Evaluation of air pollution tolerance index of selected plant species along roadsides in Thiruvananthapuram, Kerala

To develop the usefulness of plants as bioindicators requires an appropriate selection of plant species which entail an utmost importance for a particular situation. In the present study a periodic evaluation of air pollution tolerance index [APTI] of selected tree species such as Polyalthia longifolia, (Sonner) Thw., Alstonia scholaris, R. Br., Mangifera indica, L., and shrubs Clerodendron infortunatum, L., Eupatorium odoratum, L., and Hyptis suaveolens, (L.) Poit., growing adjacent to the National Highway-47 passing through Thiruvananthapuram District which lies on the south-west coast of India, was carried out with a view to find out the air pollution tolerance as well as sensitivity of the plant species during different seasons. Among the trees in the roadside areas studied, Polyalthia longifolia, (Sonner) Thw., expressed highest APTI values and proved to be a tolerant variety and the others as sensitive species to air pollutants. In the case of shrubs, Clerodendron infortunatum, L., exhibited highest APTI values (7.34) and found to be more tolerant compared to the other two shrub species studied.     

Phytoremediation of petroleum-contaminated soils: Pre-screening for suitable plants and rhizospheral fungi

A field study was conducted in a petroleum-contaminated site in Kermanshah refinery (Iran) to find the petroleum-resistant plant species and the rhizospheral fungi for being used in bioremediation. Results showed that the amounts of petroleum pollution in non-vegetated areas is 6.8% and in vegetated areas is 2.2%. Plant samples were collected from petroleum-polluted areas and determined using morphological characters. It was found that eight plant species were growing on the contaminated sites: Polygonum aviculare, Amaranthus retroflexus, Noea mucronata, Alhaji cameleron, Crozophora heirosolymitrana, Poa sp., Convolvulus arvensis and Trifolium repense. The rhizospheral fungi of the plants were collected and determined using microscopic studies and taxonomical keys. The results determined the presence of 21 species in the rhizosphere of the plants growing in the polluted areas; three of these species were common in all of the plants and the others have species-specific distribution within the plants. The highest number of rhizospheral fungi (11 species) were determined for P. aviculare in non-polluted areas and nine species in polluted areas. It seems that the plant is the best candidate for using phytoremediation. However, the variation of fungi in petroleum-polluted areas was more than non-polluted zones. The culture of fungi in oil-contaminated media showed that, although all the studied fungi were resistant to low petroleum pollution (1% v/v), a few species, especially Fusarium species, showed higher resistance to petroleum pollution (10% v/v) and hence they may be suitable for mycoremediation in highly polluted areas.     

Bronchial contamination with toxic metals in mineral-based industrial areas of India

Selected toxic metals (Zn, Pb, Cu, Cr, Co, Cd, Ni and Mn) were determined by atomic absorption spectrophotometry in 55 samples of bronchial washouts obtained from patients with respiratory ailments. These subjects either worked or lived in industrial locations which have mineral-based industries such as steel plants, thermal power plants, cement plants, limestone mines and iron ore mines. Half of the samples analysed were from the plant workers and the other half from the non-workers living in the respective industrial areas. Samples from subjects living outside the industrial areas were also collected and analysed. The highest occurrence of toxic metals was found in the subjects living in the steel plant area. The occurrence was of the order: steel plant > thermal power plant > cement plant > iron ore mines > limestone mines > non industrial areas. Plant workers showed a higher presence of metals in their respiratory tracts compared to the non-workers in each industrial area. Higher depositions were noticed in areas of coal-fired industries compared to non-coal-fired industries. Zn, Cu and Pb were more likely to reach the respiratory tracts. The occurrences were found to increase with the age of the subjects. A slightly higher susceptibility to bronchial contamination was noticed in females.To whom correspondence should be addressed.     

