INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCES Volume 2, No 4, Copyright 2010 All rights reserved Integrated Publishing Association

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1 INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCES Volume 2, No 4, 2012 Copyright 2010 All rights reserved Integrated Publishing Association Research article ISSN Phytosociological analysis of riparian tree species of Alakyam stream; Pariyaram, Kerala, India Department of Environmental Studies, Kannur University, Edat Post, Payyanur, Kannur, South India manu.alathur@yahoo.com doi: /ijes ABSTRACT Present study describes the phytosociological analysis of riparian tree species of a non perennial Alakyam stream located at Pariyaram, Kannur District of Kerala. The vegetation of this stream bank consists of variety of herbs, shrubs, climbers and trees. Most of the species in this area belongs to either endemic or RET categories (Rare, Endangered and Threatened Species). Phytosociological data of tree species of such type of vegetated area is scanty. Stratified random sampling method was adopted for quantification of the vegetation. A quadrate having 10M X10M size was adopted for sampling. A total of 25 such sampling plots were laid out to sampling approximately 10% of the study area. A total of 63 species of trees having GBH more than 15 cm size belonging to 37 families were recorded from 25 sample plots. The total density of tree species in the study area is 406.8/ha. The species having highest density is Hopea ponga (55.1/ ha). Hopea ponga is the most frequent species with a value of 70%. The species with maximum importance value index is Hopea ponga (17.22). In terms of Ecological status, 73% species of encountered trees are common. About 27% (Endemic & Common = 17% + Endemic RET =10) category of the flora (Trees) present in the study area is endemic to Western Ghats. About 10% of the tree species belongs to RET category (Endemic & Endangered = 5%, Endemic & Rare = 2% and Endemic & Threatened = 3%). This study reveals the status of diversity of riparian tree species. The Phytosociological results indicate the need of adoption of a strong ecosystem management strategy particularly for the rare, endemic flora of this region. The riparian in order to protect them, conservation of the Alakyam stream is necessary. Keywords: Phytosociology, Riparian species, Alakyam, Ecology, Hopea ponga 1. Introduction Monitoring of plant population is an easy way for understanding the environmental conditions of an area (Niemi and MC Donald, 2004). Over exploitation of biodiversity leads to extinction of many species from the earth face (Grove, 1995). Rapid extinction of species is one of the most serious ecological problems facing the humanity today. Ecological status of an area is determined by assessing the biodiversity of a region, the environmental conditions prevailing there and their interactions. It represents the overall health and sensitivity of an ecosystem. Ecological status assessment and documentation becomes essential for arriving at an appropriate conservation and sustainable management strategies. This assessment is done by evaluating the components along with its functional abilities of an ecosystem. This includes the assessment of species diversity, frequency and Received on March 2012 Published on May

2 their Importance Value Index and threat of their habitat by anthropogenic activities which may alter the physical, chemical and biological integrity of the system. Solid wastes especially non degradable wastes have been turned into a major cause of depletion of fresh water ecosystems (Suter, 1993). Fragmentation of riparian ecosystem has been described as the single greatest threat to global biological diversity (Laurance, 2002). Changes in land use and Resource utilization pattern leads to the mass extinction of many species including wetland diversity (Ksornkoar, 1993). Climatic factors like average annual rainfall and the anthropogenic disturbances also influence the distribution of diversity especially in tropical countries (Hill, 2001). Conservation of habitat and ecosystem by means of protected area networks, ecological restoration and sustainable resource management is very important for biodiversity conservation (Angermeier, 2000). Besides global categories on species, there is local criteria should also be needed for conservation (Palmer, 1997). Alakyam Stream is one of the major water body in which the local people depend for various purposes. The riparian vegetation of the stream bank especially the tree species and the Alakyam stream are found to be interact each other. So an attempt has been made to assess the ecological status of riparian tree species of Alakyam stream banks of Pariyaram Medical College Area of Kannur District by considering the primary analysis of phytosociological aspects of riparian tree species. 2. Materials and methods 2.1. Study Area Alakyam Stream is situated in three Panchayaths such as Kadannappalli, Panapuzha and Cheruthazham of Kannur District of Kerala State. It starts from Pariyaram and ends in Vilayankodu. It lies between North latitude and East longitude. Total length of the stream with riparian vegetation is 8 km. Altitude of the study area is 50 meters from Mean Sea Level (MSL). Some pockets of the study area are covered by rocks. The main geological formation is latterite soil. The climate is generally warm type. The annual rainfall ranges between mm with south west monsoon rains during June-September also contributing a major portion of the precipitation. The temperature varies from 20 o C - 39 o C and the average temperature is about o c. Average relative humidity of the study area is 63.52% Sampling The study was carried during December 2010 to June A thorough reconnaissance survey was conducted throughout the study area so as to gathered precise information about the vegetation. Standardization of quadrate size was carried out by following Species Area Curve method for trees (Cain, 1938). Stratified random sampling technique was adopted for vegetation sampling. Roughly about 10% sampling was carried out. Twenty five quadrates of 10m x 10m size were taken from the study area Primary Analysis Primary analysis of the vegetation was carried out to obtain the values of various parameters like Density, Relative Density, Frequency, Relative Frequency, Abundance, Relative Abundance, and Importance Value Index (IVI) (Curtis and Mc-Intosh 1950; Misra and Puri 1954; Muller-Dombois and Ellenberg, 1974). 1896

