Impact of the earthworm Lumbricus terrestris on the degradation of Fusarium-infected and deoxynivalenol-contaminated wheat straw     

Elisabeth Oldenburg  Susanne Kramer  Stefan Schrader  Joachim Weinert 《Soil biology & biochemistry》2008,40(12):3049-3053

When conservation tillage is practised in agriculture, plant residues remain on the soil surface for soil protection purposes. These residues should be widely decomposed within the following vegetation period as microbial plant pathogens surviving on plant litter may endanger the currently cultivated crop. Important soil-borne fungal pathogens that preferably infect small grain cereals belong to the genus Fusarium. These pathogens produce the mycotoxin deoxynivalenol (DON), a cytotoxic agent, in infected cereal organs. This toxin frequently occurs in cereal residues like straw. So far it is unclear if DON degradation is affected by members of the soil food web within decomposing processes in the soil system. For this purpose, a microcosm study was conducted under controlled laboratory conditions to investigate the degradation activity of the earthworm species Lumbricus terrestris when exposed to Fusarium-infected wheat straw being contaminated with DON.Highly Fusarium-infected and DON-contaminated straw seemed to be more attractive to L. terrestris because it was incorporated faster into the soil compared with straw infected and contaminated at low levels. This is supported by a greater body weight gain (exposure time 5 weeks) and smaller body weight loss (exposure time 11 weeks) of L. terrestris, respectively, when highly contaminated straw was offered for different time periods.Furthermore, L. terrestris takes part in the efficient degradation of both Fusarium biomass and DON occurring in straw in close interaction with soil microorganisms. Consequently, earthworm activity contributes to the elimination of potentially infectious plant material from the soil surface.  相似文献   

长江三角洲地区城市污泥对蚯蚓的急性毒性效应   总被引：2，自引：0，他引：2  

申荣艳  骆永明  李振高  滕应  章钢娅 《土壤》2008,40(5):738-743

应用滤纸法和自然土壤法测定了长江三角洲地区城市污泥及其与青紫泥混合后对蚯蚓的急性致死效应及慢性毒性效应。结果表明:滤纸法测定的污泥对蚯蚓的毒性症状出现快且严重,不同污泥对蚯蚓的毒性大小差别较大,致死中浓度(LC50)相对应的污泥与水比值(Rsw-LC50)范围在0.0010～0.0242之间。在供试的城市污泥中,上海贮泥池污泥对蚯蚓的毒性最大,上海脱水污泥5对蚯蚓的毒性最小。自然土壤法测定的污泥与土壤作用后对蚯蚓的毒性结果为:所有处理蚯蚓死亡率均为0,各污泥处理对蚯蚓体重增长率的影响差别不大,个别污泥处理蚯蚓体重增长率比对照处理低,即对蚯蚓的体重有负增长影响。与滤纸法各处理相比,中毒症状较轻微,仅极个别中毒症状较明显。与污泥的水浸液相比,污泥与土壤作用后对蚯蚓的毒性大大降低。  相似文献   

Above-ground earthworm casts affect water runoff and soil erosion in Northern Vietnam   总被引：1，自引：0，他引：1  

Pascal Jouquet  Pascal Podwojewski  Nicolas Bottinelli  Jérôme Mathieu  Maigualida Ricoy  Didier Orange  Toan Duc Tran  Christian Valentin 《CATENA》2008

  相似文献   

Ecological detoxification of methamidophos by earthworms in phaiozem co-contaminated with acetochlor and copper     

Qixing Zhou  Meie Wang  Jidong Liang 《Applied soil ecology》2008,40(1):138-145

In view of the ubiquitous co-existence of methamidophos, acetochlor and copper (Cu) in agricultural soils, ecological detoxification of methamidophos in phaiozem by earthworms was examined using the detoxic incubation experiments with illumination. It was validated that the earthworm Eisenia fetida is a useful soil animal in the process of methamidophos detoxification as the assistance of soil microbes and enzymes. Due to the action of earthworms, the half life of methamidophos with concentration of 15 mg/kg in phaiozem could decrease from 5.61 days to 5.08 days. Dynamics of methamidophos detoxification by earthworms could conform to the logistic model. Under the condition of multiple pollution combined with acetochlor (20 mg/kg) and Cu (300 mg/kg), ecological detoxification of methamidophos by earthworms became complicated. Acetochlor played a promoting role in the biodegradation of methamidophos to some extent, while it was basically inhibited by Cu.  相似文献   

