不同耕作模式对土壤理化性状及旱地玉米产量的影响

为筛选北方旱农区适宜的耕作模式,在旱作大田条件下,通过4 a的田间试验,设置第1年深翻、深松、常规耕作(CK)和免耕,之后每年进行旋耕的4种耕作模式,研究了不同耕作模式下土壤蓄水保墒效果、土壤呼吸速率、玉米产量以及年纯收益的变化。结果表明,深翻模式具有较强的蓄水保水能力,可提高玉米产量,增加年纯收益,为最优耕作模式,实施后第2年土壤呼吸速率、玉米产量和年纯收益均达到最大,分别较对照提高28.78%,19.49%和33.71%;深松模式次之,免耕模式较差。第1年深翻,第2,3年旋耕的深翻模式为北方旱农区适宜推广的模式,其耕作周期为3 a,该模式对解决目前生产上由于土壤耕作方式单一引起的土壤耕作层变浅、结构破坏、蓄水保水能力变差等一系列问题具有重要的意义。

Effects of Different Tillage Methods on Soil Physical and Yield of Dryland Maize

To screen tillage mode suitable for northern China under dry farming conditions,through four years of field experiments,four cultivation patterns of deep plowing in the first year, subsoiling,conventional tillage and no-tillage in the later 3 years, and rotary till for the later years were designed to study the effects of water reserving and soil moisture keeping, content of soil organic matter, soil respiration rate, maize yield and annual net income changes under different cultivation modes. The result showed that as deep plowing mode with strong capacity of water storage could improve the soil fertility and maize yield, increase the annual net income, it is the optimal cultivation pattern. In the second year after the implementation, the soil respiration rate, maize yield and net income reached their maximum, increasing by 28.78%, 19.49% and 33.71% respectively compared with the control, followed by subsoiling pattern; while no-tillage mode was poor. Conclusion： The deep plowing mode that with deep tillage in the first year, rotary tillage in the second and third years is suitable for promotion of dryland farming areas in Northern China, the cultivation cycle is three years. The model is of great significance to solve a series of problems such as the shallow soil tillage layer, structural damage, poor water retention capacity, etc caused by a single soil cultivation mode.