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1.
通过急性毒性试验测定了不同培养条件下Pb对蚯蚓的毒害作用,并通过牛粪、砖红壤培养试验,测定了蚯蚓对Pb的忍耐性,及不同形态Pb对蚯蚓体重的影响。研究结果如下:蚯蚓在在液、沙、泥土和干牛粪中的急性半致死剂量(LD50)分别为354.41 mg/kg、360.95 mg/kg、1228.02 mg/kg和3894.62 mg/kg。蚯蚓在腐熟牛粪中对Pb有很好的忍耐性,当牛粪中Pb含量达到15000 mg/kg时蚯蚓依然能够生存。蚯蚓在Pb污染砖红壤生活60d后回收率和体重均有下降,在土壤Pb含量分别为400 mg/kg和444 mg/kg时蚯蚓的回收率和增长率下降最快,分别为0.6403和-0.4358。限制蚯蚓增长的程度大小Pb形态依次为:碳酸盐结合态>交换态>有机态>无定形氧化锰结合态>晶形氧化铁结合态>无定形氧化铁结合态>残渣态  相似文献   
2.
In Colombia, more than 1 million tons of coffee pulp are produced every year. Its transformation into compost by means of turned piles has led to a final product with poor physical and chemical characteristics and vermicomposting has been suggested as an alternative method of transforming these wastes into a useful organic fertilizer. The ability of the earthworm Eisenia fetida to transform coffee pulp into a valuable compost was evaluated. The influence of bed depth and time on different C fractions, N content and availability of nutrients was studied. The results showed that the C and N contents were not affected by the depth of the bed, whereas time affected both. An increase in the fractionation ratio, determined by calculating the C in the fraction smaller than 100 m as a percentage of C in the samples as a whole, and low values of humic-like substances were recorded during vermicomposting. After ingestion of the pulp by the earthworms, an increase in available P, Ca, and Mg but a decrease in K were detected.  相似文献   
3.
为探寻从蚯蚓匀浆液中制备蚯蚓纤溶酶(EFE)的简便途径,利用亲和层析的方法,分别从新鲜制备的与多年存放的蚯蚓匀浆液中制备了新、旧蚯蚓纤溶酶(即新、旧EFE)。利用天然电泳、SDS-PAGE纤维蛋白活性电泳分析组分差异,通过纤维蛋白平板比较两者纤溶酶活性,发现蚯蚓匀浆液在存放过程中,EFE的部分组分发生降解,但EFE的比活却升高了1.4倍。  相似文献   
4.
为检测市面上某种农用酚醛泡沫的使用安全性,采用人工土壤法研究酚醛泡沫对赤子爱胜蚓的急性毒性;同时测定了酚醛泡沫暴露64 d后的慢性毒性效应,对蚯蚓超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活性的影响,并分析了土壤中性磷酸酶(S-NP)、脲酶(S-UE)活性和呼吸速率的变化,探讨了酚醛泡沫对土壤活性及功能的影响。结果表明:酚醛泡沫对赤子爱胜蚓的急性半致死浓度大于5 000 mg·kg-1;酚醛泡沫(1~5 000 mg·kg-1)处理64 d后,蚯蚓GSH-Px活性变化范围为27.47~56.96U·mg-1,SOD活性变化范围为32.43~58.10 U·mg-1,两种酶活性均显著增加(P<0.05)。不添加酚醛泡沫的对照处理土壤呼吸速率为0.067 μmol·g-1·h-1,添加酚醛泡沫的处理组为0.041~0.055 μmol·g-1·h-1,表明酚醛泡沫添加显著(P<0.05)抑制了土壤呼吸;但酚醛泡沫处理对土壤S-NP和S-UE活性没有显著影响。研究表明,酚醛泡沫材料(5 000 mg·kg-1)对蚯蚓没有致死作用,但会诱导蚯蚓酶活性显著增强,抑制土壤呼吸速率。  相似文献   
5.
