International Research Journal of Biological Sciences ___________________________________ ISSN 2278-3202Vol. 2(7), 1-5, July (2013) Int. Res. J. Biological Sci. International Science Congress Association 1 Wetland Plant, Nelumbo nucifera Gaertn. (Lotus) serving as a Habitat for MacroinvertebratesBangotra K., Kaur B. and Andotra S. Department of Zoology, University of Jammu, Jammu, J&K 180006, INDIA Available online at: www.isca.in Received 14th March 2013, revised 24th April 2013, accepted 23rd May 2013Abstract The present communication deals with the study of association of macroinvertebrate fauna with a wetland plant, Nelumbo nucifera Gaertn. (Lotus) during the period extending from July, 2010 to June, 2011. The present study revealed association of 3 phyla with Nelumbo nucifera viz., Annelida (18.34%), Arthropoda (53.32%) and Mollusca (28.52%) constituting a total of 2388 organisms/m. The macroinvertebrates were found to utilize Nelumbo vegetation as their habitat as different stages of their life cycle viz., eggs, larvae, pupae and adults were observed to show an intimate relationship with the plant. Statistical analysis was done and Physico-chemical parameters were also analysed which showed well marked seasonal fluctuations.Keywords: Macroinvertebrate, Nelumbo nucifera Gaertn., Phytophilous, Statistical indices Introduction One of the most important and attractive wetland plant species in India is the ‘Sacred Lotus’, Nelumbo nucifera Gaertn. which grows widely in temperate, sub-temperate, subtropical and tropical regions in South-East Asia. The genus “Nelumbo” constitutes the plants exhibiting enormous phenotypic diversity including racial variants differing in shapes, sizes and shades. It is known to possess a great medicinal and food value. Besides this, it also acts as a natural water filter and home/shelter for wildlife. In general, the macrophytes represent a “Phytal habitat”, “Mesohabitat” and “Functional habitat”4 many organisms. Habitat conditions like the distribution and species composition of macrophytes and associated epiphytic algae are important in structuring the community of phytophilous invertebrates5,6,7. Macrophytes belonging to family Nympheaceae are rich in chemical compounds8,9, which might provide invertebrates (insects) with unique chemical cues to maintain specialized associations. Despite knowing such beneficial aspects about Nelumbo nucifera , its ecological relationship with macroinvertebrate fauna and its effects on the ecology of aquatic ecosystems has not gained much attention of biologists and research workers in India, particularly in Jammu. So, the present research was undertaken to throw light on the impact of N. nucifera on the aquatic ecology and its association with the macroinvertebrate fauna of a shallow pond in Jammu. Material and Methods Study area: The present study was conducted in shallow pond of Jammu showing prolific growth of macrophytes such as N. nucifera, Marselia quardifolia, Azolla pinnata, Lemna sp. and Ceratophyllum demersum. Due to the presence of thick vegetation cover, the pond bottom is rich in organic matter and serves as a suitable niche for many invertebrates and vertebrates. Field and Lab Studies: For the analysis of physico-chemical parameters, the water sample was collected from the littoral regions of the stream. pH was measured using portable pH meter (Hanna model), dissolved oxygen, free carbon dioxide, carbonates and bicarbonates, chloride, calcium and magnesium were measured by following procedure recommended by A.P.H.A.10. Physical parameters like air and water temperature, depth, transparency and speed were also measured at the study sites. Collection of N. nucifera was done from the littoral areas of the stream by quadrant method using Ekman’s dredge having an area of 232 cm. The macrophytes so collected were put into separate polythene bags and brought to the laboratory for further studies. The plants were washed in the laboratory and the associated macroinvertebrates were isolated using sieve no. 40 with 256 meshes/cm and preserved in 4% formation and 70% ethyl alcohol. Preserved samples of macrobenthic invertebrates were identified with the help of Ward, H.B. and Whipple, G.C.11, Pennak, R.W.12, Tonapi, G.T.13 and Adoni, A.D.14. The egg masses of the macroinvertebrates were separately counted and preserved in 