Summary of the Project Entitled
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SUMMARY OF THE PROJECT ENTITLED “TOURISM INDUCED CHANGES IN THE MEIOFAUNAL DIVERSITY OF CHERAI BEACH – A PROMINENT TOURIST BEACH OF KERALA” By Dr. Priyalakshmi G Dept. of Zoology Bharata Mata College Thrikkakara, Kochi The world’s sandy beaches are iconic assets to society, but escalating threats to these systems pose formidable conservation challenges. During the last decades, recreational activities have been increasing rapidly as people enjoy more leisure time and higher standards of living. Many of these activities are focused on coastal tourism. Tourism has long been considered as a clean industry with almost no negative effects on the environment. Partly due to their barren appearance, sandy beaches have not been regarded as vulnerable to human disturbance (Poulson & Mc Clung, 1999). But beaches are not just piles of sand; they support a range of underappreciated biodiversity. Sandy beaches harbour diverse and abundant assemblage of marine organisms. Besides macrofauna, the sandy beaches are profusely inhabited by microscopic organisms belonging to the lower and higher invertebrate taxa. These organisms that occupy the spaces between the sand grains are called ‘Interstitial Fauna’ or ‘meiofauna’. The diversity of these interstitial organisms that inhabit the interstices of beach sands in the intertidal realm is so astounding that 22 of the known 33 metazoan phyla have their representatives living in this ecosystem. The Gastrotricha, Kinorhyncha, Gnathostomulida, Loricifera, Mystacocarida, Nematoda, Polychaeta, Copepoda, Ostracoda, Turbellaria, Halacaroidea, Hydrozoa, Nemertina, Entoprocta, Gastropoda, Aplacophora, Brachiopoda, Holothuroidea, Tunicata, Priapulida, Sipuncula and many representatives of Rotifera are permanent meiofauna, whereas some organisms like the larvae of macrofauna are a part of meiobenthos, only during their juvenile stages (temporary meiofauna).Thus, benthos represents a major component of the marine environment and plays a vital role in the overall food chain in the sea (Ganesh & Raman, 2007). The impact of tourism does not only include the human trampling on the beach itself, but the whole of activities to maintain it, such as mechanical beach cleaning. Physical disturbance by cleaning activities is already known to cause a decrease or disappearance of macrofauna (Brown & Mc Lachlan, 1990; Mann, 2000). Their effects on the interstitial meiofauna are unclear (Gheskiere et al., 2005). From an Indian perspective, the impact of tourism on the abundance and diversity of meiofauna is an area that still remains almost untouched. India is losing at an alarming rate its vast genetic heritage, the animal wealth of the country, even before these are properly studied and understood. It has become absolutely essential to obtain information on the identity, distribution, interactions and population levels of animal species so that the future developmental programmes (like Tourism) should not be at the cost of our faunal wealth. A better knowledge would draw the attention of a wider scientific public to meiobenthos not only as a scientifically most rewarding animal group, but also as an exemplary and convenient scientific tool to assess pollution. The project on ‘ Tourism induced changes in the meiofaunal diversity of Cherai beach-a prominent tourist beach of Kerala’ was done to achieve the following objectives such as Enumeration of the numerical abundance of aberrant groups of meiofauna of Cherai beach. To study the species diversity of the interstitial fauna. To make an inquiry into the related ecology. To make a comparison of the meiofaunal density and diversity of Cherai beach- 2005, then a pristine beach with the meiofaunal diversity of present day Cherai beach- now a prominent tourist spot of Kerala. Cherai beach (lat.1009 N; long.7602 E), the area of study is a 15 km long stretch, located 30 km north of Kochi with gentle slope and moderate wave action. The sampling stations include the main tourist spot (considered as a polluted region) as Site 1 and Site 2 is located 1.5 Km away from site 1. Cherai beach, now a prominent tourist beach was a pristine beach at the beginning of this century. Bimonthly collections (Aug-Sept; Oct-Nov; Dec-Jan; Feb-Mar; April-May; June-July) and observations were done during the low tide for a period of one year (2011-12). Using all standard protocols, sediment texture and density