From soil to bowl: Unearthing the hidden connections between rice cultivation and daily life in Japan

<p>The Courses of Study for Elementary Schools in the Home Economics section emphasizes that “students should understand that rice is a staple food integral to the Japanese diet.” Furthermore, the 5th grade social studies section asserts the importance of “rice cultivation, which plays a crucial role in securing the nation’s staple food.” However, the necessity of soil for rice cultivation is not explicitly mentioned in either the home economics and social studies sections or the 4th grade science section that discusses soil particles. This study aimed to visualize the relationship among rice grains, rice plants, rice fields, water, and soil. It quantified the number of grains of polished rice and rice plants required for one bowl of curry rice (150 g cooked rice) and the area and mass of topsoil required to produce it. According to the calculations, approximately 3,571 grains of polished rice per bowl of curry rice are produced by 2.25, 2.22, and 3.85 rice plants of the composted, chemical fertilized, and no-fertilized areas, respectively. These rice plants require 30.6 kg, 30.6 kg, and 50.8 kg of moist soil (with 16.5, 15.9, and 26.3 kg moisture content) to grow. The water required to produce one bowl of curry rice includes the water used to cook the rice grains and the water in the soil of rice fields. However, only the former is mentioned in elementary school home economics classes. The water retention and permeability functions of soils, particularly those generated under forests, are crucial for maintaining moist soil. As a result, the role of forests as a water source is included in 5th grade social studies. Incorporating soil studies into the school curriculum can help students understand the connection between agriculture, their daily lives, and society. This approach can provide students with developmental and exploratory learning experiences that are relevant to home economics, social studies, and science.</p>