放射性核素在海水、底质及海洋生物间的转移--Ⅲ.核素在生物体内分布的生态学意义

本文是放射性核素在海水、底质及海洋生物间转移规律研究的第三部分,着重研究~(137)Cs、~(134)Cs、~(65)Zn、~(60)Co、~(59)Fe、~(54)Mn在毛蚶、文蛤、对虾、罗非鱼各主要组织器官中的分布,并计算各自的富集系数,同时也考察了各种核素在生物各个组织器官中的排出、在底质中的解吸作用以及生物再利用的过程.结果表明肠道和内脏对核素的富集量高,排出也快;外壳、鳃甚至肌肉对核素的富集量低,排出也慢.文中着重讨论了肠道、外壳、鳃在不同情况下成为生物体参与外界环境核素循环主要通道的生态学意义.     

Temporal and spatial variations of low-molecular-weight organic acids in Dianchi Lake, China

Low-molecular-weight organic acids (LMWOAs) in eutrophic lake water of Dianchi, Southwestern China Plateau were investigated diurnally and vertically using ion chromatography. Two profiles (P1 and P2) were studied due to the difference of hydrochemical features. Lactic, formic, pyruvic and oxalic acid were detected as major components at P1 and P2 which were on average 7.98 and 6.53 mol/L, respectively, corresponding to their proportions of 2.68% and 2.48% relative to DOC. Pyruvic acid was regarded as the uppermost species at P1 and P2, reaching up to 3.82 and 3.35 mol/L and accounting for 47.9% and 51.3%, respectively, in individual TOA. Although humus were of biogenetic production at both sites, the significant negative correlation between diurnal variations of TOAs, fluorescence intensity (FI) of protein-like components and humic-like components at P1 indicated LMWOAs were greatly originated from bacterioplankton excretion and degradation. However, correlations between diurnal variations of humic-like FI and physicochemical parameters demonstrated algal origination of LMWOAs at P2. Although content of humus was high, TOA at P2 was 1.45 mol/L lower than that at P1, due to the co-influence of more intense photo-oxidation and aggregation at P2. Therefore, TOAs exhibited quite opposite diurnal variation trends of increasing-decreasing and decreasing-increasing at P1 and P2, respectively. Except for impact of solar radiation, bacterial decomposition and assimilation rendered shifts of maximal LMWOAs along water column at P1. Covering with massive algae, UV rays penetrated shallower depth that LMWOAs assembled in surface layer water before 18:00 at P2 and represented decreasing profiles.     

地震工作者的公平意识研究

本文对地震系统高、中、初级专业人员的公平意识作了研究。运用量化标度数值处理,约90%的人属公平感范畴。解析公平感构成的直接主导因素和附加影响因素发现,良好感觉与岗位层次具有一致性,与他人比较、与过去比较“一样”的感觉呈稳定相态,投入和获得的关系表现出复杂的位错现象,事业信念向消极转化的倾向明显。对数值标度大于-1.5σ的非公平感者追访调查,证实确有其困难或问题。