Biodiversity of Grasses and Associated Vegetation on Different Aged Soil Dumps from Sonepur Bazari OCP, Raniganj Coalfield

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1 INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCES Volume 2, No 2, 2011 Copyright 2010 All rights reserved Integrated Publishing Association Research article ISSN Biodiversity of Grasses and Associated Vegetation on Different Aged Soil Dumps from Sonepur Bazari OCP, Sanjoy Kumar 1, Chaudhuri. S 2, Maiti. S.K 3 1, 3- Centre for Mining Environment, Indian School of Mines; Dhanbad Dept. Of Mining Engineering, Indian School of Mines; Dhanbad skumarism@gmail.com doi: /ijes ABSTRACT Five abandoned internal and external soil sites ranging from 2 years to 21 years in Sonepur Bazari OCP were selected from to evaluate plant invasion, establishment and biodiversity on disturbed sites. The floristic diversity of grasses and other associated herbaceous flora mainly the leguminous was analyzed from different aged soil s in coal mining area. The study was with a view to assess the vegetation and suggest management strategy for speeding up the tree forms in the area. The soil s in the initial stages had low flora diversity in the outslope areas which were less, both in number and abundance. The site mainly consists of grasses vegetation and spares growth of herbaceous plants. The middle aged soil s showed the medium vegetation growth in grasses and herbaceous plants. The er aged soil s has dense vegetation with diversity in grasses, herbaceous plants and trees growth. The different aged mine soil s contains forty two types of different species. At the six sites, among the grasses are Eragrostis variabilis, Eragrostis pacepera, Eragrostis atropiodes, Eragrostis minor, Dactyloctenium aegyptium, and Cynodon dactylon, among the herbaceous plants were Panicum dichotomiflorum, Setaria paniculifera, Desmodium triflorum Mimosa pudica, Lantana camara, Calotropis procera, and Argemone Mexicana and for the trees species are Dalbergia sisso, Azardirachta indica, Ziziphus jujube, Acacia auriculiformis, Cassia seamea, and Acacia nilotica were dominating flora at 2 years and 21 years mine soil s. Key words: Mining, Reclamation, Native Grasses, Biodiversity, Succession. 1. Introduction Land degradation due to the alteration and destruction of terrestrial habitat has become a major environmental concern throughout the tropics. One of the major factors responsible for such degradation is rapid industrialization and spread of mining activity which often result in the loss of the natural ecosystem with associated biodiversity (Ezeaku and Davidson, 2008). Diversity of species is a key characteristic of natural ecosystems. These ecosystems, in turn, form the basis of all ecosystem goods and services upon which sustainable livelihoods and food security depend. Historically, the mining sector has not recognized this, and mining activities have often resulted in destruction of or radical alterations to, whole ecosystems. In such cases, full recovery of these ecosystems and their components may take many years, possibly even millennia (Cooke, 1999). Consequently, the impacts on the biophysical environment caused by the mining and minerals processing industry have frequently been accompanied by a significant loss of biodiversity. This may pertain even when a mine is rehabilitated after closure. Current best practice attempts to avoid negative impacts and, Received on June 2011 Published on November

