东洞庭湖湿地生态系统健康状态与水位关系研究

基于CBERS卫星遥感影像数据,以东洞庭湖国家级自然保护区为研究区,通过光谱特征分析建立决策树分类模型,提取东洞庭湖湿地的地物类型。以生态系统健康理论为基础,依据东洞庭湖湿地的特点,综合湿地生产力、组织结构、弹性和功能4个方面,建立湿地生态系统健康状态评价指标体系和评价模型,利用GIS技术,分析东洞庭湖湿地在2000～2006年10个时相的生态系统健康状态。结合城陵矶水文站的水位数据,探讨了东洞庭湖湿地健康状态与城陵矶水位之间的相关性,并利用2007年两个时相的数据进行检验。研究结果表明：东洞庭湖湿地健康状态与城陵矶水位之间存在着较大的相关性,当城陵矶水位达到30 m左右时,东洞庭湖湿地健康状态达到最佳值     

Appraisal of water matrix on the removal of fungicide residues by heterogeneous photocatalytic treatment using UV-LED lamp as light source

Environmental Science and Pollution Research - In this study, the photocatalytic degradation of four fungicides, myclobutanil, penconazole and difenoconazole (triazole compounds) and boscalid...     

Dimethoate induces genotoxicity as a result of oxidative stress: in vivo and in vitro studies

Environmental Science and Pollution Research - Dimethoate ([O,O-dimethyl S-(N-methylcarbamoylmethyl) phosphorodithioate]) is an organophosphate insecticide and acaricide widely used for...     

Environmental and socioeconomic assessment of impacts by mining activities—a case study in the Certej River catchment,Western Carpathians,Romania

Background, aim and scope

In the region of the Apuseni Mountains, part of the Western Carpathians in Romania, metal mining activities have a long-standing tradition. These mining industries created a clearly beneficial economic development in the region. But their activities also caused impairments to the environment, such as acid mine drainage (AMD) resulting in long-lasting heavy metal pollution of waters and sediments. The study, established in the context of the ESTROM programme, investigated the impact of metal mining activities both from environmental and socioeconomic perspectives and tried to incorporate the results of the two approaches into an integrated proposition for mitigation of mining-related issues.

Study site

The small Certej catchment, situated in the Southern Apuseni Mountains, covers an area of 78 km². About 4,500 inhabitants are living in the basin, in which metal mining was the main economic sector. An open pit and several abandoned underground mines are producing heavy metal-loaded acidic water that is discharged untreated into the main river. The solid wastes of mineral processing plants were deposited in several dumps and tailings impoundment embodying the acidic water-producing mineral pyrite.

Methods

The natural science team collected samples from surface waters, drinking water from dug wells and from groundwater. Filtered and total heavy metals, both after enrichment, and major cations were analysed by inductively coupled plasma optical emission spectroscopy (ICP-OES). Major anions in waters, measured by ion chromatography, alkalinity and acidity were determined by titration. Solid samples were taken from river sediments and from the largest tailings dam. The latter were characterised by X-ray fluorescence and X-ray diffraction. Heavy metals in sediments were analysed after digestion. Simultaneously, the socioeconomic team performed a household survey to evaluate the perception of people related to the river and drinking water pollution by way of a logistic regression analysis.

Results and discussion

The inputs of acid mine waters drastically increased filtered heavy metal concentrations in the Certej River, e.g. Zn up to 130 mg L⁻¹, Fe 100 mg L⁻¹, Cu 2.9 mg L⁻¹, Cd 1.4 mgL⁻¹ as well as those of SO₄ up to 2.2 g L⁻¹. In addition, river water became acidic with pH values of pH 3. Concentrations of pollutant decreased slightly downstream due to dilution by waters from tributaries. Metal concentrations measured at headwater stations reflect background values. They fell in the range of the environmental quality standards proposed in the EU Water Framework Directive for dissolved heavy metals. The outflow of the large tailing impoundment and the groundwater downstream from two tailings dams exhibited the first sign of AMD, but they still had alkalinity.

Most dug wells analysed delivered a drinking water that exhibited no sign of AMD pollution, although these wells were a distance of 7 to 25 m from the contaminated river. It seems that the Certej River does not infiltrate significantly into the groundwater.

Pyrite was identified as the main sulphide mineral in the tailings dam that produces acidity and with calcite representing the AMD-neutralising mineral. The acid–base accounting proved that the potential acid-neutralising capacity in the solid phases would not be sufficient to prevent the production of acidic water in the future. Therefore, the open pits and mine waste deposits have to be seen as the sources for AMD at the present time, with a high long-term potential to produce even more AMD in the future.

The socioeconomic study showed that mining provided the major source of income. Over 45% of the households were partly or completely reliant on financial compensations as a result of mine closure. Unemployment was considered by the majority of the interviewed persons as the main cause of social problems in the area. The estimation of the explanatory factors by the logistic regression analysis revealed that education, household income, pollution conditions during the last years and familiarity with environmental problems were the main predictors influencing peoples’ opinion concerning whether the main river is strongly polluted. This model enabled one to predict correctly 77% of the observations reported. For the drinking water quality model, three predictors were relevant and they explained 66% of the observations.