Assessing human exposure to aluminium,chromium and vanadium through outdoor dust ingestion in the Bassin Minier de Provence,France

The Western part of the “Bassin Minier de Provence”, a former coal mining area, is still occupied by old polluting industries such as a coal-fired power plant and an alumina factory. The identified pollution sources that raise more concern in the population are the emission of gases and dusts, as well as the storage of raw and transformed materials. In 2011, a preliminary survey was carried out in the area as the first step to an exposure and health risk-assessment study. This first survey intends to assess human exposure through ingestion and health risk associated with potentially harmful elements (PHEs) in ground-level dusts collected in recreational areas used by children. Dust samples were taken at 19 sites distributed across the study area, depending on the location of public parks, public gardens, playgrounds and schools. Pseudo-total concentrations of 53 elements were determined by ICP-MS. Bioaccessible concentrations were estimated using the unified bioaccessibility method. This study presents the results obtained for Al, V and Cr, which seem to be related with industry and show similar distribution patterns. PHEs presumably related to traffic or other urban pollution sources are not discussed in this study. The highest total concentrations occur in dusts near the alumina plant that have significant amounts of Al mineral phases (gibbsite and alumina). However, in these dusts only small fractions of the elements under study are in bioaccessible forms. The highest bioaccessible fractions occur in dusts collected near the coal-fired power plant. Further investigation is required to assess potential pathways of exposure and health risk in this area.     

Impact of air pollution on floral morphology of Cassia siamea Lamk

Cassia siamea plants growing at two different sites (polluted and non-polluted) on two important roads of Agra city exhibited significant differences in their flowering phenology and floral morphology. The flowering in plants growing at polluted site is delayed and there was a marked reduction in flowering density, flowering period, size of floral parts, pollen fertility, fruit and seed-set. SEM observations revealed the presence of well developed glandular structures and reduction in the number and size of large stomata on the anther surface at polluted site. These changes were found to be closely associated with the extent of air pollution caused mainly by significant in the number of automobiles.     

Response of benthic foraminifera to heavy metal contamination in marine sediments (Sicilian coasts,Mediterranean Sea)

To examine the suitability of benthic foraminifera and their test deformations as bioindicators of pollution in coastal marine environments, we studied foraminifera and metal concentrations in 72 marine sediment samples, collected from the inner shelf along the Sicilian coast (Gulfs of Palermo and Termini) and on the south-eastern coast of Lampedusa Island. These areas are characterised by different environmental conditions. On the basis of pollution sources and foraminiferal assemblages, we recognised different zones in the Gulf of Palermo. The most polluted zones showed high metal concentrations, and low diversity of benthic foraminifera with species typical of stressed environments. By contrast, the lowest polluted zones showed a high population density and the highest percentages of epiphytes. Epiphytes were abundant where a Posidonia oceanica meadow was present and decreased in the most polluted zones. Sediments of the Gulf of Termini and Lampedusa exhibited high percentages of benthic foraminifera typical of well-oxygenated waters and low concentrations of metals, with the exception of sites located near sewage outfalls and harbour areas. Furthermore, even though deformed tests are commonly known in natural stressed environmental conditions, this study shows that in the most polluted zones, benthic foraminifera were characterised by the highest percentages of deformed individuals.     

Screening for plants and rhizospheral fungi with bioremediation potency of petroleum-polluted soils in a Tehran oil refinery area

The contamination of soils by toxic and/or hazardous organic pollutants, especially with crude oil, is a widespread problem. This study was conducted in a petroleum-contaminated area in a Tehran oil refinery to find petroleum-resistant plants and their rhizospheral fungal strains with bioremediation potency. The plants growing in the oil-polluted area were collected and determined taxonomically. Root samples of the plant species were collected from a polluted area and fungal strains determined by laboratory methods and taxonomical keys. The growth ability of the isolated fungal strains was studied in media containing 1%–15% crude oil. Results showed that seven plant species were of the highest density in the contaminated area: Alhagi persarum, Hordeum marinum, Peganum harmala, Phragmites australis, Prosopis farcta, Salsola kali, and Senecio glaucus. The root-associated fungi were isolated and showed that the fungal variation in the oil-polluted area is higher than that in a non-polluted area. The growth assay of isolated fungal strains showed that all studied fungal strains were able to form colonies at the applied concentrations but Alternaria sp. and Rhizopus sp. were the most resistant ones. Some plants were resistant to oil pollution, which also had positive effects on the fungal strains.     

