International Research Journal of Environment Sciences________________________________ ISSN 2319–1414Vol. 2(5), 79-86, May (2013) Int. Res. J. Environment Sci. International Science Congress Association 79 Invasive Alien Plant Species Assessment in Urban Ecosystem: A Case Study from Andhra University, Visakhapatnam, India Bam Surendra, Ahmedin Annissa Muhammed, Siraj Keredin Temam and Raju A.J. SolomonDepartment of Environmental Science, Amrit Campus, Tribhuvan University, NEPAL Wood Processing and Engineering, Adama Science and Technology University, Adama, ETHIOPIA Department of Environmental Sciences, Andhra University, Visakhapatnam, INDIAAvailable online at: www.isca.in Received 17th April 2013, revised 21st April 2013, accepted 14th May 2013 AbstractThis paper highlights the current status of invasive alien plant species in Andhra University Campus of Visakhapatnam district, India, with background information on habit, nativity, longevity, uses and mode of introduction. Data were collected through Phytosociological method. Altogether 21 species belonging to 15 families were documented. The highest Importance Value Index (IVI) was found for Antigonon leptopus. The data show that Wrightia tinctoria is the most frequently encroached tree species by A. leptopus. Species diversity of Invasive alien plants showed that this study area was highly disturbed. Fabaceae is the most dominant family with 3 species (14%) of contribution. About 62% of these alien species were introduced from Tropical America followed by Tropical South America (9%) and Tropical Africa (4%). Analysis of habit shows that herbs dominate (11 species) followed by shrubs (8) and climbers (2). A search in the literature indicated that several of these species have potential uses for different purposes. Similarly, only 5 Species (24%) seem to have been introduced deliberately and the rest of them unintentional through trade exchanges including grain import. However, quantitative impact of these species on the indigenous flora and invaded ecosystems is yet to be studied. There is an urgent need to develop regional data on Invasive Alien Species (IAS) diversity. Keywords: Andhra university campus, importance value index (IVI), invasive alien species (IAS), Visakhapatnam. Introduction According to the Global Invasive Species Program (GISP), “Invasive alien species (IAS) are non-native organisms that cause, or have the potential to cause, harm to the environment, economies, or human health. Invasive alien species (IAS) are one of the most significant drivers of environmental change worldwide”. Convention for Biological Diversity visualize “biological invasion of alien species as the second worst threat after habitat destruction” and article 8(h) of the Biodiversity Convention asks for measures “to prevent the introduction, control or even eradication of those alien species which threaten ecosystems, habitats or species”. Introduction of these species may occur accidently or through their being imported for a limited purpose and subsequently escaping or deliberately on a large scale. Invasive weeds have faster rates of growth and biomass production compared to native species, high competitive ability, high reproductive efficiency including production of a large number of seeds, efficient dispersal, vegetative reproduction, rapid establishment and other traits that help them adapt to new habitats2,3. Invasive exotic plants are implicated in the decline of threatened and endangered species, because they alter ecosystem processes, change vegetation structures and displace native species, often because they reach high densities and biomass. Establishment of a database of naturalized species is the first step in the development of invasion biology, and will also serve as a stepping-stone for further detailed studies on the biology and impact of individual species. Therefore, investigation of the spread of alien or exotic species has become an imperative issue in the Indian subcontinent and globally. Material and Methods Study Area: Visakhapatnam is a growing city in Andhra Pradesh on the East Coast of India and lies in the northern part of the coast of Coromandel. The Andhra University area under investigation lies between East longitude 83° 15’ - 83° 22’ and North latitude 17° 14’ - 17° 46’and spreads in a sprawling campus of 422 acres. The natural vegetation consists predominantly of dry deciduous and deciduous scrub vegetation. The average temperature is high and uniform and mean annual temperature is approximately 25°C. About 70% of the annual rain is received during South-West monsoon season, average varying from 500-1000mm. Quartzites, quartz veins and red loamy soil are also found in