NSave Nature to Survive

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1 ISSN: NSave Nature to Survive : Special issue, Vol. III: ; 2013 AN INTERNATIONAL QUARTERLY JOURNAL OF ENVIRONMENTAL SCIENCES THE HEIGHT: DIAMETER RATIO DEPENDENT ECECIS OF NATIVE PLANT SEEDLINGS: IMPLICATION IN RESTORATION OF OVERBURDEN DUMPS Chitralekha Sengupta and Anshumali KEYWORDS Mine spoil Overburden dumps Organic manure VAM Tropical deciduous forests Height Diameter ratio Ecesis. Prof. P. C. Mishra Felicitation Volume Paper presented in National Seminar on Ecology, Environment & Development January, 2013 organised by Deptt. of Environmental Sciences, Sambalpur University, Sambalpur Guest Editors: S. K. Sahu, S. K. Pattanayak and M. R. Mahananda 281

2 NSave Nature to Survive QUARTERLY CHITRALEKHA SENGUPTA* AND ANSHUMALI Chitralekha Sengupta,Senior Research Fellow,Central Pollution Control Board, Zonal Office, Southend Conclave, 1582 Rajdanga Main Road, Kolkata Department of Environmental Science and Engineering Indian School of Mines, Dhanbad, Jharkhand, INDIA chitra82ster@gmail.com. ABSTRACT The ecological performance of native tree seedlings was examined by plot experiments to understand the reclamation mechanism of overburden dump in Bastacola area of Jharia Coalfield. Plant species selected for plot experiments were Neem (Azardirachta indica), Ashok (Saraca indica), Bamboo (Dendrocalamus strictus), Peepal (Ficus religiosa) and Amla (Emblica officinalis). The seedlings were subjected to three types of treatments namely OBV (VAM), OBS (agricultural soil+vam), OBM (cow dung manure+vam) and OBC (the control plot). The physico-chemical characteristics of each plot was evaluated along with the plant root, shoot height and circumference growth in each plot. The OBM showed high growth of plant seedlings due to the organic manure addition while OBC was not significant for plant growth due to lack of nutrient despite the occurrence of high orthodox organic matter in form of coal dust. The treatments helped in shoot and root growth of D. strictus and F. religiosa, respectively while the annual increment in height and circumference was maximum in D. strictus and F. religiosa, respectively. The low H: D ratio revealed high versatility of F. religiosa i.e. preferred plant species for the restoration of the overburden dump on flat and sloping surfaces in the study area. INTRODUCTION Today, India has 18, 289h of degraded land due to coal mining (Agarwal and Shahi, 2004). Hillocks of disturbed soil profile, called overburden dumps are usual in mining areas. These are major causes of air and water pollution. They also subside/collapse due to lose rocks assemblage. These problems can be curbed with plantation, however, lack of nutrients, high bulk density and low water holding capacity and high degree of homogeneity in parent rock materials lead to poor chances of plant species survival. Therefore, natural restoration of mine spoil is a slow process (Singh, 2006). To support the plants growth, spoil amendment is required for their ecesis on bare over burden dumps. The treatment of mine spoils along with beneficial soil microorganisms like arbuscular mycorrhizal fungi (AMF) also facilitate the plant growth by effective exploitation of essential nutrients and water from soil due to the extensive network of AMF mycelium (Joner and Jacobsen, 1995; Juwarkar and Jambhulkar, 2008; Sinha et al., 2009). The use of native and indigenous plant species have been a key factor in revegetation programs with a view to maintain essential processes and life support system, preservation of genetic diversity and to ensure sustainable utilization of species and ecosystem (Banerjee et al., 1996; Jha and Singh 1993; Soni and Sharma, 1994) as they undergo