2 where necessary, to restore impacted environments. This is an essential step if the sector is to contribute significantly towards sustainable development in the region (Hoadley et al., 2002). Since restoration of the original forest ecosystem has failed, an alternative native ecosystem model must be explored. Establishment of a diverse prairie system would be more desirable than the current forage complex and may help remediate existing adverse soil conditions. Native prairie ecosystems are diverse, containing multiple species of grasses and other herbaceous plants, and are noted for their ability to increase soil quality and support complex faunal communities (Kline, 1997). However, the excavations process, especially lignite and coal mining, produce vast areas of degraded land which had obtained the conditions of primary succession. Several reports on the vegetation of s (Jochimsen et al., 1995) emphasize the slow rate of colonization which may be due either to the unfavorable substrate or the lack of suitable pioneer plants, because they have been exterminated to a large extent by man. The objective of this research was to examine the natural occurrence and growth of grasses and its associated herbaceous plant species native to different habitats across Raniganj Coalfield, West Bengal with the goal of increasing diversity and function on the surface opencast coal mined land. The study also enumerating to understands the native species of the ground flora existing there so as to promote the growth of the vegetation by supporting its protection and artificial regeneration which would prevails the conditions favorable for growth of trees species can be brought in easily to stabilise these mine soil s. The overall hypothesis is that by assessing which species are most successful at establishing on the mine soil s, generalizations can be made about the nature of the mine land habitat and its ability to support plants with a range of adaptive traits. 2. Materials and Methods 2.1 Location of the Area constitutes an important coalfield of India where coal mining started as early as 1774 by British owned companies and by various other private coal-mining companies of Bengal. In 1974 all the working mines were regrouped for effective management and exploitation strategy and since then this region is known as Eastern Coalfield of Coal India Limited. Geographically this coalfield lies between latitudes ' N and ' N and longitudes ' E and ' E. However, major portion (79%) of this coalfield lies in the interfluves of the Ajay and the Damodar rivers forming northern and southern boundary of the region, respectively. The northwestern margin is approximately marked by a north-south flowing Barakar river; however, the Coalfield limit extends beyond this along the Khudiya nala upto Nirsa town. Similarly, the limit of the eastern margin of presently extends upto Durgapur town but according to a recent survey, as reported by Geological Survey of India, it extends upto Panagarh - Domra area i.e. 20 km east of present margin. 728

3 3. Methodology 3.1 Mine details Figure 1: Sampling Points in The three mines from where the samples were collected are mechanized opencast coal mines. The locations of the mines have been shown in Figure 1. The brief details of the mines are given in Table 1. Table 1: The brief details of the mines Mining Properties Sonepur Bazarai OCP Geological Reserve (MT) Mineable reserve (MT) Rated capacity (mty) 3.4 Stripping ratio (m 3 /t) 4.72 Maximum depth of mine (m) 245 Minimum depth of mine (m) 61 Alluvial soil thickness (m) OB removal (million m 3 )

4 3.2 Field survey Field survey was conducted during the months of December 2010 and January Interactions with the local staff of ECL and with the local people of that particular region were made so as to incorporate the local names and utility of these species. Photography of the plants has been taken at the sites itself with the help of digital camera (Nikkon cyber shot, Model No-). GPS data has been recorded on the spot. Phonological observations were also recorded at both sites. All the specimens collected were serially numbered. Field notes were taken of the pertinent features. Efforts were made to identify the plants from fresh materials. Those that could not be satisfactorily identified in the field were brought to the laboratory and identifies by checking it with monographs, herbarium specimens and other relevant available literature. Herbarium specimens were prepared of the collected species. 4. Results and Discussions The different grasses and associated plants species collected from five mine soil s are shown in Table 2. There were substantial difference in species composition among the five different sites and positions. The study also reveals that the vegetation varied from newly formed soil s to er aged soil s. The most striking feature was that when we preceding towards the upper aged limits of soil s the vegetation densities were increased. Table 2: The lists of plants collected from the five different sites. S.No Botanical name Habitat 2 yrs 1 Eragrostis variabilis 2 Eragrostis pacepera 3 Eragrostis atropiodes 6 yrs 9 yrs 16 yrs 21 yrs Grass p p p p p Grass p p p p p Grass p p p p p 4 Eragrostis minor Grass p p p p p 5 Dactyloctenium Grass a p p p p aegyptium 6 Cynodon dactylon Grass p p p p p 7 Digitaria Grass a a p p p microbachne 8 Echirnochola Grass a a a p p calona 9 Perotis indica Herbs a a a p p 10 Alloteropsis Grass a a p p p semialata 11 Cyrtococcum Herbs a a a p p accrescens 12 Echinochloa Herbs p p a p a colone 13 Andropogan Herbs p p p p p distachya 14 Brachiaria Herbs p p p p p distachya 15 Panicum Herbs p p p p P 730

