私人参与公共环境服务供给的路径选择

由于环境服务的大部分内容具有公共物品属性,所以在我国长期以来主要由政府负责供给,对财政支出造成巨大的压力.在研究西方私人供给公共物品的理论的基础上,结合我国的实际情况,为我国私人参与公共环境服务供给提供现实的路径选择.     

循环加荷条件下饱和砂土液化细观数值模拟

利用离散单元法中的二维颗粒流方法(particle flow code in 2-dimension,PFC2D),通过对双轴数值试样施加循环等幅应变且控制加荷过程中试样体积(面积)不变的方法,模拟了循环加荷条件下饱和砂土的液化特性。在得到试样液化宏观力学响应的同时,分析了液化过程中内部平均接触数的变化规律。进一步研究了应变幅值、围压对数值试样液化特性的影响,并与室内试验规律进行了对比。结果表明,数值模拟能够定性地反映饱和砂土振动液化的一般规律,数值模拟得到的应变幅值、围压对试样抗液化强度的影响规律符合实际砂土室内试验规律。     

Longitudinal Plankton Dynamics in the Rivers Rhine and Elbe

We compared the longitudinal plankton development in the two large rivers Rhine and Elbe by means of four Lagrangian sampling campaigns performed within the time span 2009–2011. The campaigns revealed low chlorophyll concentrations in the Rhine along a long river stretch (Rhine‐km 170 to 854) with maximum values below 5 µg L^?1 in 2010. In contrast, the Elbe (Elbe‐km 4 to 582) showed high and longitudinally increasing chlorophyll concentrations with maximal values of 174 µg L^?1 in 2009 and 123 µg L^?1 in 2011. Additional samples of the benthic bivalves along the river stretches revealed high densities of the filter feeders in the Rhine that could potentially explain losses of plankton production. Their densities in the Elbe were significantly lower, making important losses to benthic filter feeders unlikely. However, strong phytoplankton growth was observed during the sampling campaign in 2011 in the Rhine coinciding with a low discharge event. This resulted in an exceptionally high chlorophyll value of up to 244 µg L^?1 in the lower river sections, a value that was not reached in the last two decades of continuous water quality monitoring in the Rhine. Even though we cannot fully explain this phenomenon, it shows that phytoplankton has a high growth potential in the Rhine but is usually controlled by other mechanisms. Tributaries represented an additional and important source of plankton biomass and suspended substances in the Rhine, whereas they primarily diluted the plankton concentrations in the Elbe. Copyright © 2015 John Wiley & Sons, Ltd.     

黄河生态水文评估指标体系的构建及案例研究

【目的】维持良好的生态水文联系是维持河流健康生命的基础,开展河流生态水文评估指标体系研究对进一步认识、量化和恢复河流系统健康状况具有重要指导意义。【方法】在总结、分析国内外相关研究成果的基础上,结合黄河生态水文特点,建立指标体系构建原则,通过因素分析提取可以表征黄河河流生态水文情势的50个指标,构建黄河生态水文评估指标体系,并将指标体系应用于黄河干流兰州断面的生态水文评估。【结果】实例研究结果表明,兰州断面的整体水文改变度为0.722,属高度改变。其中1、2、8、9月平均流量、逆转次数、高流量延时、枯季最大流量、丰季最大流量发生时间、大小洪水次数、涨水次数与延时等指标改变强烈,会对黄河兰州段的水沙关系、生物种群数量、幼苗比例、栖息地环境以及滩区、湿地、洪泛区的植被与动物种类产生较大的影响。与IHA指标体系对比,两者的评估结果基本一致。【结论】黄河生态水文评估指标体系在实际应用中可行,相对IHA指标体系更细致、更全面、更准确,可较好的反映黄河生态水文态势。     