ABSTRACT:   The effects caused by suspended particles in seawater and sediment cover of the substrate on the attachment to the substrate of zoospores, and on the subsequent growth and survival of gametophytes of the brown alga Eisenia bicyclis were examined in the laboratory. The attachment rate to the substrate of the zoospores was remarkably reduced by the sediment cover on the substrate, and it decreased to 3.8% of the no-sediment control by a slight sediment cover of 3.0 mg/cm2 (0.048 mm in thickness). The growth of gametophytes was not inhibited at 10 mg/cm2 or less of sediment cover, though it was stopped at 30 mg/cm2. The survival rate of gametophytes became 39.4% at 5 mg/cm2 on the substrate, and gametophytes were all blighted at 30 mg/cm2. The ratio of male to female of the surviving gametophytes became 81.5:18.5, when the sediment cover was 10 mg/cm2. The rate of total loss ( TL [%]) of zoospores and gametophytes of Eisenia bicyclis was obtained from the following equation: TL  = 100 (1 − exp[−0.0339  C ] exp[−1.24  Q ]), where, C (mg/L) and Q (mg/cm2) indicate the concentration of suspended particles in seawater and the sediment on the substrate, respectively.  相似文献   
6.
Nanoparticles (NPs) of TiO2 and ZnO are receiving increasing attention due to their widespread applications. To evaluate their toxicities to the earthworm Eisenia fetida (Savigny, 1826) in soil, artificial soil systems containing distilled water, 0.1, 0.5, 1.0 or 5.0 g kg−1 of NPs were prepared and earthworms were exposed for 7 days. Contents of Zn and Ti in earthworm, activities of antioxidant enzymes, DNA damage to earthworm, activity of cellulase and damage to mitochondria of gut cells were investigated after acute toxicity test. The results from response of the antioxidant system combined with DNA damage endpoint (comet assay) indicated that TiO2 and ZnO NPs could induce significant damage to earthworms when doses were greater than 1.0 g kg−1. We found that Ti and Zn, especially Zn, were bioaccumulated, and that mitochondria were damaged at the highest dose in soil (5.0 g kg−1). The activity of cellulase was significantly inhibited when organisms were exposed to 5.0 g kg−1 of ZnO NPs. Our study demonstrates that both TiO2 and ZnO NPs exert harmful effects to E. fetida when their levels are higher than 1.0 g kg−1 in soil and that toxicity of ZnO NPs was higher than TiO2.  相似文献   
7.
8.
Summary Many of the most widely distributed species of Lumbricidae are polyploid. So far polyploid forms have been found to be distributed more widely than diploid ones. Taking Eisenia nordenskioldi as an example, it was shown that polyploids are able to occupy new ecological niches within the area of the diploid form. Ecological differences observed in representatives of different chromosomal races provide polyploids with the chance to coexist in one biocurrent, occupying different ecological niches.Dedicated to the late Prof. Dr. M.S. Ghilarov  相似文献   
9.
Summary Although moisture requirements of Eisenia fetida are considered to be generally known, very few in-depth studies have been performed. The moisture preferences of juveniles as well as adults of this species were determined in moisture towers containing cow manure with a particle size bigger than 500 and smaller than 1000 m and an organic matter content of 54%. The clitellate worms showed a wider preference range than the juveniles but deposited most of their cocoons within the narrow range of 65%–70% moisture — a moisture range preferred by 80% of the juveniles. Growth studies of newly hatched worms at various moisture levels over a period of 90 days showed that growth rate and final biomass were influenced by moisture availability with a very low rate of growth at low as well as at high moisture levels. The change in biomass of clitellate specimens as well as their consecutively produced cocoons were monitored at different moisture levels. A clear relationship between mass of cocoons and biomass of the producing worms was established at presumably favourable moisture conditions. Furthermore, the relation between cocoon mass and the production rate of cocoons was also determined, which showed that cocoon mass increased concomitantly with increase in cocoon production. The study also showed that clitellum development was increased at moisture levels above 64%. The onset of cocoon production was, however, earliest at slightly lower moisture levels, from which it is concluded that the optimal moisture level for growth and development of clitella are not necessarily optimal for the production of cocoons.Dedicated to the late Prof. Dr. M.S. Ghilarov  相似文献   
10.
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