We study methods for conserving and improving agricultural soils that are sustainable and capable of providing rich natural benefits. In particular, we identify technical measures through meticulous field measurements from the perspectives of crop growth and quality, soil physical properties, and material and water cycles. To support this work, we apply theoretical and experimental findings from related fundamental research.

1. Low-Input, Sustainable Rice Cultivation in Northern Regions
   Sustainable agricultural production is an urgent issue for the future of human society. We investigate nutrient dynamics in paddy soils under low-input rice cultivation practices, including methods using no fertilizers, no pesticides, and repeated intertillage-based weed control.

2. Crop Production and Soil Material Dynamics under Regenerative Agriculture
   Although conventional agriculture has improved productivity, it has also contributed to environmental burdens. In recent years, regenerative agricultural practices—such as no-till farming and the use of cover crops—have received growing attention. We examine soil material dynamics under regenerative agriculture.

3. Drainage Improvement in Upland Fields
   In upland fields, soil physical properties, including water-holding capacity and drainage, strongly influence crop growth. In the cool and humid climate of Hokkaido, enhancing soil drainage is particularly important. We explore ideal forms of upland soils that remain functional regardless of climate variability.

4. Soil Erosion Control and Chemical Fertilizers
   We analyze the effects of chemical fertilizers on soil structure and consider strategies for mitigating soil erosion.

5. Field Improvement and Soil Management for Wine Grape Cultivation
   In recent years, wine grape cultivation has expanded across Hokkaido. We study appropriate drainage improvement techniques and soil physicochemical properties that promote root system development in major vineyards throughout the region.