minimum environmental stress, successfully establish themselves on the degraded soil (Singh et al., 2002) and improve understory properties. In the tropical deciduous forests, slopes are generally dominated by dicot plants with simple leaves while flat surface or hill tops are dominated by dicot with compound leaves or monocot plants. The idea behind this natural growth pattern has been exploited in our study to the find out the most suitable plant species for successful ecesis on the overburden dump of Bastacola, Jharia. MATERIALS AND METHODS *Corresponding author Study area The study site is located in Bastacola, Jharia coalfield of Jharkhand [23º39 30" and 24º48 20 N latitude and between 86º11 30" and 86º27 E longitude] (Fig. 1). It has an average elevation of 77m; the climate is tropical monsoon with annual average rainfall is 1169 mm. The mean monthly maximum and minimum temperature during study period (April 2008-July 2009) were, ºC in summer, ºC in winter and ºC in monsoon season. The relative humidity varied from %. The geological formation belongs to the Gondwana System (Barakar formation), the lower division of which comprises the most important coal measures of India (Chandra, 1992). This is important formation containing coal seams and covers an area of about 210 sq km (Fig. 1). The Barakar Formation consists of coarsegrained sand-stones, conglomerates, shales, carbonaceous shales, silt-stones, 282

3 IMPLICATION IN RESTORATION OF OVERBURDEN DUMPS Table 1: Summary of control and treatment plots Plot No Abbreviation Remarks Over Burden Control OBC Mine spoil, seedlings of five plant species, no amendments Over Burden + VAM OBV Mine spoil, seedlings of five plant species, treatment with vesicular arbuscular mycorrhizae (VAM) Over Burden +VAM+ Agricultural Soil OBS Mine spoil, seedlings of five plant species, treatment with vesicular arbuscular mycorrhizae (VAM) and agricultural soil to mine spoil ratio was 1:4 Over Burden + VAM + Manure OBM Mine spoil, seedlings of five plant species, treatment with vesicular arbuscular mycorrhizae (VAM) and manure to mine spoil ratio was 1:4 Table 2: Physico chemical parameters of the coal mine spoil, agricultural soil and cow dung manure which were used as soil amendments April, 2008 Parameters Mine Spoil (Avg±Sd) Agriculture soil (Avg±Sd) Cow dung manure (Avg±Sd) ph 5.67± ± ±0.05 EC(mmhos/cm) 0.07± ± ±0.01 BD(g/cc) 1.45± ± ±0.22 MC(%) 2.07± ± ±0.24 WHC(%) 16.28± ± ±0.01 OC(%) 1.66± ± ±0.07 OM(%) 2.87± ± ±0.93 N( μg/g) 16.67± ± ±0.98 P(μg/g) 1.80± ± ±0.23 Mg(μg/g) 8.22± ± ±1.12 Ca(μg/g) ± ± ±2.05 Na(μg/g) 32.15± ± ±1.30 K(μg/g) 49.63± ± ±1.64 CEC(meq/100g) 6.89± ± ±0.07 %Sand (>63μm) 73± ± %Silt (<63 to 2μm ) 21.4± ± %Clay(<2μm) 6± ± Meliaceae), Ashok (Saraca indica: Fabaceae), Bamboo (Dendrocalamus strictus: Poaceae), Peepal (Ficus religiosa: Moraceae) and Amla (Emblica officinalis: Phyllanthaceae). The mine spoils were collected from Bastacola OCP, Jharia. Then it was transported to the Experimental Garden of ISM for plot experiments. The agricultural soils were also collected from Bastacola region. The cow dung manure was collected from local people and VAM tablets (Glomus sp) were obtained from KCP sugar and Industries Corporation, Vuyyuru, Andhra Pradesh. In OBM plot, the ratio of manure:spoil was 1:4. Figure 1: Study area showing location of coal mine spoil (Chandra, 1992) fireclays and coal seams. The mine-soil is fresh and contains approximately 80% sand, 11% clay and a low concentration of nutrients. Experimental design One control and three treatment plots (4x4m 2 ) were established and maintained at ESE Experimental Garden from April 2008 to July In these plots OB materials filled up to 3 feet depth and the volume of each plot was 14.6m 3. The