长期灌溉不当使土壤盐碱化，大片农田逐渐变成碱荒地。
Improper long-term irrigation caused the soil to become saline-alkaline, and large areas of farmland gradually turned into alkaline wasteland.
Improper long-term irrigation caused the soil to become saline-alkaline, and large areas of farmland gradually turned into alkaline wasteland.