论基于多元联系数的集对分析评价模型

集对分析是一种处理不确定性问题的系统分析方法,利用该方法对系统危险性进行了评价,指出了多元联系数集对分析方法在系统危险性评价中存在的不足,探讨了其应用条件,提出了与系统级别特征值相结合来判断系统危险性级别的方法,并给出了多元联系数集对分析的评价程序。实例表明,该方法科学、可行,为系统危险性评价提供了一种新的思路。     

Integrating intraseasonal grassland dynamics in cross-scale distribution modeling to support waterbird recovery plans

Despite much discussion about the utility of remote sensing for effective conservation, the inclusion of these technologies in species recovery plans remains largely anecdotal. We developed a modeling approach for the integration of local, spatially measured ecosystem functional dynamics into a species distribution modeling (SDM) framework in which other ecologically relevant factors are modeled separately at broad scales. To illustrate the approach, we incorporated intraseasonal water-vegetation dynamics into a cross-scale SDM for the Common Snipe (Gallinago gallinago), which is highly dependent on water and vegetation dynamics. The Common Snipe is an Iberian grassland waterbird characteristic of European agricultural meadows and a member of one of the most threatened bird guilds. The intraseasonal dynamics of water content of vegetation were measured using the standard deviation of the normalized difference water index time series computed from bimonthly images of the Sentinel-2 satellite. The recovery plan for the Common Snipe in Galicia (northwestern Iberian Peninsula) provided an opportunity to apply our modeling framework. Model accuracy in predicting the species’ distribution at a regional scale (resulting from integration of downscaled climate projections with regional habitat–topographic suitability models) was very high (area under the curve [AUC] of 0.981 and Boyce's index of 0.971). Local water-vegetation dynamic models, based exclusively on Sentinel-2 imagery, were good predictors (AUC of 0.849 and Boyce's index of 0.976). The predictive power improved (AUC of 0.92 and Boyce's index of 0.98) when local model predictions were restricted to areas identified by the continental and regional models as priorities for conservation. Our models also performed well (AUC of 0.90 and Boyce's index of 0.93) when projected to updated water-vegetation conditions. Our modeling framework enabled incorporation of key ecosystem processes closely related to water and carbon cycles while accounting for other factors ecologically relevant to endangered grassland waterbirds across different scales, allowed identification of priority areas for conservation, and provided an opportunity for cost-effective recovery planning by monitoring management effectiveness from space.     

西宁市浅层地下水化学特征及形成机制

地下水是西部干旱地区重要的供水水源,随着西部大开发战略的深入,工业化和城市化发展加大了西宁市对地下水资源量的需求,不合理的开发利用已引起地下水环境发生变化,探明地下水化学演化特征及形成机制,对防止其恶化,确保可持续利用至关重要.运用水化学和多元统计技术相结合的方法,分析了西宁市地下水化学特征,探讨了地下水的形成机制和不同因子的影响程度.结果表明,西宁市浅层地下水化学类型多达36种,以HCO₃-Ca(Mg)(占比60.00%)和HCO₃·SO₄-Ca(Mg)(占比11.81%)为主,草地、林地和裸地中地下水化学类型5～6种,建设用地和耕地中地下水化学类型复杂,多达21种,表明受到人类活动影响较强.研究区地下水化学演化过程主要受岩石风化溶滤、蒸发结晶和阳离子交换作用综合影响,主要控制因素分别是水-岩相互作用(贡献率为27.56%)、工业废水排放(贡献率为16.16%)、酸碱环境(贡献率为16.00%)、化肥、农药的过量施用(贡献率为13.11%)和生活污水(贡献率为8.82%).针对西宁市地下水化学特征及其人类活动影响,提出...     

南昌市浅层地下水水质评价及监测指标优化

地下水环境监测过程中保证地下水水质评价代表性的同时尽量优化监测指标数量,对地下水环境管理具有重要的意义.选取南昌市地区2014年和2019年浅层地下水监测数据,运用统计分析、 Piper三线图和熵权水质指数(EWQI)分析水化学特征及水质变化,并耦合逐步多元线性回归分析构建基于水质评价的关键指标优化方法,评估此方法应用的可行性.结果表明,南昌市地下水2014年和2019年水化学类型主要为HCO₃-Ca型;pH值、 NO^-₃、 I^-、 Fe和Mn等5项超标指标是水质变化的主要影响因子;2019年水质状况总体上高于2014年,基本为“中等”水质,二者EWQI平均值分别为53.72和82.34;基于关键指标优化方法构建的最优模型EWQI_min-4能够较好地代表实际的EWQI,关键指标包括Mn、 NO^-₃、 TH、 Fe、 pH值和I^-,其决定系数(R²)和百分比误差(PE)值分别为0.865和10...     

