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Changes in leaf surface structures of two avenue tree species caused by auto-exhaust pollution
Abstract
Effect of automobile exhaust emissions on two common avenue trees, Azadirachta indica A. Juss. and Polyalthia longifolia Benth. and Hk. has been studied with special reference to their cuticular and epidermal characteristics. In plants collected from heavy traffic density areas (HTDA) the epicuticular wax was severely damaged and its morphology altered. Significant changes in cuticular and epidermal structures were also observed in the two species and a two-fold increase in stomatal frequency was recorded. The lead content in HTDA plant leaves was considerably higher as compared to the plants growing along the road side in low traffic density areas (LTDA). While the surface structural changes were significant, the phenology of these plants remained unaffected by auto-exhaust pollution.
... Rajchidambaram et al. (1980) observed clogging of stomata, loss of one or both guard cells or total destruction of stomata apparatus caused by cement dust pollution in all the five species of flowering plants studied by them. Yunus et al. [26] noticed a conspicuous increase in frequency of stomata, percentage of abnormal stomata, larger stomatal openings and conspicuous circular striations in polluted population of Ricinus communis L. Leaves of Syzygium cumini L, showed marked decrease in epidermal cell size, increase in number of epidermal cells and stomata, necrotic lesions and death of epidermal cells [27][28][29]. Few common avenue plants as A. indica and P. longifolia were found with dust particles embedded in the wax crust of the leaves. Cuticles were disorganized and broken at the outer stomata ledge. ...
... Protein and starch content of the leaves which are very often being used for monitoring of air pollution, are also reduced on exposure to dusty environment [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31]. According to Borka [12], starch reduction is due to clogged stomata that might have inhibited the phosphorylation of sugars and consequently translocation from the assimilative leaves because of lowering of transpiration and hence over heating of leaves. ...
... Air particulates affect the overall growth and development of plants according to their physical and chemical nature (Gupta & Ghouse 1987). Air particulates also alter the morphology and anatomy of the leaves (Farooq et al. 2000, Pal et al. 2000, Shrivastava & Joshi 2002, Garg et al. 2000. Surface dust deposit may alter the optical properties of leaves, particularly the surface reflectance in the visible and short wave infra-red radiation range (Eller 1997, Hope et al. 1991, Keller & Lamprecht 1995. ...
... Leaf petioles are more efficient particulate impactors than either twigs (stems) or leaf lamina (Ingold 1971). Green belts reduce noise pollution (Pal et al. 2000, Fang & Ling 2005, Martinez Sala et al. 2006. The trees and shrubs have been identified as dust filters to check the rising urban dust pollution level in the area (Rai et al. 2010). ...
Industrialization has provided humanity with materials and social benefits. It has also brought in its wake up many unwanted substances and social problems. One of these problems is the degradation of the environment. The environment, upon which our life is most dependent, has fallen victim of pollution brought by the man himself through unplanned and unscientific development and mineral exploitation. Air pollution is an inevitable harmful by-product of rapid industrialization and urbanization that is responsible for a variety of deleterious effects on both human and plant communities. It has been a major environmental concern since the beginning of industrialization, resulting in a release of gaseous and particulate pollutants into the atmosphere. A relationship between traffic density and photosynthetic activity, stomatal conductance, total chlorophyll content and leaf senescence has been reported. Exposure of evergreen plants to air pollutants create many changes in physiological and biochemical parameters. Each plant species has a different ability to absorb and adsorb pollutants by their foliar surfaces, which is influenced by several biochemical, physiological and morphological characteristics. Rampant and uncontrolled use of fossil fuels in industries and transport sector has led to an increase in concentrations of the gaseous pollutants. Indian cities are facing serious problems of airborne particulate matter. Atmospheric particulate matter, which is a mixture of diverse elements, is of most concern in context of public health. Particulates may also cause a reduction in yield, change in photosynthesis and transpiration along with foliar injuries. The plant species which accumulate more dust onto their surfaces can act as buffer around industries and along roadsides. The present study deals with the plant-pollutant interactions and how the physical and chemical characteristics of plants vary with air pollution. It also throws light on how dust affects various plant species and what is the role of plants in dust accumulation. Nat. Env. & Poll. Tech. Website: www.neptjournal.com
... Damages caused by air pollutants to plants include chlorosis, necrosis, and epinasty (Katiyar and Dubey, 2000). Air particulates aff ect the overall growth and development of plants according to their physical and chemical nature (Gupta and Ghouse, 1987; Pandey et al., 1999), and morphology and anatomy of the leaves are altered (Gupta and Mishra, 1994; Trivedi and Singh, 1995; Somashekar et al., 1999; Singh and Sthapak, 1999; Farooq et al., 2000; Pal et al., 2000a; Shrivastava and Joshi, 2002; Garg et al., 2000 ). Surface dust deposits may alter the optical properties of leaves, particularly the surface refl ectance in the visible and short wave infrared radiation range (Eller, 1977; Hope et al., 1991; Keller and Lamprecht, 1995). ...
To assess the dust interception efficiency of some selected tree species and impact of dust deposition on chlorophyll and ascorbic acid content of leaves the present study was undertaken. The plant species selected for the study were Ficus religiosa, Ficus benghalensis, Mangifera indica, Dalbergia sissoo, Psidium guajava, and Dendrocalamus strictus. It was found that all species have maximum dust deposition in the winter season followed by summer and rainy seasons. Chlorophyll content decreased and ascorbic acid content increased with the increase of dust deposition. There was significant negative and positive correlation between dust deposition and chlorophyll and ascorbic acid content, respectively. Maximum dust interception was done by Dalbergia sisso and least by Dendrocalamus strictus. Thus plants can be used to intercept dust particles which are of potential health hazards to humans.
... Plants filter out pollutants from the air in three ways, viz. absorption by the leaves, deposition of particulate and aerosols on leaf surface, and fallout of particulate on the leeward (down wind) side of the vegetation because of the slowing of the air movement (Spitsyna and Skripal´shchikovaSkripal´shchikova, 1991; Varshney and Mitra, 1993; Singh et al., 1995; Rawat and Banerjee, 1996; Pal et al., 2000; Tomaševí c et al., 2005; Turner et al., 2005). The concept of green areas, green belt and urban forest can affect local and regional air quality by removing atmospheric pollutants and altering urban microclimates by lowering temperatures through shading and evapo-transpiration and may also lead to people spending a greater amount of time outdoors and being more healthy and physically active (Whitford et al., 2001; Tzoulas et al., 2007; Escobedo and Nowak, 2009). ...
