Struktur Komunitas Larva Ikan Pada Area Mangrove Dengan Tipe Perakaran Berbeda Di Pesisir Labuhan, Madura

Kompleksitas tipe perakaran dan naungan pada mangrove diketahui memberi efek positif bagi ikan baik larva ikan, juvenil dan ikan dewasa. Akan tetapi, belum diketahui apakah kompleksitas akar magrove tersebut juga berpengaruh positif bagi larva ikan, termasuk di pesisir Labuhan, Madura yang diproyeksikan sebagai suatu area konservasi mangrove. Penelitian mengenai struktur komunitas larva ikan pada mangrove dengan tipe perakaran berbeda di lokasi tersebut telah dilaksanakan pada periode Maret-April. Sampel larva ikan dikoleksi menggunakan plankton net dengan mesh-size 0,150 dan 0,265 mm pada enam lokasi yang memepresentasikan tipe perakaran yang berbeda (akar tunjang, pneumathopore, campuran akar tunjang dan pneumathopore serta area tanpa vegetasi). Variabel lingkungan yang diukur meliputi suhu, salinitas, pH, kecepatan arus, kekeruhan dan kadar oksigen terlarut . Diakhir penelitian teridentifikasi enam famili larva ikan yaitu Gobiidae, Blenniidae, Carangidae, Apogonidae, Pomocentridae dan Ambassidae .Gobiidae merupakan famili dengan kelimpahan tertinggi dan tersebar pada semua lokasi. Hasil Anova dua-arah yang dilanjutkan dengan uji Tukey pada p=0,05 menunjukkan bahwa faktor lokasi dan waktu pengambilan sampel serta interajsi antara kedua fator tersebut memberikan perbedaan yang signifikan terhadap kelimpahan namun tidak memberikan perbedaan untuk veriabel jumlah taksa. Area mangrove Rhizopora sp yang berakar tunjang memiliki kelimpahan dan jumlah famili larva ikan tertinggi, mengindikasikan adanya pengaruh kompleksitas akar mangrove terhadap komunitas larva ikan. Hasil ordinasi menggunakan analisis kanonik menunjukkan adanya kecenderungan sebaran taksa-taksa larva ikan pada lokasi-lokasi tertentu. ================================================================================================================== Root complexity and shading are well known to give positive correlation for both juveniles and adult fishes. However, it is remain unclear whether that complexity would affect the community of fish larvae. This study aimed to address the question, espescially in mangrove area in coastal area in Sepulu, Madura which projected as a mangrove sanctuary in the future. Sampling periods are from March to May 2016. The samples of fish larvae were collected by plankton net (mesh size 0,150 and 0,265mm) from six different locations that representing different root types (stilt root, pneumatophore, combination of stlit root-pneumatophore and unvegetated area). Water temperature, salinitas, pH, current velocity, turbidity, and level of dissolved oxygen were measured as ambient environtmental variables. As the result, six families were identified, namely Gobiidae, Blenniidae, Pomacentridae, Carangidae, Apogonidae and Ambassidae, respectively. Gobiidae seems to be the most abundant and widely dispersed in the area. Result of two way Anova and Tukey HSD (both at p=0,05) indicate that there were significant difference in the larval abundance regarding locations, sampling periods and interaction of both factors. As number of taxa, significant difference occured only from factors of location and sampling periods, but not for interaction of both factors. Highest larval abundance and number of taxa occured in Rhizopora sp (with stlit root), indicating that root complexity would affect the community of fish larvae. Ordination by canonical analysis shows that different taxa of the fish larvae are tend to be distributed on different locatio