PENERAPAN MODEL HORTONUNTUK KUANTIFIKASI INFILTRASI TEGAKAN KARET DI DAS MALUKA PROVINSI KALIMANTAN SELATAN

Abstract

DAS Maluka seluas 89.506,19 Ha terdapat sub DAS Banyu Irang dan sub DAS Bati Bati serta secara administrasi tersebar di 3 kabupaten/kota yaitu Kabupaten Tanah Laut, Kabupaten Banjar dan Kota Banjarbaru Provinsi Kalimantan Selatan. DAS Maluka didominasi kekritisan lahan agak kritis 63%, kelerengan lereng didominasi tingkat kelerengan 0-8% 79,88%, tutupan lahan didominasi tutupan lahan perkebunan 17,91%, Kerusakan lingkungan di DAS Maluka telah menjadi keprihatinan banyak pihak, hal ini ditandai dengan meningkatnya bencana alam yang dirasakan, seperti bencana banjir, tanah longsor dan kekeringan yang semakin meningkat. Rendahnya kapasitas infiltrasi sebaliknya tingginya Surface run off  penyebab utama terjadinya bencana alam yang terkait dengan tata air. Penelitian ini menggunakan model Horton yang bertujuan mengetahui infiltrasi terhadap berbagai kelas umur tegakan karet (Hevea brasiliensis). Metode penelitian menggunakan doubel ring infiltrometer pada kelas umur 4 tahun, 8 tahun dan 12 tahun. Hasil penelitian diperoleh bahwa:1) Kapasitas infiltrasi 96,906 mm/jam, 103,981 mm/jam dan 104,651 mm/jam; 2) volume infiltrasi sebesar 93,432 m3,  95,945 m3, 591 m3; 3) semakin tinggi kelas umur tegakan karet semakin tinggi laju, kapasitas dan volume infitrasi. Kata kunci : infiltrasi, surface run off , vegetasi tegakan karet.  The Maluka watershed covers an area of 89,506.19 Ha, there are the Banyu Irang sub-watershed and the Bati Bati sub-watershed and are administratively spread across 3 regencies / cities, namely Tanah Laut Regency, Banjar Regency and Banjarbaru City South Kalimantan Province. The Maluka watershed is dominated by criticality of the rather critical land 63%, the slope is dominated by the slope level of 0-8% 79.88%, land cover is dominated by plantation land cover 17.91%, environmental damage in the Maluka watershed has become a concern of many parties, this is indicated by increasing perceived natural disasters, such as floods, landslides and increasing drought. The low infiltration capacity, on the other hand, is the high Surface run off, the main cause of natural disasters related to water management. This study uses the Horton model that aims to determine infiltration of various age groups of rubber stands (Hevea brasiliensis). The research method uses a doubel ring infiltrometer in the age class of 4 years, 8 years and 12 years. The results showed that: 1) Infiltration capacity of 96,906 mm / hour, 103,981 mm / hour and 104,651 mm/ hour; 2) infiltration volume of 93,432 m3, 95,945 m3, 591 m3; 3) the higher the age of rubber stand age, the higher the rate, capacity and volume of inflation. Keywords: infiltration, surface run off and rubber stand vegetation.