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1.
A study of concentrations of sulfur dioxide (SO2) and suspended particulate matter (SPM) has been performed in Delhi. The monthly and seasonal variations of concentrations and winds are analyzed. The monthly mean SO2 concentrations were in the range of 16.15–34.44 μg m−3 and showed regular seasonal variations with the highest concentrations in winter and lowest in monsoon season. On the other hand, the monthly mean SPM concentrations reached the highest (465.68 μg m−3) in November and the lowest (150.07 μg m−3) in August. It was observed that high SO2 concentrations were generally associated with the wind blowing from WNW–NW directions, and the high SPM concentrations were usually related to the wind blowing from W–NW directions.  相似文献   

2.
The Industrial Pollution Control Association of Japan (IPCAJ) has conducted an air quality study. A brief summary has already appeared in previous papers. This set of data was not sufficiently analysed. This study attempts to examine the performance of the Positive Matrix Factorisation (PMF), a recently introduced technique in this field, on this multiple-site Kashima data set. The source apportionment study using the PMF model conducted for the Kashima data set identified six factors for each fine and coarse fraction. This result also seems to be appropriate, because spatial distribution and seasonal variation of the contributions for each emission source category could be explained reasonably. The PMF can analyse a data set that may be extracted from different populations, and it seems to be a powerful tool available for these kinds of complicated data sets.  相似文献   

3.
This paper evaluates environmental bubble policy using abatement cost curves drawn for different abatement measures in Jamshedpur region. Surveys were conducted to estimate industrial emissions of suspended particulate matter (SPM) from different emitting sources in the region, and the characteristics of the existing and alternative abatement devices for each emitting source. The abatement cost functions were developed and used to rank the abatement devices. An environmental bubble with its limit equal to the existing SPM emissions from all selected companies was developed. The abatement costs for the bubble were estimated from abatement cost curves with alternative and best available technologies. The estimated abatement costs were found to be less than those of the existing measures. It was also found that M/s TISCO alone can account for SPM emissions reductions in the selected group with less cost.  相似文献   

4.
The relationship between suspended particulate matter (SPM) and fungal spore was investigated in Seosan, a rural county along the west coast of Korea, in the spring of 2000. SPM concentrations in the air were 199.8 μg m−3 in the first Asian dust period (23–24 March), 249.4 μg m−3 in the second Asian dust period (7–9 April) and 98.9 μg m−3 in the non-Asian dust period (12–16 May), respectively. The majority of the total SPM were composed of coarse particles sized about 5 μm during the two Asian dust periods. Four molds genera grown from airborne fungal spores were identified in colonies grown from SPM samples taken during the Asian dust periods. All the genera found, Fusarium, Aspergillus, Penicillium and Basipetospora, are hyphomycetes in the division Deuteromycota. Morphologically, more diversified mycelia of hyphomycetes were grown on the sample captured from 1.1 to 2.1 μm sized SPM than on the other sized samples gathered in the dust periods. On the other hand, no mold was observed on the sample of 1.1–2.1 μm sized SPM in the non-Asian dust period. From these results, it seems evident that several sorts of fine sized fungal spores were suspended in the atmospheric environment of this study area during Asian dust periods.  相似文献   

5.
A linear programming model is developed to calculate optimum SPM abatements at different emitting sources of M/s Tata Steel to achieve the abatement limits for the environmental bubble with least cost. An environmental bubble with its limit equal to the sum of permitted SPM emissions at all the emitting sources of M/s Tata Steel is considered. The optimum SPM abatements at different emitting sources of M/s Tata Steel are calculated using the developed model for environmental bubble and two emission offsets of 2 MT and 4 MT. The possible intra-firm trading of SPM emission reductions among different emitting sources at M/s Tata Steel is discussed.  相似文献   

