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霍甫水丝蚓(Limnodrilus hoffmeisteri)扰动对表层沉积物细菌群落结构和多样性的影响  [PDF]
农业环境科学学报 , 2011,
Abstract: 为研究大型底栖动物霍甫水丝蚓(Limnodrilushoffmeisteri)对表层沉积物中细菌群落结构和多样性的影响,设计了沉积物-水微宇宙的实验,模拟太湖梅梁湾霍甫水丝蚓(Limnodrilushoffmeisteri)的自然分布特征,运用末端限制性片段长度多态性技术(T-RFLP)比较了有无霍甫水丝蚓(Limnodrilushoffmeisteri)分布的沉积物样品中细菌群落的动态变化。结果表明,水丝蚓组和对照组沉积物细菌群落结构相似性无显著差异(P>0.05),可见太湖梅梁湾目前的水丝蚓生物量引起的生物扰动对表层沉积物细菌群落结构影响不明显;实验中后期只在处理组中出现的206bp以及处理组含量高于对照组的370bpT-RFs都可能是Nitrosomonas属的氨氧化细菌,提示大型底栖动物霍甫水丝蚓的存在可能为氨氧化细菌提供了适合的生态位。
The effect of temperature on the reproduction of Limnodrilus hoffmeisteri (Oligochaeta: Tubificidae)
Nascimento, Haroldo L. S.;Alves, Roberto G.;
Zoologia (Curitiba) , 2009, DOI: 10.1590/S1984-46702009000100026
Abstract: the tubificid worm limnodrilus hoffmeisteri claparede, 1862 is widely used as an indicator of organic pollution in aquatic environments. nevertheless, little is known about its biology. the present work aimed to compare the reproductive rate of l. hoffmeisteri raised at three different temperatures (15, 20 and 25°c). seventy-five adult individuals were kept in fifteen 250 ml beakers (five individuals per beaker) containing sand and dechlorinated tap-water each. beakers were arranged so as to form three groups of five. each group was kept in a given temperature for 21 days. results show that worms raised at 25°c produced a significantly larger number of eggs compared to those raised either at 15 or 20°c, as observed in the tropical tubificid branchiura sowerbyi beddard, 1892.
Influence of body weight and substrate granulometry on the reproduction of Limnodrilus hoffmeisteri (Oligochaeta: Naididae: Tubificinae)
Lobo, Haroldo;Alves, Roberto G.;
Zoologia (Curitiba) , 2011, DOI: 10.1590/S1984-46702011000500002
Abstract: limnodrilus hoffmeisteri claparede, 1862 is a cosmopolitan oligochaeta widely used as indicator of organic pollution in water bodies. previous contributions have shown the effects of organic matter and temperature on the life history of the species, although very little is known about the factors that influence its reproduction. this study aimed 1) to test whether the larger weight of individuals results in an increase in the reproduction rate and 2) to test the influence of two granulometric fractions of sand on the reproduction and growth the species. in the first experiment, specimens of l. hoffmeisteri were separated in two groups with different average weights (small individuals = 6.63 ± 1.28 mg; large individuals = 12.44 ± 3.99 mg) and kept at 15 ± 1oc for 21 days. the results of this experiment showed that the number of cocoons was statistically similar between the groups, but the mean number of eggs per cocoon produced by large individuals (2.78 ± 0.35) was greater than that produced by small individuals (7.45 ± 2.50). in the second experiment, weekly observations were conducted for 25 weeks in two groups of 30 specimens: one kept in fine sand and the other in medium sand, at 25 ± 1oc. the single significant difference was in the number of cocoons per adult per day (0.37 ± 0.22 and 0.23 ± 0.24, for fine and medium sand, respectively). individuals reared in fine sand produced a greater number of descendants compared to those reared in medium sand in the same period of time.
Toxic effects of BTEX in water on Daphnia magna and Limnodrilus hoffmeisteri and safety assessment of the aquatic environment