3 3. Results and discussions The results of the vegetation analysis are given in Table 1. Table 1: Phytosociological analysis of Tree species Sl. No Species Family Conservation Status D F 1 Hopea ponga Dipterocarpaceae C Hopea parviflora Dipterocarpaceae C Adenanthera pavonina Caesalpiniaceae C Anogeissus latifolia Combretaceae C Lagerstroemia microcarpa Melastomaceae C Cassia fistula Caesalpiniaceae C Leea indica Vitaceae C Pongamia pinnata Papilionaceae C Carallia brachiata Rhizophoraceae C Tectona grandis Verbanaceae C Terminalia bellirica Combretaceae C Syzigium travancoricum Myrtaceae EC & E Holigarna arnottiana Anacardiaceae C Terminalia paniculata Combretaceae C Mallotus philippensis Euphorbiacea C Mesua ferrea var. ferrea Guttiferae C Mimusops elengi Sapotaceae C Syzygium cumini var. 18 cumini Myrtaceae C Polyatlhia korinti Annonaceae EC & C Macaranga peltata Euphorbiaceae C Evodia roxhurghiana Rutaceae C Xylia xylocalpa Mimosaceae C Acronychia laurifolia Rutacaea C Lannea coromandelica Anancardiaceae C Saraca asoca Caesalpiniaceae C Cinnamomum Zeylanicum Lauraceae EC Dipterocarpus heterophyllus Dipterocarpaceae C Trema orientalis Ulmaceae C Careya arborea Lecythidaceae C Goniothalamus cardiopetalus Annonaceae EC Cinnamomum malabathrum Lauraceae EC

4 32 Albizzia chinensis Mimosaceae C Lophopetalum wightianum Icanaceae C Allophylees cobbe Sapindaceae C Sterculia foetida Sterculiaceae C Syzigium caryophyllata Myrtaceae C Xanthophyllum flavescens Polygalaceae C Caryota urens Palmaceae C Vitex altissima Verbanaceae C Diospyros perrebrina Ebenaceae C Strychnos nux-vomica Loganiaceae C Diospyros buxifolia Ebenaceae C Evodia lunu-ankenda Rutaceae C Holigarna beddomei Anacardiaceae C Persea macrantha Lauraceae C Syzigium zeylanicum Myrtaceae EC Zanthoxylum rhetsa Rutaceae C Alstonia scholaris Apocyanaceae C Artocarpus hirsutus Moraceae EC Bridelia airy - shawi Euphorbaceae C Dillenia pentagyna Dilleniaceae C Hydnocarpus alpine Bixaceae EC Sapium insigne Euphorbiaceae C Sterculia guttata Sterculiaceae EC & C Myristica malabarica Myristicaceae EC & R Plumeria rubra Apocyanaceae C Beilschmiedia wightii Lauraceae C Bridelia scandens Euporbiaceae C Butea monosperma Papilionaceae E Myristica fatna Myrsticaceae EC & C Oroxylum indicum Bignonaceae EC & T Pterocarpus marsupium Papilionaceae C Holoptelea integrifolia Ulmaceae C TOTAL INDEX: C= Common, EC= Endemic, R= Rare, E= Endangered, T= Threatened, D= Density, F= Frequency Table 2: Phytosociological analysis of Tree species (Continuing) Sl. No Species R D R F IVI R IVI 1 Hopea ponga Hopea parviflora Adenanthera pavonina Anogeissus latifolia

