Dampak Jangka Pendek Pengelolaan Jerami Padi terhadap Karbon Organik dan Rasio CN Tanah

Abstract

Siklus tanam padi tahunan menghasilkan 6,73 ton jerami kering per hektar. Jerami memiliki potensi unsur hara yang bermanfaat bagi tanaman. Untuk mengurangi limbah jerami dan meningkatkan kesuburan tanah, petani sering membakar jerami padi atau membenamkannya ke dalam tanah. Karena jerami padi sulit terdekomposisi, diperlukan tambahan dekomposer seperti bakteri. Penelitian ini bertujuan untuk mengetahui dampak jangka pendek dari pengelolaan jerami padi terhadap C-organik dan C/N rasio pada tanah. Rancangan percobaan yang digunakan yaitu Nested Design. Tiga perlakuan dilakukan: pembakaran, pembenaman jerami tanpa EM4, dan pembenaman jerami dengan EM4. Analisis laboratorium dilakukan pada parameter C-organik dan C/N rasio. Perbedaan parameter tanah yang diamati antara sebelum dan sesudah perlakuan pengelolaan jerami menggunakan uji Wilcoxon Signed Rank Test. Hasil analisa menunjukkan C-organik sesudah perlakuan mengalami peningkatan, pada perlakuan pembakaran meningkat sebesar 29,7%, pada perlakuan pembenaman jerami meningkat sebesar 10,9%, dan pada perlakuan pembenaman jerami dengan EM4 meningkat sebesar 10,2%. Meningkatnya C-organik setelah perlakuan pengelolaan jerami disebabkan karena adanya mineralisasi bahan organik tanah. Mineralisasi bahan organik tanah ditunjukkan dengan nilai rata-rata C/N di bawah 20, walaupun nilai C/N rasio pada perlakuan setelah pembakaran meningkat sebesar 56% dan pada perlakuan pembenaman jerami dengan EM4 meningkat sebesar 0,35%, dimana nilai rata-rata C/N rasio yang didapat dari semua perlakuan berkisar antara 9,1 – 16,8. Dalam jangka pendek, ketiga perlakuan jerami dapat meningkatkan karbon organik dan menghasilkan nilai C/N rasio di bawah 20.

The annual rice planting cycle produced 6.73 tons of dry straw per hectare. Rice straw had beneficial nutrients for plants, but to reduce waste and enhance soil fertility, farmers often burned or buried it. Because straw was hard to decompose, additional decomposers like bacteria were needed. This study aimed to investigate the short-term impact of rice straw management on soil organic carbon (C-organic) and the C/N ratio. The experimental design used was Nested Design. The study involved three straw management treatments: burning, straw incorporation without EM4 addition, and straw incorporation with EM4 addition. Laboratory analysis was conducted on the C-organic and C/N ratio parameters. Differences in soil parameters observed before and after straw management treatments were analyzed using the Wilcoxon Signed Rank Test. The analysis results showed an increase in C-organic after treatment: 29.7% for burning, 10.9% for straw incorporation, and 10.2% for straw incorporation with EM4. The increase in C-organic after straw management treatments is due to the mineralization of soil organic matter. This mineralization is indicated by average C/N values below 20, although the C/N ratio after burning increased by 56% and after straw incorporation with EM4 increased by 0.35%. The average C/N ratios from all treatments ranged from 9.1 to 16.8. In the short term, all three straw treatments can increase organic carbon and result in C/N ratios below 20.