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Plant regeneration potential in fly ash ecosystem
Urban Forestry & Urban Greening 15 (2016) 40–44
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Urban Forestry & Urban Greening journal homepage: www.elsevier.com/locate/ufug
Short communication
Plant regeneration potential in fly ash ecosystem Vimal Chandra Pandey a,∗ , Omesh Bajpai b , Nandita Singh a a b
Plant Ecology and Environmental Science Division, CSIR-National Botanical Research Institute, Lucknow 226001, India Department of Botany, Banaras Hindu University, Varanasi 221005, India
a r t i c l e
i n f o
Article history: Received 17 June 2015 Received in revised form 2 November 2015 Accepted 18 November 2015 Available online 22 November 2015 Keywords: Plantation Regeneration status Population density Fly ash ecosystem
a b s t r a c t Ability of certain plant species to regenerate by adaptive growth can address the harsh conditions of fly ash dumps in fly ash ecosystem. In the present study, we examined the status of regeneration potential of planted tree species in three life forms at fly ash ecosystem of tropical zone. On the basis of importance value index Prosopis juliflora (Sw.) DC., Pithecellobium dulce (Roxb.) Benth. and Pongamia pinnata (L.) Pierre have been found as dominant species in fly ash ecosystem. In this regeneration status study, the above three tree species (68.91%) have been found in good regeneration category which can be used for revegetation of new fly ash dumping sites. © 2015 Elsevier GmbH. All rights reserved.
1. Introduction Continuous increase in the number and area of fly ash (FA) dumpsites is a worldwide concern due to their potential toxic effects and heavy metals released in the environment (Pandey, 2015). The toxic elements i.e. As, Cd, Cr, Pb, Hg, etc. and polycyclic aromatic hydrocarbons (PAHs) are the potential pollutants of FA that can contaminate air, soil and water in the vicinity of coalbased thermal power plants (Pandey et al., 2011; Ribeiro et al., 2014; Verma et al., 2015). In this direction, mismanagement of FA dumps may contaminate the surrounding air, soil and water and could lead to pollution levels that can affect human health and their livelihood (Pandey et al., 2011; George et al., 2015). All the environmental problems of FA can be mitigated by revegetation of the ash dumpsites. For the successful restoration and revegetation of a FA landfill, an investigation of plant adaptability and their regeneration potential is needed in FA ecosystem. It is well known fact that natural plant colonization processes on FA dumps take place slowly due to unfavorable substrate and local conditions (Pandey and Singh, 2012). Thus, the plantation of suitable phytoremediating plants should be adopted to boost the plant colonization on these sites. Successful plantation on FA dumps is a tough job due to its physicochemical limitations regarding plant growth (Carlson and Adriano, 1993; Pandey et al., 2009a). However, revegetation is the best approach to eliminate the hazardous effects
∗ Corresponding author. Tel.: +91 9454287575. E-mail addresses: [email protected], [email protected] (V.C. Pandey). http://dx.doi.org/10.1016/j.ufug.2015.11.007 1618-8667/© 2015 Elsevier GmbH. All rights reserved.
of FA dumpsites (Haynes, 2009; Pandey et al., 2009a), which can be achieved through ecological engineering (Pandey and Singh, 2012, 2014; Pandey, 2015). Planting of grass, shrub, and woody species stops erosion and stabilizes toxic trace elements either by the plant uptake or the binding of ash particle by their roots, and ultimately creating the conditions towards soil formation (Ram et al., 2008; Juwarkar and Jambhulkar, 2008; Jambhulkar and Juwarkar, 2009; Pandey et al., 2012, 2015a). Most of the research work on FA as a soil ameliorant has been done in agriculture area (Lee et al., 2006; Ram et al., 2007; Pandey et al., 2009b, 2010; Singh et al., 2011; Singh and Pandey, 2013; Pandey and Kumar, 2013) as well as in reclamation of degraded lands (Pandey and Singh, 2010; Ram et al., 2006; Ram and Masto, 2010; Srivastava et al., 2014). Likewise, several researches have been carried out on phytoremediation, restoration and revegetation of FA dumpsites through potential plant species (Gupta and Sinha, 2008; Maiti and Jaiswal, 2008; Mitrovic et al., 2008; Ram et al., 2008; Pandey et al., 2012, 2014, 2015a,b; Kumari et al., 2013; Pandey, 2015). Some studies have also been conducted towards microbial remediation of FA hazards (Tewari et al., 2008; Rau et al., 2009; Babu and Reddy, 2011). Furthermore, Tropek and his colleagues have worked on FA dumps and showed interesting results about conservation potential of FA dumps for colonizing by some insects and arthropod groups (Tropek et al., 2013, 2014). To the best of our knowledge, there are no reports on the regeneration status of planted species in rehabilitated FA ecosystem. Therefore, the present study provides the information about the regeneration status of the planted tree species on FA dumps of Panki Thermal Power Station, Kanpur district of Uttar Pradesh, India. The aim of this study was to assess the regeneration potential of tree species
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Fig. 1. Lush growth of planted tree species on fly ash dumps of Panki Thermal Power Station, Kanpur District of Uttar Pradesh, India: (A) Landscape view of manmade plantation on fly ash dump; (B) biomass and carbon storage in fly ash ecosystem through plantation and carbon sequestration potential through root secretion and litter turnover (Inset); (C) Dense and fast growth of Prosopis juliflora towards high adaptability of fly ash dumps; (D) Multiple stem growth of Pithecellobium dulce on fly ash dumps, Photographs by V.C. Pandey.
for revegetation of FA dumps. Our hypothesis was that the planted Prosopis juliflora (Sw.) DC. on FA dumps has best adaptability than other planted species towards the sustainability of FA ecosystem. 2. Materials and methods 2.1. Study site description Coal based “Panki Thermal Power Station” is located at Panki in Kanpur district (26◦ 28 19 N 80◦ 14 1 E) of Uttar Pradesh, India. The ash dumped site is situated near Panki Thermal Power Station. The substrate under study here is FA dump, a heap of coal combustion residue of thermal power station. A thick (>10 cm) layer of soil was used to accelerate initial establishment and growth of plantation on the harsh conditions of FA dumps. The plantation was raised on old FA dumping site by the Panki Thermal Power Station. For this, six month old nursery raised saplings of different tree species were used for plantation during the beginning of monsoon. However, protective watering was done manually especially during summer months for the first year. This revegetated area was protected by a fence to check the hindrance of local animals and villagers. Now, this revegetated area of FA dump was converted into a FA ecosystem. At the time of assessing the regeneration status of the planted tree species, natural colonisation of Lantana camara L., Saccharum spontaneum L., Calotropis procera (Aiton) Dryand, Cannabis sativa L., Parthenium hysterophorus L. and Argemone Mexicana L. were also observed on outer side of FA ecosystem. The climate of this region is tropical with three distinct seasons viz., summer (April to June), monsoon (July to September) and winter (November to February). Temperature varies from 4.0 ◦ C to 46.0 ◦ C throughout the year. The average annual rainfall in Kanpur district is 875 mm.
