentle repeated pipetting will remove cells and colon...

Trish, Erin; Dimos, John; Eggan, Kevin

2006-01-01

152

Freezing parameters of soft spheres  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 bein...

2009-01-01

153

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

1986-01-01

154

Influence of earthworm humus on sweet potato yield  

Directory of Open Access Journals (Sweden)

Full Text Available The Paraíba State is the higher producer of the northeast region and the fourth brazilian producer of sweet potato, where this crop has a very fodder, economic and social importance, promoting the creation of joy and rent, as well contributing for the fixation of man on rural zone. The purpose of the experiment was to evaluate the influence of organic fertilization on components of production and productivity of sweet potato. The experiment was carried out from May to September of 2005, at State of Paraíba, Brazil. The experimental design was randomized blocks with six treatments (0; 3; 6; 9; 12 and 15 t ha-1 of earthworm humus, in four replications. The evaluated variables were total and marketable roots number, raw yield and total and marketable yield of roots. The maximum total yield of roots, of commercial and non-commercial roots of sweet potato, estimated by models (curves were respectively 18.76; 16.29 and 2.46 t ha-1, obtained with a dosage of 15.00 t ha-1 of earthworm humus. The maximum yield of raw sweet potato-estimated the equation was 12.82 t ha-1 obtained with 15 t ha-1 of the earthworm humus. The application of 15 t ha-1 of earthworm humus increased from 9.96 t ha-1 (109.69% and 8.50 t ha-1 (105.20% in total yield and commercial roots sweet potato, respectively, in relation to the treatment without fertilizer. For every R$ 1.00 invested in earthworm humus there was a return of R$ 2.17 from the sale of sweet potato roots.Key-words: Ipomoea batatas, organic fertilization, root production.

Marinevea Medeiros de Oliveira

2009-08-01

155

Performance Characteristics of an Isothermal Freeze Valve  

Energy Technology Data Exchange (ETDEWEB)

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.

Hailey, A.E.

2001-08-22

156

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

157

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

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

2011-01-01

158

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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

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

1997-01-01

159

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

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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...

1995-01-01

160

Accumulation of methylmercury in the earthworm, Eisenia foetida, and its effect on regeneration  

Energy Technology Data Exchange (ETDEWEB)

Earthworms provide an appropriate model for evaluating the environmental hazards of metals in soil, and they are also excellent organisms for studying the process of regeneration. Two studies have found that concentrations of mercury in earthworms were higher than those in the soil where they lived. This study investigates the accumulation of methylmercury in the earthworm, Eisenia foetida (Savigny), and its effect on regeneration after excision of the caudal end.

Beyer, W.N.; Cromartie, E.; Moment, G.B.

1985-08-01

 
 
 
 
161

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 un...

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

2009-01-01

162

Phosphoglycerate kinase 1 expression responds to freezing, anoxia, and dehydration stresses in the freeze tolerant wood frog, Rana sylvatica.  

Science.gov (United States)

Natural freezing survival by wood frogs (Rana sylvatica) involves multiple organ-specific changes in gene expression. Screening of a cDNA library made from brain of frozen frogs revealed freeze-responsive up-regulation of the glycolytic enzyme, phosphoglycerate kinase 1 (PGK1). Northern blots showed an approximately two-fold increase in pgk1 transcripts in brain of frozen frogs whereas PGK1 protein levels rose by three- to five-fold within 4-8 hr of freezing. Freezing also elevated pgk1 transcripts in liver but not in skin. Both transcript and protein levels also rose in response to two of the component stresses of freezing (anoxia and dehydration) with a particularly pronounced (11-fold) increase in PGK1 protein in brain in response to anoxia. Amino acid sequence analysis showed 92.5% identity between wood frog and Xenopus laevis PGK1 and 86-88% identity with the zebrafish, chicken, and human protein. Four unique amino acid substitutions in the wood frog protein could be important in maintaining the functional conformation of the wood frog protein at low body temperatures. Elevated amounts of PGK1, one of the ATP-generating reactions of glycolysis, in wood frog brain during freezing would enhance the glycolytic capacity of the organ and support the maintenance of cellular energetics under the ischemic conditions of the frozen state. PMID:18785212

Wu, Shaobo; Storey, Janet M; Storey, Kenneth B

2009-01-01

163

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.

2011-10-01

164

The effect of conservation farming on the abundance of earthworms on eroded soils  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The soil of the experimental site is (JIb-el) Eutric Albeluvisol (Abe-el) with a texture of loamy sand at footslopes and clay loam at top part of the slopes. The population density of earthworms (Lumbricidae) on slope soil was the lowest after winter wheat, which was the first crop in the rotation (38 earthworms m-2 ) and the highest after the second crop - spring barley (77 earthworms m-2) and after the third crop - oats (61 earthworms m-2). Through the soil conservation technology - disking...

Kinderiene?, Irena

2006-01-01

165

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

Directory of Open Access Journals (Sweden)

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..

M Grdiša

2013-04-01

166

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

167

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

Science.gov (United States)

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

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

2013-03-01

168

Earthworm responses to Cd and Cu under fluctuating environmental conditions: a comparison with results from laboratory exposures  

International Nuclear Information System (INIS)

Laboratory toxicity tests are usually conducted under stable ambient conditions, while exposures in ecosystems occur in a fluctuating climate. To assess how climate influences the toxicity of Cu and Cd for the earthworm Lumbricus rubellus, this study compared effects for life-cycle parameters (survival, reproduction), cellular status (lysosomal membrane stability), gene expression (transcript of the metal binding protein metallothionein-2) and tissue metal concentration measured under outdoor conditions, with the same responses under constant conditions as measured by Spurgeon et al. [Spurgeon, D.J., Svendsen, C., Weeks, J.M., Hankard, P.K., Stubberud, H.E., Kammenga, J.E., 2003. Quantifying copper and cadmium impacts on intrinsic rate of population increase in the terrestrial oligochaete Lumbricus rubellus. Environmental Toxicology and Chemistry 22, 1465-1472]. Both metals were found to significantly influence earthworm reproduction, compromise lysosomal membrane stability and induce MT-2 gene expression in the outdoor system. Comparison with physiological and life-cycle responses in the laboratory indicated similar response patterns and effect concentrations for Cu. For Cd, lysosomal membrane stability and MT-2expression showed comparable responses in both exposures. Juvenile production rate, however, gave different dose response relationships, with the EC-50 in the outdoor test approximately half that in the laboratory test. A difference in Cd accumulation was also seen. Overall, however, the comparison indicated only a marginal effect of environmental fluctuations typical for northern temperate Europe on earthworm sensitivity to the two metals. - Comparative analysis of life-cycle, physiological and molecular responses to Cu and Cd indicate similar responses under static and fluctuating climate regimes

2005-08-01

169

UO2 flow freezing processes  

International Nuclear Information System (INIS)

Transient freezing of molten UO2 and UO2-steel mixtures in steel channels is an important functional heat transfer process which occurs in the course of Liquid Metal-Cooled Fast Breeder Reactor (LMFBR) Hypothetical Core Disruptive Accidents (HCDA). Fuel freezing processes can influence both the transient overpower (TOP) and transient undercooling (TUC) accidents. In the absence of freezing, either fuel sweepout or continuous fuel removal can lead to shutdown with a largely coolable geometry in the TOP case and greatly reduce concerns over recriticality in the TUC case. However, with fuel freezing either case may lead to a temporarily ''bottled-up core'' condition which is relieved by melting of the initially formed plugs. Whether further freezing occurs in either the upward or downward direction through the core support structure is of interest in determining the decay heat level for Post-Accident Heat Removal (PAHR). Attention is focused on the freezing of ceramic fuel in steel channels. A discussion of the conduction-controlled and bulk freezing mechanisms is given first. A fuel crust stability criterion is proposed, and an explicit formula providing a rough estimate of critical fuel crust disintegration conditions is developed. A comparison of the crust stability criterion with a number of explanatory experimental results is made. A steel ablation-fuel freezing mechanism is identified. If the conditions in the fuel flow are such to prevent fuel crust growth, then the steel wall melting can become catastrophic. Steel ablation rapidly leads to fuel freezing in a bulk manner via turbulent mixing between the relatively ''cold'' molten steel and hot molten fuel. Based on this ablation-freezing concept, simple equations are developed for molten fuel penetration into steel channels. Comparison of the equations with the available experimental results proves favorable

1977-01-01

170

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

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Earthworm activity is known to increase emissions of nitrous oxide (N2O) from arable soils. Earthworm gut, casts, and burrows have exhibited higher denitrification activities than the bulk soil, implicating priming of denitrifying organisms as a possible mechanism for this effect. Furthermore, the earthworm feeding strategy may drive N2O emissions, as it determines access to fresh organic matter for denitrification. Here, we determined whether interactions between earthworm feeding strategy a...

Nebert, L. D.; Bloem, J.; Lubbers, I. M.; Groenigen, J. W.

2011-01-01

171

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

Earthworm activity is known to increase emissions of nitrous oxide (N2O) from arable soils. Earthworm gut, casts, and burrows have exhibited higher denitrification activities than the bulk soil, implicating priming of denitrifying organisms as a possible mechanism for this effect. Furthermore, the earthworm feeding strategy may drive N2O emissions, as it determines access to fresh organic matter for denitrification. Here, we determined whether interactions between earthworm feeding strategy a...

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

2011-01-01

172

Earthworm activities in cassava and egusi melon fields in the transitional zone of Benin: linking farmers' perceptions with field studies  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Farmers' perceptions of earthworm activities were studied in the transitional zone of Benin and linked to scientific explanations of earthworm casting activities. Earthworm activity was assessed in farmers' fields with three different cassava cultivars and in a field experiment with three different egusi melon species. The experiment included plots with cowpea and maize. The study also comprised group discussions and a survey with 91 individual farmers. All farmers were aware of earthworms, b...

2008-01-01

173

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

2007-05-01

174

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

Directory of Open Access Journals (Sweden)

Full Text Available 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 manure, (2 filter cake of sugar mill, (3 sugarcane trash, (4 mixture of cattle manure+filter cake, and (5 mixture of cattle manure+sugarcane trash. There were three application rates of the organic matter (5, 10, and 15 ton ha-1. The treatments were arranged in factorial block randomize design with three replications and one treatment as a control (no organic input. Earthworms were collected using monolith sampling methods and hand-sorted from each plot, and measured its density (D (indiv.m-2, biomass (B (g m-2 and B/D ratio (g/indiv.. All the plots receiving organic matter input had higher earthworm density, biomass, and B/D ratio than the control. The highest earthworm population density was found in the plot receiving application of sugarcane trash (78 indiv.m-2 and the mixture of cattle manure+sugarcane trash (84 indiv.m-2. The increase in application rates of organic matter could increase the earthworm density and biomass. Earthworm population density also appeared to be strongly influenced by the quality of organic matter, such as the C-organic, N, C/N ratio, lignin, polyphenols, and cellulose content. Earthworm preferred low quality organic matter. It was caused by the higher energy of low quality organic matter than high quality organic matter. Our findings suggest that the input of low quality organic matter with application rate as 10 ton ha-1 is important for maintaining earthworm population and soil health in sugarcane land.

Nurhidayati Nurhidayati

2012-12-01

175

Intensified Weathering Control of Carbon Cycle along an Earthworm Invasion Chronosequence: Preliminary Data  

Science.gov (United States)

Though earthworms may appear ubiquitous and native where they are found, this is not true in the Glaciated areas of North America. After the glacial retreat, earthworms were not able to catch up with the northward expansion of forests. Subsequently, these forests in the glaciated areas have developed without native earthworm species over the past six to ten thousand years. With the arrival of agriculture, fishing villages, and expansion of unpaved roads, exotic earthworm species began to invade the adjacent forests. We focus on a well studied earthworm invasion chronosequence in the Chippewa National Forest in Minnesota. The chronosequence is ~100 meter long, which represents several decades of invasion history. In general, O horizon dwelling species form the pioneering population and remove the litter layer. Subsequently, shallow soil mixers are followed by deep burrowing species. As the invasion front advances, O horizons disappear, A horizons become thicker, underlying sandy aeolian blankets are incorporated into the A horizons, and there is an increasingly frequent signs of earthworm burrows in the clay rich Bt horizons. Our preliminary data was from two end members of the chronosequence. Earthworm-driven soil mixing created more vertically homogeneous profiles of elemental compositions. Probably reflecting the upward incorporation of clay and iron-oxide rich Bt horizon materials by earthworms. A horizons in the invaded site were more enriched not only in total Fe and Al but also in crystalline and amorphous forms of iron and aluminum oxides than in the non-invaded soil. Particularly, sodium pyrophosphate extracted pools of Fe and Al, which represent the organically complexed Fe and Al oxides, were significantly greater in the invaded A horizon. This suggests that the iron and aluminum oxides translocated upward by earthworms may help complexing and thus stabilizing organic carbon. Therefore underground invasion of earthworms may significantly intensify the coupling of chemical weathering and soil carbon cycle. Our ultimate goal is to understand the holistic response of mineral weathering and carbon cycle to accelerated soil mixing by earthworm invasion.

Fernandez, C.; Yoo, K.; Aufdenkampe, A. K.; Hale, C.

2009-12-01

176

NUTRITIONAL AND ANTIOXIDANT EVALUATION OF EARTHWORM POWDER (Eudrillus euginae  

Directory of Open Access Journals (Sweden)

Full Text Available Studies have been made to understand the nutritional, aminoacids and antioxidant concentrations in the dried powder of Eudrillus euginae, an African soil dweller. The nutritional factors such as carbohydrate, glucose, total free aminoacids, protein, vitamin A, and total phenol were determined. The individual aminoacids includes Histidine, Serine, Arginine, Methionine, Proline, Tryptophan, and Lysine was also quantified. The enzymatic antioxidants, such as Glutathione S transferase (GST, Glutathione reductase (GR, Glutathione Peroxidase (GPx, Superoxide Dismutase (SOD and Catalase (CAT and the non-enzymatic antioxidant like Reduced Glutathione (GSH, Vitamin C and Vitamin E were assayed. The findings of the present study reveals that the earthworm is rich in protein, carbohydrate, fat and rich antioxidants suggest that this earthworm can be used as animal protein with good source of antioxidants.

J. Anitha

2012-02-01

177

Riboflavin content in autofluorescent earthworm coelomocytes is species-specific.  

Directory of Open Access Journals (Sweden)

Full Text Available We have recently shown that a large proproportion of earthworm coelomocytes exhibit strong autofluorescence in some species (Dendrobaena veneta, Allolobophora chlorotica, Dendrodrilus rubidus, Eisenia fetida, and Octolasion spp., while autofluorescent coelomocytes are very scarce in representatives of Lumbricus spp. and Aporrectodea spp. Riboflavin (vitamin B2 was identified as a major fluorophore in Eisenia jetida coelomocytes. The main aim of the present experiments was to quantify riboflavin content in autofluorescent coelomocytes (eleocytes from several earthworm species through a combination of flow cytometric and spectrofluorometric measurements. Spectrofluorometry of coelomocyte lysates showed that riboflavin was non-detectable in the coelomocytes of Aporrectodea spp. and Lumbricus spp., but was a prominent constituent of lysates from species with autofluorescent eleocytes. In the latter case, riboflavin content was the highest in E. fetida, followed by Octolasion spp. > A. chlorotica > D. rubidus. The riboflavin content of coelomocytes correlates positively with eleocyte autofluorescence intensity measured by flow cytometry and visible with fluorescence microscopy.

Joanna Homa

2007-01-01

178

Using Flow Cytometry to Measure Phagocytic Uptake in Earthworms  

Directory of Open Access Journals (Sweden)

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.

Sheryl L. Fuller-Espie

2010-12-01

179

Unearthing the genome of the earthworm Lumbricus rubellus  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Elsworth, Benjamin Lloyd

2013-01-01

180

PREDICTION OF BIOAVAILABILITY OF CHLORPYRIFOS RESIDUES IN SOIL TO EARTHWORMS  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ear...

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

2011-01-01

 
 
 
 
181

The ecology and control of earthworms on golf courses  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Bartlett, Mark D.

2006-01-01

182

Biosynthesis of luminescent quantum dots in an earthworm  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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(1), superparamagnetic cobalt-platinum alloy nanowires(2) and gold-cobalt oxide nanowires(3) 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 cadmi...

Stuerzenbaum, S. R.; Hoeckner, 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

183

Using Flow Cytometry to Measure Phagocytic Uptake in Earthworms†  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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

Fuller-espie, Sheryl L.

2010-01-01

184

Effects of Earthworms on Phosphorus Dynamics – A Review  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Belowground biotic interactions are known to influence soil fertility and plant growth by changing the physical environment and the soil nutrient cycles. Among the great diversity of soil biota, earthworms are keystone soil organisms in regulating nutrient cycling through: (i) their own metabolism that leads to high availability of carbon (C) and nitrogen (N) from metabolic wastes such as urine, mucus and tissue, (ii) the dispersal and the stimulation of soil microorganism activity associated...

Le Bayon, Rene?e-claire; Milleret, Roxane

2009-01-01

185

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Stojanovi? Mirjana M.; Karaman Spasenija D.

2003-01-01

186

Riboflavin content in autofluorescent earthworm coelomocytes is species-specific.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We have recently shown that a large proproportion of earthworm coelomocytes exhibit strong autofluorescence in some species (Dendrobaena veneta, Allolobophora chlorotica, Dendrodrilus rubidus, Eisenia fetida, and Octolasion spp.), while autofluorescent coelomocytes are very scarce in representatives of Lumbricus spp. and Aporrectodea spp. Riboflavin (vitamin B2) was identified as a major fluorophore in Eisenia jetida coelomocytes. The main aim of the present experiments was to quantify ribofl...

2007-01-01

187

Earthworms newly from Mongolia (Oligochaeta, Lumbricidae, Eisenia)  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 Bou...

2013-01-01

188

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.)

1982-01-01

189

PREDICTION OF BIOAVAILABILITY OF CHLORPYRIFOS RESIDUES IN SOIL TO EARTHWORMS  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: English Abstract in english 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.

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

190

PREDICTION OF BIOAVAILABILITY OF CHLORPYRIFOS RESIDUES IN SOIL TO EARTHWORMS  

Directory of Open Access Journals (Sweden)

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.

