Nutrient dynamics between sediment and overlying water in the inner part of Izmir Bay, Eastern Aegean

In this article a concept is described in order to predict and map the occurrence of benthic communities within and near the German Exclusive Economic Zone (EEZ) of the North Sea. The approach consists of two work steps: (1) geostatistical analysis of abiotic measurement data and (2) calculation of benthic provinces by means of Classification and Regression Trees (CART) and GIS-techniques. From bottom water measurements on salinity, temperature, silicate and nutrients as well as from punctual data on grain size ranges (0–20, 20–63, 63–2,000 μ) raster maps were calculated by use of geostatistical methods. At first the autocorrelation structure was examined and modelled with help of variogram analysis. The resulting variogram models were then used to calculate raster maps by applying ordinary kriging procedures. After intersecting these raster maps with punctual data on eight benthic communities a decision tree was derived to predict the occurrence of these communities within the study area. Since such a CART tree corresponds to a hierarchically ordered set of decision rules it was applied to the geostatistically estimated raster data to predict benthic habitats within and near the EEZ.     

Ambient nitrogen oxides exposure and early childhood respiratory illnesses

Acute respiratory infections are common in children below 5 years and recent studies suggest a possible link with air pollution. In this study, we investigated the association between ambient nitrogen oxides (NO_x) and bronchitis or upper airway inflammation.This longitudinal study was conducted in Teplice and Prachatice districts, Czech Republic. Children were followed from birth to 4.5 years of age. Data were compiled from medical records at delivery and at follow up, and from self-administered questionnaires from the same two time points. Air pollution monitoring data were used to estimate exposure over five different averaging periods ranging from three to 45 days prior to an episode. To quantify the association between exposure and outcome, while accounting for repeated measure correlation we conducted logistic regression analysis using generalized estimating equations.During the first 2 years of life, the adjusted rate ratio for bronchitis associated with interquartile increase in the 30-day average NO_x was 1.31 [95% confidence interval (CI): 1.07, 1.61] and for two to 4.5 year olds, it was 1.23 (95% CI: 1.01, 1.49). The 14-day exposure also had stable association across both age groups: below 2 years it was 1.25 (95% CI: 1.06, 1.47) and for two to 4.5 years it was 1.21 (95% CI: 1.06, 1.39). The association between bronchitis and NO_x increased with child's age in the under 2 years group, which is a relatively novel finding.The results demonstrate an association between NO_x and respiratory infections that are sufficiently severe to come to medical attention. The evidence, if causal, can be of public health concern because acute respiratory illnesses are common in preschool children.     

Seasonal and spatial variability of Po,U and Pu levels in the river catchment area assessed by application of neural-network based classification

The present study deals with the application of self-organizing maps (SOM) in order to model, classify and interpret seasonal and spatial variability of ²¹⁰Po, ²³⁸U and ^239+240Pu levels in the Vistula river basin. The data set represents concentration values for 3 alpha emitters (²¹⁰Po, ²³⁸U and ^239+240Pu) measured in surface water samples collected at 19 different sampling locations (8 in major Vistula stream while 11 in right or left Vistula tributaries) during four seasons (winter, spring, summer and autumn) in the framework of a one-year quality monitoring study. The advantages of an SOM algorithm, its classification and visualization ability for environmental data sets, are stressed. The neural-network based classification made it possible to reveal specific patterns related to both seasonal and spatial variability. In the middle and upper part of Vistula catchment as well as in the right-shore tributaries, concentrations of ²¹⁰Po and ²³⁸U during summer and winter are the lowest. Concentrations of ²¹⁰Po and ²³⁸U increase significantly during spring and autumn in the Vistula river catchment, especially in the delta of Vistula river. High concentration of anthropogenic originated ^239+240Pu indicates “site-specific” character of pollution in two large left-shore tributaries located in the middle part of the Vistula drainage area. Efficient classification of sampling locations could lead to an optimization of river radiochemical sampling networks and to a better tracing of natural and anthropogenic changes along Vistula river stream.     