2.2. Data collection The status of regeneration was assessed in the course of 2014–2015 for the tree plantation at FA dumping site of Panki Thermal Power Station, Kanpur. Three life forms were considered during the study (i.e. adult tree, sapling and seedling). Nested random quadrats were laid out to collect the required data; where 10 × 10, 5 × 5 and 1 × 1 m quadrates were used for adult trees, saplings and seedlings respectively. A sum of 27, 52 and 81 quadrates were laid down for adult trees, saplings and seedlings respectively. All three
Fig. 2. Density (%) of plants on fly ash dumping site of Panki thermal power station, Kanpur (AE, Ailanthus excelsa Roxb.; AL, Albizia lebbeck (L.) Benth.; AP, Albizia procera (Roxb.) Benth.; DS, Dalbergia sissoo Roxb. ex DC.; ET, Eucalyptus tereticornis Sm.; HI, Holoptelea integrifolia (Roxb.) Planch.; LL, Leucaena leucocephala (Lam.) de Wit.; PD, Pithecellobium dulce (Roxb.) Benth.; PP, Pongamia pinnata (L.) Pierre; PJ, Prosopis juliflora (Sw.) DC.; ZM, Ziziphus mauritiana Lamk.).
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Fig. 3. A schematic illustration shows an increasing order of regeneration and revegetation potential of tree species at fly ash dump, linking this knowledge in action on the ground by practitioners for sustainable environmental development in view of mitigating fly ash dust particles and toxic metals leaching.
life forms were classified on the basis of CBH (Circumference at breast height), adult trees ≥20, sapling 10–20 and seedling <10 cm following Bajpai et al. (2015) with some modification. 2.3. Data analyses Density (100 m−2 ) was also calculated for different life forms of the species (Curtis and McIntosh, 1950; Misra, 1968; Krebs, 1989). Four categories were used to understand the regeneration status of encountered species for all three life forms viz. 1. Good (seedlings > saplings > adult trees), 2. Fair (seedlings > < saplings < adult trees), 3. Poor (no seedlings with saplings > < / = adult trees) and 4. No regeneration (no seedlings and saplings) (Uma Shankar, 2001). 3. Results and discussion The vegetation study of any waste dumpsites is an important step to know plant cover, population density, relative abundance, frequency, etc. towards determining the potential plants for their better implementation in restoration of new waste dumps (Pandey et al., 2015b). The luxuriant growth of planted tree species on FA dumps of Panki Thermal Power Station, Kanpur District of Uttar Pradesh, India which indicates huge biomass and carbon storage in FA ecosystem through plantation and carbon sequestration potential through root secretion and litter turnover (Fig. 1). Several studies on the assessment of plantation of FA dumps in term of tree survival and growth, photosynthetic efficiency, damage symptoms, metal accumulation capacity, phytostabilization potential have been done by researchers (Jambhulkar and Juwarkar, 2009; Pietrzykowski et al., 2010; Kostic et al., 2012; Krzaklewski et al., 2012; Mitrovic´ et al., 2012). But here the present study was undertaken to assess the potential plant species with their regeneration capacity on FA ecosystem. In this study, the overall average density was 0.81, 33.78 and 115.04 100 m−2 for adult trees, saplings and
seedlings, respectively. Thus, the plantation of the fly ash dumping site of Panki Thermal Power Station, Kanpur found under ‘Good’ regeneration status (Table 1). This good regeneration status of the area indicates that the plantation is moving towards the sustainability. Density and regeneration status of all the plant species vary distinctly may be due to their population structure and capability of growth and fecund on the FA dumping sites (Guedje et al., 2003). Prosopis juliflora (Sw.) DC. reported the highest density (2.59, 204.76 and 378.57) fallowed by Pithecellobium dulce (Roxb.) Benth. (1.89, 37.85 and 241.82) and Pongamia pinnata (L.) Pierre (0.96, 26.48 and 157.94) in all the three life forms (adult trees, saplings and seedlings), respectively. These three covered 68.91% of the total density and showed good regeneration status (Fig. 2). The higher seedling and sapling density of these species clearly indicates their higher germination and survival potential even on degraded and less nutritious soil. Their better capability for seed germination and seedling, sapling viability has already been reported from various part of the world on different harsh environmental conditions and soil types (Zimmerman, 1991; Brewbaker, 1992; Castro, 2000; Rai et al., 2004; El-Keblawy and Al-Rawai, 2005; Handa et al., 2005; Scott et al., 2008; Sujatha et al., 2008; Felker, 2009). Due to the good regeneration status and higher density in these three species, it has also been predicted that they become more dominant on the study site in near future. An increasing order of regeneration and revegetation potential of above three tree species at FA dump is presented here (Fig. 3), linking this knowledge in action on the ground by practitioners for sustainable revegetation of abandoned FA dumps, should be used for mitigating FA dust particles and leaching of toxic metals through plantation of dominant species. The highest density of P. juliflora also supports our hypothesis that the species has best adaptability to grow as well as to regenerate on FA dumpsites. Furthermore, the plants that have perennial nature, extensive root system, vegetative multiplication ability, nitrogen-fixing ability, tolerance to high pH, salinity and toxic metals, tolerance to high temperature and drought are the most suitable for
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Table 1 Density of different life forms (100 m−2 ) and regeneration status of tree species on fly ash dumping site of Panki thermal power station, Kanpur. S.No.
1 2 3 4 5 6 7 8 9 10 11
Plant name
Ailanthus excelsa Roxb. Albizia lebbeck (L.) Benth. Albizia procera (Roxb.) Benth. Dalbergia sissoo Roxb. ex DC. Eucalyptus tereticornis Sm. Holoptelea integrifolia (Roxb.) Planch. Leucaena leucocephala (Lam.) de Wit. Pithecellobium dulce (Roxb.) Benth. Pongamia pinnata (L.) Pierre Prosopis juliflora (Sw.) DC. Ziziphus mauritiana Lamk.
