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1.
Road traffic emits a cocktail of pollutants that can influence the vegetation and plant diversity in neighboring areas. However, the recovery potential of bryophytes after traffic abandonment is still little explored. In addition, the effects of the main pollutants of road verges, such as metals and salinity, on moss flora need to be investigated. In our study, we compared the moss richness and diversity in two closely related veteran tree allees of high conservation importance. The allees in Gry?ów and Lubrza, Poland, were chosen because of their similarity in age, geographical location, type of surrounding areas, and tree species. The only difference was that the trees in Gry?ów had not been exposed to direct road pollution for almost 30 years. The moss richness and diversity differed significantly between the sites. Altogether, 20 moss species were recorded on 229 trees, 17 species in Gry?ów (abandoned road), and 13 in Lubrza (busy road). We found considerable differences between moss cover on the road-facing and opposite sides of tree trunks. In Lubrza, mosses on the road-facing side were very scarce. The moss cover in Gry?ów was highly balanced between trunk sides as well as among trunk heights. Typical epiphytic species such as Bryum moravicum, Dicranoweisia cirrata, Leskea polycarpa, and Orthodicranum tauricum preferred the Gry?ów tree stands, where they were present in numbers almost twice as high as that at Lubrza. The study shows that constructing a bypass road could be an effective conservation measure for veteran tree protection with their epiphytic moss flora.  相似文献   

2.
A passive sampling device, developed for personal monitoring of airborne dust levels in industry, has been tested as a site sampler in the urban environment. The device weighs approximately 15g and the essential sampling element is a small disc of electret material (polymer carrying a permanent electric charge). During use it captures particles by electrical attraction, at a rate that depends upon their electrical mobility, but which is independent of the rate at which air flows past the sampler. It collects measurable quantities of particulate, though the sample size tends to be small and correlation with results from conventional samples has not yet been established. Samplers have been exposed to urban particulate for periods of up to seven days, without the electret suffering unacceptable loss of electric charge. It has been shown to be potentially useful for long-term monitoring, a situation in which dispensing with a power source is particularly useful. Being small, the passive sampler is easy to hide or camouflage. It has potential for multiple simultaneous site sampling and for monitoring personal environmental exposure.  相似文献   

3.
The effects of age on cadmium concentrations was investigated in Cory's shearwater, Calonectris diomedea, Lesser black-backed gull, Larus fuscus, and great skuas, Catharacta skua. There was no evidence for the continued accumulation of cadmium with increasing adult age. Adult shearwaters did have higher concentrations of cadmium compared to young fledglings, but there was no significant difference between cadmium concentrations in adult and sub-adult gulls. In addition, the sample of great skuas were of known age (3–22 yrs old) and showed no evidence of increasing cadmium concentrations with adult age in liver or kidney. However, it is possible that age accumulation of cadmium in great skuas was masked by individual dietary preferences overriding the effects of increasing age. It is often assumed that cadmium concentrations continue to accumulate with increasing adult age, but seabirds may have evolved some as yet unknown mechanism for excretion or more rapid turnover of cadmium than previously thought. The implications of this for the use of seabirds as biomonitors is discussed.  相似文献   