various places of Andhra University. It is of red type and most of it is of least fertile variety.Data Collection Methods: The study was carried out from December 2012 to April 2013. Data were collected through Phytosociological method. The sampling technique was random sampling. Randomly total of 30 plots were taken, 15 from each North and South campus of Andhra University. In each plot a quadrate of 20*20m was randomly selected. Within this International Research Journal of Environment Sciences______________________________________________ ISSN 2319–1414 Vol. 2(5), 79-86, May (2013) Int. Res. J. Environment Sci. International Science Congress Association 80 quadrate, 5*5m quadrates were allocated randomly in two corners for the assessment of shrubs. Likewise herbs regeneration was recorded from nested sampling of 1*1m quadrate within the 5*5m quadrate representing 0.01% intensity. Figure 1, shows the distribution of nested sampling within main quadrate. The detail procedures for making plots have been described by Chhetri (1996). Figure-1 Layout of Quadrates As part of this study, we focused on building a comprehensive list of alien species. All plant species within each quadrate were identified then counted and estimated their cover percentage. In case of perennial herbaceous climber like Antigonum leptopus, nesting sample of 1*1m quadrate were used. In this, A. leptopus shoot were considered as a ramet and was counted as an individual. The collected specimens were identified with the aid of standard literature; Invasive Alien Flora of India and Flora of Visakhapatnam and visual inspection by taxonomists. Family classification follows APG III. The native ranges of the species were recorded from internet resources (e.g., http://www.hear.org/pier/ and http://www.invasivespeciesinfo .gov/plants/main.html) and published literature10-14. Plants were categorized by habit (herb, shrub, climber), by longevity (annual, biennial, perennial), and literature were reviewed for their potential uses. Data Analysis: The quantitative characteristic as Importance Value Index (IVI) and the species diversity indices; Margalef’s index of richness (SR), Shannon-Weiner’s diversity index (H’) and Simpson’s index (D) were calculated according to Zobel et al. (1987)15. Results and Discussion Phytosociological study of the Invasive Alien flora of Andhra University Campus reveals altogether of 21 species belonging to 15 families. According to Reddy, 2008, there are altogether 173 invasive alien plants which are permanently naturalized in India. Quantitative structure of Invasive alien plant species: The study shows a massive number of IAS in Andhra University and Antigonon leptopus is the most threatening one with the highest Importance Value Index (table-1). This result is verified with some other studies, In Hawaii, A. leptopus is commonly cultivated and now sparingly naturalized in disturbed areas16making it more dominant. It is the vine nature of Antigonon leptopus that causes it to have highest coverage and affect the resource apportionment of other species present. The abundance of seedling and the high levels of recruitment observed in the study area also suggest that it will continue to be dominant in the areas where it is established . Diversity of Dominance: The dominance diversity curve has been used to interpret the dominance of species in the community in relation to resource apportionment and niche space17. Figure 2; shows the dominant species as Antigonon leptopus with the IVI 73.257. The dominance diversity curve is very essential to demonstrate resource apportionment and niche space among species over the span of time. Encroachment of Antigonon on Tree species: Regarding, the invasion ability of A. leptopus on tree species, Wrightia tinctoria is the tree most severely encroached by Antigonon leptopus with 18% of this tree being invaded over the study area. This is very important to document because knowing this will help us preserve that particular tree species along with other animal species dependent on it directly or indirectly. For instance, Trewia nudifora, commonly known as Rhino apple tree is being greatly invaded by Mikania micrantha in protected area of Nepal18. The Indian Rhino (Rhinoceros unicornis) which feed on these Trewia nudifora fruit is being greatly affected by such invasion. Therefore, this kind of assessment is more important for ecologically diverse area (figure-3).Diversity Index: The values of Shannon-Wiener index, Simpson's Diversity Index and Species Richness of Invasive alien plant species in Andhra University were 2.306, 0.864 and 3 respectively. These as a whole were showing high evenness of individual type with greater richness and