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1.
The analysis presents earthworm distribution in eight designated tectonic units (C—Cyprus, EP—East Pondites, ET—East Taurus block, Sc—Sakarya continent, Kb—Kırşehir block, L—the Levant, TM—Taurus–Menderes block, WP—West Pondites) in the East Mediterranean region (EM). It represents a full list of earthworm species (N = 81) of the region and reveals significant faunal similarities between Sc + WP, and between Kb + TM. The new Sc + WP unit is characterized by the presence of archaic (Spermophorodrilus) as well as modern earthworm fauna. In contrast, the second newly established Kb + TM unit is characterized by poorly presented earthworm autochthonous fauna and by a lack of endemic species. The analysis done on the species list (N = 73) representing the autochthonous family Lumbricidae showed statistically supported separation of L and EP between themselves and from other designated units. The Levant, part of the Arabian tectonic plate, is characterized by a high level of endemism in ancient (Healyella) and modern (Dendrobaena, Perelia) genera, and by the lack of archaic genera. The EP harbors unique species representing archaic (Eophila), ancient (Healyella), and modern (Allolobophora, Aporrectodea, Dendrobaena and Eisenia) earthworm genera in the EM. The analysis also indicates origin of earthworm fauna in TM and faunistic relationships among the designated units. Clearly, the present-day division of the EM earthworm fauna shows recognizable influences of tectonic history.  相似文献   

2.
A new tortoise beetle species, Cyrtonota abrili, is described from the Antioquia and Caldas departments in Colombia. New faunistic data are provided for 87 species, including 16 new additions to the country’s fauna. A checklist of the known 238 species of tortoise beetles recorded from Colombia is given.  相似文献   

3.
Earthworms are important soil metabionts indicative of N enrichment in pastures. A rotational pasture in central Nova Scotia was tested for earthworms using chemical extraction followed by excavation and hand sorting in 28 paired micro plots placed in areas with low versus high proportion of the N indicator plant species dandelion (Taraxacum officinale). Species richness was low with five earthworm species of the Lumbricidae recovered in the following order of abundance: Lumbricus rubellus, Lumbricus terrestris, Aporrectodea turgida, Aporrectodea tuberculata, and Aporrectodea trapezoides. All species occurred at high constancy except the rare A. trapezoides. The inventory revealed spatial differentiation of earthworm abundance and community structure at the field level. High proportion of dandelion reduced pasture sward biomass while abundance of L. rubellus and A. tuberculata significantly (p < 0.05) increased with a concomitant increase in epigeic earthworm dominance at the expense of the anecic L. terrestris. Thus, low cost and non-destructive floristic surveys of N indicators, such as dandelion, allow for concordant inferences about the environmental impact of intensive cow pasture on earthworms and ecosystem function. High earthworm counts may run contrary to the notion of ecological integrity depending on specific earthworm abundances. Reduced earthworm benefits due to any de-intensification of rotational pasture must be assessed against increased risks of N-leaching in intensive pastures with high proportion of dandelion.  相似文献   

4.
This paper studies the impact of a free-ranging bison population on the vegetation and soil fauna in spatially adjacent biotopes (meadow-transition zone-surrounding forest) in the Kaluzhskie Zaseki State Nature Reserve. It is noted that bison maintains meadows in the absence of haymaking. Analysis of phytosociological relevés shows that the forest vegetation has been significantly transformed by bison over 10–15 years, as evident from (1) differences in the ecological-coenotic structure of the vegetation in the different biotopes, (2) a larger ecological-coenotic diversity of communities in the transition zones in comparison with surrounding forests, and (3) an increase in the participation of nitrophilous species in the vegetation. A fairly high earthworm species diversity (a total of seven species in the biotopes) is found; Aporrectodea caliginosa dominates in the earthworm density and biomass. The total earthworm density and biomass became lower in the transition zone than in neighboring forests and meadows, and the differences in earthworm density between the transition zone and the meadows were statistically significant.  相似文献   

5.
A new ichnotaxon, attributed to earthworm aestivation chambers, is described from paleosols of the Sopas Formation (Upper Pleistocene) of northern Uruguay. This ichnofossil consists of a spherical chamber with a constructed wall of imbricated faecal pellets and a filling of rounded to meniscate pellets arranged in winding strings. The strings may also be connected to specimens of Taenidium serpentinum in the paleosol, resulting in a compound trace fossil. Castrichnus incolumis igen. et isp. nov. is interpreted as an earthworm aestivation chamber based on its morphological similarity to the chambers produced by extant earthworms. As such, C. incolumis is considered an indicator of subaerial exposure, and also of seasonal climate. C. incolumis is the second trace fossil that can be attributed with certainty to earthworms. In addition, the CastrichnusT. serpentinum compound specimens indicate that in paleosols, earthworms can be the producers of T. serpentinum. Aestivation chambers would represent a new ethological category.  相似文献   