Comparative analysis of Andiodrilus pachoensis casts in forests and pastures of South-Eastern Amazon (Brazil)     

Fabien Thomas  Jean-Pierre Rossi  Thibaud Decaëns  Michel Grimaldi  Patrick Lavelle  Paulo Fernando da Silva Martins  Evelyne Garnier-Zarli 《European Journal of Soil Biology》2008,44(5-6):545

Soil ecosystem engineers produce biogenic structures (casts, mounds, galleries) that strongly affect soil processes. A comparative analysis of the physical characteristics of the casts produced by the earthworm Andiodrilus pachoensis was carried out in four pastures sowed with Brachiaria brizantha and four primary forests on the deforestation front of the Amazonian forest. In both systems, we recorded surface cast density and spatial patterns as well as surface cast physical properties. Cast and vegetation distributions were mapped within plots of sizes ranging from 25 to 50 m², and cast production was monitored during 2 months. Cast spatial distribution varied greatly among plots and across spatial scales ranging from regular at small spatial scales (0–20 cm) to clumped for larger distance ranges (>80 cm). Cast density was not significantly correlated with grass tuft density and their production was independent from the presence of grass tufts in pastures or litter quantity in forests. Although bulk soil properties (pH, C content, structural stability, etc) differed between pastures and forests, cast physical properties did not differ significantly among the studied ecosystem.  相似文献   

Earthworm communities in native savannas and man-made pastures of the Eastern Plains of Colombia     

J. J. Jiménez  A. G. Moreno  T. Decaëns  P. Lavelle  M. J. Fisher  R. J. Thomas 《Biology and Fertility of Soils》1998,28(1):101-110

 The structure and seasonal changes of earthworm communities were evaluated in a natural savanna and in a improved grass-legume pasture in a Colombian oxisol over a period of 18 months. One plot of 90×90 m was isolated in each of the systems and each month five samples of 1 m²×0.5 m and ten of 20×20×20 cm were randomly selected from a stratified block design. Species richness was similar in the two evaluated plots (seven species), whereas diversity measured by the index, H (Shannon and Weaver 1949) was clearly different, i.e. H=2.89 in natural savanna and H=1.29 in pasture. This is explained by differences in earthworm community structure. The average annual density in the savanna was 49.8, ranging from 10.8 to 135.8 individuals (ind) m^–2, and biomass was 3.3 g m^–2 (hand-sorting method), ranging from 0.9 to 11.5 g m^–2. In the man-made pasture, density was 80.1 ind m^–2 on average, ranging from 24 to 215.8 ind m^–2 and biomass was more than tenfold higher, ranging from 29.2 to 110.4 g m^–2. This was especially due to the presence of a large glossoscolecid anecic species, Martiodrilus carimaguensis Jiménez and Moreno, which has been greatly favoured by conversion of savanna to pasture. Endogeic species were dominant in the natural savanna whereas the anecic species accounted for 88% of total earthworm biomass in the pasture. Total earthworm density and biomass were significantly different in the two systems studied (t-test). The results indicate a clearly positive response of earthworm communities to improved pastures, a type of land use that is being increasingly adopted in moist neotropical savannas. Received: 20 October 1997  相似文献   

Lumbricus terrestris L. distribution within an experimental humus mosaic in a mountain spruce forest     

