Evaluasi Hara Mikro Esensial (Fe, Mn, Cu, dan Zn) dan Logam Berat Beracun (Pb dan Cd) pada Tanah di Kabupaten Brebes, Jawa Tengah

Abstract

Praktik pertanian intensif yang beragam dengan penggunaan pupuk dan pestisida melebihi dosis pada wilayah utara dan selatan di Kabupaten Brebes dapat mengakibatkan disproporsi hara tanah seperti hara mikro esensial Fe, Mn, Cu, dan Zn serta akumulasi logam berat beracun Pb dan Cd yang berpotensi merugikan kesehatan tanaman, lingkungan, hingga manusia. Penelitian ini bertujuan menganalisis kondisi tanah melalui evaluasi hara mikro esensial seperti Fe, Mn, Cu, dan Zn serta logam berat beracun seperti Pb dan Cd pada tanah wilayah utara dan selatan di 39 lokasi pengambilan sampel tanah dengan penggunaan lahan pertanian dan hutan di Kabupaten Brebes, Jawa Tengah. Metode penelitian dilakukan melalui pengambilan dan persiapan sampel tanah, analisis sampel tanah di laboratorium, penilaian bioavailabilitas logam berat, dan analisis data. Keseluruhan hara mikro esensial yaitu Fe, Mn, Cu, dan Zn pada wilayah utara dan selatan memiliki kriteria cukup, namun terdapat 2 lokasi mengalami defisiensi Zn. Hara mikro esensial tanah di wilayah utara relatif lebih rendah dibandingkan dengan wilayah selatan. Hara mikro esensial memiliki korelasi dengan pH H2O, KTK, C-organik, N-total, P2O5 HCl 25%, Ca-dd, dan Na-dd. Kadar Pb dan Cd total dan Pb serta Cd tersedia tanah baik di wilayah utara maupun selatan termasuk dalam kategori normal. Kadar Pb dan Cd total tanah di wilayah utara relatif lebih rendah dibandingkan dengan wilayah selatan. Sementara itu, Pb-tersedia di tanah wilayah utara cenderung lebih tinggi dibandingkan di wilayah selatan, sedangkan Cd-tersedia di wilayah utara relatif lebih rendah daripada wilayah selatan. Logam berat beracun Pb dan Cd berkorelasi dengan N-total, KTK, dan Mg-dd. Bioavailabilitas Pb dan Cd di wilayah utara cenderung lebih tinggi daripada di wilayah selatan. Bioavailabilitas Cd lebih tinggi dibandingkan dengan Pb. Semakin tinggi bioavailabilitas logam berat maka semakin besar peluang terserapnya logam berat pada tanaman sehingga menyebabkan logam akan terakumulasi pada bagian-bagian tanaman.

Intensive agricultural practices that vary with the use of fertilizers and pesticides exceeding doses in the northern and southern regions of Brebes Regency can result in soil nutrient disproportions, such as essential micronutrients Fe, Mn, Cu, and Zn, and the accumulation of toxic heavy metals Pb and Cd, which have the potential to harm plants, the environment, and human health. This study aims to analyze soil conditions through the evaluation of essential micronutrients, such as Fe, Mn, Cu, and Zn, and toxic heavy metals, such as Pb and Cd, in northern and southern soils in 39 soil sampling locations with agricultural and forest land uses in Brebes Regency, Central Java. The research was conducted through the collection and preparation of soil samples, analysis of soil samples in the laboratory, assessment of heavy metal bioavailability, and data analysis. The overall essential micronutrients of Fe, Mn, Cu, and Zn in the north and south have sufficient criteria, but the two locations experience Zn deficiency. Essential soil micronutrients in the northern region were lower than those in the southern region. Essential micronutrients were correlated with pH H2O, CEC, organic C, total N, P2O5 HCl 25%, exchangeable Ca and Na. The total Pb and Cd and soil available Pb and Cd in both the northern and southern regions were in the normal category. The total Pb and Cd in the northern region were lower than those in the southern region. Meanwhile, available Pb in the soil of the northern region tended to be higher than that in the southern region, while available Cd in the northern region was relatively lower than that in the southern region. Toxic heavy metals Pb and Cd were correlated with the total N, CEC, and exchangeable Mg. The bioavailability of Pb and Cd tended to be higher in the northern region than in the southern region. The bioavailability of Cd is higher than that of Pb. The higher the bioavailability of heavy metals, the greater the chance of heavy metal absorption in plants, causing metals to accumulate in the plant parts.