Trends1262 in Biosciences 11(7), Print : ISSN 0974-8431,Trends 1262-1269, in Biosciences 2018 11 (7), 2018

An Investigation on the Epidendric Periphyton of Two Mangrove Ecosystems, Asramam and Kandachira of , (Dist.), , S. JISHA*, B. HARI AND A. NEETHU P.G. and Research Department of Zoology, Sree Narayana College, Kollam, Pincode - 691001, Kerala, India *email : [email protected]

ABSTRACT components like substrata, extracellular polymeric The diversity and species composition of epidendric substance, and detritus (Wu, 2017) Periphyton periphyton (periphyton attached to submerged tree limbs communities are a significant contributor to primary and roots, or on other wood surfaces) of areal roots of productivity almost comparable to the contributions Bruguiera cylindrica from two mangrove ecosystems of of phytoplankton in environments that are rich in Ashtamudi backwaters, , Kerala were organic load (Saikia et al., 2013). Periphyton helps in studied through fortnight samplings for a period of three the nutrient turnover and transfers of energy to months. Qualitative as well as quantitative estimation of the abundance of epidendric periphyton community from successive trophic levels and thus maintains the food both Kandachira (Station 1) and Asramam (Station 2) were web (Saikia, 2011). They also contribute the essential carried out. Systematic positions of periphyton community oxygen to the polluted water bodies and act as were found out. Sampling from Kandachira revealed that cleansers by removing organic contaminants. Class Bacillariophyceae (62.22%) dominated among 45 Planktonic algae enhances the productivity and they species collected and identified. From Asramam, 36 species also act as good indicators of water quality (Palmer, were identified, of which 58.33% comprised of Class Bacillariophyceae. Other classes collected and identified 1980; Odum, 1997). Periphyton community range from Ashtamudi Lake were Coscinodiscophyceae, their habitats from almost all available substrata, natural Zygnematophyceae, Euglenophyceae, Cyanophyceae and and to some artificial substrata. Among them, roots of Chlorophyceae. Atmospheric temperature, water quality mangrove provide an ideal place of colonization and parameters such as temperature, pH, salinity, turbidity, also present a unique array of both micro-floral and dissolved oxygen (DO), biological oxygen demand (BOD), faunal groups. Mangroves are the most productive acidity, and total alkalinity were analysed on a biweekly basis during the period of study. Soil pH and soil moisture buffer zone that can tolerate wide range of salinity content were estimated. Soil texture at both stations were fluctuations; also contribute to nutritive sediments analysed and were dominated by Silt. The results of the which offers huge primary production which indirectly comparative analysis showed that Asramam seemed to be promotes secondary production (Bardarudeen et al., more polluted with relatively high BOD levels and 1996). represented by a good number of pollution indicator species, especially the presence of Cyanophyceans. The Periphyton communities can reflect the health study revealed the pollution status of the ecosystems and status and nutrient availability in aquatic ecosystems. the chances of using periphyton as good ecological Their assessment may help to estimate the extent of indicators. pollution. Presence and quantity of some species of Keywords Periphyton, epidendric algae, Soil diatoms may give accurate information on the stability parameters, Hydrological parameters, and degree of pollution of aquatic ecosystems (Kiran Kerala, India et al., 2006). Degree of variations in species composition and community structure of periphyton The term Periphyton encompasses a wide variety may be due to the constantly altering ecosystem and of algae, bacteria, micro-invertebrates found intimately it can be regarded as the ecological impact on them. associated with submerged substrata (Stevenson, However, magnitude of impact may vary according 1998). Periphytic biofilms are an integrated micro- to the habitat and the available substratum. Diversity system composed of biotic components which are seen studies on periphyton community from mangroves are in aquatic ecosystems. They composed of algae, fungi, undergoing around the world. Studies on periphyton bacteria, protozoa and metazoan and abiotic JISHA et al., An Investigation on the Epidendric Periphyton of Two Mangrove Ecosystems, Asramam and Kandachira 1263

