Early Identification for Prospective Housing Area in the Landslide Potential Zone

Identification of area for prospective housing before construction is much needed, especially area with a steep slope and young volcanic that have landslide risk. The risk of landslides is not only caused by high rainfall or steep slope but can be caused by shocks due to earthquakes. It is necessary to identify the rock types in the prospective housing near Mount Salak in Cijeruk area, Bogor Regency. The purpose of this research is early identification types of rocks, soils, and potential of a landslide in prospective housing by geological and soil survey methods. The geological survey method used is to identify morphometry and lithology specially landslide, whereas soil survey identifies soil characteristics. According to results of research, morphometry at prospective housing is included moderately until steep slope category. Steep slopes potentially cause landslides with debris avalanche type. Characteristics of soil at Cijeruk support it has an of high coefficient of linear extensibility; this condition affects the shallow foundation movement. Therefore needs additional material so that the coefficient of linear extensibility value becomes low. The soil in this location comes from volcanic activity with tuff and lapilli types, sometimes found pebbles until boulder, and they are not lithification. If the location of the housing is exposed to an earthquake with a scale of 5 SR, it would be high shocks and areas with steep slopes would cause landslides. For maintenance from landslides, retaining walls need to be made with the type of gravity wall and cantilever wall. The distance between the retaining wall and housing is 15 meters. The type of foundation to be used is the foundation of the spread footing.   Keywords: prospective housing, landslide potential, Cijeruk

ANALISIS KESELARASAN ANTARA PENGGUNAAN LAHAN SAAT INI DENGAN ALOKASI RUANG DAN STATUS LAHAN (STUDI KASUS KABUPATEN BOGOR BAGIAN BARAT)

Pemekaran wilayah sudah banyak dilakukan dan tampaknya akan terus terjadi, seperti wacana pemekaran Kabupaten Bogor bagian Barat. Pembentukan wilayah otonomi baru memerlukan persiapan yang penting. Antara lain dalam level pemanfaatan sumberdaya fisik wilayah. Analisis keselarasan antara penggunaan lahan saat ini dengan alokasi ruang dan status lahan sangat relevan dengan rencana pemekaran suatu wilayah. Informasi yang diperoleh merupakan dasar dalam penataan ruang wilayah baru. Analisis tumpangtindih antara penggunaan lahan saat ini, alokasi ruang yang ada dan status lahan di wilayah Kabupaten Bogor bagian Barat telah dilakukan. Hasilnya menjelaskan bahwa terdapat ketidakserasian antara Kawasan Hutan Konservasi karena adanya penggunaan lahan lain selain hutan yaitu: kebun campuran, permukiman, perkebunan, pertambangan, sawah dan tegalan dengan status lahan Hak Guna Usaha dan Hak Milik. Dalam Kawasan Perkebunan status Hak Guna Usaha terdapat aktivitas masyarakat bercocok tanam. Kebun campuran hasil dari aktivitas masyarakat yang dijumpai pada seluruh alokasi ruang dan status lahan yang berbeda dengan luas yang beragam