Judul: Analisis perubahan penggunaan lahan dan potensi terjadinya lahan kritis di Kabupaten Kulon Progo Daerah Istimewa Yogyakarta
Abstrak: Population growth and development activities have been affecting change of land use. The change of land use, in many case has caused land degradation that lead to formation of critical land. This study aims to (1) analyzed the spatial patterns of land use in Kulon Progo District during 1996 until 2009, (2) analyzed the formation of critical land, (3) analyzed change of land use that affect for critical land. The method used in the study include land use interpretation using landsat image, analyze change of land use by utilizing remote sensing technology. Determining critical land using criteria from forestry according to SK Dirjen RLPS No: SK.167/V-SET/2004. The result of study showed that land use in Kulon Progo District during period 1996-2009 have two type of change: decrease and increase. Land use that decrease include bush: 148 ha, forest: 981 ha, mixed garden: 406 ha, and paddy field: 168 ha. Land use type that increase include residential: 1,101 ha, rain fed field: 74 ha, farmstead: 390 ha, and waduk (water reservoir): 144 ha. During 1996-2009, the land in Kulon Progo District show that area of critical land increase 657 ha from 3,274 ha to 3,931 ha, rather critical land increase 227 ha from 4,025 ha to 4,252 ha. Meanwhile, the area of potential critical land decrease 746 ha from 16,127 ha to 15,381 ha, and un-critical land decrease 138 ha from 34,601 ha to 34,463 ha. The change of land use that cause critical land especially in conservation area is conversion land use of forest to land use non-forest include rain fed field, and farmstead. Rehabilitation of critical land have to consider level of critical land, and the function area so that can be effective and efficient.
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Judul: Analisis data landsat ETM+ untuk kajian geomorfologi dan penutup/penggunaan lahan dan pemanfaatannya untuk pemetaan lahan kritis di Kota Cilegon
Abstrak: Excessive activity of land or soil management could have impacts in the form of soil damage and creation of critical land. Such condition occurs in nearly all areas of Indonesia, including Cilegon city. Land is categorized as critical, if at present, it is not productive or not sufficiently productive, from the point of view of agricultural use, because its management and use has insufficient or no consideration on soil conservation principles. Critical land could disturb ecological balance which results in reduction of environmental quality, and further economic disturbance toward the community. The objectives of this research were: 1) analyzing the data of Landsat ETM+ for study of geomorphology and land cover/land use, 2) identification and mapping of critical land, 3) studying the cause of critical land occurrence in its relation with land form and land use, and 4) providing recommendation for reducing the damage on environmental carrying capacity or for reducing critical land. Method of critical land determination referred to that of Departemen Kehutanan RI, (2003) whereas the calculation was performed by overlay analysis with Geographic Information System (GIS). Based on analysis of Landsat ETM+ Imagery, it was obtained that, combination of band 452 constituted the best combination for geomorphological study, whereas combination of band 542 constituted the best combination for study of land cover/land use. Based on calculation of determining factors for critical land, which comprise land cover/land use, slope, erosion level, and land management condition in the research area, the following results were obtained: 1.977 Ha (10,98%) was categorized as critical land, 639 Ha (3,55%) was categorized as somewhat critical, 5.197 Ha (28,87%) was potentially critical, and 10.189 Ha (56,80%) was non critical land. Factors which had much influence on the occurrence of critical land in the research area were morphology of land form (slope), types of land use (mixed garden/dry land farm), and low quality management of land (soil and water conservation practice). Therefore, critical land area occurred much on land form of denudational volcanic cone of Gunung Gede (KVDG), denudational volcanic cone of Gunung Cidanau (KVDC) and denudational volcanic hill (PVD) which had slopes ranging from steep to very steep. Based on field observation results, impacts of industrial activities (gases and chemical wastes) contributed directly and indirectly to the occurrence of critical land. Research on this problem should be conducted further in other occasion. Key words: Landsat ETM+, Geomorphology, Geographic Information System, Land form, Land use, Critical Land.
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Judul: Natural Pearlescent Pigment Dari Kristal Guanin Sisik Ikan Bandeng (Chanos Chanos)
Abstrak: Pearlescent pigment yang dikenal dengan nama pearl essence atau fish silver merupakan pigmen berwarna keperakan yang memiliki kenampakan seperti mutiara. Natural pearlescent pigment diperoleh dari sisik ikan dengan kandungan guanin 75-97%, dan kini mulai banyak digunakan pada industri personal care dan produk kosmetika. Penelitian ini bertujuan untuk menentukan teknologi ekstraksi natural pearlescent pigment dan karakteristik kualitatif kristal guanin pada sisik ikan bandeng (Chanos chanos). Perlakuan dalam penelitian ini meliputi ekstraksi menggunakan air deionisasi dengan sisik yang dibekukan terlebih dahulu, air deionisasi 10 οC, dimetil sulfoksida 15%, dan 25% (v/v). Hasil spektrum absorbansi UV-Vis menunjukkan kristal guanin merupakan pigmen berwarna putih berdasarkan serapan pada panjang gelombang 200-800 nm. Hasil terbaik diperoleh pada ekstraksi menggunakan air deionisasi dengan sisik beku nilai kristalinitas 68,4%, serapan gugus amina pada 3410 cm-1 dan gugus amida pada1681 cm-1, puncak intensitas 2θ pada sudut 27,7° yang menunjukan identitas dari kristal guanin anhidrat. Tingkat kandungan guanin sebesar 0,0455 ± 0,0033 g (0,46%).
Keyword: Dimetil sulfoksida, guanin, kosmetik, kristalinitas, pearlescent pigment