湿地生态系统服务功能评估研究进展

介绍了湿地生态系统服务功能评估发展历程和生态系统服务价值评估的理论基础,对湿地生态服务功能评估的流程、方法、指标体系建立给出了参考范例,并探讨了生态服务价值评估在方法和技术上需要改进的几个方面,主要包括评价方法的统一、生态过程价值的理解、计量参数修正、标准和体系的选择、对生态服务功能状态好坏分级评估。阐述了生态系统服务价值评估还存在某些问题及有待今后发展的理论和方法来改进和完善的途径。     

城市绿色空间综合评价指标体系构建及应用

为科学合理地评价城市绿色空间的生态景观效益、社会效益以及经济效益,建立了一套较为科学、全面的评价指标体系,其包括基本数量特征、景观格局、社会管理因素和生态功能等4个Ⅱ级指标以及16个Ⅲ级指标,并依次对北京城市绿色空间现状进行了综合评价。结果表明:北京市绿色空间综合评价指标值为0.67,处于第Ⅱ级下游,表明北京城市绿色空间面积适当、结构较合理,生态功能发挥良好,总体建设较好;但同时也存在景观连接度较差、可达性不好、居民满意度不高等问题,从而影响了其生态功能和社会功能的有效发挥。     

我国城市轨道交通规划环境影响评价指标体系初探

概述了我国城市轨道交通规划与建设及其规划环评工作现状。在对10个城市轨道交通规划环评指标体系分析的基础上,总结了评价指标体系在结构层次和内容方面存在的问题,并提出了解决问题的关键点。建立了基于交通环境承载力的城市轨道交通规划环评指标体系,并展望了其在城市轨道交通规划环评中的应用前景。     

陕西省生态城市建设评价指标体系

从陕西省各城市的社会状况和地域情况入手,选择和构建了适合陕西省自身情况的生态城市指标评价体系,并进一步建立了描述城市生态系统发展状况的标准化处理方法和计算方法,最后使用以上方法,对陕西省2008年的生态城市建设进行综合分析和评价。结果表明:陕西省10个城市的生态城市建设基本可以分为3类,其中西安等3个城市生态建设水平较高;铜川市等5个城市生态建设水平一般;延安市等2个城市生态城市建设水平较低。各个城市都应该依照自身情况明确生态建设的发展方向,制定生态建设方案,大力开展城市生态建设,从而使整个陕西省生态实现一体化发展。     

Trophic field overlap: A new approach to quantify keystone species

It is a current challenge to better understand the relative importance of species in ecosystems, and the network perspective is able to offer quantitative tools for this. It is plausible to assume, in general, that well-linked species, being key interactors, are also more important for the community. Recently a number of methods have been suggested for quantifying the network position of species in ecological networks (like the topological importance metric, TI). Most of them are based on node centrality indices and it may happen that the two most important species in a food web have very similar interaction structure and they can essentially replace each other if one becomes extinct. For conservation considerations it is a challenge to identify species that are richly connected and, at the same time, have a relatively unique and irreplaceable interaction pattern. We present a new method and illustrate our approach by using the Kuosheng Bay trophic network in Taiwan. The new method is based on the interaction matrix, where the strength of the interaction between nodes i and j depends only on topology. By defining a threshold separating weak and strong interactors, we define the effective range of interactions for each graph node. If the overlaps between pairs of these ranges are quantified, we gain a metric expressing how unique is the interaction pattern of a focal node (TO). The combination of centrality (TI) and uniqueness (TO) is called topological functionality (TF). We compare the nodal importance rank provided by this metric to others based on a variety of centrality measures. The main conclusion is that shrimps seem to have the most unique interaction pattern despite that their structural importance has been underestimated by all conventional centrality indices. Also, our network analysis suggests that fisheries disturb the ecosystem in a more critical network position than the impingement by the local power plant.     

基于层次分析法的矿井煤自燃危险性模糊评价

为了能够客观、科学的对煤矿开采过程中煤自燃火灾进行有效的预防,综合运用系统工程理论、层次分析法和模糊数学方法建立了煤自燃的危险性综合评价模型。从"人-机-环-管"系统原理角度出发,建立了多层次的煤自燃危险性评价指标体系,并采用层次法对各层次评价指标的权重进行了计算,确定了5类判断指标用于评价煤自燃的危险等级。并在实践中进行应用,评价结果和煤矿实际开采过程中煤自燃发生情况基本吻合,表明了该模型是合理可行的,能够实现对矿井煤自燃危险性进行评价。