Judul: Evaluasi Pertumbuhan Pohon di Lokasi Revegetasi Lahan Pasca Tambang PT. Vale Indonesia Tbk. Sorowako, Sulawesi Selatan
Abstrak: Kegiatan reklamasi dan revegetasi yang dilakukan oleh perusahaan tambang dalam usaha memperbaiki fungsi lahan yang telah terganggu akibat pembukaan wilayah tidaklah mudah. Evaluasi status pertumbuhan merupakan salah satu cara yang dapat digunakan untuk mengatasi kendala tersebut. Penelitian ini bertujuan untuk mendeskripsikan status pertumbuhan pohon di lahan pasca tambang dan mengevaluasi penyebab gangguan kesehatan pada pertumbuhan pohon di lahan pasca tambang. Metode yang dipakai pada penelitian ini menggunakan objek 4 buah plot yang dilakukan pada 2 lokasi yaitu di Harapan dan di Inalahi. Parameter yang diukur dalam mengidentifikasi status pertumbuhan ini yaitu diameter tanaman, tinggi tanaman, persen tumbuh tanaman, persen kesehatan tanaman dan contoh tanah. Jenis tanaman yang diamati pada penelitian ini yaitu bitti (Vitex coffasus), johar (Senna siamea), kayu angin (Casuarina sp.), dan sengon buto (Enterolobium macrocarpum). Hasil penelitian menunjukkan bahwa tanaman johar memiliki nilai persen tumbuh individu 100%, hal ini berarti tanaman johar memiliki daya hidup yang baik dan bersifat adaptif pada setiap plot pengamatan. Persen tumbuh total dimiliki oleh tanaman sengon buto sebesar 40% di lokasi Harapan dan tanaman johar sebesar 30% di lokasi Inalahi. Tanaman kayu angin di lokasi harapan dan tanaman sengon buto di lokasi Inalahi memiliki nilai persen kesehatan tanaman sebesar 100%. Hal ini menunjukkan kedua tanaman tersebut tahan terhadap gangguan kesehatan di masing-masing lokasi. Gangguan kesehatan tanaman yang terjadi ditunjukkan dengan adanya gejala kekuningan pada daun, bercak-bercak hitam, dan stagnasi. Hasil analisis tanah pada plot yang diamati menunjukkan bahwa adanya nilai unsur hara yang rendah yaitu pada nitrogen (N), kalium (K), fosfor (P), dan kalsium (Ca) sehingga menjadi salah satu penyebab adanya gangguan kesehatan pada tanaman.
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Judul: Kajian hasil-hasil penelitian tentang tingkat pertumbuhan berbagai jenis pohon pada lahan pasca tambang
Abstrak: Mining would give direct negative impact on environmental condition, there are opened soil surface that will increase surface run-off; change on forest ecosystem and forest ecology stability. Objective on post mining area rehabilitation is to construct post mining area fit in the land purpose. Collection results of researches in growth of many trees species is important to know the development of technique and detect the success rate with its factors. The objective of this research to evaluate result on researches collected. This research was carried out by collect and analyze the result of growth on many tree species in post mining area on Laboratorium Bioteknologi Hutan dan Lingkungan ; dan Pusat Penelitian Sumberdaya Hayati dan Bioteknologi (PPSHB) library, University library and Department of Forest Resources Conservation and Ecotourism library at Bogor Agricultural University. Many research resulted there were several tree species which used in rehabilitation post mining area were akasia, lamtoro, gamal, sengon, jarak pagar, pulai, gaharu, nyatoh, kapur naga, mindi, melochia, cemara gunung, nyamplung, ubak, rengkat, leban, and waru . Over tailing in post tin mining area akasia, lamtoro, gamal and sengon well grown with Mycofer and compost treatment beside that jarak pagar seedlings well grown in mixed ameliorant and anorganic fertilizer tratment. Over batu bara tailing, sludge acquition increasing growth of mangium and acacia. Topsoil acquition increasing seedlings growth of pulai species. FMA inoculation and soil amandement treatments increasing grown of agarwood species. Soil amandement treatment given positive effect on seedlings of nyatoh and kapur naga species. Over post gold mining area, combination of active compost and FMA helped mindi species to grown up. Over post nickel mining area, melochia species well grown in fertilizer treatments, beside that grass controlling system helped cemara gunung grown well. Over post tin mining area nyamplung, ubak, rengkat, laban and waru grown up with water splash treatment.
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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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