STRUKTUR TINGKAT TROFIK KOMUNITAS IKAN DI WADUK WADASLINTANG KABUPATEN WONOSOBO, JAWA TENGAH
Authors: Fatah Khoirul , Adjie Susilo 
Published: October 2016

Waduk Wadas lintang memiliki potensi perikanan yang cukup besar baik perikanan tangkap maupun perikanan budidaya. Kegiatan penangkapan ikan di waduk Wadaslintang saat ini sudah cukup tinggi, yang akan berdampak langsung pada struktur komunitas ikan yang menyebabkan pergeseran pola hubungan antara pemangsa,mangsa atau pesaing pada berbagai tingkat trofik. Tujuan penelitian ini untukmengetahui pola hubungan antar kelompok ikan berdasarkan tingkat trofik dari tingkat trofik terendah sampai kepada ikan karnivor, sehingga diperoleh gambaran peran kelompok ikan dalam komunitas. Penelitian ini dilaksanakan pada bulan April, Juni, September dan Nopember 2013 di perairan waduk Wadaslintang. Analisa data mencakup komposisi hasil tangkapan dan kebiasaan makan ikan serta tingkat trofik komunitas ikan. Analisis sidik ragam untuk mengetahui perbedaan antar tingkat trofik. Ikan contoh diperoleh dari nelayan dengan alat tangkap jaring, mulai dari ukuran 0,75 – 4,5 inchi. Hasil penelitian diketemukan sebanyak 15 jenis ikan yang didominasi oleh ikan nila dengan persentase berat mencapai 56,45%. Struktur komunitas ikan di perairan waduk Wadaslintang tersusun atas tiga kelompok tingkat trofik yaitu ikan patin, nila, tawes dan nilem mempunyai jenjang trofik terendah (<2,5), ikan bader dan brek mempunyai nilai jenjang trofik sedang (2,5 – 3,49) dan ikan beong, betutu, palung dan lelemempunyai nilai jenjang trofik tertinggi (>3,5). Kelompok ikan pada tingkat trofik rendah < 2,5 sangat penting dalam menyokong komunitas ikan di perairan waduk Wadaslintang karena akan mempengaruhi kelompok ikan dengan tingkat trofik tinggi.Wadaslintang reservoirs was considered have high potential for fisheries and aquaculture. Fishing Activities in the Wadaslintang reservoir is currently quite high, which may gave a direct impact on the trophic levels structure of fish community and would change composition of predators, preys, and competitors on various trophik levels. The objective of research was focused on the pattern of relationship among trophic groups from the lowest level of trophic to the highest level of carnivorous fish, to find out the role of each fish group in the community. This research was carried out in April, June, September and November 2013 at Wadaslintang reservoir waters. The recorded data were analysed to find out the composition of the fish, feeding habits and trophic levels, and followed by statistical analysis of variance to evaluate the difference among trophic level. Fish samples obtained from a capture tool gillnets, ranging from size 0.75 – 4.5 inches. The results shows that Wadaslintang Reservoir was habited by 15 species of fish where Nile Tilapiais is the dominance species with percentage weight is 56,45%. The structure of fish communities in the water of the Wadaslintang reservoir composed of three groups, namely trophic level of sutchi catfish, nile tilapia, silver barb and nilemhad the lowest trophic levels (< 2.5), barb and javaen barb had value trophic level moderat (2.5-3.49) and catfish, marble goby, hampala barb and walking catfish had the highest trophic level values (>3.5). Fish group on trophic level < 2.5 levels is very important group in supporting good community structure in Wadaslintang reservoir as a way to sustainability of populaion oh the other groups with higher trophic level.