ESTIMASI POTENSI AIRTANAH MELALUI PENDEKATAN TIPOLOGI BENTUKLAHAN WILAYAH BOGOR PROVINSI JAWA BARAT - Sumartoyo, Sumartoyo (MAJALAH ILMIAH GLOBE, 2010)
Wilayah Bogor terdiri atas satuan-satuan bentuklahan hasil dari proses geologi sejakperiode Pra Tersier hingga Kuarter. Berbagai macam bentuklahan ditempati penduduk, dikelola dan dimanfaatkan sebagai tempat mata penghidupan. Salah satu kebutuhan pokok penduduk adalah air, tetapi belum semua orang mengetahui kondisi air di tempat hidupnya. Kajian estimasi potensi air tanah melalui tipologi pendekatan bentuklahan bertujuan mengetahui sebaran dan kondisi airtanah setiap bentuklahan. Pendekatannya melalui karakteristik akuifer pada setiap litologi penyusun satuan bentuklahan. Pendekatan geomorfologi sebagai dasar klasifikasi bentuklahan berdasarkan bentukan asalnya. Kedudukan dan sebaran setiap satuan bentuklahan digunakan sebagai satuan pemetaan airtanah. Hasil penelitian menunjukkan sebaran bentukan asal volkanik 51,5 % luas daerah, bentukan asal struktural 31 %, karstik 6,5 %, dan fluvial 11,5 %. Wilayah Bogor terdiri dari 50 macam bentuklahan, tersebar 29,5 % di pegunungan, 59 % di perbukitan, dan 11,5 % di dataran. Hasil kajian menunjukkan pada pegunungan dan perbukitan terdapat sebaran 17 %potensi airtanah langka atau sarang. Potensi airtanah setempat produktif tersebar di 15 % dari luas wilayah, sedangkan produktif kecil tersebar di 0,5 %. Airtanah produktif sedang dan setempat tersebar di 16,5 %, produktif sedang dan luas tersebar di 27 %, sementara airtanah produktif tinggi dan luas tersebar di 24 % luas wilayah Bogor. Estimasi perhitungan resapan air dari sumber air hujan setiap tahun 6.678,89 x 106 m³/tahun tersebar di pegunungan 123.656.694,79 m³/tahun, dan 126.665.275,44 m³/tahun di daerah perbukitan, sementara di dataran aluvial 37.983.987,77 m³/tahun.Kata Kunci : Bentuklahan, Satuan Pemetaan, Potensi AirtanahABSTRACTLandform is part of the landscape in Bogor Regency. The landform was formed through geologic processes since before tertiary up to quaternary periods. Various kinds of landforms are occupied by residents, managed and used as a source of living. One of the basic human necessities is water, however not everyone knows the water quality in the area where they live. Assessment of water potential estimation through typological approach of landforms was aimed to know the distribution and condition of groundwater for every landform. Analysis was done for aquifer characteristics of every lithology of the landforms. Geomorphological approach was used as a base of landform classification according to the original formation.Position and distribution of each landform was used as the unit for groundwater mapping. The result of this research indicated that vulcanic morphogenesis was distributed in 51.5% of Bogor Regency, structural morphogenesis covered 31%, karstic 6.5%, fluvial 11.5%. Bogor area consists of 50 kinds of landform units, where 29.5% is on mountains, 59% on hills, dan 11.5% on plains. The study showed that on the mountains and hills there were 17% distributions of scarce groundwater potency. Local productive groundwater potency was distributed in 15% of Bogor area, small productive in 0.5%, local-moderate productive in 16.5%, wide-moderate productive in 27%, while wide-high productive in 24%. Estimate calculation of water intake from rainfall was 6.678,89 x 106 m³/year for Bogor Regency, which were distributed on the mountains about 123.656.694,79 m³/year, on the hills 126.665.275,44 m³/year, and on plains around37.983.987,77 m³/year.Keyword: Landform, Mapping Unit, Groundwater Potency