Species composition and distribution of marine algae at Con Co island, Quang Tri province

Nội dung text: Species composition and distribution of marine algae at Con Co island, Quang Tri province

1. Vietnam Journal of Marine Science and Technology; Vol. 21, No. 1; 2021: 67–76 DOI: Species composition and distribution of marine algae at Con Co island, Quang Tri province Dam Duc Tien1,2,*, Nguyen Thi Mai Anh1, Nguyen Manh Linh1,2, Cao Van Luong1, Pham Van Chien1 1Institute of Marine Environment and Resources, VAST, Vietnam 2Graduate University of Science and Technology, VAST, Vietnam *E-mail: tiendd@imer.vast.vn Received: 18 October 2020; Accepted: 24 February 2021 â2021 Vietnam Academy of Science and Technology (VAST) Abstract This paper presents results on species composition and distribution of marine algae at 6 transects of Con Co islands in May 2020. The result of studies shows that 95 species of marine algae are recorded in the study area, belonging to four divisions: Cyanophytes, Rhodophytes, Ochrophytes and Chlorophytes. Among them, five (5) species are classified into Cyanophytes (comprising 5.3% of total species); forty one (41) species into Rhodophytes (43.1%); twenty-nine (29) species into Ochrophytes/Phaeophytes (30.5%) and twenty (20) species into Chlorophytes (21.1%). The species composition of marine algae in Con Co shows significant differences as follows: 48 species (transect number I) to 72 species (transect number IV) and the average value is 60.7 species per transect. Sứrensen similarity coefficient fluctuates from 0.56 (transects number I and II) to 0.81 (transects number II and IV, number III and IV) and the average value is 0.70. The current investigations show that twenty-two (22) species are distributed the littoral zone (22.9% of total species) only and thirty-seven (37) species in the sub-littoral zone only. In which there are thirty six (36) species distributed in both littoral zone and sub-littoral zone (44.8%). The algal flora in Con Co is characterized by subtropics. Keywords: Con Co, composition, distribution, marine algae, species. Citation: Dam Duc Tien, Nguyen Thi Mai Anh, Nguyen Manh Linh, Cao Van Luong, Pham Van Chien, 2021. Species composition and distribution of marine algae at Con Co island, Quang Tri province. Vietnam Journal of Marine Science and Technology, 21(1), 67–76. 67
2. Dam Duc Tien et al. INTRODUCTION sections of Con Co island in the mission: Marine macroalgae are not only a crucial “Supporting scientific research activities for and valuable economic component of marine senior researchers in 2019”, code: resources that people around the world use in NCVCC23.5/19–19. many aspects of life but also a significant In addition, we also refer to the available object in theoretical research. research results, including: In practice, marine macroalga is used as a 1. The results of the project: “Economic raw material for many industries as agar, evaluation of typical sea-island ecosystems alginate, carrageenan, biological compounds serving the sustainable development of some (amino acids, growth hormones, ). These frontage islands in coastal areas of Vietnam” active ingredients have been and will be widely (KC09.08/11–15); used in various fields (textile fabric, additives 2. Investigation of special resources in for beverage industry, specialized glues, coastal areas from Mong Cai to North Hai Van pharmaceutical preparations). In our country pass (1992–1993). today, seaweed has been used in a number of industries (especially extracted glues, Research methods compounds) [1, 2]. Sampling method Con Co is small island, belongs to Quang Vietnam Academy of Science and Tri province and is 13–17 nautical miles from Technology, 2014. “Investigation Process of land to the East. The nearest point is from Mui Marine Resources and Environment - Section Lay in Vinh Thach commune, Vinh Linh Biology and Environmental Chemistry” [4] (for district 13 nautical miles, from Cua Tung 15 tidal zone) and the standard method of English nautical miles, Cua Viet 17 nautical miles [3]. et