Community Structure and Spatial Distribution of Molluscs in the Mangrove Ecosystem of Rap-Rap Village, South Minahasa
DOI:
https://doi.org/10.35800/jip.v14i2.68703Keywords:
Bray–Curtis, community structure, mangrove, PERMANOVA, Rap-Rap, molluscsAbstract
Mangrove molluscs contribute to detrital processing, trophic transfer, and benthic ecosystem functioning. This study assessed molluscan abundance, diversity, evenness, and community composition at two sampling stations in the mangrove ecosystem of Rap-Rap Village, South Minahasa, North Sulawesi. The cleaned dataset comprised 60 quadrats nested within six transects (three transects per station). Total abundance, relative abundance, frequency of occurrence, species richness, Shannon diversity, Simpson diversity, and Pielou evenness were calculated. Community resemblance was quantified using Jaccard, Sørensen, and Bray–Curtis indices. Differences in community composition were evaluated using transect-level PERMANOVA and multivariate dispersion tests, while non-metric multidimensional scaling and species accumulation curves were used for visualization. A total of 1,304 individuals and 22 molluscan taxa were recorded. Station I contained 743 individuals and 20 taxa, whereas Station II contained 561 individuals and 22 taxa. Shannon diversity was 2.661 and 2.763, and Pielou evenness was 0.888 and 0.894 at Stations I and II, respectively. Littoraria scabra was the most abundant species at both stations. Bray–Curtis similarity was 0.816, indicating a broadly similar abundance structure. PERMANOVA explained 37.4% of the variation in composition (F = 2.395, p = 0.100), but the difference was not significant because only three independent transects were available per station. The communities were diverse and evenly distributed, with higher abundance at Station I and slightly higher richness and diversity at Station II.
Keywords: Bray–Curtis; community structure; mangrove; molluscs; PERMANOVA; Rap-Rap
Abstrak. Moluska mangrove berperan dalam pengolahan detritus, transfer trofik, dan fungsi ekosistem bentik. Penelitian ini menganalisis kelimpahan, keanekaragaman, kemerataan, dan komposisi komunitas moluska pada dua stasiun di ekosistem mangrove Desa Rap-Rap, Kabupaten Minahasa Selatan, Sulawesi Utara. Data bersih terdiri atas 60 kuadrat yang tersarang dalam enam transek (tiga transek per stasiun). Analisis mencakup kelimpahan total, kelimpahan relatif, frekuensi kehadiran, kekayaan spesies, indeks Shannon, indeks Simpson, dan kemerataan Pielou. Kesamaan komunitas dihitung menggunakan Jaccard, Sørensen, dan Bray–Curtis. Perbedaan komposisi diuji dengan PERMANOVA dan uji dispersi multivariat pada tingkat transek, sedangkan NMDS dan kurva akumulasi digunakan sebagai visualisasi. Sebanyak 1.304 individu dari 22 takson moluska tercatat. Stasiun I memiliki 743 individu dan 20 takson, sedangkan Stasiun II memiliki 561 individu dan 22 takson. Nilai Shannon masing-masing sebesar 2,661 dan 2,763, dengan kemerataan Pielou sebesar 0,888 dan 0,894. Littoraria scabra merupakan spesies paling melimpah pada kedua stasiun. Kesamaan Bray–Curtis mencapai 0,816. PERMANOVA menjelaskan 37,4% variasi komposisi (F = 2,395; p = 0,100), tetapi perbedaannya tidak signifikan karena hanya tersedia tiga transek independen per stasiun. Kedua stasiun memiliki komunitas yang beragam dan merata; Stasiun I memiliki kelimpahan lebih tinggi, sedangkan Stasiun II memiliki kekayaan dan keanekaragaman sedikit lebih tinggi.