composition of control and three types of treatment plots used in the experiment are given in Table 1. The two months old seedlings of five plant species grown in the mixed plantation were Neem (Azardirachta indica: Laboratory methods The physico-chemical properties of the coal mine spoils, agricultural soils and organic manure, control and treatment plots were determined as per the standard procedures (Jackson, 1973) to assess the seasonal variation in mine spoil characteristics and the effect of treatments on the fertility of substrate as well growth and development of plant seedlings. Auger was used as a sampling tool to draw the samples at a depth of 0-10 cm. The samples were dried at room temperature and stored in plastic bags, a 100g homogenized samples were drawn and ground to pass through 2mm sieve before laboratory analysis. Plant biomass was estimated on dry weight basis at 70ºC (Jackson, 1973). The relative growth rate (RGR) in height (RGRH) and circumference (RGRC) was estimated using the formula (Hunt, 1978): RGR = (ln h 2 ln h 1 ) / t 2 - t 1 Where h is height or circumference at initial time (t 1 ) and final 283

4 CHITRALEKHA SENGUPTA AND ANSHUMALI Table 3: Physico-chemical parameters of the control and treatment plots OBC(Avg±Sd) OBV(Avg±Sd) Parameters M, 2008 (4 mo) W, 2009(8 mo) S, 2009(12 mo) M, 2008(4 mo) W, 2009(8 mo) S, 2009(12 mo) ph 6.21± ± ± ± ± ±0.32 EC(mmhos/cm) 0.17± ± ± ± ± ±0.04 BD(g/cc) 1.45± ± ± ± ± ±0.02 MC (%) 1.59± ± ± ± ± ±0.09 WHC (%) 18.20± ± ± ± ± ±0.32 OC (%) 0.97± ± ± ± ± ±0.11 OM (%) 1.68± ± ± ± ± ±18 Avai-N(μg/g) 23.23± ± ± ± ± ±3.11 Avai-P(μg/g) 1.95± ± ± ± ± ±0.82 Exch-Mg(μg/g) 18.48± ± ± ± ± ±2.37 Exch-Ca (μg/g) ± ± ± ± ± ±10.55 Exch-Na(μg/g) 39.20± ± ± ± ± Exch-K(μg/g) 57.20± ± ± ± ± ±19.71 CEC(meq/100g) 5.28± ± ± ± ± ±0.75 OBS(Avg±Sd) OBM(Avg±Sd) Parameters M, 2008 (4 mo) W, 2009 (8 mo) S, 2009 (12 mo) M, 2008 (4 mo) W, 2009 (8 mo) S, 2009 (12 mo) ph 6.55± ± ± ±0.20 EC(mmhos/cm) 0.70± ± ± ± ± ±0.06 BD(g/cc) 1.33± ± ± ± ± ±0.002 MC (%) 1.75± ± ± ± ± ±0.06 WHC (%) 25.63± ± ± ± ± ±0.76 OC (%) 2.16± ± ± ± ± ±0.21 OM (%) 3.74± ± ± ± ± ±0.38 Avai-N(μg/g) 34.98± ± ± ± ± ±6.95 Avai-P(μg/g) 8.23± ± ± ± ± ±2.77 Exch-Mg (μg/g) 54.47± ± ± ± ± ±4.77 Exch-Ca (μg/g) ± ± ± ± ± ±79.14 Exch-Na (μg/g) 47± ± ± ± ± ±4.21 Exch-K(μg/g) 68.4± ± ± ± ±22.60 CEC (meq/100g) 10.42± ± ± ± ± ±1.1 time (t 2 ) in months. To compare experimental plantation of various treatment and control plots, annual increment (I) in height and circumference was calculated per species using the following formula (Pedraza and Williams-Linera, 2003). I = (h 1 h 2 ) / t Where h 1 and h 2 are heights or circumferences at times 1 and 2 and t is the total time in years. One Way ANOVA was performed using SPSS 10. Comparison among means was carried out using Duncan Multiple Range Test (DMRT) at a significance level of p<0.05. RESULTS AND DISCUSSION Biogeochemistry of mine spoils in control and treatment plots The average value of ph of the mine spoil was slightly acidic (5.67), poor electrical conductivity (0.07mmhos/cm) showed low soluble salts and high bulk density (1.45 g/cc) revealed dominance of silt and sand particles (Table 2), which might be responsible for low moisture content, water holding capacity, organic carbon, available nutrients and microbial activity. Further, these biogeochemical factors may be responsible for week cation exchange capacity (6.89 meq/100g). The physicochemical properties of agricultural soil and cow dung manure were assessed and showed good fertility status (Table 2). Moreover, the properties of cow dung manure were relatively better as compared to the agricultural soils. Juwarkar and Jambhulkar (2008) studied the available nutrient contents in coal mine spoils and found N, P and K