环境问题与"可持续发展"道路存在的误区

环境问题本质是人的问题,具体表现于人口问题和人的德行问题。文章认为导致我们系列环境政策没有起到预想结果的原因在于我们"德行"中存在的认识误区,分析了这些认识误区;提出解决环境问题的根本途径是改造我们的"德行"并知道我们生活在地球"极限之内"。     

支持人居环境健康发展的自然调和理论研究

人类聚居的城市环境和建筑环境，与人类自然气象环境之间持续着动态的自然调和作用，当然调和理论是支持人居环境可持续发展的基础理论之一；文中圈定了自然调和理论研究的框架体系；介绍了面向人居环境的可持续发展所进行的自然调和技术研究进展；剖析了自然调和理论问题研究的科学性。     

红壤丘陵脆弱生态环境的形成与整治对策

通过对我国东南部红壤丘陵区生态状况的历史回顾，分析了该区脆弱生态环境形成的主要原因，提出其整治应采取的生态、经济、社会诸方面的综合措施。     

Is Current Consumption Excessive? A General Framework and Some Indications for the United States

Abstract:  Many prior studies have explored the implications of human population growth and environmentally problematic technologies for biodiversity loss and other forms of environmental degradation. Relatively few, however, have examined the impacts of the level and composition of consumption. We offer a framework that shows how the level and composition of a society's total consumption relate to the uses of various forms of capital and to the sustainability of natural resources and human well-being. We relate the framework to two main approaches—top–down macro studies and bottom–up computer models—for measuring whether overall consumption in the United States satisfies a sustainability requirement. Existing top–down studies have shortcomings that bias their results toward optimism, and current computer simulation models, although strong on revealing biophysical outcomes, are limited in their ability to evaluate impacts on human well-being. Although some ambiguities arise in determining whether overall consumption in the United States is excessive, our conclusions regarding the composition of U.S. consumption are unambiguous. Distorted consumption patterns and associated production methods lead to excessively rapid natural resource depletion; greater conservation would yield gains to current and future generations that more than compensate for the sacrifices involved. Public policies that deal with the composition problem not only would help conserve natural resources and improve current welfare but also would reduce the costs of meeting the goal of sustainability.     

Species Imperilment and Spatial Patterns of Development in the United States

Abstract:  Conservation biologists and others hypothesize that humankind's "ecological footprint" is affected not only by the sheer intensity of human activity but also by its spatial arrangement. We used a multivariate statistical model and state-level data to evaluate correlations between species imperilment and the level and spatial distribution of human settlement and infrastructure development in the United States. The level of human activity—measured by the number of people and households, incidence of roads, and intensity of nighttime lights—was significantly correlated with the ecological imperilment of species. Our regression models consistently showed that a 1% increase in the level of human activity across the United States was associated with about a 0.25% increase in the proportion of plant and animal species considered at risk of extinction by The Nature Conservancy. The distribution of human activity did not affect species imperilment. Our results point to rising levels of human activity—and not some particular (e.g., sprawling) distribution of human activity—as the most relevant anthropogenic factor explaining biodiversity loss in the United States.     

Is boldness affected by group composition in young-of-the-year perch (Perca fluviatilis)?

In young-of-the-year perch (Perca fluviatilis), individuals within groups differed in the degree of boldness, estimated by habitat utilisation and feeding activity in visual contact with a potential predator. We looked at changes in individual behaviour in connection with change of group composition. During the first period, perch were randomly assigned to groups, and time spent in open habitat versus in vegetation and number of prey attacks were registered. The perch were then categorised into personality types (shy, bold, intermediate) according to their behaviour. During the second period, fish were observed when sorted into new groups, each containing only one personality type. Shy individuals showed the largest changes in behaviour, and increased both the time spent in the open and the number of prey attacks when placed into the new groups. Feeding activity in shy fish during the second period was affected by group composition during the first period. After regrouping, bold individuals decreased their time in the open, whereas intermediate individuals did not change behaviour. Time in the open habitat was, to some extent, influenced by the behaviour of the other members of the group, but number of prey attacks was not. The behaviour of fish of the different personality types we have defined in this study seemed to be based on innate traits, but also modified by the influence of other group members and by habituation to the environment.Communicated by J.Krause     

Systemic retention of ingested cantharidin by frogs

Summary Frogs(Rana pipiens) fed on blister beetles (Meloidae) or cantharidin, retain cantharidin systemically. After cessation of feeding, they void the compound relatively quickly. Systemic cantharidin does not protect frogs against ectoparasitic feeding by leeches(Hirudo medicinalis) or predation by snakes(Nerodia sipedon). As suggested by our data, and from reports in the early literature, ingestion of cantharidin-containing frogs can pose a health threat to humans.Paper no. 95 of the seriesDefense Mechanisms of Arthropods; no. 94 is LaMunyon & Eisner, Psyche (in press)     

城市人居环境评价体系的研究及应用

在国内外人居环境理论研究及实践的基础上,提出了由系统层、子系统层和指标层构成的城市人居环境评价指标体系,其中系统层由社会经济环境、自然生态环境、公共设施建设、环境资源保护和环境管理能力五部分组成,子系统层由16个指标组成,指标层由43个具体指标组成。利用统计分析法(Delphi)确定各指标的权值。同时,针对本指标体系结构提出了单项评价和综合评价相结合的评价模式,并设置了城市人居环境质量指数和系统协调度两个综合性指标来全面评价城市人居环境质量。通过对重庆市渝北城区的综合评价,评价结果较客观地反映了该城区的实际。     

Toxic metals status in human blood and breast milk samples in an integrated steel plant environment in Central India

Owing to its unique nutritional and immunological characteristics, human milk is the most important food source for infants. Breast milk can, however, also be a pathway of maternal excretion of toxic elements. Selected toxic elements (As, Pb, Mn,a Hg and Cd) were determined in human breast milk and blood samples obtained from 120 subjects related to an integrated steel plant environment located in central India. Samples of breast milk and blood from subjects living outside the steel plant environment were also analyzed for comparative study. Higher levels of these toxic elements were found in blood samples as compared to breast milk samples. Plant workers showed the higher presence of these metals in their breast milk and blood samples compared to the residents of the area and the subjects living outside the industrial environment, respectively. Mn, Pb and Hg have shown a higher tendency to associate with blood and breast milk than As and Cd. The order of occurrence of these metals in blood and milk samples thus found is Mn > Pb > Hg > As > Cd.     

RAPD扩增中商品酶体系对扩增产物的影响

随机选用了10条RAPD引物，采用3种商品TapDNA聚合酶体系，以5个不同物种的动植物总DNA为模板，进行RAPD扩增，实验发现，在对同一模板、采用同一引物进行的RAPD扩增中，仅仅因为使用了不同的商品TaqDNA聚合酶，获得的扩增产物差别极大；不同商品来源的PCR反应缓冲体系，对扩增产物也有一定影响，但相对较小，这说明，不同的商品酶体系对RAPD扩增产物影响很大，因此，影响RAPD扩增产物稳定性的一个关键因素是商品TaqDNA聚合酶本身；研究中前后一致地使用同一商品TaqDNA聚合酶体系，是成功进行RAPD分析的基础。