4.
The main problem of traditional methods of environmental impact assessment (EIA) is that in most of the existing algorithms and methods, such as Leopold, Folchi and RIAM, the main attention is to the destructive effects of the proposed plan, and the advantages of the industrial project are less noticeable. This has led to a permanent challenge between environmental organizations and industrial stakeholders. Data envelopment analysis (DEA) is a new approach of assessing the industrial units. Besides, it considers the positive economic and social impacts of the project and provides a comprehensive assessment of the industrial unit. With this approach, the environmental impacts of an industrial unit have been considered as “inputs” and its positive economic and social impacts considered as the “outputs” of the DEA models. Therefore, the problem of impact assessment changes into a DEA model. In the present study, the Alborz Sharghi Coal washing plant in northern Iran has been considered as a case study for implementing the DEA-EIA approach, and 19 plant activities and 11 environmental components have been used to evaluate the environmental effects of the plant. To solve the EIA problem, two commonly used DEA approaches, called CRS (constant returns to scale) and VRS (variable returns to scale), have been used. The DEA results identified the critical environmental components of the plant that should be considered seriously. Also, drawing the “potential improvement” diagram in the DEA method is an effective tool for determining the high risk activities of the factory and applying them in development plans. Besides, using the VRS model with maximize-output approach showed that some of the plant activities had the most differences with optimal mode and these components should be considered in future development plans. Finally, it can be concluded that, assessing the environmental impacts of the mineral industries with VRS maximize-output approach, is closer to the concept of sustainable development and cost-benefit analysis.  相似文献   

5.
The Pithampur Industrial sectors I, II, and III, located approximately, 45 km from Indore in Central India have emerged as one of the largest industrial clusters in the region. Various types of industries ranging from automobiles to chemicals and pharmaceuticals have been set up in the region since 1990. Most of the industries have effluent treatment plants (ETP) for treating wastewater before its disposal on land and/or in water body. The present study is an attempt to assess the groundwater quality in the watersheds surrounding these industrial sectors to develop the baseline groundwater quality in order to enable the policy makers to facilitate decisions on the development of industries in this region. The industries are located in two sub-watersheds, namely, Gambhir river sub-watershed and Chambal river sub-watershed. Geologically, the study area is located in the Deccan traps of Cretaceous to Paleocene age. The different basaltic flow units underlie clayey soils varying in thickness from 2–3 m. The aquifer is mostly of unconfined nature. Samples have been collected from a network of observation wells set up in the watersheds. The water quality analysis of the groundwater samples has been carried out six times during three hydrological cycles of 2004, 2005, and 2006. The results indicate that a few observation wells in the vicinity of the industrial clusters have very high TDS concentration and exceed the Bureau of Indian Standards (BIS) guideline for TDS concentration. The contamination of groundwater has been more severe in the Gambhir watershed as compared to the Chambal watershed. The presence of the impermeable clay layers has resulted in a slow migration of contaminants from the sources. The findings reveal that there is no significant groundwater contamination in the Pithampur industrial sectors except in the vicinity of the industrial clusters, which indicates that there is good environmental space available for the expansion of industrial units in the Pithampur industrial hub.  相似文献   

6.
Delhi is one of the many megacities struggling with punishing levels of pollution from industrial, residential, and transportation sources. Over the years, pollution abatement in Delhi has become an important constituent of state policies. In the past one decade a lot of policies and regulations have been implemented which have had a noticeable effect on pollution levels. In this context, air quality models provide a powerful tool to study the impact of development plans on the expected air pollution levels and thus aid the regulating and planning authorities in decision-making process. In air quality modeling, emissions in the modeling domain at regular interval are one of the most important inputs. From the annual emission data of over a decade (1990–2000), emission inventory is prepared for the megacity Delhi. Four criteria pollutants namely, CO, SO2, PM, and NO x are considered and a gridded emission inventory over Delhi has been prepared taking into account land use pattern, population density, traffic density, industrial areas, etc. A top down approach is used for this purpose. Emission isopleths are drawn and annual emission patterns are discussed mainly for the years 1990, 1996 and 2000. Primary and secondary areas of emission hotspots are identified and emission variations discussed during the study period. Validation of estimated values is desired from the available data. There is a direct relationship of pollution levels and emission strength in a given area. Hence, an attempt has been made to validate the emission inventory for all criteria pollutants by analyzing emissions in various sampling zones with the ambient pollution levels. For validation purpose, the geographical region encompassing the study area (Delhi) has been divided into seven emission zones as per the air quality monitoring stations using Voronoi polygon concept. Dispersion modeling is also used for continuous elevated sources to have the contributing emissions at the ground level to facilitate validation. A good correlation between emission estimates and concentration has been found. Correlation coefficient of 0.82, 0.77, 0.58 and 0.68 for CO, SO2, PM and NO x respectively shows a reasonably satisfactory performance of the present estimates.  相似文献   