X.M Wu

2011-01-01

191

Comparative Genomics of Symbiotic Bacteria in Earthworm Nephridia  

DEFF Research Database (Denmark)

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.

Kjeldsen, Kasper Urup; Pinel, Nicolas

192

Short-term stabilization of grape marc through earthworms.  

Science.gov (United States)

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

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

2011-03-15

193

Modeling of the accumulation of organic lipophilic chemicals in earthworms  

Energy Technology Data Exchange (ETDEWEB)

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.

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

194

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

DEFF Research Database (Denmark)

Cold tolerance and metabolic responses to freezing of three slug species common in Scandinavia (Arion ater, Arion rufus and Arion lusitanicus) are reported. Autumn collected slugs were cold acclimated in the laboratory and subjected to freezing conditions simulating likely winter temperatures in 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 freezing at -2 °C. (1)H NMR spectroscopy revealed that freezing of body fluids resulted in accumulation of lactate, succinate and glucose. Accumulation of lactate and succinate indicates that ATP production occurred via fermentative pathways, which is likely a result of oxygen depletion in frozen tissues. 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.

Slotsbo, Stine; Hansen, Lars Monrad

2012-01-01

195

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

Science.gov (United States)

Cold tolerance and metabolic responses to freezing of three slug species common in Scandinavia (Arion ater, Arion rufus and Arion lusitanicus) are reported. Autumn collected slugs were cold acclimated in the laboratory and subjected to freezing conditions simulating likely winter temperatures in 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 freezing at -2 °C. (1)H NMR spectroscopy revealed that freezing of body fluids resulted in accumulation of lactate, succinate and glucose. Accumulation of lactate and succinate indicates that ATP production occurred via fermentative pathways, which is likely a result of oxygen depletion in frozen tissues. Glucose increased from about 6 to 22 ?g/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. PMID:22248916

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

2012-04-01

196

Variation in seedling freezing response is associated with climate in Larrea.  

Science.gov (United States)

Variation in freezing severity is hypothesized to have influenced the distribution and evolution of the warm desert evergreen genus Larrea. If this hypothesis is correct, performance and survival of species and populations should vary predictably along gradients of freezing severity. If freezing environment changes in the future, the ability of Larrea to adapt will depend on the structure of variation for freezing resistance within populations. To test whether freezing responses vary among and within Larrea populations, we grew maternal families of seedlings from high and low latitude L. divaricata and high latitude L. tridentata populations in a common garden. We measured survival, projected plant area and dark-adapted chlorophyll fluorescence (F (v) /F (m)) before and after cold acclimation and for 2 weeks following a single freeze. We detected significant variation in freezing resistance among species and populations. Maternal family lines differed significantly in their responses to cold acclimation and/or freezing for two out of the three populations: among L. tridentata maternal families and among low latitude L. divaricata maternal families. There were no significant differences across maternal families of high latitude L. divaricata. Our results indicate that increased freezing resistance in high latitude populations likely facilitated historical population expansion of both species into colder climates, but this may have occurred to a greater extent for L. tridentata than for L. divaricata. Differences in the structure of variation for cold acclimation and freezing responses among populations suggest potential differences in their ability to evolve in response to future changes in freezing severity. PMID:22068319

Medeiros, Juliana S; Marshall, Diane L; Maherali, Hafiz; Pockman, William T

2012-05-01

197

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

DEFF Research Database (Denmark)

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.

Bruus, Marianne; Bjerre, Arne

1991-01-01

198

Exotic earthworm effects on hardwood forest floor, nutrient availability and native plants: a mesocosm study.  

Science.gov (United States)

A greenhouse mesocosm experiment, representing earthworm-free North American Acer-dominated forest floor and soil conditions, was used to examine the individual and combined effects of initial invasion by three European earthworm species (Dendrobaena octaedra, Lumbricus rubellus and Lumbricus terrestris) on the forest floor and upper soil horizons, N and P availability, and the mortality and biomass of four native understory plant species (Acer saccharum, Aquilegia canadensis, Aralia racemosa, and Carex pensylvanica). All the three earthworm species combined caused larger impacts on most variables measured than any single earthworm species. These included loss of O horizon mass, decreased thickness of the O horizon and increased thickness of the A horizon, and higher availability of N and P. The latter finding differs from field reports where nutrients were less available after invasion, and probably represents an initial transient increase in nutrient supply as earthworms consume and incorporate the O horizon into the A horizon. Earthworms also increased mortality of plants and decreased total mesocosm plant biomass, but here the impact of all the three earthworm species was no greater than that of L. terrestris and/or L. rubellus alone. This study corroborates field studies that European earthworm invasions alter North American forest ecosystem processes by initiating a cascade of impacts on plant community composition and soil properties. PMID:18066602

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

2008-03-01

199

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

Science.gov (United States)

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

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

2014-01-01

200

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

Directory of Open Access Journals (Sweden)

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 44°C. 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 28°C. Afterwards, with the increase in the temperature from 28 to 42°C, 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.

G Tripathi

2011-08-01

 
 
 
 
201

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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 44°C. 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 28°C. Afterwards, with the increase in the temperature from 28 to 42°C, 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.

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

202

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

Energy Technology Data Exchange (ETDEWEB)

Phagocytosis, a host-defense mechanism phylogenetically conserved throughout the animal kingdom, by earthworm (Lumbricus terrestris) coelomocytes has potential as a surrogate for vertebrates to be used as an environmentally acceptable endpoint to assess sublethal immunotoxic risks of contaminated soils to environmental (eg. higher wildlife) and public health. Coelomocytes can be exposed in vivo to complex contaminated parent soils by placing earthworms in situ at hazardous waste sites (HWS) or into soil samples and their dilutions with artificial soil (AS) in the laboratory, or in vitro to soil extracts and their fractionations. Here the authors report on phagocytosis by coelomocytes in earthworms exposed to pentachlorophenol (PCP) contaminated soils from a wood treatment HWS, PCP-spiked AS and PCP treated filter paper (FP). HWS soil was diluted to 25% with AS to a sublethal concentration (ca. 125 mg kg{sup {minus}1}) and earthworms exposed for 14d at 10 C under light conditions. AS was spiked at ca. 125 mg kg{sup {minus}1} PCP and earthworms were similarly exposed. Controls for both consisted of earthworms exposed to 100% AS. Earthworms were exposed to FP treated with a sublethal PCP concentration (15 {micro}g cm{sup {minus}2}) at 10 C under dark conditions for 96H. Controls were similarly exposed without PCP. Phagocytosis by coelomocytes in earthworms exposed to HWS soil, spiked AS and treated FP was suppressed 37, 41 and 29%, respectively. Results are discussed in terms of PCP body burdens and exposure protocols.

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

1995-12-31

203

Abundance of earthworms in Nigerian ecological zones: implications for sustaining fertilizer-free soil fertility  

Directory of Open Access Journals (Sweden)

Full Text Available The abundance of earthworms in the ecological zones in Nigeria has been determined and the possibility of earthworm functions replacing both mechanized land preparation and organic fertilizers discussed. The most abundant earthworms, comprising 62 % of the population, were the advantageous solid-wormcast makers. Mixed Leguminous Wooded Savanna had the highest earthworm density (1.50 million worms/ha, while Wooded Savanna had the lowest (0.23 million worms/ha. Coastal Forest and Mangrove (0.51 t/ha had the highest earthworm biomass and Afziela  Savanna/Semi-Deciduous Forest (0.03 t/ha had the least. A new soil impact index (SIINDEX is introduced, which simultaneously incorporates both earthwormbiomass and density. The highest SIINDEX was from Mixed Leguminous Wooded Savanna (0.72 and the lowest from Afziella Savanna/Semi-Deciduous Forest (0.11. Forests with SIINDEX less than 0.2 should be regarded as endangered, because their earthworm functions are too low to accomplish significant leaf-litter breakdown and recycling. We suggest that if the illegal annual bush burning is prevented, the soil surface will be naturally mulched,earthworms protected, and by their function in the soil, the need for soil mechanization and  fertilization could be replaced by earthworms to produce natural foods

S.O.A. Morafa

2011-10-01

204

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Costa Rica | Language: English Abstract in english 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.

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

205

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

Directory of Open Access Journals (Sweden)

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 collected from different sites on the campus of the University of Agriculture, Abeokuta, Nigeria. The samples were collected between April and November, 2002. Numbers of microorganisms were higher in castings and gut sections than in 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.

A. B Idowu

2006-03-01

206

Bilateral nuclear-weapon freeze  

Energy Technology Data Exchange (ETDEWEB)

In many of the current elections in the U.S. there is a referendum on whether to urge a halt in the production of new nuclear weapons and delivery systems. The nature of such a freeze is discussed here.

Forsberg, R.

1983-01-01

207

FREEZE DRYING PROCESS: A REVIEW  

Directory of Open Access Journals (Sweden)

Full Text Available 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.

Soham Shukla

2011-12-01

208

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

Energy Technology Data Exchange (ETDEWEB)

The information on fluorides (F)-pollution of soil invertebrates is sparse and only a few recent publications deal with F accumulation in some taxonomic groups of soil fauna. Earthworms in particular become the focus of soil-soil fauna interactions in F-polluted sites, even more so since a significant relationship between soil pollution and F load in earthworms was observed. Earthworms coat their burrowings and this may be a mechanism of F-dissemination and subsoil contamination. Evidence is growing that fluorides pass through food chains. Earthworms as the preferred prey of a wide range of animals are therefore in the center of interest as a possible way of F-bioaccumulation in higher trophic levels. For a risk assessment of F-pollution and pathways of F through organisms and ecosystems, detailed knowledge of F-accumulation in soil fauna, and in earthworms in particular is required.

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

1991-10-01

209

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

210

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

1985-11-01

211

Fundamentals of freeze-drying.  

Science.gov (United States)

Given the increasing importance of reducing development time for new pharmaceutical products, formulation and process development scientists must continually look for ways to "work smarter, not harder." Within the product development arena, this means reducing the amount of trial and error empiricism in arriving at a formulation and identification of processing conditions which will result in a quality final dosage form. Characterization of the freezing behavior of the intended formulation is necessary for developing processing conditions which will result in the shortest drying time while maintaining all critical quality attributes of the freeze-dried product. Analysis of frozen systems was discussed in detail, particularly with respect to the glass transition as the physical event underlying collapse during freeze-drying, eutectic mixture formation, and crystallization events upon warming of frozen systems. Experiments to determine how freezing and freeze-drying behavior is affected by changes in the composition of the formulation are often useful in establishing the "robustness" of a formulation. It is not uncommon for seemingly subtle changes in composition of the formulation, such as a change in formulation pH, buffer salt, drug concentration, or an additional excipient, to result in striking differences in freezing and freeze-drying behavior. With regard to selecting a formulation, it is wise to keep the formulation as simple as possible. If a buffer is needed, a minimum concentration should be used. The same principle applies to added salts: If used at all, the concentration should be kept to a minimum. For many proteins a combination of an amorphous excipient, such as a disaccharide, and a crystallizing excipient, such as glycine, will result in a suitable combination of chemical stability and physical stability of the freeze-dried solid. Concepts of heat and mass transfer are valuable in rational design of processing conditions. Heat transfer by conduction--the dominant mechanism of heat transfer in freeze-drying--is inefficient at the pressures used in freeze-drying. Steps should be taken to improve the thermal contact between the product and the shelf of the freeze dryer, such as eliminating metal trays from the drying process. Quantitation of the heat transfer coefficient for the geometry used is a useful way of assessing the impact of changes in the system such as elimination of product trays and changes in the vial. Because heat transfer by conduction through the vapor increases with increasing pressure, the commonly held point of view that "the lower the pressure, the better" is not true with respect to process efficiency. The optimum pressure for a given product is a function of the temperature at which freeze-drying is carried out, and lower pressures are needed at low product temperatures. The controlling resistance to mass transfer is almost always the resistance of the partially dried solids above the submination interface. This resistance can be minimized by avoiding fill volumes of more than about half the volume of the container. The development scientist should also recognize that very high concentrations of solute may not be appropriate for optimum freeze-drying, particularly if the resistance of the dried product layer increases sharply with concentration. Although the last 10 years has seen the publication of a significant body of literature of great value in allowing development scientists and engineers to "work smarter," there is still much work needed in both the science and the technology of freeze-drying. Scientific development is needed for improving analytical methodology for characterization of frozen systems and freeze-dried solids. A better understanding of the relationship between molecular mobility and reactivity is needed to allow accurate prediction of product stability at the intended storage temperature based on accelerated stability at higher temperatures. This requires that the temperature dependence of glass transition-associated mobili

Nail, Steven L; Jiang, Shan; Chongprasert, Suchart; Knopp, Shawn A

2002-01-01

212

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

Science.gov (United States)

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

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

2013-01-01

213

Freezing mechanisms in concrete  

International Nuclear Information System (INIS)

This study addresses the durability of concrete subjected to freezing conditions. The solidification of pore water solution generates different local pressures in the cement matrix. It is possible to distinguish between 'Hydraulic Pressures', 'Osmotic Pressures' and pressures resulting from undercooled fluid circulations according to Litvan's Theory. By overcoming the local tensile strength of the material, these pressures can cause the material to crack. In the pores, ice does not form at 0 deg C but at lower temperatures, as low as -40 deg C. In the literature, this mechanism is explained by the superimposition of different effects, i.e. size restrictions and the presence of solutes. An attempt was made to evaluate numerically the undercooling of pore water solution due to these effects, using the thermodynamic equilibrium between phases for this calculation. An experimental study was carried out using a year old saturated Ordinary Cement Paste with a water to cement mass ratio of 0.5. The cement paste was cured for three months in NaOH and KOH solutions at 3 and 10 g/l, respectively, and then stored in a plastic bag to prevent water release. Solute concentrations were selected from values given by Longuet, who made pore water solution chemistry analyses. The ice formation temperature was measured by Differential Scanning Calorimetry on the BT 2.15 Setaram Calorimeter, and the values are shown. Two different peaks were observed for ice formation, centered near -10 deg C and -40 deg C respectively. According to the classic porous description of the material with capillary and gel pores, peak 1 would correspond to ice formation in capillary pores, and peak 2 in the coarser hydrate pores. Almost all the ice melted near -5 deg C. Undercooling of pore water solution was evaluated using thermodynamic laws. Based on the work done by Radjy, complete equilibrium between phases is described by Equation 1. The effects evaluated were: (i) size restrictions, (ii) presence of solutes, and (iii) confinement pressure of solution in the pores. All these effects tend to lower the freezing point of the solution. Integrated equations corresponding to each of the effects and results shown as graphs are presented respectively in Equations 2, 3 and 4 and Figures 2, 3 and 4. In order to evaluate undercooling of pore water solution, a medium capillary pore and a medium hydrate pore were modeled with the characteristics given in Table 1, and the associated undercooling then calculated, as -2.8 and -6.4 deg C respectively. The calculated undercooling were significantly lower than experimentally observed undercooling. In fact, calculated undercooling correspond to the lowering of the pore water solution freezing points as well the stability temperatures of ice crystals in the medium pores. This explains why the calculated values show good agreement with measured ice melt temperatures. One possible explanation of the lowest ice formation temperatures observed can be found in the mechanisms of ice germination. These mechanisms are described by nucleation theory [8]. Ice forms from clusters or nuclei which are heaps of H_2O molecules tied by hydrogen bonds. At any given temperature below 0 deg C, a nucleus must reach a critical size before nucleation can occur, followed by ice crystal growth. At the stability temperature, the concentration in a critical nucleus is very low, and the probability of nucleation is 0. With decreasing temperature, the critical nucleus concentration, increases exponentially up to a threshold value, where nucleation probability suddenly becomes 1 and ice forms. In a volume of pure H_2O molecules, the spontaneous nucleation point is close to -40 deg C, as in the case of ice formation in clouds. For a volume of ordinary water, impurities and surfaces act as nucleation sites. They modify the surface energy of the clusters and permit nucleation at a temperature closer to the crystal stability temperature, which is generally 0 deg C. Considering all these factors, it appears possible to study the ice formation temperature in a c

2000-01-01

214

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

Science.gov (United States)

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

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

1987-01-01

215

Elemental and mineralogical changes in soils due to bioturbation along an earthworm invasion chronosequence in Northern Minnesota  

International Nuclear Information System (INIS)

Minnesota forested soils have evolved without the presence of earthworms since the last glacial retreat. When exotic earthworms arrive, enhanced soil bioturbation often results in dramatic morphological and chemical changes in soils with negative implications for the forests' sustainability. However, the impacts of earthworm invasion on geochemical processes in soils are not well understood. This study attempts to quantify the role of earthworm invasion in mineral chemical weathering and nutrient dynamics along an earthworm invasion chronosequence in a sugar maple forest in Northern Minnesota. Depth and rates of soil mixing can be tracked with atmospherically derived short lived radioisotopes 210Pb and 137Cs. Their radioactivities increase in the lower A horizon at the expense of the peak activities near the soil surface, which indicate that soil mixing rate and its depth reach have been enhanced by earthworms. Enhanced soil mixing by earthworms is consistent with the ways that the vertical profiles of elemental and mineralogical compositions were affected by earthworm invasion. Biologically cycled Ca and P have peak concentrations near the soil surface prior to earthworm invasion. However, these peak abundances significantly declined in the earthworm invaded soils presumably due to enhanced soil mixing. It is clear that enhanced soil mixing due to earthworms also profoundly altered the vertical distribution of most mineral species within A horizons. Though the mechanisms are not clear yet, earthworm invasion appears to have contributed to net losses of clay mineral species and opal from the A horizons. As much as earthworms vertically relocated minerals and elements, they also intensify the contacts between organic matter and cations as shown in the increased amount of Ca and Fe in organically complexed and in exchangeable pools. With future studies on soil mixing rates and elemental leaching, this study will quantitatively and mechanically address the role of earthworms in geochemical evolution of soils and forests' nutrient dynamics.