Fly ash (FA) disposal creates problems in the form of land use, health hazards and hazards to entire ecosystems in the form of heavy metal pollution. These hazards are more pronounced in the vicinity of disposal sites where FA particles become airborne and are inhalable. Since plants can play an important role in reducing air pollution, the concept of green belt development in and around industrial areas has gained much attention in the recent past. In the present study certain traits of plant that have to be taken into account while planning a green belt for fly ash exposed area has been investigated. Ten plant species growing in the vicinity of FA handling area were selected. FA load on leaf surfaces and leaf surface morphology as a measure of FA trapping ability, and trace metal content of leaves as an indicator of trace element accumulating capacity was analyzed. Dust trapping capacity was found to be in order of Mussaenda frondosa > Haldina cordifolia > Pedilanthus tithymaloides cv. variegates > P. tithymaloides > Duranta erecta > Delonix regia > Anthocephalus cadamba > Mangifera indica > Polyalthia longifolia > Mimusops elengi. Metal accumulation index was found to be highest for H. cordifolia followed by M. frondosa. Results indicate that leaf surface morphology greatly determines dust trapping capacity of a particular species. Based on our observations we recommend certain factors that have to be considered while planning green belts around fly ash-handling areas at coal based thermal power plants.
... Relatively less studies investigated the effect of ambient air pollution i.e., a complex mixture of different types and concentrations of particles and gaseous pollutants in noncontrolled outdoor conditions on leaf wettability (Percy and Riding, 1978; Kupcinskiene and Huttunen, 2005). Erosion, fusion, cracking or any other injury of the leaf surface including ageing, hereafter called 'damage', can be observed using scanning electron microscopy (Cape, 1983; Pal et al., 2000; Sant'Anna-Santos et al., 2006), but this is a rather expensive method. Alternatively, leaf surface damage can be estimated by measuring drop contact angles on the leaf surface as a measure of leaf wettability (Fogg, 1947; Percy and Riding, 1978; Paoletti et al., 1998a). ...
This study evaluated the effect of urban habitat quality on the wettability of tree leaves. We measured leaf
wettability of five common tree species, i.e., Alnus glutinosa, Acer pseudoplatanus, Betula pendula, Quercus
robur and Sambucus nigra, in semi-natural and industrial urban habitats in the city of Gent (Belgium).
Possible seasonal variation was taken into account by measuring in late spring and in late summer. Drop
contact angle (DCA), and height over width ratio were measured on the abaxial and the adaxial leaf
surface as proxies for leaf wettability. The relative standard deviation for the height over width ratio was
higher than for the DCA, so that only the latter was considered further.
Habitat type significantly influenced leaf wettability: the DCA values of Q. robur leaves were significantly
lower in the industrial than in the semi-natural areas, in both June and September while, for S.
nigra, the DCA was in both sampling events significantly higher in the industrial areas. For the adaxial leaf
side, the differences between the considered habitats were more pronounced in June than in September.
The adaxial DCA of A. pseudoplatanus was significantly higher in June compared to September, while the
opposite held for abaxial values of A. glutinosa. We conclude that leaf wettability is potentially a good
indicator to point out differences in urban habitat quality, but selection of the most sensitive tree species
and the appropriate time of measuring is an important prerequisite.
... Therefore, the micromorphology of wax crystals has been regarded as a robust tool in angiosperm identification and classification (Barthlott et al. 1998;Meusel et al. 1999). However, some evidence of environmental factors (e.g., exhaust fumes, water deficit) affecting epicuticular wax has been reported (e.g., Pal et al. 2000;Kim et al. 2007), so this assumption must be viewed with caution. ...
Epicuticular wax on the leaves from nine cultivars of Phormium tenax was characterised to assess its possible usefulness as a diagnostic tool in cultivar identification. The selected cultivars were taken from the Rene Orchiston Collection in Dunedin Botanic Garden. Wax morphology on both leaf surfaces was examined using a field emission scanning electron microscope. Wax morphology was consistently more complex on the abaxial than the adaxial surface. Differences in wax morphology were noted among some cultivars: cv. Tapamangu had clumps of wax crystals orientated diagonally across the leaf width; cv. Whareongaonga had variable crystal morphology, but was dominated by transversely ridged rods; and cvs Ngutunui and Taeore were covered with a fissured wax layer, with crystals visible in the fissures. We concluded that wax crystal morphology may be useful as a diagnostic tool in cultivar identification. However, it remains to be determined whether the same cultivars growing at different locations would retain their wax crystal morphologies.
... Likewise, a number of studies have been done on the pollution effects on different aspects of plant life such as overall growth and development (Gupta and Ghouse, 1987;Saquib et al., 1992;Misra and Behera, 1994;Pandey et al., 1999), foliar morphology (Gupta and Mishra, 1994;Trivedi and Singh, 1995;Somashekar et al., 1999;Singh and Sthapak, 1999;Farooq et al., 2000;Pal et al., 2000;Shrivastava and Joshi, 2002), anatomy (Zafar, 1985;Arjunan et al., 1993;Garg et al., 2000;Singh, 2000), and biochemical changes (Balsberg-Pahlsson, 1989;Pandey and Sinha, 1991;Vyas et al., 1991;Budharaja and Agrawal, 1992;Tiwari and Patel, 1993;Krishnamurthy et al., 1994;Senapati and Misra, 1996;Pandey et al., 1999;Garty et al., 2001;Mashitha and Pise, 2001;Gavali et al., 2002). Pollution effects have been found to link the physiological response of plants to acceleration in the process of senescence (Lee et al., 1981;Kohert et al., 1986). ...
Vehicle derived pollutants as well as industrial emissions simultaneously release deleterious fine-grained particulates and magnetic particles into the atmosphere These magnetic particles are derived from the presence of iron (as impurities in fuels, industrial emissions, street dust, rock dust etc.), often a mix of strongly magnetic (magnetite-like) and weakly magnetic (haematite-like) iron oxides. Present review discusses the problem of particulate matter (PM) pollution, its environmental geomagnetic studies with special reference to biomagnetic monitoring through roadside plant leaves. Biomagnetic monitoring with the roadside plant leaves, is very recent thrust area in the field of PM pollution science. An overview of the researches on implications of environmental geo-magnetic studies is presented in this paper for sediments, street dust and vegetation. The concept of environmental magnetism as a proxy for atmospheric pollution levels has been reported by several researchers based on analysis of soils and street or roof dust; however, very few researches have emphasized the use of roadside plant leaves in monitoring the dust. Magnetic biomonitoring of pollutants by measurements taken from roadside tree leaves is potentially efficient and cost-effective. Finally, several case studies on biomagnetic monitoring in Indian subcontinent by our group have been mentioned in detail. Nevertheless, there is still paucity of focused research works in the multifaceted environmental dimensions of magnetic monitoring particularly biomagnetic monitoring of particulate pollution with roadside plant leaves which possess the potential to become a new frontier in the field of atmospheric science and technology.