Table 1. Systematic positions of epidendric periphytic algae collected and identified from stations 1 & 2 during the study period Sl.No. Periphyton Class Order Family 1 Achnanthes xigua Bacillariophyceae Achnanthales Achnanthaceae 2 Achnanthes sp. Bacillariophyceae Achnanthales Achnanthaceae 3 Achnanthidium minutissimum Bacillariophyceae Achnanthales Achnanthidiaceae 4 Amphora sp. Bacillariophyceae Thalassiophysales Catenulaceae 5 Closterium sp. Zygnematophyceae Desmidiales Closteriaceae 6 Cocconeis pediculus Bacillariophyceae Achnanthales Cocconeidaceae 7 Cocconeis placentula Bacillariophyceae Achnanthales Cocconeidaceae 8 Cocconeis sp. Bacillariophyceae Achnanthales Cocconeidaceae 9 Coscinodiscus granii Coscinodiscophyceae Coscinodiscales Coscinodiscaeceae 10 Coscinodiscus sp. Coscinodiscophyceae Coscinodiscales Coscinodiscaecae 11 Cosmarium sp. Zygnematophyceae Zygnematales Desmidiaceae 12 Cyclotella meneghiniana Bacillariophyceae Pennales Naviculoideae 13 Cyclotella sp. Bacillariophyceae Pennales Naviculoideae 14 Cymbella sp. Bacillariophyceae Cymbellales Cymbellaeceae 15 Diploneis sp. Bacillariophyceae Naviculales Diploneidaceae 16 Encyonema sp. Bacillariophyceae Cymbellales Cymbellaceae 17 Euglena acus Euglenophyceae Euglenales Euglenaceae 18 Fragilaria sp. Bacillariophyceae Pennales Fragilariaceae 19 Frustulia sp. Bacillariophyceae Naviculales Amphipleuraceae 20 Gleocapsa sp. Cyanophyceae Chroococcales Chroococcaceae 21 Gomphonema sp. Bacillariophyceae Cymbellales Gomphonemataceae 22 Gyrosigma sp. Bacillariophyceae Naviculales Pleurosigmataceae 23 Lyngbya sp. Cyanophyceae Nostocales Oscillatoriaceae 24 Melosira sp. Bacillariophyceae Melosirales Melosiraceae 25 Merismopedia sp. Cyanophyceae Chroococcales Merismopedioideae 26 Microspora sp. Chlorophyceae Microsporales Microsporaceae 27 Navicula gregaria Bacillariophyceae Naviculales Naviculaceae 28 Navicula transitans Bacillariophyceae Naviculales Naviculaceae 29 Navicula sp. Bacillariophyceae Naviculales Naviculaceae 30 Nitzschia palea Bacillariophyceae Bacillariales Bacillariaceae 31 Nitzschia gracilis Bacillariophyceae Bacillariales Bacillariaceae 32 Nitzschia obtusa Bacillariophyceae Bacillariales Bacillariaceae 33 Nitzschia recta Bacillariophyceae Bacillariales Bacillariaceae 34 Nitzschia reversa Bacillariophyceae Bacillariales Bacillariaceae 35 Nitzschia sigma Bacillariophyceae Bacillariales Bacillariaceae 36 Nitzschia sp. Bacillariophyceae Bacillariales Bacillariaceae 37 Nostoc sp. Cyanophyceae Nostocales Nostocaceae 38 Oscillatoria sancta Cyanophyceae Oscillatoriales Oscillatoriaceae 39 Oscillatoria limosa Cyanophyceae Oscillatoriales Oscillatoriaceae 40 Oscillatoria princeps Cyanophyceae Oscillatoriales Oscillatoriaceae

