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Earthworms and Sphingobacterium sp. are known for their strong organic compound decomposition ability and wide distribution in soil. However, interactions of soil organic matter decomposition with soil properties and whether microbial species such as Sphingobacterium sp. could assist earthworms in carbon and nitrogen transformation in soil remain poorly understood. Earthworms (Eisenia fetida , Amynthas gracilis) and Sphingobacterium sp. were introduced in non-contaminated and cadmium-contaminated soils under controlled laboratory conditions for 20 days. We examined their individual or combined effects on carbon and nitrogen forms and related enzyme activities to assess their influence on soil C and N cycling. Individual Sphingobacterium sp. inoculation led to significantly decreased organic carbon (SOC) contents, reducing it by 16.5% in non-contaminated soil and by 3.77%, in Cd-contaminated soil. It resulted in an increased microbial biomass carbon (MBC) contents, reaching 1685 ± 292 mg·kg−1 in non-contaminated soil. Individual introductions of E. fetida and A. gracilis caused a decline in SOC content in non-contaminated soil, but increased significantly dissolved organic carbon (DOC) and alkali-hydrolysable nitrogen (AN) contents by 75.8%, 53.6% and 32.9%, 20.9%, respectively. In contrast, in Cd-contaminated soil, only the significant combined effects of earthworms and Sphingobacterium sp. were linked to significant increase in SOC contents, raising by 7.22% and 9.64% in E. fetida + Sphingobacterium sp. and A. gracilis + Sphingobacterium sp. treatments, respectively. In non-contaminate soil, the combined effects of earthworm and Sphingobacterium sp. further increased DOC and AN content by 212%, 134% and 31.3%, 25.4% in the treatments of E. fetida + Sphingobacterium sp. and A. gracilis + Sphingobacterium sp., respectively; the highest ratios of DOC to SOC and AN to total Nitrogen (TN) were found in the earthworm + Sphingobacterium sp. treatments as well. In non-contaminated soil, Sphingobacterium sp. and earthworms mainly influenced β-glucosidase (BG), urease (URE), N-acetyl-β- d -glucosaminidase (NAG) activities and fluorescein diacetate hydrolysis (FDA) hydrolysis, while in Cd-contaminated soil, they mainly influenced invertase (INV), NAG, URE, and protease (PRO) activities. Principal component analysis indicated that in non-contaminated soil, the earthworm activities dominated the mineralization processes of soil carbon and nitrogen, and Sphingobacterium sp. can intensify this process when it was inoculated in soil along with earthworms. Furthermore, both earthworm species increased C and N levels by elevated INV and PRO activities in combined inoculation. However, in contaminated soil, the impact of earthworm inoculation on soil C stabilization showed a species dependent pattern. E. fetida reduced C mineralization by decreasing URE activities, while A. gracilis enhanced C stabilization by increasing INV activities and decreasing PRO activities. In conclusion, earthworms played a key role in enhancing C and N mineralization in non-contaminated soil and promoting C stabilization in contaminated soil. Both earthworm species followed similar strategies in the former process but adopted different strategies in the latter. When introduced individually, Sphingobacterium sp. was able to promote mineralization in both soils, primarily assisting earthworms in improving carbon and nitrogen mineralization in non-contaminated soil but hindering these processes in Cd-contaminated soil. These findings provide insights into the combined effects of earthworms and microorganisms on carbon and nitrogen cycling. • Sphingobacterium sp. could promote C mineralization in both soils. • Earthworms facilitated C and N mineralization in non-contaminated soil. • Earthworms enhanced C stabilization in Cd-contaminated soil. • Sphingobacterium sp. could assist earthworms in improving C and N mineralization in non-contaminated soil. • Earthworm activities dominated the C and N turnover in this strain-earthworm-soil system. [ABSTRACT FROM AUTHOR]

Alley cropping is the combination of tree rows and crop alleys. The tree row is covered by an understory vegetation strip (UVS), providing a beneficial habitat for many soil fauna, which could disperse through spillover to the crop alleys. However, such movements have never been directly studied. Our experiment investigated earthworm fluxes in the tree row vicinity using a trap technique, in a Mediterranean agroforestry alley cropping field cultivated with peas and planted with walnut trees. We assessed earthworm density at different distances from the UVS (0 m, 0.3 m, 1 m and 6 m) by hand sorting soil monoliths (25*25*30 cm) in spring 2019, at the start and the end of a two-month experiment. During this period, we detected earthworm fluxes by placing directional traps at 30 cm from the UVS border. Traps consisted of three glued plastic walls placed vertically in the soil. They delimited a soil block of 25*25 cm by 20 cm depth and were open on one side. More epigeic earthworms were found in the UVS and up to 30 cm from the UVS border than in the middle of the crop alley. By contrast, the earthworm Allolobophora chlorotica presented a homogeneous distribution in the plot. Trapped earthworms were mostly of the All. chlorotica species, and 1.6 times more earthworms were found in traps open towards the crop alley than in traps open towards the UVS. These results suggest that in spring, earthworms are moving more from the crop alley towards the UVS than in the other direction, probably using the tree row and its vicinity as a refuge against adverse summer conditions in the crop alley. [Display omitted] • We designed a trapping technique to capture earthworms moving through the soil. • Tree rows did not act as a source of earthworms to the nearby crop alleys in spring. • Earthworm fluxes probably depend on species and seasons. [ABSTRACT FROM AUTHOR]

