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71.
The utilisation of Social Impact Assessment (SIA) in Iran is analysed in terms of its policy context and its application in practice. Five case studies where SIA was employed in conjunction with Environmental Impact Assessments (EIA) for agricultural development projects are evaluated. In addition, the performance of the policy context is assessed. This research revealed that there are legal and institutional constraints to the effective functioning of SIA in Iran, and that there are deficiencies in the operating guidelines. There were serious problems associated with the way SIA was undertaken in all five case studies. Recommendations to improve the policy framework for the conduct of SIA are made. The recommendations advocate for a higher profile of SIA within legislation, for social issues to have greater emphasis in official guidelines for the conduct of EIA and SIA, and for a range of measures to increase the professionalism of SIA practice.  相似文献   
72.
目前,相关环境标准中均未明确制定关于导热炉大气污染物的排放内容。因此,对于导热炉的大气污染排放,各环境管理及监测部门均没有统一的执行标准。本文从导热炉工作原理、污染物排放特点等方面进行了分析,对其执行标准提出了个人的观点。  相似文献   
73.
浅谈环境监测社会化的质量监管新思路   总被引:1,自引:0,他引:1  
分析了现阶段社会环境检测市场的发展现状及存在的问题,探讨了从环境检测上岗能力、专业技能再教育、从业履历和信用等方面对社会环境检测从业人员进行管理的必要性,提出在机构环境监测能力、检测人员结构流动性、仪器设备在用状态和更新频率、从事环境监测业务信用等方面建立评估机制,推动环境监测市场健康发展。  相似文献   
74.
By scoring the chromosome number of developing embryos, we show that the sex ratio bias of the African social spider Stegodyphus dumicola Pocock is the result of an overproduction of female embryos. Only 17% of 585 embryos sexed from 14 egg sacs were male, a significant departure from a 1:1 sex ratio. We also explored the possibility of direct control of the sex of individual offspring in this species by examining the variance in the number of males per sac and the spatial distribution of male and female embryos within the sacs. We postulated that a variance in the number of males per sac lower than binomial (i.e., underdispersed or precise sex ratios) or a non-random distribution of male embryos within the sacs would suggest direct control of the sex of individual offspring. We found that the variance in the number of males per sac was indistinguishable from binomial and significantly larger than expected under exact ratios. Likewise, the spatial distribution of male embryos within three sacs examined was no more clustered than expected by chance. The sex ratio biasing mechanism in this species, therefore, apparently only allows control of the mean sex ratio but not of its variance. We present randomization and Monte Carlo methods that can be applied to test for departures from a random spatial arrangement of male and female embryos in an egg mass and for departures from binomial or exact ratios when not all members of a clutch have been sexed. Received: 21 October 1998 / Received in revised form: 23 March 1999 / Accepted: 26 April 1999  相似文献   
75.
Encounter rate and task allocation in harvester ants   总被引:7,自引:0,他引:7  
As conditions change, social insect colonies adjust the numbers of workers engaged in various tasks, such as foraging and nest work. This process of task allocation operates without central control; individuals respond to simple, local cues. This study investigates one such cue, the pattern of an ant's interactions with other workers. We examined how an ant's tendency to perform midden work, carrying objects to and sorting the refuse pile of the colony, is related to the recent history of the ant's brief antennal contacts, in laboratory colonies of the red harvester ant, Pogonomyrmex barbatus. The probability that an ant performed midden work was related to its recent interactions in two ways. First, the time an ant spent performing midden work was positively correlated with the number of midden workers that ant had met while it was away from the midden. Second, ants engaged in a task other than midden work were more likely to begin to do midden work when their rate of encounter per minute with midden workers was high. Cues based on interaction rate may enable ants to respond to changes in worker numbers even though ants cannot count or assess total numbers engaged in a task. Received: 1 July 1998 / Accepted: 15 November 1998  相似文献   
76.
