雄性波罗的海灰海豹(Halichoerus grypus)骨组织的矿物密度

本文利用非侵入计算层析X射线摄影法(pQCT)研究了雄性波罗的海灰海豹(4～23岁龄)骨组织的矿物密度(mg/cm3).资料按照收集的年份分组.A组1850～1955年,有机氯(OCs)大量引入之前的时期;B组1965～1985年,OC污染十分严重的时期;C组1986～1997年,OCs浓度逐渐减小的时期.测量结果的复现性良好,变异系数(CV)为0.1%～2.1%.1986～1997年收集的标本中桡骨小梁的矿物密度比1965～1985年收集的标本的明显要高(p＜0.05).1986～1997年收集的标本中,下颌骨的皮层骨矿物密度明显地低于1850～1955年收集的标本(p＜0.05).这些结果表明小梁和皮层骨在一段时间内的不同响应.在OC污染非常严重的时期(1965～1985年),小梁骨矿物密度最低,而在1985～1997年收集的标本中,皮层骨密度最低,该时段是一个OC污染程度相当低的时期.有关这些效应背后的机制目前尚不知道.但是,可以假定这里涉及到OCs.由于目前缺乏有关研究个体中OCs残留水平的资料,因此不可能评估OCs在这方面的影响.     

Influence of bacteria and diatoms in biofilms on metamorphosis of the marine slipper limpet <Emphasis Type="Italic">Crepidula onyx</Emphasis>

Larvae of the slipper limpet Crepidula onyx metamorphose in response to marine biofilms. In this study, we investigated how the percentage of larval metamorphosis in this species was affected by biofilms that differed in certain attributes. To manipulate bacterial and diatom cell densities and community composition, we developed biofilms in the laboratory (1) at different temperatures (16, 23 and 30°C) and salinities (20, 27 and 34‰), (2) with or without addition of antibiotics, and (3) in the light or in the dark. We also allowed biofilms to develop at three field sites with different prevailing environmental conditions so as to generate biofilms with different, but natural, attributes. Bacterial and diatom community composition in biofilms were determined using a DNA fingerprinting technique and microscopic examination, respectively. The effects of biofilms on metamorphosis were investigated in laboratory assays. The percentage of larval metamorphosis correlated with bacterial and diatom cell densities in only one of the three experiments conducted, but was substantially affected by differences in bacterial and diatom community composition in all three experiments. It also appears that metamorphosis of C. onyx depends on the simultaneous presence of both bacterial and diatom communities in biofilms.     

Dietary separation between two blennies and the Pacific gregory in northern Taiwan: evidence from stomach content and stable isotope analyses

Two blennies, Ecsenius lineatus Klausewitz and Ecsenius namiyei (Jordan and Evermann), and a cohabiting territorial damselfish, the Pacific gregory, Stegastes fasciolatus (Ogilby), were collected from shallow reefs in northern Taiwan between September and November 2004, and in October 2005 for stomach content and δ ¹³C and δ ¹⁵N analyses in an effort to study how extensively their food sources overlapped and to delineate the pattern of cohabiting interactions. These analyses showed differences in food use between the Ecsenius blennies and S. fasciolatus. However, there were inconsistencies. Epiphytic algae were their major food items of E. namiyei and E. lineatus. Macroalgae were rarely taken. Nevertheless, δ ¹³C and δ ¹⁵N signatures suggested that E. namiyei and E. lineatus might have assimilated mainly macroalgae-derived detritus instead of epiphytic algae. In contrast, macroalgae were the major food items of S. fasciolatus, followed by epiphytic algae. Differences in both δ ¹³C and ¹⁵N values indicated that for S. fasciolatus, algae (both macroalgae and epiphytic algae) might not be as important as the stomach contents showed. Instead, polychaetes were possibly its major food source. Differences between stomach contents and evidence from the separation of stable isotope signatures between blennies and the Pacific gregory indicate that some of the interspecific interactions derived from exploitative competition may have been alleviated. Moreover, their widespread territory overlap is possibly a sign of mutualism: S. fasciolatus allows territory sharing, while Ecsenius blennies, in return, clean up the algal mat by removing sand and detritus.     

Sex-ratio variation in Soay sheep

We studied the effects of ecological variables on the birth sex ratio of Soay sheep (Ovis aries) lambs on the island of Hirta, in the St Kilda archipelago, Scotland. Both individual- and population-level models were constructed. In the individual-based model, only population size was significantly associated with the sex of a lamb, with the probability of giving birth to a male lamb being positively associated with population size. However, this model explained a very small proportion of the variance in birth sex ratio. A multiple regression analysis of the annual population birth sex ratio also showed a slight increase in the proportion of males born in years following high autumn population density, but this result was not statistically significant. Population growth rate, Julian birthday, litter size, mother's age and weight, and the weather conditions during the gestation and neonatal period did not explain significant variation in the birth sex ratio.     

Temporal overlap of female kin in Columbian ground squirrels (Spermophilus columbianus)

Summary Columbian ground squirrels (Spermophilus columbianus) were live-trapped from 5 to 7 years at three sites in southwestern Alberta, Canada. The two most common adult matrilineal relatives for 2-year-old females were the mother and a 1 year older non-littermate sister. Co-occurrence of female kin depended firstly on size and sexual composition of litters and secondly on age-specific survival and recruitment rates. Adult matrilineal kin frequently coexisted among breeding females of this species, leading us to predict a social system strorgly influenced by nepotism. However, the life history traits of S. columbianus suggest an adult female kin cluster unlike that found for other species of Spermophilus in which littermate sisters are common. If availability of adult female kin influences kin-differential behaviour, then female S. columbianus should favour mothers, daughters and non-ittermate sisters.     

叶酸、L-苯丙氨酸、维生素E废水治理方案研究

根据叶酸、L-苯丙氨酸、维生素E废水水质酸度高、色度深、盐度高、有机物含量高、可生化降解性差的特点,选择了"化学中和十兼氧/好氧PACT生化处理工艺".运行结果表明,经该工艺处理后,废水中的COD、BOD5、色度、PH等指标均能达标排放.     

Removal of selected natural and synthetic estrogenic compounds in a Canadian full-scale municipal wastewater treatment plant.

The effect of a full-scale municipal wastewater treatment plant (WWTP) and each of the treatment units within the stream on the removal of endocrine-disrupting compounds was evaluated by tracking 17-beta-estradiol (E2), estrone (E1), and 17-alpha-ethinylestradiol (EE2). The overall performance of the WWTP compared well with other plants, as 90.5% removal of E1+E2 and 74.9% removal of EE2 were observed. A larger fraction of EE2 entered the plant in particulate form than E1 and E2, while a lower fraction of EE2 left the plant in particulate form than soluble form. The activated sludge units reduced the concentration of E1+E2 and EE2 in the liquid phase by 88.2% and 44.6%, respectively. The UV treatment process did not reduce the amount of estrogens. The aqueous phase of the tertiary lagoon solids contained higher levels of estrogens compared with the lagoon influent.