Pemodelan Linear dan Pendugaan Pengaruh Kompetisi Antartanaman dalam Percobaan Lapangan
Abstract
Model spasial dua dimensi digunakan untuk menduga pengaruh kompetisi antartanaman yang saling berdekatan. Data yang digunakan adalah data hasil percobaan pengaruh pemupukan terhadap produksi berat buah tandan segar kelapa sawit per pohon selama enam bulan. Model yang melibatkan pengaruh kompetisi antartanaman kemudian dibandingkan dengan model tanpa pengaruh kompetisi. Nilai MSE digunakan sebagai dasar perbandingan kedua model. Hasil penelitian menunjukkan tidak terdapat pengaruh perlakuan yang signifikan di dalam kedua model. Oleh karena itu tidak dilakukan perhitungan lebih lanjut untuk membandingkan pengaruh perlakuan. Hasil penelitian juga menunjukkan bahwa model biasa (model Anova) menghasilkan nilai MSE yang lebih kecil dari model dengan pengaruh kompetisi.Jarak tanam yang lebar (9m) pada perkebunan kelapa sawit telah secara efektif mengurangi pengaruh kompetisi antartanaman.
Two-dimensional spatial models are used to predict the influence of inter-plant competition. The data are obtained from experimental trial to investigate the effect of fertilization on the production of oil palm fresh fruit bunches per tree for the period of six months. Model involving the influence of inter-plant competition are then compared with models without the influence of competition. The comparison was based on the MSE of the models. Both model showed no significance of the treatment effects, hence no further calculation was carried out to compare the treatment effects. The study also showed that the ordinary model (Anova model) resulted in a smaller MSE than the competition model. The 9m spacing between trees seems to have effectively reduced the competition effect between the neighboring trees.
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