The addition of composted green waste (CGW) into soil-forming materials during land reclamation can benefit tree growth by improvement of soil properties and provide an effective waste management solution. CGW addition may also assist the establishment of earthworm populations, which in turn aid soil development through their burrowing and feeding activities. An experiment was set up on a reclaimed landfill site, to measure the effects of CGW addition on soil physical and chemical quality and subsequently on the survival and growth of two tree species ( Acer platanoides and Alnus cordata ). A further objective was to measure the influence of earthworm ( Aporrectodea longa ) addition on the above. CGW addition led to significantly greater A. cordata growth (height and diameter) and increased survival rate. No benefits from CGW addition were observed on A. platanoides growth or survival, although this is likely due to soil drought conditions during establishment. CGW addition significantly increased levels of organic carbon and essential plant macro-nutrients in the reclaimed soil. Soil pH rose slightly across all treatments, with highest final pH under the control treatment. Earthworm inoculation, as used, was unsuccessful at increasing population density of A. longa . This experiment showed that CGW application can effectively improve tree establishment and soil quality on reclaimed landfill; however tree species selection is an important consideration, based on individual species tolerance and sensitivity to certain soil conditions. These findings will be informative to decisions on soil amendment and afforestation activities on similar reclaimed landfill sites. [ABSTRACT FROM AUTHOR]

Mitochondrial cytochrome oxidase subunit I (COI) and 16S rRNA gene sequence data were analysed for 43 specimens of Drawida ghilarovi – earthworms of a tropical genus on the northern boundary of their natural habitat, including two ecological forms and three colour morphs collected from different regions of the southern Russian Far East. Intraspecific genetic differentiation of these clitellata was analysed with different criteria that characterise different forms and morphs. A sample of anecic worms was shown to possess higher genetic variation than a sample of epigeic worms. Haplotype network reconstructions showed that the meadow-swamp epigeic black-coloured D. ghilarovi is more highly diverged from the anecic forest grey- and brown-coloured worms than the grey and brown colour morphs are from each other. Genetic differentiation between three colour morphs ranged from 9.89 ± 0.58 to 11 ± 0.59% using COI and 16S data. An AMOVA test and an exact test showed a high probability of non-differentiation between grey and brown earthworms. A multimodal mismatch distribution was revealed for the whole D. ghilarovi sample and for each colour morph. The minimum spanning tree showed that the differentiation of specimens is associated with ecological and geographical criteria. Molecular data for Drawida showed high genetic differentiation between epigeic and anecic using COI and 16S gene sequence data as well as the various phylogenetic relationships among the studied forms. The anecic earthworms possibly represent different genetic lineages of the D. ghilarovi species complex. The epigeic Drawida , based on the complex data, can be considered a new species of this genus. [ABSTRACT FROM AUTHOR]

Due to the influence of Atlantic Ocean and Mediterranean Sea, Spain has different climates, from desert to Atlantic. We sampled the parthenogenetic earthworm Eiseniella tetraedra in two different biogeographical zones in Spain, in order to study their genetic diversity and test their potential distinctiveness. Moreover, we evaluated the presence or absence of two different lineages (Eurosiberian and Mediterranean) found in other parthenogenetic earthworms such as Aporrectodea trapezoides and A. rosea . We studied the molecular markers COI, 16S and 28S. E. tetraedra presents a high diversity in Spain (one COI haplotype every two individuals were found) and no clear geographical patterns except for diffuse patterns along the Guadarrama River basin. In contrast, worldwide localities were more homogeneous with low diversity, to be confirmed with further samples. After morphological study, no correlation was found between phylogenetic relationships and the diagnostic characters for the previously described subspecies in E. tetraedra . [ABSTRACT FROM AUTHOR]

