Key technical points for restoring flood-damaged farmland to help post-disaster production recovery

I. Adopt engineering measures for restoration

Sloping farmland in mountainous and hilly areas, as well as farmland on river valley terraces and on both sides of rivers, has been severely damaged by floods and must be restored through engineering measures.

1. Repair terraces. Repair the terrace walls, dams and field ridges damaged by floods, remove silt, sand and stones, and at the same time build stone embankments to consolidate gully and valley protection works.

2. Level the land. For farmland severely scoured and gullied by floods, fill in the gullies, level the land, and keep the farmland surface level.

3. Restore cultivation with borrowed soil. Where flood scouring has caused severe loss of the soil layer, restore cultivation by adding borrowed soil and padding with soil to increase the thickness of the soil layer, bringing the soil layer to about 50 cm.

4. Drain standing water. For farmland soaked by floods, drain the standing water as soon as possible by digging drainage ditches or pumping water with pumps, to prevent long-term flooding and soaking.

II. Adopt agronomic measures to build fertility

After farmland is scoured, eroded and soaked by floods, the soil structure deteriorates, the capacity to retain water and fertilizer decreases, soil nutrients are lost, and soil fertility declines. The following agronomic measures can be adopted to build fertility and improve the soil.

1. Break up soil crusting. After farmland is soaked by floods, sediment is easily deposited, and the soil easily crusts after drying, which is unfavorable for crop growth. Carry out field intertillage and hoeing in a timely manner, which helps the soil release moisture, improves the rhizosphere environment, breaks up plow-layer crusting, and prevents damage to roots and seedlings.

2. Replenish soil nutrients. In farmland washed and flooded by water, soil nutrients are severely lost, so quick-acting fertilizers should be applied in a timely manner to replenish nutrients and promote crop recovery growth.

3. Increase application of organic fertilizer. After farmland is flood-damaged, the texture of the plow layer is prone to becoming sandy or clayey, and the organic matter content decreases. Therefore, vigorously increase the application of organic fertilizer, applying more than 3-5 cubic meters of high-quality farmyard manure per mu, and where conditions permit, apply commercial organic fertilizer, so as to restore soil fertility.

III. Adopt biological measures for improvement

On severely flood-damaged farmland, green manure crops such as the leguminous alfalfa, sweet clover and sesbania can be planted, then plowed under and returned to the field to build fertility and improve the soil.

Seed Management Station of Hebei Province, Zhang Xutong

Green Food Office of Hebei Province, Dong Bozhao

Crop Introduction and Breeding Center of Hebei Province, Zhang Yaozong