地质灾害专题地图编制研究

地质灾害专题制图是地质灾害系统研究成果的高层次综合。本文论述了地质灾害制图的目的、原则、特点、表示内容与方法,为规划决策提供地质灾害背景图件。     

亚临界机组锅炉锅筒缺陷统计及检验建议

锅简作为亚临界机组锅炉的重要部件,及时检验发现其存在缺陷并进行控制处理是保证机组安全稳定运行的重要条件。在收集汇总了近百台300MW级别亚临界机组锅炉的检验结果的基础上,对锅简缺陷的出现比例进行了分类统计。检验人员在编制锅筒的检验方案时,参考该统计结果,可提高检验的缺陷检出率及时效性。     

湿地序列监测图像的地物目标分类方法

针对固定观测站采集的序列图像中光照变化和背景复杂的问题,将图像序列作为图像在时间维的拓展,提出一种结合颜色空间变换和神经网络的目标分类方法,以辽河口湿地为例开展实地观测试验。基于前期现场调查得到的地物分布信息,将序列图像转换至HSV空间,选择像素小区域作为样本训练多层神经网络,获得更高维度分类依据映射,并完成潮滩生态监测区域目标分类及重要湿地植物翅碱蓬的分布信息提取。对提取结果进行定量验证,该方法整体精确率稳定在90%左右。     

Environmental Water-Quality Zones for Streams: A Regional Classification Scheme

Various approaches have been used to classify large geographical areas into smaller regions of similar water quality or extrapolate water-quality data from a few streams to other unmonitored streams. A combination of some of the strengths of existing techniques is used to develop a new approach for these purposes. In this new approach, referred to here as SPARTA (SPAtial Regression-Tree Analysis), environmental characteristics for each monitored stream are first quantified using a Geographic Information System (GIS) and then regression-tree analysis is used to determine which characteristics are most statistically important in describing the distribution of a specific water-quality constituent. GIS coverages of only the most statistically significant environmental characteristics are then used to subdivide the area of interest into relatively homogeneous environmental water-quality zones. Results from the regression-tree analysis not only define the most important environmental characteristics, but also describe how to subdivide the coverage of the specific characteristic (for example, areas with <26% or ≥26% soil clay content). The resulting regionalization scheme is customized for each water-quality constituent based on the environmental characteristics most statistically related to that constituent. SPARTA was used to delineate areas of similar phosphorus, nitrogen, and sediment concentrations (by including land-use characteristics) and areas of similar potential water quality (by excluding land-use characteristics). The SPARTA approach reduced the variability in water-quality concentrations (phosphorus, total nitrogen, Kjeldahl nitrogen, and suspended sediment) within similarly classified zones from that obtained using the US Environmental Protection Agency's nutrient ecoregions.     

Validation of the Polish version of the World Health Organization Disability Assessment Schedule (WHODAS 2.0) in an elderly population (60–70 years old)

Purpose. To assess the reliability and validity of the Polish version of the 36-point World Health Organization Disability Assessment Schedule (WHODAS 2.0) in an elderly population. Method. One thousand randomly selected individuals, aged 60–70 years, living in south-eastern Poland were assessed using the Polish version of the WHODAS 2.0. Results. The analysis confirmed the high reliability and validity of the tool. Cronbach’s α index was 0.89. The tool had high stability, and the correlation between test and retest results was high. The relevance of the domain selection was high or very high. A factor analysis confirmed the relevance of assigning questions to domains. High theoretical relevance was also demonstrated. Statistically significant differences between those who were and were not suffering from health problems were observed. An analysis of the internal structure of the WHODAS 2.0 revealed strong correlations between the components of each domain and the final result. Conclusion. The Polish version of the WHODAS 2.0 showed high reliability and validity; thus, it can be used to assess health, functioning and disability in the elderly population of Poland.     

玄武湖沉积物中磷的形态分布特征

利用分级提取法分析了玄武湖的沉积磷形态,在玄武湖沉积物中,铝结合态磷的含量较低,平均值为64 mg/kg,其余形态磷中,铁结合态磷为241 mg/kg,有机磷为335 mg/kg,钙结合态磷为394 mg/kg.在环境变化的条件下,铁结合态磷可以释放到间隙水和上层水体中,是湖泊产生富营养化的重要因素;铝结合态磷由于含量少,对湖泊富营养化影响很小;钙结合态磷相对稳定且很难被生物利用,对湖泊富营养化影响不大;有机磷对水体有机负荷影响较大,并影响水体富营养化程度.     

基于遥感影像的2019—2020年盐城市生态保护红线区人类活动动态分析

以盐城市生态保护红线区为研究对象,选用哨兵-2号卫星遥感影像进行目视解译及变化斑块提取,分析其区域内2019-2020年人类活动的变化趋势.结果显示,动态变化情况分为正变化和逆变化,其中逆变化占变化总面积的绝大部分,主要呈现为水田的减少;正变化主要呈现为农村居民点的拆除.总体来说,人类活动变化面积非常少,无工业用地的增...