Family
Simaroubaceae Fabaceae Fabaceae Fabaceae Myrtaceae Ulmaceae Fabaceae Fabaceae Fabaceae Fabaceae Rhamnaceae Average
planting on FA deposits (Pandey et al., 2009a, 2015b; Pandey and Singh, 2011). Being nitrogen-fixing species, the planting of P. juliflora on FA dumps is of great importance for providing a suitable substrate for the next generation of commercial species in view of revenue generation. Most importantly, P. juliflora has both rhizobium and mycorrhizal associations that fixes more nitrogen amounts compared to those lacking the mycorrhiza (Orwa et al., 2009). These results may add to determine the adaptive potential of other tree species which have the capability to revegetate new FA dumping sites. It could be important for linking phytoremediation research and its extension on the ground by practitioners for ecological restoration of FA dumps. 4. Conclusions Based on the present findings, it can be concluded that the manmade plantation on FA dump creates a good ecosystem towards sustainability. Due to increasing release of pollutants from coalbased thermal power stations, like suspended particulate matter, toxic elements, significant amount of CO2 generation etc., we should improve our understanding for planting trees on FA dumps to protect our precious environment in which we live. In this direction, the present field results may be used as a significant tool to develop green cover on new FA dumpsites through plantation and upgrading phytomanagement policies of FA dumpsite. 5. Conflict of interest statement The authors declare no conflict of interest. Acknowledgements Financial support given to first author by Science and Engineering Research Board (No. SR/FTP/ES-96/2012), Govt. of India is gratefully acknowledged. The authors would like to thank the Panki Thermal Power Station for access to the plantation site of fly ash dumps. Authors are also thankful to Director, CSIR-National Botanical Research Institute, Lucknow for his kind support. References Babu, A.G., Reddy, M.S., 2011. Diversity of arbuscular mycorrhizal fungi associated with plants growing in fly ash pond and their potential role in ecological restoration. Curr. Microbiol. 63, 273–280. Bajpai, O., Kushwaha, A.K., Srivastava, A.K., Pandey, J., Chaudhary, L.B., 2015. Phytosociological status of a monotypic genus Indopiptadenia: a near threatened tree from the Terai–Bhabar Region of Central Himalaya. Res. J. For. 9 (2), 35–47. Brewbaker, J.L., 1992. Pithecellobium dulce—sweet and thorny. NFT Highlights 92, 2. Carlson, C.L., Adriano, D.C., 1993. Environmental impacts of coal combustion residues. J. Environ. Qual. 22, 227–247.
Density (100 m−2 )
Regeneration status
Tree
Sapling
Seedling
0.59 0.07 0.37 0.52 0.59 0.48 0.30 1.89 0.96 2.59 0.59 0.81
17.75 Nil 0.31 0.47 Nil 0.34 0.22 37.85 26.48 204.76 15.87 33.78
Nil Nil 0.24 8.75 Nil 10.45 7.54 241.82 157.94 378.57 Nil 115.04
Poor No regeneration Fair Fair No regeneration Fair Fair Good Good Good Poor Good
Castro, K.L., 2000. Estudios de germinación en Jaúly Cenízaro. Boletín-Mejoramiento Genéticoy Semillas Forestales 24, 1–5. Curtis, J.T., McIntosh, R.P., 1950. The interrelations of certain analytic and synthetic phytosociological characters. Ecology 31 (3), 434–455. El-Keblawy, A., Al-Rawai, A., 2005. Effects of salinity, temperature and light on germination of invasive Prosopis juliflora (Sw.) D.C. J. Arid Environ. 61, 555–565. Felker, P., 2009. Unusual physiological properties of the arid adapted tree legume Prosopis and their applications in developing countries. In: De La Barrera, E., Smith, W.K. (Eds.), Perspectives in Biophysical Plant Ecophysiology: A Tribute to Park S. Nobel. Universidad Nacional Autonoma de Mexico, pp. 221–255. George, J., Masto, R.E., Ram, L.C., Das, T.B., Rout, T.K., Mohan, M., 2015. Human exposure risks for metals in soil near a coal-fired power-generating plant. Arch. Environ. Contam. Toxicol. 68, 451–461. Guedje, N.M., Lejoly, J., Nkongmeneck, B.A., Jonkers, W.B.J., 2003. Population dynamics of Garcinia lucida (Clusiaceae) in Cameroonian Atlantic forests. For. Ecol. Manage. 177, 231–241. Gupta, A.K., Sinha, S., 2008. Decontamination and/or revegetation of fly ash dykes through naturally growing plants. J. Hazard. Mater. 153, 1078–1087. Handa, A.K., Nandini, D., Uma, 2005. An alternative source of biofuel, seed germination trials of Pongamia pinnata. Int. J. Usufructs Manage. 6, 75–80. Haynes, R.J., 2009. Reclamation and revegetation of fly ash disposal sites—challenges and research needs. J. Environ. Manage. 90, 43–53. Jambhulkar, H.P., Juwarkar, A.A., 2009. Assessment of bioaccumulation of heavy metals by different plant species grown on flyash dump. Ecotoxicol. Environ. Saf. 72, 1122–1128. Juwarkar, A.A., Jambhulkar, H.P., 2008. Restoration of fly ash dump through biological interventions. Environ. Monit. Assess. 139, 355–365. Kostic, O., Mitrovic, M., Kneˇzevic, M., Jaric, S., Gajic, G., Djurdj, L., Evic Pavlovic, P., 2012. The potential of four woody species for the revegetation of fly ash deposits from the ‘Nikola Tesla-A’ thermoelectric plant (Obrenovac Serbia). Arch. Biol. Sci. 64 (1), 145–158. Krebs, C.J., 1989. Ecological methodology. Harper and Row Publication, New York, NY. Krzaklewski, W., Pietrzykowski, M., Wos, B., 2012. Survival and growth of alders (Alnus glutinosa (L.) Gaertn. and Alnus incana (L.) Moench) on fly ash technosols at different substrate improvement. Ecol. Eng. 49, 35–40. Kumari, A., Pandey, V.C., Rai, U.N., 2013. Feasibility of fern Thelypteris dentata for revegetation of coal fly ash landfills. J. Geochem. Explor. 128, 147–152. Lee, H., Ha, H.S., Lee, C.H., Lee, Y.B., Kim, P.J., 2006. Fly-ash effect on improving soil properties and rice productivity in Korean paddy soils. Bioresour. Technol. 97, 1490–1497. Maiti, S.K., Jaiswal, S., 2008. Bioaccumulation and translocation of metals in the nat-ural vegetation growing on fly ash lagoons: a field study from Santaldih thermal power plant, West Bengal, India. Environ. Monit. Assess. 136, 355–370. Misra, R., 1968. Ecology Work Book. Oxford and IBH Publishing Company, New Delhi. ´ M., Jaric, ´ S., Kostic, ´ O., Gajic, ´ G., Karadˇzic, ´ B., Lola Djurdjevic, ´ L., Oberan, L., Mitrovic, ´ M., Pavlovic, ´ P., 2012. Photosynthetic efficiency of four ´ D., Pavlovic, Pavlovic, woody species growing on fly ash deposits of a Serbian ‘Nicola Tesla-A’ Thermoeclectric Plant. Pol. J. Environ. Stud. 21 (5), 1339–1347. Mitrovic, M., Pavlovic, P., Lakusic, D., Djurdjevic, L., Stevanovic, B., Kostic, O., Gajic, G., 2008. The potential of Festuca rubra and Calamagrostis epigejos for the revegetation of fly ash deposits. Sci. Total Environ. 407, 338–347. Orwa, C., Mutua, A., Kindt, R., Jamnadass, R., Anthony, S., 2009. Agroforestree Database: A Tree Reference and Selection Guide Version 4.0. World Agroforestry Centre, Kenya. Pandey, V.C., 2015. Assisted phytoremediation of fly ash dumps through naturally colonized plants. Ecol. Eng. 82, 1–5. Pandey, V.C., Abhilash, P.C., Singh, N., 2009a. The Indian perspective of utilizing fly ash in phytoremediation, phytomanagement and biomass production. J. Environ. Manage. 90, 2943–2958. Pandey, V.C., Abhilash, P.C., Upadhyay, R.N., Tewari, D.D., 2009b. Application of fly ash on the growth performance, translocation of toxic heavy metals within