concentrations were 17, 20 and 60ìg/g, respectively. Changes in the physico-chemical properties of coal mine spoil were evaluated seasonally which are given in Table 3. The ANOVA revealed significant treatment impact on seedling growth performance (Table 4), which varied considerably from species to species (Fig. 2a and b). Furthermore, the organic manure addition improved the mine spoils fertility status by 2-10 times more than VAM treatment and 1-2 times more than agricultural soil amendments. Seasonal Changes in mine spoil characteristics revealed that the spoil amendments (VAM, agricultural soils and organic manure) enhanced the spoil fertility by increasing ph. The high CEC showed retention of essential nutrients in the rhizosphere after decomposition of organic matter while decreased bulk density lead to reduced compaction, facilitated aeration, better penetration and spreading of roots, thereby making the rhizosphere favourable for massive root Table 4: F values (p<0.05) of shoot biomass (SB), root biomass (RB), height (H) and circumference (C) for seedlings of plant species Plant species F SB F RB F H F C A. indica E. officinalis D. strictus F. religiosa S. indica

5 IMPLICATION IN RESTORATION OF OVERBURDEN DUMPS Plant root and shoot dry wt. (g) Initial shoot dry wt. Final shoot dry wt. Initial root dry wt. Final root dry wt. 1 OBC 2 OBV 3 OBS 4 OBM Plant height (cm) Initial ht. Final ht. 1 OBC 2 OBV 3 OBS 4 OBM A.indica D.strictus E. officinalis F. religiosa S. indica Figure 2a: Initial (2 months) and final (12 months) root and shoot biomass (dry weight, g control and treatment plots development. This gradual increase in favourable physico - chemical properties and nutrient availability in OBC<OBV<OBS<OBM plots facilitate the growth of plant seedlings in rhizosphere. Seedling biomass and H:D ratio The significant shoot biomass was observed for D. strictus irrespective of plots while the seedlings of F. religiosa showed maximum root biomass (Table 5). The high shoot biomass of D. strictus seedlings can be attributed to significant increase in the height. Moreover, the significant shoot biomass in the OBV compared to OBC plot for most the plant seedlings indicate VAM could have resulted in an increased nutrient uptake by merely shortening the distance that the nutrients had to diffuse from the soil to the roots. Many studies showed a positive relationship between dry matter yield increment and VAM inoculations (Allen et al., 1981; Chulan and Martin, 1992; Zajicek et al., 1987). Li et al. (1991) showed that when root exploration is restricted then up to 80% of the plant A.indica D.strictus E. officinalis F. religiosa S. indica Figure 2b: Initial (2 months) and final (12 months) height (cm) in control and treatment plots phosphorus can be delivered by the external VAM hyphae to the host plant over a distance of more than 10 cm from the root surface. The circumference showed descending trend as F. Religiosa > A. Indica > D. Strictus > E. Officinalis > S. indica (Table 5). The H: D ratio revealed that all seedlings showed maximum responses to treatments in terms of height growth (i.e. increased H: D ratio) except F. religiosa where amendments resulted in more resource allocation in fine root and circumference development (i.e. decreased H: D ratio) (Table 6). Consequently, the relationship between annual increment in height and circumference is highly positive in F. Religiosa while disproportionately large increase in height with respect to circumference may be responsible for poor R 2 value in D. strictus (Fig. 3). Singh et al. (2000) found similar response to nutrient enrichment for non-leguminous species planted on mine spoils. Generally, the trees that allocate comparatively less resources to stem