Need for multiscale planning for conservation of urban bats

For over a century there have been continual efforts to incorporate nature into urban planning. These efforts (i.e., urban reconciliation) aim to manage and create habitats that support biodiversity within cities. Given that species select habitat at different spatial scales, understanding the scale at which urban species respond to their environment is critical to the success of urban reconciliation efforts. We assessed species–habitat relationships for common bat species at 50‐m, 500‐m, and 1 km spatial scales in the Chicago (U.S.A.) metropolitan area and predicted bat activity across the greater Chicago region. Habitat characteristics across all measured scales were important predictors of silver‐haired bat (Lasionycteris noctivagans) and eastern red bat (Lasiurus borealis) activity, and big brown bat (Eptesicus fuscus) activity was significantly lower at urban sites relative to rural sites. Open vegetation had a negative effect on silver‐haired bat activity at the 50‐m scale but a positive effect at the 500‐m scale, indicating potential shifts in the relative importance of some habitat characteristics at different scales. These results demonstrate that localized effects may be constrained by broader spatial patterns. Our findings highlight the importance of considering scale in urban reconciliation efforts and our landscape predictions provide information that can help prioritize urban conservation work.     

阻尼隔声板在噪声控制工程上的应用

对隔声材料的隔声功能进行了分析,根据两种以上不同质的复合材料可避开各自的阻隔波谷,能更有效地提高阻隔宽频噪声的总体性能的声学原理,提出了安装有阻尼层的隔声板,可有效提高隔声板的隔声量。     

Inferring the nature of anthropogenic threats from long‐term abundance records

Diagnosing the processes that threaten species persistence is critical for recovery planning and risk forecasting. Dominant threats are typically inferred by experts on the basis of a patchwork of informal methods. Transparent, quantitative diagnostic tools would contribute much‐needed consistency, objectivity, and rigor to the process of diagnosing anthropogenic threats. Long‐term census records, available for an increasingly large and diverse set of taxa, may exhibit characteristic signatures of specific threatening processes and thereby provide information for threat diagnosis. We developed a flexible Bayesian framework for diagnosing threats on the basis of long‐term census records and diverse ancillary sources of information. We tested this framework with simulated data from artificial populations subjected to varying degrees of exploitation and habitat loss and several real‐world abundance time series for which threatening processes are relatively well understood: bluefin tuna (Thunnus maccoyii) and Atlantic cod (Gadus morhua) (exploitation) and Red Grouse (Lagopus lagopus scotica) and Eurasian Skylark (Alauda arvensis) (habitat loss). Our method correctly identified the process driving population decline for over 90% of time series simulated under moderate to severe threat scenarios. Successful identification of threats approached 100% for severe exploitation and habitat loss scenarios. Our method identified threats less successfully when threatening processes were weak and when populations were simultaneously affected by multiple threats. Our method selected the presumed true threat model for all real‐world case studies, although results were somewhat ambiguous in the case of the Eurasian Skylark. In the latter case, incorporation of an ancillary source of information (records of land‐use change) increased the weight assigned to the presumed true model from 70% to 92%, illustrating the value of the proposed framework in bringing diverse sources of information into a common rigorous framework. Ultimately, our framework may greatly assist conservation organizations in documenting threatening processes and planning species recovery. Inferencia la Naturaleza de las Amenazas Antropogénicas para los Registros de Abundancia a Largo Plazo     

乌鲁木齐河源冰川径流中总可]溶性固体和悬浮颗粒物的特征及影响因素分析

通过对天山乌鲁木齐河源1号冰川进行连续4年(2004-2007年)冰川融水径流观测取样,应用数理统计、不同参数和模型比较等方法,对径流中总可溶性固体(TDS)和悬浮颗粒物(SPM)的特征及影响因素进行分析研究.结果表明,总体上冰川区径流中TDS和SPM与其它区域相比浓度较低,且随时间变化明显.TDS年际变化较小,年内变...     

含铊硫铁矿生产硫酸过程中铊的排放特性

通过焙烧实验探讨了含铊硫铁矿生产硫酸过程中铊的排放特性.结果表明,硫铁矿焙烧过程中,铊排放与焙烧温度、停留时间、焙烧气氛、硫铁矿的粒度等因素有关.不同的温度条件下,铊排放率不同,这主要是与矿石中铊的赋存形态有关;实验条件下,550℃—950℃是Tl排放的主要阶段,Tl排放量约占硫铁矿中总Tl的33.9%.Tl的排放率随...     

Combining state and transition models with dynamic Bayesian networks

Bashari et al. (2009) propose combining state and transition models (STMs) with Bayesian networks for decision support tools where the focus is on modelling the system dynamics. There is already an extension of Bayesian networks - so-called dynamic Bayesian networks (DBNs) - for explicitly modelling systems that change over time, that has also been applied in ecological modelling. In this paper we propose a combination of STMs and DBNs that overcome some of the limitations of Bashari et al.’s approach including providing an explicit representation of the next state, while retaining its advantages, such an the explicit representation of transitions. We then show that the new model can be applied iteratively to predict into the future consistently with different time frames. We use Bashari et al.’s rangeland management problem as an illustrative case study. We present a comparative complexity analysis of the different approaches, based on the structure inherent in the problem being modelled. This analysis showed that any models that explicitly represent all the transitions only remain tractable when there are natural constraints in the domain. Thus we recommend modellers should analyse these aspects of their problem before deciding whether to use the framework.     

硝化反硝化过程中N_2O释放影响因素

结合N2O的产生机理,分析温度、含水率、NO2--N和底物质量浓度、pH和碱度、O2以及基质等因素对N2O释放的影响,试图探讨不同因素对N2O释放的影响规律,以期对生化过程中N2O的控制提供理论和技术支持。N2O的释放是温度、含水率、C/N、O2浓度、反应底物质量浓度、基质以及传输过程交互作用的结果。含水率、C/N、基质及温度等可通过不同途径影响溶解氧的质量浓度而影响N2O释放量;pH、NO2--N、NH3-N及温度等通过影响硝化、反硝化细菌的活性或对各阶段酶的抑制作用而影响N2O释放;土壤利用类型、植被种类、污水脱氮过程各参数等,会间接影响硝化和反硝化过程从而影响N2O的释放。     

铁路噪声影响特点与评价方法研究

针对山东省境内一主要铁路路段的铁路噪声,布设了不同类型的多个点位进行了测量.应用大量的实测数据,对铁路噪声的变化规律及影响特点进行了分析研究.铁路噪声的Lmax对铁路两侧环境的影响明显大于Leq.     

基于贝叶斯网络的突发事件影响度研究

不确定性的知识表示和推理是突发事件影响度评估中需要解决的重要问题。针对突发事件评估信息的多样性、不确定性及模糊性,利用贝叶斯网络易于进行不确定性推理的优点,提出了采用贝叶斯网络对突发事件影响度进行评价,建立了评价模型,给出了推理决策方法,并且对该方法进行了算例分析。算例表明,基于贝叶斯网络的突发事件影响度评价模型能够提高评估的准确度及对突发事件的响应能力。     

有机蒸气滤毒盒防护时间的研究概况

滤毒盒防护时间是使用者最为关心的问题,也是国内外学者的研究热点。本文系统地综述了国内外对有机蒸气滤毒盒防护时间的研究进展,分析了各种因素对防护时间的影响。