6.
A new Pliocene (3.4 Ma) mollusk fauna from Mejillones Peninsula, northern Chile is described and compared with the Pliocene La Cueva fauna of little constrained age from central Chile and some species from the Huenteguapi Sandstone overlying the Ranquil Formation on Arauco Peninsula, south central Chile. Preliminary correlation is based on faunal similarities. A total of 45 taxa were identified, of which Cyclocardia kieli sp. nov. is new to science. New combinations are Macron escalonia (Vermeij and DeVries, 1997), Austrofusus steinmanni (Möricke, 1896) and Leukoma antiqua (King, 1832). For several species, the oldest occurrences and range extensions are reported. Co-occurrence of warm water taxa, previously assigned to MIS 11, and typical Pliocene taxa on Mejillones cannot be confirmed. Pliocene and Pleistocene mollusk faunas from Mejillones are listed for comparison.  相似文献   

7.
During a study on the breeding rate of the earthworms Lumbricus rubellus and Eisenia foetida, nematodes identified as Rhabditis terricola were found consistently in large numbers in earthworm cocoons that failed to hatch after an adequate incubation period. This nematode species, which was previously known as a saprophyte, was found to invade earthworm cocoons and reproduce within, causing extensive productivity losses in earthworm cultures. In this study, R. terricola was effectively eradicated from earthworm cultures by rinsing the earthworms in tap water and transferring them repeatedly to sterile bedding.  相似文献   

8.
《Journal of Asia》2023,26(1):102021
Only three species belong to Matileola in previously described species of Keroplatidae from world. Here two species are added to the fauna of Chinese mainland, Matileola motuoensis sp. nov. and Matileola sejilaensis sp. nov., which are described and illustrated as new to science. A key to the species of Matileola from world is presented.LSID: urn:lsid:zoobank.org:pub:09701DF4-61B5-42E4-BF05-EC9E68718758.  相似文献   

9.
Although insects form a large part of the aquatic fauna worldwide, expansive species of aquatic insects are quite rare. Recently, we can observe a tendency to the range expansions in several aquatic insect species. Here, we present the first record of water bug species Anisops sardeus sardeus (Heteroptera: Notonectidae) from Slovakia. This is the northernmost record of this small-bodied backswimmer which is native to Sahelo-Sindian area, extending to Mediterranean. However, the species shows recent range expansion northward in Europe. We document the current distribution of A. s. sardeus in Slovakia and Europe, and discuss the drivers of expansion and possible impact of the alien species on resident fauna.  相似文献   

10.
The abundances and activities of earthworms in arable lands depend strongly on management practices and; therefore earthworm can act as a potential bioindicator of land use practices. In this study earthworm diversity and abundances was measured in three differently managed agro-ecosystems i.e. conventional, integrated and organic, in some sites of northern semiarid region of India. The maximal numbers of earthworm occurrence were in integrated farming system (100%, all studied sites showed the presence) followed by organically managed (70%) and conventional (18.9%) agro-ecosystems. A total of six species belonging to four different families were identified during this survey and all recorded earthworm species were present in organically managed agro-ecosystems, while integrated and conventional arable lands exhibited only three earthworm species. The abundance of earthworms in arable system was also directly related to the management practices. The values of ecological indices e.g. Shannon diversity (H′), species dominance (C), the species richness (S) and evenness (E) indicated the anthropogenic pressure on earthworm communities in arable lands of northern India.  相似文献   

11.
《Palaeoworld》2015,24(4):430-437
A new eocrinoid locality of the Balang Formation (Cambrian Series 2) near Kaili City is reported. The fauna is associated with index trilobites, such as Redlichia (Pteroredlichia) murakamii Resser and Endo in Kobayashi, 1935 and Arthricocephalus chauveaui Bergeron, 1899, that are common in the Balang Biota (Cambrian Series 2) but absent in the younger Kaili Biota (Cambrian Series 3). This new locality contains a new eocrinoid fauna (n = 22) that is different from Guizhoueocrinus yui Zhao, Parsley and Peng, 2007a in bearing a smaller theca, a shorter stalk, and a robust attachment disk; thus, a taxon Globoeocrinus zhaoyuanlongensis n. sp. is proposed.  相似文献   