2011-06-01

216

Elemental and mineralogical changes in soils due to bioturbation along an earthworm invasion chronosequence in Northern Minnesota  

Energy Technology Data Exchange (ETDEWEB)

Minnesota forested soils have evolved without the presence of earthworms since the last glacial retreat. When exotic earthworms arrive, enhanced soil bioturbation often results in dramatic morphological and chemical changes in soils with negative implications for the forests' sustainability. However, the impacts of earthworm invasion on geochemical processes in soils are not well understood. This study attempts to quantify the role of earthworm invasion in mineral chemical weathering and nutrient dynamics along an earthworm invasion chronosequence in a sugar maple forest in Northern Minnesota. Depth and rates of soil mixing can be tracked with atmospherically derived short lived radioisotopes {sup 210}Pb and {sup 137}Cs. Their radioactivities increase in the lower A horizon at the expense of the peak activities near the soil surface, which indicate that soil mixing rate and its depth reach have been enhanced by earthworms. Enhanced soil mixing by earthworms is consistent with the ways that the vertical profiles of elemental and mineralogical compositions were affected by earthworm invasion. Biologically cycled Ca and P have peak concentrations near the soil surface prior to earthworm invasion. However, these peak abundances significantly declined in the earthworm invaded soils presumably due to enhanced soil mixing. It is clear that enhanced soil mixing due to earthworms also profoundly altered the vertical distribution of most mineral species within A horizons. Though the mechanisms are not clear yet, earthworm invasion appears to have contributed to net losses of clay mineral species and opal from the A horizons. As much as earthworms vertically relocated minerals and elements, they also intensify the contacts between organic matter and cations as shown in the increased amount of Ca and Fe in organically complexed and in exchangeable pools. With future studies on soil mixing rates and elemental leaching, this study will quantitatively and mechanically address the role of earthworms in geochemical evolution of soils and forests' nutrient dynamics.

Resner, Kathryn [Dept. of Soil, Water, and Climate, University of Minnesota, 439 Borlaug Hall, 1991 Upper Buford Circle, St. Paul, MN, 55108-6028 (United States); Yoo, Kyungsoo, E-mail: kyoo@umn.edu [Dept. of Soil, Water, and Climate, University of Minnesota, 439 Borlaug Hall, 1991 Upper Buford Circle, St. Paul, MN, 55108-6028 (United States); Hale, Cindy [University of Minnesota Duluth, The Natural Resources Research Institute, 5013 Miller Trunk Hwy. Duluth, MN 55811 (United States); Aufdenkampe, Anthony [Assistant Research Scientist - Isotope and Organic Geochemistry, Stroud Water Research Center, 970 Spencer Road, Avondale, PA 19311 (United States); Blum, Alex [US Geological Survey, 3215 Marine St., Boulder, CO 80303 (United States); Sebestyen, Stephen [Research Hydrologist, USDA Forest Service, Northern Research Station, Grand Rapids, MN 55744-3399 (United States)

2011-06-15

217

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

Science.gov (United States)

Sorption of organic matter on mineral surface is critical for protection of organic carbon (C) against decomposition and thus may potentially increase the capacity of soils to store C. Such sorption, however, requires physical contacts between organic matter and available mineral surfaces. This study attempts to better understand how bioturbation by invasive earthworms influences the contacts between organic matter and mineral surface, and affects sorption of organic matter on mineral surface. Vertical soil mixing is a direct consequence of the introduction of invasive earthworms in natural forests previously devoid of native earthworm populations. Here we focus on an intensively studied earthworm invasion chronosequence in a glaciated sugar maple forest in northern Minnesota. With the advance of invasive earthworms, leaf litter disappears while the A horizon expands at the expense of the overlying litter layer and the underlying wind blown silt materials. Earthworms' biomasses and functional group compositions, depth profiles of soil C contents, and total and organic matter-covered mineral surface areas are determined at different stages of invasion. We found that minerals' specific surface areas (SSA) in the A horizons decrease with greater degree of earthworm invasion. Furthermore, less fractions of mineral SSA were found to be coated with organic C in the soils with active earthworm populations. These observations appear to contradict another finding that amounts of crystalline Fe oxide and organically-complexed Fe increase with the greater earthworm population. The overall trend shows that earthworms' active mixing resulting in incorporating silt materials with low SSA from the underlying E horizons to the A horizons. We are currently investigating whether the increased crystalline Fe oxides and organically-complexed Fe pools with increasing earthworm population helped reducing the gradient of overall trend. Our study highlights the importance of earthworm bioturbation and material processing through earthworm intestines in determining the interactions between organic matter and mineral surface and thus helps understanding how soils' capacity to stabilize organic matter is influenced by invasive earthworm species.

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

2012-12-01

218

Mode of action of the COR15a gene on the freezing tolerance of Arabidopsis thaliana  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Constitutive expression of the cold-regulated COR15a gene of Arabidopsis thaliana results in a significant increase in the survival of isolated protoplasts frozen over the range of ?4.5 to ?7°C. The increased freezing tolerance is the result of a decreased incidence of freeze-induced lamellar-to-hexagonal II phase transitions that occur in regions where the plasma membrane is brought into close apposition with the chloroplast envelope as a result of freeze-induced dehydration. Moreover, ...

1998-01-01

219

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

Science.gov (United States)

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

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

2006-01-01

220

The Impact of Invasive Earthworm Activity on Biopolymer Character of ýDecayed Litter ý  

Science.gov (United States)

Over the last 400-500 years invasive European earthworm populations have ýmoved steadily into North American forests either previously devoid of ýearthworms or that contained their own native populations. This has profound ýimpacts upon litter decay and soil organic matter dynamics. To determine the ýimpact of earthworm activity on the biopolymer and stable isotope chemistry of ýlitter residues and the nature of organic carbon moved to the soil profile we ýanalyzed tulip poplar leaves from a multi-year addition experiment in open ýsurface decay litter and litter bag decay experiments, as well as the associated ýsoils among forest plots that varied in non-native earthworm density and ýbiomass. The chemical alteration of biopolymers was tracked with FTIR ýspectroscopy, 13C-TMAH thermochemolysis, alkaline CuO extraction, and stable ýisotope mass spectrometry. Earthworm activity resulted in residues and soil ýparticulate organic matter depleted in cuticular aliphatic components and ýpolyphenols but highly enriched in ether-linked lignin with respect to initial litter ýmaterial. Decay in low earthworm abundance plots, as well as all experiments ýwith earthworm-excluding litter bags, resulted in enrichment in cutin aliphatics ýand only minor increases in ether linked lignin phenols which was also reflected ýin the soils below the amendments. Additionally, the stable carbon and nitrogen ýisotope composition of tulip poplar residues became isotopically distinct. The ýresults from litter bag decays were only reflective of the chemistry at sites with ývery low earthworm abundances. ý

Filley, T.; Crow, S.; Johnston, C.; McCormick, M.; Szlavecz, K.

2007-12-01

 
 
 
 
221

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.

2010-01-01

222

A review of studies performed to assess metal uptake by earthworms  

Energy Technology Data Exchange (ETDEWEB)

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.

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

223

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

224

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.

2011-07-01

225

Freeze Protection in Gas Holders  

DEFF Research Database (Denmark)

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 â??tank waterâ? 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 suï¬?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.

Hjorth, Poul G.

2008-01-01

226

Freezing singularities in water drops  

CERN Document Server

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.

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

2011-01-01

227

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

Energy Technology Data Exchange (ETDEWEB)

Coelomocytes of the earthworm Lumbricus terrestris caused significant spontaneous allogeneic cytotoxicity in a 24-h trypan blue assay, but not in an assay using lactate dehydrogenase (LDH) release. Allogeneic cytotoxicity assays using cells from worms exposed to polychlorinated biphenyls (PCBs) suggest that PCBs can suppress a natural killing (NK-like) reaction. The implications of this work are twofold: understanding the evolution of natural killing (NK-like) activity and providing preliminary information on how spontaneous killing, a component of cellular immunity, may be compromised by pollutants.

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

1995-10-01

228

Bioaccumulation in earthworm exposed to uranium particles and anions  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This study contains information about the bioaccumulation of uranium (U) in earthworms following exposure of the worms exposed to different uranium species in food (horse manure). Three different uranium species were used: synthesized uranium nano-micrometer particles (UO2 and U3O8) and uranyl ions at two different concentrations (50 and 500 ?g/g dw manure). The study started with the culturing of worms, growing them in OECD soil and ended by performing uranium measurements by ICP-MS of four...

Basnet, Pabitra

2012-01-01

229

Concentration of cadmium in Coturnix quail fed earthworms  

Energy Technology Data Exchange (ETDEWEB)

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

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

1986-01-01

230

La fecundidad de las lombrices rojas – (Fecundity of red earthworms  

Directory of Open Access Journals (Sweden)

Full Text Available ResumenDesde fines de la década del 80 se ha ampliado sustancialmente elconocimiento acerca de la biología reproductiva de Eisenia fetida y Eisenia andrei, permitiendo optimizar las estrategias de conducción de los lombricultivos. La fecundidad es uno de los parámetros reprobiológicos que más allá de las fluctuaciones esperadas (0-9 lombrices / cocón ha generado discusión.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.

Schuldt, Miguel

2010-10-01

231

Wood frog adaptations to overwintering in Alaska: new limits to freezing tolerance.  

Science.gov (United States)

We investigated the ecological physiology and behavior of free-living wood frogs [Lithobates (Rana) sylvaticus] overwintering in Interior Alaska by tracking animals into natural hibernacula, recording microclimate, and determining frog survival in spring. We measured cryoprotectant (glucose) concentrations and identified the presence of antifreeze glycolipids in tissues from subsamples of naturally freezing frogs. We also recorded the behavior of wood frogs preparing to freeze in artificial hibernacula, and tissue glucose concentrations in captive wood frogs frozen in the laboratory to -2.5°C. Wood frogs in natural hibernacula remained frozen for 193±11 consecutive days and experienced average (October-May) temperatures of -6.3°C and average minimum temperatures of -14.6±2.8°C (range -8.9 to -18.1°C) with 100% survival (N=18). Mean glucose concentrations were 13-fold higher in muscle, 10-fold higher in heart and 3.3-fold higher in liver in naturally freezing compared with laboratory frozen frogs. Antifreeze glycolipid was present in extracts from muscle and internal organs, but not skin, of frozen frogs. Wood frogs in Interior Alaska survive freezing to extreme limits and durations compared with those described in animals collected in southern Canada or the Midwestern United States. We hypothesize that this enhancement of freeze tolerance in Alaskan wood frogs is due to higher cryoprotectant levels that are produced by repeated freezing and thawing cycles experienced under natural conditions during early autumn. PMID:24737762

Larson, Don J; Middle, Luke; Vu, Henry; Zhang, Wenhui; Serianni, Anthony S; Duman, John; Barnes, Brian M

2014-06-15

232

Antagonism Between Chlorpyrifos and Flaxedil in Toad and Earthworm Neuromuscular Transmission  

Directory of Open Access Journals (Sweden)

Full Text Available The cholinesterase inhibition effect of chlorpyrifos, a commercial insecticide, was tested by its antagonism to the acetylcholine inhibition effect of flaxedil in 30 isolated nerve-sartorius muscle preparations of the toad, compared with its antagonism in 30 isolated nerve cord-body wall muscle preparations of the earthworm. Inhibition and facilitation in this antagonism were measured by changes in depolarizing rate of toad endplate potential and in earthworm slow potential and by changes in interstimulus interval for evoking an action potential in toad preparations and a graded spike potential in earthworm preparations. Earthworm depolarizing rate (0.32 V s-1 in its normal Ringer was five times lower than that (1.50 V s-1 of toad under [Flaxedilï]o = 3 x 10-3 g cc-1. Earthworm interstimulus interval (15.6 ms in its normal Ringer was nine times longer than that (1.75 ms of toad under [Flaxedil]o = 3 x 10-3 g cc-1. [Flaxedilï]o between 3 x 10-4 g cc-1 and 5 x 10-4 g cc-1 attenuated 25% of toad depolarizing rate and 23% of earthworm depolarizing rate, 60% of toad interstimulus interval and eliminated the earthworm interstimulus interval almost entirely. Enhancement of toad depolarizing rate and interstimulus interval by chlorpyrifos between 5 x 10-4 g cc-1 and 10-2 g cc-1 after being attenuated by flaxedil was not significant but was significant in the earthworm preparation. Inhibition of earthworm cholinesterase by chlorpyrifos may be related to its lower neuromuscular excitability than that of the toad.

Yong-Chiang Chang

2006-01-01

233

Geochemistry and Chemical Weathering in Soils along an Earthworm Invasion Gradient  

Science.gov (United States)

One of the central tenets in geomorphology is that a chemical denudation rate is limited by the total denudation rate, which controls how fast minerals are exposed to reactive environments of the earth’s surface. Though the mineral supply rate has been routinely tied to tectonic uplifts, in soil mantled landscapes, organisms such as earthworms may also significantly contribute to exposing minerals to varying geochemical environments and thus altering chemical denudation rates of the landscapes they inhabit through mineral translocation. In glaciated parts of North America, many forests evolved without native earthworms, since the last glacial retreat, until they were invaded by exotic earthworm species that arrived with agriculture, recreational fishing, and logging. Therefore, an earthworm invasion chronosequence in northern Minnesota--the focus of this ongoing study--provides an ideal natural laboratory to quantitatively study how burrowing organisms, by mixing soils, contribute to chemically denuding the landscapes. We are currently determining the inorganic chemistry of soils along a ~200 meter long transect that includes pre earthworm invasion soils as well as soils populated with several earthworm species with different burrowing habits. Additionally, six soils pits along the transect are densely installed with lysimeters, piezometers, and gas sampling tubes. The soils’ elemental chemistry profiles show that earthworms have significantly relocated minerals vertically, which is consistent with the 210Pb activity profiles determined with gamma spectroscopy. Major elements, depending on their solubility, biological demands, and susceptibility to be complexed with organic matter, respond to the enhanced mixing rates in different ways. To constrain the impacts of earthworm burrowing on chemical denudation, we are also measuring cations, anions, and alkalinity in the water samples collected with the lysimeters and piezometers. Ultimately, the soil and water chemistry and 210Pb activities, together with ongoing monitoring of earthworms’ species composition and population density, will allow us to understand how and to what degree the soil mixing organisms affect chemical denudation of landscapes, which is central to our efforts in finding the topographic signatures of life.

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

2010-12-01

234

Freezing of simple liquid metals  

CERN Multimedia

Freezing of simple liquid metals and the relative stabilities of competing crystalline solids are investigated using thermodynamic perturbation theory, the interactions between ions being modeled by effective pair potentials derived from pseudopotential theory. The ionic free energy of the solid phase is calculated, to first order in the perturbation potential, using classical density-functional theory and an accurate approximation to the hard-sphere radial distribution function. Free energy calculations for Na, Mg, and Al yield well-defined freezing transitions and structural free energy differences for bcc, fcc, and hcp crystals in qualitative agreement with experiment.

Denton, A R; Hafner, J H

1999-01-01

235

A two-dimensional electrophoresis reference map of the earthworm Eisenia fetida  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The molecular mechanisms underlying innate immunity in the earthworm E. fetida remain unclear. For the recognition of innate immunity in the earthworm E. fetida, a detailed knowledge of this proteome is a prerequisite. The absence of a high-resolution E. fetida proteome map prompted us to determine E. fetida protein spots that can be visualised on 2-D protein gels. In this study, we present a preliminary description of the whole earthworm E. fetida proteo...

Xing Wang; Yi Zhang; Zhenjun Sun

2012-01-01

236

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

Science.gov (United States)

We are investigating the impact of exotic earthworms on the rate of nutrient and ion release from soil chemical weathering along an ~200 m invasion chronosequence in a northern Minnesota sugar maple forest. The earthworms belong to three ecological groups that represent different feeding and burrowing behaviors, all of which were introduced from Europe to the previously earthworm-free Great Lakes Region through fishing and agricultural activities. As earthworms digest and mix the soil, we hypothesize that they significantly alter chemical weathering processes by incorporating mineral surfaces to new geochemical environments in their intestines and at different soil depths. The effect of mixing on soil morphology is dramatic, but biogeochemical changes remain largely unknown and therefore are poorly coupled to the current and potential changes in forest ecosystems under the threat of exotic earthworms. We analyze the activities of short-lived isotopes 137-Cs and 210-Pb along with the inorganic chemistry of soil, water, and leaf litter across an invasion transect and link these measurements to the biomass and species composition of exotic earthworms. Earthworms vertically relocate minerals and organic matter largely within the top ~10 cm, which is reflected in the depth profiles of the short-lived isotopes. Among the inorganic nutrients analyzed, Ca is of particular interest due to sugar maple's aptitude for recycling Ca. Fractional mass loss values (tau) of Ca, relative to the soil's parent material, show an enrichment factor of 14 in the least invaded A horizon soils. However, such a high enrichment factor declines dramatically in the heavily invaded soils, suggesting that earthworm activities contribute to leaching Ca. In contrast, the enrichment factor of Fe increases with greater degrees of earthworm invasion, which is consistent with the extraction chemistry data showing greater quantities of pedogenic crystalline iron oxides and greater mineral specific surface area (presumably due to the crystalline iron oxides) in the heavily invaded soils. Water chemistry of lysimeter samples show a similar trend: the heavily invaded soils show a lower solute concentration of Ca but higher concentrations of Fe. These data indicate that exotic earthworms, while significantly affecting chemical weathering processes in the soils, are seriously altering (1) the budgets of inorganic nutrient in these hardwood forests and (2) the minerals' potential capacity to complex carbon on their surface area. Our ongoing work includes the use of optically stimulated luminescence (OSL) dating which may complement the 137-Cs and 210-Pb data in constraining soil mixing. Additionally, we will incorporate leaf litter chemistry and continue water and earthworm sampling to understand the degree that exotic earthworms contribute to chemical weathering in the Great Lakes hardwood ecosystems.

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

2011-12-01

237

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

Energy Technology Data Exchange (ETDEWEB)

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

Dean-Ross, D.