4% formalin. Statistical analysis of the macroinvertebrate fauna associated with E. crassipes was done by calculating Margalef’s Richness index (), Shannon-Weiner index (), Simpson’s Dominance index (D) and Equitability index (J). Results and Discussion The pond surveyed in the present study faces many stresses of anthropogenic origin which affect the distribution of its International Research Journal of Biological Sciences ________________________________________________ ISSN 2278-3202 Vol. 2(7), 1-5, July (2013) Int. Res. J. Biological Sci. International Science Congress Association 2 inhabitants as the sensitive individuals are not able to sustain alterations in their habitat and may not survive and some get elimnated15. Many macroinvertebrates show phytophily which may be mechanism devised for achieving better conditions for their survival. A total of 2388 organisms/m2 from 23 taxa of macrobenthic invertebrates belonging to 3 phyla were viz., Annelida (18.34%), Arthropoda (53.32%) and Mollusca (28.52%) were obtained from N. nucifera during the present investigation (table 1). In phylum Annelida, 5 taxa were recorded in association with N. nucifera. These included Tubifex tubifex and Lumbricillus sp. which were obtained from the roots of Nelumbo whereas Naidids (Dero digitata, D. furcatus and Chaetogaster sp.) were recorded from its roots as well as the expanded leaf lamina. Occurance of D. liminosa and Chaetogaster limnaei constituting 0.45% of phytophilous fauna of floating leaved macrophytes has been documented by Arimoro, F.O., Ikomi, R.B. and Efemuna, E.16. Naidu, K.V., Kalpana, K. and Kumar, S.17 and Poi de Neiff, A. and Carignam, R.18 also recorded Dero and Aulophorous as the most common faunal elements associated with macrophytes. Further, according to Bouchard, R.W.Jr.19, Naidid oligochaetes increase their number in response to organic pollution. The presence of Naidids with N. nucifera in the present study suggests that the plant might be providing nutrient rich environment which favours the growth of these worms. In a study conducted by Parikh A. N. and Mankodi P.C.20 higher planktonic production, macrophytic decay and shallowing of pond due to evaporation subsequently increased the nutrient (nitrates) concentration. Arthropods constituted the taxonomically and numerically richest phylum associated with N. nucifera as revealed from (table 1) which included individuals from class Increase icta and Arachnida. Arachnida added 1.44% to the total phytophilous fauna associated with N. nucifera with Piona sp. and Hydrodroma sp. as its representatives. Arimoro, F.O., Ikomi, R.B. and Efemuna, E.16 also reported Hydrarachnida from floating plants (Nymphea lotus). They suggested that the mites used the leaves for constructing their webs for seeking shelter and feeding purposes. In addition to this, spawns of mites were also observed from the underside of lamina of N. nucifera (figure 1) in the present work. The spawns were composed essentially of roughly sphearical gelatinous matrices with eggs embedded in them. Similar observations were made by Uchida, T.21 who recorded clumps of eggs of Piona obturbans from Cladophorasp. whereas spawn of Acercus ornatus Arrhenurus and Limnesia fulgida from leaves of Elodea and walls of aquarium. From this association, it appears that mites may be deriving nutrients, protection and shelter from predators by using N. nucifera in this manner. The present studies revealed that the phytophilous entomofauna contributed 51.88% to the plant associated fauna. The insects included individuals from 3 orders viz., Coleoptera (16.26%), Hemiptera (6.21%) and Diptera (29.39%) contributing 51.88% to the total fauna obtained from Nelumbo (table 2). Interestingly, larvae and air filled pupal cases of Donacia sp. (Order - Coleoptera; Family Chrysomelidae) were also recovered from the roots of N. nucifera (figure 2-4). The association of Donacia palmate with Nelumbo lutea has already been reported by Whiteman, N. and Sites, R.W.22. Adult Donacia are feeders of Nelumbo leaves. Donacia females are known to lay eggs on the leaves of water lilies from which larvae hatch out and traverse through the elongated petioles to N. nucifera to reach its roots where they feed and respire. The larvae were found to possess specialized respiratory structures at the posterior end of their body (figure 5) which