Fatumah Nakiguli, Tilahun Seifu A, Mohammed Ssemwanga
College of Natural and Computational Sciences, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia.
College of Agriculture and Environmental Sciences, Makerere University, P.O. Box 7062, Kampala, Uganda.
Heliyon. 2021 Feb 27;7(2):e06308. doi: 10.1016/j.heliyon.2021.e06308. eCollection 2021 Feb.
With the increasing climate change impacts and variabilities, water is becoming a limiting factor for rainfed crop production in Uganda. Conservation tillage practices could improve soil and water conservation in croplands. Field experiments were conducted for three consecutive seasons from April 2019 to June 2020. The experiments evaluated the effect of soil tillage treatments on soil water storage, water use efficiency, grain yield, and economic benefits of the common beans ( L.) in two sub-counties of Mukono District, central Uganda. The soil tillage treatments were: no-tillage, stubble-mulching, deep tillage, and conventional tillage. The no-tillage and stubble-mulching improved soil water storage by 46 and 45%, respectively, compared with the conventional tillage in the 0-100 cm soil depth over the 14 months. Soil tillage treatments significantly ( < 0.05) affected the water use efficiency, with water use efficiency values generally higher under no-tillage and stubble-mulching than under deep tillage and conventional tillage treatments. The grain yield was highest under no-tillage and stubble-mulching than deep tillage and conventional tillage treatments, with over 5, 38, and 43% higher grain yield under no-tillage than under stubble-mulching, deep tillage, and conventional tillage treatments, respectively. Although no-tillage and stubble-mulching improved soil water storage and grain yield, seasonal precipitation distribution had a greater influence on the final grain yield, soil water storage, and water use efficiency. The net profit was 3 and 5 times higher under no-tillage than under conventional tillage and deep tillage treatments, respectively. The overall results showed that no-tillage and stubble-mulching were the optimum tillage treatments for increasing soil water storage and common bean yield, enhancing water use efficiency, and improving economic returns in central Uganda.
随着气候变化影响和变率的增加，水正成为乌干达雨养作物生产的限制因素。保护性耕作措施可改善农田的水土保持。于2019年4月至2020年6月连续三个季节进行了田间试验。试验在乌干达中部穆科诺区的两个乡评估了土壤耕作处理对普通菜豆（Phaseolus vulgaris L.）土壤储水量、水分利用效率、籽粒产量和经济效益的影响。土壤耕作处理包括：免耕、留茬覆盖、深耕和传统耕作。在14个月内，0-100厘米土层深度的免耕和留茬覆盖处理与传统耕作相比，土壤储水量分别提高了46%和45%。土壤耕作处理对水分利用效率有显著影响（P<0.05），免耕和留茬覆盖处理下的水分利用效率值总体高于深耕和传统耕作处理。免耕和留茬覆盖处理下的籽粒产量高于深耕和传统耕作处理，免耕处理下的籽粒产量分别比留茬覆盖、深耕和传统耕作处理高5%、38%和43%以上。虽然免耕和留茬覆盖提高了土壤储水量和籽粒产量，但季节性降水分布对最终籽粒产量、土壤储水量和水分利用效率有更大影响。免耕处理下的净利润分别比传统耕作和深耕处理高3倍和5倍。总体结果表明，免耕和留茬覆盖是增加乌干达中部土壤储水量和普通菜豆产量、提高水分利用效率以及改善经济效益的最佳耕作处理。