44
V.C. Pandey et al. / Urban Forestry & Urban Greening 15 (2016) 40–44
Cajanus cajan L.: implication for safe utilization of fly ash for agricultural production. J. Hazard. Mater. 166, 255–259. Pandey, V.C., Bajpai, O., Pandey, D.N., Singh, N., 2015a. Saccharum spontaneum: an underutilized tall grass for revegetation and restoration programs. Genet. Resour. Crop Evol. 62 (3), 443–450. Pandey, V.C., Kumar, A., 2013. Leucaena leucocephala: an underutilized plant for pulp and paper production. Genet. Resour. Crop Evol. 60, 1165–1171. Pandey, V.C., Prakash, P., Bajpai, O., Kumar, A., Singh, N., 2015b. Phytodiversity on fly ash deposits: evaluation of naturally colonized species for sustainable phytorestoration. Environ. Sci. Pollut. Res. 22, 2776–2787. Pandey, V.C., Singh, B., 2012. Rehabilitation of coal fly ash basins: current need to use ecological engineering. Ecol. Eng. 49, 190–192. Pandey, V.C., Singh, J.S., Kumar, A., Tewari, D.D., 2010. Accumulation of heavy metal by chickpea grown in fly ash treated soil: effect on antioxidants. Clean—Soil Air Water 38, 1116–1123. Pandey, V.C., Singh, J.S., Singh, R.P., Singh, N., Yunus, M., 2011. Arsenic hazards in coal fly ash and its fate in Indian scenario. Resour. Conserv. Recycl. 55, 819–835. Pandey, V.C., Singh, K., 2011. Is Vigna radiata suitable for the revegetation of fly ash landfills? Ecol. Eng. 37, 2105–2106. Pandey, V.C., Singh, K., Singh, R.P., Singh, B., 2012. Naturally growing Saccharum munja on the fly ash lagoons: a potential ecological engineer for the revegetation and stabilization. Ecol. Eng. 40, 95–99. Pandey, V.C., Singh, N., 2010. Impact of fly ash incorporation in soil systems. Agric. Ecosyst. Environ. 136, 16–27. Pandey, V.C., Singh, N., 2014. Fast green capping on coal fly ash basins through ecological engineering. Ecol. Eng. 73, 671–675. Pandey, V.C., Singh, N., Singh, R.P., Singh, D.P., 2014. Rhizoremediation potential of spontaneously grown Typha latifolia on fly ash basins: study from the field. Ecol. Eng. 71, 722–727. Pietrzykowski, M., Krzaklewski, W., Gaik, G., 2010. Assessment of forest growth with plantings dominated by Scots pine (Pinus sylvestris L.) on experimental plots on a fly ash disposal site at the Bełchatow power plant. Environ. Eng. 137 (17), 65–74 (In Polish, English summary). Rai, U.N., Pandey, K., Sinha, S., Singh, A., Saxena, R., Gupta, D.K., 2004. Revegetating fly ash landfills with Prosopis juliflora L.: impact of different amendment and Rhizobium inoculation. Environ. Int. 30 (3), 293–300. Ram, L.C., Jha, S.K., Tripathi, R.C., Masto, R.E., Selvi, V.A., 2008. Remediation of fly ash landfills through plantation. Biorem. J. 18, 71–90. Ram, L.C., Masto, R.E., 2010. An appraisal of the potential use of fly ash for reclaiming coal mine spoil. J. Environ. Manage. 91, 603–617. Ram, L.C., Srivastava, N.K., Jha, S.K., Sinha, A.K., Masto, R.E., Selvi, V.A., 2007. Management of lignite fly ash through its bulk use via biological amendments for improving the fertility and crop productivity of soil. Environ. Manage. 40, 438–452.
Ram, L.C., Srivastava, N.K., Tripathi, R.C., Jha, S.K., Sinha, A.K., Singh, G., Manoharan, V., 2006. Management of mine spoil for crop productivity with lignite fly ash and biological amendments. J. Environ. Manage. 79, 173–187. Rau, N., Mishra, V., Sharma, M., Das, M.K., Ahaluwalia, K., Sharma, R.S., 2009. Evaluation of functional diversity in rhizobacterial taxa of a wild grass (Saccharum ravennae) colonizing abandoned fly ash dumps in Delhi urban ecosystem. Soil Biol. Biochem. 41, 813–821. Ribeiro, J., Silva, T.F., Mendonc¸a Filho, J.G., Flores, D., 2014. Fly ash from coal combustion—an environmental source of organic compounds. Appl. Geochem. 44, 103–110. Scott, P.T., Pregelj, L., Chen, N., Hadler, J.S., Djordjevic, M.A., Gresshoff, P.M., 2008. Pongamia pinnata: an untapped resource for the biofuels industry of the future. Bioenergy Res. 1, 2–11. Singh, J.S., Pandey, V.C., 2013. Fly ash application in nutrient poor agriculture soils: impact on methanotrophs population dynamics and paddy yields. Ecotoxicol. Environ. Saf. 89, 43–51. Singh, J.S., Pandey, V.C., Singh, D.P., 2011. Coal fly ash and farmyard manure amendments in dry-land paddy agriculture field: effect on N-dynamics and paddy productivity. Appl. Soil Ecol. 47, 133–140. Srivastava, N.K., Ram, L.C., Masto, R.E., 2014. Reclamation of overburden and lowland in coal mining area with fly ash and selective plantation: a sustainable ecological approach. Ecol. Eng. 71, 479–489. Sujatha, K., Panda, B.M., Hazra, S., 2008. De novo organogenesis and plant regeneration in Pongamia pinnata, oil producing tree legume. Trees 22, 711–716. Tiwari, S., Kumari, B., Singh, S.N., 2008. Evaluation of metal mobility/immobility in fly ash induced by bacterial strains isolated from the rhizospheric zone of Typha latifolia growing on fly ash dumps. Bioresour. Technol. 99, 1305–1310. Tropek, R., Cerna, I., Straka, J., Cizek, O., Konvicka, M., 2013. Is coal combustion the last chance for vanishing insects of inland drift sand dunes in Europe? Biol. Conserv. 162, 60–64. Tropek, R., Cerna, I., Straka, J., Kadlec, T., Pech, P., Tichanek, F., Sebek, P., 2014. Restoration management of fly ash deposits crucially influence their conservation potential for terrestrial arthropods. Ecol. Eng. 73, 45–52. Uma Shankar, 2001. A case of high tree diversity in a Sal (Shorea robusta)—dominated low land forest of eastern Himalaya: floristic composition, regeneration and conservation. Current Science 81, 776–786. Verma, S.K., Masto, R.E., Gautam, S., Choudhury, D.P., Ram, L.C., Maiti, S.K., Maity, S., 2015. Investigations on PAHs and trace elements in coal and its combustion residues from a power plant. Fuel 162, 138–147. Zimmerman, H.G., 1991. Biological control of mesquite, Prosopis spp. (Fabaceae), in South Africa. Agric., Ecosyst. Environ. 37, 175–186.