Post-industrial sites across Europe may have developed over periods in excess of a century, often leading to poor nutrient soils with noxious constituents and extreme pH values. One such site, Nob End (Bolton, UK), a toxic tip created in the 1800s from a sodium carbonate factory, represents an “island of alkalinity in an acidic sea” where the weathering process (from pH 12) has provided a suitable environment for a rich alkali-loving flora and hence, deserving its designation as a Site of Special Scientific Interest. Despite their importance, the belowground communities have not been investigated and for this reason, in this study, we explored how soil macro- and mesofauna communities respond to extreme pH values in a system that has also experienced recent changes in management practices. As expected, earthworms, mites, insects and woodlice numbers were significantly higher and the community diversity enriched at the (now pH 8) alkaline sites, whereas in areas where acidic boiler waste was historically deposited, enchytraeids, collembolans and dipteran larvae populations dominated the soil communities. Surprisingly, site management (cutting back of scrub) in the alkaline soil areas had a significant positive effect on soil macro-fauna by promoting numbers and biomass, but severely reduced the microarthropod populations. A transect investigation across an increasing pH gradient (from 4.5 to 8.0) was mirrored by a rise in earthworm numbers and species richness. Earthworms were further investigated surrounding the site, seeking potential sources of colonisation, with the majority of species at Nob End also present in adjacent non-industrially-influenced areas. This work demonstrates that soil fauna can ultimately colonise extreme edaphic conditions and these extreme environments have not prompted the development of specific faunal communities. As management of above-ground communities significantly influenced soil invertebrate communities, this could represent an important restoration practice to improve soil structure and fertility at this polluted site. [ABSTRACT FROM AUTHOR]

Gut-stimulated denitrifiers are responsible for the in vivo emission of N 2 O by earthworms, and contribute to the N 2 O that is emitted from certain terrestrial ecosystems. To evaluate the separate effect of gut-stimulated denitrifiers on N 2 O emissions, earthworms or their casts were inoculated into sterilized and unsterilized soil, respectively, and compared with control (soil without inoculation) in this study, to find out if there was a difference in N 2 O emissions during the 15 days incubation period. Compared with the control, earthworm inoculation significantly increased N 2 O flux and relative densities of nirS and narG gene copy numbers both in sterilized and unsterilized soil, while no significant difference was found when we transited and recolonized those gut-stimulated denitrifiers into soil artificially. In contrast, cast inoculation did not change CO 2 emission in the unsterilized soil, but significant increased cumulative CO 2 emission in the sterilized soil. Our data suggest that the effect of gut-stimulated denitrifiers on soil N 2 O produce was strongly diminished when separated from earthworm activity. [ABSTRACT FROM AUTHOR]

The negative impacts (allelopathic effects) of phenolic compounds (PCs) in soil on plant growth and microbial communities have recently received considerable attention. Similarly, there have been several recent studies on the effects of microbes on the degradation of PCs. Because of the profound effects of their feeding and burrowing activity, earthworms should have significant effects on PCs degradation; however, few studies have examined this potential effect, and particularly, factors that may affect the course of degradation. We tested different earthworm species and density, different conditions (sterilization or not) of mixture of soil and plant residual, and different source of PCs to evaluate the capacity of earthworms to accelerate PCs degradation. In addition, earthworm behavior experiments were set up to test whether adding plant leaves can stimulate earthworm feeding activity. The results showed that native earthworms exhibited a higher capacity than compost earthworms for degrading PCs; furthermore, when the number of Metaphire guillemi reached 300 individuals m −2 in our experimental units, the PCs decreased most quickly, and the residual PCs concentration was 105 μg ( p -coumaric acid)g −1 (dry soil) less than that of control group. The source of PCs also affected their degradation rate, as PCs derived from leaves seemed to degrade more quickly. The results of our experiment suggested that earthworms avoid feeding on phenolic acids, but can be induced to do so by adding leaves to the substrate. These results indicate that earthworm activity can accelerate the degradation of total PCs, and that this may be further facilitated by incorporation of organic matter, which may be used to alleviate allelopathic effects of PCs in soil. [ABSTRACT FROM AUTHOR]

Earthworms may influence soil N 2 O emissions by stimulating free-living denitrifiers due to the restructuring of the soil environment, and by inoculating gut-stimulated denitrifying bacteria during the excretion process. However, the relative importance of each effect on soil N 2 O emissions is still not clear. To determine the differences in earthworm ( Eisenia fetida )-induced N 2 O emissions, sterilized (from which the impacts of indigenous soil microbes are limited) and unsterilized soils were used in the 30-days microcosm experiment. Earthworm inoculation improved soil ammonium ( N H 4 + –N ) , nitrate ( N O 3 − –N ) and dissolved organic carbon (DOC) concentrations in both soils. Soil N 2 O emission also increased with the addition of earthworms, but the significant difference on cumulative N 2 O emissions were only detected in the sterilized soil (362.22 and 645.86 μg N 2 O–N kg −1 dry soil with and without earthworm inoculation, respectively). Redundancy analysis indicated that the earthworm inoculation changed the soil microbial community structure in both soils. The relative density of nirS genes was significantly increased due to earthworm inoculation in sterilized soil, but no obvious difference was detected in the unsterilized soil. In conclusion, by changing the soil bacterial community via gut-stimulated denitrifiers, earthworms may increase N 2 O emissions in the sterilized soil, while this effect may be diminished by competition with indigenous soil microorganisms in unsterilized soil. [ABSTRACT FROM AUTHOR]

