THE EFFECT OF LONG-TERM SOIL TREATMENT AND N FERTILIZATION ON ORGANIC CARBON CONTENT, SOIL NITROGEN AND N ABSORPTION AND PRODUCTION IN CORN CROPING IN ULTISOL SOIL, YEAR 3

Abstract

Ultisol is a type of soil in Indonesia with a wide distribution. Ultisol is soil that has a low fertility level so it needs improvement efforts so that it can be used optimally. The aim of the research was to determine the effect of long-term tillage, N fertilization, and the interaction between long-term tillage and N fertilization on soil organic C levels, total soil N, N uptake, and corn crop production in Ultisol. The research was carried out on 12 September 2021 – 30 January 2022 at the Polinela Experimental Garden. This research uses RAK with 2 factors, namely nitrogen fertilization (N0 = no fertilization, N2 = 200 kg N ha-1 fertilization), tillage (T1 = intensive tillage, T2 = minimum tillage, T3 = no tillage). Data from research on soil properties, initial and final soil analyzes were carried out to determine the soil total N content, soil organic C, C/N, and soil pH. Soil data analysis was carried out qualitatively using assessment criteria for soil analysis. Plant sample data in the form of (dry, wet weight production and plant N uptake) was tested using an ara and continued with a 5% LSD (least significance different) test. Without tillage and without N fertilization can increase soil organic C and total soil N. The highest corn stover N uptake was in the minimum tillage treatment. N fertilization is not able to increase organic C content, but can increase total soil N. N fertilization can increase the production of total dry weight and total wet weight of plants as well as total N transport. There was no interaction between the effect of N fertilization and tillage on N uptake and corn production.