水生生物辐射剂量率计算在核电厂环境影响评价中的应用

生物辐射剂量率的计算是评价放射性元素对生物辐射影响的前提,也是核电厂环境影响报告书中不可缺少的组成部分。通过一个环境影响报告实例,介绍水生生物辐射剂量率的计算在核电厂环境影响评价中的应用。     

流域水质目标管理的AIZ量化分配技术

“分配影响区”（AIZ）概念是对传统混合区概念及其应用的一次重要补充和修正.它以保持水生态完整性为目的,将分配的概念引入对混合区的管理.AIZ过程涉及的“相对环境价值”、“保护水平”和“毒性质量”等重要概念需要多学科共同研究确定,也是分配过程的关键.在详细介绍了AIZ制定过程的基础上,以大宁河为例说明分配计算过程.采用基于毒性质量的分配方法,结合相关文献资料确定水体用途区和有关参数,计算出各用途区内AIZ的允许面积,该面积即为水体中各排放允许的影响区域.最后给出计算结果说明和管理应用,认为该分配结果要严于一般的“混合区”规定.同时认为该方法是对水体进行综合、量化管理的一个有效手段.      

Indigenous land rights and deforestation: Evidence from the Brazilian Amazon

Concerns over the expropriation of and encroachment on indigenous communities' lands have led to greater formalization of these communities' rights in a number of developing countries. We study whether formalization of indigenous communities' land rights affects the rate of deforestation in both the short and medium terms. Beginning in 1995, the Government of Brazil formalized the rights of several hundred indigenous communities whose lands cover more than 40 million hectares in the Amazon region and provided support for these rights’ enforcement. We study the program's impacts using a long time-series of satellite-based forest cover data. Using both plausibly exogenous variation in the timing of formalization and matched samples of treated and comparison communities, we find no effect of these protections on satellite-based greenness measures. This is true even for communities that received support for surveillance and enforcement of these rights. Notably, we observe low counterfactual rates of deforestation on communities' lands between 1982 and 2010, suggesting that indigenous land rights programs should not uniformly be justified on the basis of their forest protection, at least in the medium term.     

Global environmental assessments: Impact mechanisms

Many impacts of Global Environmental Assessment (GEA) processes on policy processes, and the mechanisms underlying these impacts, remain underappreciated. In this research, we focus on the 5th Global Environment Outlook and the Working Group III contribution to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Based on the perception of GEA process participants, we describe the mechanisms through which assessments create or alter interpersonal interactions which can affect the dissemination of ideas. In particular, we find that GEAs can contribute to framing international coordinative discourses in intergovernmental negotiations. This can be achieved by widening, improving and/or maintaining the active participation of policy actors in the discussions of global environmental risks and by creating the scientific foundations for intergovernmental negotiations. GEAs can also contribute to national coordinative discourses by facilitating reflexive learning amongst participants, empowering them to diffuse and translate global information, and by providing methodological guidance. They can contribute to national communicative discourses by reviving interest and awareness of the urgency to address environmental problems. In this way they provide powerful arguments for governmental societal actors to challenge or strengthen existing national coordinative discourses. Finally, GEAs can improve scientific discourses worldwide by enhancing the capacity of individual researchers to produce and communicate relevant research insights. This is achieved by participating in a learning exercise with an extended community of peers and policy actors. This article is part of a special issue on solution-oriented global environmental assessments.     

城市快速路景观影响评价方法探讨

首先介绍了国内外道路景观影响评价发展状况和意义,给出了城市快速路景观及视觉影响评价的基本概念、步骤和方针;结合常用的景观影响评价方法,充分考虑工程实践中时间性、准确性要求形成了一套具有较强操作性的景观影响评价方法。在该方法中对指标的概念和标准化处理方法做了改进,计算函数更为实用和完备,并充分考虑了公众关注度的因素,体现了观念的更新。最后给出了对视觉影响的缓解措施和改进意见。     

总结经验进一步做好环境影响评价工作

介绍了建设项目环境影响评价的主要内容 ,编制环境影响报告书应该注意的问题 ,同时对今后如何进一步做好环境影响评价工作提出了几点具体意见。     

斜楔式槽钢冲孔模

介绍了斜楔式槽钢冲孔模的结构与工作原理,以及凸模、双向斜楔、退料组件等主要零部件的设计技术方法.     

Cytogenetic prenatal diagnosis and its relative effectiveness in the mersey region and North Wales

The relative effectiveness of cytogenetic prenatal diagnosis in the Mersey Region and North Wales is presented by estimating the percentage detection rates of Down's syndrome annually following amniocentesis from 1978–1984 inclusive. Tables indicating the percentage of screened pregnancies, types of chromosomal aberrations detected and the occurrence of Down's syndrome in mothers in age groups of five-year intervals are also presented. The average prenatal detection rate for Down's syndrome (estimated at the time of birth) was 15–15 per cent over the years 1978–1984 and was above 22 per cent for the last two years when 44–13 per cent of all pregnancies to mothers of 35 years and over were investigated.     

稻田甲烷排放及其生态效益提高途径的探讨

甲烷被认为是仅次于ＣＯ＿２的具有温室效应的气体．在农业生态系统中，稻田是甲烷的主要来源．讨论稻田甲烷排放量、排放机制，提出减少稻田甲烷排放的控制措施，对控制稻田生态效益提供依据．此外，本文结合稻田生态效益提高途径进行科学认识．     

浅谈乡镇工业环境管理及防治对策

就新城子区乡镇工业环境影响现状进行了论述和分析，阐明了乡镇工业污染的特点，提出了控制和防治乡镇工业污染，保护农村环境质量与生态平衡的措施和对策