The endemic earthworm Drawida ghilarovi Gates 1969, which is found in the Primorye and the south of the Khabarovsk Krai, is represented in the forest by a live form of aneciques (burrowing) and in the wetland by soil-litter (epigeic) worms. These moniligastrida species noticeably differ both in pigmentation (grey and black forms, respectively) and in ecology specifics. Molecular analysis of these specimens has been performed using partial sequences of the mitochondrial COI and 16S genes. The genetic p-distances between the two colored forms of D. ghilarovi and within the black form of this species have been estimated and the phylogenetic relationships of these different forms reconstructed using the maximum parsimony and maximum likelihood algorithms. Genetic differentiation within the genus Drawida ranged from 16.3 to 23% when using the COI gene sequence data. Genetic differences between the colored forms of D. ghilarovi were 14.8–16.9%, suggesting species level differentiation between these forms. Phylogenetic relationships, based on the combined molecular data, showed obvious differentiation between the grey and black forms of D. ghilarovi . In addition, there was also considerable differentiation between different samples of the D. ghilarovi black forms, collected from different geographical locations. [ABSTRACT FROM AUTHOR]

Earlier studies of post-mining soils near Sokolov, Czech Republic, showed that colonization of the spoil heaps by earthworms greatly changes the plant community composition and soil characteristics. The current study determined how colonization of heaps by the endogeic earthworm Aporrectodea caliginosa is affected by the vegetation, litter, and soil at sites of different ages. In one experiment, we measured the performance of A . caliginosa in 25-l microplots at four heaps of increasing age and successional stage (8, 15, 25, and 48 years). After 6 months, A. caliginosa number and biomass in microplots decreased in young heaps (8 and 15 years old), remained constant in the 25-year-old heap, and increased in the 48-year-old heap. In other words, A. caliginosa survival, growth, and reproduction increased with successional stage. In a second field experiment, we tested A . caliginosa performance in microplots containing different types of litter at two heaps at mid-successional stages (19 and 25 years old). After 12 months, A. caliginosa biomass and abundance were greater with grass litter than with shrub and tree litter, but were greater in the 25-year-old heap, which was dominated by shrubs, than in the 19-year-old heap, which was dominated by grasses. Together, the two experiments indicate that colonization of heaps by A. caliginosa is enhanced by succession and by remaining patches of early successional vegetation in heaps at mid-successional stages. [ABSTRACT FROM AUTHOR]

The common epigeic earthworm Lumbricus rubellus has been found to comprise two genetically distinct lineages and this genetic heterogeneity could compromise its currently widespread use as a sentinel in soil ecotoxicology. An extensive analysis of lineage diversity was conducted on UK populations of L. rubellus, comprising 137 individuals collected from England and Wales. Sequencing of the mitochondrial COI region revealed the widespread occurrence of the two described lineages throughout Britain, which were often found to co-exist at the same site. Morphological characters were investigated to differentiate the two lineages. A rapid genetic test (mitochondrial PCR amplification and restriction digestion) was applied to determine the lineage of each specimen. A blind trial revealed a characteristic glandular tumescence to be effective in differentiating the lineages, particularly in identifying 'lineage B' worms. COI sequence analysis was also conducted upon three other Lumbricus species, which failed to uncover any genetic lineages comparable to those found within L. rubellus. [ABSTRACT FROM AUTHOR]

In Northern Vietnam, organic fertilization programmes are being tested to restore soil fertility and reduce soil erosion. However, the amendment of organic matter in soil is also associated with the development of the invasive earthworm species Dichogaster bolaui. The objective of this study was to investigate the influence of organic matter amendment quality (compost vs. vermicompost) on D. bolaui. Our study confirmed D. bolaui development in organic patches in the field. However, we also observed that the flat-backed millipede Asiomorpha coarctata proliferated in these organic patches. Native to Asia, this millipede species is also considered as invasive in America. Both D. bolaui and A. coarctata more rapidly colonized compost than vermicompost patches. A laboratory experiment confirmed this trend and showed the limited development of D. bolaui in vermicompost. This is probably because of the decreased palatability of this substrate to soil fauna. In conclusion, any restoration practice that aims to increase the organic stocks in soils degraded by erosion should consider the quality of the organic amendment. In Northern Vietnam, vermicompost may be the preferred substrate for restoring soils while limiting the spread of D. bolaui. [ABSTRACT FROM AUTHOR]