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Urban Forestry & Urban Greening journal homepage: www.elsevier.com/locate/ufug
Short communication
Plant regeneration potential in fly ash ecosystem Vimal Chandra Pandey a,∗ , Omesh Bajpai b , Nandita Singh a a b
Plant Ecology and Environmental Science Division, CSIR-National Botanical Research Institute, Lucknow 226001, India Department of Botany, Banaras Hindu University, Varanasi 221005, India
a r t i c l e
i n f o
Article history: Received 17 June 2015 Received in revised form 2 November 2015 Accepted 18 November 2015 Available online 22 November 2015 Keywords: Plantation Regeneration status Population density Fly ash ecosystem
a b s t r a c t Ability of certain plant species to regenerate by adaptive growth can address the harsh conditions of fly ash dumps in fly ash ecosystem. In the present study, we examined the status of regeneration potential of planted tree species in three life forms at fly ash ecosystem of tropical zone. On the basis of importance value index Prosopis juliflora (Sw.) DC., Pithecellobium dulce (Roxb.) Benth. and Pongamia pinnata (L.) Pierre have been found as dominant species in fly ash ecosystem. In this regeneration status study, the above three tree species (68.91%) have been found in good regeneration category which can be used for revegetation of new fly ash dumping sites. © 2015 Elsevier GmbH. All rights reserved.
1. Introduction Continuous increase in the number and area of fly ash (FA) dumpsites is a worldwide concern due to their potential toxic effects and heavy metals released in the environment (Pandey, 2015). The toxic elements i.e. As, Cd, Cr, Pb, Hg, etc. and polycyclic aromatic hydrocarbons (PAHs) are the potential pollutants of FA that can contaminate air, soil and water in the vicinity of coalbased thermal power plants (Pandey et al., 2011; Ribeiro et al., 2014; Verma et al., 2015). In this direction, mismanagement of FA dumps may contaminate the surrounding air, soil and water and could lead to pollution levels that can affect human health and their livelihood (Pandey et al., 2011; George et al., 2015). All the environmental problems of FA can be mitigated by revegetation of the ash dumpsites. For the successful restoration and revegetation of a FA landfill, an investigation of plant adaptability and their regeneration potential is needed in FA ecosystem. It is well known fact that natural plant colonization processes on FA dumps take place slowly due to unfavorable substrate and local conditions (Pandey and Singh, 2012). Thus, the plantation of suitable phytoremediating plants should be adopted to boost the plant colonization on these sites. Successful plantation on FA dumps is a tough job due to its physicochemical limitations regarding plant growth (Carlson and Adriano, 1993; Pandey et al., 2009a). However, revegetation is the best approach to eliminate the hazardous effects
∗ Corresponding author. Tel.: +91 9454287575. E-mail addresses: [email protected], [email protected] (V.C. Pandey). http://dx.doi.org/10.1016/j.ufug.2015.11.007 1618-8667/© 2015 Elsevier GmbH. All rights reserved.
of FA dumpsites (Haynes, 2009; Pandey et al., 2009a), which can be achieved through ecological engineering (Pandey and Singh, 2012, 2014; Pandey, 2015). Planting of grass, shrub, and woody species stops erosion and stabilizes toxic trace elements either by the plant uptake or the binding of ash particle by their roots, and ultimately creating the conditions towards soil formation (Ram et al., 2008; Juwarkar and Jambhulkar, 2008; Jambhulkar and Juwarkar, 2009; Pandey et al., 2012, 2015a). Most of the research work on FA as a soil ameliorant has been done in agriculture area (Lee et al., 2006; Ram et al., 2007; Pandey et al., 2009b, 2010; Singh et al., 2011; Singh and Pandey, 2013; Pandey and Kumar, 2013) as well as in reclamation of degraded lands (Pandey and Singh, 2010; Ram et al., 2006; Ram and Masto, 2010; Srivastava et al., 2014). Likewise, several researches have been carried out on phytoremediation, restoration and revegetation of FA dumpsites through potential plant species (Gupta and Sinha, 2008; Maiti and Jaiswal, 2008; Mitrovic et al., 2008; Ram et al., 2008; Pandey et al., 2012, 2014, 2015a,b; Kumari et al., 2013; Pandey, 2015). Some studies have also been conducted towards microbial remediation of FA hazards (Tewari et al., 2008; Rau et al., 2009; Babu and Reddy, 2011). Furthermore, Tropek and his colleagues have worked on FA dumps and showed interesting results about conservation potential of FA dumps for colonizing by some insects and arthropod groups (Tropek et al., 2013, 2014). To the best of our knowledge, there are no reports on the regeneration status of planted species in rehabilitated FA ecosystem. Therefore, the present study provides the information about the regeneration status of the planted tree species on FA dumps of Panki Thermal Power Station, Kanpur district of Uttar Pradesh, India. The aim of this study was to assess the regeneration potential of tree species
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Fig. 1. Lush growth of planted tree species on fly ash dumps of Panki Thermal Power Station, Kanpur District of Uttar Pradesh, India: (A) Landscape view of manmade plantation on fly ash dump; (B) biomass and carbon storage in fly ash ecosystem through plantation and carbon sequestration potential through root secretion and litter turnover (Inset); (C) Dense and fast growth of Prosopis juliflora towards high adaptability of fly ash dumps; (D) Multiple stem growth of Pithecellobium dulce on fly ash dumps, Photographs by V.C. Pandey.
for revegetation of FA dumps. Our hypothesis was that the planted Prosopis juliflora (Sw.) DC. on FA dumps has best adaptability than other planted species towards the sustainability of FA ecosystem. 2. Materials and methods 2.1. Study site description Coal based “Panki Thermal Power Station” is located at Panki in Kanpur district (26◦ 28 19 N 80◦ 14 1 E) of Uttar Pradesh, India. The ash dumped site is situated near Panki Thermal Power Station. The substrate under study here is FA dump, a heap of coal combustion residue of thermal power station. A thick (>10 cm) layer of soil was used to accelerate initial establishment and growth of plantation on the harsh conditions of FA dumps. The plantation was raised on old FA dumping site by the Panki Thermal Power Station. For this, six month old nursery raised saplings of different tree species were used for plantation during the beginning of monsoon. However, protective watering was done manually especially during summer months for the first year. This revegetated area was protected by a fence to check the hindrance of local animals and villagers. Now, this revegetated area of FA dump was converted into a FA ecosystem. At the time of assessing the regeneration status of the planted tree species, natural colonisation of Lantana camara L., Saccharum spontaneum L., Calotropis procera (Aiton) Dryand, Cannabis sativa L., Parthenium hysterophorus L. and Argemone Mexicana L. were also observed on outer side of FA ecosystem. The climate of this region is tropical with three distinct seasons viz., summer (April to June), monsoon (July to September) and winter (November to February). Temperature varies from 4.0 ◦ C to 46.0 ◦ C throughout the year. The average annual rainfall in Kanpur district is 875 mm.
