封育措施对呼伦贝尔草甸草原区草地生产力的影响

目的 研究围封条件下植物群落中物种变化的分布特征,有助于解释退化草地在不同围封阶段演替规律。方法 文章以温性草甸草原为研究对象,采用野外定位随机采样方法,调查群落生物量、植物物种种类、密度、盖度及高度,探讨时间尺度封育状态下的温性草甸草原植物群落特征、物种多样性的变化。结果 （1）封育措施显著增加了群落盖度,比围栏外的自由放牧样地提高了13.79%~114.75%,且随着封育年限的增加群落盖度表现出先增加后降低;而封育措施对群落密度没有显著性影响。（2）封育显著增加了植被地上生物量、地下生物量以及禾草生物量,其中地上生物量较围栏外的自由放牧样地提高了66%~887.3%,禾草生物量和地上生物量均随着封育年限的增加表现出先增加—降低—增加—降低的波动变化,地下生物量在监测年份下表现为先增加后降低的变化;封育措施可以提升植物多样性,随着封育年限的增加,多样性指数和丰富度指数呈现先增加后降低的变化趋势。结论 封育措施可以显著提高草地生产力,并且对物种多样性也有一定的促进作用,是应对退化温性草甸草原恢复的有效措施,但退化草地在长期围封后,应进行适度利用来维持较高的生产力。     

公司违规与审计收费：违规公告异质性和作用机制

以审计定价模型为切入视角,探讨了违规公告内容与审计收费的关系,并进一步剖析违规诱增审计收费的作用机制。研究发现：违规公告异质性内容会对审计收费产生差异化影响,违规类型严重性和多样性、处罚措施严厉性均会显著诱增审计收费,而处罚措施多样性不会显著提高审计收费。进一步地,公司违规通过“审计成本”和“风险溢价”两条平行中介路径来诱增审计收费,且“审计成本”这条路径会受到事务所规模、任期长短、是否更换等变量的显著调节。研究说明违规公告文本内容能协助审计师评估风险,也表明不同情境下违规对审计收费的作用机理存在差异性。     

喀纳斯景区草地景观美学价值评价及影响因素分析

[目的]自然景区的美学价值大小直接决定着其旅游开发的成败,为了解喀纳斯景区草地景观美学价值。[方法]该文选用心理物理学派的美景度评价体系,对景区内4个区域草地景观的美景度进行了定量评价,并依据上述样地植物群落α多样性和功能群结构的分析,探讨了植物多样性对喀纳斯景区草地景观美景度的影响。[结果]研究表明:喀纳斯景区草地景观美学价值整体较高,α多样性指数居中的草地美景度得分较高,α多样性指数较高的草地美景度次之,α多样性指数较低的草地美景度最差;随着功能群中一、二年生植物重要值的上升,多年生杂类草的重要值下降,美景度呈降低的趋势;美景度与平均高度、平均盖度、生物量、Shannon-Wiener指数、Margalef丰富度指数、Simpson指数和多年生杂类草重要值呈显著正相关,而与一、二年生杂草重要值呈显著负相关。[结论]因此,草地植物多样性是草地景观美学价值的重要载体,旅游活动导致草地群落植物多样性发生改变,进而深刻影响了草地景观的美学价值。     

Context matters: Oil palm production and women's dietary diversity in the tropical forest of Cameroon

Oil palm is one of the most rapidly expanding food and cash crops in many tropical regions with significant environmental implications, but also economic gains. Previous analyses have established that this expansion is associated with changing gender roles and time allocation for women. Time allocation is an important determinant of maternal and child nutrition as well as well-being. We use a rich farm household survey from a native oil palm production hotspot, Cameroon, to examine the associations between oil palm production and women's dietary diversity. Using different estimation and identification strategies with some sensitivity checks, we show that oil palm is associated with lower dietary diversity for women, measured as the minimum dietary diversity for women and the minimum adequacy diversity diet. We explore heterogeneity in the various food groups consumed by women and show that oil palm production is associated with lower consumption of mainly pulses, fruits and vegetables. These findings contrast with the literature that has established some positive dietary diversity implications of oil palm expansion in Southeast Asia. We carefully discuss these findings and argue that context matters and may explain these differences. Particularly, we show that oil palm production is negatively associated with farm production diversity in Cameroon. Notwithstanding, we also confirm previous findings that highlight that oil palm production is associated with higher income. These insights add to the debate on the implications of oil palm expansion in tropical environments. Moreover, they can guide policy in designing more tailored interventions that address nutrition issues and improve rural development.     

