Laju Infiltrasi pada Berbagai Kemiringan dan Penggunaan Lahan di Imogiri, Bantul

ALIA HASNA, Ir. Suci Handayani, M.P.; Dr. Makruf Nurudin, S.P., M.P.

2023 | Skripsi | S1 ILMU TANAH

Penelitian ini bertujuan untuk mengetahui nilai laju infiltrasi dan hubungannya dengan karakteristik tanah pada berbagai penggunaan lahan dan kemiringan lereng di Imogiri, Kabupaten Bantul, Yogyakarta. Metode penelitian yang digunakan adalah survei lapangan, analisis data lapangan, dan analisis data laboratorium dengan pendekataan satuan lahan sebagai satuan pemetaan. Titik sampel pada penelitian ini berjumlah 35 titik yang diperoleh dengan metode penentuan titik sampling berupa metode sistematic sampling. Pengukuran laju infiltrasi dan pengambilan tanah sampel dilakukan pada kedalaman 0-20cm. Pendekatan analisis statistika yang digunakan adalah rancangan bersarang (nested design) dan analisis regresi. Karakteristik tanah yang dianalisis adalah kadar lengas awal, berat volume, berat jenis, distribusi pori, bahan organik, dan tekstur tanah. Laju infiltrasi diukur menggunakan single ring infiltrometer. Pengamatan laju infiltrasi dilakukan selama 1 menit (5 kali), 4 menit (5 kali), dan 9 menit (3 kali). Hasil penelitian menunjukkan bahwa kemiringan lereng dan penggunaan lahan yang tersarang pada kemiringan lereng berpengaruh nyata terhadap laju infiltrasi. Rerata nilai laju infiltrasi yang diperoleh pada kemiringan sangat landai di sawah 0,065 cm.jam-1, hutan 0,401 cm.jam-1, tegalan 0,261 cm.jam-1; kemiringan landai di sawah 0,073 cm.jam-1, hutan 0,495 cm.jam-1, tegalan 0,405 cm.jam-1; kemiringan agak curam di sawah 0,0565 cm.jam-1, hutan 0,5767 cm.jam-1, tegalan 0,3780 cm.jam-1; kemiringan curam di sawah 0,1680 cm.jam-1, hutan 0,533 cm.jam-1, dan tegalan 0,147 cm.jam-1.

The objective of this research aims to determine the soil infiltration rate and its corelation with soil properties in various land use and slope in Imogiri, Bantul, Yogyakarta with several approach methods. The technique of determining the sample point by systematic sampling method, obtained 34 sample point. The infiltration measurement and soil sample done at topsoil layer (0-20 cm). The statistical analysis approach of this research uses a nested design and linear regression statistical analysis. The analyses soil properties include soil moisture, bulk density, particle density, power free, organic matter, and soil texture. Infiltration rate was performed using single ring infiltrometer. Observation of infiltration was carried out of 1 minute (5 times), 4 minute (5 times), and 9 minutes (3 times). The result showed that slope level and land use variation significantly affected on soil infiltration rate. The average of infiltration in paddy dry field in flat slope was 0,065 cm.h-1, forest in flat slope was 0,401 cm.h-1, moor in flat slope was 0,261 cm.h-1; paddy dry field in rolling slope was 0,073 cm.h-1, forest in rolling slope was 0,495 cm.h-1, moor in rolling slope was 0,405 cm.h-1, paddy dry field in hilly slope was 0,0565 cm.h-1, forest in hilly slope was 0,5767 cm.h-1, moor in hilly slope was 0,3780 cm.h-1, paddy dry field in steep slope was 0,1680 cm.h-1, forest in steep slope was 0,533 cm.h-1, and moor in steep slope was 0,147 cm.h-1.

Kata Kunci : kemiringan lereng, laju infiltrasi, nested design, penggunaan lahan