Bernier  N.  Ponge  J.-F. 《Biology and Fertility of Soils》1998,28(1):81-86

 An experiment was designed at a mountain site to study the distribution of adult Lumbricus terrestris in relation to a small-scale mosaic of humus forms representative of different stages of a spruce forest ecosystem. Good agreement was found between distribution in the mosaic and that in the field. ANOVA tests demonstrated the strong influence of humus form on earthworm abundance when comparing a vermimull (high earthworm burrowing activity) taken from a spruce regeneration site (61.8 individuals m^–2) with a leptomoder (no earthworm burrowing activity) taken from a 60-year-old spruce stand (6.2 individuals m^–2). Other humus forms were intermediate (mean density 34.6 individuals m^–2). The same pattern was found with individual biomass, but with lower significance. Main differences observed in the experimental design were attributed to the immediate carrying density of the humus forms. A distinction was made between humus profiles built up with or without spruce cover. In the latter case (regeneration site and bilberry heath), the immediate carrying capacity indicated by the experimental approach overestimated the field density by a factor of 4. Under spruce this overestimate was even higher (approximately 10 times too high in an adult spruce stand (160 years old) and 30 times too high under moss cover). The increase in density due to experimental conditions was not determined for leptomoder humus accumulated under the actively growing spruce stand (60 years old) since the earthworm density was near zero in both cases. Relationships between humus form and earthworm populations are discussed. Received: 9 June 1997  相似文献   

蚯蚓及其在环境保护上的应用 I.蚯蚓及其在自然生态系统中的作用   总被引：3，自引：0，他引：3  

邱江平 《上海交通大学学报(农业科学版)》1999,(3)

蚯蚓是土壤中的主要动物类群,在陆地生态系统中具有重要的功能。蚯蚓促进植物残枝落叶的降解,有机物质的分解和矿化这一复杂的过程,并具有混合土壤、改善土壤结构、提高土壤透气、排水和深层持水能力的作用。它们的这些作用与其生物量和三种生态类型（ 表层种、内层种和深层种） 密切相关。  相似文献   

双齿围沙蚕与赤子爱胜蚓对凡纳滨对虾生长和免疫指标的影响   总被引：5，自引：1，他引：5       下载免费PDF全文

刘石林  刘鹰  杨红生  游奎  陈慕雁  俞立东 《中国水产科学》2006,13(4):561-565

以鲜活饵料双齿围沙蚕（Perinereis aibuhitensis）、赤子爱胜蚓（Eisenia foetida）和人工配合饵料投喂凡纳滨对虾（Litopenaeus vannamei），并测定各种饵料对其生长和免疫指标的影响。结果表明，沙蚕和蚯蚓单独投喂或与人工配合饵料配合投喂都可显著提高凡纳滨对虾的生长速率，但用沙蚕单独投喂的对虾成活率较低。蚯蚓与人工配合饵料配合投喂可显著提高对虾血清中抗菌活力、溶菌活力、酚氧化酶活力和血细胞数量；蚯蚓单独投喂可显著提高血清中抗菌活力、酚氧化酶活力和血细胞数量，对血清中溶菌活力作用不明显。沙蚕与人工配合饵料配合投喂可显著提高对虾血清中抗菌和溶菌活力．但对血清中酚氧化酶活力和血细胞数量变化作用不明显；单独投喂沙蚕对所测各项免疫指标影响均不显著。研究结果证实：利用蚯蚓和沙蚕可显著提高对虾的生长速率，但蚯蚓的饵料效果优于沙蚕。[中国水产科学，2006，13（4）：561—565]  相似文献   

Axial pressures generated by the earthworm Aporrectodea rosea     

B. M. McKenzie  A. R. Dexter 《Biology and Fertility of Soils》1988,5(4):323-327

Summary The axial forces generated by the earthworm Aporrectodea rosea were measured by directing the earthworm to tunnel into soil discs mounted on an electronic balance connected to a datalogger. The area over which the force acted was estimated from the size of the hole created by the tunnelling. The maximum force recorded by an individual worm was 0.760 N and the mean maximum value was 0.465 N. The maximum pressures recorded was 116.5 kPa, while the mean maximum pressure was 72.8 kPa. These axial pressures are approximately one-tenth of the maximum axial pressure recorded for plant roots. The statistical distribution of activity as the worms tunnelled through the soil discs was analysed. Pressures recorded were well in excess of physiologically measured pressures and the generation of forces within muscles to achieve these pressures was calculated by some assumptions. It was estimated that there is a maximum tension in the circular muscles of 0.15 N per segment of the worm.  相似文献