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1.
The effects of air pollution on plants downwind of a fertilizer factory at Udaipur, India, were studied using three woody perennials. Seedlings of these species including a shrub (Carissa carandas L.), a leguminous avenue tree (Cassia fistula L.) and a fruit tree (Psidium guajava L.) were grown in earthen pots at different study sites receiving varying levels of air pollution input. Changes in plant growth, morphological characteristics, photosynthetic pigment, ascorbic acid, N and S contents and in dry matter allocation were considered in relation to the status of ambient air quality. Observations with these parameters have indicated that the ambient air around the factory contained pollutants at phytotoxic levels. Plant height, basal diameter, conopy area, leaf area and chlorophyll, ascorbic acid and foliar-N concentrations decreased with increasing pollution load. However, foliar-S increased slightly at polluted sites. Air pollution load around the factory have also altered the biomass allocation. Root:shoot ratios increased in C. fistula and P. guajava at polluted sites. In contrast, for C. carandas the above ground parts, where foliage assumed predominance showed precedence over the root growth. This species responded characteristically to air pollution stress by allocating more of its photosynthate towards leaf production and shoot growth.  相似文献   

2.
The air pollution due to anthropogenic activities seriously affected human life, vegetation, and heritage as well. The vegetation cover in and around the city mitigates the air pollution by acting as a sink for pollution. An attempt was made to evaluate biochemical changes occurred in four selected plant species, namely Azadirachta indica, Mangifera indica, Delonix regia, and Cassia fistula of residential, commercial, and industrial areas of Nagpur city in India. It was observed that the correlated values of air pollutants and plant leaves characteristics alter foliar biochemical features (i.e., chlorophyll and ascorbic acid content, pH and relative water content) of plants due to air pollution. The changes in air pollution tolerance index of plants was also estimated which revealed that these plants can be used as a biomarker of air pollution.  相似文献   

3.
This study was conducted in the urban environment of Varanasi, India, to evaluate the plant responses to urban air pollution. Twenty sites were selected in four different zones of the city. At each site, seven woody perennials of same age classes were selected. Out of the four zones (I, II, III and IV), zone IV was used as a reference (control) zone as it received the minimum pollution input. Plant species growing in polluted and control areas were compared with respect to foliar dust load, per cent leaf area injury, leaf area, specific leaf weight and chlorophyll, ascorbic acid, SO 4 2– S and total N concentration in the leaves. Results indicated that the air pollution level in Varanasi causes leaf damage, reduces leaf area, specific leaf weight and chlorophyll, ascorbic acid and total N concentrations in the leaves. Sulphur concentration in leaves increased with increasing level of SO2 in the ambient air. The magnitude of such changes was maximum at the zone receiving maximum pollution load. Carissa carandas was found to be the most sensitive species and Bougainvillea spectabilis, the least. The study shows that the urban air pollution level in Varanasi is detrimental for the growth of plants involved in this study.  相似文献   

4.
Air pollution has been identified as a serious problem throughout the world which causes tremendous loss to the crops by affecting plant growth and yield. Earlier, air pollution was restricted to urban and industrial regions. Over the last few decades, however, it has become evident that pollutants can be transported over long distances and hence their impact may be felt widely over rural areas. The present study was conducted to evaluate the impact of urban air pollution on suburban agriculture with respect to the changes in photosynthetic rate, stomatal conductance, water-use efficiency, plant height, numbers of tillers, leaves, ears and seeds, chlorophyll, carotenoid, protein, phenol, ascorbic acid, nitrogen and sulphate-sulphur contents and seed weight of pot-grown wheat plants (Triticum aestivum var. HUW 468) kept at different sites around Varanasi city receiving varying levels of pollution load. Mean concentrations of were monitored. The study clearly showed that plants are negatively affected by the ambient levels of air pollutants. Reduction in various parameters directly corresponded with the air pollution levels at different sites.  相似文献   

