Evaluasi Metode Penetapan Kadar Asam Humat dalam Pembenah Tanah: Perbandingan Metode NSM, Juknis, dan Metode Internal ICBB

Abstract

Penetapan kadar asam humat (HA) yang andal dan efisien sangat penting untuk penjaminan mutu produk pembenah tanah. Akan tetapi, ketersediaan metodenya masih terbatas dan ditemui kendala terhadap acuan rutin, sementara permintaan jumlah analisis HA di Laboratorium Indonesian Center for Biodiversity and Biotechnology (ICBB) terus meningkat. Sebanyak empat metode penetapan kadar HA, yaitu new standardized method (NSM) (gravimetri), petunjuk teknis (juknis) (spektrofotometri), serta metode internal ICBB (modifikasi gravimetri dan spektrofotometri) dievaluasi untuk menilai kelayakan setiap metode. Evaluasi didasarkan pada analisis statistik dan kinerja presisinya terhadap dua jenis sampel pembenah tanah, yaitu pupuk organik padat (POP) dan senyawa humat padat (SHP). Hasil penelitian menunjukkan bahwa metode spektrofotometri, khususnya metode internal ICBB berpotensi diterapkan sebagai metode rutin penetapan kadar HA. Metode tersebut memberikan presisi yang lebih baik dibandingkan dengan metode gravimetri serta menghasilkan nilai yang sebanding dengan metode NSM pada matriks POP. Temuan ini mendukung peningkatan efisiensi dan keandalan analisis HA di laboratorium.

Determining reliable and efficient humic acid (HA) levels is really important for ensuring the quality of soil conditioner products. However, the available methods are still limited, and there are issues with routine references, while the demand for HA analyses at the Indonesian Center for Biodiversity and Biotechnology (ICBB) Laboratory keeps increasing. Four methods for determining HA levels, that is new standardized method (NSM) (gravimetric), technical guidelines (juknis) (spectrophotometry), and ICBB internal methods (modified gravimetric and spectrophotometric) were evaluated to see how feasible each method is. The evaluation was based on statistical analysis and performance precision on two types of soil conditioner samples, namely solid organic fertilizer (POP) and solid humate compound (SHP). The research results show that the spectrophotometry method, especially the ICBB internal method, has the potential to be applied as a routine method for determining HA levels. This method offers better precision compared to the gravimetric method and produces values comparable to the NSM method on POP matrices. These findings support increased efficiency and reliability of HA analysis in the lab.