5 5 Lagerstroemia microcarpa Cassia fistula Leea indica Pongamia pinnata Carallia brachiata Tectona grandis Terminalia bellirica Syzigium travancoricum Holigarna arnottiana Terminalia paniculata Mallotus philippensis Mesua ferrea var. ferrea Mimusops elengi Syzygium cumini var. cumini Polyatlhia korinti Macaranga peltata Evodia roxhurghiana Xylia xylocalpa Acronychia laurifolia Lannea coromandelica Saraca asoca Cinnamomum Zeylanicum Dipterocarpus heterophyllus Trema orientalis Careya arborea Goniothalamus cardiopetalus Cinnamomum malabathrum Albizzia chinensis Lophopetalum wightianum Allophylees cobbe Sterculia foetida Syzigium caryophyllata Xanthophyllum flavescens Caryota urens Vitex altissima Diospyros perrebrina Strychnos nux-vomica Diospyros buxifolia Evodia lunu-ankenda Holigarna beddomei Persea macrantha

6 46 Syzigium zeylanicum Zanthoxylum rhetsa Alstonia scholaris Artocarpus hirsutus Bridelia airy - shawi Dillenia pentagyna Hydnocarpus alpine Sapium insigne Sterculia guttata Myristica malabarica Plumeria rubra Beilschmiedia wightii Bridelia scandens Butea monosperma Myristica fatna Oroxylum indicum Pterocarpus marsupium Holoptelea integrifolia TOTAL INDEX: RD= Relative Density, RF= Relative Frequency, IVI= Importance Value Index, RIVI= Relative Importance Value Index. Data on Phytosociological analysis of trees of Alakyam stream sorted on the basis of IVI values are represented in the Table 2. A total of about 63 species of trees were recorded from the twenty five sample plots of 10 m X 10 m size taken from the study area. The species with maximum number of individuals are Hopea ponga (60), Hopea parviflora (19), Syzygium travancoricum (14), Adenanthera pavonina (14) etc. Hopea ponga has the highest density (55.1) followed by Hopea parviflora (17.1) Syzygium travancoricum(12.86) Anogeisus latifolia (12.86) etc. Total density of the study area is 406.8/ha. The highest density of Hopea ponga indicates the relationship between stream and plant species through seed dispersal. Out of 63 tree species recorded in Alakyam stream area, 10 species show frequency of more than 50%. Hopea ponga is the most frequent species with a value of 70% followed by Adenanthera pavonina (60%), Lagestromea microcarpa (60%), Anogeiossus latifolia (60%) etc. Even though density of Hopea ponga is high, frequency is relatively low and it may be due to anthropogenic disturbances in the study area. The species with maximum importance values are Hopea ponga (17.22), Hopea parviflora (6.92), Adenanthera pavonina (6.32), Anogeissus latifolia (6.32), Lagerstroemia microcarpa (5.42), etc. Only Hopea ponga has an IVI above 10. Phytosociology of vegetation shows that Hopea ponga is the important species in the study area and that species is under threat. As an endemic and endangered species, the conservation of Hopea ponga is necessary and for that protection of Alakyam stream is essential. The distribution of number of individual species as per their IVI is given in Table Conservation status of species of Alakyam stream area The ecological status (Conservation status) of species of Alakyam stream area is given in table