The Euroconference on Coastal Management Research held in San-Feliu de Guixols, Spain, in December 1997 brought together scientists from a great variety of disciplines in the natural and social sciences, in a search for modes of transdisciplinary cooperation in the context of integrated coastal management. During the conference the participants discussed which interactions among disciplines are required for different coastal issues. Discussion groups each focused on a particular type of coastal environment, characterized by a particular type and degree of development. The group discussions were inspired by background papers which were prepared for this purpose by invited speakers. A selection of these background papers were redrafted on the basis of the conference outcome, and are published in this issue of theJournal of Coastal Conservation. The reports of the discussion groups are published in a conference proceedings booklet issued by EMAPS (1998), the European Polar and Marine Sciences Secretariat. A synthesis of ideas on the challenge of transdisciplinarity, expressed during the discussion group sessions, is presented in this introduction. The statements reflect opinions or suggestions which received broad support from the participants; they should not be taken as proven knowledge.  相似文献   
77.
Dominance interactions affected patterns of non-reproductive division of labor (polyethism) in the eusocial wasp Mischocyttarus mastigophorus. Socially dominant individuals foraged for food (nectar and insect prey) at lower rates than subordinate individuals. In contrast, dominant wasps performed most of the foraging for the wood pulp used in nest construction. Social dominance also affected partitioning of materials collected by foragers when they returned to the nest. Wood pulp loads were never shared with nest mates, while food loads, especially insect prey, were often partitioned with other wasps. Dominant individuals on the nest were more likely to take food from arriving foragers than subordinate individuals. The role of dominance interactions in regulating polyethism has evolved in the eusocial paper wasps (Polistinae). Both specialization by foragers and task partitioning have increased from basal genera (independent-founding wasps, including Mischo-cyttarus spp.) to more derived genera (swarm-founding Epiponini). Dominance interactions do not regulate forager specialization or task partitioning in epiponines. I hypothesize that these changes in polyethism were enabled by the evolution of increased colony size in the Epiponini. Received: 8 December 1997 / Accepted after revision: 28 March 1998  相似文献   
78.
Abstract: The probability of persistence of many species of hibernating bats in the United States is greatly reduced by an emerging infectious disease, white‐nose syndrome (WNS). In the United States WNS is rapidly spreading and is associated with a psychrophilic fungus, Geomyces destructans. WNS has caused massive mortality of bats that hibernate. Efforts to control the disease have been ineffective. The culling of bats in hibernacula has been proposed as a way to break the transmission cycle or slow the spread of WNS. We formulated a disease model to examine the efficacy of culling to abate WNS in bat populations. We based the model dynamics on disease transmission in maternity roosts, swarms, and hibernacula, which are the arenas of contact among bats. Our simulations indicated culling will not control WNS in bats primarily because contact rates are high among colonial bats, contact occurs in multiple arenas, and periodic movement between arenas occurs. In general, culling is ineffective in the control of animal diseases in the wild.  相似文献   
79.
对北京市地面监测站点的CO浓度进行分析,探讨其浓度水平、变化趋势和时空分布特征。2014年春、夏、秋、冬四季北京市CO平均浓度分别为1.06、0.87、1.34、2.17 mg/m3。CO浓度均呈双峰型变化,第一个峰值出现在07:00-09:00,主要由交通早高峰的排放引起;第二个峰值出现在23:00左右,主要受交通晚高峰排放和夜间边界层高度降低的挤压效应的共同影响。从空间分布来看,全年整体呈现南高北低的分布特征,尤其是秋、冬季较为明显,体现了工业布局和区域传输对CO的影响。从全年来看,湿度对CO浓度的影响最大。对2014年冬季北京市的一次高CO浓度分析结果表明,此次过程是由本地排放和区域传输共同造成的,气象要素中地面气压对CO浓度影响最大。  相似文献   
80.
目前中国空气质量监测数据缺乏统一的数据采集及传输管理规范,导致数据集成困难,各监测网络间的数据无法充分共享,形成信息孤岛。该研究在深入分析中国环境空气质量监测数据采集与传输现状及问题的基础上,遵循已有的标准规定并结合实际业务需求,针对环境空气质量监测数据传输系统结构、通讯协议以及监测数据编码提出具有良好扩展性、通用性及规范化的设计方案,以期促进监测设备及系统集成工作的标准化,实现系统间信息数据高度集成,信息资源充分共享和互融互通,环境空气质量监测业务紧密互动。  相似文献   
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