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土壤水分是中国北方旱区农业生产的主要限制因子,研究保护性耕作技术体系下土壤水分的动态变化,明确不同耕作模式下的水分平衡规律,对于选择适宜的保护性耕作技术,提高北方旱区土壤水分的利用效率具有重要的指导意义。该文在2a田间试验的基础上采用DSSAT模型对4个不同保护性耕作处理的土壤体积含水量、水分平衡以及水分利用效率进行了模拟和检验。结果表明干旱年份保护性耕作处理土壤体积含水量较传统耕作高,RMSE误差在0.025～0.063;干旱年份传统耕作土壤储水量减少最多,为144.6mm,降水较多年份减少也最多,为46.1mm;干旱年份水分利用效率1.52～1.78kg/m3,免耕覆盖水分利用效率最高,降水较多年份水分利用效率1.70～1.71kg/m3,各处理间差异并不显著。研究结果为保护性耕作技术对农田土壤水分的影响研究提供了理论依据。
Soil moisture is the main limiting factor of agricultural production in the northern arid region of China. The dynamic changes of soil moisture under the system of conservation tillage were studied, and the law of water balance under different tillage modes was clarified. It is of great significance to select appropriate conservation tillage techniques Soil moisture utilization efficiency has important guiding significance. Based on field experiments in field 2a, DSSAT model was used to simulate and test soil water content, water balance and water use efficiency of four different tillage treatments. The results showed that the soil moisture content of conservation tillage was higher than that of conventional tillage in the dry years, and the RMSE error was 0.025-0.063. During the dry years, the tilled water of traditional tillage decreased the most, at 144.6mm, and the precipitation decreased most frequently, which was 46.1mm. The water use efficiency was 1.52 ~ 1.78kg / m3 in arid years, and the highest water use efficiency was in no-tillage, the water use efficiency was 1.70-1.71kg / m3 in years with more precipitation, and the differences among treatments were not significant. The results provide a theoretical basis for the study of the impact of tillage technology on farmland soil moisture.