【作者】 邓斌；

【导师】 马忠明；

【作者基本信息】 甘肃农业大学 ， 作物栽培与耕作学， 2007， 硕士

【摘要】 本文使用SIRMOD模型对垄作固定道(PRB)、平作固定道(ZT)、垄作(FRB)、传统耕作(CONV)四种栽培方式下春小麦的灌水进行指导,灌水后检测灌水均匀度,并用Enviroscan数据分析土壤水分动态变化,确定不同生育时期的灌水下限以指导灌水,并在水分利用效率和产量结果的基础上评价了不同耕作方式的优缺点,主要研究结果如下:Enviroscan检测的土壤水分达到下限则灌水,出苗～拔节0～40cm土壤水分下限为109.34mm、拔节至灌浆初0～60cm土壤水分以143.81mm为下限、灌浆初至成熟0～80cm土壤水分下限是190.52mm。计划层深度0～40cm、0～60cm、0～80cm的灌水量分别是56mm、84mm、112mm。灌水时间和灌水量确定后,用SIRMOD模型模拟灌水速度,用Oddysee量水灌水。苗期土壤计划层深度浅,模拟灌水速度要求最高,需快速浅灌,渠系一般不能满足要求,因此以最大灌水速度进行浇灌。SIRMOD模型每次灌水模拟速度要求高低为:CONV>ZT>FRB>PRB。模拟灌水速度对PRB要求最低,要求低、易实现。实际灌水总量与理论灌水量之差大小依次是:CONV>ZT>FRB>PRB。第一、二次灌水后各处理水分入渗均超过了计划层深度,地头入渗较深,含水量最高,地中次之,地尾最浅。PRB入渗超过计划层深度最浅,含水量最小。沟灌比传统灌水均匀程度高,且PRB灌水均匀度高于FRB。第二次灌水均匀度明显提高,由于灌水速度的要求下降,PRB首先满足了模拟速度。随着生育时期的推进,以后灌水的速度均满足模拟要求,水分入渗均未再超过计划层深度,灌水均匀度逐渐变好,入渗深度较均一。20cm、40cm处土壤水分比较活跃,70cm、100cm则相对较稳定,灌水前土壤水分下限不论是20cm还是40cm均以PRB较高。灌水后土壤含水量随着生育时期的推进逐渐下降,三个处理相比PRB日耗水量最小,CONV最大。在整个生育期PRB处理20cm、70cm、100cm土层含水量均比CONV、ZT、FRB高,40cm土层平均含水量比CONV略低,比ZT高5.82%,0～100cm土层平均含水量仍以PRB最高,可见PRB在整个生育期水分较充足。前茬作物收获后,各处理0～100cm土壤含水量随着土层深度的增加而变大,但处理间差异不大。冬灌时含水量变化趋势与前茬收获时相同,但PRB增幅最大,充分体现了保墑的能力。依据灌水指标,需要补灌的水量大小依次是:FRB>ZT>CONV>PRB。播种时表层PRB含水量最高。小麦拔节期,由于灌水的不同,土壤水分出现较大差别。灌浆期0～60cm平均含水量分别是22.96%、25.63%、26.29%、20.23%,处理间差异较大。叶面积和叶面积指数变化曲线呈抛物线状,单株叶面积除三叶期外CONV均小于其它三个处理,但由于其出苗率和分蘖率较高,提高了作物光能截获能力。叶—日积和产量成正相关,相关系数r达到0.935**,叶—日积对产量贡献大。PRB各生育时期干物质重最大,千粒重最高,植株矮小茎粗,抗倒伏能力强,且穗大粒饱;CONV出苗率、基本苗、茎蘖数、实际产量均在1%水平下达到显著,株高在5%水平下显著,产量6081.57kg/hm2分别高出其它三个处理14.58%、12.31%、14.26%,主要是其成穗数较高,弥补了自身的不足,且CONV的高产建立在大量灌水的基础上。PRB水分利用效率、全生育期灌水量和耗水总量与其它三个处理相比均在1%水平下显著,水分利用效率最高,比CONV高20.29%,PRB耗水量395.33mm,最少。PRB、FRB和ZT的籽粒产量处在同一水平,FRB和ZT耗水量和水分利用效率差异不大;总之PRB产量略低于CONV,水分利用效率远高于其它处理。更多还原

【Abstract】 In this paper, SIRMOD model was used to guide the irrigation of conventional tillage(CONV), fresh raised-bed(FRB), permanent raised-bed(PRB) and zero tillage(ZT) in Hexi Oasis Irrigation Area. Study dynamic water content by Enviroscan. Compare the change of water content in the same layers of four treatments. Soil moisture in the head, middle and end of field after irrigation was measured to analyze irrigation homogeneity, water use efficiency and the influences of yield in different treatment. The result show as following:According to Enviroscan data, during the period from emergence to jointing if soil water content in 0～40cm was 109.34mm plant need irrigated. From jointing to filling when soil water content in 0～60cm was 143.81mm plant need irrigated. If soil water content in 0～80 was 190.52mm plant need irrigated from filling to ripe. The irrigation water volume respectively was 56mm、84mm、112mm. Used SIRMOD to simulate irrigation speed, and used Oddysee to measure irrigation water speed.The plan depth is shallow when the first irrigation, so required fast irrigation. The simulate irrigation speed of PRB is 3.83 m3/s, the simulate irrigation speed of CONV, FRB, ZT more than 42.0%,31.6%,35.0% compared with PRB, but such speeds can’t come true, so replaced with the max speed of channel. Therefore, water volume irrigation is much more than water volume of deficit. When the second irrigation just only PRB could touch simulate speed, after second irrigation all can touch.Soi1 moisture was measured after irrigates the latter 48 hours. Compare irrigation uniformity of different treatments according to soil moisture of different layers, the uniformity of furrow irrigation was better than that of flat irrigation. Irrigation uniformity of PRB was better than that of FRB. The infiltration depth was deeper than depth of the plan. From head to end of the field the infiltration depth became shallower and shallower in board irrigation.When the last wheat was harvested soil moisture became more and more with deep from 0～100cm, but there was not much difference among different treatments. When winter water irrigation comed the change of soil moisture was nearly close in different layers, but water content of PRB was increased quickly. So it didn’t need much more water when irrigation winter. When sowing the surface soil was wetter, which better for emergence. According to water deficit index, the irrigation time was different, so the soil moisture of PRB is higher than other treatment whatever soil moisture of twenty or forty depth when jointing and filling. Dedicate that PRB was more power to gather and keep water. After irrigation the soil moisture was decreasing with time passing, but water consume of PRB is the least, CONV is the most. That’s to say PRB had enough water for plant during the period of growing. PRB could keep water high long time, so need irrigation water not much. But CONV need much more.There was better soil water content in ridge, so wheat grew healthy in PRB tillage, stalks and ears were in longer green stages, LAI、LAD and dry matter of PRB are higher than others, but LAD dedicate greatly for wheat yield and r was 0.935**. Plant of PRB was short but strong, so it wasn′t easy to lodge. Weight of one thousand seeds was heavier comparing PRB with others.PRB were superior to others in wue. Compared to CONV, FRB, ZT, wue of PRB was increased 25.5%, 42%, 40.5%. The water consumption was least, which was 395.33mm. CONV had the most yields, which was 6081.57kg/hm2, but the water consumption also was the most. It was 565.58mm, which was significant compared with others. WUE of CONV was 10.75kg/mm.hm2. WUE and the water consumption of FRB、ZT were very similar. WUE was PRB>CONV>ZT>FRB. Yield was CONV> PRB > FRB > ZT.更多还原