7.
A method for estimating the impact of industrial emissions is suggested and applied to the Guadalajara City Metropolitan Area (GCMA). The method is based on solutions to the pollution transport model and its adjoint. Two equivalent direct and adjoint mean pollution concentration estimates are considered for ecologically important zones of the GCMA. The dependence of these estimates on the number, positions and emission rates of industrial plants, as well as on the wind and initial pollution distribution in the GCMA is qualitatively and quantitatively examined. It is shown that the adjoint model solutions serve as the influence functions providing valuable information on the role of each of the industrial plants in polluting different zones within the GCMA. These solutions have been calculated with a balanced and absolutely stable second-order finite-difference scheme based on the splitting method. A method for an optimal allocation of a new industrial plant is considered.  相似文献   

8.
The Respicon has been introduced as a sampler for health related measurements of airborne contaminants at workplaces. The instrument is aimed at simultaneous collection of three health related aerosol fractions: (a) the coarser inhalable fraction, defining the aerosol fraction that may enter the nose and mouth during breathing; (b) the intermediate thoracic fraction, defining the fraction that may penetrate beyond the larynx and so reach the lung; and (c) the finer respirable fraction, defining the fraction that may penetrate to gas exchange region of the lung. The instrument has a number of features attractive to occupational hygienists: in addition to providing the three aerosol fractions simultaneously, it is light and compact enough to be used as a personal sampler. yet can be a tripod mounted for area sampling, it can provide samples not only for gravimetric analysis but also microscopic and chemical analyses; and it is also available in a photometric direct-reading version. The instrument has previously been evaluated as an area sampler and, in this mode of operation, has shown reasonable accuracy in collecting respirable, thoracic and inhalable particles, the latter up to particle diameters of ca. 80 microm. Except for some scattered unpublished data there exist no systematic investigations in the Respicon's performance when used as a personal sampler in the industrial environment. In this paper, we will report on a study of side by side comparison of the Respicon with the IOM inhalable sampler, regarded as a reference instrument for the inhalable fraction. The main study was performed at six different workplaces in a nickel refinery. Statistical analysis of the gravimetrically-determined concentration data reveals consistently lower aerosol exposure values for the Respicon as compared to the IOM sampler. The data for the nickel workplaces are compared with findings from other studies. The results are interpreted in the light of the overall results and the possibility of introducing a correction factor is discussed.  相似文献   

9.
Unplanned industrialization and urbanization are causing health hazard mainly in developing countries. It is essential to assess the magnitude of future hazard in an industrial town. The geographical information system is a special type of tool evolved to analyse geographic data for efficient planning. In India large-scale industrialization started after independence. New industrial towns have been established and Durgapur in West Bengal is one of them. In this study an indigenously developed GIS package GRAM has been used to assess air quality in Durgapur town. Using GIS, interpolated maps have been prepared showing the distribution of five pollutants, i.e. carbon monoxide, total oxidant, nitrogen-oxide, sulfur-dioxide and suspended particulate matter. The maps have been used to find the pollutant standard index of the area. The final map shows that the PSI index is high and ranges between the unhealthy to very unhealthy category. This map has been combined with a present landuse pattern. There are three pockets of extremely poor air quality zones which generally match with industrial units. Areas around these units are the potential zones of health hazard. Large numbers of patients admitted in hospitals here suffer from obstructive diseases. Most of them belong to the working age group. This may indicate that the main work force is exposed to the health hazard due to industrial pollution.  相似文献   