7 Table 3: RET categories of Tree species of Alakyam stream area Sl. No. Species Status # 1 Artocarpus hirsutus Endemic 2 Butea monosperma Endemic 3 Cinnamomum malabathrum Endemic 4 Cinnamomum zeylanicum Endemic 5 Goniothalamus cardiopetalus Endemic 6 Hopea parviflora Endemic & Endangered 7 Hopea ponga Endemic & Endangered 8 Hydnocarpus alpine Endemic 9 Lannea coromandelica Endemic 10 Leea indica Endemic 11 Myristica fatua Endemic 12 Myristica malabarica Endemic & Rare 13 Oroxylum indicum Endemic & Threatened 14 Polyalthia korinty Endemic 15 Sterculia gutta Endemic 16 Syzygium travancoricum Endemic & Endangered 17 Syzygium zeylanicum Endemic # - [(Source: IUCN RED listed species in South India (IUCN )] In the case of Ecological status (Conservation status), 73% species of encountered trees are common. About 27% (Endemic & Common = 17% + Endemic RET =10) category of the flora (Trees) present in the study area is endemic to Western Ghats. About 10% of the tree species belongs to RET category (Endemic & Endangered = 5%, Endemic & Rare = 2% and Endemic & Threatened = 3%). The percentage distribution of tree species in various Ecological statuses is given in figure 1. Figure 1: Percentage distribution of species in various conservation status 1901

8 Plants like Hopea ponga and Hopea parviflora have the highest ecological importance in the area. These plants are included in IUCN red data book as endangered plant species. The presence of stream had a great influence on the survival of these riparian plants especially in terms of seed dispersion. Another important finding in this study was the presence of a critically endangered tree species, Syzygium travancoricum along the banks of stream especially near the national highway -17. Unfortunately many of the plants with higher conservation priority are at risk and the areas were utilizing for developmental activities like road widening, building construction etc. Stream pollution by solid waste disposal is one of the important threats facing by the Alakyam stream. One of the important drawbacks of conservation measures implemented by the competent authority is that they absolutely ignored the importance of small scale local diversity of plants especially in rural and urban midland and 90% of the land at both the banks of the stream are under private sector. That may lead to the destruction of vegetation in future. Implementation of conservation strategies with a special emphasis on RET plants (Rare, Endemic, Threatened) of the study area is time needed one. Actions should be taken to minimize the solid waste deposition in Alakyam stream. Awareness of local people about the significance of Alakyam Stream and presence of riparian vegetation along the banks of the stream are also necessary to protect such a precious ecosystem. 4. Conclusion This study reveals the status of diversity of riparian tree species. The Phytosociological results indicate the need of adoption of a strong ecosystem management strategy particularly for the rare, endemic flora of this region. In order to protect them, conservation of the Alakyam stream is necessary and measures to be taken by Local Authority to conserve it. 5. References 1. Angermeier P. L., (2000), The Natural imperative for biological conservation, Conservation Biology, 14, pp Cain S. A., (1938), The species area curve, Amer. Mid. Nat, 19, pp Curtis. J. T., and Mc. Intosh R. P., (1950), The interrelations of certain analytic and synthetic phytosociological characters, Ecology, 31, pp Grove R.H., (1995), Green Imperialism. Cambridge University Press, Cambridge U.K, 540 pp Hill J.L., (2001), Why are tropical rain forests species rich? Classifying, reviewing and evaluating theories, Progress in Physical Geography, 25, pp (166). 6. IUCN Red List of Threatened Species, (2007) 7. Ksornhoae S., (1993), Ecology and Management of Mangroves, IUCN Bangkok, pp Laurance W.F., (2002), Ecosystem decay of Amazonian Forest Fragments, Conservation Biology, 16, pp (177, 179 and 180). 9. Misra. R., and Puri G. S., (1954), Indian Manual of Plant Ecology, English Book Depot, Dehradun, pp

9 10. Muller Dombois. D., and Ellenberg H., (1974), Aims and Methods of Plant Ecology, John Wiley and sons. New York, p Niemi. G.J., and Mc Donald M.E., (2004), Application of ecological indicators, Annual Review of Ecology, Evolution and Systematic, 35, pp (57). 12. Palmer M.A., (1997), The application to the British flora of the world conservation union s revised Red List Criteria and the significance of Red Lists for Species conservation. Biological Conservation, 82, pp (40). 13. Suter G.W., (1993), A Critique of Ecosystem Health Concepts and Indices, Environmental toxicology and chemistry, 12, pp (32). 1903