6.
The elemental uptake and distribution, in various parts of the admired herbal plant, Hypoxis hemerocallidea, the 'African potato' and its ability to accumulate elements in response to the growth soil quality are investigated. The total and exchangeable concentrations of twelve elements in the growth soils and their distribution in the roots, potato bulb and leaves of the plants grown under four different settings were compared. The typical concentrations of the twelve selected elements, in the bulb and leaves of the plant grown in a nursery pot (site 2) were (in microg g(-1)dry weight) Ca (8430 and 27075), Mg (2113 and 1566), Fe (66 and 150), Al (10 and 368), Zn (105 and 6.1), Mn (42 and 51), Cu (7.2 and 20.8), Ba (0.23 and 4.44), Co (0.20 and 0.42), As (2.05 and 24.56), Hg (0.92 and 1.82) and Cr (0.13 and 0.33). Except for Ca, Mg, Zn and Mn, the exchangeable cation concentrations in all the growth soils were low. Ca, Mg, Mn, Zn and As had bioaccumulation factors >1. Fe, Al and Co concentrations were high in the roots with little in the rest of the plant. High concentration of arsenic (approximately 13 microg g(-1) dry weight) with bioaccumulation factors of 7 and 20 were observed in the roots and leaves of the plant respectively (site 2), but the concentration of mercury in bulb was very low (0.92 microg g(-1) dry weight).  相似文献   

7.
- DOI: http:/dx.doi.org/10.1065/espr2005.06.262 Goal, Scope and Background The anthropogenic environmental emissions of chloroacetic acids and volatile organochlorines have been under scrutiny in recent years because the two compound groups are suspected to contribute to forest dieback and stratospheric ozone destruction, respectively. The two organochlorine groups are linked because the atmospheric photochemical oxidation of some volatile organochlorine compounds is one source of phytotoxic chloroacetic acids in the environment. Moreover, both groups are produced in higher amounts by natural chlorination of organic matter, e.g. by soil microorganisms, marine macroalgae and salt lake bacteria, and show similar metabolism pathways. Elucidating the origin and fate of these organohalogens is necessary to implement actions to counteract environmental problems caused by these compounds. Main Features While the anthropogenic sources of chloroacetic acids and volatile organochlorines are relatively well-known and within human control, knowledge of relevant natural processes is scarce and fragmented. This article reviews current knowledge on natural formation and degradation processes of chloroacetic acids and volatile organochlorines in forest soils, with particular emphasis on processes in the rhizosphere, and discusses future studies necessary to understand the role of forest soils in the formation and degradation of these compounds. Results and Discussion Reviewing the present knowledge of the natural formation and degradation processes of chloroacetic acids and volatile organochlorines in forest soil has revealed gaps in knowledge regarding the actual mechanisms behind these processes. In particular, there remains insufficient quantification of reliable budgets and rates of formation and degradation of chloroacetic acids and volatile organochlorines in forest soil (both biotic and abiotic processes) to evaluate the strength of forest ecosystems regarding the emission and uptake of chloroacetic acids and volatile organochlorines, both on a regional scale and on a global scale. Conclusion It is concluded that the overall role of forest soil as a source and/or sink for chloroacetic acids and volatile organochlorines is still unclear; the available laboratory and field data reveal only bits of the puzzle. Detailed knowledge of the natural degradation and formation processes in forest soil is important to evaluate the strength of forest ecosystems for the emission and uptake of chloroacetic acids and volatile organochlorines, both on a regional scale and on a global scale. Recommendation and Perspective As the natural formation and degradation processes of chloroacetic acids and volatile organochlorines in forest soil can be influenced by human activities, evaluation of the extent of this influence will help to identify what future actions are needed to reduce human influences and thus prevent further damage to the environment and to human health caused by these compounds.  相似文献   

8.
Australia and New Zealand share many historical and contemporary commonalities. These define five contemporary forest environmental frontiers—for First Nations peoples, between agriculture and forestry, in forest management, in urban and peri-urban environments, and in relation to climate change. In both countries, the First Nations frontier is expanding in scale and significance with those peoples’ rights to land and forests. Frontiers with agriculture and in forest management are longstanding but dynamic and as yet little realised in relation to the need for forest and landscape restoration. Both countries are highly urbanised, elevating the significance of the urban and peri-urban frontier, particularly in the context of climate change. In both countries, forests will be profoundly impacted by climate change and are central to mitigation and adaptation strategies. Experience within and intersections between the frontiers offer encouraging prospects for synergies and for learning between the two countries and more widely.  相似文献   