2.2. Data collection The status of regeneration was assessed in the course of 2014–2015 for the tree plantation at FA dumping site of Panki Thermal Power Station, Kanpur. Three life forms were considered during the study (i.e. adult tree, sapling and seedling). Nested random quadrats were laid out to collect the required data; where 10 × 10, 5 × 5 and 1 × 1 m quadrates were used for adult trees, saplings and seedlings respectively. A sum of 27, 52 and 81 quadrates were laid down for adult trees, saplings and seedlings respectively. All three
Fig. 2. Density (%) of plants on fly ash dumping site of Panki thermal power station, Kanpur (AE, Ailanthus excelsa Roxb.; AL, Albizia lebbeck (L.) Benth.; AP, Albizia procera (Roxb.) Benth.; DS, Dalbergia sissoo Roxb. ex DC.; ET, Eucalyptus tereticornis Sm.; HI, Holoptelea integrifolia (Roxb.) Planch.; LL, Leucaena leucocephala (Lam.) de Wit.; PD, Pithecellobium dulce (Roxb.) Benth.; PP, Pongamia pinnata (L.) Pierre; PJ, Prosopis juliflora (Sw.) DC.; ZM, Ziziphus mauritiana Lamk.).
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Fig. 3. A schematic illustration shows an increasing order of regeneration and revegetation potential of tree species at fly ash dump, linking this knowledge in action on the ground by practitioners for sustainable environmental development in view of mitigating fly ash dust particles and toxic metals leaching.
life forms were classified on the basis of CBH (Circumference at breast height), adult trees ≥20, sapling 10–20 and seedling <10 cm following Bajpai et al. (2015) with some modification. 2.3. Data analyses Density (100 m−2 ) was also calculated for different life forms of the species (Curtis and McIntosh, 1950; Misra, 1968; Krebs, 1989). Four categories were used to understand the regeneration status of encountered species for all three life forms viz. 1. Good (seedlings > saplings > adult trees), 2. Fair (seedlings > < saplings < adult trees), 3. Poor (no seedlings with saplings > < / = adult trees) and 4. No regeneration (no seedlings and saplings) (Uma Shankar, 2001). 3. Results and discussion The vegetation study of any waste dumpsites is an important step to know plant cover, population density, relative abundance, frequency, etc. towards determining the potential plants for their better implementation in restoration of new waste dumps (Pandey et al., 2015b). The luxuriant growth of planted tree species on FA dumps of Panki Thermal Power Station, Kanpur District of Uttar Pradesh, India which indicates huge biomass and carbon storage in FA ecosystem through plantation and carbon sequestration potential through root secretion and litter turnover (Fig. 1). Several studies on the assessment of plantation of FA dumps in term of tree survival and growth, photosynthetic efficiency, damage symptoms, metal accumulation capacity, phytostabilization potential have been done by researchers (Jambhulkar and Juwarkar, 2009; Pietrzykowski et al., 2010; Kostic et al., 2012; Krzaklewski et al., 2012; Mitrovic´ et al., 2012). But here the present study was undertaken to assess the potential plant species with their regeneration capacity on FA ecosystem. In this study, the overall average density was 0.81, 33.78 and 115.04 100 m−2 for adult trees, saplings and
seedlings, respectively. Thus, the plantation of the fly ash dumping site of Panki Thermal Power Station, Kanpur found under ‘Good’ regeneration status (Table 1). This good regeneration status of the area indicates that the plantation is moving towards the sustainability. Density and regeneration status of all the plant species vary distinctly may be due to their population structure and capability of growth and fecund on the FA dumping sites (Guedje et al., 2003). Prosopis juliflora (Sw.) DC. reported the highest density (2.59, 204.76 and 378.57) fallowed by Pithecellobium dulce (Roxb.) Benth. (1.89, 37.85 and 241.82) and Pongamia pinnata (L.) Pierre (0.96, 26.48 and 157.94) in all the three life forms (adult trees, saplings and seedlings), respectively. These three covered 68.91% of the total density and showed good regeneration status (Fig. 2). The higher seedling and sapling density of these species clearly indicates their higher germination and survival potential even on degraded and less nutritious soil. Their better capability for seed germination and seedling, sapling viability has already been reported from various part of the world on different harsh environmental conditions and soil types (Zimmerman, 1991; Brewbaker, 1992; Castro, 2000; Rai et al., 2004; El-Keblawy and Al-Rawai, 2005; Handa et al., 2005; Scott et al., 2008; Sujatha et al., 2008; Felker, 2009). Due to the good regeneration status and higher density in these three species, it has also been predicted that they become more dominant on the study site in near future. An increasing order of regeneration and revegetation potential of above three tree species at FA dump is presented here (Fig. 3), linking this knowledge in action on the ground by practitioners for sustainable revegetation of abandoned FA dumps, should be used for mitigating FA dust particles and leaching of toxic metals through plantation of dominant species. The highest density of P. juliflora also supports our hypothesis that the species has best adaptability to grow as well as to regenerate on FA dumpsites. Furthermore, the plants that have perennial nature, extensive root system, vegetative multiplication ability, nitrogen-fixing ability, tolerance to high pH, salinity and toxic metals, tolerance to high temperature and drought are the most suitable for
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Table 1 Density of different life forms (100 m−2 ) and regeneration status of tree species on fly ash dumping site of Panki thermal power station, Kanpur. S.No.
1 2 3 4 5 6 7 8 9 10 11
Plant name
Ailanthus excelsa Roxb. Albizia lebbeck (L.) Benth. Albizia procera (Roxb.) Benth. Dalbergia sissoo Roxb. ex DC. Eucalyptus tereticornis Sm. Holoptelea integrifolia (Roxb.) Planch. Leucaena leucocephala (Lam.) de Wit. Pithecellobium dulce (Roxb.) Benth. Pongamia pinnata (L.) Pierre Prosopis juliflora (Sw.) DC. Ziziphus mauritiana Lamk.
