No abstract

Roach populations from different parts of the network of the French Upper Rhone and from Lake Geneva were examined. Several populations were discriminated by the electrophoresis of 16 enzymes coded for by 28 gene loci.90% of the overall genetic variation was due to intrapopulation variation. Some affinity was found between the populations of Lake Geneva and the Rhone immediately downstream, but the stocks of the Rhone farther down proved to be clearly distinct from these (genetic distance D = 0.048) and probably included several independently reproducing populations. One of these populations was only found in the channel, others inhabited a side arm (D between them = 0.035) or succeeded each other in it, presumably in connection with spawning migrations. R&urn6Plusieurs organes de gardons provenant du Lac LCman et de diverses parties du reseau fluvial du RhBne ont CtC trait& par tlectrophorese.Seize systemes enzymatiques ont CtC analyses, codes par 28 loci. La variabilite genetique du gardon est dominee a 90% par la variabilite intrapopulation.Cependant, l'examen du dendrogramme des affinites genetiques fait apparaitre un premier groupe populationnel dans le LCman et une partie du Rh6ne en aval, s&pare des autres par une distance (D = 0,048). Le reste est un groupe hethogene, comprenant plusieurs populations dont il est probable qu'elles se reproduisent independamment les unes des autres, certaines typiques du chenal, d'autres d'un bras mort (D = 0,035 entre elles), d'autres enf'm dont on peut penser qu'elles se succedent dans le bras mort a l'epoque de la reproduction.

ABSTRAK Teknologi bioflok merupakan salah satu alternatif untuk mengatasi masalah kualitas air lingkungan budidaya yang diadaptasi dari teknik pengelolaan limbah secara konvensional. Tujuan dari penelitian ini adalah mengkaji pemeliharaan benih ikan lele dengan penerapan bioflok dari beberapa produk konsorsium, diantaranya bakteri Bacillus megaterium (BM), Supernit (SP), Depok 165 (DP165), Kayajaga (KJ) dengan membandingkan pemeliharaan tanpa teknologi bioflok untuk perbaikan kualitas air. Hasil penelitian dan uji statistik menunjukkan bahwa, konsentrasi TAN terendah oleh probiotik KJ sebesar 2,56 mg L-1 sedangkan kontrol sebesar 5,47 mg L-1 dan konsorsium bakteri memberikan pengaruh terhadap TAN (p<0,05). Konsentrasi amonia terendah oleh probiotik KJ sebesar 0,0001853 mg L-1 sedangkan kontrol sebesar 0,0003973 mg L-1 , dan konsorsium bakteri tidak memberikan pengaruh terhadap amonia (p>0,05). Konsentrasi nitrit terendah oleh probiotik BM sebesar 0,065 mg L-1 sedangkan kontrol sebesar 0,124 mg L-1 , dan konsorsium bakteri memberikan pengaruh terhadap nitrit (p<0,05). Konsentrasi nitrat terendah oleh probiotik BM sebesar 1,203 mg L-1 sedangkan kontrol sebesar 3,437 mg L-1 , dan konsorsium bakteri memberikan pengaruh terhadap nitrat (p<0,05). Konsorsium bakteri memberikan pengaruh terhadap COD (p<0,005) akan tetapi seluruh perlakuan konsorsium memiliki nilai konsentrasi lebih tinggi yang berkisar antara 430475 mg L-1 dibandingkan kontrol. Dari sini ditarik kesimpulan bahwa penerapan bioflok dapat memperbaiki kualitas air, dimana hal ini terlihat dari penurunan nilai konsentrasi parameter TAN, amonia, nitrit, dan nitrat.

Abstract. Zamroni Y, Soewardi K, Suryobroto B, Jaafar Z. 2016. Short Communication: Conservation of mangrove gobies in Lesser Sunda Islands, Indonesia. Biodiversitas 17: 553-557. Ecosystems goods and services from mangrove forests are especially vital to coastal communities. Yet mangrove areas continue to be deforested at unprecedented rates. Using gobioid fishes associated with mangrove forests as focal organisms, we assessed their diversity in 14 selected sites within the Lesser Sunda group of islands. We applied Correspondence analysis to determine the relationships between ecosystems based on the occurrence of these fishes and complementarity analysis to identify the minimum number of sites to conserve maximum diversity based on a rarity algorithm. We recovered 55 gobioid fish species at these mangrove areas, and proposed six mangrove areas within the Lesser Sunda group of islands as areas of conservation priority: Loh Sebita, Oebelo, Bipolo, Lembar Bay, Selindungan, and Kawangu. The three former areas are already within protected zones while the remaining latter three areas are at present unprotected. The argument for the conservation of these three remaining areas is a compelling one, based on our data (diversity of gobioid fishes), and corroborating data (diversity of corals, reef fishes, stomatopods, seagrasses, and marine birds) from other studies.