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101.
The results of forest health status assessments in the Carpathian Mountains from the monitoring networks developed by the European Union Scheme on the Protection of Forest Against Atmospheric Pollution (EU Scheme) and International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP-Forests), have led to a better understanding of the impact of air pollution and other stressors on forests at the regional scale. During the period 1997-2001, forests in the Carpathian Mountains were severely affected by air pollution and natural stresses with 29.7-34.9% of the trees included in defoliation classes 2-4. The broadleaves were slightly healthier than the conifers, and European beech (Fagus sylvatica) was the least affected species. Norway spruce (Picea abies) has poor health status, with 42.9-46.6% of the trees damaged (2-4% defoliation classes). Silver fir (Abies alba) damage was also high, with 46.0-50.9% in defoliation classes 2-4. Pines (primarily Pinus sylvestris) were the least affected of the conifers, with 24.9-33.8% in defoliation classes 2-4. The results from the transnational networks (16 x 16 km) show that the Carpathian forests are slightly more damaged than the average for the entire Europe. The correlative studies performed in individual European countries show the relationships between air pollution stressors with trends in defoliation and a possible effect of natural stresses at each site. More specific, effects of tree age, drought, ozone and acid deposition critical level exceedances were demonstrated to affect crown condition.  相似文献   
102.
The absorption of Pb(II) ions from aqueous solution by di erent alginate compounds was studied in a batch sorption system. Water soluble sodium alginate and insoluble calcium alginate beads were investigated. The lead-binding capacity of both alginate compounds was highest within the pH range 6–8. The binding capacities and rates of Pb(II) ions by alginate compounds were evaluated. The Langmuir, Freundlich, and Bruneaur, Emmet and Teller (BET) sorption models were applied to describe the isotherms and isotherm constants. Sorption isothermal data could be well interpreted by the Langmuir model. The results obtained through the study suggest that alginate compounds are favorable sorbents. The largest amount of Pb(II) ions were bound by sodium alginate although the di erence between two compounds was slight. Therefore, alginate substances may be considered as an alternative for sorption and removal of Pb(II) ions from wastewaters.  相似文献   
103.
In this study,fog simulations were conducted using the Fifth-Generation NCAR/Penn State Mesoscale Model (MM5) in and around the Yodo River Basin,Japan.The purpose is to investigate the MM5 performance of fog simulation for long-term periods.The simulations were performed for January,February,March,and July,2005 with a coarse 3-kin and a nested fine 1-km grid domains. Results of the simulations were compared with data from ten meteorological observatories,fog sampling site in Mt.Rokko,and visibility measu...  相似文献   
104.
针对普遍采用的膜采样离线分析与在线测定大气细粒子中元素碳和有机碳的方法进行了比较分析. 2006年1月~2007年4月期间在北京大学校园内应用膜采样离线分析和在线分析分季节同时测定了PM2.5中元素碳(EC)和有机碳(OC),并将结果进行对比.结果显示,膜采样法测得的OC约为在线仪器测得的OC的2倍, 2种方法差别主要体现在对OC的测量上.不加平行板有机物扩散吸收管引入OC比较大的正误差,而加平行板有机物扩散吸收管又将引入OC的负误差,约10%.同时采用平行板有机物扩散吸收管和后置膜的离线分析方法同在线观测的结果具有比较好的一致性.  相似文献   
105.
The European bumblebee, Bombus terrestris, is an invasive eusocial species whose distribution is expanding greatly beyond its native range because numerous colonies are imported to or locally produced in non-native countries for pollination of agricultural crops. Closely related species exist in Japan where the unrestricted import and use of B. terrestris has resulted in the establishment of wild colonies. Laboratory studies previously showed that B. terrestris and Japanese native species can copulate and produce fertilized eggs. Although these eggs do not hatch, the interspecific mating can cause a serious reproductive disturbance to native bumblebees. In this study, we determined the frequencies of interspecies mating between B. terrestris males and native bumblebee queens in the wild on the islands of Hokkaido and Honshu by analyzing the DNA sequences of spermatozoa stored in spermathecae of native queens. We found that 20.2% of B. hypocrita hypocrita queens and 30.2% of B. hypocrita sapporoensis queens had spermatozoa of B. terrestris males in their spermathecae. Given that a Bombus queen generally mates only once in her life, such high frequencies of interspecific mating with B. terrestris pose serious threats to the populations of native bumblebees in Japan.  相似文献   
106.
We have discovered that HNO3 and related species are released from the TiO2 surface into air in the TiO2 photocatalytic oxidation of NO2 (1 ppm) under continuous UV light illumination (1 mW cm−2) by dehumidifying the outlet gas of the reaction and analyzing the recovered condensate liquid by ion chromatography. The origin of the HNO3 recovered in the dehumidifier could not be explained by a simple desorption of HNO3 overproduced on the TiO2 surface. The produced HNO3 must be activated on the TiO2 surface and causing the unidentified reaction.  相似文献   
107.