10.
The epiphytic moss Polytrichum juniperinum and the tree bark of Azardirachta indica were used to determine the atmospheric Cd, Cu, Pb, Mn, Fe, Ni and Zn levels in the North-East region of Nigeria. A good correlation exists between levels in the moss and the tree barks. The Pb, Zn and Fe levels in both sample types were higher than other metals in most sites. There was no significant difference in the levels of Cd, Cu, Ni and Mn recorded for inhabited and forest sites. The area derives its atmospheric metal contamination from vehicular, urban, industrial and agricultural sources.  相似文献   

11.
Urban wastewater treatment plant efficiency, as well as biosolid quality, depends on urban wastewater quality, which can be affected by non domestic discharges (industrial, commercial etc.). The characterization of wastewater quality and non domestic discharge is complex, expensive and time consuming. However, these discharges must be controlled and reduced if possible. The development of a simple and fast methodology, namely based on alternative methods such as UV spectrophotometry, has been carried out and applied to different areas of a medium sized town of Southern Québec (Canada). Several autosamplers and on line/on site measurements have been used in critical control points of the network areas, for a dry weather campaign in four areas (industrial, commercial, hospital and university). The flow rate study, completed by the exploitation of conductivity measurements and the qualitative examination of UV spectra allows the discrimination of non domestic loads and their variability study from one point to another. The identification of critical discharges and organic shock loads has been possible with low investment, and mitigation actions have been proposed.  相似文献   

12.
Natural ecosystems are renewable resources with special environmental, social, and economical attributes and characteristics. The increasing need of human beings for a better environment results in the use of new technologies that offer many advantages in detecting changes in the ecosystems. Remote sensing tools, technology, and the spatial analysis of the Geographic Information System were used in determining any changes in this study which attempts to classify land cover over a 10-year period. The study area is in Thessaly, central Greece, and has been classified as a Special Protection Area, because of its important wild fauna. The results have shown that current technologies can be used for modeling environmental parameters which improve our knowledge of the attributes, characteristics, situation, trends, and changes of natural ecosystems. The changes over time that have been observed result from the development of the vegetation or to anthropogenic and socioeconomic reasons. Rational range management will be a very comprehensive tool for farmers. This action will have a positive impact on flora in the rangelands. The core strategy is to combine forest, pasture, and livestock so that each component produces usable products.  相似文献   

13.
The main scientific problems of the programme on investigating the World Ocean's role in short-range climatic variations are discussed. It has been shown that data obtained within the framework of the SECTIONS, TOGA and other programmes should serve as a baseline for ocean physical characteristics monitoring. Some preliminary numerical experiments have been carried out.  相似文献   

14.
Dynamics of epiphytic lichen distribution and diversity in the town of Skawina, one of the major industrial centres of southern Poland, over the last 30 years, was documented in relation to air quality changes. Fieldwork was conducted in 2006-2007. A total of 34 species were recorded at 202 sites, which is similar to the historical data, however, significant qualitative changes occurred. Nitrogen- and dust-tolerant species have expanded and dominate, while some acidophytes, such as Lecanora conizaeoides, are in decline. Lichens have recolonised the former 'lichen desert' in the town centre. Species richness at study sites has increased; and an improvement in the health of lichen thalli was noted. These trends reflect air quality improvement, mainly SO(2) decline in the last few decades and transport-related compounds, mainly NO(x) and dust that have became the main pollutants. Host tree species and diameter diversity also contribute significantly to lichen species diversity in the study area. The recolonisation process seems far from complete and further changes in the lichen distribution and diversity in the study area are expected.  相似文献   

