Judul: Utilization of Jatibarang Landfill Semarang by Cattle egrets (Bubulcus ibis Linnaeus 1758)
Abstrak: Kuntul kerbau (Bubulcus ibis) merupakan salah satu kuntul yang memiliki persebaran luas di dunia termasuk Indonesia. Burung ini memiliki persebaran luas karena dapat memakan jenis mangsa lebih beragam dibandingkan jenis kuntul yang lain. Kuntul kerbau dapat memakan mangsa yang lebih bervariasi sehingga menyebabkan burung ini tidak perlu bergantung terhadap lahan basah, tetapi juga dapat beradaptasi di lahan pertanian, perkotaan, bahkan kondisi lingkungan yang tercemar seperti Tempat Pembuangan Akhir (TPA). Tujuan penelitian ini adalah Menganalisis dinamika kelimpahan kuntul kerbau, Menganalisis pola distribusi kuntul kerbau yang memanfaatkan TPA Jatibarang, dan Mengetahui potensi pakan serangga (larva dan imago) untuk kuntul kerbau. Penelitian ini akan dilaksanakan pada bulan Maret-Juni 2019 di TPA Jatibarang di Jl. Untung Surapati, Kelurahan Kedung Pane, Kecamatan Mijen Semarang, Jawa Tengah. Metode yang digunakan adalah concentration count, plot, garis transek dan swept net. Data yang telah dikumpulkan kemudian diolah untuk mendapatkan nilai indeks keanekaragaman, kelimpahan dan chi-square (Goodnes of fit). Hasil penelitian menujukkan Dinamika kelimpahan kuntul kerbau setiap Zona Aktif berbeda dipengaruhi oleh tempat pembuangan sampah yang aktif sehingga mempengaruhi pakan ditemukan dalam jumlah yang melimpah. Pola distribusi dan tingkat pemanfaatan kuntul kerbau pada ketiga Zona Aktif berbeda karena adanya perbedaan kondisi tempat sampah sehingga memengaruhi jumlah dan jenis serangga (larva dan imago). Zona Aktif 1 digunakan oleh kuntul kerbau secara intensif yaitu mencapai 140-1505 individu. Untuk pemanfaatan kuntul kerbau di Zona Aktif 2 digunakan secara intensif berjumlah 211 individu, semi intensif 31-50 individu dan non intensif 1-22 individu. Sedangkan pada Zona Aktif 3 pemanfaatan intensif digunakan 135-169 individu, semi intensif 11-27 individu dan non intensif terdapat 1-8 individu. TPA Jatibarang dapat mendukung keberlangsungan hidup dengan perkiraan jumlah mencapai 3355 individu pada ketiga Zona Aktif. Dari seluruh Zona Aktif ditemukan potensi pakan untuk kuntul kerbau yaitu larva Diptera dan Coleoptera, serta imago dari lalat (Diptera), belalang (Orthoptera), kupu-kupu (Lepidoptera), capung (Odonata), lebah (Hymenoptera), cocopet (Dermaptera), kumbang (Coleoptera) dan kepik (Hemiptera)., Cattle egret (Bubulcus ibis) is a bird species that has a wide distribution in the world, including in Indonesian. This bird has a wide distribution because it can eat a wider variety of prey than other egrets. Cattle egrets are able to consume more varied preys, making them independent on wetlands and able to adapt on agricultural land, urban areas, and even polluted environmental conditions such as waste landfills. the purpose of this research are analyzed abundance dynamic of cattle egrets, distribution patterns of cattle egrets, and potential food (insects: larvae and imago) for cattle egrets. This research was conducted in March to June 2019 in Jatibarang landfill, located on Untung Surapati Street, Kedung Pane Village, Mijen District, Semarang, Central Java. The Method used concentration count, plots and swept net. Data were analyzed using Shanon-Wiener Index, Index of Abundance and chi-square (Goodnes of fit). The results showed that the dynamics of the abundance of cattle egrets in each Active zone were influenced by Active zone so that the food was found in abundance. The distribution patterns of cattle egrets in the three Active Zones are different due to differences in the conditions of the trash cans, which affect the number and types
Keyword: Active zone, Cattle egrets, Diptera, Food, Insect, Landfill

Judul: Infestation of Fly (Diptera: Cyclorrapha) Ectoparasite on Buffalo (Bubalus Bubalis) in Ragunan Wildlife Park, South Jakarta
Abstrak: Kerbau (Bubalus bubalis) merupakan ternak ruminansia besar yang penting bagi masyarakat Indonesia. Ektoparasit lalat menjadi salah satu penyebab masalah kesehatan pada kerbau selain mengganggu kenyamanan hidup ternak. Penelitian ini bertujuan untuk mengetahui jumlah infestasi ektoparasit lalat dan faktor-faktor aktivitas inang (host) berupa waktu aktivitas, berteduh, dan berkubang yang berhubungan dengan jumlah infestasi ektoparasit lalat pada kerbau. Pengamatan dilakukan terhadap tiga ekor kerbau jantan pada tiga waktu aktivitas, yaitu pagi (06.00-07.00 WIB), siang (11.00-12.00 WIB), dan sore hari (16.00-17.00 WIB), dan di saat yang bersamaan diamati juga apakah kerbau sedang berteduh atau berkubang. Pengamatan ektoparasit lalat pada kerbau dilakukan setiap hari, selama 14 hari, secara eye-catching dengan menggunakan alat bantu teropong. Penghitungan ektoparasit lalat pada masing- masing waktu dilakukan sebanyak tiga kali (ulangan). Hasil penelitian menunjukkan bahwa infestasi lalat pada kerbau didominasi oleh lalat Muscidae sebanyak 92,4% dan sisanya lalat Calliphoridae sebanyak 7,6%. Tingkat infestasi ektoparasit lalat lebih tinggi pada aktivitas di siang hari (47,5%) dibandingkan pada pada (32,2%) dan sore hari (20,3%). Sementara itu, aktivitas berteduh dan berkubang dapat mengurangi jumlah infestasi ektoparasit lalat pada kerbau., Buffalo (Bubalus bubalis) is a large ruminant livestock that is important to the people of Indonesia. Fly ectoparasites are one of the causes of health problems in buffalo besides that can interfere with the comfort of livestock life. This study aimed to determine the number of fly ectoparasite infestation in buffalo and the association of host activities with the infestation. Three male buffaloes in Ragunan Wildlife Park, South Jakarta were observed in three activity times, namely in the morning (06.00-07.00 WIB), in the afternoon (11.00-12.00 WIB), and in the evening (16.00-17.00 WIB); and at the same time, it was also observed whether the buffalo was taking shelter or wallowing. The infestation of fly ectoparasites in buffalo was observed everyday during 14 days in an eye-catching manner using binoculars. The number of fly ectoparasites was counted three times of each time (as repeatation). The results showed that flies in buffalo was dominated by Muscidae flies (92,4%) and the other was Calliphoridae flies (7,6%). The rate of fly ectoparasite infestation was higher during the afternoon activity (47,5%) compared to the morning (32.2%) and the evening (20,3%) activities. Meanwhile, shelter and wallowing activities could reduce the number of fly ectoparasite infestations in buffalo.
Keyword: buffalo, Calliphoridae, ectoparasite flies, Muscidae

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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