5 dichotomiflorum 16 Setaria Herbs a p p a a paniculifera 17 Desmodium Herbs p p p p p triflorum 19 Cyperus rotundus Herbs p p p p p 20 Alternanthera Herbs a a a a p sessilis 21 Evolvulus Herbs a p p p p nummularis 22 Tephrosia Herbs a a p p p purpera 23 Mimosa pudica Herbs p p p p p 24 Lantana camara Herbs p p p p p 25 Calotropis Herbs p p p p p procera 26 Argemone Herbs p p p p p Mexicana 27 Turnera ulmifolia Herbs a a a p a 28 Ricinus communis Herbs a p p a a 29 Crotalaria retusa Herbs p p a p p 30 Heliotropium Herbs a a a p p indica 31 Agrotis Herbs a a p p p stolonifera 32 Ocimum sanctum Herbs a p p p p 33 Urena lobata Herbs a a a a p 34 Sida acuta Herbs p p p p p 35 Datura Herbs p p p p p spcemonium 36 Acacia Herbs a a a p p auriculiforms 37 Dalbergia sisso Trees a a p p p 38 Azardirachta Trees a a a p p indica 39 Ziziphus jujuba Trees p p p p p 40 Acacia Trees a a a p p auriculiformis 41 Cassia seamea Trees a a a p p 42 Acacia nilotica Trees a a a p P Reforestation on out slope positions is progressing much more quickly than on flat top positions. The number of species, density, and size of trees on outslopes are generally much greater than adjacent flat top positions. It appears, based on stem densities alone, that the 9 years soil s has outslope position and vegetation progressing towards forest more quickly than the 6 years soil s. In 2 years soil s, the vegetation were sparse, scattered and less dense, among grasses, Eragrostis variabilis, E. puepera, E.atropiodies, E.curvula,E.minor, were found in patches along the outslopes followed by cynodon dactylon, Digitaria microbachne, Echirnochola calona, Dactyloctenium aegyptium, because of less biotic pressure dense patches of the grasses were found. The other vegetation was scarce. The herbaceous vegetation found were 731

6 Echinochloa colone, Andropogan distachya, Brachiaria distachya, Panicum dichotomiflorum and Argemone Mexicana, growing on slopes of s soil. The trees vegetation were almost absent from the 2 years soil s. The tree species of Ziziphus jujube sampling was found on soil s outslopes. At 6 years soil s, the region was densely vegetated with natural vegetation of grasses and sedges of different herbaceous plants. Eragrostis variabilis, E. puepera, E.atropiodies, E.curvula,E.minor, cynodon dactylon, Digitaria microbachne, Echirnochola calona, were dominating grasses found on the outslopes of s area. The other vegetation are were of herbaceous plants Panicum dichotomiflorum Setaria paniculifera, Desmodium triflorum, Mimosa pudica Lantana camara Calotropis procera Argemone Mexicana and Sida acuta and Datura spcemonium. The tree species were also not recorded from the slopes of mines s. In 9 years soil s, the region was densely vegetated with naturally occupied grasses and sedges of herbaceous plant species. The grasses found in the region are Eragrostis variabilis, Eragrostis pacepera, Eragrostis atropiodes, Eragrostis minor, Dactyloctenium aegyptium, Cynodon dactylon, Digitaria microbachne, and Alloteropsis semialata were major dominating grasses in the region. As the aged of soil s increases the number of different species of grasses also varied. At the 8 years soil s the trees species were found are Dalbergia sisso, and Ziziphus jujube dominating in nature. The trees sampling of Accacia nilotica, Acacia auriculiformis, Cassia seamea and Azardirachta indica are also found at the bottom side of soil s. At 16 years soil s, the region was mostly densely populated with grasses, herbaceous and tress of different species. The commonly found grasses were recorded are Eragrostis variabilis, Eragrostis pacepera, Eragrostis atropiodes, Eragrostis minor, Dactyloctenium aegyptium, Cynodon dactylon, Digitaria microbachne, Echirnochola calona, and Alloteropsis semialata. The herbaceous plants growing on the site were Panicum dichotomiflorum, Setaria paniculifera, Desmodium triflorum, Tribulus terrestris, Cyperus rotundus, Alternanthera sessilis, and Evolvulus nummularis are mostly dominating at the site. The trees invading mostly in the region are Dalbergia sisso, Azardirachta indica, Ziziphus jujube, Acacia auriculiformis, Cassia seamea, and Acacia nilotica. Then high species richness in bottom line of mine slopes may be attributed to higher soil moisture and nutrients, greater micro-topographic variation and habitats per unit area. In the 21 years soil s, this is the est naturally reclaimed site in the study area. The soil s are consist of completely deposition of mixed thick alluvial soils ed at the time of pre-mining stage, which is recognized as external at the site. Our results clearly show that the studied 21 years soil are re-vegetated relatively rapidly and, notably, that the vegetation of the soil develops towards similarity with the surrounding vegetation on well-drained mineral ground. At present, after years of succession, the cover and species richness of grasses and associated herbaceous plants and trees species on the soil have reached the level of their surroundings, while establishment of tree species proceeds more slowly. The site is tending towards the successions of tree vegetation. The early forest succession on this external is marked by a predominance of are Dalbergia sisso, Azardirachta indica, Ziziphus jujube, Acacia auriculiformis, Cassia seamea, and Acacia nilotica. These early-successions species, which colonies and established quickly on disturbed areas, grow and begin to ameliorate harsh climatic and soil conditions. They reduce soil temperatures by shading the soil, which allows other species to establish in cooler 732