Family
Simaroubaceae Fabaceae Fabaceae Fabaceae Myrtaceae Ulmaceae Fabaceae Fabaceae Fabaceae Fabaceae Rhamnaceae Average
planting on FA deposits (Pandey et al., 2009a, 2015b; Pandey and Singh, 2011). Being nitrogen-fixing species, the planting of P. juliflora on FA dumps is of great importance for providing a suitable substrate for the next generation of commercial species in view of revenue generation. Most importantly, P. juliflora has both rhizobium and mycorrhizal associations that fixes more nitrogen amounts compared to those lacking the mycorrhiza (Orwa et al., 2009). These results may add to determine the adaptive potential of other tree species which have the capability to revegetate new FA dumping sites. It could be important for linking phytoremediation research and its extension on the ground by practitioners for ecological restoration of FA dumps. 4. Conclusions Based on the present findings, it can be concluded that the manmade plantation on FA dump creates a good ecosystem towards sustainability. Due to increasing release of pollutants from coalbased thermal power stations, like suspended particulate matter, toxic elements, significant amount of CO2 generation etc., we should improve our understanding for planting trees on FA dumps to protect our precious environment in which we live. In this direction, the present field results may be used as a significant tool to develop green cover on new FA dumpsites through plantation and upgrading phytomanagement policies of FA dumpsite. 5. Conflict of interest statement The authors declare no conflict of interest. Acknowledgements Financial support given to first author by Science and Engineering Research Board (No. SR/FTP/ES-96/2012), Govt. of India is gratefully acknowledged. The authors would like to thank the Panki Thermal Power Station for access to the plantation site of fly ash dumps. Authors are also thankful to Director, CSIR-National Botanical Research Institute, Lucknow for his kind support. References Babu, A.G., Reddy, M.S., 2011. Diversity of arbuscular mycorrhizal fungi associated with plants growing in fly ash pond and their potential role in ecological restoration. Curr. Microbiol. 63, 273–280. Bajpai, O., Kushwaha, A.K., Srivastava, A.K., Pandey, J., Chaudhary, L.B., 2015. Phytosociological status of a monotypic genus Indopiptadenia: a near threatened tree from the Terai–Bhabar Region of Central Himalaya. Res. J. For. 9 (2), 35–47. Brewbaker, J.L., 1992. Pithecellobium dulce—sweet and thorny. NFT Highlights 92, 2. Carlson, C.L., Adriano, D.C., 1993. Environmental impacts of coal combustion residues. J. Environ. Qual. 22, 227–247.
Density (100 m−2 )
Regeneration status
Tree
Sapling
Seedling
0.59 0.07 0.37 0.52 0.59 0.48 0.30 1.89 0.96 2.59 0.59 0.81
17.75 Nil 0.31 0.47 Nil 0.34 0.22 37.85 26.48 204.76 15.87 33.78
Nil Nil 0.24 8.75 Nil 10.45 7.54 241.82 157.94 378.57 Nil 115.04
Poor No regeneration Fair Fair No regeneration Fair Fair Good Good Good Poor Good
Castro, K.L., 2000. Estudios de germinación en Jaúly Cenízaro. Boletín-Mejoramiento Genéticoy Semillas Forestales 24, 1–5. Curtis, J.T., McIntosh, R.P., 1950. The interrelations of certain analytic and synthetic phytosociological characters. Ecology 31 (3), 434–455. El-Keblawy, A., Al-Rawai, A., 2005. Effects of salinity, temperature and light on germination of invasive Prosopis juliflora (Sw.) D.C. J. Arid Environ. 61, 555–565. Felker, P., 2009. Unusual physiological properties of the arid adapted tree legume Prosopis and their applications in developing countries. In: De La Barrera, E., Smith, W.K. (Eds.), Perspectives in Biophysical Plant Ecophysiology: A Tribute to Park S. Nobel. Universidad Nacional Autonoma de Mexico, pp. 221–255. George, J., Masto, R.E., Ram, L.C., Das, T.B., Rout, T.K., Mohan, M., 2015. Human exposure risks for metals in soil near a coal-fired power-generating plant. Arch. Environ. Contam. Toxicol. 68, 451–461. Guedje, N.M., Lejoly, J., Nkongmeneck, B.A., Jonkers, W.B.J., 2003. Population dynamics of Garcinia lucida (Clusiaceae) in Cameroonian Atlantic forests. For. Ecol. Manage. 177, 231–241. Gupta, A.K., Sinha, S., 2008. Decontamination and/or revegetation of fly ash dykes through naturally growing plants. J. Hazard. Mater. 153, 1078–1087. Handa, A.K., Nandini, D., Uma, 2005. An alternative source of biofuel, seed germination trials of Pongamia pinnata. Int. J. Usufructs Manage. 6, 75–80. Haynes, R.J., 2009. Reclamation and revegetation of fly ash disposal sites—challenges and research needs. J. Environ. Manage. 90, 43–53. Jambhulkar, H.P., Juwarkar, A.A., 2009. Assessment of bioaccumulation of heavy metals by different plant species grown on flyash dump. Ecotoxicol. Environ. Saf. 72, 1122–1128. Juwarkar, A.A., Jambhulkar, H.P., 2008. Restoration of fly ash dump through biological interventions. Environ. Monit. Assess. 139, 355–365. Kostic, O., Mitrovic, M., Kneˇzevic, M., Jaric, S., Gajic, G., Djurdj, L., Evic Pavlovic, P., 2012. The potential of four woody species for the revegetation of fly ash deposits from the ‘Nikola Tesla-A’ thermoelectric plant (Obrenovac Serbia). Arch. Biol. Sci. 64 (1), 145–158. Krebs, C.J., 1989. Ecological methodology. Harper and Row Publication, New York, NY. Krzaklewski, W., Pietrzykowski, M., Wos, B., 2012. Survival and growth of alders (Alnus glutinosa (L.) Gaertn. and Alnus incana (L.) Moench) on fly ash technosols at different substrate improvement. Ecol. Eng. 49, 35–40. Kumari, A., Pandey, V.C., Rai, U.N., 2013. Feasibility of fern Thelypteris dentata for revegetation of coal fly ash landfills. J. Geochem. Explor. 128, 147–152. Lee, H., Ha, H.S., Lee, C.H., Lee, Y.B., Kim, P.J., 2006. Fly-ash effect on improving soil properties and rice productivity in Korean paddy soils. Bioresour. Technol. 97, 1490–1497. Maiti, S.K., Jaiswal, S., 2008. Bioaccumulation and translocation of metals in the nat-ural vegetation growing on fly ash lagoons: a field study from Santaldih thermal power plant, West Bengal, India. Environ. Monit. Assess. 136, 355–370. Misra, R., 1968. Ecology Work Book. Oxford and IBH Publishing Company, New Delhi. ´ M., Jaric, ´ S., Kostic, ´ O., Gajic, ´ G., Karadˇzic, ´ B., Lola Djurdjevic, ´ L., Oberan, L., Mitrovic, ´ M., Pavlovic, ´ P., 2012. Photosynthetic efficiency of four ´ D., Pavlovic, Pavlovic, woody species growing on fly ash deposits of a Serbian ‘Nicola Tesla-A’ Thermoeclectric Plant. Pol. J. Environ. Stud. 21 (5), 1339–1347. Mitrovic, M., Pavlovic, P., Lakusic, D., Djurdjevic, L., Stevanovic, B., Kostic, O., Gajic, G., 2008. The potential of Festuca rubra and Calamagrostis epigejos for the revegetation of fly ash deposits. Sci. Total Environ. 407, 338–347. Orwa, C., Mutua, A., Kindt, R., Jamnadass, R., Anthony, S., 2009. Agroforestree Database: A Tree Reference and Selection Guide Version 4.0. World Agroforestry Centre, Kenya. Pandey, V.C., 2015. Assisted phytoremediation of fly ash dumps through naturally colonized plants. Ecol. Eng. 82, 1–5. Pandey, V.C., Abhilash, P.C., Singh, N., 2009a. The Indian perspective of utilizing fly ash in phytoremediation, phytomanagement and biomass production. J. Environ. Manage. 90, 2943–2958. Pandey, V.C., Abhilash, P.C., Upadhyay, R.N., Tewari, D.D., 2009b. Application of fly ash on the growth performance, translocation of toxic heavy metals within