Kata kunci: Bray–Curtis; mangrove; moluska; PERMANOVA; Rap-Rap; struktur komunitas
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[1] S. Cannicci, D. Burrows, S. Fratini, T. J. Smith, J. Offenberg, dan F. Dahdouh-Guebas, "Faunal impact on vegetation structure and ecosystem function in mangrove forests: A review," Aquatic Botany, vol. 89, no. 2, hlm. 186-200, 2008. https://doi.org/10.1016/j.aquabot.2008.01.009
[2] S. Zvonareva, Y. Kantor, X. Li, dan T. Britayev, "Long-term monitoring of Gastropoda (Mollusca) fauna in planted mangroves in central Vietnam," Zoological Studies, vol. 54, no. 1, hlm. 39, 2015. https://doi.org/10.1186/s40555-015-0120-0
[3] A. Mansingh, A. Pradhan, dan N. J. Ekka, "Distribution, diversity and abundance of molluscs in the intertidal profile of the Bhitarkanika mangrove ecosystem," Molluscan Research, vol. 41, no. 1, hlm. 7-15, 2021. https://doi.org/10.1080/13235818.2021.1882924
[4] C. Rumisha, H. Shukuru, J. Lyimo, J. D. Maganira, dan A. Nehemia, "Benthic macroinvertebrate assemblages in mangroves and open intertidal areas on the Dar es Salaam coast, Tanzania," African Journal of Aquatic Science, vol. 40, no. 2, hlm. 143-151, 2015. https://doi.org/10.2989/16085914.2015.1051504
[5] D. G. Reid, "The comparative morphology, phylogeny and evolution of the gastropod family littorinidae," Philosophical Transactions of the Royal Society of London. B, Biological Sciences, vol. 324, no. 1220, hlm. 1-110, 1989. https://doi.org/10.1098/rstb.1989.0040
[6] D. G. Reid, P. Dyal, dan S. T. Williams, "Global diversification of mangrove fauna: a molecular phylogeny of Littoraria (Gastropoda: Littorinidae)," Molecular Phylogenetics and Evolution, vol. 55, no. 1, hlm. 185-201, 2010. https://doi.org/10.1016/j.ympev.2009.09.036
[7] D. G. Reid, P. Dyal, P. Lozouet, M. Glaubrecht, dan S. T. Williams, "Mudwhelks and mangroves: The evolutionary history of an ecological association (Gastropoda: Potamididae)," Molecular Phylogenetics and Evolution, vol. 47, no. 2, hlm. 680-699, 2008. https://doi.org/10.1016/j.ympev.2008.01.003
[8] A. C. Alfaro, "Diet of Littoraria scabra, while vertically migrating on mangrove trees: Gut content, fatty acid, and stable isotope analyses," Estuarine, Coastal and Shelf Science, vol. 79, no. 4, hlm. 718-726, 2008. https://doi.org/10.1016/j.ecss.2008.06.016
[9] E. Pape, A. Muthumbi, C. P. Kamanu, dan A. Vanreusel, "Size-dependent distribution and feeding habits of Terebralia palustris in mangrove habitats of Gazi Bay, Kenya," Estuarine, Coastal and Shelf Science, vol. 76, no. 4, hlm. 797-808, 2008. https://doi.org/10.1016/j.ecss.2007.08.007
[10] E. H. Simpson, "Measurement of Diversity," Nature, vol. 163, no. 4148, hlm. 688-688, 1949. https://doi.org/10.1038/163688a0
[11] N. J. Gotelli, dan R. K. Colwell, "Quantifying biodiversity: procedures and pitfalls in the measurement and comparison of species richness," Ecology Letters, vol. 4, no. 4, hlm. 379-391, 2001. https://doi.org/10.1046/j.1461-0248.2001.00230.x
[12] A. Chao, N. J. Gotelli, T. C. Hsieh, E. L. Sander, K. H. Ma, R. K. Colwell, dan A. M. Ellison, "Rarefaction and extrapolation with Hill numbers: a framework for sampling and estimation in species diversity studies," Ecological Monographs, vol. 84, no. 1, hlm. 45-67, 2014. https://doi.org/10.1890/13-0133.1
[13] J. R. Bray, dan J. T. Curtis, "An Ordination of the Upland Forest Communities of Southern Wisconsin," Ecological Monographs, vol. 27, no. 4, hlm. 325-349, 1957. https://doi.org/10.2307/1942268
[14] K. R. Clarke, "Non‐parametric multivariate analyses of changes in community structure," Australian Journal of Ecology, vol. 18, no. 1, hlm. 117-143, 1993. https://doi.org/10.1111/j.1442-9993.1993.tb00438.x
[15] M. J. Anderson, "A new method for non-parametric multivariate analysis of variance," Austral Ecology, vol. 26, no. 1, hlm. 32-46, 2001. https://doi.org/10.1046/j.1442-9993.2001.01070.x
[16] M. J. Anderson, "Distance‐Based Tests for Homogeneity of Multivariate Dispersions," Biometrics, vol. 62, no. 1, hlm. 245-253, 2006. https://doi.org/10.1111/j.1541-0420.2005.00440.x
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