5.
Dust is considered as one of the most widespread air pollutants. The objective of the study was to analyse the effect of dust load (DL) on the leaf attributes of the four tree species planted along the roadside at a low pollution Banaras Hindu University (BHU) campus and a highly polluted industrial area (Chunar, Mirzapur) of India. The studied leaf attributes were: leaf area, specific leaf area (SLA), relative water content (RWC), leaf nitrogen content (LNC), leaf phosphorus content (LPC), chlorophyll content (Chl), maximum stomatal conductance (Gsmax), maximum photosynthetic rate (A max) and intrinsic water-use efficiency (WUEi). Results showed significant effect of sites and species for DL and the leaf attributes. Average DL across the four tree species was greater at Chunar, whereas, the average values of leaf attributes were greater at the BHU campus. Maximum DL was observed for Tectona grandis at Chunar site and minimum for Syzygium cumini at BHU campus. Across the two sites, maximum value of SLA, Chl and Gsmax were exhibited by S. cumini, whereas, the greatest value of RWC, LNC, LPC, A max and WUEi were observed in Anthocephalus cadamba. A. cadamba and S. cumini exhibited 28 and 27 times more dust accumulation, respectively, at the most polluted Chunar site as compared to the BHU campus. They also exhibited less reduction in A max due to dust deposition as compared to the other two species. Therefore, both these species may be promoted for plantation along the roadside of the sites having greater dust deposition.  相似文献   

6.
A biomonitoring study was conducted to investigate the responses of plants exposed to power plant emission in a dry tropical environment. For this purpose, five sampling sites were selected in the prevailing wind direction (NE) at different distance to thermal power plant (TPP) within 8.0 km range and a reference site was selected in eastern direction at a distance of 22.0 km. The two most common tree species, Ficus benghalensis L. (Evergreen tree) and Dalbergia sisso Roxb. (deciduous tree) were selected as test plants. Ambient sulphur dioxide (SO(2)), nitrogen dioxide (NO(2)), suspended particulate matter (SPM), respirable suspended particulate matter (RSPM), dust-fall rate (DFR) and plant responses such as leaf pigments (chlorophyll a, chlorophyll b and carotenoids), ascorbic acid, sugar and sulphate-sulphur (SO4(2-)-S) contents were measured. Ambient SO(2), NO(2), SPM, RSPM and DFR showed significant spatial and temporal variation at different sites. Considerable reduction in pigment (chlorophyll a, chlorophyll b and carotenoids) and sugar contents were observed at sites receiving higher pollution load. Ascorbic acid exhibited significant positive correlation with pollution load. Accumulation of SO4(2-)-S in leaf tissue showed significant positive correlation with ambient SO(2) concentration at all the sites. At the same time, SO4(2-)-S showed significant negative correlation with pigment and sugar content. D. sisso Roxb. tree was found to be more sensitive as compared to F. benghalensis L. tree.  相似文献   

7.
淄博化工园区大气有机污染应急监测与管理对策   总被引:3,自引:0,他引:3  
针对工业聚集区内多种恶臭混杂的情况,以淄博化工园区为例,研究了大气有机污染突发事件中有机物的应急监测方法,并提出了治理对策。利用便携式气相色谱-质谱联用仪,对重点企业事先监测,掌握各企业特征污染物,作为应急监测查找污染源头的依据;现场分析受污染空气中的化合物组成及浓度,通过查询、比对各企业特征污染物,确认责任排污企业。提出了末端监测处罚治理与对重点污染企业推行清洁生产相结合,应急监测与有机污染物在线监测相结合,建立企业污染源特征组分数据库,加强企业无组织排放监测与监管等治理大气有机污染的建议。  相似文献   

