The effect of humic substances on Cu migration in the soil profile

Humic substances (HS) are widely used for diverse purposes. The effect of HS on the metal’s status in contaminated soils is contradictory. The aim of this work was to investigate the Cu migration in soils treated with HS. A model field experiment with the addition of Cu (1.243?mg?Cu/kg) and HS Extra® (potassium humate) was performed. The Cu addition resulted in acidification (by 0.7 pH) after 3 months. The major part of the added Cu remained in the upper 7-cm-thick soil layer; 4% reached the lower soil layer, while only 0.1% were removed beyond the profile. The addition of HS mitigated soil acidification increased the content of Cu bound to solid-phase organic substances and abruptly reduced the Cu activity in the soil liquid phase. Simultaneously, the HS addition increased the water-soluble organic substances (WSOS) by four times, including those in the hydrophilic and hydrophobic fractions, resulting in a twofold increase in the content of soluble Cu. Copper complexes with hydrophilic WSOS mainly reached lysimeters, and hydrophobic organic substances were absorbed by the soil. The HS addition to a slightly acidic soil can accelerate the migration of Cu to adjacent environments.     

环丙沙星(CIP)对鲤鱼早期生长阶段的影响

我们依据经济合作与发展组织的210指导性文件,利用鲤鱼受精卵,进行环丙沙星(CIP)的毒性试验。测试浓度设置为1、100、500、1 000和3 000 μg?L^L-1。我们发现在所有测试组中,暴露于CIP会加速孵化,但在暴露于最高浓度CIP(3000 μg?L^L-1)的测试组,出现了显著的生长下降的现象。在实验的第6天(孵化之后),可以观察到大量增加的肉眼可见的形态异常现象。最高数量肉眼可见的形态异常现象是在自由胚胎和幼虫CIP暴露浓度为100、500、1 000和3 000 μg?L^L-1的测试组中产生的(测试样本的20%~23%)。在所有CIP暴露试验组中,均检测出GST活性的呈逐步降低趋势,但是在CIP浓度为500和3 000 μg?L^L-1的测试组中出现了显著差异(p < 0.01)。其中在大多数测试浓度下,谷胱甘肽过氧化物酶和过氧化氢酶的活性增加(p < 0.01,p < 0.05),而在CIP暴露浓度为500和3 000 μg?L^L-1的测试组,谷胱甘肽还原酶出现活性降低的现象(p < 0.05)。在所有的CIP暴露组中,硫代巴比妥酸活性物质的浓度明显降低(p < 0.01)。可测的CIP最低有效浓度(LOEC)是1 μg?L^L-1。\这些结果表明,孵化过程,早期的个体发育,形态异常的产生,以及鱼类体内的抗氧化和生物转化酶活性和脂质过氧化反应,都会受到CIP影响。
精选自Dana Zivna, Lucie Plhalova, Lucie Chromcova, Jana Blahova, Miroslav Prokes, Misa Skoric, Petr Marsalek, Eva Praskova, Stanislava Stepanova, Zdenka Svobodova. The effects of ciprofloxacin on early life stages of common carp (Cyprinus carpio). Environmental Toxicology and Chemistry: Volume 35, Issue 7, pages 1733–1740, July 2016. DOI: 10.1002/etc.3317
详情请见http://onlinelibrary.wiley.com/doi/10.1002/etc.3317/full
     

State of the environment in the arrangement area of the enterprises for repairing and utilization of nuclear-powered submarines

The influence of nuclear-powered utilization (disjunction) upon the state of health of the soil, vegetation and atmospheric air was studied. It was stated that the concentration of hazardous metals in the air of an industrial site did not exceed the permissible levels. In the residential area the cases of increased concentrations of manganese and chromium were noted. The major pollutants of vegetation are manganese, titanium, copper and nickel. The authors propose a complex of anthropogenic factors to be the cause of the environmental contamination by hard metals. The volume activity of radioactive aerosols in the studied site is confined to the local hum.     

Impact of the Development of Hydrocarbon Deposits on Water Ecosystems of the Yamal Peninsula

Russian Journal of Ecology - Data of monitoring studies (2014–2016) on the state of hydrobionts in watercourses during the development of a hydrocarbon deposit on the Yamal Peninsula have...