Managing Cultural Diversity in Collaborations: A focus on management tensions

Abstract

This article explores the management of cultural diversity in public and not-for-profit collaborations spanning organizational, professional and national boundaries. Through the framing of a culture paradox, it identifies three interrelated tensions pertaining to the management of cultural diversity towards collaborative advantage. These tensions address: interactions between organizations within a collaboration; interactions between individual actors and their orientation towards the collaboration and their host organization; and the quantity and extent of cultural diversity within a collaboration. The culture paradox and its inherent management tensions provide theoretical and practical conceptualizations that are relevant to management and governance of collaboration.     

The Ethical Case for Affirmative Action

Affirmative action has been a particularly contentious policy issue that has polarised contributions to the debate. Over recent times in most western countries, support for affirmative action has, however, been largely snuffed out or beaten into retreat and replaced by the concept of ‹diversity management’. Thus, any contemporary study that examines the development of affirmative action would suggest that its opponents have won the battle. Nonetheless, this article argues that because the battle has been won on dubious ethical grounds it is important that we do not allow affirmative action to sink unnoticed. This article explores and challenges the ethical and philosophical underpinnings of opponents’ views and finds their cases against affirmative action are not ethically sound. The article concludes there are strong ethical grounds for those organisations which seek to do well, to reassert affirmative action programmes in the global efforts to eradicate systemic discrimination and disadvantage.     

Contextual Factors Affecting Quality of Work Life and Career Attitudes of Gay Men

With the current political environment (such as new legislation recognising gay and lesbian couples) and societal changes (such as increasing disclosure of sexual identity in the workplace) in countries such as the USA and Australia, organizations are increasingly recognising the existence of their gay and lesbian employees. This paper reports on an on-line survey of 581 working gay men, examining their quality of work life and career attitudes. The findings of the research provide a strong indication that contextual factors affect the quality of work life and work attitudes of gay men.     

The Emergence of Corporate Governance from Wall St. to Main St.: Outside Directors, Board Diversity, Earnings Management, and Managerial Incentives to Bear Risk

Recent corporate events have brought a heightened public awareness to corporate governance issues. Much work has been accomplished to date, but it is clear that much more remains to be done. This paper provides a review of empirical research in four relevant areas of corporate governance. Specifically, the paper provides an overview of (a) the role that outside directors play in monitoring managers, (b) the emerging literature on the impact of board diversity, (c) the existence of and incentives for corporate executives to manage firm earnings, and (d) managerial incentives to bear risk.     

在线品牌与离线品牌之比较

互联网已经基本上改变了市场营销环境 ,在线品牌与离线品牌的重要性毋庸置疑 ,虽然在线品牌与离线品牌建立的方式是一样的 ,但是在线品牌与离线品牌无论是在两种品牌的环境、品牌增加价值的来源 ,还是在品牌价值的传递过程、成功的管理要素上 ,都存在着差异性     

最优天线选择的空时分组编码

本文针对TD－SCDMA系统的MIMO（Multiple-Input Multiple-Output)信道，采用天线选择技术来提高空时分组码（Space-Time Block Coding)的分集性能。其依据是利用TDD系统上、下行信道的互易性，将系统对上行信道的估计直接应用于行链路。仿真结果表明，将天线选择技术与空时分组码（STBC）相结合对系统的误码率性能有较大的改善。