8.
Loss of green cover, and increasing pollution is a prime global concern. The problem calls for screening of pollution-tolerant tree species that can be integrated into plantation drives. Recognizing this, the study analyzed bio-indicator responses and performance of commonly occurring plant species along a pollution gradient in western Himalaya. Based on distance from the road, three sites viz., highly polluted (HP), moderately polluted (MP), and least polluted (LP), were identified. From these sites, leaves of commonly occurring 26 tree species were collected and analyzed for dust accumulation, total chlorophyll, relative water content (RWC), ascorbic acid, and pH using standard protocols. Later, assessment of Air Pollution Tolerance Index (APTI) and Anticipated Performance Indices (API) was carried out. The results revealed variations in biochemical characteristics. The pH, RWC, and total chlorophyll increased with decreasing pollution while ascorbic acid increased with increasing pollution. Dust capturing potential of Ficus carica (1.191 mg/m2) and Toona ciliata (0.820 mg/m2) was relatively higher. Based on the results of APTI, Grevillea robusta was classified as tolerant. It scored significantly higher values (21.06, 21.19, and 19.61 in LP, MP, and HP sites, respectively). Quercus floribunda, G. robusta (68.75% each), Juglans regia (68.7%), and T. ciliata (62.50%) were good performers in HP sites. Acer caesium, Betula utilis, and Morus alba that had low API scores (43.75%) were predicted as poor performers. Thus, G. robusta, Q. floribunda, J. regia, T. ciliata, and F. carica were evaluated as best performers. They could be integrated into plantations drives for environmental management.  相似文献   

9.
The river Ravi, while passing through Lahore, the second largest city of Pakistan, gets highly polluted owning heavy loads of untreated municipal sewage and industrial effluents of diverse kinds. The fish, Catla catla sampled in two different seasons from three downstream polluted sites were compared with the samples of the same fish from an upstream, a less polluted site, for their physico-chemical parameters. The data were statistically analysed to study the effect of sites, seasons and their interaction on the physico-chemical parameters of waters and mineral uptake in fish muscles. Significant differences (P?<?0.001) among the sampling sites and seasons were observed. The river appeared to be polluted as indicated by the high values of total suspended solids (909 mg/l) and sulphate (964 mg/l) in comparison to the respective values of 150 and 600 mg/l being suggested as the safer values of drinking water of the National Environmental Quality Standards. Most trace and macro elements in fish muscles were increased with the increasing pollution loads from the upstream to the downstream sites of this river. The remarkable increases in the levels of all the investigated minerals in fish muscles from the polluted sites raise concerns about the long-term health of the river Ravi ecosystem and consequently the fish and its consumer’s health. The results contradict the opinion of the local population that the riverine fish are natural, more health-promoting and precious than the pond fish. Therefore, we strongly argue for the utilization of an effect-based monitoring approach to alleviate the detrimental effects of anthropogenic activities on fish and the fish consumers’ health.  相似文献   

10.
Patterns of epilithic diatom species distribution in relation to environmental variables from 12 sampling sites on the main stream and some of its tributaries in the Nilüfer Stream Basin were determined using multivariate statistical techniques. The stream basin has been heavily influenced by anthropogenic effects. The upper part of the basin that is distant from pollution sources mostly has a spring water quality, while the lower part where the stream flows through the urban area and receives domestic and industrial wastewater has a quite low quality. Ordination techniques using both diatom taxa and 21 environmental variables revealed non- to slightly polluted upper basin sites and highly polluted lower basin sites along the stream. The results showed that the stream catchment is polluted gradually from upstream to downstream and that most of the downstream sites have very low water quality especially in summer months. A total of 134 epilithic diatom taxa belonging to 50 genera were recorded for 12 sample sites. Partial CCA results indicated that water temperature (T), discharge (Q), and total phosphorus (TP) were the most important variables affecting the distribution of diatom species. Unpolluted or slightly polluted upper basin sites were dominated by Achnanthidium minutissimum, Cocconeis placentula var. euglypta, Gomphonema olivaceum, and Navicula tripunctata. Highly polluted lower basin sites were characterized by high levels of organic and inorganic matters and low dissolved oxygen (DO) values. Species widespread in the highly polluted lower basin sites such as Nitzschia umbonata, Nitzschia amphibia, Nitzschia capitellata, Nitzschia palea, Nitzschia paleacea, Luticola mutica, and Stephanodiscus niagarae were mostly related to pollution indicator variables such as ammonium nitrogen (NH4 +–N), sodium (Na+), total phosphorus (TP), and total organic matter (TOM).  相似文献   