12.
How do earthworms affect microfloral and faunal community diversity?   总被引:17,自引:1,他引:16  
Much of the work regarding earthworm effects on other organisms has focused on the functional significance of microbial-earthworm interactions, and little is known on the effects of earthworms on microfloral and faunal diversity. Earthworms can affect soil microflora and fauna populations directly and indirectly by three main mechanisms: (1) comminution, burrowing and casting; (2) grazing; (3) dispersal. These activities change the soil's physico-chemical and biological status and may cause drastic shifts in the density, diversity, structure and activity of microbial and faunal communities within the drilosphere. Certain organisms and species may be enhanced, reduced or not be affected at all depending on their ability to adapt to the particular conditions of different earthworm drilospheres. A large host of factors (including CaCO3, enzymes, mucus and antimicrobial substances) influence the ability of preferentially or randomly ingested organisms to survive (or not) passage through the earthworm gut, and their resultant capacity to recover and proliferate (or not) in earthworm casts. Small organisms, particularly microflora and microfauna, with limited ability to move within the soil, may benefit from the (comparatively) long ranging movements of earthworms. Microflora and smaller fauna appear to be particularly sensitive to earthworm activities, and priming effects enhancing nutrient release, particularly in casts, are common. Larger fauna such as microarthropods, enchytraeids and Isopods may be enhanced under some conditions (e.g., in earthworm middens), but in other cases earthworm activity may lead to a decrease in their populations due to competition for food (microbes and organic materials), and spatial and temporal changes in food abundance. Nevertheless, considering the presently available data, the beneficial interactions of earthworms and microflora and fauna appear to far outweigh the potential negative effects. However, much is still unknown regarding the interactions of earthworms of different ecological categories on the diversity and function of microfloral and faunal communities, and much more interdisciplinary research is needed to assess the potential role of earthworms in regulating the diversity of microflora and fauna in soil systems and the potentially beneficial or harmful effects this regulation may have on ecosystem function and plant growth in different ecosystems.  相似文献   

13.
To investigate whether earthworm cellulases contribute to the innate immune system, the responsiveness of cellulase activity and mRNA expression to bacterial challenge was examined by zymography and RNA sequencing. A zymographic analysis revealed that the activity levels of earthworm cellulases were upregulated in response to either a bacterial (Bacillus subtilis or Escherichia coli) or LPS challenge. After the challenge, significant increases in cellulase 1 and cellulase 2 activity levels were observed within 8–16 and 16–24 h, respectively. In the coelomic fluid, both activities were significantly upregulated at 8 h post-injection with B. subtilis. Based on RNA sequencing, cellulase-related mRNAs encoding beta-1,4-endoglucanases were upregulated by 3-fold within 6 h after B. subtilis injection. Our results clearly demonstrated that earthworm cellulases are upregulated by bacterial challenge at the mRNA and protein levels. These results support the view that earthworm cellulases act as inducible humoral effectors of innate immunity against bacterial infection.  相似文献   

14.
Soil characteristics influence earthworm population dynamics, species distribution and community structure. According in the present study an attempt was made to determine the soil physiochemical factors influencing earthworms of Kashmir valley with a view to improve the soil productivity by enhancing earthworm diversity under different pedoecosystems. Data collection on 15 soil parameters from 20 earthworm inhabiting sites revealed significant variation within and among the sites in soil temperature (F23, 19 = 148.83, 9.71; P < 0.05), moisture (F23, 19 = 16.91, 46.20; P < 0.05), pH (F19 = 47.21; P < 0.05), electrical conductivity (F23, 19 = 11.67, 87.13; P < 0.05), sodium (F23, 19 = 2.46, 211.25; P < 0.05), potassium (F19 = 22.91; P < 0.05), calcium (F19 = 15.90; P < 0.05), magnesium (F23, 19 = 1.76, 104.51; P < 0.05), organic carbon (F23, 19 = 64.60, 222.50; P < 0.05), organic nitrogen (F23, 19 = 4.59, 3.81; P < 0.05) and phosphorous (F23, 19 = 5.11, 137.87; P < 0.05). Aporrectodea caliginosa trapezoides and A. rosea rosea exhibited wide range of distribution whereas Octolasion cyaneum, A. c. trapezoides and A. parva showed restricted distribution. Hierarchical cluster analysis grouped 20 earthworm collection sites into three clusters—earthworm absent sites, low earthworm diversity sites and moderate earthworm diversity sites. Principal component analysis assisted from the data set of 20 sites, resulting into four latent factors accounting for 77.95 % of total variance, identified the factors affecting earthworm communities are mainly related to physical habitat factor, chemical factor, soil texture factor and growth factor, each accounting for 26.41, 20.16, 18.25 and 13.13 % of total variance respectively.  相似文献   