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Sl.No. Periphyton Class Order Family 41 Oscillatoria sp. Cyanophyceae Oscillatoriales Oscillatoriaceae 42 Oscillatoria tenuis Cyanophyceae Oscillatoriales Oscillatoriaceae 43 Phormidium sp. Cyanophyceae Nostocales Oscillatoriaceae 44 Pinnularia conica Bacillariophyceae Naviculales Pinnulariaceae 45 Pinnularia sp. Bacillariophyceae Naviculales Pinnulariaceae 46 Pleurosigma sp. Bacillariophyceae Naviculales Pleurosigmataceae 47 Spirogyra sp. Zygnematophyceae Zygnematales Zygnemataceae 48 Spirulina major Cyanophyceae Oscillatoriales Oscillatoriaceae 49 Surirella sp. Bacillariophyceae Surirellales Surirellaceae 50 Synedra sp. Bacillariophyceae Fragilariales Fragilariales 51 Zygnema sp. Zygnematophyceae Zygnematales Zygnemataceae diversity in the aquatic ecosystems of Kerala especially Methods Ashtamudi backwaters are scanty. In this context, Qualitative and quantitative estimation of the present study is an attempt to understand the epidendric periphyton from the mangrove, Bruguiera diversity of epidendric periphyton communities in cylindrica were carried out from the samples of both Kandachira and Asramam mangroves and also the stations. Triplicate samples of periphyton, water and water and soil quality parameters. soil were collected fortnightly from both stations for a MATERIALS AND METHODS period of three months and brought to the laboratory for further analysis. Study Sites Qualitative as well as quantitative estimation of An Ashtamudi backwater is known as “Gate the abundance of epidendric periphyton community way of backwaters” and is the second largest wetland from both Kandachira (Station 1) and Asramam ecosystem in Kerala. It is included in the list of (Station 2) were carried out using standard procedures wetlands of international importance. The backwater (Biggs and Kilroy, 1994). The roots of mangroves of supports patches of mangrove ecosystems in sheltered length 10cm were sampled out and the periphytic algae regions. Ashtamudi backwaters support a good were scrapped out and preserved in 4% formalin for number of fishes, birds, crustaceans and molluscans. further analysis. The samples were qualitatively and All the eight arms of the Ashtamudi are seriously quantitatively analysed with the help of a light threatened by various anthropogenic activities. Two microscope. Systematic positions of periphyton stations with patches of mangroves, Kandachira and community were found out and analysed using Asramam, which lie on Ashtamudi backwaters, were standard keys and identifying manuals (Biggs and selected for the periphyton study. Station 1,Kandachira Kilroy, 1994; Newell and Newell, 1988 and Santhanam mangrove ecosystem is the southern part of the et al., 1987). 0 0 0 Ashtamudi estuary (8 45`-9 28`N and 76 28`- Temperature was measured using a precision 0 0 0 77 17`E). Kandachira (8.5617376 N and 76.3646332 mercury thermometer; salinity using hand E) is one of the eight water channels of Ashtamudi is refractometer; water pH and conductivity were nourished by mangroves. Station 2,Asramam measured by a Multi Parameter Instrument; turbidity mangroves is situated near the K.S.R.T.C. bus station using Nephalo turbidity meter; acidity and alkalinity 0 0 (8.895888 N and 76.5920927 E). The region is blessed by acid-base titration and dissolved oxygen (DO) and with the Ashtamudi Lake but its water quality is biochemical oxygen demand (BOD) were estimated deteriorating day by day. The site provides warning by Winkler’s method. These were estimated using signs of pollution and some regions are very much standard guidelines (APHA, 1989). Sediment samples similar to solid and liquid waste dumping yards. were collected from two stations using a locally JISHA et al., An Investigation on the Epidendric Periphyton of Two Mangrove Ecosystems, Asramam and Kandachira 1265

Table 2. Comparison of epidendric periphyton collected and identified from stations 1 & 2 during the study period

Sl. No. Periphyton Station 1 Station 2 1 Achnanthes xigua + + 2 Achnanthes sp. + + 3 Achnanthidium minutissimum + - 4 Amphora sp. + + 5 Closterium sp. + + 6 Cocconeis pediculus - + 7 Cocconeis placentula + + 8 Cocconeis sp. - + 9 Coscinodiscus granii + - 10 Coscinodiscus sp. + + 11 Cosmarium sp. + - 12 Cyclotella meneghiniana + - 13 Cyclotella sp. + + 14 Cymbella sp. + + 15 Diploneis sp. + + 16 Encyonema sp. - + 17 Euglena acus + + 18 Fragilaria sp. - + 19 Frustulia sp. + - 20 Gleocapsa sp. + + 21 Gomphonema sp. + - 22 Gyrosigma sp. + + 23 Lyngbya sp. + + 24 Melosira sp. + + 25 Merismopedia sp. + - 26 Microspora sp. + + 27 Navicula gregaria + + 28 Navicula transitans + - 29 Navicula sp. + + 30 Nitzschia palea + + 31 Nitzschia gracilis + - 32 Nitzschia obtusa + - 33 Nitzschia recta + - 34 Nitzschia reversa + + 35 Nitzschia sigma + - 36 Nitzschia sp. - + 37 Nostoc sp. + - 38 Oscillatoria sancta - + 39 Oscillatoria limosa - + 40 Oscillatoria princeps - +

