Unattractiveness of mated females to males in the parasitoid wasp Spalangia endius

Despite common stereotypes, males are not always indiscriminate and eager when it comes to mating. In the parasitoid wasp Spalangia endius, the initial response of males to females was almost always one of apparent excitement; however, this was followed by a clear preference for virgin females over mated females in both no-choice and choice situations. The no-choice data were collected from videotapes of male-female pairs of all possible combinations of mated and virgin individuals. Neither female nor male mating status had a significant effect on likelihood of, or time until, contact or male courtship fanning. However, a males first retreat was sooner when the female was mated than when she was virgin; mated males exhibited their first retreat sooner than did virgin males; and mated females were less likely to be mounted than were virgin females. In addition to the videotapes, male-choice experiments were performed. When given a choice of a virgin and a mated female, both virgin and mated males were more likely to mount and copulate with the virgin. The difference in response to virgin versus mated females seemed to be less in virgin males than in mated males, perhaps due to virgin males greater eagerness to mate: when a virgin male and a mated male were presented with a dead virgin female, the virgin male was usually the first to respond to the female. That males preferentially retreated from and avoided mounting mated females appears to be adaptive given that mated females rarely copulated.Communicated by N. Wedell     

Species Review of Amphibian Extinction Risks in Madagascar: Conclusions from the Global Amphibian Assessment

Abstract:  We assessed the extinction risks of Malagasy amphibians by evaluating their distribution, occurrence in protected areas, population trends, habitat quality, and prevalence in commercial trade. We estimated and mapped the distribution of each of the 220 described Malagasy species and applied, for the first time, the IUCN Red List categories and criteria to all species described at the time of the assessment. Nine species were categorized as critically endangered, 21 as endangered, and 25 as vulnerable. The most threatened species occur on the High Plateau and/or have been subjected to overcollection for the pet trade, but restricted extent of occurrence and ongoing habitat destruction were identified as the most important factors influencing extinction threats. The two areas with the majority of threatened species were the northern Tsaratanana-Marojejy-Masoala highlands and the southeastern Anosy Mountains. The current system of protected areas includes 82% of the threatened amphibian species. Of the critically endangered species, 6 did not occur in any protected area. For conservation of these species we recommend the creation of a reserve for the species of the Mantella aurantiaca group, the inclusion of two Scaphiophryne species in the Convention on the International Trade in Endangered Species Appendix II, and the suspension of commercial collecting for Mantella cowani . Field surveys during the last 15 years reveal no pervasive extinction of Malagasy amphibians resulting from disease or other agents, as has been reported in some other areas of the world.     

徐州市区环境空气中TVOC污染现状及变化规律

2003年1-12月使用光离子化检测仪，对徐州市环境空气中的TVOC进行检测，监测结果显示：徐州市区环境空气中的TVOC浓度值1月份最高；其次为6月份；年平均值为82μL/m^3；交通干道两旁污染最严重。     

低负荷运行对城市污水生物除磷的影响

针对目前国内较多的城市污水处理厂长期处于低负荷运转的状态，进行了现场生产性与静态模型的试验研究。结果表明，长期低负荷运行是导致生物除磷效率下降的主要原因。长期低负荷运行使聚磷菌微生物细胞内储存物质（PHB、Glycogen、poly-P等）含量下降，使生物除磷能力丧失。为了保证生物脱氮除磷处理系统的除磷效率，可通过调节生化反应容积、控制好氧区的曝气等手段，使处理系统的负荷控制在适合的范围内。     

美国自来水行业消毒现状和展望

为了了解美国自来水行业消毒现状,在查阅了相关外文文献的基础上,对相关资料进行总结和分析.结果表明:氯气虽然仍是最广泛使用的消毒方式,但出于人们对健康安全的关注和许多饮用水法规的实施,使用氯气的水厂数量在不断减少.     

How Community Action, Science and Common Sense can Work Together to Develop an Alternative Way to Combat Desertification

The Spitzkoppe Community Campsite in western Namibia lies in an area with very limited water resources. Water scarcity places a constraint on community income generation and development opportunities. The existing water resources are overexploited and to ensure future water security, the community must take sustainable water management into consideration in their daily lives and business ventures, including tourism. This has been successfully achieved at the Spitzkoppe Community Campsite through a combination of high community motivation, organisation and action, the involvement of researchers and trainers in water resource management and support from developers. The most appropriate water management solutions were found through ongoing practical testing of different strategies and technologies over two years. This paper presents a case study of a community-based tourist camp at Spitzkoppe and traces the community’s progress towards developing an alternative way to combat desertification and a potentially lucrative tourist business.     

济南市重点污染源烟气在线监测控制系统的开发研究

介绍了济南市重点污染源烟气在线监测控制系统的开发研究工作。重点分析了被测锅炉的选取和监测点位的优选,监测项目和在线监测仪器优选,数据传输网络和监测控制软件的开发研究,烟气在线监测系统的验收方案等四个方面。对烟气在线监测工作的开展有较强的示范意义。     

A comparison of fixed-site and non-fixed-site approaches for species protection

The efficacy of simultaneously advancing two distinct conceptual designs (referred to here as fixed-site and non-fixed-site) for species conservation and protection is addressed. In the literature, numerous models can be found that typically stem from a particular design, but rarely are comparisons made between approaches. This paper presents a more integrated optimization framework that models landowner behavior and species viabilities at a landscape scale. Regional demand for resource extraction is used as the economic driver, a variant of simulated annealing is used to solve the model under different species protection approaches, and a detailed species population simulator is utilized to measure biological responses. When directly comparing the outcomes of different species protection strategies from a case study in Oregon (USA), it was found that neither approach was universally superior in terms of financial value or degree of protection for two late seral forest dependent species.     

优化布点中模式计算结合历史数据估算的分析方法及研究

随着城市建设发展,城市建成区不断扩大,在空气质量监测中,旧的城区监测点位很难准确反映新的区域内的空气质量时空变化,文章尝试在新的发展区建立一个数学模型,预测新区域内有代表性的某一特征监测点浓度,与旧城区监测点位优选点共同构成整个区域的空气质量监测系统。