Soil and water conservation effects of different tillage measures on phaeozems sloping farmland in northeast China

Conventional tillage is still widely practiced in phaeozems sloping farmland, which leads to serious soil erosion. Adopting effective farming methods is crucial for mitigating soil erosion. To prevent and control soil and water loss in phaeozems sloping farmland, field experiments were conducted in 2022 using three tillage methods and their combination modes: subsoiling tillage (SF), ridge tillage and pitting field (RF), ridge tillage and pitting field + subsoiling tillage (RF-S), contour tillage (TP), contour tillage + ridge tillage and pitting field (TP-R), and contour tillage + subsoiling tillage (TP-S). The study aimed to assess the impact these different tillage methods on soil and water conservation. The results showed that the contour tillage + ridge field treatment significantly reduced surface runoff and soil loss (p < 0.05), with no observed nutrient loss. Compared with other treatments, this method significantly reduced runoff, erosion, and nutrient loss. In contrast, the contour tillage + subsoiling tillage treatment significantly decreased the soil three-phase R-value, improved the soil texture, and exhibited higher yield, harvest index, and water use efficiency (WUE) compared to alternative treatments. Overall, the comprehensive findings indicate that contour tillage + subsoiling tillage can reduce soil erosion, enhance soil quality, and improve the WUE, all while maintaining high production capacity. Furthermore, the results of this study provide a theoretical basis for conserving soil and water resources, improving soil fertility, and increasing farmland yield in the phaeozems area of northeast China.