政府主导、人口流动与城乡收入差距

中国经济增长具有典型的政府主导特征,通过构造一个包含城镇和农村经济产出的社会福利函数来分析政府主导型经济增长对城乡收入差距的影响关系,并基于中国城镇化发展实际分析了人口流动对城乡收入差距的影响,在此基础上提出研究假说,统计中国1997—2014年省际面板数据,采用泰尔指数测度城乡收入差距并分别进行静态和动态回归分析与检验。静态研究发现政府主导和人口流动显著地拉大了城乡收入差距,但是二者的交互项对城乡收入差距的确具有收敛效应,即随着人口流动的增加,政府主导对城乡收入差距的边际贡献会降低,同样随着政府主导的提升也会降低人口流动对城乡收入差距的边际贡献,这种影响关系在分区域的回归中依然成立,并通过了稳健性检验;动态研究发现全国和分区域中城乡收入差距的变动存在显著的正向路径依赖特征,全国层面政府主导显著地拉大了城乡收入差距,而人口流动及其与政府主导的交互项则显著地缩小了城乡收入差距,但分区域来看政府主导和人口流动对城乡收入差距的影响存在显著的区域异质性,并通过了稳健性检验。因此缩小城乡收入差距不应设置单一的政策目标,需要建立多方面的政策配套体系,逐步矫正政府主导型经济中造成的政府职能异化,精准识别地方财政收支量的规模和结构条件,扩大涉农业务投资的规模,激活农村经济发展活力;在城乡户籍制度改革中进一步打破城乡分割藩篱,大力发展非农产业,增加农民的非农就业机会,促进农民的非农化就业和城镇化迁移,提升城镇化发展质量;最终通过一系列的配套性制度安排,旨在加强支持农业发展和农村建设,促进农民收入增长的制度供给,实现城乡共享发展。     

Household incidence of pollution control policies: A robust welfare analysis using general equilibrium effects

This study assesses the incidence of pollution control policies on households. In contrast to previous studies, we employ an integrated framework combining a multisector general equilibrium model with a stochastic dominance analysis using household-level data. We consider three policy instruments in a domestic emission trading system: (i) an output-based allocation (OBA) of permits; (ii) the use of the proceeds of permit sales to reduce payroll taxes (RPT); (iii) and the use of these proceeds to reduce consumption taxes instead (UCS). The general equilibrium results suggest that the return to capital is more negatively affected than the wage rate in all simulations, since polluting industries are capital intensive. Abstracting from pollution externalities, the dominance analysis suggests that all three policies have a normatively robust negative (positive) impact on welfare (poverty). Formal dominance tests indicate that RPT first-order welfare dominates OBA over all values of household incomes. UCS also first-order poverty dominates RPT for any choice of poverty line below $CAN 18,600, and poverty dominates for any poverty line (and thus welfare dominates) at the second order. Finally, while the three pollution control policies do not have a numerically large impact on inequality (in comparison to the base run), statistical tests indicate that inequality increases significantly more with OBA and RPT than with UCS.     

Queen and worker policing in the monogynous and monandrous ant, Diacamma sp.

Policing behavior that prevents workers from laying male eggs was examined in the monogynous and monandrous ponerine ant Diacamma sp. from Japan, in which a singly mated worker called a “gamergate” reproduces as the functional queen in each colony. Since oviposition by virgin workers is rare in the presence of a gamergate, we separated a portion of workers from the gamergates and induced their oviposition experimentally. When orphaned workers had started to oviposit, they were returned to the original colonies, where they continued to lay eggs for a while. The gamergates and other workers interfered with the laying workers by aggressively taking and finally eating the eggs. In total, 60% and 29% of the worker-derived eggs were eaten by gamergates and non-mother workers, respectively. The observed worker-worker interactions were not driven simply by competition to leave own sons, because non-laying non-orphaned workers interfered with worker reproduction. Furthermore, orphaned workers were usually attacked by non-orphaned workers soon after colony reunification. These results indicate that both queen policing by gamergates and worker policing in this species are mechanisms inhibiting worker oviposition. The gamergate contribution to policing was proportionately larger than that of workers, but among virgin workers, the relationship between dominance rank and contribution to policing was not clear. But about 11% of the eggs were not policed and were added to egg piles, especially in large colonies. Worker policing in a monandrous and monogynous eusocial Hymenoptera contrasts to other recent findings, and possible genetic, social, and ecological factors for its evolution in Diacamma sp. are discussed. Received: 16 November 1998 / Received in revised form: 9 February 1999 / Accepted: 21 February 1999     

浅谈生态环境影响评价中的景观生态学法

景观生态学是近十几年发展起来的一门新兴学科,且现代景观生态学己经成为生态学领域中令人瞩目的一个分支,其发展为生态环境评价提供了有力的工具,近几年国家环境保护部<非污染生态影响评价技术导则>引入景观生态学的概念框架和理论方法,主要运用景观生态学中的优势度原理,通过对优势度的计算,分析项目建设前后优势度的变化情况,评价由于项目建设引起的生态环境影响.本文通过对景观生态学历史、现状以及未来发展趋势的研究,体现景观生态学法在现今生态环境影响评价中的重要作用.     

