On the extraction of an exhaustible resource by a monopoly

Hotelling's r-percent rule does not hold for monopoly extractors of durable exhaustible resources. An example with a nondurable resource in which the rule also fails to hold is presented. An economy with a fixed average propensity to save is modelled. The monopoly extractor recognizes that resource extraction, by affecting output and hence capital accumulation, affects future demand. The firm exploits this effect by causing the marginal profitability of extraction to grow faster or slower than the rate of interest, depending upon initial conditions. Conditions are developed under which the growth rate will be less than the interest rate.     

The behavioral component in the meaning of places

How do people think about the physical setting in the world around them? Part of the answer to this question may be in terms of the behaviors that occur there. To explore people's knowledge of behavior—place associations, twenty places (shown via color photographs) were assessed in five ways: (a) ratings of the place's suitability for each of eleven behaviors, (b) ratings of the expected frequency of occurrence of the eleven behaviors, (c) free listings of reasons for going to each place, (d) free listings of activities-while-there and (e) free listings of activities associated with the place. Results showed that people can distinguish places on the basis of behaviors, that the behavioral component of place meaning is composed of distinct aspects, and that knowledge of behavior is related to a global, overall representation of a place.     

Acute toxicity of two insecticides to tubificid worms, Tubifex tubifex and Limnodrilus hoffmeisteri

Acute toxicity and presumable harmless concentration of two commercial insecticides, Furadan 3G and Malataf 50E were reported for tubificid worms, Tubifex tubifex and Limnodrilus hoffmeisteri. L. hoffmeisteri were found more susceptible to both the insecticides; the Furadan was found to be more toxic than Malataf to tubificid worms. Analysis of variants showed a significant difference between safe concentrations of the same insecticide to different species.     

Adsorption of crude oil on arctic terrain

Arctic terrain was divided into three layers, moss, detritus and clay, and each layer was contacted with Norman Wells crude oil. Chromatographic analysis of the crude oil extracts of the terrain layers showed that the adsorption capacity of the terrain increased with increasing organic content. The higher molecular weight n-alkanes were adsorbed to a greater extent than lower n-alkanes on the moss and detritus layers. Of the aromatics, p-xylene was adsorbed to a greater extent than benzene on all three layers of the terrain. Retention of crude oil components on Arctic terrain in the event of an oil spill would be in accord with these findings.     

A STUDY OF THE SURFACE SYNOPTIC CIRCULATION PATTERNS IN ASSOCIATION WITH THE DROUGHT OF THE 1960's IN THE NORTHEASTERN UNITED STATES1

A comparative evaluation is made of the frequency of air mass and frontal types during a 4-year representative portion of the drought as opposed to an equivalent non-drought period. Selection of the non-drought period is based on the Palmer Drought Index. Results indicate a statistically significant increase in the occurrence of continental polar air during the drought. Other conclusions concerning conditions during the drought, not statistically significant but worth further study, are: lower frequency of maritime tropical air in the summer months, more occurrences of cold and occluded fronts, and fewer occurrences of stationary fronts.     

论北京城市建设的综合减灾问题

本文针对北京城市建设面临的自然与人为灾害背景,简要论述了北京地震、水灾、火灾及“新致灾源”的历史及现状,强调开展首都圈灾害研究及减灾规划设计的重要性,并提出了系统的减灾方略及相应的管理构想。     

控制人口 保护资源 为子孙留下蓝天碧水绿地

建国40多年来,淄博市的国民经济和社会事业迅速发展,已经成为一个以重工业为主体的重要工业城市。同时,随着经济规模的迅速扩大,人口、资源与环境三大问题越来越突出。面对这样的市情,淄博市采取各种措施,突出重点,集中力量主攻薄弱环节,严格控制人口增长,保护资源,综合整治污染,取得了很大成效,初步走上了经济和社会事业与人口、资源、环境协调发展的轨道。     

Promotion of hexadecyltrimethyleamine bromide to the damage of Alexandrium sp. LC3 by cupric glutamate

The effect of hexadecyltrimethyleamine bromide （HDTMAB） on the removal of A lexandrium sp. LC3 under cupric glutamate stress was investigated. Toxic effect of cupric glutamate on A lexandrium sp. LC3 was significantly promoted in the presence of HDTMAB, especially at 3.0 cmc of HDTMAB. It was found that the sulfhydryl group content of the cell decreased, while the malonaldehyde content and membrane permeability increased when A lexandrium sp. LC3 was treated with HDTMAB and cupric glutamate complex, compared with cupric glutamate alone. The data suggest that HDTMAB might stimulate the damage of A lexandrium sp. LC3 by enhancing the membrane permeability.     

Metal bioaccumulation and metallothionein concentrations in larvae of Crassostrea gigas

Larval stages of bivalve molluscs are highly sensitive to pollutants. Oysters from a hatchery from Normandy (English Channel) were induced to spawn, and fertilized eggs were exposed to copper or cadmium for 24 h. Metal accumulation (from 0.125 to 5 microg Cu L(-1) and from 25 to 200 microg Cd L(-1)) and MT concentrations were measured in larvae. Compared to controls, larvae accumulated copper and cadmium with an increase in MT concentrations particularly with cadmium (i.e. 130.96 ng Cu (mg protein)(-1) and 12.69 microg MT (mg protein)(-1) at 1 microg Cu L(-1) versus 23.19 ng Cu (mg protein)(-1) and 8.92 microg MT (mg protein)(-1) in control larvae; 334.3 ng Cd (mg protein)(-1) and 11.70 microg MT (mg protein)(-1) at 200 microg Cd L(-1) versus 0.87 ng Cd (mg protein)(-1) and 4.60 microg MT (mg protein)(-1) in control larvae). Larvae were also obtained from oysters of a clean area (Arcachon Bay) and a polluted zone (Bidassoa estuary) and exposed to copper in the laboratory, their MT concentration was measured as well as biomarkers of oxidative stress. Biomarker responses and sensitivity to copper for the larvae from Arcachon oysters were higher than for those from Bidassoa.     

自然权利的批判与辩护

环境伦理的突出功能表现在对人与自然关系的调整上。从法学视角切入．以“权利”作为分析文本．论述了人类中心主义与非人类中心主义在“自然权利”上的理论分歧．人类中心主义者从权利的一人性、权利义务的不对等性、主张自然权利的非现实性以及自然权利的不可操作性四个方面对自然的权利提出了批判．而非人类中心主义者指出权利撅念的在不断地扩展．人类中心主义不可能完全解决好人与自然的关系,自然权利存在着转化为在法律上具有可操作性的可能．并且自然权利理论已在法律实践领域拓展．对自然的权利进行了辩护。由此提出了“非人类中心主义”、“自然的权利”的环境伦理定位。