Indigenous responses to drought in sub-Saharan Africa*

Drought is a frequent occurrence in contemporary sub-Saharan Africa, and the existence of periodic drought can be documented over hundreds of years. As a consequence of the routine rainfall shortages that affect them, agricultural and pastoral societies have developed a number of social institutions and mechanisms for bridging temporary food production shortfalls caused by drought. Drawing on the literature and field data from southeastern Kenya, this paper discusses a number of regular indigenous responses to short-term drought in sub-Saharan Africa. Changes in these patterns in the present day are also discussed. It is concluded that market-based responses are now the most important strategies, but that traditional institutions remain significant and contribute to the viability of drought-affected societies.     

On the value of endangered and other species

This paper describes two frameworks—utilitarian and Kantian—society uses to make decisions concerning environmental management and, in particular, species protection. The utilitarian framework emphasizes the consequences of choices for prior preferences. A perfectly competitive market, on this model, correctly values environmental resources. The Kantian approach identifies rules appropriate to recognized situations given the identity of the decision maker. It relies on democratic political processes and institutions to provide the means by which citizens determine the identity of their community—its moral character and aspirations—and match appropriate rules to recognized situations. This paper argues that markets do not fail in any general way in measuring the economic value of plants and animals. Market prices, in general, correctly represent the marginal or exchange value of species. If society legislates against extinction, this must be understood as an exercise in Kantian decision making in view of the moral value of species, not as an attempt to correct a market failure or to promote social welfare or utility.     

山地灾害对新重庆社会经济环境的重要影响

基于新重庆的山地环境与社会经济环境特征，结合该区山地灾害大量的综合调研资料，对境内主要山地灾害类型及其现状进行归纳；对其严重的社会经济影响进行了较为深入的分析；在此基础上得出了几点有益的认识。     

HSE项目管理体系中环境保护专业的作用

在对比国内建设项目环保管理体系和HSE环保管理体系的基础上，总结了PMC项目环保管理工作的经验，对HSE项目管理运作模式中环保专业的职能和作用进行了一定程度的探讨。     

城市污水净化的环境效益与环境影响分析

对佛山城市污水净化系统的环境响应和效益预测原则，城市污水净系统正式运转将对佛山水道化纤厂至人民桥段及佛山涌水质有明显改善，其社会效益十分显著，但净化系统的建设交将带来以恶臭、卫生防疫和噪声等方面为主的不利环境影响。因此在城市环境建设中应尽量减少城市污水净化的负面影响，充分发挥其环境效应和社会效益，为城市环境综合整治创造良好的条件。     

环境保护与金湖旅游并举

阐述了环境保护带动金湖旅游经济可持续发展的现实意义。     

Why bio-physical and social scientists can speak the same language when addressing Sustainable Development

Scientists assert that integrated research is a foundation of Sustainable Development. However, they often presume that differences between the bio-physical and social sciences are hurdles in the way of integration. We show that need not be the case. The problem lies in the way environmental research is organised. The essay goes on to discuss how the problem is being resolved, and the implications for ‘environmental science’.     

Relative importance of multiple plumage ornaments as status signals in golden whistlers (<Emphasis Type="Italic">Pachycephala pectoralis</Emphasis>)

Status signals are traits that advertise an individual’s competitive abilities to conspecifics during aggressive disputes. Most studies of status signals in birds have focussed on melanin-based plumage signals, but recent research shows that carotenoid-based signals may also play a role in aggressive signaling. We assessed the relative importance of melanin- and carotenoid-based plumage patches as agonistic signals in a small passerine, the golden whistler (Pachycephala pectoralis). Display signals in male golden whistlers include an unpigmented white throat patch, a carotenoid-based yellow breast and nape band, and a melanin-based black chin-stripe. We found that only the white throat patch was correlated with contest-related attributes. Males possessing large throat patches defended larger territories and commenced breeding earlier. When caged males with either experimentally reduced, or unmanipulated throat patches were presented to conspecifics, those with experimentally reduced patches attracted less aggression from male subjects. Focal males also responded faster to caged males with throat patches similar in size to their own, suggesting that they may assess relative throat patch size before engaging in aggressive encounters. Females did not discriminate between “reduced” or “control” treatments. Our data strongly suggest that only the unpigmented throat patch functions as a status signal. As this signal is unlikely to have significant development costs, honesty may be maintained through social costs.     

Division of labor between undertaker specialists and other middle-aged workers in honey bee colonies

A primary determinant of colony organization in temporally polyethic insect societies is inter-individual variation in behavior that is independent of worker age. We examined behavioral repertoires, behavioral correlates of adult development, and spatial distributions within the hive to explore the mechanisms that produce behavioral variation among middle-age honey bees (Apis mellifera). Individually labeled undertakers, guards, food storers, and wax workers exhibited a broad range of task-related behavior, but bees tagged as undertakers were more likely to subsequently remove a corpse from the hive and handle a corpse compared to other middle-aged bees. The activity level of undertakers was similar to other task groups, suggesting that undertaking specialists were neither hyper-active “elites” nor quiescent “reserves” that become active only when a dead bee stimulus is present. Undertakers also were more likely to remove debris and to remain in the lower region of the hive or near the entrance, even when not engaged in corpse removal; both preferences may promote colony efficiency by reducing inter-task travel times. Guards and undertakers were less likely to perform behavior normally associated with young bees compared to food storers and wax workers. Undertakers and guards also initiated foraging at earlier ages than the other task groups. These results suggest that undertakers and guards may be slightly developmentally advanced compared to food storers and wax workers. There also was evidence for lifetime differences in behavioral preferences which could not be explained by differences in adult development. Bees tagged as undertakers were more likely to subsequently remove a dead bee during their entire pre-foraging career compared to other task groups or members of their general age cohort. Differences in both the rate of adult development and individual behavioral preferences, both of which may be subject to genetic and environmental influences, are important determinants of inter-individual variation among honey bees of middle age. Received: 5 February 1997 / Accepted after revision: 27 May 1997