15.
Recognizing the array of effects that invasive alien species have, documenting their status from biodiversity rich regions has been much emphasized. Lack of such studies is a major limitation that hampers proper management of alien species. The present paper, therefore, documents the alien flora of the Indian Himalayan state of Himachal Pradesh (HP) based on data obtained from literature and herbarium records. The alien flora of HP comprises of 497 species belonging to 85 families. Majority of them belong to family Asteraceae (59 species), followed by Poaceae (47 species) and Fabaceae (43 species). Amongst the genera, Ipomoea (9 species), Eucalyptus and Euphorbia (7 species each) are the most predominant. Herbs constitute the majority (i.e., 73 %) of alien species and a large percentage of them (i.e., 22.94 %) have South America as their native region. Further, of the total alien species, 248 are intentional introductions and majority (31 % species) have been introduced for ornamental purposes. It was revealed that 34 % species have naturalized while 29 % species have become invasive. Today, in addition to human-disturbed landscapes, alien species have also been reported from dense forests. Himalaya being a biodiversity hotspot and HP being a bio-rich Himalayan state, it is hoped that this inventory and assessment of alien flora will help in designing informed management and monitoring strategies against problematic plant invasions in the state.  相似文献   

16.
The Air Quality Index (AQI) is an index for reporting daily air quality. A study on the annual and seasonal variations of Air Quality Index over a period of 9 years (1996-2004) based on daily averaged concentration data of criteria air pollutants has been conducted for Delhi. An attempt has been made to quantify the changes in the AQI on annual and seasonal (winter, summer, monsoon and post monsoon) basis for 9 years. Measurements for the seven monitoring sites (Nizamuddin, Ashok Vihar, Shahzada Baug, Shahadara, Janakpuri, Sirifort and ITO) in Delhi were analysed and trends were also compared amongst these sites. Maximum Operator Function method was used to compute the Air Quality Index of the above areas and percentage variations in different severity class is discussed which provides in depth analysis of the trends. The best air quality was depicted by Shahzada Baug followed by Shahdara, both of these were classified as industrial areas indicating that policy measures relating to the industries in the city during past years have helped in improving the air quality. The air quality in other areas have improved slightly in the span of nine years but still remains critical indicating continued rigorous efforts in this direction. Increased traffic density seems to have resulted into the worst air quality at ITO in the city amongst all the monitoring stations. There is a shift for the worst AQI in the city from winter to summer season in a time span of these nine years. Change of season for worst AQI from Winter to Summer may also be likely due to increased photochemical reactions playing major role with change in the nature of emissions imposed due to different control measures such as CNG implementation, significant shift to LPG in domestic sector etc. calling for a detailed study, those which started after the year 2000. After the year 2000, there is a significant increase in the Nitrogen-dioxide (NO(2)) concentration at all stations. ITO which has shown continuous exponential increase in pollution levels has first time showed a declining AQI trend in the year 2004 and one of the contributing factors could have been the Delhi metro (initiated in 2002) passing through congested neighbouring areas causing traffic decongestion here. In general, the areas which are farthest from metro route viz., Siri-fort, Nizamuddin, Janakpuri etc. did not record declining AQI in 2003 onwards as happened with stations closer to Metro route such as Ashok Vihar and ITO. An attempt has been made to quantify the reasons that lead to the changes in the values of the AQI.  相似文献   

17.
Various studies have been conducted in the past on the fresh waters related to the various aspects of limnology, physico-chemistry, primary productivity, plankton etc. in relation to environmental conditions and ecology, flora and fauna of River Ganga. In the present investigation some recent approach have been made to study the various parts of fishes like gill structures, scales for age determination, length and weight of fish for growth assessments etc. The SEM study of scales in relation to pollution and environmental conditions is a recent approach. At this stage, in the present study the scales of two most common fishes found in the study stretch were involved to create a base line.  相似文献   