9.
Fine PM measurements: personal and indoor air monitoring   总被引:3,自引:0,他引:3  
This review compiles personal and indoor microenvironment particulate matter (PM) monitoring needs from recently set research objectives, most importantly the NRC published "Research Priorities for Airborne Particulate Matter (1998)". Techniques and equipment used to monitor PM personal exposures and microenvironment concentrations and the constituents of the sampled PM during the last 20 years are then reviewed. Development objectives are set and discussed for personal and microenvironment PM samplers and monitors, for filter materials, and analytical laboratory techniques for equipment calibration, filter weighing and laboratory climate control. The progress is leading towards smaller sample flows, lighter, silent, independent (battery powered) monitors with data logging capacity to store microenvironment or activity relevant sensor data, advanced flow controls and continuous recording of the concentration. The best filters are non-hygroscopic, chemically pure and inert, and physically robust against mechanical wear. Semiautomatic and primary standard equivalent positive displacement flow meters are replacing the less accurate methods in flow calibration, and also personal sampling flow rates should become mass flow controlled (with or without volumetric compensation for pressure and temperature changes). In the weighing laboratory the alternatives are climatic control (set temperature and relative humidity), and mechanically simpler thermostatic heating, air conditioning and dehumidification systems combined with numerical control of temperature, humidity and pressure effects on flow calibration and filter weighing.  相似文献   

10.
中国城市污水处理厂污泥处理、处置问题探讨分析   总被引:50,自引:12,他引:38  
明确了有关污泥处理、处置的术语和定义,通过对我国污水处理厂污水处理工艺与污泥处理、处置现状的调查分析,认为污水处理工艺与污泥处理和最终处置方式有关;同时对污水处理厂污泥处理、处置中土地利用问题和处理、处置费用问题进行探讨,并提出了相关建议.  相似文献   

11.
植物对氮、磷去除效果及克藻效应的研究   总被引:2,自引:0,他引:2  
于夏季,在实验室和莫愁湖现场,开展了苦草和美人蕉对氮、磷去除效果及克藻效应的研究,结果表明,无论是在现场还是实验室,苦草和美人蕉对总氮、总磷都有明显的去除效果,且随着时间的增加,去除率也随之增大。在实验与现场条件,美人蕉与苦草对总氮和总磷的去除率之间没有显著差异。苦草和美人蕉都对蛋白核小球藻和铜绿微囊藻两种藻类表现出显著的抑制作用,但在实验与现场条件下,美人蕉和苦草对两种藻类的抑制效应存在着显著差异,而对于藻种则二者均表现出一定的选择性抑制作用。  相似文献   

12.
Forest inventory and analysis: a national inventory and monitoring program   总被引:1,自引:0,他引:1  
Forests provide significant commodity and noncommodity values to the citizens of the United States. An important and substantial role in ensuring the continued health, productivity, and sustainability of these resources is a reliable and credible inventory and monitoring program. The Forest Inventory and Analysis (FIA) program of the US Forest Service has been monitoring and reporting on status, condition, and trends in the nation's forests for over 70 years and the Forest Health Monitoring (FHM) program for the last 11 years. Recent legislation included in the 1998 Farm Bill, along with efforts to integrate inventory and monitoring networks to deliver Criteria and Indicators of Sustainable Forests, are redefining the role and operation of the recently integrated FIA and FHM programs. This paper provides a brief history and a look at new directions for the enhanced FIA Program.  相似文献   

13.
Understanding what causes variability in the outcomes of common-pool resources management and governance has important policy implications for biodiversity conservation, in particular for the conservation of wild plants and animals subject to harvest. We report an exploratory study focusing on Amazonian river turtles as a common-pool resource under harvest-driven conservation and management efforts in Peru. Based on document analysis, literature review and a series of interviews, we describe the management program as a social process and identify the most important governance and management outcomes achieved (increased turtle abundance and benefits for harvesters, harvester formalization), factors hindering and facilitating the program implementation (four natural and three societal factors), and key governance actions behind the program outcomes (awareness and capacity building, crafting and enforcing rules). We then highlight the existing knowledge gaps and the needs and possible means to address particular risks related to turtle management on a harvest-driven setting.  相似文献   

