棉田滴灌水盐模型及动态变化规律

Experimental Research on the Soil Water-salt Model and Transport of Saline in Cotton Field under Drip Irrigation

建立了棉田滴灌条件下土层盐分平衡方程,对不同盐渍程度的棉田土壤水盐动态变化进行了初步研究。结果表明,滴灌能够降低地下水和土壤中的总盐含量,使地下水中的总盐含量保持在3.0g/L左右,土壤中CI-和SO42-含量变化趋势和总盐含量变化一致;土壤含盐量主要集中土壤表层0～25cm,0～100cm土壤含盐量呈指数函数关系,经模型验证与实测值较为吻合;土壤的含盐量直接影响棉花的出苗率、生长发育和生理特性,进而影响棉花的产量和品质。研究为土壤盐碱化防治和棉田水分管理提供科学依据。

In order to lower the salinity to cotton produces and enhance water use efficiency in south Xinjiang, we experiment on cotton field of drip irrigation in Alar of south Xinjiang. Based on experimental data, the variation laws of ground water salt content and level and soil salt content were analyzed. The empirical formulae for calculating the soil salt content were presented etc. The results show that the groundwater salinity and soil salinity was reduced and the groundwater salinity was keep 3.0 g/L under drip irrigation. The laws are sameness Cl^- and SO4^2- in soil with soil salinity. The soil salinity mainly concentrates soil surface layer 0-25 cm, and soil salinity underground 0-100 cm is exponent relation. The model computes values are closed to measure. The research enunciation that cotton characteristic and yield are influenced by soil salt content. The results provide science basis for prevention the soil salt and the humidity managemeNt of cotton farmland.