阿拉善盟沙尘暴情况调研报告

本文重点介绍阿拉善沙尘暴发生的基本情况并对成因进行了分析，最后提出恢复生态环境防治沙尘暴的频频垄击。     

几种天敌对麦蚜蜜露的行为反应

麦长管蚜和禾谷缢管蚜蜜露的主要糖分为果糖、葡萄糖、蔗糖及两种未知糖分．其中前者以蔗糖含量最高，后者则不含蔗糖．其游离氨基酸种类基本相同，但后者蜜露中未鉴定出苏氨酸；除丙氨酸和组氨酸外，麦长管蚜中各类氨基酸的含量明显高于禾谷缢管蚜，其中单头麦长管蚜日分泌氨基酸量以亮氨酸和丙氨酸最高，分别达到了0．204 7ng和0．137 7ng，而禾谷缢管蚜以丙氨酸和亮氨酸最高，分别达到了0．154 3ng和0．102 5ng．随着蜜露含量的增加，各天敌的搜索与滞留时间显著延长，但逐渐趋于平缓，基本符合逻辑斯蒂增长．燕麦蚜茧蜂在两种蚜虫蜜露上的搜索与滞留时间差异显著，而瓢虫与草蛉类的搜索与滞留时间差异不显著，说明蜜露对捕食性和寄生性天敌的影响不同．图3表1参13     

Employed mothers: Interrole conflict,spouse support and marital functioning

Increased participation by mothers in the labour force may exert a negative effect on working mothers themselves (e.g. interrole conflict) and influence the marital relationship negatively. Recent research suggests that not all individuals experiencing psychological distress suffer psychological strain (e.g. marital discord). Rather, variables such as social support moderate negative effects of psychological stressors. To test this, sixty-four employed mothers (M age = 36 years) completed interrole conflict and spouse support scales. Marital satisfaction, verbal and nonverbal communication were the criteria operationalized to assess marital functioning. Using moderated multiple regression analyses, interrole conflict and spouse support predicted marital satisfaction and verbal communication significantly. In addition, spouse support may moderate negative effects of interrole conflict on marital satisfaction and verbal communication. With regard to nonverbal communication, spouse support was both a significant main effect and possibly a moderator of interrole conflict. The role of spouse support, conceptual and treatment implications, and future research priorities are identified.     

CONSIDERATIONS OF SCALE IN WATER QUALITY MONITORING AND DATA ANALYSIS1

ABSTRACT: An assumption of scale is inherent in any environmental monitoring exercise. The temporal or spatial scale of interest defines the statistical model which would be most appropriate for a given system and thus affects both sampling design and data analysis. Two monitoring objectives which are strongly tied to scale are the estimation of average conditions and the evaluation of trends. For both of these objectives, the time or spatial scale of interest strongly influences whether a given set of observations should be regarded as independent or serially correlated and affects the importance of serial correlation in choosing statistical methods. In particular serial correlation has a much different effect on the estimation of long-term means than it does on the estimation of specific-period means. For estimating trends, a distinction between serial correlation and trend is scale dependent. An explicit consideration of scale in monitoring system design and data analysis is, therefore, most important for producing meaningful statistical information.     

Heroism in a resource crisis: A simulation study

This study examined the effects of individual responsibility and communication in a simulated resource management problem. Subjects faced the problem of how to harvest resources from a regenerating pool so as to maximize their individual harvests without overexploiting the pool. One behavioral option open to individuals involved the sacrifice of a harvesting opportunity in order to add to the pool, thereby benefiting the rest of the group. A 2 x 2 factorial design was used to test the effect of this kind of heroism by (1) including a volunteer leader in the group and (2) including the possibility of communication. Results showed communication produced a significant increase in heroism and in group harvest, resulting from better management of the pool. The presence of a leader in a group had no overall effect on group performance. The implications of these findings for current resource management crises are discussed.     

Egg survival,embryonic development,and larval characteristics of northern shrimp (<Emphasis Type="Italic">Pandalus borealis</Emphasis>) females subject to different temperature and feeding conditions

Laboratory experiments on ovigerous females of northern shrimp (Pandalus borealis) were used to assess the effects of temperature and food ration on female condition during incubation and examine how combined effects of temperature and female condition influenced egg survival, embryonic development, and larval characteristics. Ovigerous females were maintained at 2°C, 5°C, and 8°C and fed on a low (three times/week; 2–2.7% W/W) or high ration (five times/week at satiation). The increase in temperature accelerated the developmental time of the eggs but their survival at 8°C was reduced. Conversion efficiency of yolk reserves in developing embryos was significantly reduced at elevated temperatures and larvae hatching at 2°C and 5°C were significantly larger and heavier than those hatching at 8°C. The experimental design did not result in any effect of food ration on the energetic condition of females or on egg characteristics and their biochemical composition. However, lower energy reserves were observed for females held at 8°C.