Abstract: To assess the toxic effects of three pesticides on non-target organism, we exposed the earthworm Eisenia fetida (Savigny 1826) to artificial soil supplemented with different concentrations of the examined pesticides based on the recommended agricultural doses (RAD). Their commercial formulations are: Galition G-5 (insecticide: active ingredient, a.i., malathion and fenitrothion), Terbis (herbicide: a.i. terbuthylazine), and Gardene (limacide: a.i. metaldehyde). The laboratory test was conducted according to the OECD guidelines. Mortality, biomass, and growth inhibition were chosen as toxic endpoints. No death was recorded at the lowest concentration (1/4 RAD) of the insecticide or the limacide after 7- and 14-day exposures, nor was it recorded at the highest concentration (4× RAD) of the insecticide or the limacide after 7-day exposure. Triazine herbicide Terbis was found the most toxic and ecologically dangerous to E. fetida, because it LC50 value (1.26 mg kg−1) was very close to the respective RAD and the growth inhibition in all concentrations was significantly positive. Although E. fetida was found susceptible to the organophosphorus insecticide Galition, due to the significant positive growth inhibition at the highest concentration, the value of LC50 was higher than its RAD. On the other hand, metaldehyde limacide Gardena was found ecologically safe because the LC50 value was higher than its RAD and weight was not significantly changed. [Copyright &y& Elsevier]

Abstract: Anecic earthworms have the ability to incorporate carbon (C) from the surface to depth in the soil. This study aimed to quantify the rate of spread of Aporrectodea longa, and their influence on the amount of C stored, in two contrasting soils where this earthworm was introduced in the 1980s. The rate of spread of A. longa at both sites (5.3–12.5 m/y) is similar to endogeic species. Over several decades there was a decrease in soil C in the presence of A. longa in the Pallic soil (78 912 vs. 85 796 kg C/ha for 0–300 mm) while soil C tended to increase in the Allophanic soil (141 845 vs. 111 076 kg C/ha at 0–300 mm). In the Pallic soil, bulk density tended to be lower in the presence of anecic earthworms at 150–300 mm depths and may have encouraged the decomposition of more stable C. Further, the interaction with higher abundances of endogeic earthworms and lower organic matter inputs in the Pallic soil than the Allophanic soil may help explain the lower soil C in the Pallic soil. The conflicting results in the two soils highlight the influence of the earthworm community and soil properties on C dynamics. [Copyright &y& Elsevier]

Abstract: The effects of chemical and manual weed management on the abundance of earthworms and composition of earthworm populations in a banana plantation were studied in a long term field experiment. Earthworm populations were monitored in plots receiving either a cyclical course of two applications of paraquat (480 mL ha−1) at monthly intervals followed by one of glyphosate (1680 mL ha−1) or manual weeding using slashing, mechanical cutting and scraping. There were no significant differences in earthworm counts between manual and chemical plots both in areas with 15% (15° inclination) site (F = 0.48, P = 0.49) and 25% (25° inclination) site (F = 0.44, P = 0.51) during the 2-year period. Instead, variation in earthworm counts could be attributed to differences in rainfall, organic matter, organic mulch and soil cover. [Copyright &y& Elsevier]

Abstract: The largest breeding colony of Manx shearwaters (Puffinus puffinus) in the world is found on the Isle of Rum in the inner Hebrides of Scotland. We collected a feather, guano, soil, vegetation, and earthworms near shearwater burrows to determine whether inputs of nitrogen (N) from guano were incorporated into belowground foodwebs. For comparison, similar samples were collected from a nearby plot that was experimentally fertilised 40 years prior. The shearwater feather had the highest level of 15N enrichment (+18‰), followed by guano (+12‰). Soil (+7.5‰) and vegetation (+5.7‰) collected at the burrow entrance were enriched with 15N relative to those collected at 2 m or more away (+0.5 to +3.1‰ for soil, and −2.5 to −4.6‰ for vegetation). In contrast, soil inside the fertilised plot had δ15N ≈ 0, but was enriched with 15N away from the plot edge. Earthworms collected from shearwater greens had enriched 15N signatures relative to earthworms from the fertilised plot (+3.8 and −0.9‰, respectively). Our data suggest that available N is tightly cycled in vegetation and soil for decades, and that shearwater derived N is substantially assimilated by earthworms. Therefore, because earthworms do not occur outside areas of shearwater influence, the birds should be viewed as ecosystem engineers of soil invertebrate foodwebs on Rum. [Copyright &y& Elsevier]