... Ferenbaugh (1976) reported that cell sizes were smaller and intercellular leaf spaces reduced in leaves of Phaseolus vulgaris exposed to acid rain. Many authors were reported similar results of reducing the sizes of epidermis cells of the leaf blades in plants exposed to different levels of air pollutions (Ferenbaugh 1976;Pal et al. 2000;Aggarwal 2000). ...
Growth and development of the leaf blades of Acer tataricum in industrially contaminated environment Received: Abstract: During one vegetative season, the growth and the development of the leaf blades of Tatarian maple (Acer tataricum L.) from heavily polluted area has been studied. The region under investigation was contami-nated mainly with SO 2 , N x O x , Pb, Zn, and Cu etc. The aim of the study was to compare the growth and the de-velopment of the leaf blades of Acer tataricum L. (Tatarian maple) from polluted field with those from non-pol-luted. Base on this to assess its tolerance to polluted conditions of the atmosphere, as well as to look for adap-tive responses. The conducted study registered shorter time of the vegetative growth of the leaf blades in the commencement stages of the vegetative development. The leaves from polluted site had emergence approxi-mately two weeks earlier compared with these from the control area. Faster linear growth of the leaf surfaces in the commencement stages of the development had been noted for the trees from polluted field. The spongy mesophyll had been reduced, as well as the common thickness of the leaf blades of the tree plants from the contaminated region. The observed changes are regarded as adaptation of the plant to the polluted environ-ment, i.e. as tolerance.
... The manifested trend (smaller epidermal cells in the leaf blades of polluted trees) was registered at the first measurements on April and sustained during the complete development up to mature leaf. The similar results reduction in size of epidermal cells at polluted sites as compared to that at reference site is received in studies of the foliar epidermal traits from other authors (Ferenbaugh 1976;Aggarwal 2000;Pal et al. 2000). ...
Leaf blades of Norway maple (Acer platanoides L.), growing in heavily polluted industrial area have been studied for anatomical changes developed under the influence of the industrial contamination (with SO 2 , N x O x , Pb, As). The aim of the examination was to reveal the dynamics in the development of leaf blades and to trace the impact of the contaminated air on the leaf structure of Norway maple. The conducted study registered acceleration of the vegetative growth of the leaf blades that is manifested through approximately two weeks earlier appearance of leaves on the tree, faster linear growth and strength-ened the xeromorphic traits in the leaf structure of the tree plants from the contaminated region. The ob-served changes are regarded as adaptation of the plant to the polluted environment, i.e. as tolerance.
... Effect of automobile exhaust emissions on the two common avenue trees Azadirachta indica and Polyalthia longifolia has been studied with special reference to their cuticular and epidermal characteristics. In plants collected from heavy traffic density areas (HTDA) the epicuticular wax was reported severely damaged and its morphology altered with significant changes in cuticular and epidermal structures (Amit et al. 2000). The stress effects of motor vehicle exhaust gas (black carbon (BC), fine particles, VOCs and carbonyl compounds) resulted in an increase in concentrations of proline, glutamine, threonine, aspartic acid, glycine and phenylalanine and decreased concentration of arginine, serine, alanine and glycine in young needles of Norway spruce (Picea abies) seedlings (Viskari et al. 2000). ...
Effect of automobile polluted soil with five soil concentration (0 (Control), 25, 50, 75 and 100%) was observed on early seedling growth performance and biomass production of Neem (Azadirachta indica A. Juss). The treatment of 75% automobile polluted soil significantly (p < 0.05) decreased the seedling length (18.60 cm) of A. indica. The automobile polluted soil treatment with the concentration of 50% slightly increased the root length as compared to control. The automobile polluted soil treatment with the concentration of 25, 50, 75 and 100% negatively affected shoot length of A. indica as compared to control. The treatment of all concentration of automobile polluted soil progressively decreased the total leaf area A. indica as compared to control soil treatment. The automobile polluted soils also showed negative effects on biomass production of A. indica. The automobile polluted soil treatment at 25% concentration significantly (p < 0.05) affected shoot, leaves and seedling dry weight of A. indica as compared to control soil treatment. The order of relationship between production of A. indica's seedling dry weight and automobile polluted soil treatment was observed as root > shoot > leaves > total seedling.
... The road side plants play significant role in assimilation and accumulation of pollutants and act as efficient interceptors of airborne pollutants. Studies show that under polluted conditions, plants develop different morphological, physiological and anatomical changes (Inamdar and Chaudhari 1984 , Iqbal 1985, Gupta and Ghouse 1988, Gravano et al. 2003, Novak et al. 2003, Dineva 2004). Recently, adverse effects of urban air pollution on leaf architecture of plants have been studied by various workers (Kulshreshtha et al. 1994a, 1994b, Hirano et al. 1995, Sharma and Roy 1995, Carreras et al. 1996, Aggarwal 2000, Pal et al. 2000, Kaur 2004, Dineva 2006 ...
... It plays a major role reducing the pollution caused by vehicular movement [4] and also reduces concentration of CO2 in atmosphere in the form of biomass [5]. Some studies were conducted on the effect of vehicular pollution on avenue trees viz., Azadirachta indica and Polyalthia longifolia [6]. Moreover, the avenue trees have been drastically affected due to modernization and developmental projects in the developing cities [7]. ...
The avenue trees in NERIST campus are dominated by Grevillea robusta, Duabanga grandiflora, Mesua ferrea, Delonix regia, Mimusops elengi, Cassia siamea, Anthocephalus chinensis, Polyalthia longifolia, etc. The database of avenue trees were documented on various parameters like interspacing, crown height, crown width, etc. Of this, the crown height and crown width are important characteristics helpful in proper planning and management of avenue tree.
... The long term, lowconcentration exposures of air pollution produces harmful impacts on plant leaves without visible injury (Joshi et al., 2009). Several studies have been conducted to assess the effects of pollution on different aspects of plant life such as overall growth and development (Gupta and Ghouse, 1987;Misra and Behera, 1994), foliar morphology (Farooq et al., 2000;Pal et al., 2000;Shrivastava and Joshi, 2002;Gostin, 2009;Sukumaran, 2012), anatomy (Garg et al., 2000), and biochemical changes (Garty et al., 2001;Mashitha and Pise, 2001;Gavali et al., 2002;Rai et al., 2013;Rai et al., 2013;Rai and Singh, 2015;Rai, 2016a, , b). Effects of cement, petro-coke dust, fly ash, coal dust, automobile exhaust and other air-borne particulates on various morphological and physiological parameters in different plants were well-studied by many workers (Naidoo and Chirkoot, 2004a,b;Verma and Singh, 2006;Prajapati and Tripathi, 2008a,b,c,d,e,f;Saha and Padhy, 2011;Rai et al., 2013;Rai and Panda, 2014;Rai and Singh, 2015;Rai, 2016a, , b). ...
