Indeks Kualitas Tanah pada Lahan Pertanian dengan Sistem Pola Tanam Monokultur dan Polikultur di Ngablak, Magelang

Novita Dewi Maharani, Prof. Dr. Ir. Sri Nuryani Hidayah Utami, M.P., M.Sc.; Imas Masithoh Devangsari, S.P., M.Sc., Ph.D.

2026 | Skripsi | ILMU TANAH

Penelitian ini bertujuan menganalisis perbedaan Indeks Kualitas Tanah (IKT) pada lahan monokultur, polikultur, dan kontrol (semak belukar) di tanah Andisol Dusun Dukuh, Desa Sumberejo, Kecamatan Ngablak, Kabupaten Magelang. Sampel tanah diambil pada 5 titik sampel tanah dengan dua kedalaman (0–20 cm dan 20–40 cm) di masing-masing lahan. Parameter yang dianalisis meliputi sifat fisika (berat jenis, berat volume, porositas), kimia (pH H?O, pH NaF, C-Organik, KPK, N-Total, P-Tersedia, K-Tersedia), dan biologi (respirasi tanah). IKT dihitung menggunakan konsep SMAF berbasis Minimum Data Set (MDS) dan dianalisis dengan ANOVA, DMRT 5%, korelasi Pearson, serta regresi Stepwise. Hasil penelitian menunjukkan nilai IKT tertinggi pada lahan polikultur (30,91; harkat sedang), diikuti monokultur (27,67; harkat sedang), dan kontrol (25,92; harkat rendah). Parameter kimia tanah, terutama P-Tersedia dan KPK, serta kelimpahan cacing tanah secara konsisten paling tinggi pada lahan polikultur. Analisis regresi Stepwise mengidentifikasi pH NaF sebagai parameter paling dominan (r = 0,898) dengan kontribusi bersama pH H?O, P-Tersedia, N-Total, dan KPK sebesar 91,9% (R² = 0,919) terhadap IKT. Sistem tanam polikultur terbukti paling efektif meningkatkan kualitas tanah Andisol melalui diversifikasi bahan organik dan perbaikan sifat kimia tanah.

 

This study aimed to analyze differences in Soil Quality Index (SQI) under monoculture, polyculture, and control (shrubland) land-use systems on Andisol soils in Dukuh Hamlet, Sumberejo Village, Ngablak District, Magelang Regency. Soil samples were collected from five sampling points at two depths (0–20 cm and 20–40 cm) in each land-use system. Analyzed parameters included physical properties (particle density, bulk density, porosity), chemical properties (pH H?O, NaF-pH, organic-C, CEC, total-N, available-P, available-K), and biological properties (soil respiration). SQI was calculated using the SMAF concept based on a Minimum Data Set (MDS) and analyzed using ANOVA, DMRT 5%, Pearson correlation, and Stepwise regression. Results showed that SQI was highest in polyculture (30,91; medium), followed by monoculture (27,67; medium), and control (25,92; low). Soil chemical parameters, particularly available-P and CEC, as well as earthworm abundance, were consistently highest in polyculture. Stepwise regression identified NaF-pH as the most dominant parameter (r = 0.898), with NaF-pH, pH H?O, available-P, total-N, and CEC collectively explaining 91.9% (R² = 0.919) of SQI variation. Polyculture proved most effective in improving Andisol soil quality through diversified organic matter inputs and improved soil chemical properties.

Kata Kunci : Andisol, indeks kualitas tanah, monokultur, pH NaF, polikultur, SMAF