Hubungan Hantaran Hidrolik Tanah dengan Sifat Fisik Tanah Akibat Olah Tanah Konservasi serta Pengaruhnya terhadap Aliran Permukaan dan Erosi

Abstract

Aliran permukaan dan erosi merupakan penyebab penurunan kualitas sifat fisik tanah di daerah tropika basah seperti di Indonesia. Untuk mengurangi besarnya aliran permukaan dapat dilakukan dengan peningkatan kemampuan peresapan tanah (hantaran hidrolik). Berbagai teknik konservasi tanah dan air dapat meningkatkan hantaran hidrolik tanah melalui perbaikan sifat-sifat fisik tanah, yang selanjutnya diharpkan dapat mengurangi aliran permukaan dan erosi. Oleh karena itu perlu dilakukan penelitian tentang pengaruh teknik konservasi tanah dan air terhadap hantaran hidrolik tanah. Serangkaian penelitian dilakukan di lapangan untuk mengamati hantaran hidrolik dan sifat-sifat fisik yang mempengaruhinya serta pengaruhnya terhadap aliran permukaan dan erosi. Penelitian dilakukan di Kebun Pendidikan Cikabayan, IPB Dramaga, dengan perlakuan Kontrol (P1), Slot Till (P2), Slot Till + teras gulud + saluran (P3), Slot Till + teras gulud + saluran + mulsa organik (P4), dan Slot Till + teras gulud + saluran + mulsa organik + LRB (P5) yang disusun dalam rancangan acak lengkap (RAL). ). Hasil penelitian menunjukkan bahwa hantaran hidrolik pada perlakuan Slot Till + teras gulud + saluran + mulsa organik (P4) paling besar (3.05 cm/jam), diikuti oleh hantaran hidrolik pada perlakuan Slot Till + teras gulud + saluran + mulsa organik + LRB (P5; 2.68 cm/jam), P3 (2.32 cm/jam), P2 (1.71 cm/jam), dan P1 (0.85 cm/jam). Hantaran hidrolik tanah dipengaruhi oleh bobot isi, stabilitas agregat, dan ruang pori drainase. Peningkatan hantaran hidrolik tanah akibat teknik konservasi tanah dan air di atas dapat menurunkan aliran permukaan dan erosi.

Surface runoff and erosion are causes of a decrease in the quality of soil physical properties in wet tropical areas such as Indonesia. To reduce the amount of surface runoff, it can be done by increasing the soil's hydraulic conductivity. Various soil and water conservation techniques can increase the hydraulic conductivity of the soil by improving the physical properties of the soil, which in turn is expected to reduce surface runoff and erosion. Therefore, it is necessary to conduct research on the effect of soil and water conservation techniques on soil hydraulic conductivity. A series of studies were carried out to observe hydraulic conductivity and the physical properties that influence it as well as their effect on surface runoff and erosion. The research was conducted at the Cikabayan Field Stasion, IPB Dramaga, with Control (P1), Slot Till (P2), Slot Till + bund terrace + channel (P3), Slot Till + bund terrace + channel + organic mulch (P4), and Slot treatments. Slot Till + bund terrace + channel + organic mulch + LRB (P5) arranged in a completely randomized design (RAL). The results showed that the hydraulic conductivity in the Slot Till + bund terrace + channel + organic mulch (P4) treatment was the greatest (3.05 cm/hour), followed by the hydraulic conductivity in the Slot Till + bund terrace + channel + organic mulch + LRB (P5; 2.68 cm/hour), P3 (2.32 cm/hour), P2 (1.71 cm/hour), and P1 (0.85 cm/hour). Soil hydraulic conductivity is influenced soil bulk density, soil aggregate stability, and drainage pore space. The increased of soil hydraulic conductivity due to soil and water conservation techniques can reduce surface runoff and erosion