应用选择器抑制污泥膨胀的20年实践

选择器是在控制丝状菌膨胀实践中孕育而生。丝状菌一般在基质浓度较低的条件下生长，基质浓度较高时菌胶团将要代替丝状菌。根据这一理论，选择器在２０年间逐渐地被开发出来。本文列举了一些成功例子的设计参数和具体结构，并指出了选择器的局限性，即它不能解决所有由丝状菌引起的问题。     

Territory and group sizes in Eurasian beavers (Castor fiber): echoes of settlement and reproduction?

According to current theories of territoriality, an animal is expected to defend the smallest area that can provide resources for maximisation of reproduction, known as the economically defendable area. In group territorial species however, the strategies behind resource defence are likely to be more complex with corporate territoriality, cooperative breeding, delayed dispersal and intra-group competition all potentially playing a role. Here we examined group territoriality in a social herbivorous rodent, the Eurasian beaver Castor fiber. Beavers in our study do not inhabit economically defendable territories. Instead the sequence of arrival of pairs into unoccupied areas seems to play a more important role in determining the size of the territory, whereas group size is determined by past reproductive success. We argue that the settlement pattern and reproductive history have a lasting impact in the territorial system of beavers due to a combination of the low adult mortality, high dispersal costs, and avoidance of resource depletion.R.D. Campbell and F. Rosell contributed equally to this work     

Optimal maternal investment in the dung beetle<Emphasis Type="Italic"> Onthophagus taurus</Emphasis>?

Optimal investment theory is based on the assumption that the proximate constraint acting on parental investment is resource based. A trade-off between per offspring investment and total investment seems intuitive. Consequently, a parents investment strategy is expected to represent a trade-off between the benefits of investment for current offspring and the costs to future reproduction for parents. In this study, we provide clear evidence that the costs and benefits of maternal provisioning in the dung beetle Onthophagus taurus influence the amount of provisions provided by the mother. Horse dung is typically of a higher nutritional value than cow dung and females were shown to provide 20% less dung to offspring when provisioning with horse dung. By reducing their investment per offspring and exhibiting a clear preference to provision offspring with horse dung, females were able to produce significantly more offspring. Females provisioning with horse dung received greater fitness returns per unit of investment and experienced lower provisioning costs, in terms of the minimum amount of dung required to produce a surviving offspring, than females provisioning with cow dung. Females provisioning in soil of low moisture content were found to have higher tunneling costs than those provisioning in soil of high moisture content, while the fitness returns per unit of investment did not differ. We adopted a marginal value theorem (MVT) approach to calculate the theoretical optimal level of investment for each dung type and for each soil moisture. Predicted levels of provisioning were lower for horse dung than for cow dung and for moist soil than for dry soil. Therefore, the results of this study are in qualitative agreement with MVT predictions and provide empirical support for the proposal that females can adaptively adjust their level of investment in response to resource and/or habitat quality. However, the theoretically predicted optimal investment yielded a poor quantitative fit with our observed levels of investment, with females providing over twice the investment predicted by the MVT approach. We suggest that this difference may reflect either our inability in directly quantifying all the necessary costs and benefits of investment in O. taurus and/or the applicability of the underlying assumptions of MVT.Communicated by D. Gwynne     

Weapon size versus body size as a predictor of winning in fights between shore crabs, Carcinus maenas (L.)

Relative body size (carapace width) and weapon size (chela length) were used as indicators of resource holding potential (RHP) in the agonistic behaviour of male shore crabs, Carcinus maenas (L.). Weapon size was found to be a more reliable predictor of the outcome of pairwise fights than body size. Crabs with longer chelae than their opponents were more likely to win fights than crabs with relatively larger bodies. Body size had less influence on the outcome of fights. Relative body and weapon size did not influence initiation of contests but did affect the likelihood of winning; however, this was significant only for weapon size. Winning crabs had heavier claws with greater surface area than losing crabs. There was no relationship between relative size and fight duration. The frequency of cheliped display increased with chela length and win- ners performed significantly more displays than losers. Received: 5 February 1997 / Accepted after revision: 20 May 1997     

高温好氧消化污泥对生物除磷的强化作用初探

由于高温好氧消化(TAD)后的污泥中常含有一定浓度的挥发性脂肪酸(VFA),为考察其对生物除磷系统的影响,通过将TAD污泥上清液与乙酸钠进行磷去除作用的对比试验。表明在厌氧条件下,加入TAD污泥的上清液,会使大量的P释放,磷释放规律及其释放速度均与乙酸钠造成的磷释放相当,因此,可以考虑将高温好氧消化污泥或上清液回流作为一种补充碳源,以强化生物除磷系统的除磷效果。但实际应用中,还要考虑到VFA降解以及回流污泥中的氮磷负荷,而且长期回流还需要进一步的试验验证。     

推进城市再生水源热泵供热，实现节能减排新突破——沈阳市再生水源热泵供热进展

再生水源热泵供热是指利用热泵技术提取再生水中的低品位热能为建筑物供热。本文以沈阳市系统推进该项节能减排技术为例,阐述了其对国内城市推广再生水源热泵技术供热的重大示范意义,并提出了进一步发展再生水源热泵供热的对策建议。     

城市生态示范区建设成效层次模糊综合评价研究

将层次模糊综合评价模型应用于生态示范区指标体系,采用专家调查法构造判断矩阵,确定了指标权重,并对生态示范区建设指标体系进行分级,评价了长沙市开福区生态示范区建设的成效。结果表明,长沙市开福区自开展生态示范区建设以来,在社会、经济和生态环境领域都取得了明显进步,2002年至2003年时间段的成效尤为显著。     

两组矿化垃圾处理浓缩液效果对比

采用柱回灌法进行实验,对两组矿化垃圾处理浓缩液效果对比。结果表明：两组矿化垃圾对浓缩液均有一定的处理效果,矿化垃圾填埋年限越长对浓缩液处理效果越好。     

如何提高县级环境监测数据的利用率

目前环境监测任务日益加重,监测数据日益增多,但是很多监测站数据的利用率和可利用性并没有随之提高。很多监测部门都存在盲目地攀比数据的数量,将监测数据的数量作为工作量或成绩的见证,而从来不提监测数据的可利用性和利用率。在此就目前存在的一些问题及如何提高县级监测数据的利用率进行了探讨,提出了通过优化监测工作和规范监测数据等来提高监测数据的可利用性和利用率,从而为县级环境监测站的监测工作提供借鉴。     

新汶矿区循环经济发展模式浅析

对于资源趋于枯竭、生产成本渐高、生态环境恶化的矿区来讲,发展循环经济、打造资源节约型矿区是解决这些问题的有效手段。通过对新矿集团发展循环经济的理念、实践、总结和展望的分析研究,总结了新矿集团循环经济发展模式,对于煤炭企业发展循环经济提供借鉴,为全力打造资源节约型矿区提供参考。