Asian Journal of Soil Science and Plant Nutrition

Flooding can damage agricultural land because it can carry and deposit mud, wood waste, gravel, rocks, and sand, causing damage and loss of topsoil. The purpose of this study was to determine the post-flood soil nutrient content in rice fields in Lempake Village, Samarinda City. This research was conducted from June to November 2024 in the rice fields of Lempake Village, and soil analysis was conducted at the Soil Science Laboratory, Faculty of Agriculture, Mulawarman University. Soil samples were collected in the field using simple random sampling at 13 points before and 13 points after the flood. Soil chemical properties were analyzed using the disturbed soil composite method, including soil pH, total N and N-available analysis, total K analysis, and Cu-availability. Data analysis was conducted using a comparative descriptive method by comparing the results of soil sample analysis with the soil chemical analysis data assessment criteria set out in the soil analysis results assessment criteria of the Ministry of Agriculture of the Republic of Indonesia. The results of the study showed that flooding in rice fields can cause a decrease in soil pH (from 3.02 to 2.92), NO₃^- content (from 4.57 ppm to 1.52 ppm), NH₄⁺ content (from 2.27 ppm to 1.09 ppm), available K content (from 59.17 ppm to 20.83 ppm) and Cu content (from 7.96 ppm to 6.66 ppm).