PENGARUH SIFAT FISIKA DAN KIMIA TANAH TERHADAP PRODUKSI KELAPA SAWIT (Elaeis guineensis Jacq. )

PUTERI SUCI APRILIANI, Ir. Eka Tarwaca Susila Putra, S.P., M. P., Ph.D

2014 | Skripsi | AGRONOMI

Penelitian bertujuan untuk 1) mengetahui pengaruh sifat fisik dan kimia tanah terhadap produktivitas kelapa sawit, serta 2) menentukan sifat fisik dan kimia tanah yang menjadi faktor pembatas produktivitas kelapa sawit. Penelitian dilaksanakan di kebun kelapa sawit milik Asian Agri Group, yaitu Bahilang (Propinsi Sumatera Utara), Aek Kuo (Propinsi Sumatera Utara), Topaz (Propinsi Riau) dan Badang (Propinsi Jambi), dengan cara mengkoleksi data sekunder di salah satu afdeling masing-masing kebun sejak tahun 2008 hingga 2012. Penelitian disusun dalam rancangan tersarang, dan faktor yang diuji adalah tingkat kesuburan tanah. Tingkat kesuburan tanah tersarang pada masing-masing lokasi penelitian sedangkan blok percobaan tersarang pada tingkat kesuburan tanah. Data sekunder yang dikoleksi mencakup sifat fisik dan kimia tanah, produktivitas kelapa sawit, rendemen minyak kelapa sawit serta kandungan asam lemak bebas dalam minyak kelapa sawit. Sedangkan data primer yang dikoleksi dari lokasi penelitian meliputi kandungan klorofil a, b, dan total, aktivitas nitrat reduktase serta kandungan senyawa prolin dalam jaringan daun kelapa sawit. Data yang diperoleh selanjutnya dianalisis varian (ANOVA) pada taraf 5% dan dilanjutkan dengan analisis korelasi serta regresi sederhana untuk menentukan pola hubungan antara sifat fisika dan kimia tanah dengan hasil analisis jaringan tanaman, produktivitas tanaman, kandungan asam lemak bebas serta rendemen minyak kelapa sawit. Hasil penelitian memberikan informasi bahwa empat kebun kelapa sawit yang menjadi obyek penelitian memiliki sifat fisika tanah yang cukup baik, khususnya dari sisi proporsi fraksi pasir, debu dan lempung sehingga hal tersebut bukan merupakan faktor pembatas bagi produktivitas kelapa sawit. Derajad kemasaman serta kandungan P dan K dalam tanah merupakan faktor pembatas utama produktivitas tanaman kelapa sawit di empat lokasi kebun yang menjadi obyek penelitian. Kandungan N, Mg dan Ca dalam tanah di empat kebun kelapa sawit yang menjadi obyek penelitian sudah cukup tinggi sehingga dosis aplikasi N, Mg dan Ca dapat dikurangi pada periode pemupukan berikutnya.

The objectives of study were 1) to determine the effects of soil physical and chemical properties to the oil palm productivity, and 2) to determine the physical and chemical properties of the soil that becomes the limiting factor of oil palm productivity. The experiment was conducted in oil palm plantations belonging to the Asian Agri Group, namely Bahilang (North Sumatra), Aek Kuo (North Sumatra), Topaz (Riau) and Badang (Jambi), by collecting secondary data in each research site since 2008 to 2012. The research was conducted in nested design, and tested factor was the level of soil fertility. Soil fertility levels were nested at each research site, while the blocks were nested at each soil fertility level. Secondary data collected were physical and chemical properties of soil, productivity of oil palm, oil extraction rate (OER) and the content of free fatty acids (FFA). While the primary data collected from research sites were the content of chlorophyll a, b, and total, nitrate reductase activity (ANR), as well as the content of proline in the leaf tissues of oil palm. Data were analyzed with Analysis of Variance (ANOVA) at 5% levels, and continued with the correlation and regression analysis to determine the pattern of the relationships between physical and chemical properties of soil with leaf tissue analysis results, oil palm productivity, and the contents of FFA as well as OER. The results showed that four oil palm plantations that became the objects of research have the optimal soil physical properties, especially from the side of the proportion of sand, dust and clay fractions, so that it was not the limiting factor of oil palm productivity. The soil pH as well as P and K contents in the soil were the main limiting factor of oil palm productivity in the research sites. The contents of N, Mg and Ca in the soils of all research sites were already high so that the dosage application of N, Mg and Ca were reduced in the future fertilization program.

Kata Kunci : kelapa sawit, produktivitas, sifat fisika dan kimia tanah