Abstract: Parthenogenesis has been known in a variety of animal taxa and is commonly found in oligochaetes. Many pheretimoid earthworms in Megascolecidae have been known to be or suspected to be parthenogenetic, but there has not been any genetic investigation on them. Amynthas catenus and Amynthas hohuanmontis are earthworms belonging to the Pheretima complex of the family Megascolecidae. Both are endemic to Mt. Hohuan at an elevation of about 3000 m in central Taiwan, and both have spermathecae from three pairs in segments VI–VIII (sexthecal) to absence (athecal) and reproductive organs in different degrees of degeneration. Here we present the genetic evidence revealed by amplified fragment length polymorphism (AFLP) markers to confirm the parthenogenetic mode of reproduction in A. catenus and A. hohuanmontis. Sixty-two selective primer combinations were used to generate a total of 4593 and 4812 bands for A. catenus and A. hohuanmontis, respectively. We found that the two earthworms are automictic (meiotic) parthenogens with offsprings showing slightly reduced number of AFLP markers compared with their parents. There was no sperm in any of the spermathecae examined. Selection and reproductive success among different genotypes of the two earthworms will be an important topic for future investigation. [Copyright &y& Elsevier]

Abstract: Earthworms contribute to the functioning and stability of soil processes which are equally fundamental to both forestry and agriculture. Earthworms are generally exposed to chemicals present in their terrestrial environment and have been used for assessing the chemical environmental pollution. Reliable and efficient extraction methods are required for studies of earthworms. However, when ecotoxicological and biomonitoring studies are conducted, besides the efficacy, it is also important that the extraction method does not influence the physiological status of the earthworms. Allyl isothiocyanate (AITC) application and the electrical octet method are non-destructive alternative extraction methods. The focus of this research was to investigate effects of electroshocking and AITC on molecular biomarkers in earthworms, since there is no data about possible side effects of these methods on physiological status of earthworms. Therefore, an experimental study was conducted using the earthworm species Eisenia andrei earthworms and the activities of acetylcholinesterase (AChE), catalase (CAT) and efflux pump were measured. Measurements showed that exposure to AITC on filter paper and direct application of electricity significantly affected measured biomarkers. Electroshocking caused decrease in AChE activity, whereas AITC caused decrease of AChE activity, as well as increase of CAT activity and increase in efflux pump activity. The obtained results demonstrate that these extraction methods could influence the physiological status of earthworms and therefore are unsuitable for ecotoxicological research and biomonitoring studies when sampled earthworms are used for biomarker measurements. [Copyright &y& Elsevier]

Abstract: The family Lumbricidae accounts for the most abundant earthworms in grasslands and agricultural ecosystems in the Paleartic region. Therefore, they are commonly used as model organisms in studies of soil ecology, biodiversity, biogeography, evolution, conservation, soil contamination and ecotoxicology. Despite their biological and economic importance, the taxonomic status and evolutionary relationships of several Lumbricidae genera are still under discussion. Previous studies have shown that cytochrome c oxidase I (COI) barcode phylogenies are informative at the intrageneric level. Here we generated 19 new COI barcodes for selected Aporrectodea specimens in Pérez-Losada et al. including nine species and 17 populations, and combined them with all the COI sequences available in Genbank and Briones et al. for Lumbricidae (435 sequences) and seven other Lumbricina families (480 sequences). Our maximum likelihood and Bayesian trees indicate that the genera Aporrectodea, Allolobophora, Eisenia and Dendrobaena (Lumbricidae) and Diplocardia, Metaphire and Amynthas (Megascolecidae) are polyphyletic and so invalid as currently defined. Our results also confirm that COI barcodes are a good proxy for estimating intrageneric phylogenetic diversity and relationships in earthworms. [Copyright &y& Elsevier]

Abstract: Exotic earthworms have previously been recorded in the UK. Many of those records are from the Royal Botanical Gardens, Kew. Earthworms were collected from Kew on two separate occasions in 2007 (March and August). In total 6 species were found, of which two are new species records for the British Isles. When updating the British earthworm species list it became apparent that many species are not inhabitants of UK soils but are transitory visitors in greenhouses. Their status in soils is currently unknown. A new system of recording earthworm species in the British Isles is proposed and consists of two parts. Part 1 lists those species found living freely in soils, part 2 lists those species whose status is unknown, many of which are likely to be imported visitors found in greenhouses. The need for systematic sampling of earthworms throughout the UK is highlighted and the possible effects of climatic change on earthworm populations are commented on. [Copyright &y& Elsevier]