Air pollution is one of the serious problems world is facing in recent Anthropocene era of rapid industrialization and urbanization. Specifically particulate matter (PM) pollution represents a threat to both the environment and human health. The changed ambient environment due to the PM pollutant in urban areas has exerted a profound influence on the morphological, biochemical and physiological status of plants and its responses. Taking into account the characteristics of the vegetation (wide distribution, greater contact area etc.) it turns out to be an effective indicator of the overall impact of PM pollution and harmful effects of PM pollution on vegetation have been reviewed in the present paper, covering an extensive span of 1960 to March 2016. The present review critically describes the impact of PM pollution and its constituents (e.g. heavy metals and poly-aromatic hydrocarbons) on the morphological attributes such as leaf area, leaf number, stomata structure, flowering, growth and reproduction as well as biochemical parameters such as pigment content, enzymes, ascorbic acid, protein, sugar and physiological aspect such as pH and Relative water content. Further, the paper provides a brief overview on the impact of PM on biodiversity and climate change. Moreover, the review emphasizes the genotoxic impacts of PM on plants. Finally, on the basis of such studies tolerant plants as potent biomonitors with high Air Pollution Tolerance Index (APTI) and Air Pollution Index (API) can be screened and may be recommended for green belt development.
... India has 23 major cities of over 1 million people and ambient air pollution levels exceed the WHO standards in many of them [5]. The single most important factor responsible for deterioration of air quality in the cities is the exponential increase in the number of vehicles [11]. Vehicular pollution contributes to 70% of Search And Research visibility, fog, haze rain, cloudiness and consequent effects on sports/recreation, tourism, travel, accidents, human comfort, power generation and transmission, scheduling of load shedding and even crime. ...
... The manifested trend (smaller epidermal cells in the leaf blades of polluted trees) was registered at the first measurements on April and sustained during the complete development up to mature leaf. The similar results reduction in size of epidermal cells at polluted sites as compared to that at reference site is received in studies of the foliar epidermal traits from other authors (Ferenbaugh 1976;Aggarwal 2000;Pal et al. 2000). ...
... [25] Quantitative analysis of stomata parameters showed that samples from the study site had higher number of stomata per unit area than those from control site while samples from control site had higher values for stomata size and pore size. Similar results have been reported by previous authors [16,26,27]. Dust particles from quarrying sites tend to clog stomatal openings and thereby decrease the rate of gas exchange. ...
This present study assessed oxidative stress and air pollution tolerance of selected broad leaved trees in the vicinity of a quarry site at Ugwuele, Uturu by assessing some physiological and biochemical properties of their leaves. Three trees Alchornea cordifolia, Nauclea latifolia and Newbouldia laevis growing in the quarry site were randomly selected for this study. The result of quantitative analysis of foliar parameters shows that the epidermal cells of A. cordifolia and N. laevis were completely deformed and the guard cells became plasmolysed. The pore length, width and area had higher values at control samples and were significantly different (P<0.05) when compared with those from the study area. Significant differences (P<0.05) were observed in pH and total chlorophyll content of the evaluated plants. N. laevis had the highest air pollution tolerance index of 22.34, thus making N. laevis the most tolerant to air pollution among the studied plants. Based on the findings of this study, N. laevis tree is recommended for bio-mitigation of air pollution from the quarry environment.
... Erosion, fusion, cracking or any other injury of the leaf surface including ageing, hereafter called 'damage', can be observed using scanning electron microscopy (Cape, 1983;Pal et al., 2000;Sant'Anna-Santos et al., 2006), but this is a rather expensive method. Alternatively, leaf surface damage can be estimated by measuring drop contact angles on the leaf surface as a measure of leaf wettability (Fogg, 1947;Percy and Riding, 1978;Paoletti et al., 1998a). ...
... In another study stomatal abundance and increase in epidermal cells in leaves of Azadirachta indica and Polyalthia longifolia (Pal et al. 2000), Cassia siamea (Aggarwal 2000), and Nyctanthes arbortristis, Quisqualis indica and Terminalia arjuna (Rai and Kulshreshtha 2006) on SO 2 exposure have been found. Along with this, reduced stomata and epidermal cells size with exposure to SO 2 has also been found from other researchers' works (Aggarwal 2000;Kaur 2004;Dineva 2006). ...
Our health is closely related to our environment, such that a healthy environment brings healthy living and vice versa. Pollution due to air is a prime environmental aspect contributing to the burden of different diseases in human and also has considerable economic impact. The total air pollution accounts approximately 7 million deaths globally. Pollutants produced as combustion of particulate matter have demonstrated a time-series effect on human health. The size of inhalable particulate matter (PM10 and PM2.5) affects the mortality and morbidity upon short- and long-term exposure among all population, with highest effect on elderly individuals. Exposure to these pollutants produces the pathological alteration, such as increased inflammatory response, systemic oxidative stress, cardiovascular stress, and change in pulmonary autonomous nervous system activity. These molecular pathological events trigger several pulmonary and cardiovascular manifestations in human. From epidemiology point of view, it has been explored that among different air pollutants, particulate matter, ozone, carbon monoxide, nitrogen dioxide and sulfur dioxide are the major ones. The highest mortality is mainly observed in Asian populations as compared to Europeans and Americans. The top ten countries with the highest mortality are China, India, Pakistan, Bangladesh, Nigeria, the United States, Russia, Brazil, and Philippines, respectively. In this chapter, we reviewed different PM exposure-based epidemiological studies with more focus on high ambient Total Suspended Particulate (TSP) levels. It has also been found that overall absolute risk for mortality due to PM exposure is higher for cardiovascular compared to pulmonary disorders in case of both acute and chronic exposures.
... Stomatal size Metcalfe and Chalk (1988) and Beerling and Woodward (1997) (Amit, 2000;Ogunkunleet al., 2013). The decrease in the stomatal size may also be an evasion mechanism against the suppression effect of pollutants on physiological activities such as photosynthesis and also portends quicker response to external stimuli (Hetherington and Woodward, 2003;Verma et al., 2006). ...
Production activities by cement factories pollute the atmosphere with cement dust. Studies have indicated that plants growing around cement factories absorb these pollutants through foliar surfaces. This study investigated the leaf epidermal responses of Abelmoschus esculentus, Zea mays, Mangifera indica and Carica papaya growing around Obajana cement factory (OCF) in Kogi state to cement dust pollution. Samples were collected 1-3km to the east, north and west axes of the factory. A total of 72 samples were collected from the vicinity of the factory site and prepared for microscopic observations following leaf maceration method. Control samples were collected from an agrarian community, a distance of about 47.5 km from the factory. Basic descriptive statistics revealed marked variations in stomatal complex type (SCT), trichomes density(TD), stomatal density (SD) and stomatal size (SS) of samples collected from the vicinity of the cement factory and samples collected from the control site.Abelmoschus esculentus was most impacted while Zea mays was least impacted by the cement dust pollution. The observed modifications in epidermal features expressed as decreased SS, increased TD and SD in plants growing around the cement factory are anatomical adaptations for survival in their cement dust laden environment. These alterations in anatomical features of the investigated species are majorly adaptations to prevent foliar damage by cement dust, thus could serve as bio indication of cement dust pollution.