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Sl. No. Periphyton Station 1 Station 2 41 Oscillatoria sp. + + 42 Oscillatoria tenuis + + 43 Phormidium sp. + + 44 Pinnularia conica + + 45 Pinnularia sp. + + 46 Pleurosigma sp. + + 47 Spirogyra sp. + - 48 Spirulina major + + 49 Surirella sp. - + 50 Synedra sp. + + 51 Zygnema sp. + + ‘+’ indicates presence and ‘–‘ indicates absence

designed corer and were treated based on the were commonly occurred in both stations. Nasser parameters aimed. For soil texture studies, sieve and Sureshkumar (2014) studied the habitat-wise analysis method was followed. Soil pH and soil variation in periphytic-microalgal assemblages in the moisture content were estimated using standard Vazhachal forest division of Chalakkudy river basin. procedure (Verma and Agarwal, 1998). The number They reported 97 species of micro algae and stated of periphytons, air temperature and water parameters that the periphytic algal composition can vary collected from two sampling stations were statistically according to different habitats. Navicula sp. was analysed using t’-test (Snedecor and Cochran, 1968). numerically most abundant species at Kandachira and Oscillatoria sp. was most dominant at Asramam. RESULTS & DISCUSSION Pinnularia sp., Achnanthes sp., Melosira sp.,and A total of 51 species of epidendric periphytic Cymbella sp.and. were the other dominant members. algae were collected and identified from the Synedra sp., Euglena sp., and Diploneis sp. were mangroves of Ashtamudi backwaters during the study numerically very low throughout the samplings in both period. Of which 45 species were from Station 1, stations. 2nd, 3rd and 4th samplings showed maximum Kandachira and 36 species from Station 2, Asramam. number of species while 6 th sampling showed Based on the identification, a checklist of periphytic comparatively less amount of periphyton. Onset of algae was prepared. Systematic positions of periphytic monsoon may have an impact in the reduction of algae were found out and displayed in Table 1. periphyton. Sampling from Kandachira revealed that Comparative study was done based on the Class Bacillariophyceae (62.22%) dominated among availability of periphyton from stations 1 & 2 and the 45 species collected and identified. From Asramam data was tabulated (Table 2). They consisted of 6 36 species were identified and of which, 58.33% classes, of which Class Bacillariophyceae dominated comprised of Class Bacillariophyceae. Other classes in both stations (Kandachira- 62.22% and Asramam- included were Coscinodiscophyceae (Station 1- 4.44%, 58.33%). Apart from it, Coscinodiscophyceae (Station Station 2- 5.55%), Zygnematophyceae (Station 1- 1- 4.4%, Station 2- 5.6%),), Zygnematophyceae 11.11%, Station 2- 5.55%), Euglenophyceae (Station (Station 1- 11.1%, Station 2- 5.6%), Euglenophyceae 1-2.22%, Station 2-2.77%), Cyanophyceae (Station 1- (Station 1-2.2%, Station 2-2.8%), Cyanophyceae 17.77%, Station 2- 25%) and Chlorophyceae (Station (Station 1- 17.8%, Station 2- 25%) and Chlorophyceae 1- 2.22%, Station 2- 2.77%). (Station 1- 2.2%, Station 2- 2.8%) were recorded. The result of the analysis of water quality A quantitative study of epidendric periphyton parameters is presented in Table 3. The t- test showed from both stations showed distinct variations in the that there exists no significant variations (P>0.05) in number and diversity of species (Fig. 1). 27 species air temperature, water temperature, pH, salinity, acidity, JISHA et al., An Investigation on the Epidendric Periphyton of Two Mangrove Ecosystems, Asramam and Kandachira 1267

