基于SIRMOD模型的不同耕作栽培方式的水分利用效率评价

利用SIRMOD模型对传统耕作(CONV)、垄作(FRB)、垄作固定道(PRB)、平作固定道(ZT)4种栽培方式下春小麦的水分利用效率进行了评价.结果表明:苗期计划层较浅,需要快速灌溉,PRB模拟灌水速度为3.83m3/s,CONV、FRB、ZT分别比PRB高出42.0%3、1.6%3、5.0%,渠系难以满足其要求,因此发生了深层渗漏,但以PRB渗漏量最少;在第2次灌水中,除PRB外其它3个处理均不能达到模拟灌水要求,均再次发生渗漏;以后几次灌水中再未发生深层渗漏,但灌水均匀度、入渗深度沟灌的都要比平作灌溉的好.PRB与其它3个处理相比,灌水速度要求低,发生的渗漏最少,用水量最少,保水能力强,水分生产效率最高(13.49 kg/mm.hm2).

Evaluation of water use efficiency in different cultivation systems based on the SIRMOD model

The SIRMOD model was used for comparison and evaluation of water use efficiency in four different cultivation systems,such as conventional tillage(CONV),fresh raised-bed(FRB),permanent raised-bed(PRB) and zero tillage(ZT).The results indicated that: the planned moisture layer of soil in seedling period was shallow during the first irrigation,so needed fast irrigation,the simulation irrigation speed for PRB was 3.83 m3/s,while the simulation irrigation speed for CONV,FRB and ZT exceeded that of PRB by 42.0 %,31.6 %,35.0 % respectively,but the canal systems was hard to meet the irrigation demand,so the deep seepage occurred,among which seepage loss of PRB was less than other cultivation systems.During the second irrigation just only the irrigation speed of PRB had reached the simulation speed,so deep seepage would not happen.During irrigations afterwards,deep seepage losses never happened once again,but irrigation evenness and irrigation quality of furrow irrigation were better than board irrigation.By comparison with other treatments,the simulation irrigation speed and deep seepage loss of PRB was least,and water use efficiency reached 13.49 kg/mm·hm2.