1983-03-01

238

Spectra of colony size of CHO-fibroblastoma irradiated with 60Co gamma rays after freeze and thaw cycles  

International Nuclear Information System (INIS)

The production of reproductive lethal cell lesions by freeze and thaw cycles has been studied by means of colony size spectrometry in tetraploid CHO-fibroblastoma protected with glycerine. The verification sensitivity of this method is compared with that of the colony formation test, the survival curve of cells and the relative multiplicity. 20 days after a freeze and thaw cycle only the spectrometry of the colony size and the survival curve of the cells and colonies suggest a cell lesion. After 44 days, changes as a consequence of reproductive lethal lesions can be detected only in the spectrum of the colony size. Survival curves of the colonies, survival curves of the cells and relative multiplicities determined on cell strains 44 days after a freeze and thaw cycle are not significatively different from the results of non-frozen control cells. The relation of the average cellular multiplicity after a freeze and thaw cycle to that of the nonfrozen control cells approaches the value of 1 with increased cultivation period after a freeze and thaw cycle. The reproductive lethal lesion after a freeze and thaw cycle is also decreasing with an increased cultivation period. Proliferation lesions by means of 60Co gamma irradiation have been influenced in dependence of the dose by 20 days of freeze and thaw lesions of a cell population. (orig.)

1975-05-01

239

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

Energy Technology Data Exchange (ETDEWEB)

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{sup -3} - 24x10{sup -3} ml/cm{sup 2} 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{sup -3}, 23x10{sup -3}, 24x10{sup -3} and 16x10{sup -3} ml/cm{sup 2} 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.

Khodabandeh, M; Koohi, M K; Shahroziyan, E; Badri, B; Pourfallah, A; Shams, Gh; Sadeghi-Hashjin, G [Faculty of Veterinary Medicine, University of Tehran, Tehran (Iran, Islamic Republic of); Roshani, A [Industrial and Environmental Protection Division, Research Institute of Petroleum Industry (RRIPI), Tehran (Iran, Islamic Republic of); Hobbenaghi, R, E-mail: gsadeghi@ut.ac.ir [Faculty of Veterinary Medicine, Urmia University, Urmia (Iran, Islamic Republic of)

2011-07-06

240

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.

2011-07-06

 
 
 
 
241

Growth and reproduction of earthworms in ultramafic soils.  

Science.gov (United States)

Ultramafic soils are characterized by high concentrations of heavy metals of natural origin-such as chromium, cobalt, manganese, and nickel-as well as a shortage of primary nutrients. This can result in extremely disadvantageous living conditions for all soil-dwelling organisms. Responses to these conditions were addressed by studying growth, cocoon production, and fecundity of earthworms as endpoints of sublethal effects and how this influences the reproductive system and, consequently, population development. Mature specimens of two ecophysiologically different species of earthworms, Eisenia fetida (Savigny) and Aporrectodea caliginosa (Savigny), were exposed for 56 days to an uncontaminated soil and ultramafic soils collected from six ultramafic sites in the Barberton greenstone belt. In all ultramafic soil samples, the specimens of both species grew slower than those in the control soil. In A. caliginosa, an autotomization of the tail section was observed at higher concentrations of heavy metals. At high levels of heavy metals such as manganese, chromium, nickel, and cobalt, a significantly lower cocoon production was recorded for E. fetida, and at medium levels, a time delay in cocoon production was found. A. caliginosa showed an increase in production at medium levels and a decrease at high levels of heavy metals. In both species, no correlation between growth and cocoon viability was found, indicating different target levels for toxicants present in ultramafic soils. To determine effects of these soils on population dynamics, hatching success may be a more useful endpoint of reproduction. PMID:17354041

Maleri, R; Reinecke, S A; Mesjasz-Przybylowicz, J; Reinecke, A J

2007-04-01

242

Biosynthesis of luminescent quantum dots in an earthworm  

Science.gov (United States)

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.

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

2013-01-01

243

Biosynthesis of luminescent quantum dots in an earthworm.  

Science.gov (United States)

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 (Co(3)O(4)) 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 CdCl(2) and Na(2)TeO(3) 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. PMID:23263722

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

2013-01-01

244

Earthworm coelomocytes as nanoscavenger of ZnO NPs  

Science.gov (United States)

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.

2014-01-01

245

Freeze out in hydrodynamical models  

CERN Document Server

We study the problem of negative contributions to final momentum distribution during the freeze out through 3-dimensional hypersurfaces with space-like normal. We suggest a solution for this problem based on the mechanism of continuous emission of particles. We show how the final particle spectrum is obtained in a simple one-dimensional model.

Anderlik, C; Grassi, Frédérique; Hama, Y; Kodama, T; Lázár, Z I; Lazar, Zs.I.

1999-01-01

246

Freezing Tolerance in Mytilus Edulis.  

Science.gov (United States)

Mytilus edulis tolerates freezing to a tissue temperature of -10 deg C, while Venus mercenaria tolerates only -6 deg C. In both species, tissues are injured when 64 per cent of cellular water has been moved to form ice. In Mytilus, 20 percent of cell wate...

R. J. Williams

1969-01-01

247

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

1995-01-01

248

Inheritance of freezing resistance in tuber-bearing Solanum species: evidence for independent genetic control of nonacclimated freezing tolerance and cold acclimation capacity.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Frost or winter survival is regarded as a complex trait with polygenic inheritance. Two major components of this survival in crop plants are freezing tolerance in the nonacclimated state and cold acclimation capacity. To date researchers have not distinguished the two components as separate heritable traits. The mode of inheritance of these two traits was investigated in F1 and backcross populations of two wild diploid potato species (Solanum commersonii and Solanum cardiophyllum) exhibiting ...

1993-01-01

249

Antioxidant defense system responses and DNA damage of earthworms exposed to perfluorooctane sulfonate (PFOS).  

Science.gov (United States)

The use of earthworms as a sublethal endpoint has significantly contributed to the ecological risk assessment of contaminated soils. Few studies have focused on the potential toxicity of PFOS to earthworms in the soil. In this work, artificial soils were tested, and contact filter paper studies were used. The results showed that earthworm growth was generally inhibited. The antioxidant activities of the enzymes superoxide dismutase, peroxidase, catalase and glutathione peroxidase were initially activated and then inhibited. Reduced glutathione content was observed, and malondialdehyde content was elevated over the duration of the exposure. These results suggested that PFOS induced oxidative stress in earthworms. In addition, the values of olive tail moment, tail DNA% and tail length using SCGE showed similar frequency distributions and increased with increases in the PFOS concentration. These results suggest that all concentrations of PFOS cause DNA damage. PMID:23257261

Xu, Dongmei; Li, Chandan; Wen, Yuezhong; Liu, Weiping

2013-03-01

250

Earthworm Abundance and Species Composition in Abandoned Tropical Croplands: Comparisons of Tree Plantations and Secondary Forests.  

Science.gov (United States)

We compared patterns of earthworm abundance and species composition in tree plantations and secondary forests of Puerto Rico. Tree plantations included pine (Pinus carbibaea Morelet) and mahogany (Swietenia macrophylla King) established in the 1930s; 1960...

G. Gonzalez X. Zou S. Borges

1996-01-01

251

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

Science.gov (United States)

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

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

2013-12-01

252

Earthworm activity in a simulated landfill cover soil shifts the community composition of active methanotrophs.  

Science.gov (United States)

Landfills represent a major source of methane in the atmosphere. In a previous study, we demonstrated that earthworm activity in landfill cover soil can increase soil methane oxidation capacity. In this study, a simulated landfill cover soil mesocosm (1 m × 0.15 m) was used to observe the influence of earthworms (Eisenia veneta) on the active methanotroph community composition, by analyzing the expression of the pmoA gene, which is responsible for methane oxidation. mRNA-based pmoA microarray analysis revealed that earthworm activity in landfill cover soil stimulated activity of type I methanotrophs (Methylobacter, Methylomonas, Methylosarcina spp.) compared to type II methanotrophs (particularly Methylocystis spp.). These results, along with previous studies of methanotrophs in landfill cover soil, can now be used to plan in situ field studies to integrate earthworm-induced methanotrophy with other landfill management practises in order to maximize soil methane oxidation and reduce methane emissions from landfills. PMID:21925596

Kumaresan, Deepak; Héry, Marina; Bodrossy, Levente; Singer, Andrew C; Stralis-Pavese, Nancy; Thompson, Ian P; Murrell, J Colin

2011-12-01

253

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

Science.gov (United States)

Carbon storage was measured in seven types of forest (alder, oak, lime, willow-birch, pine, spruce and larch) about 30 years old developed in on e large post mining site as split plot design. The carbon storage in soil wary substantial and represent 10-100% of carbon storage in aboveground wood biomass. Carbon storage in soil do not show any correlation with litter input but correlate significantly and positively with earthworm abundance, and micromorphological traces of earthworm activity. Field and laboratory microcosm experiment showed that earthworm mediated soil mixing support carbon storage in soil. Detailed study of soil aggregates created by worms and other forces indicated that worm aggregates contain much larger content of POC. This indicate that soil bioturbation by earthworms may significantly increase carbon storage in soil.

Frouz, J.; Pizl, V.

2009-04-01

254

Heavy metal uptake from municipal waste compost by the earthworm Eisenia foetida (Savigny 1826)  

Energy Technology Data Exchange (ETDEWEB)

The uptake of heavy metals and toxic elements by the adult earthworms Eisenia foetida kept in municipal waste compost for 55 and 104 days and by the juveniles was investigated. The uptake of Cu, Zn and Ni increased to constant levels, which appear to be regulated by the physiology of the earthworms. In contrary to this Cd, Hg and As continued to accumulate in the tissues of the earthworms throughout the exposure time. The Pb concentration ratio increased also, but was low (< 0.05). The living conditions for the earthworms in municipal waste compost were satisfactory but the results demonstrate that their use for biological conversion of waste compost to biomass for further animal nutrition is limited by the accumulation of cadmium and mercury.

Fleckenstein, J.; Graff, O.

1982-01-01

255

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

Science.gov (United States)

Herbicides containing glyphosate are widely used in agriculture and private gardens, however, surprisingly little is known on potential side effects on non-target soil organisms. In a greenhouse experiment with white clover we investigated, to what extent a globally-used glyphosate herbicide affects interactions between essential soil organisms such as earthworms and arbuscular mycorrhizal fungi (AMF). We found that herbicides significantly decreased root mycorrhization, soil AMF spore biomass, vesicles and propagules. Herbicide application and earthworms increased soil hyphal biomass and tended to reduce soil water infiltration after a simulated heavy rainfall. Herbicide application in interaction with AMF led to slightly heavier but less active earthworms. Leaching of glyphosate after a simulated rainfall was substantial and altered by earthworms and AMF. These sizeable changes provide impetus for more general attention to side-effects of glyphosate-based herbicides on key soil organisms and their associated ecosystem services. PMID:25005713

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

2014-01-01

256

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

Directory of Open Access Journals (Sweden)

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.

T. Chuasavathi

2001-01-01

257

Identification of Earthworms species in Sari Township in Northern Iran, 2007-2008  

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The aim of this study is identification of earthworm species gathered from the geographic regions of Sari Township. Samples gathered from different regions of Sari Township fixed by formaldehyde and alcohol solution in several stages and placed into formalin tubes (5%), in addition to providing sample characteristics tabled by Graff identification key, fixed earthworms are recognized. After recognition, analysis obtained data from geographical information of sampling regions and from original...

Yousefi, Z.; Ramezani, M.; Kh Akbari Mohamadi, S.; Mohammadpour, R. A.; Nemati, A.

2009-01-01

258

Identification and Optimization of Classifier Genes from Multi-Class Earthworm Microarray Dataset  

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Monitoring, assessment and prediction of environmental risks that chemicals pose demand rapid and accurate diagnostic assays. A variety of toxicological effects have been associated with explosive compounds TNT and RDX. One important goal of microarray experiments is to discover novel biomarkers for toxicity evaluation. We have developed an earthworm microarray containing 15,208 unique oligo probes and have used it to profile gene expression in 248 earthworms exposed to TNT, RDX or neither. W...

2010-01-01

259

Visual Reconstruction and Feature Analysis of the Three-Dimensional Surface of Earthworm  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper demonstrates a method for visual reconstruction and feature analysis of the three-dimensional surface of earthworm in CATIA (Computer Aided Three Dimensional Interactive Application) and IDL (Interactive Data Language). The earthworm, with a relatively simple surface morphology and good capability in reducing soil adhesion and resistance, was selected to study the feasible methods in the visual reconstruction and feature analysis of the three-dimensional surface of living things. T...

Li, Yin-wu; Zhao, Guang-sheng; Wang, Jing-chun; Sun, Xiu-wen; Peng, Hua-xin; Qin, Fa-xiang

2010-01-01

260

Earthworms and management affect organic matter incorporation and microaggregate formation in agricultural soils  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Through their feeding activities and cast production, earthworms influence both aggregate turnover and soil organic matter (SOM) dynamics. We studied the impact of earthworm activity on soil macro- and microaggregation and SOM incorporation in different farming systems. Dry-sieved aggregates (4¿12.5 mm) of a permanent pasture (PP), a conventional arable field (CA) and an organic arable field (OA) (0¿10 and 10¿20 cm depth) were separated into different aggregate fractions, which were analyz...

Pulleman, M. M.; Six, J.; Uyl, A.; Marinissen, J. C. Y.; Jongmans, A. G.

2005-01-01

 
 
 
 
261

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

We have developed a model system to assess the influence of earthworm activity on the transfer of plasmid pJP4 from an inoculated donor bacterium, Pseudomonas fluorescens C5t (pJP4), to indigenous soil microorganisms. Three different earthworm species (Lumbricus terrestris, Lumbricus rubellus, and Aporrectodea trapezoides), each with unique burrowing, casting, and feeding behaviors, were evaluated. Soil columns were inoculated on the surface with 10(8) cells per g of soil of the donor bacteri...

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

1996-01-01

262

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.

2011-11-01

263

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.

2010-11-01

264

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

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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...

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

2012-01-01

265

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 decompositi...

Yahya Kooch; Hamid Jalilvand

2008-01-01

266

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

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Micro-scale changes in earthworm communities and ground cover types were studied along five transect lines in an unmanaged beech forest (Fontainebleau forest, France). Spatial patterns were interpreted in the light of interactions between earthworm species and forest architecture, ground vegetation and quantity as well as quality of litter. The anecic Lumbricus terrestris was associated with patches of the grass Melica uniflora, with poor litter cover, while most epigeic species were favoured...

Campana, Cyril; Gauvin, Ste?phanie; Ponge, Jean-franc?ois

2002-01-01

267

Earthworm-Mycorrhiza Interactions Can Affect the Diversity, Structure and Functioning of Establishing Model Grassland Communities  

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Both earthworms and arbuscular mycorrhizal fungi (AMF) are important ecosystem engineers co-occurring in temperate grasslands. However, their combined impacts during grassland establishment are poorly understood and have never been studied. We used large mesocosms to study the effects of different functional groups of earthworms (i.e., vertically burrowing anecics vs. horizontally burrowing endogeics) and a mix of four AMF taxa on the establishment, diversity and productivity of plant communi...

Zaller, Johann G.; Heigl, Florian; Grabmaier, Andrea; Lichtenegger, Claudia; Piller, Katja; Allabashi, Roza; Frank, Thomas; Drapela, Thomas

2011-01-01

268

Earthworms: Charles Darwin’s ‘Unheralded Soldiers of Mankind’: Protective & Productive for Man & Environment  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Earthworms promises to provide cheaper solutions to several social, economic and environmental problems plaguing the human society. Earthworms can safely manage all municipal and industrial organic wastes including sewage sludge and divert them from ending up in the landfills. Their body work as a ‘biofilter’ and they can ‘purify’ and also ‘disinfect’ and ‘detoxify’ municipal and several industrial wastewater. They reduce the BOD & COD loads and the TDSS of wastewater signific...

Sinha, Rajiv K.; Krunal Chauhan; Dalsukh Valani; Vinod Chandran; Brijal Kiran Soni; Vishal Patel

2010-01-01

269

Heavy metal accumulation in earthworms exposed to spatially variable soil contamination.  

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Ecotoxicity of contaminated soil is commonly tested in standard laboratory tests. Extrapolation of these data to the field scale is complicated due to considerable differences between conditions in laboratory tests and conditions in situ in contaminated soils. In this thesis, heavy metal accumulation in earthworms was studied under various laboratory conditions to identify and obtain knowledge that is needed to predict accumulation in earthworms exposed to in situ soil contamination. Both Cu...

Marinussen, M. P. J. C.

1997-01-01

270

Survival strategies in arctic ungulates  

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Arctic ungulates usually neither freeze nor starve to death despite the rigours of winter. Physiological adaptations enable them to survive and reproduce despite long periods of intense cold and potential undernutrition. Heat conservation is achieved by excellent insulation combined with nasal heat exchange. Seasonal variation in fasting metabolic rate has been reported in several temperate and sub-arctic species of ungulates and seems to occur in muskoxen. Surprisingly, there is no evidence ...

1990-01-01

271

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Chiarawatchai, Nathasith

2010-01-01

272

Earthworm surface casts affect soil erosion by runoff water and phosphorus transfer in a temperate maize crop  

Digital Repository Infrastructure Vision for European Research (DRIVER)

To test the hypothesis that earthworm surface casts contribute to soil erosion and nutrient transfers in a temperate maize crop, two rainfall experiments were set up. One was focused on the erodibility of earthworm casts, the second examined in how casts affect water runoff and nutrient transfers. Casts produced from anecic and endogeic earthworm species were both analyzed. Visual observations in the field showed no cast transport but only cast disintegration and transfers of particles. Erodi...

Le Bayon, Rene?e-claire; Binet, Franc?oise

2009-01-01

273

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

Science.gov (United States)

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

Fujii, Katsuhiko; Ikeda, Kana; Yoshida, Seo

2012-09-01

274

Earthworms dilong: ancient, inexpensive, noncontroversial models may help clarify approaches to integrated medicine emphasizing neuroimmune systems.  