14.
A review of biofouling and its control in membrane separation bioreactors.   总被引:5,自引:0,他引:5  
Membrane separation technology is increasingly becoming an important innovation in biological wastewater treatment. Biofouling of the membrane is a major factor affecting the efficient and economic operation of membrane separation bioreactors (MBRs). This review summarizes the state-of-the-art progress in understanding the mechanisms and factors affecting membrane biofouling and the strategies for biofouling control. Biofouling mechanisms include the adsorption of soluble and suspended extracellular polymers on membrane surfaces and in membrane pores, the clogging of membrane pore structure by fine colloidal particles and cell debris, and the adhesion and deposition of sludge cake on membrane surfaces. Design and operating conditions of membrane modules and materials, hydrodynamic conditions in MBRs, process and environmental conditions of activated sludge systems, and the physicochemical properties of the wastewater are the dominant factors determining membrane biofouling. Current strategies to control biofouling include periodic relaxation, backwashing, chemical cleaning, and possible manipulation of hydrodynamic conditions and sludge properties. Achieving full integration of MBRs in wastewater treatment technology requires further research and development. Fundamental information on the bacteria, colloid, and membrane interaction, developed through multimethod and multiscale approaches, is particularly needed.  相似文献   

15.
We investigated PCDDs and related compounds in the blood of young Japanese women, approximately 20 years of age, who had not yet had children, and discussed how the TEQ level of PCDDs and related compounds in their blood may affect the next generation. Means of total TEQ levels were 0.063 pg/g for whole blood basis and 21 pg/g for lipid basis. TEQ of PCDDs, PCDFs and coplanar PCBs accounted for about 43, 34 and 23% of the total TEQ in the whole blood basis, respectively. In the lipid basis, their values were about 44, 34 and 22%, respectively. Previously, we investigated PCDDs and related compounds levels in mother's breast milk, lymphocyte subpopulation and thyroid function of their children, and found negative correlations between the TEQ level of PCDDs and related compounds and CD4+/CD8+, and/or the TEQ level of PCDDs and related compounds and the T4 level in 36 mothers and children. Of these cases, the average age was approximately 28 years. PCDDs and related compounds may be related to immunopathy, such as atopic dermatitis. The effects of PCDDs and related compounds on babies of young Japanese women are important and must be further evaluated.  相似文献   

16.
Cao X  Chen Y  Wang X  Deng X 《Chemosphere》2001,44(4):655-661
Equilibrium release experiments were conducted under three different pH values of 3.5, 5.5 and 7.5 as well as three redox potentials of 400, 0 and -100 Mv to investigate the influence of redox potential and pH value on the La, Ce, Gd and Y release of from the simulated-REEs-accumulation (SRA) soil. Oxygen and nitrogen were allowed to flow into soil suspension to adjust redox potential to a preset value, and 1 mol/l HCl or 1 mol/l NaOH solutions were added into the soil suspension to keep pH at a preset value. Results indicated that La, Ce, Gd and Y release increased gradually with the decrease of pH value or Eh, and the influence of redox potential on Ce was more remarkable than on La, Gd and Y. At the same time. It was observed that La, Ce, Gd and Y releases were positively correlated with the release of Fe and Mn, indicating that La, Ce, Gd and Y releases might originate from dissolution of Fe-Mn oxyhydroxides under reduction and low pH conditions. Moreover, it was found that alteration of pH value and redox potential might affect the change of La, Ce, Gd and Y species in the soil. The contents of La, Ce, Gd and Y in exchangeable fraction and Fe-Mn oxide fraction in the solid phase from soil suspension separation decreased with the decline of pH value and redox potential. Multiple stepwise regression analysis showed that exchangeable fraction and Fe-Mn oxide fraction predominately contributed to the La, Ce, Gd and Y release. Low pH value and redox potential were more favorable to La, Ce, Gd and Y releases following the change of their species. The La, Ce, Gd and Y contents in exchangeable fraction and Fe-Mn oxide fraction are the main contributors to their release.  相似文献   