... Several studies(Shan et al., 1996) suggest that low concentration of air pollutant may influence stomata indirectly through damage to the subsidiary cells or the epidermal cells that change the cell wall structure. Leaves indicate temporary pollution(Bass and Bauch, 1986; Fritts, 1976), which are the most visible and easily observable change occur in the micro-morphological parameters of the plant like change in the trichome density, stomata frequency and density, thickness of cuticle and toughness of epidermal cells are some of the associated changes(Pale et al., 2000). Thus plants are very sensitive to pollutions which can be used as indicators of air ...
Air pollution has become a serious environmental concern which is a major problem of Kathmandu Valley. The plants growing along the roadsides of the Kathmandu are under stress. The dust depositions on the leaves of shrubs were adversely affected by air pollution. It was found that dust particles affect leaf biochemical parameters which have changes micro-morphological symptoms. The study deals visible changes in the micro-morphological structure like specific leaf area, size of stomata, the thickness of epidermis and cuticle of leaves of Ageratina adenophora and Lantana camara investigated under polluted and control site (relatively less polluted area) of Kathmandu valley. Results showed that the plant species growing in a polluted site exhibited the significant reduction in the size of stomata, a thickness of the epidermal layer, a thickness of cuticle and the specific leaf area but the density of stomata increases in the polluted site as compared to the control site. Reduction in various parameters of two shrub species studied at three sites clearly indicates the deleterious effect of air pollution on plant health. It is concluded that vehicular emission had a significant effect on micro-morphological changes.
... Several studies(Shan et al., 1996) suggest that low concentration of air pollutant may influence stomata indirectly through damage to the subsidiary cells or the epidermal cells that change the cell wall structure. Leaves indicate temporary pollution(Bass and Bauch, 1986; Fritts, 1976), which are the most visible and easily observable change occur in the micro-morphological parameters of the plant like change in the trichome density, stomata frequency and density, thickness of cuticle and toughness of epidermal cells are some of the associated changes(Pale et al., 2000). Thus plants are very sensitive to pollutions which can be used as indicators of air ...
Air pollution has become a serious environmental concern which is a major problem of Kathmandu Valley. The plants growing along the roadsides of the Kathmandu are under stress. The dust depositions on the leaves of shrubs were adversely affected by air pollution. It was found that dust particles affect leaf biochemical parameters which have changes micro-morphological symptoms. The study deals visible changes in the micro-morphological structure like specific leaf area, size of stomata, the thickness of epidermis and cuticle of leaves of Ageratina adenophora and Lantana camara investigated under polluted and control site (relatively less polluted area) of Kathmandu valley. Results showed that the plant species growing in a polluted site exhibited the significant reduction in the size of stomata, a thickness of the epidermal layer, a thickness of cuticle and the specific leaf area but the density of stomata increases in the polluted site as compared to the control site. Reduction in various parameters of two shrub species studied at three sites clearly indicates the deleterious effect of air pollution on plant health. It is concluded that vehicular emission had a significant effect on micro-morphological changes.
An investigation on the seasonal variation in dust accumulation on leaves and leaf pigment content of six plant species of mixed habits was carried out at the side of the National Highway (NH 6) at Sambalpur, Orissa, India. The plants selected for study were Pongamia pinnata, Tabernaemontana divaricata, Ipomea carnea, Ficus relogiosa, Ficus benghalensis, and Quisqualis indica. The observed trend of dust accumulation was in the order T. divaricata>I. carnea>P. pinnata>F. religiosa>F. benghalensis>Q. indica. One-way analysis of variance showed significant difference in dust accumulation among plant species (F1 = 4.674, P < 0.01) and between seasons (F2 = 9.240, P < 0.01). It was seen that dust load increases with increasing number of vehicles using the highway (major emission source). The result shows significant correlation (negative) between dust load and pigment content in summer and rainy season.
The COVID-19 pandemic has affected many commercial activities around the globe, and the construction industry is unquestionably on the wrong end of the curve. Many construction projects are delayed and are already in a huge loss. The stakeholders of construction projects are left clueless, wondering about the new normal. During this uncertain situation, the construction industry is facing a sudden surge in the number of claims being submitted. This research is intended to understand the claims and dispute management aspects of construction, to find the frequent type of claim due to the pandemic and to address the procedure and provisions to claim under FIDIC contracts and Indian Contract Act. From the questionnaire survey, Extension of Time claim turned out to be the most frequent claim, and the procedure adopted for successful claiming of EOT has been explained with a sample project case.
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 8.0km range and a reference site was selected in eastern direction at a distance of 22.0km.
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 (SO2), nitrogen dioxide (NO2), 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 (SO42--S\textnormal{SO}_{4}^{2-}-\textnormal{S}) contents were measured. Ambient SO2, NO2, 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 SO42--S\textnormal{SO}_{4}^{2-}-\textnormal{S} in leaf tissue showed significant positive correlation with ambient SO2 concentration at all the sites. At the same time, SO42--S\textnormal{SO}_{4}^{2-}-\textnormal{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.
Efficient project delivery is essential in the Indian construction industry. This efficiency can be achieved by reducing errors in construction projects to minimize cost and time. The chances of errors in the designing stage are high, which can lead to construction delays and other claims. BIM (Building Information Modeling) is a technology that can reduce not only human efforts but also the likelihood of errors. BIM is emerging rapidly and transforming the Indian real estate and construction sectors. This study verifies the BIM functionalities that help reduce the design and human errors that occur at various intervals of the project. This study also helps BIM users identify possible errors and their perceived severity, which can occur while working in a construction environment and avoiding these errors by applying BIM functionalities to achieve optimum time and cost. The quantitative technique was difficult to carry out for evaluation. Hence, the qualitative approach for research is carried out based on the perception shared by construction professionals working on the BIM platform. Ineffective design coordination between the design and planning teams, detailing errors, clashing of elements, and lags in most up-to-date information were found to be the most severe errors that affect the project. The analysis explains the seven functionalities that were beneficial in reducing errors. Functionalities with similar natures of reducing errors were clubbed into compound clusters. Although quantity take-off was not very beneficial, it formed a greater number of clusters with other functionalities. Among several functionalities, the natures of the coordination model and work-sharing with a central cloud database were more similar in avoiding chances of errors. More attention is needed on technologies and software that will help reduce such errors. Training on BIM-based software is essential for the Indian construction industry to utilize effective project management systems and reduce claims.
