Aluminium in tea plantations: mobility in soils and plants, and the influence of nitrogen fertilization

The levels of extractable aluminum (Al) in soils of tea plantations, Al concentrations in tea leaves and the impact of nitrogen fertilization on these two parameters were investigated. In addition, the properties of soils from tea plantations were compared to those from soils of adjacent non-tea fields to evaluate the effect of land use conversion (from non-tea soils to tea soils). Exchangeable Al (extracted in 1 mol l⁻¹ KCl) ranged from 0.03 to 7.32 cmol_c kg⁻¹ in 94 tea fields and decreased rapidly with increasing soil pH. In comparison with non-tea soils, tea soils had a significantly lower pH and exchangeable Mg²⁺ concentration but higher organic matter contents and exchangeable K⁺ concentration. Contents of extractable Al were not different (P > 0.05) between these two soils. The concentrations of Al in mature tea leaves correlated significantly with exchangeable Al in soil samples taken at a depth of 20–40 cm and with exchangeable Al saturations in soil sampled at␣depths of 0–20 and 20–40 cm. In the pot experiment, nitrogen fertilization significantly increased extractable Al levels but decreased soil pH and the levels of exchangeable base cations. Nevertheless, the levels of Al in mature leaves and young shoots were significantly reduced by the application of large amounts of N fertilizer.     

环境实验室仪器设备期间核查研究

为了统一规范环境实验室仪器设备期间核查工作,分析了环境实验室仪器设备期间核查对象、主要内容、核查方法,提出了具体实施流程和结果处理方法.应加快期间核查相关标准的制定,以便统一规范环境仪器设备期间核查方法和要求,及时评价仪器设备的运行状态,增强检测数据的准确性,提高检测质量.     

Snort acoustic structure codes for positive emotions in horses

While the vocal coding of human and animal internal states has been widely studied, the possible acoustic expression of “positive” emotions remains poorly known. Recent studies suggest that snorts (non-vocal sounds produced by the air expiration through the nostrils) appear to be reliable indicators of positive internal states in several ungulate species. Here, we hypothesised in horses that the acoustic structure of the snort could vary with the subjects’ current emotional state. Indeed, a preliminary sound analysis of snorts let us suggest structure variations related to the presence of pulsations. We recorded snorts from 20 horses living in a riding center. Auditory playbacks run with 20 humans first confirmed the existence of two snort subtypes, i.e. one pulsed and one non-pulsed. Observations were then conducted to compare the distribution of these two subtypes according to the location (stall/pasture) of the signaller as a contextual determinant of its internal state and to its ears’ position as a reflection of its emotional state. We found that both subtypes were preferentially observed in positive contexts, but that pulsed snorts were even more associated with highly appreciated situations (in pasture and with ears forward). This study is a step further in the identification of indicators of positive emotions in horses and more generally in the understanding of the acoustic emotions’ coding.     

炼化企业实施职业健康监护项目与周期研究

从现行规范存在的问题入手,提出了确定炼化企业职业健康监护项目与周期的建议,旨在科学合理地指导炼化企业职业健康监护工作的运行操作。     

数字电视图像硬盘录像

本文从数字图像的特点引出图像讯号压缩技术,并介绍了不同压缩方式的特点及其最佳使用场合.同时引入统计概念来估算数字硬盘录像单位时间所需的平均容量和评估图像质量,为合理正确选用何种数字硬盘录像设备和选用何种工作方式提出了一些有益的看法.     

Exposure of children aged 0–7 years to perfluorinated compounds in Foshan,China

Environmental Science and Pollution Research - To evaluate the exposure of children to 14 perfluorinated compounds (PFCs) in a typical and representative industrial city, plasma samples from 476...     

Distribution characteristics and indicator significance of Dechloranes in multi-matrices at Ny-lesund in the Arctic

In recent years, Dechloranes have been widely detected in the environment around the world.However, understanding and knowledge of Dechloranes in remote regions, such as the Arctic,remain lacking. Therefore, the concentrations of 5 Dechloranes in surface seawater, sediment,soil, moss, and dung collected from Ny-lesund in the Arctic were measured with the concentrations 93 pg/L, 342, 325, 1.4, and 258 pg/g, respectively, which were much lower than those in Asian and European regions. The mean ratios of anti-Dechlorane Plus(DP) to total DP(fanti) in seawater, sediment, soil, moss, dung, and atmospheric samples were 0.36, 0.21, 0.18,0.27, 0.66, and 0.43, respectively. Results suggested that the main source of DP in seawater,sediment, soil, and moss was long-range atmospheric transport. However, the ratio identified in dung was different, for which the migration behavior of the organism is probably the main source of DP.     

环境监测实验室废液处理的讨论

环境监测作为环境保护工作的基础,并随着环境保护事业的发展而发展。近年来,我国环境监测水平大幅提高,监测能力不断增强,但随着工作量的加大,环境监测实验室所产生的废物数量及种类都在增多,这些废物如不经无害化处理直接排放,将会严重危及人们的健康。本文从防止污染环境的立场出发,分类讨论了环境监测实验室日常产生的废液处理方法。     

沈阳商业城火灾及灾后修复

介绍了发生在沈阳商业城的火灾及灾后调查、检测和加固情况，从中得到一些有意义的看法。