Science.gov (United States)

Earthworms have provided ancient cultures with food and sources of medicinal cures. Ayurveda, traditional Chinese medicine (TCM), and practices in Japan, Vietnam, and Korea have focused first on earthworms as sources of food. Gradually fostering an approach to potential beneficial healing properties, there are renewed efforts through bioprospecting and evidence-based research to understand by means of rigorous investigations the mechanisms of action whether earthworms are used as food and/or as sources of potential medicinal products. Focusing on earthworms grew by serendipity from an extensive analysis of the earthworm's innate immune system. Their immune systems are replete with leukocytes and humoral products that exert credible health benefits. Their emerging functions with respect to evolution of innate immunity have long been superseded by their well-known ecological role in soil conservation. Earthworms as inexpensive, noncontroversial animal models (without ethical concerns) are not vectors of disease do not harbor parasites that threaten humans nor are they annoying pests. By recognizing their numerous ecological, environmental, and biomedical roles, substantiated by inexpensive and more comprehensive investigations, we will become more aware of their undiscovered beneficial properties. PMID:22888362

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

2012-01-01

275

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

Science.gov (United States)

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

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

2014-07-01

276

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

International Nuclear Information System (INIS)

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.

2011-04-01

277

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

278

Influence of plant-earthworm interactions on SOM chemistry and p,p'-DDE bioaccumulation.  

Science.gov (United States)

Laboratory experiments assessed how bioaccumulation of weathered p,p'-DDE from soil and humic acid (HA) chemistry are affected by interactions between the plants Cucurbita pepo ssp. pepo and ssp. ovifera and the earthworms Eisenia fetida, Lumbricus terrestris, and Apporectodea caliginosa. Total organochlorine phytoextraction by ssp. pepo increased at least 25% in the presence of any of the earthworm species (relative to plants grown in isolation). Uptake of the compound by ssp. ovifera was unaffected by earthworms. Plants influenced earthworm bioaccumulation as well. When combined with pepo, p,p'-DDE levels in E. fetida decreased by 50%, whereas, in the presence of ovifera, bioconcentration by L. terrestris increased by more than 2-fold. Spectral analysis indicated a decrease in hydrophobicity of HA in each of the soils in which both pepo and earthworms were present. However, HA chemistry from ovifera treatments was largely unaffected by earthworms. Risk assessments of contaminated soils should account for species interactions, and SOM chemistry may be a useful indictor of pollutant bioaccumulation. PMID:21421253

Kelsey, Jason W; Slizovskiy, Ilya B; Petriello, Michael C; Butler, Kelly L

2011-05-01

279

Earthworms: Charles Darwin’s ‘Unheralded Soldiers of Mankind’: Protective & Productive for Man & Environment  

Directory of Open Access Journals (Sweden)

Full Text Available Earthworms promises to provide cheaper solutions to several social, economic and environmental problems plaguing the human society. Earthworms can safely manage all municipal and industrial organic wastes including sewage sludge and divert them from ending up in the landfills. Their body work as a ‘biofilter’ and they can ‘purify’ and also ‘disinfect’ and ‘detoxify’ municipal and several industrial wastewater. They reduce the BOD & COD loads and the TDSS of wastewater significantly. They can even remove the EDCs (endocrine disrupting chemicals from sewage which is not removed by the conventional sewage treatments plants. Earthworms can bio-accumulate and bio-transform many chemical contaminants including heavy metals and organic pollutants in soil and clean-up the contaminated lands for re-development. Earthworms restore & improve soil fertility by their secretions (growth hormones and excreta (vermicast with beneficial soil microbes & boost ‘crop productivity’. They have potential to replace the environmentally destructive chemical fertilizers from farm production. The ‘protein rich’ earthworm biomass is being used for production of ‘nutritive feed materials’ for fishery, dairy & poultry industries. They are also being used as ‘raw materials’ for rubber, lubricant and detergent industries. The bioactive compounds isolated from earthworms are finding new uses in production of ‘life saving medicines’ for cardiovascular diseases and cancer cure.

Rajiv K. Sinha

2010-09-01

280

Response of Nitrous Oxide Flux to Addition of Anecic Earthworms to an Agricultural Field  

Directory of Open Access Journals (Sweden)

Full Text Available The burrowing and feeding activities of earthworms may have a strong effect on the flux of N2O from agricultural soils. As such, shifts to agricultural management practices that increase the number of earthworms require an understanding of the role of earthworms in N2O dynamics. We conducted a field experiment to examine the effects of addition of anecic earthworms (Lumbricus terrestris on N2O flux in a field previously planted with corn (Zea mays in southern Rhode Island, USA. Plots were amended with (15NH42SO4 and either 0 (CTL or 48 L. terrestris m-2 (EW. The flux of N2O, 15N2O and 15N2 was measured over 28 days between October and November 2008. The EW treatment had a significantly higher flux of N2O and 15N2O 1 - 3 days after 15NH4 addition. No treatment effects were observed on 15N2 flux. The addition of earthworms significantly increased (Day 1 and decreased (Day 12 the mole fraction of N2O relative to the CTL. Our results suggest that anecic earthworm additions can increase N2O flux from inorganic fertilizer N amendments, but the effects appear to short-lived.

José A. Amador

2013-05-01

 
 
 
 
281

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

Directory of Open Access Journals (Sweden)

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: 556–565, 2012].

Arnauth Martinez GUÉI, Yannick BAIDAI, Jérôme Ebagnerin TONDOH,Jeroen HUISING

2012-08-01

282

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

Directory of Open Access Journals (Sweden)

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 Minhocários são normalmente feitoshorizontalmente sendo necessária uma área grande. A fim de minimizar o tamanho da cultura de minhocas e a possibilidade de ser aplicado em residências, este trabalho propõe avaliar as condições de vermicompostagem vertical. Para isso, foram adquiridas caixas verticais e matéria orgânica. Foram usadas minhocas da espécie Eisenia andrei, minhocas vermelhas da califórmia. Foi avaliada a adaptação das minhocas e caracterização físico-química do húmus gerado. Os resultados mostraram que houve uma boa adaptação das minhocas nesta configuração, minimizando o espaço utilizado, e é uma técnica de reciclagem ecológica de resíduos orgânicos, a criação de umbioproduto o qual pode ser usado como adubo.

Lucélia Hoehne

2013-01-01

283

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

Directory of Open Access Journals (Sweden)

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 17.6–23.8% 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.

K. Parthasarathi

2013-11-01

284

The freeze-thaw stress response of the yeast Saccharomyces cerevisiae is growth phase specific and is controlled by nutritional state via the RAS-cyclic AMP signal transduction pathway.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The ability of cells to survive freezing and thawing is expected to depend on the physiological conditions experienced prior to freezing. We examined factors affecting yeast cell survival during freeze-thaw stress, including those associated with growth phase, requirement for mitochondrial functions, and prior stress treatment(s), and the role played by relevant signal transduction pathways. The yeast Saccharomyces cerevisiae was frozen at -20 degrees C for 2 h (cooling rate, less than 4 degr...

1997-01-01

285

Macropores and earthworm species affected by agronomic intensification  

DEFF Research Database (Denmark)

Soil ecosystem services depend on water regulation both to retain soil moisture and to eliminate water excess without harmful loss of particles and nutrients. As such the combination of soil physical properties that support soil hydrological functioning is a well-recognized service delivered by 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. Biopores and soil aggregate formation have been shown to be crucial results of soil macroorganism activities contributing to soil hydrology. In collaboration between the French â??Observatoire de Recherche en Environnement â?? Agro-écosystèmes, Cycles Biogéochimiques et Biodiversitéâ? (ORE-ACBB) and the FP7 EU project EcoFINDERS we investigated the relationsship between earthworm biodiversity, macropores and three agricultural landuse types. A field campaign was conducted in October-November 2011. Earthworm burrow distribution was quantified at 10, 20, 30, 50 and 100 20 cm horizontal layer intervals down the 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 (Ã?) less than 5 mm were significantly more abundant in permanent grassland compared to conventional rotation system with annual crops. An intermediate system with 3 year grass and 3 years with annuals was also intermediate between the two other systems. At 30 cm's depth we found no large macropores, Ã? >7 mm, in the system with annuals, but increasingly more in rotations with grass. Addition of frequencies of macropores with Ã?>7 mm retains the significant difference between annual and the permanent grass system. Moreover, all the large burrows, >5 mm Ã?, follow this pattern and are significantly more numerous in permanent grass to annuals (P<3%). At depth 100 cm total number of macropores were more abundant in the annual crops compared with permanent grass (P=5%), due to a larger number of macropores <7 mm. We present an interpretation of the macropore patterns in relation to the anecic and endogeic lifeforms and their established role in creating burrows of different spatial distribution and density.

Krogh, Paul Henning; Pérès, Guénola

286

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

Science.gov (United States)

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

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

2014-07-01

287

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

Energy Technology Data Exchange (ETDEWEB)

Background. Earthworm heavy metal concentrations (critical body residues, CBRs) may be the most relevant measures of heavy metal bioavailability in soils and may be linkable to toxic effects in order to better assess soil ecotoxicity. However, as earthworms possess physiological mechanisms to secrete and/or sequester absorbed metals as toxicologically inactive forms, total earthworm metal concentrations may not relate well with toxicity. Objective. The objectives of this research were to: i) develop LD{sub 50}s (total earthworm metal concentration associated with 50% mortality) for Cd, Pb, and Zn; ii) evaluate the LD{sub 50} for Zn in a lethal Zn-smelter soil; iii) evaluate the lethal mixture toxicity of Cd, Pb, and Zn using earthworm metal concentrations and the toxic unit (TU) approach; and iv) evaluate total and fractionated earthworm concentrations as indicators of sublethal exposure. Methods. Earthworms (Eisenia fetida (Savigny)) were exposed to artificial soils spiked with Cd, Pb, Zn, and a Cd-Pb-Zn equitoxic mixture to estimate lethal CBRs and mixture toxicity. To evaluate the CBR developed for Zn, earthworms were also exposed to Zn-contaminated field soils receiving three different remediation treatments. Earthworm metal concentrations were measured using a procedure devised to isolate toxicologically active metal burdens via separation into cytosolic and pellet fractions. (orig.)

Conder, J.M.; Lanno, R.P. [Oklahoma State Univ., Dept. of Zoology, Stillwater, OK (United States)

2003-07-01

288

Earthworm activity affecting organic matter, aggregation and microbial activity in soils restored after opencast mining for coal  

Energy Technology Data Exchange (ETDEWEB)

The paper describes the results of introducing earthworms into physically degraded soils restored after opencast coal mining. Their effects on soil organic matter and associated soil aggregation were then measured after a period of 9 yr. Earthworm inputs increased stable aggregation and resulted in a high proportion of the soil organic matter as carbohydrates. Although the total amount of organic matter in the top 15 cm was unaffected by the presence of earthworms, there was some redistribution to depth. Earthworms also caused an increase in the carbon content of the clay-sized fraction. There was evidence of organic matter having greater efficiency in stabilising aggregates where earthworms were abundant. Earthworm activity increased soil microbial biomass near the surface but caused a decrease at depth. Metabolic quotient was lower near the surface but higher at depth in soils with earthworms; mineralisation constants were lower in soils with earthworms at both sampling depths. Overall, the results emphasise the important influence of earthworm activity on aggregate and organic matter stabilisation, processes which are closely linked.

Scullion, J.; Malik, A. [University of Wales, Aberystwyth (United Kingdom). Soil Science Unit, Inst. of Biological Sciences

2000-01-01

289

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)

2013-02-24

290

Freeze Technology for Nuclear Applications - 13590  

Energy Technology Data Exchange (ETDEWEB)

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)

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

2013-07-01

291

Beneficial effects of freezing rate determined by indirect thermophysical calculation on cell viability in cryopreserved tissues.  

Science.gov (United States)

Many types of mammalian cells, such as sperm, blood, embryos, etc., have been successfully cryopreserved for the last few decades, while no optimal method for the cryopreservation of mammalian tissues or organs has been established, showing a poor survival after thawing with a low recovery of function. In this study, the freezing rate was determined by indirect thermodynamic calculation, and its potential effect on the cryoprotection of human saphenous veins and tissue-engineered bones was investigated. The vein segments were frozen according to the calculated freezing rate, using rate-controlled freezing devices, with a freezing solution composed of 10% dimethylsulphoxide and 20% fetal bovine serum in RPMI 1640 media. The efficacy of indirect calculation was assessed by the cell viability measured using fluorescence double-staining methods. The results indicated that the freezing rate determined by indirect calculation significantly (P thaw cellular viability of the blood vessel, particularly in terms of the endothelial cells. However, it exerted relatively less protective effect on the osteoblastic cell-cultured scaffolds. These results suggest that freezing-induced injuries may occur in tissues, and the freezing rate determined by indirect thermophysical calculation can be used for the optimization of tissue cryopreservation by minimizing the injuries. PMID:16537175

Han, Dong-Wook; Park, Han-Ki; Park, Young Hwan; Kim, Taek-Soo; Yoon, Woong-Sub; Kim, Jeong Koo; Park, Jong-Chul

2006-01-01

292

Exact theory of freeze out  

CERN Document Server

By considering the kinetic equations for the relic particles and the bath particles supposed in thermal and chemical equilibrium in the early Universe, we show that the problem of finding the present relic abundance is exactly defined by a system of two equations, the usual Boltzmann equation and a new one previously not recognized. The analytical solution of the latter gives the abundance down to a matching temperature that can be identified with freeze out temperature $x_f=m/T_f$, while the usual Boltzmann equation is valid only for $x \\ge x_f$. The dependence of the present relic abundance on the abundance at an intermediate temperature is an exact result and not the consequence of the so called freeze out approximation. We also suggest an analytical approximation that furnishes the relic abundance accurate at the level of $1\\%-2\\%$ in the case of $S$-wave and $P$-wave scattering cross sections.

Cannoni, Mirco

2014-01-01

293

Comparative Genotoxicity of Cadmium and Lead in Earthworm Coelomocytes  

International Nuclear Information System (INIS)

To determine genotoxicity to coelomocytes, Pheretima peguana earthworms were exposed in filter paper studies to cadmium (Cd) and lead (Pb) for 48 h, at concentrations less than the LC10 Cd: 0.09, 0.19, 0.38, 0.75, and 1.50 ?g cm-2; Pb: 1.65, 3.29, 6.58, 13.16, and 26.32 ?g cm-2. For Cd at 0.75 ?g cm-2, in the micronucleus test (detects chromosomal aberrations), significant increases (P-2. This study shows that Cd is more acutely toxic and sublethally genotoxic than Pb to P. peguana. Cadmium caused chromosomal aberrations and DNA single-strand breaks at 45% of the LC10 concentration. Lead, in contrast, did not induce DNA damage but caused cytokinesis defects.

2011-01-01

294

Earthworms newly from Mongolia (Oligochaeta, Lumbricidae, Eisenia  

Directory of Open Access Journals (Sweden)

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 Bouché, 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.

Robert Blakemore

2013-04-01

295

Escape and avoidance learning in the earthworm Eisenia hortensis.  

Science.gov (United States)

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

Wilson, W Jeffrey; Ferrara, Nicole C; Blaker, Amanda L; Giddings, Charisa E

2014-01-01

296

Can Earthworm "mix up" Soil Carbon Budgets in Temperate Forests Under Elevated Carbon Dioxide?  

Science.gov (United States)

The effects of global change on earthworms and their associated feedbacks on soil and ecosystem processes have been largely overlooked. We studied how the responses of a temperate deciduous forest to elevated carbon dioxide atmospheric concentrations (e[CO2]) influence earthworms and the soil processes affected by them. Our objectives were to: i) identify soil layers of active soil mixing under e[CO2] and current carbon dioxide atmospheric concentrations (c[CO2]) using fallout cesium (137Cs), ii) study how e[CO2] affects earthworm populations, iii) understand the relationship between soil mixing and earthworms at our study site, and iv) identify the implications of earthworm-mediated soil mixing for the carbon budget of a temperate forest. To study soil mixing, we measured vertical 137Cs activity in soil cores (0-24 cm depth) collected in replicated e[CO2] and c[CO2] sweetgum (Liquidambar styraciflua) plots (n = 2) in a Free Air CO2 Enrichment (FACE) ecosystem experiment at Oak Ridge National Laboratory. We measured earthworm density and fresh weight in the plots in areas adjacent to where soil cores were taken. Preliminary results on the vertical distribution of 137Cs in the c[CO2] treatments showed that higher 137Cs activity was located from 8-16 cm depth and no 137Cs activity was measured below 20 cm. In contrast, in the e[CO2] treatment, peak 137Cs activity was slightly deeper (10-18 cm), and 137Cs activity was still measured below 22 cm. Mean earthworm density was higher in e[CO2] than c[CO2] treatments (168 m-2 and 87 m-2, respectively; p = 0.046); earthworm fresh weights, however, did not differ significantly between treatments (32 g m-2 and 18 g m-2, respectively; p = 0.182). The 137Cs vertical distribution suggest that soil mixing occurs deeper in e[CO2] than in c[CO2] treatments, which is consistent with higher earthworm densities in e[CO2] than in c[CO2] treatments. Mixing deeper low carbon content soil with shallower high carbon soil may result in a dilution of net carbon inputs in forest soils exposed to e[CO2]. Vertical dilution of new carbon may explain why carbon accrual is detected only near the surface at this FACE site. By identifying the depths of active soil mixing and possible soil mixing mechanisms (e.g. earthworms), accounting of new organic carbon accrual could be more reliably determined for forest soils in response to e[CO2] conditions.

Sánchez-de León, Y.; González-Meler, M.; Sturchio, N. C.; Wise, D. H.; Norby, R. J.

2008-12-01

297

Up-regulation of acidic ribosomal phosphoprotein P0 in response to freezing or anoxia in the freeze tolerant wood frog, Rana sylvatica.  