7 and wetter soil. They also introduce organic matter into the soil by annual leaf inputs in the autumn seasons. Depending upon their ability and success in ameliorating these conditions, favors the vegetation established of different herbaceous and trees species. The herbaceous plants recorded from this site are Cyperus rotundus, Alternanthera sessilis, Evolvulus nummularis, Tephrosia purpera, Mimosa pudica, Lantana camara, Calotropis procera, Argemone Mexicana, Crotalaria retusa, Heliotropium indica, Agrotis stolonifera, Ocimum sanctum, Urena lobata, Sida acuta, Datura spcemonium, and Acacia auriculiforms. Trees species that colonies after early-successional species are those found in adjacent undisturbed forests. The flat top position on mine soil s are still in early-successional stage, being dominated by herbaceous plant species such as Cyperus rotundus, Alternanthera sessilis, Evolvulus nummularis, Tephrosia purpera, Mimosa pudica, Lantana camara, Calotropis procera, Argemone Mexicana, Crotalaria retusa, Heliotropium indica, Agrotis stolonifera, Ocimum sanctum. One reasons for these positions remaining in early successions plant community is primarily due to herbaceous species reseeding themselves annually and providing competition to tree establishment. 5. Conclusions The present study indicates that vegetation in these areas possess around 42 different species of ground flora even after being under continuous biotic and abiotic influence. The ground flora needs to be encouraged. If it is protected and regeneration is encouraged pt will help the tree forms to reappear speedily. Some of the leguminous plants play important role in enriching the soil with nitrogen. Results of this study suggest that coal surface mines in this region can recover a diverse native community fairly quickly, if appropriate site conditions are present. But, it may be much longer than the 21 years of recovery studied before these sites host the entire complement of the local flora. Results of this and other studies suggest a number of management strategies that may facilitate long-term succession on these sites. In this study we have found that, as we precede towards the upper aged soil s there is an increment in vegetation diversity. The diversity in number of different grasses and herbaceous plants replaced by these varieties increased from 2 years to 21 years soil s. As we have found that diversity grasses and associated herbaceous plant species increases but, different aged mines soil s have similarity in plant species, may be due to most of these mine sites are closed to each others that serve as a seed source. This probably one reasons for the large numbers of plant species recorded on naturally grown mine sites. Acknowledgement The authors like to thanks Eastern Coalfield Limited (ECL) for carrying out the study at Eastern coal field, Raniganj. They are also grateful to ISM, Dhanbad for providing research fellowship and necessary support during the study. The authors also thank to HOD, ESE and other technical staff for providing necessary laboratory support. 6. References 1. Cooke, J.A., 1999, mining, Ecosystems of the World 16 - Ecosystems of Disturbed Ground, ed. L.R. Walker, Elsevier, Amsterdam, the Netherlands, pp

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