FAN Yawei,ZHOU Qixing,WANG Yuanyuan,ZHU Shuang,

环境科学学报 , 2009,
Abstract: Aquatic ecotoxicological effects of toluene, ethylbenzene and xylene were investigated using Daphnia magna and Limnodrilus hoffmeisteri as test living organisms. The results indicated that there were significantly positive correlations between the inhibitory or lethal effects on Daphnia magna and Limnodrilus hoffmeister and the concentrations of the three chemicals in aquatic environment. The toxic action was increased with prolongation of the exposure time. The 24 h EC50 values of toluene, ethylbenzene and xylene to Daphnia magna were 172.1, 50.1 and 63.6 mg·L-1, and the 48 h EC50 values were 136.9, 42.9 and 50.3 mg·L-1, respectively. The 24 h LC50 values of toluene, ethylbenzene and xylene to Limnodrilus hoffmeisteri were 194.8, 71.9 and 88.0 mg·L-1, the 48 h LC50 values were 185.2, 46.8 and 75.6 mg·L-1, and the 96 h LC50 values were 170.4, 38.8 and 71.9 mg·L-1, respectively. According to the results of the acute toxicity tests on Daphnia magna and Limnodrilus hoffmeister, the predicted safe concentrations (SC) of toluene, ethylbenzene and xylene in the aquatic environment were 13.7, 3.9 and 5.0 mg·L-1, and their maximum permissible concentrations (MPC) were 1.4, 0.4 and 0.5 mg·L-1, respectively.
Captación de malatión en sedimentos artificiales y su efecto tóxico sobre Limnodrilus hoffmeisteri  [cached]
Laura Martínez Tabche,Marcela Galar Martínez,Elena Olvera Hernández,Alejandro Chehue Romero
Revista internacional de contaminación ambiental , 2001,
曹添教授逝世  [PDF]
地质论评 , 1983,
Abstract: 我国知名地球化学家、武汉地质学院教授、中国地质学会勘查地球化学事业委员会副主任委员、《地质学报》和《地质论评》编辑委员会委员曹添教授,因病抡救无效于1982年11月12日在北京逝世,终年56岁。
The influential of physico-chemical parameters on the distributions of oligochateas (Limnodrilus sp.) at the polluted downstream of the tropical Langat River, Peninsular Malaysia
CK Yap, A Ismail Rahim, MZ Azrina, A Ismail, SG Tan
Journal of Applied Sciences and Environmental Management , 2006,
Abstract: The influential physico-chemical parameters on the spatial and temporal distribution of oligochateas (Limnodrilus sp.) at the polluted downstream of Langat River were studied in comparison to the unpolluted upstream for 10-months sampling from March 1998 to February 1999. Based on the correlation analysis (CA) and multiple stepwise regression analysis (SRA), the distribution, abundance and density of Limnodrilus sp. were almost consistent during the ten time samplings from April 1998 to February 1999. Based on CA, the density and distribution of Limnodrilus sp. correlated negatively with the pH and dissolved oxygen (DO) while positively correlated with conductivity, biological oxygen demand (BOD), NO3, NH3, total suspended solids (TSS), chemical oxygen demand (COD) and dissolved concentrations of Cu and Zn. Based on SRA, most of the above parameters are selected as influential factors in affecting the distribution and presence of Limnodrilus sp. on the tropical river. This indicated that the Limnodrilus sp. is a pollutant resistant worm since they can survive in the poor water quality ecosystem. These results based on CA and SRA signified the resistance and tolerance of Limnodrilus sp. survived at the polluted ecosystem of the tropical river. Hence, Limnodrilus sp. is a good bioindicator of polluted rivers in the tropical ecoregion. Journal of Applied Sciences and Environmental Management Vol. 10(3) 2006: 135-140
Characteristics of microfauna and their relationships with the performance of an activated sludge plant in China

ZHOU Kexin,XU Muqi,LIU Biao,CAO Hong,

环境科学学报(英文版) , 2008,
Abstract: The occurrence and abundance of the microfauna groups were compared with the physico-chemical and operational parameters of the Baoding Lugang Sewage Treatment Plant in China. Attached and crawling ciliates were the dominant groups of ciliates. Crawling ciliates and testate amoebae showed a strong association with effluent BOD5 (biochemical oxygen demand). Therefore, these two groups are likely to be useful bioindicators since their number decreased as the process produced poor quality effluent. Testate amoebae also had significant negative correlations with effluent TN (total nitrogen), NH4 -N, SS (suspended solids) and SVI (sludge volumetric index), which means that this group of ciliates may be indicators of good performance of the activated sludge system. Carnivorous ciliates and flagellates had significant positive correlations with SVI, suggesting that these two groups may be indicators of bad settlement conditions of sludge. As identification of the microfauna species is difficult and time-consuming, we recommend using microfauna functional groups to evaluate the performance of the activated sludge system.
李白《梁甫吟》的创作时间  [PDF]
天府新论 , 1988,
Abstract: 对李白的《梁甫吟》,萧士赟认为,此诗“太白灼见当时贵妃、国忠、林甫、禄山窃弄国柄,祸已胎而未形,欲谏则言无证而不信,倘使君王不鉴吾之诚,则正所谓杞人忧天之类耳”,不免笼统而失当。《唐宋诗醇》以为:“此诗当亦遭谗被放后作,与屈平眷顾楚国,同一精诚。”笼统同前,盖承萧说而稍变之。詹锳《李白诗文系年》远引宋杨遂《李太白故宅记》及《韵语阳秋》,并引萧氏之说及沈德潜《唐诗别裁》之论,以《唐宋诗醇》之见为是,而举《冬夜醉宿龙门觉起言志》诗云:“富贵不可期,殷忧向谁写?去去泪满襟,举声
Biochemical and Mitochondrial Changes Induced by Cd, Fe and Zn in Limnodrillus hoffmeisteri
Grajeda y Ortega,María de los Angeles; Ortiz Ordo?ez,Esperanza; Favari,Liliana; Shibayama,Mineko; Silva Olivares,Angélica; López López,Eugenia;
International Journal of Morphology , 2011, DOI: 10.4067/S0717-95022011000200018
Abstract: the effects of sublethal concentrations of cadmium (0.64 μg/l), iron (0.043 mg/l) and zinc (0.31 mg/l) and a mixture of these metals on succinate dehydrogenase (sd) and alkaline phosphatase (ap) activity and on structural changes in the mitochondria of epithelium cells of the digestive tract were examined in the oligochaete limnodrillus hoffmeisteri after 96 h of exposure in artificial sediments. sd activity was significantly inhibited, particularly in treatments with cd alone (92.57%), while ap increased its activity with cd alone (73.23%). however, when this metal was mixed with fe and zn, the inhibition of sd activity was lower (67.82%) than with cd alone, showing an antagonistic effect and ap increased its activity (73.26%). mitochondria were structurally damaged by exposure to cd alone. however, in the metal mixtures, the toxic effects may exert interactive effects eliciting a less structural damage in the mitochondria of epithelium cells of the digestive tract than when cd is alone.
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