al., (1997) [5] (for subtidal zone) were used Currently, studies on marine macroalgae in in the survey. The specimens in the subtidal Con Co island are few and this is the first zone were collected by SCUBA divers. We complete result on species composition and used SCUBA diving equipment, underwater distribution seaweed in Con Co island. digital camera OLYMPUS (Tokyo, Japan) for This paper presents species composition collecting samples and taking pictures. and distribution of marine macroalgae in Con The freshly collected marine macroalgal Co, Quang Tri province through the mission: samples were soaked in a solution of “Supporting scientific research activities for formaldehyde 5%, the specimens were then put senior researchers in 2019”, code: on Croki paper, compressed into blotting NCVCC23.5/19–19. papers, dried naturally and identified. The survey was conducted at 6 cross MATERIALS AND METHODS sections (symbols CC1, CC2, CC3, CC4, CC5 Materials and CC6) perpendicular to the island shoreline The paper is based on the results obtained and extended from low tide to the subtidal zone through the May 2020 survey at 6 cross to a depth of 15 m (table 1 and figure 1). Table 1. Coordinates of survey points at Con Co island No. Template notation Coordinates 1 CC1 17o09’22”N - 107o19’07”E 2 CC2 17o09’41”N - 107o19’86”E 3 CC3 17o10’25”N - 107o20’55”E 4 CC4 17o9’28”N - 107o20’96”E 5 CC5 17o09’56”N - 107o20’64”E 6 CC6 17o09’56”N - 107o20’64”E 68
3. Species composition and distribution of marine algae Figure 1. Diagram of seaweed survey on Con Co island Species identification information is searched based on the document The marine macroalgal specimens were of Nguyen Van Tu et al., [16]. analyzed at the laboratory of Marine Botanical The floral characteristic was calculated by Ecology and Resources Department, Institute the Cheney formula (1977). This method of Marine Environment and Resources involves calculating the sum of the number of (Vietnam Academy of Science and species of Rhodophytes, Chlorophytes and Technology). Specimens were classified based dividing this by the number of species of on criteria relating to the morphology and Phaeophytes. If the ratio is 6, it is The classification document is based on the recognized as the tropical flora [17]. authors such as: Taylor (1960) [6]; Segawa S. Distribution study (1962) [7]; Pham Hoang Ho (1969) [8]; Tseng Geographical distribution et al., (1983) [9]; Nguyen Huu Dinh et al., Geographical distribution in this study (1993) [10]. referred to the spatial horizontal distribution of The classification of seaweed follows the marine macroalgae. general principles of plant classification [11]. To study the geographical distribution of The hierarchical order of taxa is arranged marine macroalgal communities, similarity according to the system of Golerbackh (1997) index (Sorensen similarity index) was [12], the sub-sector taxon is based on Frederik calculated according to the formula S = Leliaert et al., [13], Guiry M. D., Guiry G. M. 2C/A+B, where A and B are the numbers of [14]. Names of taxa are used according to the species in sample sites A and B, respectively general standard provisions of the Tokyo and C is the number of species shared by two nomenclature [15]. Some additional sampling sites (A and B) [18]. 69
4. Dam Duc Tien et al. When the coefficient value approaches 1, RESULTS AND DISCUSSION these sampling sites show a strong similarity; Species composition when coefficient value approaches 0, these Based on the analysis of marine macroalgal sample sites are less similar. samples collected during field surveys in May Vertical distribution 2020 at 6 stations and from a review of Determining the vertical distribution of published data, we identified a total of 95 marine macroalgae was based on the principle species of marine algae in the study area, of the partitioning (zonation) of the tidal zone belonging to four divisions: Cyanophytes, as used by Feldmann (1937) [19], Stephenson Rhodophytes, Ochrophytes and Chlorophytes. (1949) [20] and Pham Hoang Ho (1962) [21]. Among them, five (5) species are classified into Under this scheme, the coastal zone is Cyanophytes (comprising 5.3% of total arbitrarily partitioned into many different areas species); forty-one (41) species into depending on the tidal level such as high tide, Rhodophytes (43.1%); twenty-nine (29) species mid-tide and low tide. Water level and tidal into Ochrophytes/Phaeophytes (30.5%) and data were derived from the tidal regime twenty (20) species into Chlorophytes (21.1%) measured at Cua Viet in May 2019 [22]. (table 2). Table 2. Species composition and distribution of marine macroalgae at Con Co island Geographical distribution Vertical distribution No. Taxa I II III IV V VI a b Cyanophyta Oscillatoriaceae 1 Lyngbia aestuarii (Mert.) Liebm. + + + + + + + 2 L. lutea (C. Ag.) Gom + + + 3 L. martensiana Menegh. + + 4 Microcoleus chthonoplaste Thur. et Gom + + + + + + + 5 Symploca hydnoides Kuetz. ex Gom. + + + + + Rhodophyta Bangiaceae 6 Porphyra suborticulata Kjellm. + + + Liagoraceae 7 Liagora divaricatat Tseng + + + + + + 8 L. caenomyce Dcne. + + + + + + 9 L. orientalis J. Ag. + + + + + Galaxauraceae 10 Galaxaura fastigiata Decne + + + + + + 11 G. rugosa (J. Ellis et Solander) J. V. Lamouroux + + + + + + 12 G. obtusata (Ell. et Sol.) Lamx. + + 13 Actinotrichia fragilis (Forsk.) Boerg. + + + Gelidiellaceae 14 Gelidiella acerosa (Forsk.) Feld. & Ham. + + + + + + + 15 G. lubrica (Kuetz.) Feldm. et Ham. + + + + + + Gelidiaceae 16 Gelidium crinale (Turn.) Lamx. + + + + 17 G. lithophila Boerg. + + + + + + + 18 G. pulchellum (Turn.) Kuetz. + + + + + + Peyssonneliaceae 19 Peyssonnelia gunniana J. Ag. + + + + Corallinaceae 20 Coralina officinalis L. + + + + 21 Jania capillacea Harv. + + + + 22 J. pumila Yendo + + + + Lithophyllaceae 70
5. Species composition and distribution of marine algae 23 Amphiroa achigoensis Yendo + + + 24 A. zonata Yendo + + + Halymeniaceae 25 Halymenia dilitata Zan. + + + + Acrochaetiaceae 26 Acrochaetium thuretti (Bornet) F. S. Collins & Hervey + + Hypneaceae 27 Hypnea boergesenii Tanaka + + + + 28 H. esperi Bory + + + + 29 H. flagelliformis Grev. + + + + + 30 H. japonica Tanaka + + + + 31 H. nidulans Secth + + + + Gracilariaceae 32 Gracilaria arcuata Zan. + + + + + + 33 G. salicornia (C. Ag.) Daws. + + + + + Gigartinaceae 34 Gigartina intermedia Sur. + + + + Bonnemaisoniaceae 35 Asparagopsis taxiformis (Del) Coll. et Harv. + + + + + Phyllophoraceae 36 Ahnfeltiopsis griffithsiae (Turn.) Mart. + + + + + + + Rhodomelaceae 37 Polyshiphonia nhatrangense Phamhoang H. + + + + + + + 38 P. sertularioides (Grot.) J. Ag. + + + + + + + + 39 P. subtilissima Mont. + + + + 40 P. sphaerocarpa Boerg. + + + + 41 Laurencia obtusa (Huds.) Lamx. + + + + 42 Acanthophora muscoides (L.) Bory + + + + + + 43 A. spicifera (Vahl.) Boerg. + + + + + 44 Leveillea jungermanioides (Harv. & Mart.) Harv. + + + + + + + 45 Acrocystis nana Zan. + + + + + + + Rhodymeniaceae 46 Ceratodiction spongiosum Zanard. + + + + + + Ochrophyta (Phaeophyta) Ectocarpacea 47 Feldmannia irregularis (Kuetz.) Ham. + + + + + + + + Scytosiphonaceae 48 Colpomenia sinuosa (Roth.) Derb. et Sol. + + + + + + + + Chnoosporaceae 49 Chnoospora minima (Her.) Papenf. + + + + + 50 Ch. implexa (Hering) J. Ag. + + + + + Ralfsiaceae 51 Ralfsia verrucosa (Aresch.) J. Ag. + + + + + Sphacelariaceae 52 Sphacelaria variabilis Sauv. + + 53 S. rigidula Kỹtzing + + + + + + Dictyotaceae 54 Dictyota adnata Zanardini + + + + + + 55 D. divaricata Lamx. + + + + + + 56 D. ceylanica var. anastromosans Ta. + + + + + + 57 D. patens J. Ag. + + + + + 58 Padina australis Hauck. + + + + + + + + 59 P. boryana Thivy + + + + + 60 P. crassa Yam. + + + + 61 P. tetrastroma Hauck. + + + + + + + 62 Lobophora variegata (Lamx.) Wom. + + + + + + + + 71
