Long-Term Conservation Agriculture Improves Soil Quality in Sloped Farmland Planting Systems

• Published in: Plants (Basel) 2024-12, Vol.13 (23), p.3420
• Main Authors: Li, Hongying, Tang, Jun, Wang, Jing, Qiao, Jun, Zhu, Ningyuan
• Format: Article
• Language: English
• Subjects: Agricultural conservation; Agricultural land; Agricultural practices; Agricultural production; Agriculture; Alfalfa; Beans; Canyons; Citrus; Citrus fruits; Conservation; Conservation practices; Contours; crop field; Crop fields; discriminant analysis; Field tests; Fruits; Hedgerows; Influence; Intercropping; Legumes; Mimosaceae; Nonpoint source pollution; orchard; Orchards; Peanuts; Physical properties; Planting; Position measurement; Rain; Rotation; Runoff; Soil conservation; Soil degradation; Soil erosion; Soil improvement; Soil properties; Soil quality; soil quality index; Sustainable agriculture; Watersheds; Wheat
• ISSN: 2223-7747; 2223-7747
• DOI: 10.3390/plants13233420

Conservation agriculture practices (CAs) are important under the increasingly serious soil quality degradation of sloping farmlands worldwide. However, little is known about how the long-term application of CAs influences soil quality at different slope positions. We conducted field experiments for a watershed sloping farmland's mainstream planting systems in the Three Gorges Reservoir area of China. Orchard plots were treated with a conventional citrus planting pattern (C-CK), citrus intercropped with white clover (WC), citrus orchard soil mulched with straw (SM) and citrus intercropped with contour hedgerows (HF). Crop field plots were treated with a conventional wheat-peanut rotation (W-CK), a wheat-peanut rotation intercropped with contour hedgerows (TS), a wheat-peanut rotation intercropped with alfalfa contour hedgerows (AF) and a ryegrass-sesame rotation (RS). We collected soil samples from the plots at the upper, middle and lower slope positions and measured their soil properties after a nine-year experiment. We found that (1) CAs improved the soil properties at the three slope positions; (2) the effect of the CAs on the soil properties was more significant than that on the slope position; and (3) the soil quality index at the upper, middle and lower slope positions increased by 29.9%, 45.8% and 33.3%, respectively, for WC; 48.7%, 39.5% and 27.1%, respectively, for SM; and 21.7%, 25.5% and 21.6%, respectively, for HF compared to C-CK; as well as 18.7%, 23.7% and 20.4%, respectively, for TS; 16.9%, 18.6% and 16.5%, respectively, for AF; and 16.1%, 13.0% and 13.9%, respectively, for RS compared to W-CK. These findings suggest that long-term CA application enhances the soil quality of the slope position, of which SM and TS applied to orchards and crop fields, respectively, are the most effective.