18.
Desertification involves the loss of soil productive potential, but a means of assessing and monitoring the progress of desertification on the soil has been elusive. Soil is so varied and complex that methods of assessing condition are too slow, tedious, and expensive for routine use. Moreover, differences in soil type can be confused with soil condition. This paper presents a structured method of assessing soil condition. This method is based on recognizing and classifying soil surface features and examining soil properties that reflect the status of the processes of erosion, infiltration, and nutrient cycling. Published in the form of a user manual, the method has the following three stages: (1) defining the geomorphic setting of the site, (2) recognizing patch/interpatch associations and the mode of erosion at the landscape scale, and (3) assessing soil surface condition ratings in quadrats sited within the landscape pattern patches. Stage 3 is achieved by observing each of 11 features in the field and classifying their status according to detailed fieldnotes and photographs. The method applies to a wide range of soil types and biogeographical regimes and has proven to be repeatable among observers and quickly transferred to new observers.  相似文献   

19.
Studies on quantitative soil contamination due to heavy metals were carried out in Katedan Industrial Development Area (KIDA), south of Hyderabad, Andhra Pradesh, India under the Indo-Norwegian Institutional Cooperation Programme. The study area falls under a semi-arid type of climate and consists of granites and pegmatite of igneous origin belonging to the Archaean age. There are about 300 industries dealing with dyeing, edible oil production, battery manufacturing, metal plating, chemicals, etc. Most of the industries discharge their untreated effluents either on open land or into ditches. Solid waste from industries is randomly dumped along roads and open grounds. Soil samples were collected throughout the industrial area and from downstream residential areas and were analysed by X-ray Fluorescence Spectrometer for fourteen trace metals and ten major oxides. The analytical data shows very high concentrations of lead, chromium, nickel, zinc, arsenic and cadmium through out the industrial area. The random dumping of hazardous waste in the industrial area could be the main cause of the soil contamination spreading by rainwater and wind. In the residential areas the local dumping is expected to be the main source as it is difficult to foresee that rain and wind can transport the contaminants from the industrial area. If emission to air by the smokestacks is significant, this may contribute to considerable spreading of contaminants like As, Cd and Pb throughout the area. A comparison of the results with the Canadian Soil Quality Guidelines (SQGL) show that most of the industrial area is heavily contaminated by As, Pb and Zn and local areas by Cr, Cu and Ni. The residential area is also contaminated by As and some small areas by Cr, Cu, Pb and Zn. The Cd contamination is detected over large area but it is not exceeding the SQGL value. Natural background values of As and Cr exceed the SQGL values and contribute significantly to the contamination in the residential area. However, the availability is considerably less than anthropogenic contaminants and must therefore be assessed differently. The pre- and post-monsoon sampling over two hydrological cycles in 2002 and 2003 indicate that the As, Cd and Pb contaminants are more mobile and may expect to reach the groundwater. The other contaminants seem to be much more stable. The contamination is especially serious in the industrial area as it is housing a large permanent residing population. The study not only aims at determining the natural background levels of trace elements as a guide for future pollution monitoring but also focuses on the pollution vulnerability of the watershed. A plan of action for remediation is recommended.  相似文献   

20.
Genetically modified (GM) crops are now approved for commercial use in several world areas. In terms of commercial acreage, the majority of these products possess either herbicide tolerance or insect protection traits. Prior to commercialization, each product underwent a country specific review of environmental safety data by independent regulatory authorities. Registration was granted after review of the data allowed authorities to conclude that the risks were minimal or manageable when balanced with the benefits. As a condition of registration, insect resistance management (IRM) has been imposed for insect protected products in most countries. Other world areas have reviewed similar data packages and have not yet been able to grant registration for commercial release. Post-registration environmental monitoring of GM crops is viewed in some world areas as a means of enabling approvals by addressing uncertainty that exists with this technology. Questions such as, who should monitor and who should pay for it, how should monitoring be conducted, what information is necessary to collect and how long should a given product be monitored are yet to be answered. Monitoring methods could be general (surveys and questionnaires) or specific (scientific studies to address specific questions). Independent research currently underway in countries where GM crops are commercial involves monitoring the benefits as well as the risks of these products. Experience with other products has shown that monitoring of GM crops will be of value only if the questions are clearly defined, the methods are appropriate and the end points (data collected) are interpretable.  相似文献   

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