Judul: Perencanaan pengembangan alternatif usahatani berbasis kelapa untuk pembangunan pertanian berkelanjutan di SUB DAS Molompar Kabupaten Minahasa Tenggara
Abstrak: Low land productivity is the main problem of upland farming systems in Sub DAS Molompar. This is likely due to inadequate agrotechnologies and soil and water corservation technigues on upland farming systems. Therefore, it is presumed that the existing upland farming systems is not sustainable. Objectives of this research were 1) to identify and to evaluate land use characteristics and agrotechnology of coconut based farming system, (2) to develop alternatives of coconut based farming system. Identification and upland coconut based farming systems were conducted useing survey method, evaluation of land use was conducted through land capability evaluation using method of Klingebiel and Montgomery, and developing alternatives of improved upland coconut based farming systems were carried out using USLE model. Results of this research showed that land use in the area coconut based was dominanated by underbrush, fallowed by forest and mixed garden with undulating topography and high erosion as limiting factors. All type of land-uses are generally suited to their land capability classes. Upland farming systems were generally dominated by coconutbased farming systems with predicted erosion rate was ranged from 1.6-93.5 tons/ha/year; it was much greater than the local tolerable soil loss 27.00-36.00 tons/ha/year. Total farmers income on upland farming systems was much lower Rp 4.717.500-12.119.500/household/yr than the income that can suppart worth life living standard Rp 17.200.000/household/yr. Improved coconut-based farming systems with appropriate agrotechnologies including balance fertilization, countruction of ridge and traditional terraces as well as raising livestocks can decrease erosion to less than local tolerable soil loss and to increase farmers income to more than worth life living standard.
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Judul: Perencanaan penggunaan lahan dan pengembangan usahatani berbasis kopi untuk sistem pertanian berkelanjutan di DAS Ketahun Hulu Provinsi Bengkulu
Abstrak: Ketahun Hulu watershed is part of Ketahun watershed, administratively it is mainly located in Lebong district and a small portion of it is located in North Bengkulu and Rejang Lebong districts of Bengkulu province. This study was aimed to identify landuse and agrotechnology characteristics in Ketahun Hulu watershed, and to arrange land use planning and coffee based farming development for sustainable agricultural systems in the Ketahun Hulu watershed. To achieve a sustainable agriculture, there are 3 (three) indicators that should be fulfilled : a) total farmer’s income should be high enough support a life worth living, b) erosion should be less than tolerable soil loss (ETol), c) agrotechnologies should be acceptable and replicable to the farmers. This study was focus on intensive observation sites covering 14,844 hectares located in one of sub watershed that represent characteristics of the watershed. Land capability was evaluated using Klingebiel and Montgomery method, erosion was predicted using USLE equation developed by Wishmeier and Smith (1978), and farming income was analyzed using cash flow analysis method. Results of this research showed that predicted erosion in the existing cropping pattern and agrotechnologies in Ketahun Hulu watershed generally greater than ETol; it ranged from 2,47 – 683,18 tons/hectare/year while ETol was ranged from 13,45 – 36,38 tons/hectare/year. Total incomes of farmers were much lower than a decent income (Rp. 18.000.000,-/householder/year). Alternative agrotechnologies to meet the indicators of sustainable agricultural systems were recommended with two alternatives. To increase farmer’s income to meet the income of decent living, the source of income such as livestock was introduced in to the existing farming systems. Simulation of agrotechnologies show that alternatives of agrotechnology can reduce erosion to lower than ETol and to increase farmer’s income up to a decent income. Alternative agrotechnolgy 1 which consisted of grass strip plus litter mulch, fertilizer and livestock including 30 chickens and 5 goats can reduce erosion to lower than ETol (2,45 – 22,77 tons/hectares/year) and increase farmer’s income up to a decent living (Rp. 18.855.000,- to Rp. 24.915.000,-/householder/year). Alternative agrotechnology 2 which consisted ridge terrace plus litter mulch, fertilizer and livestock including 30 chickens and 5 goats can reduce erosion to lower than ETol (2,47 – 22,77 tons/hectares/year) and increase farmer’s income up to a decent living (Rp. 18.635.000,- to Rp. 24.695.000,-/householder/year). Spatial planning of recommended agrotechnologies was extrapolated into the watershed in Ketahun Hulu Watershed.
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Judul: Closed Knight’s Tour pada Papan Catur Berbentuk Persegi Panjang dengan Ukuran Maksimal 8 × 8
Abstrak: Closed Knight’s Tour merupakan langkah kuda yang mengunjungi setiap kotak pada papan catur tepat satu kali dengan langkah kuda berawal dan berakhir pada kotak yang sama. Graf yang terbentuk dari closed knight’s tour dinotasikan sebagai graf G(m,n), dengan m adalah banyaknya baris dan n adalah banyaknya kolom. Graf tersebut memuat Hamiltonian cycle. Sebuah graf terhubung G adalah graf bipartite jika dan hanya jika graf tersebut tidak memiliki cycle dengan panjang ganjil. Papan catur yang memenuhi syarat cukup untuk memiliki closed knight’s tour adalah papan catur berukuran 5 × 6, 5 × 8, 6 × 6, 6 × 7, 6 × 8, 7 × 8, dan 8 × 8.
Keyword: bipartite, closed knight’s tour, hamiltonian cycle, knight’s tour, teori graf