44
V.C. Pandey et al. / Urban Forestry & Urban Greening 15 (2016) 40–44
Cajanus cajan L.: implication for safe utilization of fly ash for agricultural production. J. Hazard. Mater. 166, 255–259. Pandey, V.C., Bajpai, O., Pandey, D.N., Singh, N., 2015a. Saccharum spontaneum: an underutilized tall grass for revegetation and restoration programs. Genet. Resour. Crop Evol. 62 (3), 443–450. Pandey, V.C., Kumar, A., 2013. Leucaena leucocephala: an underutilized plant for pulp and paper production. Genet. Resour. Crop Evol. 60, 1165–1171. Pandey, V.C., Prakash, P., Bajpai, O., Kumar, A., Singh, N., 2015b. Phytodiversity on fly ash deposits: evaluation of naturally colonized species for sustainable phytorestoration. Environ. Sci. Pollut. Res. 22, 2776–2787. Pandey, V.C., Singh, B., 2012. Rehabilitation of coal fly ash basins: current need to use ecological engineering. Ecol. Eng. 49, 190–192. Pandey, V.C., Singh, J.S., Kumar, A., Tewari, D.D., 2010. Accumulation of heavy metal by chickpea grown in fly ash treated soil: effect on antioxidants. Clean—Soil Air Water 38, 1116–1123. Pandey, V.C., Singh, J.S., Singh, R.P., Singh, N., Yunus, M., 2011. Arsenic hazards in coal fly ash and its fate in Indian scenario. Resour. Conserv. Recycl. 55, 819–835. Pandey, V.C., Singh, K., 2011. Is Vigna radiata suitable for the revegetation of fly ash landfills? Ecol. Eng. 37, 2105–2106. Pandey, V.C., Singh, K., Singh, R.P., Singh, B., 2012. Naturally growing Saccharum munja on the fly ash lagoons: a potential ecological engineer for the revegetation and stabilization. Ecol. Eng. 40, 95–99. Pandey, V.C., Singh, N., 2010. Impact of fly ash incorporation in soil systems. Agric. Ecosyst. Environ. 136, 16–27. Pandey, V.C., Singh, N., 2014. Fast green capping on coal fly ash basins through ecological engineering. Ecol. Eng. 73, 671–675. Pandey, V.C., Singh, N., Singh, R.P., Singh, D.P., 2014. Rhizoremediation potential of spontaneously grown Typha latifolia on fly ash basins: study from the field. Ecol. Eng. 71, 722–727. Pietrzykowski, M., Krzaklewski, W., Gaik, G., 2010. Assessment of forest growth with plantings dominated by Scots pine (Pinus sylvestris L.) on experimental plots on a fly ash disposal site at the Bełchatow power plant. Environ. Eng. 137 (17), 65–74 (In Polish, English summary). Rai, U.N., Pandey, K., Sinha, S., Singh, A., Saxena, R., Gupta, D.K., 2004. Revegetating fly ash landfills with Prosopis juliflora L.: impact of different amendment and Rhizobium inoculation. Environ. Int. 30 (3), 293–300. Ram, L.C., Jha, S.K., Tripathi, R.C., Masto, R.E., Selvi, V.A., 2008. Remediation of fly ash landfills through plantation. Biorem. J. 18, 71–90. Ram, L.C., Masto, R.E., 2010. An appraisal of the potential use of fly ash for reclaiming coal mine spoil. J. Environ. Manage. 91, 603–617. Ram, L.C., Srivastava, N.K., Jha, S.K., Sinha, A.K., Masto, R.E., Selvi, V.A., 2007. Management of lignite fly ash through its bulk use via biological amendments for improving the fertility and crop productivity of soil. Environ. Manage. 40, 438–452.
Ram, L.C., Srivastava, N.K., Tripathi, R.C., Jha, S.K., Sinha, A.K., Singh, G., Manoharan, V., 2006. Management of mine spoil for crop productivity with lignite fly ash and biological amendments. J. Environ. Manage. 79, 173–187. Rau, N., Mishra, V., Sharma, M., Das, M.K., Ahaluwalia, K., Sharma, R.S., 2009. Evaluation of functional diversity in rhizobacterial taxa of a wild grass (Saccharum ravennae) colonizing abandoned fly ash dumps in Delhi urban ecosystem. Soil Biol. Biochem. 41, 813–821. Ribeiro, J., Silva, T.F., Mendonc¸a Filho, J.G., Flores, D., 2014. Fly ash from coal combustion—an environmental source of organic compounds. Appl. Geochem. 44, 103–110. Scott, P.T., Pregelj, L., Chen, N., Hadler, J.S., Djordjevic, M.A., Gresshoff, P.M., 2008. Pongamia pinnata: an untapped resource for the biofuels industry of the future. Bioenergy Res. 1, 2–11. Singh, J.S., Pandey, V.C., 2013. Fly ash application in nutrient poor agriculture soils: impact on methanotrophs population dynamics and paddy yields. Ecotoxicol. Environ. Saf. 89, 43–51. Singh, J.S., Pandey, V.C., Singh, D.P., 2011. Coal fly ash and farmyard manure amendments in dry-land paddy agriculture field: effect on N-dynamics and paddy productivity. Appl. Soil Ecol. 47, 133–140. Srivastava, N.K., Ram, L.C., Masto, R.E., 2014. Reclamation of overburden and lowland in coal mining area with fly ash and selective plantation: a sustainable ecological approach. Ecol. Eng. 71, 479–489. Sujatha, K., Panda, B.M., Hazra, S., 2008. De novo organogenesis and plant regeneration in Pongamia pinnata, oil producing tree legume. Trees 22, 711–716. Tiwari, S., Kumari, B., Singh, S.N., 2008. Evaluation of metal mobility/immobility in fly ash induced by bacterial strains isolated from the rhizospheric zone of Typha latifolia growing on fly ash dumps. Bioresour. Technol. 99, 1305–1310. Tropek, R., Cerna, I., Straka, J., Cizek, O., Konvicka, M., 2013. Is coal combustion the last chance for vanishing insects of inland drift sand dunes in Europe? Biol. Conserv. 162, 60–64. Tropek, R., Cerna, I., Straka, J., Kadlec, T., Pech, P., Tichanek, F., Sebek, P., 2014. Restoration management of fly ash deposits crucially influence their conservation potential for terrestrial arthropods. Ecol. Eng. 73, 45–52. Uma Shankar, 2001. A case of high tree diversity in a Sal (Shorea robusta)—dominated low land forest of eastern Himalaya: floristic composition, regeneration and conservation. Current Science 81, 776–786. Verma, S.K., Masto, R.E., Gautam, S., Choudhury, D.P., Ram, L.C., Maiti, S.K., Maity, S., 2015. Investigations on PAHs and trace elements in coal and its combustion residues from a power plant. Fuel 162, 138–147. Zimmerman, H.G., 1991. Biological control of mesquite, Prosopis spp. (Fabaceae), in South Africa. Agric., Ecosyst. Environ. 37, 175–186.