17.
The Fresno Supersite intends to 1) evaluate non-routine monitoring methods, establishing their comparability with existing methods and their applicability to air quality planning, exposure assessment, and health effects studies; 2) provide a better understanding of aerosol characteristics, behavior, and sources to assist regulatory agencies in developing standards and strategies that protect public health; and 3) support studies that evaluate relationships between aerosol properties, co-factors, and observed health end-points. Supersite observables include in-situ, continuous, short-duration measurements of 1) PM2.5, PM10, and coarse (PM10 minus PM2.5) mass; 2) PM2.5 SO4(-2), NO3-, carbon, light absorption, and light extinction; 3) numbers of particles in discrete size bins ranging from 0.01 to approximately 10 microns; 4) criteria pollutant gases (O3, CO, NOx); 5) reactive gases (NO2, NOy, HNO3, peroxyacetyl nitrate [PAN], NH3); and 6) single particle characterization by time-of-flight mass spectrometry. Field sampling and laboratory analysis are applied for gaseous and particulate organic compounds (light hydrocarbons, heavy hydrocarbons, carbonyls, polycyclic aromatic hydrocarbons [PAH], and other semi-volatiles), and PM2.5 mass, elements, ions, and carbon. Observables common to other Supersites are 1) daily PM2.5 24-hr average mass with Federal Reference Method (FRM) samplers; 2) continuous hourly and 5-min average PM2.5 and PM10 mass with beta attenuation monitors (BAM) and tapered element oscillating microbalances (TEOM); 3) PM2.5 chemical speciation with a U.S. Environmental Protection Agency (EPA) speciation monitor and protocol; 4) coarse particle mass by dichotomous sampler and difference between PM10 and PM2.5 BAM and TEOM measurements; 5) coarse particle chemical composition; and 6) high sensitivity and time resolution scalar and vector wind speed, wind direction, temperature, relative humidity, barometric pressure, and solar radiation. The Fresno Supersite is coordinated with health and toxicological studies that will use these data in establishing relationships with asthma, other respiratory disease, and cardiovascular changes in human and animal subjects.  相似文献   

18.
Chiral herbicides may have enantioselective effects on plants. In this study, we assessed and compared the enantioselectivity of the chiral herbicides rac-metolachlor and S-metolachlor to maize seedlings. The superoxide dismutase activity (SOD) activity of roots and stem leaves treated by rac-metolachlor was 1.38 and 1.99 times that of roots and stem leaves treated by S-metolachlor. The peroxidase activity (POD) activity of roots and stem leaves was 1.48 and 2.79 times that of roots and stem leaves treated by S-metolachlor, respectively, while the catalase activity (CAT) activity was 4.77 and 8.37 times greater, respectively. The Hill reaction activity of leaves treated by rac-metolachlor were 1.45, 1.33, and 1.14 times those treated by S-metolachlor with treatments of 18.6, 37.2, and 74.4 μM. The differences observed between treatments of rac- and S-metolachlor were significant. Significant differences in maize seedling morphology were also observed between rac- and S-metolachlor treatments. The degradation rate of S-metolachlor in roots was greater than that of rac-metolachlor. The half-lives of rac- and S-metolachlor were 80.6 and 60.3 h at 18.6 μM; 119.5 and 90 h at 37.2 μM; and 169 and 164.8 h at 74.4 μM, respectively. Using the liquid chromatography-mass spectrometry method, hydroxymetolachlor, deschlorometolachlor and deschlorometolachlor propanol were considered to be possible metabolites. We determined the enantioselective toxicity of rac- and S-metolachlor to maize and speculated on the proposed metabolic pathway of metolachlor in maize roots. These results will help to develop an understanding of the proper application of rac- and S-metolachlor in crops, and give some information for environmental safety evaluation of rac- and S-metolachlor.  相似文献   

19.
The use of mechanical monitors and passive samplers has made it possible to assess concentrations of ozone over wide areas and to develop air quality standards, like AOT40 and SUM60. Monitored ozone data and AOT40 and SUM60 are also used to predict ozone injury on local and regional scales. The data and the standards do not include or account for environmental and biological variables that affect ozone uptake and plant injury. Ground proofing via vegetation surveys must be done to verify and validate plant injury predictions. If this is not done, then the standards have no biological significance and are only exercises in air quality assessment.  相似文献   

20.
We studied the effects of elevated heavy metal uptake on the sperm quality and the antioxidant mechanisms of sperm and testis of red deer from a Pb mining area in Spain. Testis, liver and bone of red deer from mining (n = 21) and control (n = 20) areas were obtained from hunters and analyzed for Pb, Zn, Cu, Cd, As and Se. Testes were weighed and measured. Motility, acrosome integrity and viability and functionality of membrane were evaluated in epididymal spermatozoa. Lipid peroxidation, total glutathione, glutathione peroxidase (GPX) and superoxide dismutase (SOD) were studied in testis and spermatozoa. Deer from mined areas showed less Cu in testis, a higher testis mass and size and reduced spermatozoa membrane viability and acrosome integrity. Effects on sperm quality were associated to decreased Cu and increased Se in testis, and to decreases in the activity of SOD and GPX in testis and spermatozoa.  相似文献   

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