less abundance of particular species.This suggests us that this particular urban ecosystem was highly disturbed providing suitable habitat for variety of alien species and reducing diversity of native one. Exotic invasion is often associated with declines in local plant diversity19. To verify this quantitively in Andhra University Campus, further study on correlation between native species richness and abundance of alien flora should be carried out.Enumerations of alien species are shown along with habit, nativity, longevity, potential uses and mode of introduction (table-2). Taxonomic distribution of Alien flora:In the alien flora of the Andhra University Campus, Fabaceae is the most dominant family with 3 species. Similar results were reported from invasive alien flora of Gadag district, Karnataka, where Fabaceae was also found to dominate and it was stated that the dominance of Fabaceae may be due to the nitrogen-fixing bacteria often associated with these taxa, allowing these species to improve the soil fertility20 (figure-4). 1m 1m 5m 5m 20m 20 m 20 m International Research Journal of Environment Sciences______________________________________________ ISSN 2319–1414 Vol. 2(5), 79-86, May (2013) Int. Res. J. Environment Sci. International Science Congress Association 81 Table-1 Quantitative structure of Invasive alien plant species in Andhra University S.N. Name of Species Common name RD RF RC IVI* 1 Antigonon leptopus Mexican creeper 38.688 13.38 21.189 73.257 2 Sida acuta Wire weed 22.311 11.972 15.587 49.87 3 Cassia occidentalis Coffee senna 1.633 16.901 17.34 35.874 4 Chromolaena odorata Siam weed 0.76 11.972 12.713 25.445 5 Mimosa pudica Sensitive plant 8.426 6.338 4.335 19.099 6 Calotropis gigantea Giant milkweed 0.337 11.268 6.503 18.108 7 Cleome viscosa Dog mustard 9.3375 2.113 4.627 16.0775 8 Dinebra retroflexa Viper grass 8.07 2.817 2.07 12.957 9 Lantana camara Lantana 0.195 4.225 5.114 9.534 10 Hyptis suaveolens Wild spikenard 0.399 4.93 3.166 8.495 11 Parthenium hysterophorus Whitetop weed 2.611 2.817 1.607 7.035 12 Croton bonplandianum Ban tulsi 1.661 2.817 1.34 5.818 13 Datura metel Datura 0.033 2.817 0.633 3.483 14 Alternanthera tenella Joyweed 1.78 0.704 0.731 3.215 15 Argemone mexicana Mexican prickly poppy 1.424 0.704 0.731 2.859 16 Passiflora foetida Stinking passion flower 0.593 0.704 0.609 1.906 17 Cassia alata Ringworm cassia 0.043 0.704 0.974 1.721 18 Cuscuta reflexa Sky creeper 0.593 0.704 0.244 1.541 19 Chloris barbata Swollen finger grass 0.593 0.704 0.122 1.419 20 Gomphrena serrata Prostrate Globe Amaranth 0.356 0.704 0.244 1.304 21 Solanum viarum Tropical Soda Apple 0.119 0.704 0.122 0.945 RF- Relative Frequency, RD- Relative Density, RC- Relative Coverage, IVI- Importance Value Index, *Values are presented in the decreasing order of Importance Value Index (IVI) a- Antigonon leptopus, b- Sida acuta, c- Cassia occidentalis, d- Chromolaena odorata, e- Mimosa pudica, f- Calotropis gigantea, g- Cleome viscosa, h- Dinebra retroflexa, i- Lantana camara, j- Hyptis suaveolens, k- Parthenium hysterophorus, l- Croton bonplandianum, m- Datura metel, n- Alternanthera tenella, o- Argemone mexicana, p- Passiflora foetida, q- Cassia alata, r- Cuscuta reflexa, s- Chloris barbata, t- Gomphrena serrata and u- Solanum viarum. Figure-2 Diversity of Dominance for alien plant species  \n \r \n \r\n \n  \n   \n International Research Journal of Environment Sciences______________________________________________ ISSN 2319–1414 Vol. 2(5), 79-86, May (2013) Int. Res. J. Environment Sci. International Science Congress Association 82 *Trees totally covered were only considered. Figure-3 Encroachment of Antigonon on Tree species of the Andhra University Table-2 List of Invasive Alien Plant Species of Andhra University, Their Source Region and Potential Uses Family Species Longevity Nativity Habit Potential uses Mode of Introduction Amaranthaceae Alternanthera tenella P TA H V UI Gomphrena serrata A TA H M UI Apocynaceae Calotropis gigantea P AF S M UI Asteraceae Chromolaena odorata P TA S BF O Parthenium hysterophorus A TNA H M CA Cleomaceae Cleome 82viscosa A TA H M UI Cuscutaceae Cuscuta reflexa A M H NK UI Euphorbiaceae Croton bonplandianum A TS H CH UI Fabaceae Cassia alata P WI S O O Cassia occidentalis A TSA S M CA Mimosa pudica P TA H O AP Lamiaceae Hyptis suaveolens A TA S FO UI Malvaceae Sida acuta A TA H M UI Papaveraceae Argemone mexicana A TCSA H M UI Passifloraceae Passiflora foetida A TSA C EF UI Poaceae Chloris barbata A TA H FO UI Dinebra retroflexa A TA H FO UI Polygonaceae Antigonon leptopus P TA C O O Solanaceae Datura metel P TA S M UI Solanum viarum P TA S M CA Verbenaceae Lantana camara P TA S W O Longevity – A = Annual; B = Biennial; P = Perennial; Nativity - TA = Tropical America; TSA = Tropical South America; AF = Tropical Africa; WI = West Indies; M = Mediterranean; TS = Temperate South America; TNA = Tropical North America and TCSA = Tropical Central and South America. Habit - H = Herb; C = Climber; S = Shrub; Potential Uses – M = Medical; O = Ornamental; FO = Fodder; CH = Bioactive Chemical; EF = Edible Fruit; V = Vegetable; W = Wood; BF = Bio-fuel and NK = Unknown. Mode of Introduction – O = Ornamental; UI = Unintentional; CA = Contamination of Agri. Import and AP = Agri. Purpose.   