Abstract: To clarify the historical phylogeography of a Japanese earthworm, nucleotide sequence variations of Metaphaire sieboldi were investigated with respect to its geographic distribution. Sequencing of mitochondrial DNA (mtDNA), including the cytochrome oxidase subunit I (COI) region and the 16S rDNA region, of 72 samples including 4 outgroup taxa, and phylogenetic analyses using neighbour-joining (NJ) and Bayesian inference (BI) methods indicated that M. sieboldi forms a monophyletic group. This monophyletic group was divided into seven subgroups; most subgroups comprised individuals from several areas, except for southern Shikoku and southern Kyushu. The phylogenetic tree demonstrated that the Shikoku and Kinki populations were paraphyletic at the basal node, and individuals from Kyushu and western Shikoku were positioned at the advanced group. Estimated phylogeographic events based on mtDNA analyses include (1) M. sieboldi originated in Shikoku and/or Kinki, (2) individuals from Chugoku and Kyushu have a common ancestor from Shikoku, and (3) individuals from western Shikoku originated from Kyushu progenitors (about 0.4–0.5mya) after separation by rising sea levels. [Copyright &y& Elsevier]

Abstract: Mining activities can cause severe soil pollution in mining area and its surroundings. Nevertheless, very little is known about the local environmental risk after the mining activities are ended in China. Earthworms and soil microbial biomass carbon (SMBC), which are often used as bioindicators of soil pollution, were studied in order to support chemical analyses in assessing the status of soil heavy metal pollution around an abandoned copper mine in eastern Nanjing, China. Seven earthworm species belonging to three families (Megascolecidae, Moniligastridae, and Lumbricidae) were present. Correlations between earthworm densities or biomass and a range of soil physical and chemical parameters were generally poor; however, several linear regression models based on the soil physicochemical characteristics and metal concentrations in earthworm bodies were established for each metal (Cu, Cd, and Zn) and each earthworm family. Therefore, metal bioaccumulation by soil-dwelling earthworms can be used as an ecological indicator of metal availability for this area. The SMBC, which varied from 83.9 to 499gkg−1, did not correlate with the soil heavy metal concentrations, and SMBC is not proposed as a sensitive indicator for evaluating the environmental effects of soil heavy metal pollution in this area. [Copyright &y& Elsevier]

Abstract: In an attempt to isolate gonad-related genes from the earthworm Eisenia fetida (Savigny, 1826), we have isolated two genes with sequence similarities to mammalian valosine-containing proteins (evcp-1 and evcp-2) [T. Suzuki, M. Honda, S. Matsumoto, S.R. Stürzenbaum, S. Gamou. Valosine-containing proteins (VCP) in an annelid: identification of a novel spermatogenesis related factor, Gene 362 (2005) 11–18]. To understand the origin of the earthworm vcp genes, and to provide tools for further detailed genetic and physiological analyses, a Bacterial Artificial Chromosome (BAC) library was established, and the clones carrying the entire evcp-1 and evcp-2 genes were isolated. Genomic sequencing revealed that evcp-1 and evcp-2 occupied approximately 16kb and 18kb, respectively, and consisted of 14 introns and 15 exons, a number that is similar to mammalian VCPs. [Copyright &y& Elsevier]

Abstract: More than 50 parameters of vegetation, soil and soil fauna were studied in 27 non-reclaimed post mining sites of various age (1–41years old) located near the town of Sokolov (Czech Republic). A clay alkaline substrate (pH 8.5) was dumped in heaps; its pH and contents of available calcium and sodium decreased during succession. Total carbon and nitrogen, available potassium and water-soluble phosphorus increased with increasing successional age. In early stages, i.e. before the establishment of a shrub layer, the topsoil was formed mainly from the dumped spoil material. In shrub-dominated sites (14–22years old), the litter reserve on the soil surface was higher than annual litter production, and a thick fermentation layer developed below the litter layer indicating slow litter decomposition and soil mixing. In older plots (24year old or older), a humus layer was formed and the thickness of the fermentation layer decreased. Microstructure analysis indicated that earthworm activity, namely the mixing of organic and mineral layers, played a principal role in humus layer formation. No group of soil fauna preferred early successional stages, but tardigrades, bacteriophagous and fungivorous nematodes, and microsaprophagous dipterans, were tolerant to these stages. The density of most fauna guilds increased in intermediate stages with thick fermentation layer. Pauropods and testate amoebae reached highest densities on these sites. Macrosaprophagous guilds of soil fauna, most important for litter decomposition and soil mixing, attained their highest density in the oldest sites. Two clearly separated clusters of sites were distinguished based on TWINSPAN classification of vegetation. The first cluster included sites 1–23years old, dominated by ruderal plants. Sites 24–41years old were grouped in the second cluster; forest and grassland species were more frequent here. The presence of humus layer was selected by a discriminant analysis as the strongest predictor to discriminate between these two clusters. All considered ecosystem components, i.e. soil, soil fauna, and vegetation, passed through substantial changes in about the 25thyear of succession and their changes were mutually correlated. [Copyright &y& Elsevier]

