Judul: Dampak Pertambangan Batu Granit terhadap Sifat Fisik, Sifat Kimia, dan Sifat Biologi Tanah di Areal Hutan Lindung PT. Karimun Granit Kabupaten Karimun Propinsi Kepulauan Riau
Abstrak: Introduction. Indonesia have variated potency of nature resources that indigenous to forest. Besides management of forest, there is other activity that goes on in forest area that is mining activity. Mining Activity generaly conducted in nature forest, and even protected forest. Mining Activity of course can destroy forest ecosystem that opened for made areal mining. Mining Activity cause vegetation and land damage that affect erosion and sedimentation. Mining also can cause loss of land fertility at ex areal mine. In consequence, its needed research about the impact of mining . Specifically for granite mining that conducted PT. Karimun Granite in Sub-province Karimun, Province Kepulauan Riau, that reported has caused various of landscape and land damage in the mining areal. Materials and Method. This Research uses data of physical characteristic analysis, chemistry and biology of protected forest area land PT. Karimun Granit Sub-province Karimun, Province Kepulauan Riau. Research Method as used in this research is by purposive sampling, that location has been determined by Tim KementrianLingkungan Hidup. Data of physical analysis, chemistry and biology characteristic are compared to every location to analize the level of change at each of land characteristic value. Analysis of land characteristic is conducted to know the characteristic of physical, chemistry, and land biology at research location. Analysis of Variance (ANOVA) by F test to variable perceived, conducted to know physical denaturing, chemistry and land biology after activity of granite mining. If f-count reach > F tables (value of reality opportunity < 0.05) or granite mining has an effect on reality, then conducted test continues to compare the middle value treatment. The test continues that used is Tukey test. Result and Discussion. Base value of analysis result characteristic of physical, chemistry, and land biology is known that at the three of location that is nature forest, dig land, and erotion land value each characteristic of land experiences of change either degradation or improvement. Then base testing result by F test, characteristic of land physical are not influenced manifestly by granite mining. Whereas for characteristic of chemistry and biology of some of which land is influenced manifestly by granite mining that is C-Organic, N-total, Mg, Na, KTK, Mn, and totalize mikroorganisme land. Result continues Tukey test for land characteristics referred as indicate that value at dig land and erotion land differ reality by value at nature forest. Conclusion. Activity of granite mining causes change the physical characteristic of land, that shown by the increase of bulk density, and degradation of land porosity, water availabilty, and permeability. In other hand, activity of granite mining causes change at characteristic of land chemistry that shown by increasing of pH, Fe, and Zn and degradation of C-organic content, KTK, N-total, P-Bray, K, Ca, Mg, Na. And then, activity of granite mining causes change at characteristic of land biology that is shown by increase of fungi land, totalize solute P bacterium, and totalize land respiration, and degradation of land mikroorganisme.
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Judul: Kajian Sifat Fisik, Sifat Kimia dan Sifat Biologi Tanah Paska Tambang Galian C pada Tiga Penutupan Lahan (Studi Kasus Pertambangan Pasir (Galian C) di Desa Gumulung Tonggoh, Kecamatan Astanajapura, Kabupaten Cirebon, Provinsi Jawa Barat)
Abstrak: Introduction: Indonesia is a country that has abundance natural resources like dig substance, mineral, petroleum, gas, flora and fauna residing in the land. Sand is one of dig substance which is quite abundant on this country. This dig substance is usually exploited by open mining. Open mining has benefits for building materials, local’s occupations and increasing the local income. However, Open mining has negative impacts for wildlife, land cover loss, and land quality degradation. Because of these negative impacts, it needs to conduct a research about the effect of sand mining toward physical, chemistry, and biology soil characteristics. Methodology: Research was conducted on sands open mining at Gumulung Tonggoh village, Astanajapura district, Cirebon regency, West Java province. Instrument that used for this research are hoe, plastic poke, camera, calculator, SPSS 13.0 software. The data are primary data for land structure and secondary data for soil’s physical, chemistry, and biology characteristic. The method of this research was survey with purposive sampling which has done by ministry of state environment year 2006 and statistical data on site. Then conducted some statistical F test on soil characteristic to know whether there is significant or not from sand mining activity and after continued by Duncan’s test, locations that has significant difference can be showed. Result and Discussion: Sand Mining activities have altered soil’s physical, chemical, biology characteristics on after-mining sites in Gumulung Tonggoh village. It has been proved by significant change of bulk density value, low porosity, and rapid decrease of drainage pore. Soil’s chemical characteristic has significant change as well. There is some soil characteristic that is influenced by mining activities like change cation capability (KTK), calcium and magnesium decreasing and the increasing of phosphor inside the soil. For soil biology characteristic, only amount of soil’s microorganism that influenced by sand mining activities. It has been analyzed by significant value and have significant value < 0,05 actual rate as a result. Permeability, pH, BO, nitrogen, kalium, natrium, amount of soil’s fungi, phosphate-dissolved bacteria and soil respiration have change but not really significant as a results of statistic test. The changes of soil characteristic on this research happens because soil’s condensation as a result of using of heavy instruments. Conclusion: Sand Mining activity ( Dig C) in Gumulung Tonggoh village have altered some characteristic changes of soil’s physical, chemical and biology characteristic because of land condensation by heavy equipment use on mining activity. Based on statistical test, character that significant is bulk density value, land porosity, drainage pore very quickly, KTK, phosphor, calcium, magnesium and amount of soil microorganism. Characteristic changes on soil characteristics affect one and each other.
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Judul: Best Difference Equation Aproximation to Duffing 's Equation
Abstrak: Persamaan Duffing merupakan persamaan yang sering muncul sebagai model masalah sistem ayun mekanis atau pada masalah rangkaian listrik. Umumnya penyelesaian persamaan ini secara numerik memberikan hampiran dengan gala! yang tinggi, seperti dengan metode Runge-Kutta. Tulisan ini mengkonstruksi suatu persamaan beda untuk menghampiri persamaan Duffing tersebut. Penyelesaian dari persamaan beda ini melibatkan fungsi-fungsi eliptik Jacobi. Berdasarkan penyelesaian ini diperoleh basil bahwa penyelesaian hampirannya persis sama dengan penyelesaian analitiknya. Penyelesaian analitik yang diperolehjuga melibalkan fungsi-fungsi eliptik Jacobi.
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