KARAKTERISTIK KESUBURAN FISIK TANAH PERMUKAAN DI LONGSORLAHAN TIDAK AKTIF DAS BOMPON KABUPATEN MAGELANG, JAWA TENGAH

ZULFA SIRLINA ROFI ISTIQOMAH, Prof. Dr. rer.nat.Junun Sartohadi, M.Sc

2018 | Skripsi | S1 GEOGRAFI LINGKUNGAN

Kajian mengenai karakteristik fisik tanah permukaan dilakukan pada longsorlahan tidak aktif di DAS Bompon, Kabupaten Magelang, Jawa Tengah. Penelitian memiliki tujuan untuk (1)mengkaji morfologi longsor tidak aktif; (2)menemukenali karakteristik fisik tanah permukaan longsor tidak aktif; (3)menganalisis kesuburan fisik setiap bentuklahan longsor tidak aktif di Dusun Bompon, Desa Wonogiri. Pendekatan geomorfologi dilakukan guna mengetahui morfologi, material, dan proses yang masih berlangsung. Tahapan dilakukan melalui survey lapangan kondisi morfologi longsor, analisis profil tanah, dan analisis laboratorium. Hasil penelitian menunjukkan longsor tidak aktif daerah penelitian memiliki sudut lereng 1,35o-43,5o, ketinggian 415-485 mdpl, arah hadap longsor ke Tenggara. Longsor tidak aktif dapat dibagi kedalam 5 morfologi longsor yaitu mahkota, gawir, kepala longsor, badan longsor, dan kaki longsor. Karakteristik fisik tanah uji laboratorium meliputi parameter tekstur, permeabilitas, berat jenis, berat volume, porositas, dan nilai-nilai konsistensi. Tingkat kesuburan tanah diperoleh dari klasifikasi kedalaman efektif tanah, tekstur tanah, dan permeabilitas. Longsor tidak aktif daerah penelitian terbagi dalam dua klasifikasi kesuburan yaitu kesuburan fisik rendah dan sedang.

The research of physical characteristics of surface soil was carried out on not active landslides in the Bompon watershed, Magelang District, Central Java. The research aims to (1) determine the not active landslide morphology; (2) identify physical characteristics of not active landslide surface soil; (3) analyze the physical fertility of landform of not active landslide in Bompon Hamlet, Wonogiri Village. The geomorphological approach is carried out to determine the morphology, material, and processes that still develop. The steps were carried out through field surveys of landslide morphological conditions, soil profile analysis, and laboratory analysis. The results show that the not active landslide in study area had a slope of 1.35o-43.5o, an altitude of 415-485 meters above sea level, direction towards landslide to the Southeast. Not active landslides can be divided into 5 landslide morphologies namely crown, scarp, landslide head, main body, and toe. Physical characteristics of laboratory test soil include texture, permeability, specific gravity, volume weight, porosity, and consistency values. The level of soil fertility is obtained from the classification of soil depth, soil texture, and permeability. Not active landslides Bompon Village is divided into two categories of fertility, namely low and moderate physical fertility.

Kata Kunci : karakteristik kesuburan fisik, kesuburan tanah, longsorlahan tidak aktif, morfologi, tanah