the larvae insert into the roots of Nelumbo for respiration. Phytophilous Hemiptera recorded from Nelumbo were represented by three taxa belonging to family Pleidae, Belostomalidae and Notonectidae. Among the Dipterans, Chironomids (Grazers) were the most abundant functional group (among the dipterans) found encased in muddy cases (tunnel shaped) formed over the lamina. Increased population of chironomids was recorded with the decomposition of Nelumbo crop which may be attributed to the increased palatability and enhanced digestibility of decomposing plants as compared to their freshly blooming counterparts. The decomposing plants leach out nutrients and offer an organically rich diet to the grazers. Similar findings have been reported by da Silva, F.L., Oliveira, H.R.N., Escarpinati, S.C., Fonseca - Gessner, A.A. and Paula, M.C.D.23who advocated that live aquatic macrophytes are not good food resource for majority of members of aquatic macroinvertebrates since they are difficult to digest. Mollusca was reported to be the second most abundant phylum contributing to 28.32% of the phytophilous fauna of N. nuciferaand was represented solely by Gyraulus sp. The expanded lamina was found to be an ideal substrate for the growth of epiphytic algae on which these grazers feed causing its skeletonization (figure 6). Not only adult Gyraulus but its gelatinous egg masses as well as young crop (figure 7-8) was also reported from the underside of Nelumbo leaves touching the surface of water. The incidence of oviposition of molluscs over the Nelumbo leaves indicates it acts as a suitable site for oviposition. It works as a potential mechanism for avoiding hypoxia by fulfilling their need of a well oxygenated moist environment even when they are laid in clusters of many. The present finding has been further supported by Woods, H.A. and Podolsky, R.D.24while examining the effect of light level and associated photosynthetic organisms on the distribution of oxygen inside the gelatinous egg masses of four temperate gastropod species concluded that photosynthesis by macrophytes can drive large changes in internal oxygen profiles of the egg masses deposited on them. International Research Journal of Biological Sciences ________________________________________________ ISSN 2278-3202 Vol. 2(7), 1-5, July (2013) Int. Res. J. Biological Sci. International Science Congress Association 3 Table-1 Annual Percent Contribution of different Classes from Individual Group of phytophilous macroinvertebrates recorded from Nelumbo nucifera (July 2010 to June 2011) Phylum Classes Nelumbo nucifera Number of Individuals (n/m) Annual Percent Contribution Annelida Oligochaeta 438 18.34 Total 438 18.34 Arthropoda Arachnida 34.5 1.44 Insecta 1239 51.88 Total 1264.5 53.32 Mollusca Gastropoda 676.5 28.32 Total 676.5 28.32 Total ORG./m 2388 Table-2 Annual Percent Contribution of different orders of Class-Insecta to the phyophilous fauna of N. nuciferaOrders Number of Individuals (n/m) Annual Percent Contribution Coleoptera 388.5 16.26 Diptera 702 29.39 Hemiptera 148.5 6.21 Total 1239 51.88 Table-3 Values of various statistical indices applied on the phytophilous macroinvertebrates recorded from N. nuciferaShannon–Weiner diversity index (   0.947 – 1.987 Simpson’s Dominance index (D)0.171 - 0.520 Equitability index (J) 0.565 – 0.964 Margalef’s Richness index (   0.505 – 2.011 Table-4 Range of some physico-chemical parameters of the pond (July, 2010 to June, 2011)Range Water Temp. Depth DO pHFCOCO2-(mg/l)HCO Ca2+ Mg2+ClPO2- Units ( C)(cm)(mg/l)nil (mg/l)(mg/l)(mg/l)(mg/l)(mg/l)(mg/l)(mg/l) Minima 16.9 12.0 2.4 6.5 0.0 0.0 183.0 8.82 12.15 15.96 0.0 Maxima 30.0 31.7 15.2 8.4 48.0 36.0 463.6 32.88 31.59 77.84 1.75 ConclusionCurrent research paper highlights the ecological importance of N. nucifera with special reference to its role as an appropriate habitat for phytophilic fauna. The study shows varied phytofauna associated with this wetland plant including annelids, arthropods and molluscs among which arthropods, particularly, insects showed greatest affinity towards it. The associated fauna was observed to utilise this plant for a wide array of life activities like feeding/ grazing, gliding, oviposition, pupation etc. It is clear from this work that N. nucifera is an asset in the fresh water ecosystems as it promotes species density and diversity.