Effects of agricultural management on the chemical properties of cultivated soils in the middle and lower reaches of the Ishikari River, Hokkaido

Abstract

In the middle and lower reaches of the Ishikari River, flatlands and plateaus have changed from wetlands to agricultural land, and mountainous areas have changed from natural forests to artificial forests and secondary forests. In addition, the management of agricultural land changed due to changes in social conditions. As a result, the basin soil is expected to undergo major changes, leading to changes in water quality and agricultural productivity in rivers and coastal areas. Therefore, in this study, we conducted a survey to understand the current state of the soil in the basin. It was considered necessary to pay attention to soil carbon content when considering environmental conservation such as water quality, and to soil chemistry when considering agricultural productivity.