International Research Journal of Environment Vol. 2(5), 79-86, May (2013) International Science Congress Association Contribution of Different Geographical Regions: Contribution of different geographical regions in terms of nativity is shown in f igure 5. The contrib America is (62%) noteworthy. The Tropical America contributed 74% of the noxious invasive plants in India American continent contributed majority of the noxious invasive plants in Uttar Pradesh10 and also in China Habit-wise Distribution: The herbs constitute 52% (11 species), shrubs 38% (8 species) and climber 10% (2 species). The habit- wise distribution of alien invasive shown was preponderance of herbs. Habit- wise analysis shows herbaceous species share 151 speci es of Invasive alien species in India The herbs having greater vegetative and tolerance to harsh Taxonomic distribution of Alien flora of Andhra University Contribution of Different Geographical Regions to the Invasive Flora of Andhra University         Environment Sciences_______________ _________________________ International Science Congress Association Contribution of Different Geographical Regions: Contribution of different geographical regions in terms of igure 5. The contrib ution of tropical America is (62%) noteworthy. The Tropical America contributed 74% of the noxious invasive plants in India 14. The American continent contributed majority of the noxious invasive plants in Uttar Pradesh10 and also in China 21. The herbs constitute 52% (11 species), shrubs 38% (8 species) and climber 10% (2 species). wise distribution of alien invasive shown was wise analysis shows herbaceous es of Invasive alien species in India 14. The herbs having greater vegetative and tolerance to harsh conditions could results in the preponderance of herbs allies flora. Potential Uses of Alien flora: indicated that seve ral of these species have potential uses for different purposes. This can be important for management of these alien floras in sustainable way. Further, local consultation with respect to traditional uses of these alien floras can add important information on this aspect Possible mode of Introduction of Alien flora: literature, Only 5 Species (24%) seems to have been introduced deliberately and the rest of them unintentionally through trade exchanges including grain import. Many of known invasive elsewhere also. About 80% of species are included in the Global Compendium of Weeds Figure-4 Taxonomic distribution of Alien flora of Andhra University Figure-5 Different Geographical Regions to the Invasive Flora of Andhra University  !"#$ \n !"#%#$ \n !"#$ \n &#'\r (\r\n\n !\n#%#$ \n !"#)#$ \n !"#*\n#\n\r##$ \n _________________________ ______ ISSN 2319–1414 Int. Res. J. Environment Sci. 83 conditions could results in the preponderance of herbs in the A search in the literature ral of these species have potential uses for different purposes. This can be important for management of these alien floras in sustainable way. Further, local consultation with respect to traditional uses of these alien floras can add on this aspect (figure-6). Possible mode of Introduction of Alien flora: Based on literature, Only 5 Species (24%) seems to have been introduced deliberately and the rest of them unintentionally through trade exchanges including grain import. Many of these species are known invasive elsewhere also. About 80% of species are included in the Global Compendium of Weeds 21 (figure-7). Different Geographical Regions to the Invasive Flora of Andhra University !"#%#$ \n !\n#%#$ \n !"#)#$ \n !"#*\n#\n\r##$ \n International Research Journal of Environment Vol. 2(5), 79-86, May (2013) International Science Congress Association Potential Uses of Alien flora of Andhra University Possible mode of Introduction of Alien flora of Andhra University Campus Based on field ob servation along with literature review indicated that the most noxious invasive plant species in the Andhra University Campus are Antigonon leptopus camara, Chromolaena odorata, Hyptis suaveolens, occidentalis, Calotropis gigantea and hysterophorus which are considered very harmful because of their prolific seed production and ability to spread fast have allelopathic effect on other plants thus giving a strong competition to native flora and crops and are also a healt hazard to humans and domestic animals. Antigonon leptopus damages or kills other plants by cutting out the light and smothering them. In this respect it is especially damaging in young plantations and nurseries. It also competes for water and nutrients.          