per unit of height growth are assumed Table 5: Percentage increase in root biomass, shoot biomass, circumference and height of the plants from Jun 08 to Jul 09, of the plant species under the control and treatment conditions along with Duncan s Test depicting the effect of treatment on the shoot biomass (SB), root biomass (RB), height (H) and circumference (C) of the plant species Plant species Control and Treatment Plots % Increase in Parameters OBC OBV OBS OBM Root Biomass (June 08- July 09) A. indica c b ab a E. officinalis d c b a D. strictus b b a a F. religiosa c c b a S. asoka 8.80 c b ab a A. indica d c b a Shoot Biomass E. officinalis 7.42 c b b a D. strictus d c b a F. religiosa c b a a S. asoka 5.74 b b b a A. indica c c b a Circumference E. officinalis b b a a D. strictus b b ab a F. religiosa c c b a S. asoka 0 a 1.96 a 7.69 a 7.51 a A. indica c b b a Height E. officinalis c c b a D. strictus d c b a F. religiosa c cb b a S. asoka 3.15 a 3.49 a 5.68 a 6.12 a 285

6 CHITRALEKHA SENGUPTA AND ANSHUMALI Annual increment in circumference (cm) y = 0.046x R 2 = A. indica OBC OBV y = 0.007x R 2 = OBS OBM E..officinalis Annual increment in circumference (cm) y = 0.007x R 2 = D. strictus y = 0.048x R 2 = F. religiosa Annual increment in circumference (cm) y = 0.027x R 2 = S. indica Figure 3: Relationship between annual increment in circumference and height of five plant species to grow taller than those that allocate more (King, 1981; Lawton, 1984; Singh et al., 2000). Further, the low annual increment in height i.e. decreased RGRH and significant annual increment in circumference i.e. increased RGRC (Table 6), support versatile nature of F. religiosa in terms of better spoil binder, lesser chances of getting uprooted in stress conditions, control spoil erosion and water body siltation and promote slope stabilization. CONCLUSIONS The amendments of coal mine spoils improved spoil characteristics as indicated by positive response of plant seedlings to OBV and OBM treatment in terms of root and shoot growth. The D. strictus with quick and vigorous shoot growth observed to be suitable for plantation on flat surfaces of the dump. Since D. strictus showed good growth even in nutrient deficient control plot so its versatility is undoubtedly wide, however, due to high H:D ratio, its plantation along the slopes should be discouraged as it has greater chances of getting uprooted. The F.religiosa showed positive relationship between annual increment in height and circumference, hence, it can be used in the restoration of the overburden dump even on slopes and flat surface. Similarly, E. officinalis and A. indica would best serve for the restoration of the overburden dump on flat surfaces. However, S. indica needs proper hardening before its plantation in coal mine spoils. Such short term studies can help in choosing suitable native plant species for successful ecesis during secondary succession of mined out areas. ACKNOWLEDGEMENTS The authors are grateful to MHRD, GOI, for providing financial assistance to conduct the research work. We are thankful to BCCL for providing the study area and District Forest Department, Dhanbad, for imparting valuable information about plant seedlings. The authors also express sincere thanks to the Department of Environmental Science and Engineering, ISM, Dhanbad, for providing financial support and laboratory 286