An intensive field survey, with 6-h measurement intervals, of concentrations of chemical species in particulate matter and gaseous compounds was carried out at coastal sites on the Sea of Japan during winter. The concentration variation of SO2(g) and HNO3(g) were well correlated, whereas the NH3(g) concentration variation had no correlation with those of SO2(g) and HNO3(g). The NH4 + (p)/non-sea-salt- (nss-)SO4 2 −(p) ratio in particulate matter was mainly affected by the location of the sampling site. One or more concentration peaks of nss-Ca2 + for survey period were observed. Backward trajectories analyses for the highest nss-Ca2 + concentration peaks showed some inconsistency in pathways. We consider that insufficient mixing of the atmosphere and/or insufficient time for the transported air pollutants to react with those discharged locally are the most likely explanations for the discrepancies between the measured products [HNO3][NH3] and the calculated values.  相似文献   
108.
Suspended particulate matter (SPM) and fine particulate matter (less than or equal to 2.5 μm: PM2.5) have generally been decreasing for the last decade in Tokyo, Japan. To elucidate the major cause of this decrease, the authors investigated the different trends of airborne particulates (both SPM and PM2.5 concentrations) by evaluating comparisons based on the location of the monitoring stations (roadside vs. ambient), days of the week (weekdays vs. Sundays), and daily fluctuation patterns (2002 vs. 2010). Hourly mean SPM and PM2.5 concentrations were obtained at four monitoring stations (two roadside stations, two ambient stations) in Tokyo, Japan. Annual mean concentrations of each day of the week and of each hour of the day from 2002 to 2010 were calculated. The results showed that (1) the daily differences in annual mean concentration decreased only at the two roadside monitoring stations; (2) the high hourly mean concentrations observed on weekdays during the daily rush hour at the two roadside monitoring stations observed in 2002 diminished in 2010; (3) the SPM concentration that decreased the most since 2002 was the PM2.5 concentration; and (4) the fluctuation of hourly concentrations during weekdays at the two roadside monitoring stations decreased. A decreasing trend of airborne particulates during the daily rush hour in Tokyo, Japan, was observed at the roadside monitoring stations on weekdays since 2002. The decreasing PM2.5 concentration resulted in this decreasing trend of airborne particulate concentrations during the daily rush hours on weekdays, which indicates fewer emissions were produced by diesel vehicles.
ImplicationsThe authors compared the trends of SPM and PM2.5 in Tokyo by location (roadside vs. ambient), days of the week (weekdays vs. Sundays), and daily fluctuation patterns (2002 vs. 2010). The high hourly mean concentrations observed at the roadside location during rush hour on weekdays in 2002 diminished in 2010. The SPM concentration that decreased during rush hour the most was the PM2.5 concentration. This significant decrease in the PM2.5 concentration resulted in the general decreasing trend of SPM concentrations during the rush hours on weekdays, which indicates fewer emissions were produced from diesel vehicles.  相似文献   
109.
The composition of polycyclic aromatic hydrocarbons (PAHs) in Lake Baikal water and adjacent air layer and PAH emission composition profiles of possible sources were investigated. Analysis of emission composition data showed that the source profiles could not be grouped by fuel type or pyrogenic/petrogenic origin. Because of the similarity of source PAH profiles, the drawing of 3D mixing diagrams was the only way to check whether some of the potential PAH sources were the true sources. The mixing diagrams showed that the sources of air pollution were paper mills and wood burning and that the sources of water pollution were coal-fired and oil-fired boilers. The common source for both air and water was only oil and petroleum products. To determine the locations of PAH sources, their contributions to air and water pollution were calculated and mapped. Based on the results, air and water were polluted from both local and regional sources. The location of the zone influenced by a particular source was conditioned by physical properties of source emission, direction of air/water flows that transfer PAHs and temperature differences between mixing air/water flows.  相似文献   
110.
In recent years, sludge generated in sewage treatment plants (STPs) and solid waste from livestock being utilized is useful for circulation of nourishment in farmlands as recycled organic manure (ROM). In this study, we determined the residue levels and patterns of 12 pharmaceutical products generated by human activity in the ROMs produced from human waste sludge (HWS), sewage sludge (SS), cattle manure (CM), poultry manure (PM), swine manure (SM) and horse manure (HM).The kind and number of pharmaceutical products detected in ROMs were different. Fluoroquinolones (FQs) were detected at high levels in HWS and SS samples. In addition, the detection frequency and concentration levels of sulfonamides (SAs) in PM and SM were high. Moreover, high concentrations of chlortetracycline (CTC) were found in only SM. These differences reflect specific adherence adsorption of the pharmaceutical products to different livestock and humans. Moreover, it was found that the concentrations of pharmaceutical products and fermentation levels of ROMs had significant positive correlation (r = 0.41, p = 0.024).When the fermentation test of ROM was conducted in a rotary fermentor in a lab scale test, the residue levels of pharmaceutical products decreased effectively except carbamazepine (CBZ). The rates of decrease were in the case of tetracyclines (TCs): 85-92%, FQs: 81-100%, erythromycine: 67%, SAs: 79-95%, trimethoprim: 86% and CBZ: 37% by 30 d. Pharmaceutical products that can be decomposed by fermentation process at the lowest impact of residual antibiotic activities may therefore be considered as environmentally friendly medicines.  相似文献   
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