PENGARUH VARIASI KEDALAMAN LUBANG RESAPAN BERBASIS BIOPORI DAN JENIS BAHAN ORGANIK TERHADAP PERMEABILITAS TANAH

Abstract

Lubang Resapan Biopori (LRB) merupakan teknologi konservasi tanah dan air yang berpotensi memengaruhi permeabilitas tanah melalui penambahan bahan organik. Penelitian ini bertujuan mengkaji pengaruh penerapan LRB, kedalaman lubang, dan jenis bahan organik terhadap permeabilitas tanah serta menentukan kombinasi perlakuan dengan permeabilitas tertinggi. Penelitian dilaksanakan di petak erosi Kebun Pendidikan Cikabayan, IPB University, menggunakan Rancangan Acak Kelompok dengan lima perlakuan dan tiga kelompok yaitu kontrol tanpa LRB, LRB berisi serasah jagung, dan LRB berisi sampah sayuran, masing-masing LRB dengan kedalaman lubang 50 cm dan 100 cm. Permeabilitas diukur dengan metode inverse auger hole, data dianalisis menggunakan analisis ragam, uji Tukey taraf 5%, serta analisis korelasi. Perlakuan berpengaruh nyata terhadap permeabilitas tanah (p=0,002). LRB berisi sampah sayuran kedalaman 50 cm dan 100 cm menghasilkan permeabilitas 2,50 cm/jam dan 2,82 cm/jam (kelas sedang), berbeda nyata dengan kontrol (1,09 cm/jam) dan LRB berisi serasah jagung kedalaman 50 cm dan 100 cm (1,11 cm/jam dan 1,16 cm/jam; kelas agak lambat). Perlakuan LRB berisi serasah jagung tidak berbeda nyata dengan kontrol. Perbedaan kedalaman LRB tidak menghasilkan perbedaan permeabilitas yang nyata. Permeabilitas tertinggi diperoleh pada LRB berisi sampah sayuran kedalaman 100 cm, namun tidak berbeda nyata dengan kedalaman 50 cm. Bobot isi, pori total, dan pori drainase tidak berbeda nyata antar perlakuan dan berkorelasi lemah dengan permeabilitas, sehingga perbedaan permeabilitas diduga berkaitan dengan keterhubungan jalur aliran air di sekitar lubang yang tidak tercermin pada sifat fisik tanah di antara lubang. Dengan demikian, sampah sayuran lebih efektif dibandingkan serasah jagung dalam meningkatkan permeabilitas tanah pada penerapan LRB.

Biopore-Based Infiltration Holes (LRB) are a soil and water conservation technology that may influence soil permeability through the addition of organic matter. This study aimed to examine the effects of LRB application, hole depth, and organic material type on soil permeability, and to determine the treatment combination with the highest permeability. The study was conducted in the erosion plots of the Cikabayan Teaching Farm, IPB University, using a Randomized Complete Block Design with five treatments and three blocks: a control without LRB, LRB filled with corn litter, and LRB filled with vegetable waste, with each LRB at hole depths of 50 cm and 100 cm. Permeability was measured using the inverse auger hole method, and the data were analyzed using analysis of variance, Tukey’s test at the 5% level, and correlation analysis. The treatments significantly affected soil permeability (p=0.002). LRB filled with vegetable waste at depths of 50 cm and 100 cm produced permeability of 2.50 cm/hour and 2.82 cm/hour (moderate class), significantly different from the control (1.09 cm/hour) and LRB filled with corn litter at depths of 50 cm and 100 cm (1.11 cm/hour and 1.16 cm/hour; moderately slow class). The corn litter LRB treatments were not significantly different from the control. Differences in LRB depth did not produce significant differences in permeability. The highest permeability was obtained with LRB filled with vegetable waste at a depth of 100 cm, but it was not significantly different from the 50 cm depth. Bulk density, total porosity, and drainage porosity did not differ significantly among treatments and were weakly correlated with permeability. Therefore, differences in permeability are presumed to be related to the connectivity of water flow paths around the holes, which is not reflected in the physical properties of the soil between the holes. Thus, vegetable waste is more effective than corn litter in increasing soil permeability in LRB application.