平原河网地区大型底栖动物群落结构及其与环境因子的关系

大型底栖无脊椎动物是河流生态系统的重要组成生物,具有活动范围相对固定、生命周期较长、生活习性相对稳定等特点,可有效指示河流水质和水生态系统健康状况。有关大型底栖生物群落结构特征及其与水环境之间的关系研究一直是河流生态系统的研究热点。底栖动物具有较强的地域性,其群落结构特征受当地的自然环境特征和社会经济发展程度的双重因素影响。为研究典型平原河网地区的底栖动物群落结构及对水环境状况的响应特征,在上海市选取了83个河道断面进行大型底栖动物采样分析,共获取底栖动物20个分类单位（种）,其中软体动物10种,环节动物6种,节肢动物4种。上海河道底栖动物群落结构总体呈现结构单一、物种丰富度低、高度耐污性等显著特征,环节动物的栖息密度和出现频率均最高。城市化水平的空间差异性直接影响底栖动物空间分布的异质性,由市区至近郊、远郊,物种数从11种逐渐上升至15种,而栖息密度则由8 776.3个/m2下降至690.3个/m2。底栖动物群落结构的空间分布特征与水质理化指标的空间分布特征具有良好的对应性,水质空间变化导致环节动物和软体动物、节肢动物的空间分布存在一定交错性,耐污性较强的环节动物主要分布在有机污染重、溶解氧低的市区河道断面,而喜清洁环境的软体动物和节肢动物主要分布在水质较好的郊区断面。寡毛纲物种的栖息密度与溶解氧质量浓度呈显著负相关性。     

Impact of kraft pulp-mill effluents on estuarine and coastal fishes in Apalachee Bay,Florida, USA

A 2-year field study was carried out to determine the impact of kraft pulp-mill effluents on the fish fauna of a shallow-bay system in north Florida (Apalachee Bay, USA). Offshore areas that received kraft-mill effluents (KME) displayed significant increases in color and turbidity and reductions in (benthic) dissolved oxygen compared to a nearby control area. Estuarine and marsh fish assemblages in areas of acute impact were severely reduced in terms of numbers of individuals (N) and species (S). Offshore areas exposed to varying (chronic) levels of KME were characterized by complex interactions that included seasonal variations of impact. A broad offshore area showed reductions in numbers of individuals and species taken per month. However, the cumulative (annual) number of species taken was the same for polluted and unpolluted (control) areas due to a recruitment of relatively rare species in the areas of impact. Such polluted areas showed decreased dominance as well as qualitative differences in species composition compared to control areas. Inshore bay stations that were most severely affected by KME were dominated by the bay anchovy, Anchoa mitchilli. While species richness and species diversity were lower at the highly stressed stations, in other outlying areas of moderate impact (reduced N and S) there were no reductions of such parameters compared to control areas. Thus, species diversity was not an indicator of pollution per se, and was useful only when taken in conjunction with various other parameters. Transition areas (between polluted and unpolluted portions of the bay) showed substantial (although periodic) increases in N, S, and species diversity. Equitability indices were unchanged in polluted portions of the bay. In general, the effects of KME on offshore fish assemblages appeared to be due to a complex combination of habitat alteration, reduced benthic productivity, and individual behavioral reactions. The alterations of fish assemblages were compared to other studies in this area on benthic macrophytes and invertebrates in an effort to assess the usefulness of various indices in studies on the long-term effects of pollution on estuarine and coastal systems. It was found that kraft pulp-mill effluents had a pronounced effect on the benthic standing crop of plants and animals, but that intensive sampling over prolonged periods of time was necessary for an adequate assessment of the problem. Overall, there were some significant changes in the biota such as reduced dominance and productivity in polluted areas that were similar for the various types of organisms sampled.     

苔藓植物资源保护利用中的生态环境效应研究进展

苔藓植物资源丰富、种类繁多、分布广泛,是一类以孢子繁殖,由水生向陆生过渡的高等植物。苔藓植物的结构相对简单,对环境变化的反应较为敏感,被广泛应用为环境污染的指示植物。苔藓植物生长与所处的环境有关,而它的生长对土壤结皮形成、水土保持、生态小环境改善等方面又发挥着重要的促进作用。综述了苔藓植物的资源分布、苔藓植物对环境污染的响应、苔藓植物的生态效应等方面的研究进展,但是目前的研究领域及其研究角度还存在着各自的不足。随着经济建设快速发展,世界各地大量的矿山开采、水电开发等工程建设对土地、自然环境的破坏日益严重,非农业建设以及农产品需求不断增加造成了农田的生态结构与功能发生着不断变化。针对各地经济社会发展以及城乡建设现状,积极开展工程建设领域以及农田生态系统苔藓植物的生态环境效应研究是今后值得十分重视的研究方向。     

