DOI: https://doi.org/10.14710/ijfst.15.1.1-10

KARAKTERISTIK LINGKUNGAN PENENTU DISTRIBUSI DAN KEPADATAN FAUNA MAKRO BENTIK SERTA HUBUNGANNYA: STUDI KASUS GASTROPODA DAN KEPITING BRACHYURA DI KAWASAN REBOISASI MANGROVE KEPULAUAN SERIBU

*Syahrial Syahrial  -  Belukap Mangrove Club, Indonesia
Fahriansyah Fahriansyah  -  Belukap Mangrove Club, Indonesia
Anna Lilian  -  Belukap Mangrove Club, Indonesia
Arbaeyah Arbaeyah  -  Belukap Mangrove Club, Indonesia
Cahyani Fitrah Tanjung  -  Belukap Mangrove Club, Indonesia
Nila Sari Lubis  -  Belukap Mangrove Club, Indonesia

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Abstract

Hutan mangrove memiliki lingkungan yang sangat kompleks, dimana di dalam dan antar lokasi habitat mangrove saling berbeda. Kajian karakteristik lingkungan penentu distribusi dan kepadatan fauna makro bentik serta hubungannya (studi kasus gastropoda dan kepiting brachyura di kawasan reboisasi mangrove Kepulauan Seribu) telah dilakukan pada bulan Maret 2014. Hal ini bertujuan untuk mengetahui faktor-faktor lingkungan yang berperan terhadap distribusi dan kepadatan gastropoda maupun kepiting brachyura serta untuk mengetahui hubungan antara karakteristik lingkungan dengan distribusi dan kepadatan gastropoda maupun kepiting brachyura di kawasan reboisasi mangrove Kepulauan Seribu. Pengukuran karakteristik lingkungan dilakukan dengan cara insitu, sedangkan data gastropoda dan kepiting brachyura dikumpulkan dengan membuat transek garis dan plot yang ditarik dari titik acuan (tegakan mangrove terluar) dan tegak lurus garis pantai sampai ke daratan. Faktor-faktor lingkungan yang menentukan distribusi dan kepadatan gastropoda maupun kepiting brachyura dianalisis menggunakan Principal Component Analysis (PCA), sedangkan hubungannya digunakan analisis regresi linier sederhana. Hasil kajian memperlihatkan bahwa karakteristik lingkungan yang paling menentukan distribusi dan kepadatan gastropoda maupun kepiting brachyura di kawasan reboisasi mangrove Kepulauan Seribu adalah parameter pH. Hal ini mengindikasikan bahwa semakin tinggi konsentrasi pH perairan, maka kepadatan gastropoda maupun kepiting brachyura juga semakin tinggi. Begitu sebaliknya, semakin rendah konsentrasi pH perairan, maka kepadatan gastropoda dan kepiting brachyura juga semakin menurun.

Mangrove forests have a very complex environment, where in and between locations mangrove habitats are different. The study of environmental characteristics determining the distribution and density of benthic macrofauna and their relationship (a case study of gastropods and crab brachyurans in the Seribu Islands mangrove reforestation area) was conducted in March 2014. The research aims to determine environmental factors that contribute to the distribution and density of gastropods and brachyurans crabs and to determine the relationship between environmental characteristics and the distribution and density of gastropods and crab brachyurans in the Seribu Islands mangrove reforestation area. Measurements of environmental characteristics were carried out by insitu method, while data on gastropods and crab brachyurans were collected by making line transects and plots drawn from the reference point (outermost mangrove stands) and perpendicular to the coastline to the mainland. Environmental factors that determine the distribution and density of gastropods and crab brachyurans were analyzed using the Principle Component Analysis (PCA), while the relationship used simple linear regression analysis. The results of the study show that the environmental characteristics that most determine the distribution and density of gastropods and crab brachyurans in the mangrove reforestation area of the Seribu Islands are pH parameters. This indicates that the higher the concentration of water pH, the higher the density of gastropods and crab brachyurans. On the contrary, the lower the concentration of water pH, the density of gastropods and crab brachyurans also decreases.

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Keywords: Karakteristik Lingkungan; Gastropoda; Kepiting Brachyura; Mangrove; Reboisasi; Kepulauan Seribu

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