15.
A new species, Isometrus (Reddyanus) deharvengi sp. n., is described from caves of the region of Hon Chong, Kien Giang in southern Vietnam. Comments are also added about the scorpion fauna of Southeast Asia and cave dwelling buthid scorpions.  相似文献   

16.
《Gene》1997,191(1):97-102
Lysenin, which causes contraction of rat vascular smooth muscle, is a protein that was isolated from the earthworm Eisenia foetida. A cDNA encoding lysenin was isolated by use of a partial cDNA probe that had been generated by the PCR with a primer designed by reference to an internal peptide sequence of lysenin. This clone had an ORF encoding 297 amino acid residues. The amino acid sequence deduced from the cDNA revealed the absence of any significant homology to those of previously characterized vasoactive substances. The recombinant lysenin was produced in Escherichia coli. This protein and native lysenin isolated from the earthworm had similar contractive activities when tested on rat aorta. Northern blot analysis of the RNA from various tissues of the earthworm indicated that lysenin is produced by the coelomocytes.  相似文献   

17.
The ‘New Zealand flatworm’, Arthurdendyus triangulatus, is a native of the South Island of New Zealand, which has established in the UK, Ireland and the Faroe Islands. In its introduced range, it is a predator of lumbricid earthworms. To assess the impact of A. triangulatus on earthworm species, flatworm distributions were manipulated into ‘high’, control and ‘low’ densities within a replicated field experiment. Earthworm biomass in the ‘high’ flatworm density treatment was significantly lower than the control or ‘low’ treatments. This was due to a reduction in the anecic species Lumbricus terrestris and, to a lesser extent, Aporrectodea longa. There was little evidence of negative effects on other earthworm species, with even a weakly positive relationship between flatworm density and epigeic biomass. Principal components analysis showed a clear separation of anecic species from A. triangulatus, but the epigeic species Lumbricus festivus and Lumbricus rubellus grouped with A. triangulatus, suggesting that they could be benefitting from reduced intraguild competition. Flatworm densities of 0.8 per m2, comparable to natural infestations in grassland, were predicted to give a reduction in total earthworm biomass of c. 20 %. The bulk of this was comprised of a reduction in anecic species biomass. In particular, it is considered that A. triangulatus poses a serious risk to L. terrestris populations, with implications for soil functioning and indigenous earthworm-feeding wildlife.  相似文献   

18.
豚草(Ambrosia artemisiifolia)是菊科豚草属的恶性杂草,在我国华南地区已成功入侵并造成严重危害。为了解豚草入侵对中小型土壤动物群落的影响效应,采用野外样地试验法研究了豚草入侵地中小型土壤动物的群落特征。全年4次采样共获得中小型土壤动物4174头,隶属于4门11纲26类,其中线虫类为优势类群,蜱螨目和弹尾目是常见类群。结果显示,豚草入侵改变了中小型土壤动物群落的结构特征,入侵地中小型土壤动物的总个体数以及线虫类、弹尾目动物的个体数显著增加,但中小型土壤动物类群数的变化不明显;在群落的物种多样性方面,豚草入侵显著提高了群落的密度-类群指数,物种丰富度、优势度指数亦有所上升,但差异不明显,而均匀度、Shannon-Wiener指数则趋于下降;在群落相似性方面,入侵区与其它处理区的差异较小。豚草入侵所引起的局部气候环境、凋落物、根系分泌物与土壤理化性质的变化可能是造成中小型土壤动物群落结构特征改变的主要原因。  相似文献   

19.
A new spider species of the extant genus Craspedisia Simon (Araneae: Theridiidae) is described from a fossil in Miocene amber from the Dominican Republic. X-ray computed tomography (CT) was used to reveal important features that were impossible to view using traditional microscopy, because of the position in which the spider is preserved. Craspedisia yapchoontecki sp. nov. is the first described fossil species from this genus and has its closest relative among the extant Hispaniolan fauna.  相似文献   

20.
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