Phytoremediation is an environment friendly and sustainable way of restoration of contaminated land from trace metals, pesticides and other industrial dangerous pollutants. This technique distinguishes a different mechanism for reduction of environmental pollution from industrial waste. The variety of plants grown in contaminated areas has efficiency to develop a metabolism in various parts (leaf, stem, roots) for the phytoremediation of heavy metals and pesticides. The use of transgenic plants promotes the phytoremediation technology for the improvement of remediation in contaminated areas. The concept of using green plants for phytoremediation enhances the potential of soil for restoration and in achieving UN‐SDGs. The traditional methods have various side effects and loopholes. Thus, the chapter provides the techniques used in the application of phytoremediation and sustainable approach for the restoration of contaminated areas. In order to increase the phytoremediation potential, further research is needed in contaminated areas where industrial waste is dumped.
Aerosols are the liquid, solid and mixed suspension of heterogeneous chemical particles that remain scattered in the environment. It absorbs solar radiation which affects the physiological features and survival rate of plants. In recent years, the effect of aerosol on the plant's physiology and morphology has been observed with more depth due to which new insights and a wealth of new knowledge and data have been obtained. Aerosol particles absorb incoming solar radiation and indirectly affects plant productivity (Cohan et al, 2002). This paper provides a complete overview of Surface temperature recorded from January 1948 to April 2020 of Uttarakhand State, India which has resulted in a 5% increase every decade. Various studies have suggested that increasing temperature increases the adverse effects of SO2 on plant physiology (Narby et al, 1981, Rogalaski et al, 2014). The paper highlights the first report from the foothills of Uttarakhand valley, regarding the impact of lockdown on the release of SO2 from (23 rd March 2020 to May 21 st , 2020). Aerosol particles affect the plant's system after deposition from the atmosphere. Different experimental studies showed that the aerosol deposition on the surface of the leaf give rise to the leaf fall, stomatal plugging, and intrusion with the closure of stomata (Hirano et al. 1995, Thompson et al 1984, Song et al, 2015). The deposition of aerosol on the leaf surface can cause elevated leaf temperature which leads to an increase or decrease in the net rate of photosynthesis. Stomatal conductance and net photosynthetic rate declined overtime at elevated particulate matter, and the rate of decline became more expeditious with the increasing amount of deposition of particulate matter. The deposition of dust particles on the surface of leaf reduces the stomatal size which leads to the stomatal closure and decrease in the conductance of stomata (Yunus et al. 1979, Gupta et al. 2016 (b)). This review provide a summary of the current information on the adverse impact of aerosols on the plant's physical states like plant growth, plant productivity, photosynthesis, transpiration, and its effect on plant active phytoconstituents.
Environment plays a crucial role in the physiological processes of plants. The numerous biotic and abiotic stresses in the plant habitat trigger complex responses in vital processes like photosynthesis, respiration and stomatal function. In this chapter we discuss the effect of various air pollutants on the stress physiological parameters. These studies are crucial because one of the major responses to plant pollutants is the inhibition of photosynthesis. This inhibition of photosynthesis not only alters the growth pattern and longevity but also changes plant phenology. Besides, assimilation of pollutants into the plant processes ultimately leads to their inclusion in the animal community. All this leads to a vicious cycle wherein the ecological factors suppress plant growth and in turn plants hamper the ecology. In this chapter we have also reviewed and highlighted the mechanistic aspect of the pollutants on the vital physiological parameters. The major pollutants which are emphasized are sulphur dioxide (SO2), nitrogen oxides (NOx) and ozone (O3) while physiological parameters reviewed are stomatal conductance, photosynthesis and respiration and photorespiration. These physiological processes are important parameters in governing growth and health of plants. Because all the natural processes are cyclic in nature, it is pertinent to observe that the stress in plants caused by the pollutants also directly and indirectly affects the human population.
The particulate pollution has always been a matter of great concern because of its adverse effect on human and plant population. In the present global environmental scenario, this problem has become increasingly severe. The particulates and gaseous pollutants, alone and in combination, can cause serious setbacks to the overall physiology of plants. Results from numerous investigations of human respiratory and other diseases have shown a consistent statistical association between human exposures to the outdoor levels of particulates or dust and adverse health impacts. These hazards are more pronounced in the vicinity of industries where these particles become air-borne and inhalable. Research has shown that plant leaves being the main receptor of particulate pollution can act as biological filters, removing large quantities of particles from the urban atmosphere. This physical trait can be used to determine the level of particulate pollution in the surroundings, as well as the ability of individual plant species to intercept and mitigate particulate pollutants. In the present study, fifteen plant species (11 trees and 4 shrubs) growing around the Rourkela Steel Plant (RSP) area were selected. Particulate or dust load on leaf surfaces and leaf surface morphology as a measure of dust trapping ability of leaves were analysed. The plant species such as Alstonia scholaris, Anthocephalus indicus, Cassia auriculata, Cassia siamea, Lagerstroemia speciosa, Mimusops elengi, Peltophorum inerme and Tabebuia aurea were found to have high dust capturing capacity; Albizia lebbeck, Bougainvillea spectabilis, Ficus religiosa, Swietenia mahagoni and Thevetia nerifolia have medium, while species such as Caesalpinea pulcherima and Delonix regia have low dust capturing capacity. Results also indicate that leaf surface morphology greatly determines the dust trapping capacity of a particular plant species.
Rise in population, urbanization and expansion of the Jammu city has resulted in the considerable increase of vehicular traffic. Vegetation in the urban areas, which function as breathing lungs for the city environment, show symptoms of air pollution stress. The present paper is an attempt to look at the effects of vehicular pollution on some of the parameters of leaf micromorphology, anatomy and chlorophyll contents of Syzygium cumini L. All the parameters registers decrease in their values, except for some of the morphological and anatomical ones, at the polluted site as compared to reference site and difference has been observed to be statistically significant at 0.5 level of significance.
The quality of air with respect to SPM, SO2 and NO2 of the various traffic crossings of Jammu city and New University Campus - near main entry gate and inside campus, has been assessed. The effect of air pollution has been recorded on the various parameters of the leaves - leaf colour and area, length, breadth and L/B ratio of stomata, stomatal frequency and stomatal index of some plant species viz., Morus alba, Ipomea cornea, I. cairica, Ficus relegiosa, Thevitia peruviana, Bougainvillea sp. growing along the roadside. The result indicate that the colour of the leaves has changed from bright green to dull green. Leaf area, length and breadth of the stomata have been observed to decrease in all the studied species at the polluted site. Stomatal frequency and stomatal index (SI) has decreased at the polluted site in all the species except for Thevitia. However, in Bougainvillea sp. the stomatal frequency has registered increase in its value.
Monitoring of exhaust emission characteristics, particularly Carbon Monoxide and hydrocarbons concentrations of 957 petrol driven vehicles was conducted in Rewa city of Madhya Pradesh. The results indicate that mean emissions from four and three wheelers exceeded the standard limit of CO and hydrocarbons. Although, the mean emissions of two wheelers also exceeded the standard limit of hydrocarbon, only few types were found to exceed the CO permissible limit. Exhaust emission from Hero Honda was fond to have lowest concentration of CO and hydrocarbon. Maximum number of four wheelers were found to disobey the standard CO and hydrocarbon emission to be followed by three and two wheelers.