Aufnahme von 2,4,6-Trinitrotoluol in Pflanzen

Soil contaminations with the explosive 2,4,6-TNT are a major problem at many sites of former ammuniton plants in Germany. But only little is known about its environmental or metabolic fate in soil or plants. A field study was conducted on a former ammunition plant in Stadtallendorf/Hessen. Three areas with different TNT concentrations were planted with 8 different crops. After harvest plants were analyzed for TNT, ADNTs and DNTs. Soil contamination decreased in the rhizosphere compared to unplanted areas and there was a transfer of TNT from soil to the plants. Accumulation in plants was dependent on soil contamination and also specific for different plant parts or plant species. The contamination spectrum of TNT and derivatives was different in soil or plant tissue, respectively. After acid hydrolysis of bean roots, 2,6-DNT and 2,4-DNT could be identified in the extract.     

A comparative analysis of alien plant species along the Romanian Black Sea coastal area. The role of harbours

Previous studies have found a higher proportion of alien plant species along the coastal area of the Black Sea. The goals of the present study were to assess the role of two harbours as gateways and reservoirs for alien plant species, to compare the structure and invasion pattern of the alien plants recorded there, and test methods useful for effective monitoring programs. We inventoried 12 sites along the western Black Sea coast from the harbour of Sulina in the north to Cape Kaliakra in the south. Each site was visited at least three times each. A more intensive survey was done in the two harbours targeted by our study: Constanţa and Sulina. The proportion of neophytes was higher in the harbours (representing about one third of the total plant species) and lower in coastal protected areas (with an average proportion of 6.7%). Species accumulation curves and estimators of species richness indicated that while the plant inventory was not complete, invasive alien species (IAS) were adequately inventoried. Harbours act not only as gateways for IAS but also as reservoirs, facilitating their acclimatization and naturalization. The use of species accumulation curves and estimators of species richness are useful tools in designing and evaluating simple monitoring programs based on repeated inventories. Our study has stressed the importance of monitoring not only coastal waters but also green areas in harbours for the early detection of IAS.     

Effects of kraft-mill effluents on benthic macrophyte assemblages in a shallow-bay system (Apalachee Bay,North Florida,USA)

A 14-month study was carried out to determine the impact of kraft-mill effluents on the offshore benthic macrophyte distribution in a shallow north Florida Bay (USA). A polluted river drainage system was compared to an adjoining (unpolluted) one. The affected area was characterized by elevated levels of color and turbidity. Inshore areas associated with high levels of KME were characterized by severely reduced benthic macrophyte biomass, reduced numbers of species/unit area, and altered species composition when compared to control stations. Areas of chronic impact also had reduced levels of biomass, although the total number of species taken were not significantly different from the controls. In polluted areas, red and brown algae were proportionately more abundant than chlorophytes and spermatophytes. Dominance generally was reduced in areas of the Bay affected by KME. Except for areas of acute impact, there was no significant difference in species diversity (H) between polluted and unpolluted portions of the Bay. There were uniform increases in the total number of species on either side of the affected drainage system. Such areas were considered to be transition zones between the polluted and unpolluted parts of Apalachee Bay. Benthic macrophyte distribution, in terms of biomass and species (community) composition, was considered an important indicator of the impact of KME on the shallow coastal systems in question. The pattern of macrophyte species composition reflected various water-quality parameters. Species normally inhabiting deeper water were found in areas of increased turbidity and color. It was postulated that reduction of normal dominants such as Thalassia testudinum and Halimeda incrassata allowed the colonization of such areas by opportunistic species. This would explain the maintenance of comparable (total) numbers of species in polluted areas and the lack of effect of KME on species diversity even though biomass was severely restricted. These parameters were analogous to the epibenthic fish distribution in the respective drainage areas. Near-shore coastal systems in Apalachee Bay thus were affected by gradients in water quality in addition to natural (seasonal) fluctuations in key physical and chemical parameters. The benthic plant assemblages reflected variations in dominance, the occurrence of opportunistic species, and ecological diversity that resulted in a continuum of disturbance phenomena ranging from sparsely distributed groups in grossly polluted systems to well developed plant assemblages in areas that remain unaffected by KME.     

