Struktur Komunitas Gastropoda di Kawasan Mangrove Pantai Kutang Kabupaten Lamongan
Gastropoda merupakan salah satu komunitas yang memanfaatkan ekosistem mangrove sebagai habitatnya. Penelitian ini bertujuan untuk mengidentifikasi spesies gastropoda serta menganalisis struktur komunitas dan karakteristik habitat di kawasan mangrove Pantai Kutang, Kabupaten Lamongan. Sampling dilakukan saat surut terjauh menggunakan metode transek kuadran. Identifikasi spesies berdasarkan karakter morfologi. Struktur komunitas dianalisis secara deskriptif kuantitatif berdasarkan tujuh parameter meliputi kepadatan (D), kelimpahan relatif (KR%), frekuensi relatif (FR%), indeks nilai penting (INP%), indeks keanekaragaman (H’), indeks dominansi (C), dan indeks kemerataan (E). Berdasarkan penelitian ini diperoleh 30 spesies yang termasuk dalam 17 famili. Spesies Littoraria articulata dari famili Littorinidae menunjukkan nilai kepadatan, kelimpahan relatif, frekuensi relatif, dan indeks nilai penting tertinggi, yaitu berturut-turut 1,83 individu/m2; 19,88%; 7,59%; dan 27,47%. Indeks keanekaragaman tergolong sedang (H’=1–3), indeks dominansi (C<0,5) menunjukkan tidak adanya dominansi antarspesies, dan indeks kemerataan (E=0,6–1) tergolong tinggi menunjukkan persebaran antarspesies relatif seimbang. Dapat disimpulkan bahwa struktur komunitas gastropoda di Pantai Kutang tergolong sedang, Littoraria articulata memiliki kemelimpahan tertinggi dan karakteristik habitat gastropoda di ekosistem mangrove adalah substrat lumpur berpasir meliputi suhu, pH, dan salinitas masing-masing 29±0,00°C; 7,86±0,00; dan 3±0,58‰.
Kata kunci: Littoraria articulata; siput; Turbo petholatus; zona intertidal
Gastropods are one of the communities that utilize the mangrove ecosystem as their habitat. This study aimed to identify the type of gastropod also analyze the community structure and habitat characteristics in the mangrove area of Kutang Beach, Lamongan Regency. Sampling was conducted during the lowest tide using the quadrant-transect method. Species identification based on morphological characters. Community structure was analyzed descriptive-quantitatively based on seven parameters, namely density (D), relative abundance (KR%), relative frequency (FR%), importance value index (INP%), the diversity index (H’), dominance index (C), and evenness index (E). Based on this research obtained 30 species among 17 families, with Littoraria articulata species from the family Littorinidae showing the highest density (D=1.83 individuals/m2); relative abundance (KR=19.88%); relative frequency (FR=7.59%); and importance value index (INP=27.47%). The diversity index was moderate (H’=1–3), the dominance index (C<0.5) indicates the absence of dominance between species, and the evenness index (E=0.6–1) was high, indicating a relatively balanced distribution between species. It can be concluded that the gastropod community structure in Kutang Beach is moderate, Littoraria articulata has the highest abundance and the characteristics of gastropod habitat in mangrove ecosystems are sandy mud substrates including temperature, pH, and salinity 29±0.00°C; 7.86±0.00; and 3±0.58‰.
Keywords: intertidal zone; Littoraria articulata; snail; Turbo petholatus