变质岩地下水的富集条件与寻找方法

为找出变质岩区的地下水，通过分析变质岩区的岩性及构造、富水类型及富水条件，结合电法测量，提出了寻找不同富水类型地下水的方法。     

突发性洪水对港口及其集疏运通道的影响

在全球气候变化的背景下,极端降水导致的港口及港口城市突发性洪水问题受到越来越多的关注。为了获得精确的高分辨率洪水淹没图,以英国港口城市利物浦为例,基于有限体积法的Godunov格式和HLLC近似黎曼解,利用计算机图形处理器并行计算求解二维浅水方程,模拟了极端降水情景下突发性洪水在港口城市复杂地形上形成的表面径流,研究港口区域及其集疏运道路的淹没情况。研究结果表明,突发性洪水对利物浦港口码头区域影响甚小,但对港口堆场、后方服务区、临港工业区以及集疏运道路有不同程度的影响。研究成果可以为港口及其集疏运规划提供理论支撑。     

用模糊物元模型综合评价陕西省水资源可持续利用程度

在模糊物元分析的基础上，结合欧氏贴近度概念，建立了基于欧氏贴近度的区域水资源可持续利用评价模糊物元分析模型，并将之用于陕西省水资源可持续利用程度的评价。实例研究表明，相对于常规的矢量模法、模糊综合评价法、人工网络法，模糊物元分析方法所得结果更能反映问题的实质，取得的效果更好，评价结论更为科学合理，有助于解决陕西省的水资源问题。     

HRM implementation by line managers: explaining the discrepancy in HR-line perceptions of HR devolution

Previous studies already established the idea of a partnership in which HR professionals and line managers share an organisation’s HRM responsibility. Yet, this relationship is often plagued by conflicts and other obstacles. As such, a perceptual discrepancy is likely to exist between both parties on the degree of HR devolution, which may eventually lead to bad performance. Using survey data, we empirically analyse which factors may explain a perceptual discrepancy between HR professionals and line managers on the latter group’s role in HRM. Results show that the HR-line discrepancy on the degree of HR devolution is rooted in differences in perception on several other factors, including organisational support, (personnel) red tape, the line’s individual capacity and age. Overall, though, it is a matter of understanding both HR’s expectations and the line’s experiences in all aspects of their partnership.     

我国商业银行效率测度分析——基于SFA技术的实证研究

基于2005~2012年22家商业银行的非平衡面板数据,运用超越对数生产函数形式的SFA技术实证分析了所选银行的经济效率值,选取的银行包括国有大型商业银行、地区性商业银行、农村和外资商业银行等类型。为考察所有制对银行效率的影响,以税前利润收入和贷款净额分别作为产出指标建立模型。并对低效率残差项的不同分布假设的精度进行比较,选出最优模型。研究表明:近年来我国商业银行效率整体水平有较大幅度提高;所选银行中,外资银行效率水平最高,地区性商业银行效率值最分散,国有商业银行的效率较集中,普遍位于0.8左右,农村商业银行的效率最低。最后,针对不同所有制银行的特点,提出提高其效率的政策建议。     

Identifying beliefs underlying successors’ intention to take over the farm

The youth out-migration of rural areas, the ageing of farmer population and the lack of a successor within the farm family imply some drawbacks for rural development and for a more sustainable agriculture. This study used the reasoned action approach (RAA) to identify the beliefs underlying Brazilian successors’ intention to take over the farm. The RAA hypothesizes that successors’ intention to take over the farm is determined by three constructs: attitude, perceived norms and perceived behavioral control. These three constructs are derived from behavioral, normative and control beliefs. Results showed that the behavioral beliefs ‘Satisfaction for taking care of family farm assets’ and ‘Ease for managing the farm’ influence successors’ evaluation (attitude) of taking over the farm. The normative beliefs ‘Father’ and ‘Mother’ influence successors’ perceptions about the social pressure (perceived norms) to take over the farm. The control beliefs ‘Ease to buy more land’ and ‘Professional recognition’ influence successors’ perceptions about their own capability (perceived behavioral control) to take over the farm. The identification of these beliefs revealed important implications for designing interventions to encourage successors to take over the farm.