Effect of Vertebrate Grazing on Plant and Insect Community Structure

Abstract: We compared species diversity of plants and insects among grazed and ungrazed areas of Ponderosa pine–grassland communities in Arizona. Plant species richness was higher in two of three grassland communities that were grazed by native elk and deer and domestic cattle than in ungrazed areas inside a series of three large (approximately 40-ha) grazing exclosures. Similarly, plant species richness was higher in grazed areas relative to ungrazed areas at one of two series of smaller (approximately 25-m²) and short-term exclosure sites. Evenness of plant distribution, however, was greater inside ungrazed long-term exclosures but was reduced inside ungrazed short-term exclosures relative to grazed areas. Relative abundances of forbs, grasses, trees, and shrubs, and native and introduced plants did not differ between the long- and short-term grazing exclosures and their grazed counterparts. Relative abundances of some plant species changed when grazers were excluded, however. In contrast, insect species richness was not different between grazed and ungrazed habitats, although insect abundance increased 4- to 10-fold in ungrazed vegetation. Our results suggest that vertebrate grazing may increase plant richness, even in nutrient-poor, semi-arid grasslands, but may decrease insect abundances.     

Heavy metals,occurrence and toxicity for plants: a review

Metal contamination issues are becoming increasingly common in India and elsewhere, with many documented cases of metal toxicity in mining industries, foundries, smelters, coal-burning power plants and agriculture. Heavy metals, such as cadmium, copper, lead, chromium and mercury are major environmental pollutants, particularly in areas with high anthropogenic pressure. Heavy metal accumulation in soils is of concern in agricultural production due to the adverse effects on food safety and marketability, crop growth due to phytotoxicity, and environmental health of soil organisms. The influence of plants and their metabolic activities affects the geological and biological redistribution of heavy metals through pollution of the air, water and soil. This article details the range of heavy metals, their occurrence and toxicity for plants. Metal toxicity has high impact and relevance to plants and consequently it affects the ecosystem, where the plants form an integral component. Plants growing in metal-polluted sites exhibit altered metabolism, growth reduction, lower biomass production and metal accumulation. Various physiological and biochemical processes in plants are affected by metals. The contemporary investigations into toxicity and tolerance in metal-stressed plants are prompted by the growing metal pollution in the environment. A few metals, including copper, manganese, cobalt, zinc and chromium are, however, essential to plant metabolism in trace amounts. It is only when metals are present in bioavailable forms and at excessive levels, they have the potential to become toxic to plants. This review focuses mainly on zinc, cadmium, copper, mercury, chromium, lead, arsenic, cobalt, nickel, manganese and iron.     

Correlations between physiological responses of four aquatic plant species and river water quality

The Jiushanwai channel is located in the Lucheng district of Wenzhou City, China. Four aquatic plant species (Canna indica, Cyperus alternifolius, Myriophyllum verticillatum, and Lythrum salicaria) were planted on floating-beds constructed in a north-south layout along this channel. Five sites were sampled during spring, summer and autumn. The physiological characteristics (content of chlorophyll and soluble protein, activity of peroxidase and catalase) of the plants and the corresponding water quality were determined and correlations between these indices were analysed. The physiological indices of the plants and water quality changed regularly at the five sampling sites. Myriophyllum verticillatum was the most sensitive species to water quality changes, whereas Lythrum salicaria was least sensitive. Of the physiological indices examined, soluble protein content was most sensitive to water quality changes. The physiological indices of M. verticillatum are deemed to be most suitable to indicate river water quality.     

