Information processing in models for density-dependent emigration: A comparison

Density-dependent emigration has been recognized as a fitness enhancing strategy. Yet, especially in the modelling literature there is no consensus about how density-dependent emigration should quantitatively be incorporated into metapopulation models. In this paper we compare the performance of five different dispersal strategies (defined by the functional link between density and emigration probability). Four of these strategies are based on published functional relationships between local population density and emigration probability, one assumes density-independent dispersal. We use individual-based simulations of time-discrete metapopulation dynamics and conduct evolution experiments for a broad range of values for dispersal mortality and environmental stochasticity. For each set of these conditions we analyze the evolution of emigration rates in ‘monoculture experiments’ (with only one type of dispersal strategy used by all individuals in the metapopulation) as well as in selection experiments that allow a pair-wise comparison of the performance of each functional type. We find that a single-parameter ‘asymptotic threshold’ strategy - derived from the marginal value theorem - with a decelerating increase of emigration rate with increasing population density, out-competes any other strategy, i.e. density-independent emigration, a ‘linear threshold’ strategy and a flexible three-parameter strategy. Only when environmental conditions select for extremely high emigration probabilities (close to one), strategies may perform approximately equally. A simple threshold strategy derived for the case of continuous population growth performs even worse than the density-independent strategy. As the functional type of the dispersal function implemented in metapopulation models may severely affect predictions concerning the survival of populations, range expansion, or community changes we clearly recommend to carefully select adequate functions to model density-dependent dispersal.     

社区大气污染物排放总量控制研究

为了寻求社区大气污染物排放总量控制的方法和可行途径,在污染源调查的基础上,以城市多源大气扩散模式（ＩＳＣＳＴ）为建模工具,采用以“总量控制线性方程组”作为约束条件的线性规划方法,对控制北京市西城区大气污染物排放总量达到环境目标的几种方案作了分析,如燃烧优质煤和天然气等。同时,给出了总量控制管理信息系统的结构图和功能图。     

煤矿安全生产调度指挥信息系统及其应用

介绍了煤矿安全生产指挥信息系统的由来、组成、特点、功能及其效果与前景。该系统以对煤矿安全生产指挥决策信息支持为目的 ,集矿山安全、工况监测及生产调度信息的采集、实时传输处理、图像 /图形显示、图形和数据存储管理及输出为一体 ,已在平煤集团公司多个矿区安装使用 ,产生了较好的经济效益及社会效益。     

信息融合技术在采空区安全评价中的应用研究

信息融合技术充分利用多源信息的互补性、综合性,可以极大地提高评价指标信息的质量和可信度。本文利用信息融合的理论和方法,建立了煤矿采空区安全性评价的数学模型,给出了基于D-S证据理论的多源信息分析、处理、分配、融合等信息处理步骤,结合GIS的强大图形处理能力,快速生成成果图。通过对某采空区安全预测的实际应用,获得了满意的效果,说明所建模型的有效性和实用性。     

建筑施工现场安全信息定置管理技术研究

建筑施工现场是一个动态的、复杂的的场所,是人流、物流、信息流交汇的地点,管理难度大,发生意外安全事件和安全事故多。为了解决这个难题,本文针对目前建筑工程施工现场的特点,提出了用安全信息定置管理技术来解决建筑施工安全难题的方法。通过现场直观、形象、通俗易懂的看板和现场的安全信息,使现场操作人员通过视觉很容易地从管理看板上和现场的各种标识上获取有关安全操作的各种信息和管理者的要求和意图,从而实现操作者的自主管理、自我控制,实现安全施工的目的。同时介绍了用定置管理原理的科学定置技术,从建筑工程施工现场安全信息管理的收集、加工、设计、应用的方法。建筑施工现场安全信息定置管理技术的推广,将加速建筑安装企业及建筑施工现场的标准化安全管理的实现,真正实现预防为主、自主管理为主、持续改进的安全管理模式。值得在建筑施工现场推广。     

