A “multi-pollutant exposure programme” reflecting the new pollution situation where SO2 is no longer the dominating pollutant has been performed by the International Co-operative Programme on Effects on Materials,
including Historic and Cultural Monuments (ICP Materials) within the activities of the Convention on Long-range Transboundary
Air Pollution. The main results obtained in the period 1997–2003 are summarised. Dose-response functions are presented for
carbon steel, zinc, copper, bronze and limestone. Parameters involved in the functions include besides SO2 and pH, which were included in the previously developed functions from ICP Materials, also the effect of particulate matter
and HNO3. 相似文献
Wildlife managers are challenged with the task of deciding whether a management measure is appropriate or not, and furthermore they have to convince others about the merits of their decision. Population decline of some hare species (genus Lepus) has resulted in their Red Listing and conservation measures are being undertaken. Release or restocking is a frequent measure in some countries, and thousands of hares are released annually, mainly for hunting purposes. These hares can be obtained by either intensive or extensive rearing or translocation of the wild animals. Each method entails difficulties and different survival rates in the wild. Survival rates in the wild are low for hares intensively reared in cages but are higher for hares reared extensively in enclosures and wild translocated hares. The benefits of the hare release practice are significantly lower than the action’s implementation cost. Hare releases have not increased significantly the wild hare population or the hunting harvest in areas where the practice has been applied. The risk of genetic and evolutionary degradation and pathogen transmission is possible in wild populations. The need for wise management of this practice is evident and the term ‘Permitted Transferring Units’ should be introduced to denote regions where hares should not be transferred for rearing and release. 相似文献
Photosynthetic activity, oxidative stress, and Cu bioaccumulation in the seagrass Cymodocea nodosa were assessed 4, 12, 24, 48, and 72 h after exposure to two copper oxide nanoparticle (CuO NP) concentrations (5 and 10 mg L?1). CuO NPs were characterized by scanning electron microscopy (SEM) and dynamic light scattering measurements (DLS). Chlorophyll fluorescence analysis was applied to detect photosystem II (PSII) functionality, while the Cu accumulation kinetics into the leaf blades was fitted to the Michaelis-Menten equation. The uptake kinetics was rapid during the first 4 h of exposure and reached an equilibrium state after 10 h exposure to 10 mg L?1 and after 27 h to 5 mg L?1 CuO NPs. As a result, 4-h treatment with 5 mg L?1 CuO NPs, decreased the quantum yield of PS II photochemistry (ΦPSΙΙ) with a parallel increase in the regulated non-photochemical energy loss in PSII (ΦNPQ). However, the photoprotective dissipation of excess absorbed light energy as heat, through the process of non-photochemical quenching (NPQ), did not maintain the same fraction of open reaction centers (qp) as in control plants. This reduced number of open reaction centers resulted in a significant increase of H2O2 production in the leaf veins serving possibly as an antioxidant defense signal. Twenty-four-hour treatment had no significant effect on ΦPSΙΙ and qp compared to controls. However, 24 h exposure to 5 mg L?1 CuO NPs increased the quantum yield of non-regulated energy loss in PSII (ΦNO), and thus the formation of singlet oxygen (1O2) via the triplet state of chlorophyll, possible because the uptake kinetics had not yet reached the equilibrium state as did 10 mg L?1. Longer-duration treatment (48 and 72 h) had less effect on the allocation of absorbed light energy at PSII and the fraction of open reaction centers, compared to 4-h treatment, suggesting the function of a stress defense mechanism. The response of C. nodosa leaves to CuO NPs fits the “Threshold for Tolerance Model” with a threshold time (more than 4 h) required for induction of a stress defense mechanism, through H2O2 production. 相似文献
The objective of this study was to assess the contamination level of potentially harmful elements (PHEs) in industrial soils and how this relates to environmental magnetism. Moreover, emphasis was given to the determination of the potential mobile fractions of typically “technogenic” metals. Therefore, magnetic and geochemical parameters were determined in topsoils (0–20 cm) collected around a chemical industry in Sindos Industrial Area, Thessaloniki, Greece. Soil samples were presented significantly enriched in “technogenic” metals such Cd, Pb, and Zn, while cases of severe soil contamination were observed in sampling sites north-west of the industrial unit. Contents of Cd, Cr, Cu, Ni, Pb, Mo, Sb, Sn, and Zn in soils and pollution load index (PLI) were highly correlated with mass specific magnetic susceptibility (χlf). Similarly, enrichment factor (EF) and geoaccumulation index (Igeo) for “technogenic” Pb and Zn exhibited high positive correlation factors with χlf. Principal component analysis (PCA) classified PHEs along with the magnetic variable (χlf) into a common group indicating anthropogenic influence. The water extractable concentrations were substantially low, while the descending order of UBM (Unified BARGE Method) extractable concentrations in the gastric phase was Zn > Pb > As > Cd, yet Cd showed the highest bioaccessibility (almost 95%).
This study was designed to assess the effects of long term, high metal exposition (cadmium, lead, copper, nickel and zinc) on DNA damage in four plant model systems [Taraxacum officinale (Asteraceae), Matricaria recutita L. (Asteraceae), Robinia pseudoacacia L. (Fabaceae), and Urtica dioica (Urticaceae)]. DNA stability was investigated by a Random Amplified Polymorphic DNA (RAPD) technique. Agarose-gel electrophoresis revealed total of 37 bands with different molecular weights ranging from 1250 to 5000 bp. It generated distinctive polymorphism value of 72.97% (27 bands) total in four plant species investigated. The dendrogram constructed using NTSYSpc programme showed that there is grouping in separate clusters of the same plant model collected from two different areas (metal-exposed and control samples). The study concluded that the long term metal-exposing periods had genotoxic stress on macromolecules of plant model systems investigated and biomarkers used should be augmented for reliable estimates of genotoxicity after exposure of plants to metal stressors. 相似文献
This paper presents techniques for studying the influence of the climatic and other variables for the explanation of the water use with an example of time series in Gainesville, Florida. A statistical methodology is described for separating the different time scale components in time series of water use, namely, long term component, seasonal component, and short term component. We analyze each component separately and we prove that the temperature, precipitation, soil temperature, and relative humidity time series are the main climatic factors for the explanation of the long term, seasonal and short term component of the water use time series. Part of the residuals derived from the linear regression of the long term component of the water use can be explained by the unemployment rate. We also show that with the decomposition of the water use time series the explanation of the water use has been improved approximately two times. The explanation of the long term component of water use by the long term regional weather parameters can enable us to the long term regional prediction of the water resources availabilities. This methodology can be applied for studying the water use time series in other locations, as well. 相似文献
Measurement of air exchange rate provides critical information in energy and indoor-air quality studies. Continuous measurement of ventilation rates is a rather costly exercise and requires specific instrumentation. In this work, an alternative methodology is proposed and tested, where the air exchange rate is calculated by utilizing indoor and outdoor routine measurements of a common pollutant such as SO2, whereas the uncertainties induced in the calculations are analytically determined. The application of this methodology is demonstrated, for three residential microenvironments in Athens, Greece, and the results are also compared against ventilation rates calculated from differential pressure measurements. The calculated time resolved ventilation rates were applied to the mass balance equation to estimate the particle loss rate which was found to agree with literature values at an average of 0.50 h?1. The proposed method was further evaluated by applying a mass balance numerical model for the calculation of the indoor aerosol number concentrations, using the previously calculated ventilation rate, the outdoor measured number concentrations and the particle loss rates as input values. The model results for the indoors’ concentrations were found to be compared well with the experimentally measured values. 相似文献