Environment Sciences_______________ _________________________ International Science Congress Association Figure-6 Potential Uses of Alien flora of Andhra University Figure-7 Possible mode of Introduction of Alien flora of Andhra University Campus servation along with literature review indicated that the most noxious invasive plant species in the Antigonon leptopus , Lantana Chromolaena odorata, Hyptis suaveolens, Cassia and Parthenium which are considered very harmful because of their prolific seed production and ability to spread fast 22. They have allelopathic effect on other plants thus giving a strong competition to native flora and crops and are also a healt h Antigonon leptopus damages or kills other plants by cutting out the light and smothering them. In this respect it is especially damaging in young plantations and nurseries. It also competes for water and However, quantitative impact of these species on the indigenous flora and invaded ecosystems is yet to be studies. Studies are also needed to understand their introduction pathway and status as to whether they have been just recently introduced or are now firmly established and also to quantify the severity of invasion in different habitats. There are four main strategies to control or eradicate invasive species; manual, mechanical, chemical and biological the success of biological control because complete control is only achieved in some years and or at same localities24 . Evidently, there is a need for concerted research on suitable and environmental measures. CAB International on behalf of Global    (\r \n +\n\n ,\r\r - . /\r # 0\n  &\r - . 12   1\n +\n\n *\n\n##$"#' $"#3 _________________________ ______ ISSN 2319–1414 Int. Res. J. Environment Sci. 84 Possible mode of Introduction of Alien flora of Andhra University Campus However, quantitative impact of these species on the indigenous flora and invaded ecosystems is yet to be studies. Studies are also needed to understand their introduction pathway and status as to whether they have been just recently introduced or are now firmly established and also to quantify the severity of invasion There are four main strategies to control or eradicate invasive species; manual, mechanical, chemical and biological 23. Often, the success of biological control programs is not clear-cut because complete control is only achieved in some years and or . Evidently, there is a need for concerted research on suitable and environmental - friendly control measures. CAB International on behalf of Global Invasive (\r \n +\n\n ,\r\r . \n 4#  \n /\r # 0\n  &\r .  12 1\n *\n\n##$"#' International Research Journal of Environment Sciences______________________________________________ ISSN 2319–1414 Vol. 2(5), 79-86, May (2013) Int. Res. J. Environment Sci. International Science Congress Association 85 Species Program (GISP) proposes three major management options – prevention, early detection and eradiction25,26. Conclusion Many alien species are introduced deliberately for intended purposes. Nevertheless, a lot of risk is associated with the introduction of new species. Introduction of Lantana camara, Chromolaena odorata, Antigonon leptopus etc have now become problematic due to their invasion on natural areas and urban ecosystem such as Andhra University Campus. Even biological control should be undertaken only after critical evaluation of the risks involved. Majority of IAS in India are of neo-tropical origin (South America). This is similar to Andhra University Campus having 62% contribution as majority and has been introduced in India by numerous pathways. The knowledge base on IAS control options is limited. This has resulted into numerous problems experienced only after alien species invasion, which do not seem to have easy solution. Therefore, there is a need of better planning for early detection and reporting of infestation of spread of new and naturalised weeds by creation of plant detection network in each State by establishing communication links between taxonomists, ecologists and land managers to monitor and control invasive alien species. Acknowledgements The first author thanks the Ministry of External Affairs (MEA), Government of India, for providing the scholarship to pursue M.Sc. 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