7 IMPLICATION IN RESTORATION OF OVERBURDEN DUMPS Table 6. H:D ratio, relative growth rate (RGR) in height (RGRH, cm/month), circumference (RGRC, cm/month), annual increment in height (cm) and circumference (cm), between June 08 and July 09 in control plot and experimental plots. Plant species OBC OBV OBS OBM Parameter A. indica 77.15± ± ± ±3.38 H:D ratio E. officinalis ± ± ± ±13.11 D. strictus ± ± ± ±18.24 F. religiosa 51.23± ± ± ±1.10 S. indica 98.19± ± ± ±12.04 A. indica 0.026± ± ± ±0.005 RGRH (cm/month) E. officinalis ± ± ± ±0.002 D. strictus 0.029± ± ± ±0.002 F. religiosa 0.018± ± ± ±0.007 S. indica 0.002± ± ± ±0.00 A. indica 0.008± ± ± ±0.001 RGRC(cm/month) E. officinalis 0.008± ± ± ±0.003 D. strictus 0.01± ± ± ±0.008 F.religiosa 0.01± ± ± ±0.003 S. indica ± ±0.006 A. indica 18.11± ± ± ± 2.97 Annual increment inheight (cm) E. officinalis ± ± ± ±1.94 D. strictus 21.60± ± ± ± 0.40 F.religiosa 6.24± ± ± ±2.22 S. indica 1.48± ± ± ±0.58 A. indica 0.24± ± ± ±0.23 Annual increment in circumference (cm) E. officinalis 0.15± ± ± ±0.05 D. strictus 0.24± ± ± ± 0.19 F.religiosa 0.21± ± ± ±0.05 S. indica ± ± ± facilities to conduct this research work. REFERENCES Agarwal, A. K. and Shahi, S Management of post mining land and ISO: for Indian Mines, NSEEME, ISM, Dhnabad on March, Allen, M. F., Smith, W. K., Moore Jr, T. S. and Christensen, M Comparative water relations and photosynthesis of mycorrhizal Bouteloua gracilis H.B.K. lag ex Steud. New Phytologist. 88: Banerjee, S. K., Williums, A. J., Biswas, S. C., Manjhi, R. B. and Mishra, T. K Dynamics of natural ecorestoration in coal mine overburden of dry deciduous zone of M.P. India. Ecology, Environment and Conservation. 2: Chandra, D Jharia Coalfield. Geological Society of India, Bangalore. Chulan, H. A. and Martin, K The vesicular-arbuscular (VA) mycorrhizal and its effects on growth of vegetatively propagated Theobroma cacao L. Plant and Soil. 144: Hunt, R Plant growth analysis. Studies in Biology no. 96. Edward Arnold (Publishers). London. Jackson, M. L Soil Chemical Analysis. Prentice Hall of India private Limited, New Delhi. Jha, A. K. and Singh, J. S Rehabilitation of mine spoils. pp In: J.S. Singh (ed.) Restoration of Degraded Land: Concepts and Strategies. Rastogi Publications, Meerut, India. Joner, E. J. and Jakobsen, I Growth and extracellular phosphatase activity of arbuscular mycorrhizal hyphae as influenced by soil organic matter. Soil Biology and Biochem. 27: Juwarkar, A. A. and Jambhulkar, H. P Phytoremediation of coal mine spoil dump through integrated biotechnological approach. Bioresource Technology Doi: /j. Biortech King, D. A Tree dimensions: maximizing the rate of height growth in dense stands. Oecologia. 51: Lawton, R.O Ecological constraints on wood density in a tropical montane rain forest. American J. Botany 71: Li X-L, E. G. and Marschner, H Extension of Phosphorus depletion zone in VA-mycorrhizal white clover in calcareous soil. Plant and Soil 136: Pedraza, R. A. and Williams-Linera, G Evaluation of native tree species for the rehabilitation of deforested areas in a Mexican cloud forest. New Forests. 26: Singh, A Growth and leaf nutrient status of companion species as influenced by neighbouring species in mixed plantations raised on mine spoil. Tropical Ecology 47(2): Singh, A., A., Jha, K. and Singh, J. S Effect of nutrient enrichment on native tropical trees planted on Singrauli Coalfields, India. Restoration Ecology. 8: Singh, A. N., Raghubanshi, A. S. and Singh, J. S Plantations as a tool for mine spoil restoration. Current Science 82: Sinha, S., Masto, R. E., Ram, L. C. Selvi, V. A., Srivastava, N. K., Tripathi, R. C. and George, J Rhizosphere soil microbial index of tree species in a coal mining ecosystem. Soil Biology and Biochemistry. 41: Soni, P. and Sharma, V. P Floristic composition in an age series of restored limestone mine. Journal of Tropical Forestry 10: Zajicek, J. M., Hetrick, B. A. D. and Albrecht, M. L Influence of drought stress and mycorrhizae on growth of two native forbs. J. American Society of Horticulture Science. 112(3):

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