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991.
992.
分析了当前开发建设项目环境影响评价报告编制中存在的百科全书式大而全的资料堆砌式报告、片面追求脱离实际要求的技术先进性、报告编写不规范等问题,明确指出实用性是环境影响评价的根本属性,坚持实用性才能发挥环境影响评价的作用.  相似文献   
993.
We present a methodology for testing and applying a regional baseline for carbon (C) emissions from land-use change, using a spatial modelling approach (hereafter called the Climafor approach). The methodology is based on an analysis of causal factors of previous land-use change (Castillo et al. 2005). Carbon risk matrices constructed from the spatial correlation analysis between observed deforestation and driving factors (Castillo et al. 2005), are used to estimate future carbonemissions within acceptable limits for a forest conservation project. The performance of two risk matrices were tested by estimating carbon emissions between 1975 and 1996 from randomly selected sample plots of sizes varying from 1,600 to 10,000 ha and comparing the results of the observed emissions from these sample plots with the model estimations. Expected emissions from continued land-use change was estimated for the community applying the risk matrices to the current land cover. The methodology provides an objective means of constructing baseline scenarios including confidence intervals, using the sum of variances of the various data sources, such as measured carbon densities, classification errors, errors in the risk matrices, and differences between the model prediction and observed emissions of sample plots due to sample size. The procedures applied in this study also give an indication of the impact of the variance in the various data sources on the size of the confidence intervals, which allows project developers to decide what data sources are essential to improve his baseline. The modelling approach to estimate the deforestation pattern is based on readily available cartographic and census data, whereas data on carbon densities are required to assess the potential for forest conservation projects to offset carbon emissions.  相似文献   
994.
Passerine migrants require light from the blue-green part of the spectrum for magnetic compass orientation; under yellow light, they are disoriented. European robins tested under a combination of yellow light and blue or green light showed a change in behavior, no longer preferring their seasonally appropriate migratory direction: in spring as well as in autumn, they preferred southerly headings under blue-and-yellow and northerly headings under green-and-yellow light. This clearly shows that yellow light is not neutral and suggests the involvement of at least two types of receptors in obtaining magnetic compass information, with the specific interaction of these receptors being rather complex.  相似文献   
995.
酞酸酯类有机毒物在土壤中降解规律的研究   总被引:24,自引:4,他引:24  
研究了酞酸酯DEHP和DBF二种增塑剂在土壤中降解规律,结果表明:土壤中DEHP和DBP的降解速率可以用一级动力学方程描述,不同类型土壤对酞酸酯的降解能力是有所差别的,DBP在土壤中比DEHP容易降解,土壤灭菌后,降解能力明显降低,按种接解微生物后,土壤中DEHP降解速率明显加快,土壤含水量和温度影响DEHP和DBP的降解速率;本试验从土壤中分离出降解DEHP的细菌9株和真菌11株。  相似文献   
996.
程海微囊藻毒素的结构分析   总被引:2,自引:0,他引:2  
从中国云南程海湖获得的“水华”藻类样品中分离得到具有肝毒性的微囊藻毒素,用NMR,MS等多种结构分析手段鉴定,证明主毒素是一种环状七肽,含有Adda,β-Masp,Mdha和Glu各一分子以及2个Arg残基。相对分子质量1038即为Microcystin-RR。进一步利用二维核磁共振技术测定发现此毒素有两部分,它们是同分异构体,区别仅在于Adda上的2个双键的构型差异。  相似文献   
997.
998.
The kinetics of the reaction of dissolved S(IV) with H2O2 was studied on 59 precipitation samples collected in Southwestern China, during the period of June 1988 to October 1989, from which the oxidation rates of the reaction were measured. The extent of reaction was followed by continuous amperometric measurement of the concentrations of the reagents. The two systems (i. e. rainwater and purified water) have been studied with the same methodology under identical reaction conditions (e. g. reagent concentrations, ionic strength and temperature). The kinetics was studied in no buffer solutions. The effect of formaldehyde on the reaction has also been studied, including kinetic studies in laboratory and model calculations, and it is indicated that formaldehyde with typical atmospheric concentration exerts no influence on the reaction of dissolved S(IV) with H2O2. In addition, the activation energy of the reaction was also measured in purified water as reaction medium for temperature range 0-50℃ at pH 4.0  相似文献   
999.
1000.
本文根据船舶防污监督管理的内容、特点,系统地提出了船舶·违章排污造成污染事故的调查取证程序、方法、内容、综合分析方法.还阐述了作出处罚决定的内容,防治措施的要求和依法处罚的原则.  相似文献   
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