The QS is a major key player in a construction project. The involvement of QS in different phases of a project is obligatory in order to meet the project requirement. QS acts as a ‘Financial police’ for a project. The role of a QS is different when working for different organizations such as consultant and main contractor. In order to know the involvement of QS in each project phase when working as a consultant QS and main contractor QS, this study is carried out through data collection by means of a survey done with the QS professionals working currently in the industry. The findings from the survey revealed that the role of the QS working in a consultant and main contractor organization is much different w.r.t to requirement, work and project. The required competencies, skills and experience will also matter when working in the industry as professional QS. Various software tools used by the QS were also found out during this study. Knowledge of the role of a QS in an entire project lifecycle when working for different organizations like consultant and main contractor will help in understanding the things in better way w.r.t to services to be provided, activities, objectives and scope stated for the project which in turn will reflect the professional way of approaching and working in the industry. The study will also be useful to civil engineering graduates who are willing to opt for the quantity surveying profession, industry quantity surveying professionals, educational institutions, service providers and other stakeholders in the construction industry.
Air pollution originating from rapid industrialization, urbanization, population growth and economic development has disturbed the urban ecosystems of ecologically sensitive regions like the Indo-Burma hot spot, and they are under severe air pollution stress with limited resources to collect data on what is happening. Air pollutants comprised of both particulate matter (PM) and gaseous pollutants may cause adverse health effects in human, affect plant life and impact the global environment by changing the atmosphere of the earth. It is now well established that urban PM may also contain magnetic particles along with other air pollutants. Biomonitoring of PM through magnetic properties, known as biomagnetic monitoring, measures the magnetic parameters of dust loaded plant leaves, giving a new opportunity to monitor. Compared to existing conventional technologies, biomagnetic monitoring is an eco-friendly technique perfect in urban areas. Biomagnetic Monitoring of Particulate Matter reviews the issues with PM and the potential of these methods to on tropical vegetation on a variety of flora which represent the biodiversity of the Indo-Burma Hot Spot. Bio-magnetic Monitoring of Particulate Matter gives a comprehensive overview of the issue of particulate pollution and monitoring. Cases of magnetic biomonitoring across different environments are included to demonstrate this emerging technique as a way to measure particulate pollution. Coverage includes a comparison to other techniques as well as why it works well ecological diverse developing areas which are data scarce, like the Indo-Burma Hot Spot. A review of the detrimental health impacts of Particulate Matter reinforces the importance for this type of data to be available universally.
The body of information presented in this paper is directed to individuals concerned with the state of our knowledge on lead uptake and translocation by plants and its subsequent effects. Lead, a non-essential element, is taken up by many plant species primarily via their roots. Large amounts of lead are deposited on plant foliage and most remains as a topical deposit but foliar uptake has been demonstrated. To date it has been assumed that soil lead levels above 1000 ppm are required to cause observable plant effects. Environmental variables, plant age, and species are very important determinants of lead uptake. The few studies done with plant age and speciation, however, provide no clear generalization. Increasing soil lead availability increases plant uptake. Plant uptake decreases with increasing soil phosphorus, organic content, and pH. The lack of observable lead intoxication of native and agricultural plants is surprising in light of evidence that lead concentrations as low as 1 ppm have a profound effect on events associated with photosynthesis and respiration, this has been explained because even though large amounts of lead may be taken up by plant roots they are immobilized by dictyosome vesicles and deposited in the cell wall. It has been suggested that a similar process is operative throughout the plant. The extant data provide no basis for any fear that lead is an imminent dietary hazard to man.
Cuticular and epidermal features of leaves of two common plant species namely, Lantana camara L. and Syzygium cuminii L. (Skeels.), growing in polluted and healthy (control) environments were studied under light and scanning electron microscopes. Polluted leaf samples were collected from the plants growing near a diesel generating set used in running a tube well.The study shows that in polluted populations of Lantana camara, the trichome frequency had increased four fold. In Syzygium cuminii, the stomatal openings were filled with dust and a tendency towards callus formation was also observed. The epidermal cells were comparatively thick walled and walls were broken at certain places.The changes observed in the cuticular and epidermal features of polluted populations of the investigated species indicate their significance as bioindicators of atmospheric pollution.
A comparative study of the physico-chemical properties of soil, leafmetal content and foliar surface traits in Lagerstroemia parviflora(L.) Roxb. plants, growing in an iron-rich mineralized and anon-mineralized area was carried out. Metal accumulation wasmaximum in summer; in the peak growing season, it declined duringthe rainy season but picked up again in winter. In leaves sampled froma mineralized region, epidermal cells were much smaller in size buthigher in number per unit area. Changes in the number and size of glandular papillae were also observed. Characteristic non-glandular,elongate trichomes with acute tip were also recorded in mineralizedpopulations. Scanning electron microscopic examination of the foliarsurface configuration revealed distortions in epicuticular wax structuresand wider cuticular striations with typically parallel arrangement inthese populations.The present study shows that high Fe-accumulation in leaves of L.parviflora during the exponential growth phase as well as changes inthe epicuticular structures may be indicators of metal stress in the populations of the mineralized area.
In maize chloroplasts, lead chloride causes inhibition or stimulation of photosystem II activity depending on the pH of the reaction media. At pH 7.8, an inhibition of 16 to 39% with 0.75mM to 9mM PbCl2 is observed. At pH 6.5, however, a stimulatory effect of 20% is observed with 9mM PbCl2; this effect is not due to the uncoupling of photophosphorylation, or to the ability of PbCl2 to donate electrons to photosystem II. On the basis of other data, reported here, a common site of inhibition between water and Z (the primary electron donor of photosystem II) for lead treatment and Tris-washing (0.8M, pH 8.0) of chloroplasts is suggested.Furthermore, lead salts (0.9mM) at both pH 6.5 and 7.8 induced about 20% inhibition of the variable chlorophyll a fluorescence even in the presence of 10 μM 3-(3,4 dichlorophenyl)1,1 dimethylurea. Room temperature and 77°K chlorophyll a emission spectra show an increase in the ratio of pigment system I to II fluorescence upon the addition of lead salts at both pHs—an opposite effect to that induced by salts of other divalent ions (e.g. Mg). Lead salts (0.9mM to 9mM) cause 10 to 20% increase in the 540 nm absorbance change, reflecting a decrease in spaces between thylakoids, over that of untreated chloroplasts. Lead-induced conformational changes in thylakoid membranes of chloroplasts, leading to change in energy distribution between pigment systems I and II, is suggested to explain the above results.