6. Dam Duc Tien et al. Scytosiphonaceae 63 Hydroclathrus clathratus (Bory) Howe. + + + + + Chordariaceae 64 Nemacystus decipiens (Sun.) Kack. + + + + Sargassaceae 65 Sargassum aquifolium (Turner) C. Agardh + + 66 S. duplicatum J. Ag. + + 67 S. echinocarpum I. Ag. + + + + + 68 S. glaucescens J. Ag. + + + + + + 69 S. gracillimum Rbd. + + + + 70 S. kuetzingii Setch. + + + + + 71 S. paniculatum J. Ag. + + + + + + 72 S. polycystum C. Ag. + + + + + 73 S. polyporum Mont. + + + + + + 74 Sargassum siliquosum J. Ag. + + + + 75 Turbinaria gracilis Sond. + + + + + + + Chlorophyta Ulvaceae 76 Ulva clathrata (Roth.) Grev. + + + + + + + 77 Ulva flexuosa (Wult.) J. + + + + + + + Anadyomenaceae 78 Anadymene wrightii Harv. + + + + Boodleaceae 79 Boodlea siamensis Reinb + + + + + + + Cladophoraceae 80 Chaetomorphaantennina (Boerg.) Kuetz. + + 81 Chaetomorpha crassa (C. Ag.) Kuetz. + + + 82 Rhizoclonium riparium (Roth.) Harv. + + + + + Bryopsidaceae 83 Bryopsis pennata Lamx. + + + + + + + Caulerpaceae 84 Caulerpa. lentiliffera J. Ag. + + + + 85 Caulerpa peltata Lamx. var. Typica W. V. Bosse + + + + + + + 86 Caulerpa serrulata (Forsk.) J. Ag. + + + + + + + 87 Caulerpa racemosa (Forsk.) J. Ag. + + + + + + + 88 Caulerpa. taxifolia (Vahl.) C. Ag. + + + + + Codiaceae 89 Codium arabicum Kuetz. + + + + + + + 90 Codium tenue Kuetz. + + + + + + Halimedaceae 91 Halimeda macroloba Decn. + + + + + + + Udoteaceae 92 Chlorodesmis hildebrandtii A. et E. S. Gepp + + + Dasiacladaceae 93 Neomeris annunata Dich. + + + + + + + 94 Neomeris Vanbosseae Howe + + + + + Polyphysaceae 95 Acetabularia parvula Solms-Laubach + + + + + + + + Total: 95 species 48 60 71 72 58 55 58 73 Notes: I, II, III, IV, V and VI are sampling sites; “a” as intertidal zone, “b” as subtidal zone. The algal flora index C = (41 + 20)/29 = 2.10. This value is Based on Cheney’s method and results between 0 and 3. Thus, the algal flora in Co To obtained from table 2, we determine that the and Thanh Lan is characterized by subtropics. 72
7. Species composition and distribution of marine algae Distribution difficult for seaweed to survive and develop, Geographical distribution which is the reason for the difference in the Table 2 shows that the number of species at number of species between the sections. different sites ranges from 48 species (site I) to The Sorensen index of marine macroalgae 72 species (site IV) with the average value of at different sites ranged from 0.56 (between 60.7 species/site. sites I and II) to 0.81 (between sites I I and IV) and the average value was 0.70 (table 3). Table 3. Sorensen index values between sites Although the distance between sections I at Con Co island and II is not far and the base is mainly coral reefs, the similarity coefficient is the lowest I II III IV V VI (0.56), because the construction of the wharf VI 0.57 0.68 0.74 0.74 0.68 (section I) has changed the basal structure and V 0.60 0.73 0.73 0.76 impacted on seaweed survival. The average IV 0.66 0.81 0.81 value between sites II and IV reached the III 0.61 0.77 highest (0.81) because the bottom structure and II 0.56 other conditions (salinity, light intensity, I flow, ) were relatively similar. Notes: I, II, III, IV, V and VI are sampling sites. The mean value for the six cross sections The average number of species reaching reaching 0.70 is relatively high. The reason is 60.7 species/site is relatively high. This result that the survey sites are relatively close is completely consistent because Con Co is an together because Con Co is an island with a offshore island, less affected by fresh water small area, the natural conditions are quite from the continent, the amount of alluvium similar, so there is no big difference in species and sediment almost does not affect the clarity composition (table 3). of seawater, so the transparency is usually Vertical distribution high with stable salinity. These are very Based on tidal level data in May 2020 at favorable conditions for the survival and Cua Viet, among 95 species in Con Co island, development of marine macroalgae, making there were 22 species (occupying 23.1% of the average number of species at the cross total species) distributed in intertidal zone only section relatively high. However, at a few and 37 species (38.9%) in subtidal zone only points on the sections (the bottom structure is (in which 36 species (38.0%) were distributed dead coral interbedded