11.
能源结构变化对兰州市大气质量的影响   总被引:2,自引:2,他引:0  
将2001—2010年的主要能源材料消耗、主要污染物变化及主要行业分布进行了相关性分析,结果表明:兰州市大气4种主要污染物中除烟尘呈下降趋势外,废气总量、SO2、NOx仍呈上升趋势;主要污染源为燃煤,主要污染行业为电力、蒸汽热水产供业;废气和SO2排放总量与燃煤和燃气呈强正相关,而NOx排放只与燃气呈强正相关。建议发挥兰州地域优势,加大以水电供应为主的能源结构调整,对改善当地空气质量有重要价值。  相似文献   

12.
Ambient air quality data, including atmospheric visibility, of Foshan city, a highly polluted city in the Pearl River Delta (PRD), and data obtained by the On-line Air Pollutant Exhaust Monitoring Network (OAPEMN), recently established by the National Emission Monitoring and Control Network for major industrial enterprises, were analyzed and are reported here for the first time, revealing the change in air pollution patterns and its impact on visibility degradation in the last decade. Reduced visibility of less than 8 km (after elimination of rainy and foggy periods) was found 22% of the time from 1998 to 2008, accompanied by elevated levels of pollutants, especially SO2 and PM10, in comparison with that of other developed cities. However, PM10 showed a steady decreasing trend (0.004 mg m???3 year???1) during 2001?C2008, in contrast to the noticeable increase in ambient NO2 concentrations from ~0.020 mg m???3 before 2005 to above 0.050 mg m???3 afterward. Multiple regression analysis revealed that the percentage of reduced visibility strongly correlated with PM10 concentration, suggesting that visibility degradation was directly proportional to the loading of particles. Moreover, the fairly significant correlation between reduced visibility and NO2 concentration also implied that the impact of primary emissions of NO2 and enhanced secondary pollutants, formed via photochemical processes in the atmosphere, could not be ignored. The decreased PM10 levels were obviously the predominant factor for the improvement in visibility (5.0% per 0.01 mg m???3) and were likely due to the implementation of stricter air pollution control measures for industrial exhaust, which also resulted in reduced SO2 pollution levels in the recent 2 years. In particular, the OAPEMN records showed an overall enhanced SO2 removal by 64% in major industrial sectors. The continuous increase in road traffic and lack of efficient NO x control strategies in the PRD region, however, caused an increase in ambient NO2 concentrations.  相似文献   

13.
Major environmental impacts of opencast mining are degradation of landscape and aesthetics of the area by creating huge overburden dumps and deep voids at the mining sites. These overburden dumps are characterised by high rock fragment contents, low moisture retention capacity, higher bulk density, low nutrients, lower pH and elevated metal concentrations. Overburden dumps are reclaimed by tree species for stabilising as well as pollution control and overall improvement of the visual aesthetics. A field study was carried out in the old reclaimed coal mine overburden dumps at KD Heslong project, Central Coalfields, India to study the physico-chemical changes in the reclaimed overburden dumps and determines the magnitude of trace elements accumulation in the planted tree species. Total, bioavailable and acid extractable trace metals concentration in minesoils of overburden dump and topsoil in the mining areas was compared with undisturbed soil. The study showed that tree plantation improves the moisture contents, bulk density, pH and overall nutrient contents of minesoils. The study revealed that lower pH in the minesoils increases the bioavailabity of metals but concentration were found within toxic limits. However, ratio between total and bioavailable metals was found lower in overburden dumps than topsoil due to low pH and lack of organic matter. Out of six tree species studied, Bambusa shows highest accumulation of Fe and Cr. Bioaccumulation coefficient for Cr and Zn was found 74 times in Bambusa and 83 times in Dalbergia sissoo. The results of the study underscore the need for close monitoring of trace elements in reclaimed overburden dumps. Tree species like Dalbergia sissoo, Eucalyptus, Cassia seamea, Acaccia mangium and Peltaphorum were found to be the best species for bioreclamation of overburden dumps.  相似文献   