Science.gov (United States)

Natural freezing survival by the wood frog, Rana sylvatica, involves multiple organ-specific, freeze-responsive changes in gene expression. The present study provides the first report of freeze-responsive genes in brain. Differential screening of a cDNA library made from brain of frozen wood frogs revealed a freeze-responsive clone encoding a protein of 315 amino acids that was identified as the acidic ribosomal phosphoprotein, P0 (GenBank Accession No. AF176302). The amino acid sequence showed 91-92% identity with the protein from other vertebrates. Thirteen unique amino acid substitutions occurred as compared with mammalian or avian P0 sequences; these may represent structural differences that support protein function at low body temperature. Transcripts of P0 rose by 8-fold in brain of frogs frozen for 24 h at -2.5 degrees C, compared with controls at 5 degrees C, and reached 12-fold higher in 24 h thawed frogs. Immunoblotting showed that P0 protein increased by approximately 3-fold in brain during freezing and remained high after thawing. Freeze up-regulation of P0 was largely brain-specific; transcript levels were unaffected in skeletal muscle and skin and, although transcripts rose approximately 2-fold in liver of frozen frogs, liver P0 protein was unchanged (although P0 protein was much higher overall in liver than in brain). P0 transcripts in wood frog brain were also elevated during anoxia exposure (by approximately 4-fold), but did not change under dehydration stress. The gene was similarly up-regulated under anoxia in brain of the freeze intolerant leopard frog, Rana pipiens. This suggests that P0 expression responds to anoxia stress during freezing. Changes in P0 content in ribosomes may contribute to altered patterns of protein synthesis under anoxia or ischemia. PMID:15710371

Wu, Shaobo; Storey, Kenneth B

2005-02-01

298

Contact freezing: a review of experimental studies  

Directory of Open Access Journals (Sweden)

Full Text Available This manuscript compiles both theoretical and experimental information on contact freezing with the aim to better understand this potentially important but still not well quantified heterogeneous freezing mode. There is no complete theory that describes contact freezing and how the energy barrier has to be overcome to nucleate an ice crystal by contact freezing. Experiments on contact freezing conducted using the cold plate technique indicate that it can initiate ice formation at warmer temperatures than immersion freezing. Additionally, a qualitative difference in the freezing temperatures between contact and immersion freezing has been found using different instrumentation and different ice nuclei. There is a lack of data on collision rates in most of the reported data, which inhibits a quantitative calculation of the freezing efficiencies. Thus, new or modified instrumentation to study contact nucleation in the laboratory and in the field are needed to identify the conditions at which contact nucleation could occur in the atmosphere. Important questions concerning contact freezing and its potential role for ice cloud formation and climate are also summarized.

L. A. Ladino Moreno

2013-10-01

299

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)

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 2×5 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.

F. S. Moosavi

2011-01-01

300

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

Science.gov (United States)

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

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

2009-08-01

 
 
 
 
301

Characteristics of sugar surfactants in stabilizing proteins during freeze-thawing and freeze-drying.  

Science.gov (United States)

Sugar surfactants with different alkyl chain lengths and sugar head groups were compared for their protein-stabilizing effect during freeze-thawing and freeze-drying. Six enzymes, different in terms of tolerance against inactivation because of freeze-thawing and freeze-drying, were used as model proteins. The enzyme activities that remained after freeze-thawing and freeze-drying in the presence of a sugar surfactant were measured for different types and concentrations of sugar surfactants. Sugar surfactants stabilized all of the tested enzymes both during freeze-thawing and freeze-drying, and a one or two order higher amount of added sugar surfactant was required for achieving protein stabilization during freeze-drying than for the cryoprotection. The comprehensive comparison showed that the C10-C12 esters of sucrose or trehalose were the most effective through the freeze-drying process: the remaining enzyme activities after freeze-thawing and freeze-drying increased at the sugar ester concentrations of 1-10 and 10-100 ?M, respectively, and increased to a greater extent than for the other surfactants at higher concentrations. Results also indicate that, when a decent amount of sugar was also added, the protein-stabilizing effect of a small amount of sugar ester through the freeze-drying process could be enhanced. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci. PMID:24797557

Imamura, Koreyoshi; Murai, Katsuyuki; Korehisa, Tamayo; Shimizu, Noriyuki; Yamahira, Ryo; Matsuura, Tsutashi; Tada, Hiroko; Imanaka, Hiroyuki; Ishida, Naoyuki; Nakanishi, Kazuhiro

2014-06-01

302

Freezing Light via hot gases  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We prove that it is possible to freeze a light pulse (i.e., to bring it to a full stop) or even to make its group velocity negative in a coherently driven Doppler broadened atomic medium via electromagnetically induced transparency (EIT). This remarkable phenomenon of the ultra-slow EIT polariton is based on the spatial dispersion of the refraction index $n(\\w,k)$, i.e., its wavenumber dependence, which is due to atomic motion and provides a negative contribution to the grou...

Kocharovskaya, Olga; Rostovtsev, Yuri; Scully, Marlan O.

2000-01-01

303

Repeatability and randomness in heterogeneous freezing nucleation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This study is aimed at clarifying the relative importance of the specific character of the nuclei and of the duration of supercooling in heterogeneous freezing nucleation by immersed impurities. Laboratory experiments were carried out in which sets of water drops underwent multiple cycles of freezing and melting. The drops contained suspended particles of mixtures of materials; the resulting freezing temperatures ranged from ?6°C to ?24°C. Rank correlation coefficients between observed free...

Vali, G.

2008-01-01

304

Interdependence of Measures in Pavlovian Conditoned Freezing  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Wood, Suzanne C.; Anagnostaras, Stephan G.

2011-01-01

305

Atmospheric freeze drying assisted by power ultrasound  

Digital Repository Infrastructure Vision for European Research (DRIVER)

[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...

Santacatalina Bonet, Juan Vicente; Carcel Carrio?n, Juan Andre?s; Garci?a Pe?rez, Jose? Vicente; Mulet Pons, Antonio; Simal, S.

2012-01-01

306

A computer controlled analysis of freezing behaviour.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The conditioned freezing response in rats has been much used both by psychologists and neuroscientists to investigate the behavioural effects of brain lesions and of changes in motivational state. The primary advantage of the freezing response is that it can be used without motivational manipulations such as food or water deprivation. Previously, freezing has been measured by a human observer either from video recordings or during the test sessions themselves. But these methods of data collec...

1998-01-01

307

Hot big bang or slow freeze?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We confront the hot 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 slow freeze picture the masses of elementary particles increase and the gravitational constant decreases with cosmic time, while the Newtonian attraction remains unchanged. The slow freeze and hot big bang pictures both describe the same observations or physical reality. We present a simple three-parameter "crossover mo...

Wetterich, C.

2014-01-01

308

Assessing soil ecotoxicity of methyl tert-butyl ether using earthworm bioassay; closed soil microcosm test for volatile organic compounds  

Energy Technology Data Exchange (ETDEWEB)

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.

An, Youn-Joo [Department of Environmental Science, Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul 143-701 (Korea, Republic of)]. E-mail: anyjoo@konkuk.ac.kr

2005-03-01

309

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

2005-03-01

310

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

2014-01-01

311

DNA damage in earthworms from highly contaminated soils: assessing resistance to arsenic toxicity by use of the Comet assay.  

Science.gov (United States)

Earthworms native to the former mine site of Devon Great Consols (DGC), UK reside in soils highly contaminated with arsenic (As). These earthworms are considered to have developed a resistance to As toxicity. The mechanisms underlying this resistance however, remain unclear. In the present study, non-resistant, commercially sourced Lumbricus terrestris were exposed to a typical DGC soil in laboratory mesocosms. The earthworms bio-accumulated As from the soil and incurred DNA-damage levels significantly above those observed in the control mesocosm (assessed using the Comet assay). A dose response was observed between DNA damage (% tail DNA) and As concentration in soil (control, 98, 183, 236, 324 and 436mgkg(-1)). As-resistant earthworms (Lumbricus rubellus, Dendrodrilus rubidus and L. terrestris) collected from contaminated soils at DGC (203 to 9025mgkg(-1) As) had also bio-accumulated high levels of As from their host soils, yet demonstrated low levels of DNA damage compared with earthworms from uncontaminated sites. The results demonstrate that the As-contaminated soils at DGC are genotoxic to non-native earthworms and much less so to earthworms native to DGC, thus providing further evidence of an acquired resistance to As toxicity in the native earthworms. PMID:20015476

Button, Mark; Jenkin, Gawen R T; Bowman, Karen J; Harrington, Chris F; Brewer, Tim S; Jones, George D D; Watts, Michael J

2010-02-01

312

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)

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.

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

313

Effects of metal pollution on earthworm communities in a contaminated floodplain area: Linking biomarker, community and functional responses  

Energy Technology Data Exchange (ETDEWEB)

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.

Gestel, Cornelis A.M. van [Institute of Ecological Science, VU University, De Boelelaan 1085, 1081 HV Amsterdam (Netherlands)], E-mail: kees.van.gestel@falw.vu.nl; Koolhaas, Josee E. [Institute of Ecological Science, VU University, De Boelelaan 1085, 1081 HV Amsterdam (Netherlands); Hamers, Timo [Institute of Environmental Studies, VU University, De Boelelaan 1085, 1081 HV Amsterdam (Netherlands); Hoppe, Maarten van; Roovert, Martijn van; Korsman, Cora [Institute of Ecological Science, VU University, De Boelelaan 1085, 1081 HV Amsterdam (Netherlands); Reinecke, Sophie A. [Department of Botany and Zoology, University of Stellenbosch, Private bag X1, Matieland 7602 (South Africa)

2009-03-15

314

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

2013-08-01

315

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

Science.gov (United States)

Through transformation of plant litter into soil organic matter (SOM) and translocation of ingested organic material among different soil depths, soil organisms, especially earthworms, are one of the major factors affecting SOM dynamics. In North America temperate soil, historical human activity has lead to invasion of European earthworms into habitats that were previously earthworm-free or inhabited only by native species. By consuming leaf litter and SOM, burrowing, and casting, invasive earthworms have been known for reducing the understory vegetation and leaf litter layer while increasing the thickness of organic soil, causing changes in the soil habitat and the distribution of SOM. Recently, another group of invasive earthworm, namely Amynthas from Asia, has been reported invading habitats already dominated by European species, causing a 'second wave of invasion' where the soil ecosystem, already modified by European species, is going through another transition. The mechanisms through which these functionally (ecologically) different species affect C and N transformation could be better understood by tracing the carbon and nitrogen derived from 13C- and 15N-labeled leaf litter into earthworm tissues and SOM. The objective of this study is to understand how earthworm species that differ ecologically, including the Asian Amynthas, interact with each other and how these interactions affect SOM dynamics. We hypothesized that 1) species feeding on different food resources will have different isotopic signature and their tissue 13C and 15N values will change due to facilitation or interspecific competition on food resources, and 2) the short-term fate of litter-derived carbon differs depending on the presence or absence of different earthworm species. These hypotheses were tested by field sampling and lab mesocosm experiments using 13C and 15N double-enriched Tulip Poplar leaf litter (mean 13C = 124‰, mean 15N = 1667‰) produced from tree saplings growing in an airtight chamber. Stable isotope mass balance calculation is used to estimate the recovery of litter-derived carbon from three pools (earthworm tissue, SOM, remaining litter), the loss of litter-derived carbon through soil respiration, and the contribution of different carbon sources to soil CO2 efflux in different earthworm treatments. Our results show that earthworm species recognized as 'soil feeders' have 13C and 15N values that are 1.2‰ and 3.8‰ higher than those of 'litter feeders', and 15N also differ significantly amount different soil feeders, suggesting different food resource usage even within the same functional group. There are strong species effects on both leaf litter disappearance rate and CO2 efflux rate, both being high when Amynthas earthworms are present. Our results suggest that changing earthworm species composition leads to changing resource use, which alters the fate of organic carbon in the forest floor and soil and could potentially affect long-term SOM dynamics in temperate forests.

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

2013-12-01

316

Putrescine is involved in Arabidopsis freezing tolerance and cold acclimation by regulating Abscisic acid levels in response to low temperature  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The levels of endogenous polyamines have been shown to increase in plant cells challenged with low temperature; however, the functions of polyamines in the regulation of cold stress responses are unknown. Here, we show that the accumulation of putrescine under cold stress is essential for proper cold acclimation and survival at freezing temperatures because Arabidopsis (Arabidopsis thaliana) mutants defective in putrescine biosynthesis (adc1, adc2) display reduced freezing tolerance compared ...

2008-01-01

317

Cryoprotectant Biosynthesis and the Selective Accumulation of Threitol in the Freeze-tolerant Alaskan Beetle, Upis ceramboides*  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Adult Upis ceramboides do not survive freezing in the summer but tolerate freezing to ?60 °C in midwinter. The accumulation of two cryoprotective polyols, sorbitol and threitol, is integral to the extraordinary cold-hardiness of this beetle. U. ceramboides are the only animals known to accumulate high concentrations of threitol; however, the biosynthetic pathway has not been studied. A series of 13C-labeled compounds was employed to investigate this biosynthetic pathway using 13C{1H} NMR s...

Walters, Kent R.; Pan, Qingfeng; Serianni, Anthony S.; Duman, John G.

2009-01-01

318

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

Science.gov (United States)

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

Ruiz, Siul; Or, Dani; Schymanski, Stanislaus

2014-05-01

319

[Effects of earthworm activity on phosphorus fraction and available phosphorus content in red soil].  

Science.gov (United States)

By the methods of incubation test and Hedley's phosphorus fractionation, this paper studied the effects of inoculating earthworm (Pheretinma pingi) on the phosphorus fractions and available phosphorus contents in red soil. The results showed that during a 100-day incubation, earthworm inoculation combined with organic materials (rice straw RS, peanut residue PR, and rape residue RR) amendment increased significantly the content of soil available phosphorus. Statistics analysis showed that there was a significant difference in soil available phosphorus content between treatments PR or RR with and without earthworm inoculation. Compared with the contents of anion-exchange resin P(trace), NaCO3-soluble P(14.5 mg x kg(-1)) and microbial P(1.0 mg x kg(-1)) in CK, those in treatments of earthworm inoculation plus organic materials amendment increased to 10.5 - 17.8 mg kg(-1), 23.5-35.6 mg x kg(-1), and 6.8 - 9.7 mg x kg(-1), respectively, organic phosphorus content enhanced from 37.9 mg x kg(-1) to 50.7-59.3 mg x kg(-1), whereas residual P was reduced. Earthworm performed an activated effect on the availability of phosphorus in red soil. PMID:16422511

Liu, Dehui; Hu, Feng; Hu, Pei; Cheng, Jiemin

2005-10-01

320

A dataset comprising four micro-computed tomography scans of freshly fixed and museum earthworm specimens  

Science.gov (United States)

Background Although molecular tools are increasingly employed to decipher invertebrate systematics, earthworm (Annelida: Clitellata: ‘Oligochaeta’) taxonomy is still largely based on conventional dissection, resulting in data that are mostly unsuitable for dissemination through online databases. In order to evaluate if micro-computed tomography (?CT) in combination with soft tissue staining techniques could be used to expand the existing set of tools available for studying internal and external structures of earthworms, ?CT scans of freshly fixed and museum specimens were gathered. Findings Scout images revealed full penetration of tissues by the staining agent. The attained isotropic voxel resolutions permit identification of internal and external structures conventionally used in earthworm taxonomy. The ?CT projection and reconstruction images have been deposited in the online data repository GigaDB and are publicly available for download. Conclusions The dataset presented here shows that earthworms constitute suitable candidates for ?CT scanning in combination with soft tissue staining. Not only are the data comparable to results derived from traditional dissection techniques, but due to their digital nature the data also permit computer-based interactive exploration of earthworm morphology and anatomy. The approach pursued here can be applied to freshly fixed as well as museum specimens, which is of particular importance when considering the use of rare or valuable material. Finally, a number of aspects related to the deposition of digital morphological data are briefly discussed.

2014-01-01

 
 
 
 
321

Enantioselective acute toxicity and bioaccumulation of benalaxyl in earthworm (Eisenia fedtia).  

Science.gov (United States)

The enantioselectivities of individual enantiomers of benalaxyl in acute toxicity and bioaccumulation in earthworm ( Eisenia fedtia ) were studied. The acute toxicity was tested by paper contact test. After 48 h of exposure, the calculated LC(50) values of the R-(-)-form, rac-form, and S-(+)-form were 4.99, 5.08, and 6.66 microg/cm(2), respectively. After 72 h of exposure, the calculated LC(50) values were 1.23, 1.73, and 2.45 microg/cm(2), respectively. Therefore, the acute toxicity of benalaxyl enantiomers was enantioselective. A method for determining residues of the two enantiomers of benalaxyl in earthworm tissue by high-performance liquid chromatography based on cellulose tri-(3,5-dimethylphenyl-carbamate) chiral stationary phase was developed. During the bioaccumulation experiment, the enantiomer fraction in earthworm tissue was maintained approximately at 0.6, whereas enantiomer fraction in spiked soil was maintained at 0.5; in other words, the bioaccumulation of benalaxyl was enantioselective in earthworm tissue. Peak-shaped accumulation curves were observed for both enantiomers, and the calculated biota to soil accumulations (kg dry kg(-1) wet weight) at steady state were below 1 for both enantiomers. During the elimination experiment, 79.0% of R-(-)-enantiomer and 89.6% of S-(+)-enantiomer in earthworm tissue were eliminated within 2 days. PMID:19694444

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

2009-09-23

322

Avoidance of Cu- and Zn-contaminated soil by three ecologically different earthworm species.  

Science.gov (United States)

Earthworm avoidance response to soils contaminated with harmful substances has been proposed as a potential tool for assessing soil toxicity with low test effort. In the present study, the objective was to find out whether three ecologically different earthworm species, Aporrectodea tuberculata (Eisen), Lumbricus rubellus (Hoffmeister), and Dendrobaena octaedra (Savigny), avoid soils simultaneously spiked with Cu and Zn. In addition, metal-contaminated field soil taken close to a Cu-Ni smelter was tested with A. tuberculata using a two-section avoidance lest procedure. All three earthworm species clearly avoided Cu/Zn contaminated soil but differently: D. octaedra was the most sensitive species, responding to low metal concentrations, whereas L. rubellus responded only to the highest metal concentration tested, being the least sensitive species. Moreover, A. tuberculata showed clear avoidance response to the metal contaminated field soil. In conclusion, the results indicate that earthworm avoidance behavior is an ecologically relevant parameter for assessing harmfulness of metal contaminated soils, both spiked and field-contaminated soils. However, it is important to consider the specific species to be used in the earthworm avoidance test procedure. PMID:15978289

Lukkari, Tuomas; Haimi, Jari

2005-09-01

323

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

2013-08-01

324

[Effects of different vegetation restoration of degraded red soil on earthworm population dynamics].  