with light sand), it is in both intertidal and subtidal zones). Table 4. The distribution of marine macroalgae by depth in Con Co island (Based on tide level in Cua Viet, May 2020) Region Tidal belt Featured species There is no seaweed On the tide The average value of the tropical spring tide 0.8 m Chaetomorpha antennina, Ulva clathrata, Ulva flexuosa, High tide belt The average value of the equator spring tide 0.7 m Porphyra suborticulata, Gelidium crinale, Gelidiella acerosa, Tidal area Middle tide belt The average value of the equator neap tide 0.3 m Gelidiella lubrica, Colpomenia sinuosa, Feldmannia irregularis, Low tide belt The average value of the tropical neap tide 0 m Hypnea boergesenii, Chnoospora implexa, Bryopsis pennata, High belt Subtidal area -10 m Low belt Galaxaura fastigiata, Peyssonnelia calcea, Jania capillacea, The results in table 4 show that in the following species: Chaetomorpha antennina, intertidal area, the high tide belt usually has the Ulva clathrata, Ulva flexuosa, ; middle tide 73
8. Dam Duc Tien et al. belt: Porphyra suborticulata, Gelidium crinale, group was not collected (genera Porphyra, Gelidiella acerosa, ; low tide belt: Gelidiella Bangia, Grateloupia, ). If the surveys are lubrica, Colpomenia sinuosa, Feldmannia carried out in winter, the number of species irregularis, ; in the subtidal tide area, the high here may be even higher. belt usually has the following species: Hypnea The survey trip in May 2020 was also not boergesenii, Chnoospora implexa, Bryopsis favorable due to the weather conditions and pennata, and low belt: Galaxaura fastigiata, leap year, so the seaweed crop was also Peyssonnelia calcea, Jania capillacea, changed. An additional survey is expected in Conclusion the months to come, but due to disease and Con Co island is located in the mouth of weather, it cannot be implemented. This also the Tonkin Gulf. This is the midpoint between affects the number of seaweed species that can the sub-tropical zone (in the North) and the be recorded at Con Co. mixed zone (in the South). Survey results in Compared to other islands in the Tonkin May 2020 found 95 species of marine Gulf, the number of species detected in Con Co macroalgae. This number is much higher than island is the highest (95 species), those in other the survey results in 2014 by Dam Duc Tien islands are lower: Bach Long Vi (46 species), (71 species) [20] and in 2013 by Do Anh Duy Ba Mun (11), Vinh Thuc island (68), Ha Mai and Do Van Khuong (52 species) [22]. Thus, island (19). The highest number of species on in this study, 25 species have been added to Con Co island is in compliance with the law the list of Con Co seaweed. since Con Co island has a base of mostly dead Since most surveys on Con Co island were rocks or corals. In addition, the number of only conducted in the summer (usually high species also follows the distribution of aquatic temperatures), a complete winter species organisms (table 5). Table 5. The number of the marine algae species in Con Co in 2020 compared with previous studies in the Tonkin Gulf area Study area Species number Reference Bach Long Vi island 46 Dam Duc Tien (1997) [23] Tran island 34 Dam Duc Tien (2004) [24] Ha Mai island 19 Dam Duc Tien (2004) [24] Co To island 53 Do Anh Duy, Do Van Khuong (2013) [26] Ba Mun island 11 Do Anh Duy, Do Van Khuong (2013) [26] Vinh Thuc island 68 Do Anh Duy et al., (2019) [25] Co To and Thanh Lan island 76 Dam Duc Tien et al., (2020) [28] Con Co island 52 Do Anh Duy, Do Van Khuong (2013) [26] Con Co island 71 Dam Duc Tien (2014) [27] Con Co island 95 This study At present, because the renovation and Natural conditions such as clear water, little construction of coastal structures happen influence of fresh water from the continent, frequently and in a long time, at many points it hard bottom, narrow tidal area, low tidal will certainly affect the wide distribution of fluctuations are very favorable for seaweed to seaweed. The number of species at different survive. In the summer period, the water cross sections can have more variation. temperature is usually high, the water drains Due to the fact that most of the surveyed mainly during the day, so it is not favorable for sections at Con Co island have a hard bottom the existence and development of seaweed in structure, great slope, narrow tidal area and low the tidal area. However, some other conditions tidal range, the daytime exposure does not have are very favorable for the distribution in the a large effect on the distribution of seaweed. subtidal area, so the season of seaweed tends to 74