Conclusions

Coupling the findings from the natural science and socioeconomic approaches, we may conclude that the impact of mining on the Certej River water is high, while drinking water in wells is not significantly affected. The perceptions of the respondents to pollution were to a large extent consistent with the measured results.

Recommendations and perspectives

The results of the study can be used by various stakeholders, mainly the mining company and local municipalities, in order to integrate them in their post-mining measures, thereby making them aware of the potential long-term impact of mining on the environment and on human health as well as on the local economy.

     

Identification of perfluoroalkyl acid sources in Swiss surface waters with the help of the artificial sweetener acesulfame

Anthropogenic perfluorinated compounds (PFCs), especially the perfluoroalkyl acids (PFAAs) are ubiquitously found in surface waters around the globe. Emissions from households, industries and also atmospheric transport/deposition are discussed as the possible sources. In this study, these sources are evaluated using Switzerland as the study area. Forty-four surface water locations in different rivers and an Alpine lake were investigated for 14 PFAAs, four precursors and acesulfame, an artificial sweetener used as a population marker. Concentrations of individual PFAAs were generally low, between 0.02 and 10 ng/L. Correlation analysis showed that some PFAAs concentrations correlated well with population and less with catchment area, indicating that emissions from population, i.e., from consumer products, is the most important source to surface waters in Switzerland. The correlation with the population marker acesulfame confirmed this observation but highlighted also a few elevated PFAA levels, some of which could be attributed to industrial emissions.     

When creativity enhances sales effectiveness: The moderating role of leader–member exchange

This study extends research on creativity by exploring the boundary conditions of the creativity–job effectiveness relationship. Building on social exchange theory, we argue that the extent to which employee creativity is related to sales—an objective work effectiveness measure—depends on the quality of leader–member exchange (LMX). We hypothesize that the relationship between creativity and sales is significant and positive when LMX is high, but not when LMX is low. Hierarchical linear modelling analysis provided support for the interaction hypothesis in a sample of 151 sales agents and 26 supervisors drawn from both pharmaceutical and insurance companies. Results showed that sales agents who were more creative generated higher sales only when they had high‐quality LMX. An ad hoc qualitative study provided a more detailed understanding of the moderator role played by LMX. Copyright © 2012 John Wiley & Sons, Ltd.     

Improving ozonation to remove carbamazepine through ozone-assisted catalysis using different NiO concentrations

The carbamazepine (CBZ) abatement is herein evaluated using catalytic ozonation at different NiO concentrations as catalyst: 100, 300, and 500 mg      

Water quality assessment of the Tubarão River through chemical analysis and biomarkers in the Neotropical fish Geophagus brasiliensis

The Tubarão River rises in Santa Catarina, Brazil, and has been historically affected by coal mining activities around its springhead. To evaluate its water conditions, an investigation regarding a possible decontamination gradient associated with the increased river flow toward the estuary, as well as the influence of seasonality over this gradient was performed through a series of biomarkers (vitellogenin, comet assay, lipid peroxidation, protein carbonylation, gluthatione, gluthatione S-transferase, acetylcholinesterase, light microscopy in liver, and scanning electron microscopy in gills) and chemical analysis (polycyclic aromatic hydrocarbons (PAHs) in bile and metal analysis in sediment) in the cichlid Geophagus brasiliensis. Two collections (summer and winter) were made in four distinct sites along the river, while sediments were sampled between those seasons. As expected, the contamination linked exclusively to mining activities was not observed, possibly due to punctual inputs of contaminants. The decontamination gradient was not observed, although seasonality seemed to have a critical role in the responses of biomarkers and availability of contaminants. In the summer, the fish presented higher histopathological damages and lower concentrations of PAHs, while in the winter they showed both higher genetic damage and accumulation of PAHs. The Tubarão suffers impacts from diverse activities, representing health risks for wild and human populations.     

Multiresidue determination of carbamate,organochlorine, organophosphorus,and dicarboximide pesticides in lettuce by GC/MS

An extraction method based on matrix solid-phase dispersion was developed to determine pirimicarb, methyl parathion, malathion, procymidone, α -endosulfan and β -endosulfan in lettuce using gas chromatography-mass spectrometry. The best results were obtained using 4.0 g of lettuce, 2.0 g of silica as dispersant sorbent, 0.1 g of activated carbon as clean up sorbent and acetonitrile as eluting solvent. The method was validated using lettuce samples fortified with pesticides at six different concentration levels (0.1 to 2.0 mg/kg). Average recoveries (7 replicates) ranged from 50 to 120 %, with relative standard deviations between 0.6 and 8.0 %. Detection and quantification limits for lettuce ranged from 0.01 to 0.02 mg/kg and 0.04 to 0.10 mg/kg, respectively.