Science.gov (United States)

This study was conducted at the long-term experimental plots in Ecological Experimental Station of Red Soil in Yujiang County (28 degrees 15'30''N, 116 degrees 55'30''E ), Jiangxi Province, subtropical China. Earthworm population was investigated seasonally from May 1999 to February 2000, under different vegetations including four artificial woodlands [deciduous broadleaf woodland (Quercus chenii, Qc), evergreen broadleaf woodland (Schima superba, Ss), coniferous woodland (Pinus massonina, Pm) and mixed woodland (Schima superba-Pinus massonina, Sm)], two grasslands [gently-disturbed grassland (G1), undisturbed grassland (G2)] and control wasteland (CK). The results indicated that the population structure was very simple. Only Drawinda gisti characterized by pioneer was found. The seasonal averages of density and biomass were in the order of G2 > G1 > Qc > Ss > Pm > Sm > CK, and those of G2, G1 and Qc were significantly higher than those of the latters (P stability, followed by Sm and Ss, and G1, G2, and Pm had the lowest stability. The overall differentiation of earthworm population could be drawn through canonical discriminant analysis. There were significant correlations between earthworms and some soil properties (P < 0.01). Overall, the differentiation of earthworm population was driven by the quantity and quality of soil organic matter returned by the vegetations. Additionally, based on earthworm population, the importance of selecting appropriate vegetation types during the restoration of degraded red soil was emphasized. PMID:15707332

Liu, Manqiang; Hu, Feng; Chen, Xiaoyun; He, Yuanqiu; Li, Huixin

2004-11-01

325

Earthworm succession in afforested colliery spoil heaps in the Sokolov region, Czech Republic  

Energy Technology Data Exchange (ETDEWEB)

Earthworm communities were studied at six heap sites representing a chronosequence of Alnus glutinosa (black alder) stands (age 3-62 years) and compared with those on an unameliorated heap and in an alder stand (60 years old) on natural soil. Spoil heaps in the open-cast coal mining area near Sokolov (north-western Bohemia) were mainly reclaimed using afforestation. No earthworms were found on the virgin heap. Young plots were colonized by euryecious epigeic earthworms (i.e., those living above soil surface), but higher proportions of endogeic species (i.e., soil dwellers), did not appear until after more than 30 years of succession. The density and biomass of earthworms increased from the youngest stand (67 individuals/m{sup 2}; 5 g/m{sup 2}) to the older ones (e.g., 407 ind/m{sup 2}; 13 g/m{sup 2} in the 23-year-old stand). However, both parameters were low in the oldest stand (35 ind/m{sup 2}; 3 g/m{sup 2}), but this may have been the result of extensive soil disturbance. Earthworm populations were often higher in reclaimed sites than in the control alder stand (150 ind/m{sup 2}; 7 g/m{sup 2}). However, the community structures were different, with the control being dominated by the litter-feeding species, Dendrobaena vejdovskyi.

Pizl, V. [Academy of Sciences of the Czech Republic, Ceske Budejovice (Czech Republic). Inst. Soil Biology

2001-07-01

326

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

Energy Technology Data Exchange (ETDEWEB)

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

Goven, A.J.; Fitzpatrick, L.C. (Univ. of North Texas, Denton (United States)); Eyambe, G.S. (Texas Tech Univ., Lubbock (United States)); Venables, B.J. (TRAC Labs., Denton, TX (United States)); Cooper, E.L. (Univ. of California, Los Angeles (United States))

1993-05-01

327

Earthworms and structure rehabilitation in subsoils and in topsoils affected by opencast mining for coal  

Energy Technology Data Exchange (ETDEWEB)

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.

Stewart, V.I.; Scullion, J.; Salih, R.O.; Al-Bakri, K.H.

1988-01-01

328

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

2013-09-01

329

Synchrotron X-Ray Visualisation of Ice Formation in Insects during Lethal and Non-Lethal Freezing  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Although the biochemical correlates of freeze tolerance in insects are becoming well-known, the process of ice formation in vivo is subject to speculation. We used synchrotron x-rays to directly visualise real-time ice formation at 3.3 Hz in intact insects. We observed freezing in diapausing 3rd instar larvae of Chymomyza amoena (Diptera: Drosophilidae), which survive freezing if it occurs above ?14°C, and non-diapausing 3rd instar larvae of C. amoena and Drosophila melanogaster (Diptera: ...

2009-01-01

330

Recrystallization in a Freezing Tolerant Antarctic Nematode, Panagrolaimus davidi, and a Alpine Weta, Hemideina maori (Orthoptera; Stenopelmatidae)  

DEFF Research Database (Denmark)

The ability of haemolymph from the freezing tolerant weta,Hemideina maori,and supernatant from homogenates of the freezing tolerant nematodePanagrolaimus davidito inhibit the recrystallization of ice was examined using the â??splat freezingâ? technique and annealing on a cryomicroscope stage. There was no recrystallization inhibition in weta haemolymph or in insect ringer controls. Recrystallization inhibition was present in the nematode supernatant but this was destroyed by heating and was absent in controls.P. davidisurvives intracellular freezing and recrystallization inhibition may be important for the survival of this stress.

Ramløv, Hans; Wharton, David A.

1996-01-01

331

Predicting Arabidopsis Freezing Tolerance and Heterosis in Freezing Tolerance from Metabolite Composition  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Heterosis, or hybrid vigor, is one of the most important tools in plant breeding and has previously been demonstrated for plant freezing tolerance. Freezing tolerance is an important trait because it can limit the geographical distribution of plants and their agricultural yield. Plants from temperate climates increase in freezing tolerance during exposure to low, non-freezing temperatures in a process termed ‘cold acclimation’. Metabolite profiling has indicated a major reprogramming of p...

2010-01-01

332

Remediation of polychlorinated biphenyl-contaminated soil by using a combination of ryegrass, arbuscular mycorrhizal fungi and earthworms.  

Science.gov (United States)

In this work, a laboratory experiment was performed to investigate the influences of inoculation with the arbuscular mycorrhizal fungus (AMF) Glomus caledoniun L. and/or epigeic earthworms (Eisenia foetida) on phytoremediation of a PCB-contaminated soil by ryegrass grown for 180d. Planting ryegrass, ryegrass inoculated with earthworms, ryegrass inoculated with AMF, and ryegrass co-inoculated with AMF and earthworms decreased significantly initial soil PCB contents by 58.4%, 62.6%, 74.3%, and 79.5%, respectively. Inoculation with AMF and/or earthworms increased the yield of plants, and the accumulation of PCBs in ryegrass. However, PCB uptake by ryegrass accounted for a negligible portion of soil PCB removal. The number of soil PCB-degrading populations increased when ryegrass was inoculated with AMF and/or earthworms. The data show that fungal inoculation may significantly increase the remedial potential of ryegrass for soil contaminated with PCBs. PMID:24457052

Lu, Yan-Fei; Lu, Mang; Peng, Fang; Wan, Yun; Liao, Min-Hong

2014-07-01

333

Mutual impacts of wheat (Triticum aestivum L.) and earthworms (Eisenia fetida) on the bioavailability of perfluoroalkyl substances (PFASs) in soil.  

Science.gov (United States)

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. PMID:24158108

Zhao, Shuyan; Fang, Shuhong; Zhu, Lingyan; Liu, Li; Liu, Zhengtao; Zhang, Yahui

2014-01-01

334

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

Energy Technology Data Exchange (ETDEWEB)

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

Weeks, J.M.; Svendsen, C. [NERC, Huntingdon (United Kingdom). Inst. of Terrestrial Ecology

1996-10-01

335

The influence of freezing drizzle on wire icing during freezing fog events  

Science.gov (United States)

Both direct and indirect effects of freezing drizzle on ice accretion were analyzed for ten freezing drizzle events during a comprehensive ice thickness, fog, and precipitation observation campaign carried out during the winter of 2008 and 2009 at Enshi Radar Station (30°17'N, 109°16'E), Hubei Province, China. The growth rate of ice thickness was 0.85 mm h-1 during the freezing drizzle period, while the rate was only 0.4 mm h-1 without sleet and freezing drizzle. The rain intensity, liquid water content (LWC), and diameter of freezing drizzle stayed at low values. The development of microphysical properties of fog was suppressed in the freezing drizzle period. A threshold diameter ( Dc) was proposed to estimate the influence of freezing drizzle on different size ranges of fog droplets. Fog droplets with a diameter less than Dc would be affected slightly by freezing drizzle, while larger fog droplets would be affected significantly. Dc had a correlation with the average rain intensity, with a correlation coefficient of 0.78. The relationships among the microphysical properties of fog droplets were all positive when the effect of freezing drizzle was weak, while they became poor positive correlations, or even negative correlations during freezing drizzle period. The direct contribution of freezing drizzle to ice thickness was about 14.5%. Considering both the direct and indirect effects, we suggest that freezing drizzle could act as a "catalyst" causing serious icing conditions.

Zhou, Yue; Niu, Shengjie; Lü, Jingjing

2013-07-01

336

Drought increases freezing tolerance of both leaves and xylem of Larrea tridentata.  

Science.gov (United States)

Drought and freezing are both known to limit desert plant distributions, but the interaction of these stressors is poorly understood. Drought may increase freezing tolerance in leaves while decreasing it in the xylem, potentially creating a mismatch between water supply and demand. To test this hypothesis, we subjected Larrea tridentata juveniles grown in a greenhouse under well-watered or drought conditions to minimum temperatures ranging from -8 to -24 °C. We measured survival, leaf retention, gas exchange, cell death, freezing point depression and leaf-specific xylem hydraulic conductance (k?). Drought-exposed plants exhibited smaller decreases in gas exchange after exposure to -8 °C compared to well-watered plants. Drought also conferred a significant positive effect on leaf, xylem and whole-plant function following exposure to -15 °C; drought-exposed plants exhibited less cell death, greater leaf retention, higher k? and higher rates of gas exchange than well-watered plants. Both drought-exposed and well-watered plants experienced 100% mortality following exposure to -24 °C. By documenting the combined effects of drought and freezing stress, our data provide insight into the mechanisms determining plant survival and performance following freezing and the potential for shifts in L. tridentata abundance and range in the face of changing temperature and precipitation regimes. PMID:20825578

Medeiros, Juliana S; Pockman, William T

2011-01-01

337

Breeding of Freeze-tolerant Yeast and the Mechanisms of Stress-tolerance  

Science.gov (United States)

Frozen dough method have been adopted in the baking industry to reduce labor and to produce fresh breads in stores. New freeze-tolerant yeasts for frozen dough preparations were isolated from banana peel and identified. To obtain strains that have fermentative ability even after several months of frozen storage in fermented dough, we attempted to breed new freeze-tolerantstrain. The hybrid between S.cerevisiae, which is a isolated freeze-tolerant strain, and a strain isolated from bakers' yeast with sexual conjugation gave a good quality bread made from frozen dough method. Freeze-tolerant strains showed higher surviving and trehalose accumulating abilities than freeze-sensitive strains. The freeze tolerance of the yeasts was associated with the basal amount of intracellular trehalose after rapid degradation at the onset of the prefermentation period. The complicated metabolic pathway and the regulation system of trehalose in yeast cells are introduced. The trehalose synthesis may act as a metabolic buffer system which contribute to maintain the intracellular inorganic phosphate and as a feedback regulation system in the glycolysis. However, it is not known enough how the trehalose protects yeast cells from stress.

Hino, Akihiro

338

Unprecedented Cell-Selection Using Ultra-Quick Freezing Combined with Aquaporin Expression  

Science.gov (United States)

Freezing is usually used for preservation and storage of biological samples; however, this process may have some adverse effects such as cell membrane damage. Aquaporin (AQP), a water channel protein, has been suggested to play some roles for cryopreservation although its molecular mechanism remains unclear. Here we show that membrane damage caused by ultra-quick freezing is rescued by the expression of AQP4. We next examine if the expression of AQP combined with ultra-quick freezing can be used to select cells efficiently under freezing conditions where most cells are died. CHO cells stably expressing AQP4 were exclusively selected from mixed cell cultures. Having identified the increased expression of AQP4 during ES cell differentiation into neuro-ectoderm using bioinformatics, we confirmed the improved survival of differentiated ES cells with AQP4 expression. Finally we show that CHO cells transiently transfected with Endothelin receptor A and Aqp4 were also selected and concentrated by multiple cycles of freezing/thawing, which was confirmed with calcium imaging in response to endothelin. Furthermore, we found that the expression of AQP enables a reduction in the amount of cryoprotectants for freezing, thereby decreasing osmotic stress and cellular toxicity. Taken together, we propose that this simple but efficient and safe method may be applicable to the selection of mammalian cells for applications in regenerative medicine as well as cell-based functional assays or drug screening protocols.

Kato, Yasuhiro; Miyauchi, Takayuki; Abe, Youichiro; Kojic, Dusan; Tanaka, Manami; Chikazawa, Nana; Nakatake, Yuhki; Ko, Shigeru B. H.; Kobayashi, Daisuke; Hazama, Akihiro; Fujiwara, Shoko; Uchida, Tatsuya; Yasui, Masato

2014-01-01

339

Unprecedented cell-selection using ultra-quick freezing combined with aquaporin expression.  

Science.gov (United States)

Freezing is usually used for preservation and storage of biological samples; however, this process may have some adverse effects such as cell membrane damage. Aquaporin (AQP), a water channel protein, has been suggested to play some roles for cryopreservation although its molecular mechanism remains unclear. Here we show that membrane damage caused by ultra-quick freezing is rescued by the expression of AQP4. We next examine if the expression of AQP combined with ultra-quick freezing can be used to select cells efficiently under freezing conditions where most cells are died. CHO cells stably expressing AQP4 were exclusively selected from mixed cell cultures. Having identified the increased expression of AQP4 during ES cell differentiation into neuro-ectoderm using bioinformatics, we confirmed the improved survival of differentiated ES cells with AQP4 expression. Finally we show that CHO cells transiently transfected with Endothelin receptor A and Aqp4 were also selected and concentrated by multiple cycles of freezing/thawing, which was confirmed with calcium imaging in response to endothelin. Furthermore, we found that the expression of AQP enables a reduction in the amount of cryoprotectants for freezing, thereby decreasing osmotic stress and cellular toxicity. Taken together, we propose that this simple but efficient and safe method may be applicable to the selection of mammalian cells for applications in regenerative medicine as well as cell-based functional assays or drug screening protocols. PMID:24558371

Kato, Yasuhiro; Miyauchi, Takayuki; Abe, Youichiro; Koji?, Dušan; Tanaka, Manami; Chikazawa, Nana; Nakatake, Yuhki; Ko, Shigeru B H; Kobayashi, Daisuke; Hazama, Akihiro; Fujiwara, Shoko; Uchida, Tatsuya; Yasui, Masato

2014-01-01

340

Experiences with novel approaches in earthworm testing alternatives  

Energy Technology Data Exchange (ETDEWEB)

Goal, Scope and Background. The earthworm avoidance test is a sensitive screening test. Currently, two test designs, a two-chamber system and a six-chamber system, are under standardization. In the scope of the present study, the two test systems are compared. To assess the results, two procedures are applied, which are based on a threshold value and a statistical method. Moreover, the sensitivity of the avoidance test is compared with the sensitivity of the reproduction test. Methods. The avoidance behaviour of E. fetida towards five chemicals (Cd, Cu, PCP, TBT, TNT) was tested in a sandy and a loamy soil. The ecotoxicological test was performed according to the draft guideline ISO/DIS 17512-1. The results were compared with the number of offspring determined in the reproduction test carried out according to ISO 11268-2. Results and Discussion. The results demonstrate that the avoidance behaviour towards organic chemicals and heavy metals is a suitable screening method showing first tendencies of a chemical's effects on the habitat function of soils. Effects caused by chemical substances become visible at low concentrations and within short test periods. The sensitivity of the reproduction test and the avoidance test is principally comparable; in some cases, the avoidance test showed more sensitive reactions. The dose-response-relationships were more pronounced in the two-chamber test than in the six-chamber-system. Recommendation and Outlook. The two-chamber-system proved to be more feasible than the six-chamber-system. As the sensitivity of the avoidance test and the reproduction test is comparable, the avoidance test can be considered as a suitable screening test. A possible field of application may be the selection of soil samples for which the reproduction assay seems necessary. To assess contaminated or remediated soils, the earthworm reproduction test is recommended as an indicator for the habitat function of the soils. To reduce costs, the avoidance test and the reproduction test could be used as a stepwise system. Thereby, the labour-intensive, but environmentally more relevant reproduction test is carried out only for samples that have already been indicated as toxic in the avoidance test. (orig.)

Hund-Rinke, K.; Lindemann, M.; Simon, M. [Fraunhofer Inst. for Molecular Biology and Applied Ecology, Schmallenberg (Germany)

2005-11-01

 
 
 
 
341

Metal accumulation in the earthworm Lumbricus rubellus. Model predictions compared to field data  

International Nuclear Information System (INIS)

The mechanistic bioaccumulation model OMEGA (Optimal Modeling for Ecotoxicological Applications) is used to estimate accumulation of zinc (Zn), copper (Cu), cadmium (Cd) and lead (Pb) in the earthworm Lumbricus rubellus. Our validation to field accumulation data shows that the model accurately predicts internal cadmium concentrations. In addition, our results show that internal metal concentrations in the earthworm are less than linearly (slope < 1) related to the total concentration in soil, while risk assessment procedures often assume the biota-soil accumulation factor (BSAF) to be constant. Although predicted internal concentrations of all metals are generally within a factor 5 compared to field data, incorporation of regulation in the model is necessary to improve predictability of the essential metals such as zinc and copper. - Earthworm metal concentrations are less than linearly related to total soil concentrations and predicted pore water concentrations

2007-03-01

342

DNA Repair Inhibition by Mercuric Chloride in Earthworms after Exposure to Radiation  

International Nuclear Information System (INIS)

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

2011-10-01

343

DNA Repair Inhibition by Mercuric Chloride in Earthworms after Exposure to Radiation  

Energy Technology Data Exchange (ETDEWEB)

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

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

344

Earthworm avoidance test for soil assessments. An alternative for acute and reproduction tests  

Energy Technology Data Exchange (ETDEWEB)

For ecotoxicological assessments of contaminated or remediated soils pointing to the habitat function of soils for biocenoses, standardized tests with earthworms (acute test, reproduction test) are available among others. Tests used for routine applications should be sensitive and indicate impacts on test organisms after short test periods. The usually applied earthworm tests do not satisfactorily fulfil these criteria. Therefore, in the present work, a behavioural test with earthworms (test criterion: avoidance) was investigated in detail using uncontaminated, artificially contaminated and originally contaminated soils. It was demonstrated that the avoidance behaviour is primarily determined by pollutants, and not by chemical-physical soil properties. The sensitivity of the presented test reaches the sensitivity of established tests. For waste sites, a considerably higher sensitivity was determined. An avoidance behaviour of at least 80% of the worms leaving the soil to be assessed is proposed as a criterion for toxicity. (orig.)