9. Species composition and distribution of marine algae be longer, and they are distributed deeper in the - Section Biology and Environmental subtidal area. Chemistry. Publishing House for Science and Technology, Hanoi, 216 p. CONCLUSION (in Vietnamese). At Con Co island, we have identified 95 [5] English, S., Wilkinson, C., and Baker, V., species of marine macroalgae. They belong to 4 1997. Survey manual for tropical marine phyla of marine macroalgae consisting of 5 resources. 2nd Edn., Australian Institute of species of Cyanobacteria, representing 5.3% of Marine Science, Townsville, Australia, the total number of species, 41 species of 390 p. Rhodophytes (43.1%), 29 species of [6] Taylor, W. R., 1960. Marine algae of the Phaeophytes (30.5%) and 20 species of eastern tropical and subtropical coasts of Chlorophytes (21.1%). The algal flora in Con the Americas. Univ. Mich. Press. Ann. Co is characterized by subtropics. Arbor., 1963, 111. The geographical distribution of marine [7] Segawa, S., 1957. Coloured illustrations macroalgae at Con Co is not similar; they of the seaweeds of Japan (Vol. 18). ranged from 48 species (site number I) to 72 Hoikusha. species (site number IV) and the average value [8] Pham Hoang Ho, 1969. Vietnam seaweed is 60.7 species/site. Sorensen index of marine (Southern part). Learning Resource macroalgae at six (6) sites ranged from 0.56 Center, Saigon. 558 p. (between sites I and II) to 0.81 (between sites II [9] Tseng, C. K., (ed.), 1984. Common and IV) and the average value was 0.70. seaweeds of China. Beijing, Science Among 95 species of marine macroalgae Press; Amsterdam and Berkely, Kugler at Con Co island, there are 22 species Publications. 326 p. (occupying 22.9% of total species) [10] Nguyen Huu Dinh, Huynh Quang Nang, distributed in intertidal area only and 37 Tran Ngoc But and Nguyen Van Tien, species (32.3%) in subtidal area (in which 36 1993. Marine macroalgae (In the North species - 44.8% were distributed in both Vietnam). Science and Technics Publishing intertidal and subtidal areas). House, Hanoi. 364 p. (in Vietnamese). Acknowledgements: We would like to thank [11] Nguyen Tien Ban, 1997. Principles of the mission: “Support scientific research taxonomy and botanical system. In: A activities for senior researchers in 2020”, code: series of graduate lectures at the National NCVCC23.5/20–20 for supporting this study. Center for Natural Sciences and Technology. 56 p. (in Vietnamese). REFERENCES [12] Gollerbakh, M. M., 1977. Life of Plants in [1] Chapman, V. J., and Chapman, D. J., Six Volumes. Vol. 3: Algae. Lichens. 1980. Seaweeds and their uses (No. Prosveshchenie, Moscow, 488 p. 632.58 C43 1980). [13] Leliaert, F., Smith, D. R., Moreau, H., [2] Titlyanov, E. A., and Titlyanova, T. V., Herron, M. D., Verbruggen, H., Delwiche, 2012. Marine plants of the Asian Pacific C. F., and De Clerck, O., 2012. Phylogeny region countries, their use and cultivation. and molecular evolution of the green Dalnauka and AV Zhirmunsky Institute of algae. Critical Reviews in Plant Sciences, Marine Biology, Far East Branch of the 31(1), 1–46. Russian Academy of Sciences, 07352689.2011.615705. Vladivostok. [14] Guiry, M. D., Guiry G. M., 2015. [3] Quảng Trị, 2021. Algaebase. Worldwide electronic tri.gov.vn/vi/gioi-thieu/gioi-thieu-chung/, publication. National University of accessed on 2021-02-28, 21:13. Ireland, Galway, [4] IMER, 2014. Marine Environmental and Accessed on Natural Resources Investigation Process 2015-08-15. 75
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