The changing levels of SO2 and Pb in the air and vegetation, along ten road transections of Lucknow city (having varying traffic densities) have been investigated, with a view to authenticate a possible correlation between SO2 and Pb concentration in air and sulphate and lead accumulation in the foliage of avenue trees. The study showed that the road transection at Alambagh (traffic density 4835 for 2 h) revealed the highest level of pollutants (SO2, 202 µg m(-3); SPM, 1080 µg m(-3); and lead, 2.96 µg m(-3), 2 h average) in air, as well as in the foliage of plants, whereas the road stretches with less traffic density correspondingly showed lower levels of pollutants. Pb and sulphate in leaves were found to be positively correlated with Pb and SO2 pollution in the air. Results suggest that Dalbergia sissoo and Calotropis procera are the ideal plant species to monitor as indications of Pb and SO2, respectively, in the air.
A simple, inexpensive technique is described for detailed monitoring of airborne metal pollution using Sphagnum moss suspended in fine nylon hair-nets from natural vegetation. The technique was employed to monitor pollution, month by month, at forty-seven sampling points over a large area around a Zn and Pb smelting complex at Avonmouth, near Bristol. Maps of the area were constructed by computer, depicting the levels and patterns of distribution of Zn, Pb, and Cd collected by the moss-bags. The results are related to wind data, localised climatic conditions and topography. The reliability and practical significance of this simple biological monitoring technique is discussed, with particular reference to the collection and retention of metals by natural vegetation. Comparison is made between moss-bags and other standard monitoring devices.
The surface structure of Aesculus hippocastanum leaves from air-polluted and control areas was examined with the scanning electron microscope. Small folds, present in the outer epidermal cell walls of normal leaves, were absent in leaves from air-polluted trees. Stomata of leaves from polluted areas had an abnormal appearance; however, they were not occluded by dust particles. Thin sections of both types of leaf also revealed remarkable differences in thickness and structure of the outer epidermal cell walls.
Fractionation of soil Cd, Pb, Zn, and Cu by extraction with 0.05 M CaCl2 (CA-Me), 2.5% acetic acid (AAC-Me), 0.1 M sodium pyrophosphate (PYR-Me), ammonium oxalate pH 3.25 under ultraviolet radiation (OX-Me), and HNO3- HClO4 mixture (RES-Me), was carried out on polluted and non-polluted soils collected from the Odda region, Norway. The relationships between different Me-fractions and between Me-fractions and some soil variables were statistically examined. The results confirmed an equilibrium relationship between the different Me-fractions. The data indicated a strong influence of soil pH on the distribution of the CA-Me fraction. There was also an apparent association between soil organic matter and PYR-fraction, and between the so-called free iron and manganese and OX-fractions. Similarities in the chemical behavior in soils between Cd and Zn and between Pb and Cu were noticed.
The in-vehicle concentrations of 24 gasoline-related volatile organic compounds (VOCs) and three criteria air pollutants, ozone, carbon monoxide, and nitrogen dioxide, were measured in the summer of 1988, in Raleigh, NC. Two four-door sedans of different ages were used to evaluate in-vehicle concentrations of these compounds under different driving conditions. Factors that could influence driver exposure, such as different traffic patterns, car model, vehicle ventilation conditions, and driving periods, were evaluated. Isopentane was the most abundant aliphatic hydrocarbon and toluene was the most abundant aromatic VOC measured inside the vehicles. In-vehicle VOC and CO concentrations were highest for the urban roadway, second highest for the interstate highway, and lowest for the rural road. The median concentration ratio of urban/interstate/rural for each VOC was about 10/6/1. No differences in in-vehicle VOC concentrations were found between morning and afternoon rush hour driving, but higher in-vehicle ozone and NO2 concentrations were found during afternoon driving. In-vehicle VOC levels were lowest with the air conditioner on and highest when the vent was open with the fan on. The in-vehicle/car exterior concentration ratio for VOCs, CO, and NO2 was slightly higher than 1. The VOC concentration measured by a pedestrian on the urban sidewalk was lower than the in-vehicle measurements but higher than the fixed-site measurements on urban roadways 50 m from streets. The VOC measurements were positively correlated with the CO measurement and negatively correlated with the ozone measurement.
The changing levels of lead (Pb) in the soil and vegetationalong two National Highways near Lucknow, India, wereinvestigated. The pattern of Pb deposition, as reflected bysoil Pb burdens, showed decrease in concentration withincreasing distances from the road margins. At both the sitesPb concentration was above background concentration even atthe soil core depth of 15 cm. Oryza sativa, Colocasiaesculentum, Luffa cylindrica and Cynodon dactylonplants contained a high mean concentration of Pb over theirrespective controls, with more accumulation in the undergroundportions of the plants. Milk samples, collected from cattlethat normally graze on the roadside pasture-lands dominatedby Cynodon dactylon, contained Pb at an elevatedconcentration.
There is increasing public concern about health effects resulting from ingestion of food containing toxic metals such as Cd and Pb. For example, a wide range of metabolic disorders and neuropsychological deficits in children have been noted, and chronic exposure to Cd has been linked to kidney failure and bone disease. The potential harm posed by the uptake of heavy metals such as Cd and Pb by plants is dependent on their abundance, mobility and bioaccumulation. Plant uptake of heavy metals was also influenced by soil pH. There is a linear relationship between soil concentrations of heavy metal and concentrations in vegetation around a zinc-lead tailing pond. The ability of the soil to retain metals depends on several factors; pH, cation exchange capacity (CEC), organic matter content, and their specific geochemical properties. Overall, the metal burden of a crop depends on: (a) uptake via the root system; (b) direct foliar uptake and translocation within the plant; and (c) surface deposition of particulate matter. Numerous studies have been conducted with agronomic crops regarding heavy metals in soils and plant uptake from sewage sludge, but only a few studies have dealt with the uptake of heavy metal mixtures in vegetables. This paper reports on germination/emergence, biomass and uptake of Cd and Pb in lettuce and radish grown in a loam soil spiked with known mixtures of CdCl{sub 2} and Pb(NO{sub 3}){sub 2}. Lettuce and radish have been used in this study because they are among the two groups of vegetable crops (leafy and root) consumed by humans. Also, earlier studies have reported that lettuce and radish bioaccumulate Cd and Pb from heavy metal polluted soils. 38 refs., 7 tabs.
In recent years a substantial research effort has focused on the links between particulate air pollution and poor health. As a result the PM10 value has been set as a measure of such pollutants which can directly cause illness. Due to their large leaf areas relative to the ground on which they stand and the physical properties of their surfaces, trees can act as biological filters, removing large numbers of airborne particles and hence improving the quality of air in polluted environments. The role of vegetation and urban woodlands in reducing the effects of particulate pollution is reviewed here. The improvement of urban air quality achieved by establishing more trees in towns and cities is also illustrated.