Hund-Rinke, K.; Wiechering, H. [Fraunhofer-Inst. fuer Umweltchemie und Oekotoxikologie, Schmallenberg (Germany)

2001-07-01

345

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

Science.gov (United States)

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

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

2002-05-01

346

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

International Nuclear Information System (INIS)

Scientific literature addressing the influence of pesticides on the growth and reproduction of earthworm is reviewed. Earthworms are considered as important bio indicators 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 bio magnification process of several soil pollutants. Majority of the studies have used mortality as an endpoint rather than subtler endpoints such as reproductive output. It is now emphasized that, whereas higher concentrations of a pollutant can easily be assessed with the acute (mortality) test, contaminated soils with lower (sublethal) pollutant concentrations require more sensitive test methods such as reproduction test in their risk assessment.

2010-01-01

347

Modelling the accumulation of hydrophobic organic chemicals in earthworms. Application of the equilibrium partitioning theory  

Energy Technology Data Exchange (ETDEWEB)

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.)

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

348

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

Energy Technology Data Exchange (ETDEWEB)

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

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

1982-01-01

349

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

Directory of Open Access Journals (Sweden)

Full Text Available 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 conservation and conventional tillage. P. taste showed a population of 328 individuals m-2 during the spring season under conservation tillage. This data coincided with the particle of soil organic matter in the 2 ?m category, high organic carbon content (5, 3 y 2%, total nitrogen (0.3, 0.2 y 0.1% and the depths of 0-10, 10-20 and 20-30 cm, respectively.

Hortensia Brito-Vega

2009-01-01

350

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

Science.gov (United States)

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.

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

2013-08-01

351

Neurotropic and neuroprotective activities of the earthworm peptide Lumbricusin.  

Science.gov (United States)

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 (NH2-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(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(Kip1) significantly blocked the antiapoptotic effect of Lumbricusin in 6-hydroxy dopamine-treated SH-SY5Y cells. These results suggest that promotion of p27(Kip1) degradation may be the main mechanism underlying the neuroprotective and neurotropic effects of Lumbricusin. PMID:24796676

Kim, Dae Hong; Lee, Ik Hwan; Nam, Seung Taek; Hong, Ji; Zhang, Peng; Hwang, Jae Sam; Seok, Heon; Choi, Hyemin; Lee, Dong Gun; Kim, Jae Il; Kim, Ho

2014-06-01

352

Split-sample comparison of directional and liquid nitrogen vapour freezing method on post-thaw semen quality in white rhinoceroses (Ceratotherium simum simum and Ceratotherium simum cottoni).  

Science.gov (United States)

To increase the quality of cryopreserved sperm in white rhinoceros, the liquid nitrogen vapour (LN vapour) freezing and the multi-thermal gradient directional freezing methods were compared. Sixteen white rhinoceros (Ceratotherium simum sp.) were electro-ejaculated. Semen samples were diluted with cryoextender (Tris, lactose, egg-yolk, DMSO) and aliquoted into straws for LN vapour freezing, and glass hollow tubes for directional freezing. The sperm quality was evaluated before and after freezing by assessing the following parameters: motility, morphologic state, acrosomal integrity and plasma membrane function and integrity (i.e. sperm viability) as defined by the hypo-osmotic swelling. Directional freezing improved the sperm viability by 5.6% (p40%) percentages of morphologically normal, directional freezing (DF) resulted in 31.4% less abnormal acrosomes for the low quality group as well as 18.7% increase in intact acrosomes and 10.9% increase in motility for the high quality group compared to LN vapour freezing (LN) (p<0.01, p<0.03, p<0.01, respectively). LN showed a significant reduction in sperm head volume (5.7%, p<0.05) compared to the prefreeze; whereas, no significant reduction in head volume was demonstrated after DF. Several additives (xanthenuric acid, cytochalasin D, potassium, EDTA) to the basic cryoextender provided no significant improvement in spermatozoal survival after directional freezing. In conclusion, directional freezing proved to facilitate higher gamete survival compared to LN vapour freezing. This is especially effective in ejaculates of low sperm quality and is important in endangered species where high quality semen donors are often not accessible. These results suggest that directional freezing could be valuable particularly for species with limited freezability of spermatozoa. PMID:18775559

Reid, C E; Hermes, R; Blottner, S; Goeritz, F; Wibbelt, G; Walzer, C; Bryant, B R; Portas, T J; Streich, W J; Hildebrandt, T B

2009-01-15

353

Effect of radiation and freezing on [3H]DNA of Yersinia enterocolitica.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Freezing of the enteropathogenic bacterium Yersinia enterocolitica to -18 and -75 degrees C caused 7 and 42% cell death, respectively, and 0.329 and 0.588 single-strand breaks per 10(8) daltons of DNA, respectively, while radiation to one D10 dose (10% cell survival) combined with freezing to 2 to 0, -18, and -75 degrees C induced 0.05, 0.75, and 5.04 single-strand breaks, respectively. The increase in the effectiveness of radiation with respect to the yield of single-strand breaks at -18 and...

Grecz, N.; El-zawahry, Y. A.

1984-01-01

354

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

Science.gov (United States)

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

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

2013-07-01

355

Inhibitory of Encapsulated Earthworm Extract (Lumbricus rubellus on Pathogenic Bacteria in Vitro  

Directory of Open Access Journals (Sweden)

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 ºC 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.

L. Istiqomah

2012-04-01

356

Space-time dynamics in situ of earthworm casts under temperate cultivated soils  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Soil does not always benefit from disturbance by earthworms. We investigated whether (under a temperate climate and in maize growing in rows running down-hill) earthworm casts could contribute to soil erosion and losses of nutrients in runoff water. Observations of casts were made in compacted (wheel-tracks) and non-compacted (untrafficked) inter-rows, for a 2-month period in spring. Estimates of surface-cast production in a temperate maize crop ranged between 2.5 to 3.2 kg (d.w soil) m?...

2009-01-01

357

Study of Genital Variations among the Earthworms of Genus Pheretima Inhabiting the Soil of Islamabad  

Directory of Open Access Journals (Sweden)

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

Ambreen Faiz

2004-01-01

358

Enzymatic Regulation of Glycogenolysis in a Subarctic Population of the Wood Frog: Implications for Extreme Freeze Tolerance  

Science.gov (United States)

The wood frog, Rana sylvatica, from Interior Alaska survives freezing at –16°C, a temperature 10–13°C below that tolerated by its southern conspecifics. We investigated the hepatic freezing response in this northern phenotype to determine if its profound freeze tolerance is associated with an enhanced glucosic cryoprotectant system. Alaskan frogs had a larger liver glycogen reserve that was mobilized faster during early freezing as compared to conspecifics from a cool-temperate region (southern Ohio, USA). In Alaskan frogs the rapid glucose production in the first hours of freezing was associated with a 7-fold increase in glycogen phosphorylase activity above unfrozen frog levels, and the activity of this enzyme was higher than that of frozen Ohioan frogs. Freezing of Ohioan frogs induced a more modest (4-fold) increase in glycogen phosphorylase activity above unfrozen frog values. Relative to the Ohioan frogs, Alaskan frogs maintained a higher total protein kinase A activity throughout an experimental freezing/thawing time course, and this may have potentiated glycogenolysis during early freezing. We found populational variation in the activity and protein level of protein kinase A which suggested that the Alaskan population had a more efficient form of this enzyme. Alaskan frogs modulated their glycogenolytic response by decreasing the activity of glycogen phosphorylase after cryoprotectant mobilization was well under way, thereby conserving their hepatic glycogen reserve. Ohioan frogs, however, sustained high glycogen phosphorylase activity until early thawing and consumed nearly all their liver glycogen. These unique hepatic responses of Alaskan R. sylvatica likely contribute to this phenotype’s exceptional freeze tolerance, which is necessary for their survival in a subarctic climate.

do Amaral, M. Clara F.; Lee, Richard E.; Costanzo, Jon P.

2013-01-01

359

Enzymatic regulation of glycogenolysis in a subarctic population of the wood frog: implications for extreme freeze tolerance.  

Science.gov (United States)

The wood frog, Rana sylvatica, from Interior Alaska survives freezing at -16°C, a temperature 10-13°C below that tolerated by its southern conspecifics. We investigated the hepatic freezing response in this northern phenotype to determine if its profound freeze tolerance is associated with an enhanced glucosic cryoprotectant system. Alaskan frogs had a larger liver glycogen reserve that was mobilized faster during early freezing as compared to conspecifics from a cool-temperate region (southern Ohio, USA). In Alaskan frogs the rapid glucose production in the first hours of freezing was associated with a 7-fold increase in glycogen phosphorylase activity above unfrozen frog levels, and the activity of this enzyme was higher than that of frozen Ohioan frogs. Freezing of Ohioan frogs induced a more modest (4-fold) increase in glycogen phosphorylase activity above unfrozen frog values. Relative to the Ohioan frogs, Alaskan frogs maintained a higher total protein kinase A activity throughout an experimental freezing/thawing time course, and this may have potentiated glycogenolysis during early freezing. We found populational variation in the activity and protein level of protein kinase A which suggested that the Alaskan population had a more efficient form of this enzyme. Alaskan frogs modulated their glycogenolytic response by decreasing the activity of glycogen phosphorylase after cryoprotectant mobilization was well under way, thereby conserving their hepatic glycogen reserve. Ohioan frogs, however, sustained high glycogen phosphorylase activity until early thawing and consumed nearly all their liver glycogen. These unique hepatic responses of Alaskan R. sylvatica likely contribute to this phenotype's exceptional freeze tolerance, which is necessary for their survival in a subarctic climate. PMID:24236105

do Amaral, M Clara F; Lee, Richard E; Costanzo, Jon P

2013-01-01

360

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

Directory of Open Access Journals (Sweden)

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.

Ea Kosman Anwar

2009-05-01

 
 
 
 
361

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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, so...

Nathanon Trachoo; Panomkorn Wechakama; Anuchita Moongngarm; Maitree Suttajit

2008-01-01

362

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 (0–5 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

2013-12-01

363

Comparison of the chemical alteration trajectory of Liriodendron tulipifera L. leaf litter among forests with different earthworm abundance  

Science.gov (United States)

To investigate the control of earthworm populations on leaf litter biopolymer decay dynamics, we analyzed the residues of Liriodendron tulipifera L. (tulip poplar) leaves after six months of decay, comparing open surface litter and litter bag experiments among forests with different native and invasive earthworm abundances. Six plots were established in successional tulip poplar forests where sites varied in earthworm density and biomass, roughly 4-10 fold, of nonnative lumbricid species. Analysis of residues by diffuse reflectance Fourier transform infrared spectroscopy and alkaline CuO extraction indicated that open decay in sites with abundant earthworms resulted in residues depleted in cuticular aliphatic and polysaccharide components and enriched in ether-linked lignin relative to open decay in low earthworm abundance plots. Decay within earthworm-excluding litter bags resulted in an increase in aliphatic components relative to initial amendment and similar chemical trajectory to low earthworm open decay experiments. All litter exhibited a decline in cinnamyl-based lignin and an increase in nitrogen content. The influence of earthworm density on the chemical trajectory of litter decay was primarily a manifestation of the physical separation and concentration of lignin-rich and cutin-poor petioles with additional changes promoted by either microorganisms and/or mesofauna resulting in nitrogen addition and polysaccharide loss. These results illustrate how projected increases in invasive earthworm activity in northern North American forests could alter the chemical composition of organic matter in litter residues and potentially organic matter reaching the soil which may result in shifts in the aromatic and aliphatic composition of soils in different systems.

Filley, Timothy R.; McCormick, Melissa K.; Crow, Susan E.; Szlavecz, Katalin; Whigham, Dennis F.; Johnston, Cliff T.; van den Heuvel, Ronald N.

2008-03-01

364

Real-time measurement of metabolic rate during freezing and thawing of the wood frog, Rana sylvatica: implications for overwinter energy use.  

Science.gov (United States)

Ectotherms overwintering in temperate ecosystems must survive low temperatures while conserving energy to fuel post-winter reproduction. Freeze-tolerant wood frogs, Rana sylvatica, have an active response to the initiation of ice formation that includes mobilising glucose from glycogen and circulating it around the body to act as a cryoprotectant. We used flow-through respirometry to measure CO(2) production ( ) in real time during cooling, freezing and thawing. CO(2) production increases sharply at three points during freeze-thaw: at +1°C during cooling prior to ice formation (total of 104±17 ?l CO(2) frog(-1) event(-1)), at the initiation of freezing (565±85 ?l CO(2) frog(-1) freezing event(-1)) and after the frog has thawed (564±75 ? l CO(2) frog(-1) freezing event(-1)). We interpret these increases in metabolic rate to represent the energetic costs of preparation for freezing, the response to freezing and the re-establishment of homeostasis and repair of damage after thawing, respectively. We assumed that frogs metabolise lipid when unfrozen and that carbohydrate fuels metabolism during cooling, freezing and thawing, and when frozen. We then used microclimate temperature data to predict overwinter energetics of wood frogs. Based on the freezing and melting points we measured, frogs in the field were predicted to experience as many as 23 freeze-thaw cycles in the winter of our microclimate recordings. Overwinter carbohydrate consumption appears to be driven by the frequency of freeze-thaw events, and changes in overwinter climate that affect the frequency of freeze-thaw will influence carbohydrate consumption, but changes that affect mean temperatures and the frequency of winter warm spells will modify lipid consumption. PMID:23255194

Sinclair, Bremxnt J; Stinziano, Joseph R; Williams, Caroline M; Macmillan, Heath A; Marshall, Katie E; Storey, Kenneth B

2013-01-15

365

Exploring the Nature of Contact Freezing  

Science.gov (United States)

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.

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

2012-12-01

366

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

Earthworms emit nitrous oxide (N2O) and dinitrogen (N2). It has been hypothesized that the in situ conditions of the earthworm gut activates ingested soil denitrifiers during gut passage and leads to these in vivo emissions (M. A. Horn, A. Schramm, and H. L. Drake, Appl. Environ. Microbiol. 69:1662-1669, 2003). This hypothesis implies that the denitrifiers in the earthworm gut are not endemic to the gut but rather are regular members of the soil denitrifier population. To test this hypothesis...

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

2006-01-01

367

Nitrous oxide reductase genes (nosZ) of denitrifying populations in soil and the earthworm gut are phylogenetically similar  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Earthworms emit nitrous oxide (N2O) and dinitrogen (N2). It has been hypothesized that the in situ conditions of the earthworm gut activates ingested soil denitrifiers during gut passage and leads to these in vivo emissions (M. A. Horn, A. Schramm, and H. L. Drake, Appl. Environ. Microbiol. 69:1662-1669, 2003). This hypothesis implies that the denitrifiers in the earthworm gut are not endemic to the gut but rather are regular members of the soil denitrifier population. To test this hypothesis...

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

2006-01-01

368

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

Science.gov (United States)

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.

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

2011-12-01

369

Freeze Denaturation of Fish Muscle Proteins  

Science.gov (United States)

Studies on the freeze denaturation of fish muscle proteins were reviewed with emphasis given to changes in their physicochemical and biochemical properties during frozen storage. Denaturation of actomyosin commonly occurs during frozen storage and side-to-side aggregation of myosin molecules apppears to major role in this reaction. The author's group performed freezing studies with isolated preparations of proteins from carp muscle, namely actomyosin, myosin, H-meromyosin, L-meromyosin, and actin. Freeze denaturation occurred with indvidual proteins as well as with their subunits. Not only aggregation but also some conformational changes were observed. Denaturation was inhibited in the presence of added glutamate.

Tsuchiya, Takahide

370

An efficient deep freeze tunnel; Zuinige diepvriestunnel  

Energy Technology Data Exchange (ETDEWEB)

The freezing of vegetables requires cooling to far below the zero point (-18 to -20{sup o}C). As a result, the energy consumption and the energy expenses of freeze tunnels are high. Accurate adjustment of the operational parameters of the freeze tunnel can result in up to 20% energy savings. A brief overview is given of the VITO study on the most important parameters that influence the energy consumption and the energy saving options at `Stevens Koeltechniek` and `Compufreez` in Ieper, Belgium. 2 ills.

Van Bael, J. [Vlaamse Instelling voor Technologisch Onderzoek VITO, Mol (Belgium)

1997-11-01

371

Molten salt freeze seal. Final report  

Energy Technology Data Exchange (ETDEWEB)

This report documents the results of the testing performed at Sandia National Laboratory, Albuquerque, New Mexico, on the applicability of a sodium freeze seal type valve stem in a molten salt environment. The freeze seal tests consisted of cycling the valve stem at set temperature intervals, checking the temperature distribution for freeze plug location, and verifying the actuator forces. In addition to the test results, this report also documents the engineering analysis and other tasks performed before testing to form a basis for predicted test conditions and recommendations for the test program.

Corugedo, J.J.

1985-08-01

372

A wash solution for freezing wells  

Energy Technology Data Exchange (ETDEWEB)

The use is proposed of a wash solution which contains 5 to 95 percent aliphatic alcohols and 5 to 95 percent bentonite for deepening shafts in difficult mining and geological conditions using an artificial freezing method. The volume of bentonite contained in the wash solution is a function of the mining and geological conditions in which the shaft is being driven. The use of aliphatic alcohols prevents or substantially reduces freezing of the rock mass to the external surface of the freezing pipes. In the cited examples the composition of the solutions is: 93 percent butyl alcohol and 7 percent bentonite and 30 percent butyl alcohol and 70 percent bentonite.

Machowski, M.; Okrajny, S.; Stopka, Z.

1982-10-30