Age- and state-dependent reproductive effort in male mountain goats, Oreamnos americanus

In mammalian polygynous mating systems, male reproductive effort consists mainly of male–male competition and courting of females, which entail substantial somatic costs. Males are thus expected to adjust their reproductive effort according to their age and condition. In this study, we examined how activity budgets of male mountain goats (Oreamnos americanus), a polygynous ungulate, varied with age in a marked population over two periods: (1) summers 1995–2006 and (2) ruts 2004–2006. We then assessed if the proportions of time spent in male–male competition and courtship behaviors were influenced by age-specific body mass and social rank during the rut. Males spent most of their time foraging and resting during summer, and rested more and foraged less with increasing age. During the rut, pronounced shifts in activity budgets occurred as juveniles (1–2 years) increased time spent foraging, whereas adults (≥3 years) increased standing and time spent in social interactions at the expense of foraging. At old age, reproductive effort either stabilized or decreased slightly, providing weak support for the ‘mating strategy–effort’ hypothesis, predicting that courtship behaviors should peak in prime-aged males. Age-specific body mass did not affect time spent in male–male competition, but was positively related with time spent in courtship behaviors, providing support for the ‘individual quality’ hypothesis, predicting that males with more resources at the start of the rut should spend more time in mating-related activities. Age-specific social rank did not affect reproductive effort. Surviving to prime age while increasing mass each year should thus allow male ungulates to gain greater ability to court estrus females.     

景观生态学在建设项目生态环境影响评价中的应用

景观生态学目前是国家环境保护总局《非污染生态影响评价技术导则》引入的概念框架和理论方法。本文通过景观生态学在不同性质建设项目中的运用分析,进行了一定的尝试,更加希望在今后建设项目生态环境影响评价工作中得到修正和完善。     

景观生态学在公路建设项目环境影响评价中的应用

景观生态学中的优势度原理在评价开发建设项目对生态系统完整性及其结构与功能稳定性方面具有很好的适用性，但在线型开发建设项目环境影响评价中很少应用。以公路建设为例，探讨了在线型开发建设项目生态环境影响评价中的应用。     

Effect of Grazing and Climatic Changes on Alpine Vegetation of Tungnath,Garhwal Himalaya,India

Effect of grazing and changing climate on vegetation composition of alpine pasture at Tungnath, Garhwal Himalaya was observed. Growth form pattern and phytosociological attributes were analyzed during 1988 under grazed (exposed to extensive grazing) and ungrazed (protected from grazing) conditions. These observations were repeated during 1998. It was observed that number of early growing species and long vegetative growth cycle species had increased at both sites in 1998 in comparison to 1988. Further, some species, viz., Poa alpina, Polygonum spp., Ranunculus hirtellus, Anemone spp., are predominantly found near the timberline-subalpine region. These species are less palatable and were present at both sites with higher dominance (TBC) and niche width in 1998 indicating wide distribution of the species along an altitudinal gradient. These observations indicated the migration of these species towards upper slopes of alpine. Species diversity was also higher after ten years. However, it is clear that climatic changes alone are not responsible for these vegetational shifts. In fact, human-induced changes are the main reason for habitat destruction and changes in vegetation composition of the alpine region of Garhwal Himalaya. Before final conclusions can be made, long-term studies on vegetation composition and changes are needed, especially in Himalayan region.     

Exploitative compensation by subordinate age-sex classes of migrant rufous hummingbirds

Summary The three age-sex classes of rufous hummingbirds (Selasphorus rufus) that directly interact on southward migratory stopovers in our California study system differ in territorial ability and resource use. Immature males are behaviorally dominant to adult and immature females and defend the richest territories. Here, we test the hypothesis that the territorially subordinate age-sex classes compensate exploitatively for their exclusion from rich resources. Our results show that females were able to accumulate energy stores at rates comparable to males despite their subordinate territorial status. Territorial females gained body mass at the same rate and in the same pattern as males, and resumed migration at the same body masses. Moreover, during periods when birds were nonterritorial and used dispersed resources, adult and immature females maintained or gained body mass, whereas immature males lost mass. We suggest that females may be energetically compensated by (1) lower costs of flight incurred during foraging and defense, resulting from their lower wing disc loading, and (2) greater success at robbing nectar from rich male territories, resulting from duller coloration (immature females), experience (adult females), and, possibly, hormonal differences. In the future, experiments will be necessary to distinguish the various hypotheses about the mechanisms involved in compensation. Correspondence to: F.L. Carpenter     

What makes affirmative action‐based hiring decisions seem (un)fair? A test of an ideological explanation for fairness judgments

Studies show that Whites tend to show the lowest level of support for affirmative action (AA) policies. Opponents of AA often argue that this is because it violates principles of meritocracy. However, self‐interest (based on social identification with those adversely affected) could also explain their opposition. In three studies, we varied whether an Asian or White male is adversely affected by AA to test another explanation; namely, that Whites' fairness judgments are based on both the adversely affected person's race and the fairness evaluator's ideological beliefs. Although we found some support for the meritocratic explanation, this was not sufficient to explain why Whites view AA as (un)fair. Instead, we found strong support for our prediction that Whites who are opposed to equality perceive more unfairness when a White (vs. Asian) was harmed by AA, whereas Whites who endorse egalitarian ideologies perceive the opposite. This finding suggests that neither self‐interest nor meritocratic explanations can fully account for Whites' opposition to AA. Copyright © 2014 John Wiley & Sons, Ltd.