环境信息分类编码标准化

本文论述了我国环境信息分类编码标准化工作及其重要意义,着重探讨了信息分类的方法,提出了对我国环境信息分类编码工作的意见。      

信息不对称对发展循环经济的不利影响及对策分析

信息不对称理论在经济活动中的作用越来越大。本文结合昆山市发展循环经济的实践 ,分析了发展循环经济过程中信息不对称的主要表现 ,揭示了信息不对称对发展循环经济的负面影响 ,进而论证了大力发展环境信息服务业是解决环境信息不对称的最佳方式 ,是发展循环经济、生态工业、生态农业等环保型事业的重要保障     

Network calculations and ascendency based on eco-exergy

Ascendency is an index of activity and organization in living systems calculated in terms of flows. The concern here is with how that quantity behaves when the flows in question are measured in terms of eco-exergy. The storage of eco-exergy has served as a goal function in assessing parameter values for structurally dynamic models, but network magnitudes and topologies can change in response to significant changes in the forcing functions. As storages are relatively insensitive to such changes, it is advisable in such cases to explore how changes in a flow variable, like ascendency, might capture network adaptations. It happens that changes in ascendency calculated in terms of flows of simple energy are small in comparison to corresponding variations in the storages of eco-exergy. But when ascendency is reckoned in terms of flows of eco-exergy, its changes in response to network changes are more comparable to those in the storages. Ascendency seems to be more sensitive to changes in flow topology, however, so that a combination of eco-exergy storage and eco-exergy ascendency would probably be most appropriate for situations where changes in flow topology are significant.     

生态系统服务内涵、价值评估与GIS表达

生态系统服务价值评估是当前生态经济学领域的研究热点,为解决生态系统之于人类的重要性提供了量化的参考,也是生态补偿机制建立的重要依据.近5年国际上SCI论文发表数量以年均40%速度增长,我国研究起步于上世纪90年代末,十年来发展迅速,从对国外研究的简单模仿逐渐转向对评估模型参数的修正及对技术方法的适应性集成与发展.生态系统服务的内涵研究不断推进,在阐释“自然组分-生态过程-生态功能-生态服务.获得利益”关系上呈现多种观点,相应地提出了不同的价值评估指标体系;生态系统服务价值评估以瞬时静态为主,动态评估略显不足;研究对象从大尺度和单一生态系统逐渐转向中尺度区域,评估结果表现形式从单一数值化向基于GIS的空间表达发展.在回顾全球范围生态系统服务评估研究成果的基础上,从研究区域分布与学科特点、内涵及分类、评估方法和GIS技术应用等四大方面进行归纳分析,并从生态系统管理和决策支持需求的角度,指出生态系统评估研究已取得显著进展,但有关生态系统服务的内涵与分类、生态系统服务价值的动态评估及GIS技术的应用研究仍待深入.     

Informative content of multiple plumage-coloured traits in female and male European Rollers

Animals may assess the quality of other individuals by using information that different ornaments may provide. The European Roller (Coracias garrulus) is a socially monogamous species in which males and females display highly conspicuous plumage colouration. According to the mutual selection hypothesis, we predicted that, in this species, plumage coloration could signal individual quality in both sexes because both female and male rollers invest a considerable amount of time caring for their offspring. We used spectrophotometric measurements to investigate the information content of multiple plumage colour traits. We found that the roller is actually a sexually dimorphic and dichromatic species. Different plumage colours from different origins were correlated within individual. Head and back brightness correlated with body condition in both sexes, and in males, head brightness correlated with the number of fledglings in successful nests, while head green-yellow saturation correlated with parental provisioning. Meanwhile, in females, back brightness was related to the number of fledglings in successful nests and to parental provisioning rate. In addition, there was a positive assortative mating in relation to weight, body condition, head green-yellow saturation and back brightness. Finally, we found a positive correlation between parent and offspring coloration. Altogether, these results suggest that multiple colour traits may act as quality indicators in the roller and that they may be used by the two sexes to assess potential mate quality.