and diversity of interstitial taxa of sediment samples were worked out and analysed. Statistical analysis using Primer version VI was also done. The sediments at Cherai beach were well sorted or moderately well sorted. More than 50% of the sand fraction was medium sized in all seasons of the year. According to Giere (2009), moderately well sorted medium sand harbours the most diverse meiofauna. Eleven meiofauna groups were recorded during the present study. Nematodes generally constitute the dominant taxa in any habitat. Though nematodes were invarianly present at both stations in different seasons of the year, they did not constitute more than 25% at any of the locations in the present study. Reduction in the meiofaunal density of nematodes at Cherai beach in the present study is surprising. The presence of sensitive or tolerant meiofaunal taxa and nematode genera appears to be particularly informative in highlighting the state of sediment pollution and allows a better assessment of the spatial heterogeneity of environmental disturbance (Moreno et al., 2008).The current investigation revealed the occupancy of gastrotrichs at the dominant position in Cherai followed by turbellarians. Tourism cannot be blamed as a sole factor that can lead to a diminution of meiofaunal taxa since majority of interstitial taxa are well represented in Cherai in the current study even during the monsoon. A comparison of bimonthly collection of total meiofaunal density at station 1 and station 2 proves beyond doubt that unpolluted regions have a better chance of survival for meiofauna than an area which is frequented by tourists from India and abroad A comparison of the meiofaunal density and diversity of Cherai beach, based on studies conducted in 2005-06 and 2011-12 revealed several interesting features. Tourism cannot be taken as a causative factor which can diminish meiofaunal diversity since meiofauna belonging to eleven taxa were represented in the present study in contrast to nine taxa observed in the previous study. The major groups of organisms were found in almost all seasons of the year. But nematofauna, which dominated in the samples collected from Cherai in 2005-06, is outnumbered by Gastrotricha, an aberrant group of meiofaunal organisms. The community structure of nematodes seems to have changed over a period of time where, Rhynchonema and Metepsilonema found in very few numbers in 2005-06 was seen in plenty in the present collection. A general reduction in the density and diversity of nematodes was noticed. Whether their absence during April-May is an impact of climate change or due to the influx of tourists during the summer break is yet to be ascertained. Gastrotrichs were totally absent in Cherai during the monsoon in the previous study whereas, they were well represented in the current study and a marked reduction of these organisms was noticed in April-May. Untimely showers in summer coupled with the absence of proper monsoon in 2011-12 could have led to this unprecedented situation. Several genera found in abundance in the study conducted in 2005-06 is found missing now. Saccocirrus minor, an interstitial polychaete is a classic example for this. Gnathostomulids and foraminiferans are new arrivals in the present study and the disappearance of Cnidaria and Isopoda are conspicuous. Comparison of faunal diversity and density of Cherai in 2005-06 and 2011-12 leads to the conclusion that tourist activities without extensive construction and dredging cannot have a marked effect on the density and diversity of meiofauna, but when coupled with industrial pollution or extensive mechanical beach cleaning activities, can have a negative impact on the interstitial organisms. A change that has occurred in the community structure of interstial organisms over a period of six years cannot be overlooked. The use of modern molecular biology techniques to assess genetic diversity of meiofauna in contaminated vs uncontaminated sediments is a promising avenue for future research. Publications: 1. G. Priyalakshmi. “Changes in the meiofaunal structure of Cherai beach – Tourism induced or impact of climate change? Proceedings of the National Seminar ‘Climate Change Scenario: Threats and potential impacts on ecosystem, (2013): 78-89 2. G. Priyalakshmi and N. R. Menon, “Kerala- an abode of taxonomically challenging permanent meiofauna, Gastrotricha”, Journal of Marine Biological Association of India, Vol.54 (2). (2012): 61-64. ……………………………………. .