Fig. 1. Number of periphyton on mangrove roots from two sampling stations phenolphthalein alkalinity of two sampling stations. of Anabaena species also denotes the organic load However, turbidity, DO, BOD, methyl orange alkalinity of a particular aquatic ecosystem. and total alkalinity showed significant variations Rafia et al. (2013) showed the dominance of (P<0.05) between stations. Bacillariophycean members among other periphyton The values of BOD and DO showed polluted communities. They also reported the prevalence of nature of the aquatic body in Station 2 relative to Station some species like Closterium sp., Zygnema sp., 1. Cyanophyceaens dominated on the roots from Amphora sp., Cymbellas p., Epithemia sp., Station 2. In polluted Asramam mangroves, the Fragilaria sp., Navicula sp., Synedra sp., Lyngbya filamentous algae showed its prominence in number sp. and Phormidium sp. This is in accordance with which may be due to rapid nutrient enrichment, low the present study also. The dominance of Class salinity, low DO, high BOD and high Turbidity. Bacillariophyceae was also reported by Ashok et al. Oscillatotria sp. was the most dominant periphytic (2014) in similar systems. Sarika et al. (2015) also algae from Asramam.Oscillatora sp., Spirulina sp., reported the prevalence of Oscillatoriales (O. sancta, Lyngbya sp.and Gleocapsa sp. were the most O. limosa, O. subbrevis, O. vizagapatensis and O. dominant Cyanophyceans (Table 4). Significant nigro-viridis)in polluted aquatic systems.In this study variations (P<0.05) in the number of Cyanophyceans also, Oscillatorians dominated in Station 2 and points were found among Station 1 & 2 (Table 4). The out heavy organic load in the system. These results Dhanya et al. (2015) carried out extensive investigation strongly reflect the anthropogenic disturbances in the on the Cyanobacteria in Kuttanadu Paddy Wetlands, Ashtamudi backwaters especially Asramam region. Kerala. They suggested that the dominance of Organic load had worsened the condition and has been Oscillatoriales may be due to high nutrient status of indicated by the growth of filamentous algae like paddy fields. They also reported the presence of Oscillatoria sp., Lyngbya sp., Phormidium sp. etc. Phormidium sp. and Leptolyngbya sp. Similar results The low DO and high BOD values are indicators of were obtained in the present study also. Hence, pollution. The Turbidity values in some of the occurrence of Osillatoria sp., Phormidium sp. and samplings have reached up to 202 NTU. Mathew Lyngbya species can be regarded as biological and Nair (1980) points out that low salinity favours indicators of high nutrient status and reveals the the algal growth. The onset of monsoon contributes pollution status of Station 2 (Asramam mangroves). to low salinity level and rapid enrichment of organic According to Jafari and Gunale (2006), the presence pollutants which may accelerate the growth of 1268 Trends in Biosciences 11 (7), 2018

Table 3. Water quality parameters of two sampling stations

t –test Water Quality Parameters Station 1# Station 2# Significance Water temperature (oC) 30.0+1.6 30.5+1.6 NS pH 8.0+0.4 7.5+0.3 NS Salinity (ppt) 26.8+8.7 27.0+13.3 NS Turbidity (NTU) 62.0+49.9 153.7+74.5 * Dissolved Oxygen (mg L-1) 6.1+1.4 2.7+2.7 * Biological Oxygen Demand 6.7+2.7 27.2+13.8 * Acidity (mg L-1) 30.2+49.7 25.2+17.7 NS Phenolphthalein Alkalinity (mg L-1) 70.0+62.9 33.3+53.2 NS Methyl orange Alkalinity (mg L-1) 826.7+32.7 1913.7+970.7 * Total Alkalinity (mg L-1) 896.7+79.4 1946.7+949.6 * # Mean +STD NS - Not significant (P>0.05) * P<0.05

(phytoplankton) algal species. In the present study identified from the periphyton community of Station 1 salinity value decreased with the advance of monsoon (Kandachira mangroves). These included barnacles, season. nauplius, crustaceans and rotifers. Soil samples The present study revealed the presence of collected from the bottom of two stations were also Oscillatoria, Phormidium and Lyngbya species in analysed. Soil pH (Station 1- 5.5, Station 2- 6) and mangrove habitats and similar observations were soil moisture content (Station 1- 5.2%, Station 2- 6.1%), made by Nedumaran et al., (2008). Sebastian and were estimated for the period of study. Soil texture at Ammini (2013) studied the diversity of filamentous both stations were analysed and both were dominated algal species and points out that the presence of certain by Silt. 41.6% silt, 26.6% clay, 10.6% fine sand and algae can indicate the pollution status in the lakes. 21.2% coarse sand were recorded from the soil The authors inferring from their studies concluded that samples of Station 1 and 51.6% silt, 13.7% clay, 6.1% Spirogyra sp. was the most widely distributed followed fine sand and 28.6% coarse sand from Station 2. by Oscillatoria rubescens and was responsible for Adverse anthropogenic effects, oil spills from the bloom formation. In the present study, Oscillatoria fishing boats and industries are considered to be the sp. was greater which may responsible for bloom and important reasons behind the deterioration of scum formation in Station 2, Asramam. Along with backwaters in Kerala. The municipal waste and solid microfloral communities, some faunal groups were also waste contamination has developed foul smell in

Table 4. Presence various species of Cynobacteria (No. of cell L-1 ) in the areal roots of mangrove tree, Bruguiera cylindrica (Mean of six samplings) from two stations

Sampling Stations Cynobacteria t –test Significance Kandachira Asramam Oscillatoria sp. 96111 584444 * Spirulina sp. 5556 17778 * Lyngbya sp. 78889 254445 * Gleocapsa sp. 0 17778 * NS - Not significant (P>0.05 ) * P<0.05

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Received on 08-02-2018 Accepted on 11-02-2018