Phytoremediation potential of weed plants’ oxidative biomarker and antioxidant responses

The purpose of this study was to assess the oxidative biomarkers responses, antioxidant potential and metal accumulation tendency of weed plants collected from the control and metal-contaminated site. The metal contamination was found to be higher in soil and plant parts collected from contaminated site and the most serious problem seemed to be metal elevations above than the safe limit for Cd, Pb and Ni in the aerial parts of weed plants. There were variations in metal accumulation in different weed plants that was justified by principal component analysis. The enzymatic and non-enzymatic antioxidants were found to be higher in plant parts collected from contaminated site. Based upon metal accumulation tendency, weed plants showed a translocation ratio (>1) that reflect their potential for metal remediation. The values of metal pollution index also showed higher tendency of metal accumulation in weed plants, particularly in Solanum nigrum, Euphorbia hirta, Amaranthus hybridus and Xanthium strumarium, and they can also flourish at contaminated sites with more production of antioxidants. So, it suggests that studied weed species can be classified as phytoremediation plants and can be used as eco-friendly and economically feasible technique for restoring the land contaminated with toxic metals.     

Elemental Analysis of Water and Sediments by External Beam PIXE Part 2. Industrial Zone of Ptolemais, Greece

In the industrial zone of Ptolemais, Greece there are two coal-fired power plants, one nitrogen-fertilizer producing plant and a factory making coal-bricks. The industrial and the municipal waste effluents of this area are discharged into the lake Vegoritis via a small stream named Solou. Water and core or grab sediment samples taken from the Solou stream and Vegoritis Lake were analyzed for metallic elements by the proton induced X-ray emission (PIXE) method and the different pollution sources of the area under study, as far as metal pollution is concerned, were tentatively identified. The communities contribute to the pollution with loads of Pb and Ni; Ca, Cr, and Mo are contributed mainly by industries, while Fe, Zn, Mn, Sr, and Br have their origin to both sources. Also the sediment enrichment factors (SEF) are calculated and discussed.     

The impact of gasoline emission on plants – a review

This review presents the status of knowledge about gasoline exhaust pollution and its impact biochemical and physiological characteristics of plants. Parameters on such as leaf conductance, membrane permeability, ascorbic acid, chlorophyll and relative water content have been used as indicators to assess the impact of gasoline exhaust pollution on plant health. Tolerant plants such as Mangifera indica Linn. are reported showing an insignificant decrease in the percentage of chlorophyll content (3.6%) and a significant increase in the percentage of ascorbic acid (84.6%) and sensitive plants such as Cassia fistula are reported showing a significant decrease in the percentage of chlorophyll (66.4%) as well as ascorbic acid (32.9%). In the case of ornamental plants, Dracaena deremensis has been reported to show an insignificant decrease in the chlorophyll content but a significant increase in the ascorbic acid, pH and relative water content, which were found to be in tolerant category, while Dianthus caryophyllus showed sensitive characteristics. Such plants can be used as sinks and bioindicators for gasoline exhaust pollution. Though several studies reported biochemical impacts of individual or combined exhaust gases on plant species, the cumulative effect of gasoline exhaust on plant species has not been studied extensively, especially in the developing countries.     

Effect of Pollution On the Occurrence, Distribution and Sulphur Transformation Ability of the Thiobacilli in the River Ganga

The occurrence, distribution and nature of ambient thiobacilli along with their ability to oxidize different sulphur species under simulated natural and in vitro culture conditions were studied in the polluted and unpolluted sites of the River Ganga.

Thiobacillus thioparus, T. thiooxidans and T. denitrificans were isolated from the river water. the former two occurred in both polluted and unpolluted sites, while T. denitrificans occurred in polluted areas only. the paper pulp mill effluent discharge area contained the highest population of T. thioparus. the sewage drainage area showed relatively higher populations of T. thiooxidans and T. denitrificans.

The present study revealed that only biological oxidation of either thiosulphate or elemental sulphur occurred in the river water. All the thiobacilli screened oxidized thiosulphate, and three-fourths of them oxidized elemental sulphur. Some strains were found to be very good acidifiers. in spite of such acidification by the ambient thiobacilli, the pH of the river water remained alkaline. the specific rates of thiosulphate (0.18 -0.51 μMmolh^-1 mg^-1 cell) and sulphur (1.3 - 6.2 Normality day^-1 mg^-1 biomass) oxidations under simulated natural condition were found to be higher in polluted areas when compared with the unpolluted one (sulphur: 0.8 - 1.0 Normality day^-1 mg^-1).

Further, addition of thiouslphate or elemental sulphur in the river water in simulated in vitro condition resulted in the increase of respective oxidation rates. the variations in the natae of pollutants discharged into the river water influenced the oxidation rate of thiosulphate or sulphur.