14.
Considering the mounting evidences of the effects of air pollution on health, the present study was undertaken to assess the ambient air quality status in the fast growing urban centres of Haryana state, India. The samples were collected for total suspended particulate matter (TSPM), respirable suspended particulate matter (PM10), sulfur dioxide (SO2), and oxides of nitrogen (NO2) during different seasons from 8 districts of Haryana during January, 1999 to September, 2000. The four types of sampling sites with different anthropogenic activities i.e. residential, sensitive, commercial and industrial were identified in each city. The ambient air concentration of TSPM and PM10 observed was well above the prescribed standards at almost all the sites. The average ambient air concentrations of SO2 and NO2 were found below the permissible limits at all the centres. Comparatively higher concentration of SO2 was observed during winter seasons, which seems to be related with the enhanced combustion of fuel for space heating and relatively stable atmospheric conditions. Air Quality Index (AQI) prepared for these cities shows that residential, sensitive and commercial areas were moderately to severely polluted which is a cause of concern for the residents of these cities. The high levels of TSPM and SO2 especially in winter are of major health concern because of their synergistic action. The data from Hisar city reveals a significant increase in the total number of hospital visits/admissions of the patients with acute respiratory diseases during winter season when the level of air pollutants was high.  相似文献   

15.
Decrease in lichen diversity is an important biometric tool to assess the prevailing environmental condition in an area. An attempt has been made to explore the utility of lichen diversity in the monitoring of air pollution in the city of Pauri and Srinagar, Garhwal Himalayas, Uttaranchal. Eighty five lichen species were recorded from Pauri and Srinagar (Garhwal) in June 2005. It was observed that polluted sites had very low lichen diversity, mostly dominated by members of lichen family Physciaceae. Kiyonkaleshwar area is the site with maximum lichen diversity (46 lichen taxa) located in a more or less pollution-free area of Pauri city. Two-dimensional principal components analysis plot revealed significant positive contribution of natural (unaltered) sites towards lichen biodiversity, thus affirming the utility of lichen diversity in biomonitoring studies in a wide geographical area.  相似文献   

16.
Abstract Industrial development and consumption of petroleum products leads to increase air pollution levels especially in urban and industrial areas. Heavy metal components associated with air pollutants have far reaching effects with respect to economic and ecological importance of pollens. The pollens are male reproductive organs of the plant and travel through air from flower to flower for pollination purpose. During this period they are exposed to air pollutants. Present investigation thus pertains to study of effect of air pollutants on pollens especially biosorption and bioaccumulation of heavy metals. The pollens of three commonly occurring plants namely Cassia siamea, Cyperus rotundus, Kigelia pinnata have been studied from the NH-6 of Nagpur city, India. The pollens exposed to polluted air showed the presence of higher concentrations of Ca, Al and Fe as compared to unexposed pollens. Higher concentration of these metals was observed in Cyperus rotundus followed by Cassia siamea and Kigelia pinnata. These results indicate that pollens act as good indicator of air pollution giving results in short time of exposure of 5–10 h. Apart from this, it is also reported that some of these metals play crucial role in the metabolic activity in pollens for example Calcium is necessary for growth of pollen tube and other metabolic activities in pollens. The presence of these metals in pollens may also enhance the allergenicity of the pollens. Similarly accumulation of heavy metals may also deteriorate the quality of pollen for their economical use. The viability of pollen is also affected by these pollutants in sensitive species leading to impairment of their fertility.  相似文献   

17.
The first objective of this study was to provide data of arsenic (As) levels in Peninsular Malaysia based on soil samples and accumulation of As in Centella asiatica collected from 12 sampling sites in Peninsular Malaysia. The second objective was to assess the accumulation of As in transplanted C. asiatica between control and semi-polluted or polluted sites. Four sites were selected which were UPM (clean site), Balakong (semi-polluted site), Seri Kembangan (semi-polluted site) and Juru (polluted site). The As concentrations of plant and soil samples were determined by Instrumental Neutron Activation Analysis. The As levels ranged from 9.38 to 57.05 μg/g dw in soils, 0.21 to 4.33 μg/g dw in leaves, 0.18 to 1.83 μg/g dw in stems and 1.32–20.76 μg/g dw in roots. All sampling sites had As levels exceeding the CCME guideline (12 μg/g dw) except for Kelantan, P. Pauh, and Senawang with P. Klang having the highest As in soil (57.05 μg/g dw). In C. asiatica, As accumulation was highest in roots followed by leaves and stems. When the As level in soils were higher, the uptake of As in plants would also be increased. After the transplantation of plants to semi-polluted and polluted sites for 3 weeks, all concentration factors were greater than 50 % of the initial As level. The elimination factor was around 39 % when the plants were transplanted back to the clean sites for 3 weeks. The findings of the present study indicated that the leaves, stems and roots of C. asiatica are ideal biomonitors of As contamination. The present data results the most comprehensive data obtained on As levels in Malaysia.  相似文献   