Abstract: A novel experiment design based on the axial simplex design was used to study the effects of earthworm functional diversity on microbial biomass and microbial community level physiological profiles in soils. This mesocosm experiment was carried out at two densities of earthworm and at two levels of food supply. Soil mesocosms were maintained for 7months and watered each week with 300ml of distilled water. At the end of this period the soil columns were divided into upper and lower halves and microbial biomass carbon and functional diversity assessed. Greater microbial biomass and activity was found in the upper layer of soil. Food supply was the major driver leading to increased microbial activity and biomass. Increased earthworm biomass had the opposite effect. In the lower soil layer, the presence of anecic worms had the greatest effect on microbial biomass and activity. This effect was enhanced with increased food supply. Overall, the relationship between earthworm functional diversity and microbial community level physiological profile appeared to be idiosyncratic and the effect of the earthworms varied with soil layer, initial biomass and food supply. The loss of any earthworm functional group might lead to significant alterations in the microbial biomass, distribution and physiological profile. [Copyright &y& Elsevier]

Abstract: In this paper we summarize the current knowledge on earthworm diversity in the central part of the Balkans, in the State of Serbia. Up to now, 71 species and 8 subspecies, belonging to 18 genera, are known from investigated territory. Our aim was to produce a single priority list for earthworm conservation, particularly as the Balkan countries did not have their own Red Lists for earthworms and none of the species had a legally protected status. The list underlines the diversity of earthworms, zoogeographical position as well as category of threat. The analysis based on the IUCN (2001) Red List Categories shows that 17 of 79 taxa are Critically Endangered (5 species are serious Critically Endangered, but 12 species are only suspect for the Critically Endangered category), 9 species are Endangered and 14 species are Vulnerable. Serious candidates for their inclusion in CR category within the IUCN (2001) Red List are: Cernosvitovia biserialis, Dendrobaena kozuvensis, Lumbricus improvisus, Serbiona kosowensis montenegrina and Serbiona serbica. Of all registered earthworms, 34 taxa (43.1%) were identified only as endemic species. Unfortunately, most of the high-priority species are endemic (23 taxa). The position of the Central Balkans contributes to the great biodiversity of earthworms on its territory, but the fact that nearly 36% of its lumbricids are threatened is a strong signal that action is required. [Copyright &y& Elsevier]

Abstract: Earthworm surveys were conducted on the Isle of Rum (NNR), Inner Hebrides, Scotland. Fifteen species were located representing all three ecological groups of earthworm. Most species have a very limited distribution, around current or former centres of human habitation and are associated with anthropic activity. Bulk addition of mainland soil at Kinloch provided conditions that now support 12 species (greatest diversity recorded). Three species Dendrodrilus rubidus, Dendrobaena octaedra, and Lumbricus rubellus are almost ubiquitous across Rum, occurring on acidic moorland and to the summit of the highest peak (812 m). Fertiliser addition at such altitude to patchy, herb-rich Calluna heath, has led to greater earthworm numbers but no more species. Where woodland has been re-established on moorland, earthworm communities showed significantly increased numbers (up to 170 m–2 with a mass of 25 g m–2) and increased diversity compared with associated moorland (approximately 10 m–2). It is suggested that selected earthworms, such as Aporrectodea caliginosa and L. rubellus may have a role in assisting soil development and woodland establishment, so their use in the continuing Rum afforestation programme ought to be considered. [Copyright &y& Elsevier]

Restored soils are often low in organic matter (OM). As a result, OM is applied to increase soil fertility. Earthworms can assist soil incorporation of OM, but feeding behaviours, and as a result their roles in this process, differ between species. Laboratory experiments examined the effects of OM availability on the growth and behaviour of Aporrectodea longa and Lumbricus terrestris. Hatchling growth was recorded from 1 l vessels containing soil and OM (separated cattle solids), either surface applied (SUR) or mixed into the soil (MIX). Growth of L. terrestris was also recorded where separated cattle solids (SCS) were concentrated in bands at the surface (SUR) or at depths of 0.03 (UPP) or 0.08 m (LOW). In a further experiment, L. terrestris and L. rubellus were kept in mono-species cultures and paired combination, in treatments with selected SCS placements, which allowed assessment of OM position on species interactions. After 28 weeks, both L. terrestris and A. longa exhibited significantly greater growth rates (P < 0.05) in SUR treatments. The behaviour of both species changed with time. L. terrestris were located in areas where OM was concentrated. After 24 weeks, mean masses of 3.1, 2.2 and 1.6 g were recorded for SUR, UPP and LOW treatments, respectively. Where L. rubellus and L. terrestris were co-cultured, the former had significant (P < 0.05) negative effects on the growth of the latter, but only when surface OM was limited. At restored sites, application of OM may be important in the development of sustainable earthworm populations and hence their role in soil amelioration. [Copyright &y& Elsevier]