18.
建立了大气污染物浓度与影响因子之间的BP神经网络,对城市中各监测点位的次日大气污染物浓度进行预测,采用GIS的插值分析进行污染物空间分布预测,其中BP神经网络的输入向量采用AGNES算法进行处理。以太原市区SO2、PM10浓度预测为例,选择气温、湿度、降水量、大气压强、风速和前5天的污染物浓度等10个参数训练BP神经网络,结果表明,BP神经网络的训练效果较好,预测结果与实际浓度显著相关,R2分别为0.988、0.976;结合太原市8个监测点位的污染物浓度预测值,运用GIS空间差值法绘出SO2、PM10的浓度分布预测图,该图与实际情况大体符合,并且与国控大气污染企业的分布显著相关,Pearson相关系数分别为0.969、0.949。  相似文献   

19.
The biogeochemical and ecological assessment of the industrial city territory including urban soils and trees was carried out. Chemical (macroelement and microelement) composition of the city soils, morphological and biochemical properties of the linden leaves, possible impact of de-icing salts on soil and tree state, the correlation between the content of trace elements, and the S-containing plant compounds (phytochelatins) were included in the assessment. It was found that concentrations of trace elements in the soils near road with intensive traffic are changed from the soils, located at a distance of 40–50 m from the road. They have higher concentrations of As, Fe, Mn, Se, and Sr and lower concentration of Zn. The linden leaves from the roadside were characterized by the increase in As, Cu, Fe, Zn, and Cr and sharp decrease in the Mn and Sr concentrations. The analysis of soil water extracts showed a slight decrease of pH and low content of Ca, Mg, K, and Na for the distant sites. The phytochelatin test of linden leaves was weakly effective as well as asymmetry degree study of leaf lamina. The main differences were observed in the damage symptoms of leaves (chlorosis and necrosis) and the content of pigments (chlorophyll and carotenoids). The biochemical and ecological assessment of soils and trees showed relatively satisfactory ecological state of the investigated area in Moscow. The data obtained shows the weak local impact of the application of de-icing salts and automobile emissions.  相似文献   

20.
The noise pollution is a major problem for the quality of life in urban areas. This study was conducted to compare the noise pollution levels at busy roads/road junctions, passengers loading parks, commercial, industrial and residential areas in Ilorin metropolis. A total number of 47-locations were selected within the metropolis. Statistical analysis shows significant difference (P < 0.05) in noise pollution levels between industrial areas and low density residential areas, industrial areas and high density areas, industrial areas and passengers loading parks, industrial areas and commercial areas, busy roads/road junctions and low density areas, passengers loading parks and commercial areas and commercial areas and low density areas. There is no significant difference (P > 0.05) in noise pollution levels between industrial areas and busy roads/road junctions, busy roads/road junctions and high density areas, busy roads/road junctions and passengers loading parks, busy roads/road junctions and commercial areas, passengers loading parks and high density areas, passengers loading parks and commercial areas and commercial areas and high density areas. The results show that Industrial areas have the highest noise pollution levels (110.2 dB(A)) followed by busy roads/Road junctions (91.5 dB(A)), Passengers loading parks (87.8 dB(A)) and Commercial areas (84.4 dB(A)). The noise pollution levels in Ilorin metropolis exceeded the recommended level by WHO at 34 of 47 measuring points. It can be concluded that the city is environmentally noise polluted and road traffic and industrial machineries are the major sources of it. Noting the noise emission standards, technical control measures, planning and promoting the citizens awareness about the high noise risk may help to relieve the noise problem in the metropolis.  相似文献   

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