| Depending on the planned irrigation moist layer depth can effectively regulate the spatial distribution of soil moisture, through soil water and crop root response relationship, and then affect the physiological growth of crops, affect crop yields ultimately. In order to determine Shi-yang River Basin main crops suitable irrigation decision, by setting different programs moist layer depth caused by the difference between the irrigation process, to investigate the relationship between the uneven distribution of water for irrigation of farmland soil and crop growth.In this study research the two main crops in northwest arid region of Shi-yang River Basin, discuss different programs moist layer depth on spring wheat and spring maizethe relationship between root zone soil moisturedistribution andgrowth. Get some conclusions as follows:(1) Based on SPSS cluster analysis, spring wheat0-100 cm depth soil moisturecan be divided into: surface layer 0-20 cm, shallow layer 20-40 cm, middle layer40-60 cm and deep layer 60-100 cm.Border irrigation maize 0-100 cm depth soil moisturecan be divided into: surface layer 0-40 cm, shallowlayer 40-60 cm, middle layer 60-80 cm and deeplayer 80-100 cm. Furrow irrigation maize 0-100 cm depth soil moisturecan be divided into: surface layer0-20 cm, shallowlayer20-40 cm, middle layer40-70 cm and deep layer70-100 cm.Spring wheat and Furrow irrigation maizemiddle layer were the main aquifer. Border irrigation maizeshallow layer was the main aquifer.(2)With soil depth increase, spring wheatsoil moisture unevenness enhanced. Advancing with crop growth, deep soil moisture reduced unevenness. Moist layer depth can effectively control the 0-60 cm range of soil moisture, with plans to increase wetting layer, different treatments decreased soil moisture differences. Spring wheat root mainly in 0-40 cm depth range, root length and root dry weight rendered more characteristics of a plurality of water, less irrigation treatmentmore likely to have deep rooted phenomenon. Confirmed moist soil moisture depth through regulate on the soil moisturedistribution can regulate on the root distribution.Different plan moist layer depth treatment, plant height and leaf area were different but not significant. Plant heightincreased most rapidly in jointing stage,different Treatmentsplant height and leaf areawere differences to water regulation stress responsesof irrigation control, lead to they are not synchronizedon irrigation response relationship. Ear length, stem length, kernel weight, 30 grain weight and yield were positive correlation with the growth period irrigation. Jointing- heading is the peak crop water requirement, at this stage soil water contenton the maximum yield of spring wheat. Different plan moist layer depth water consumptionshowed: Appropriate water deficit can increase the absorption and utilization of crop precipitation, water demand peakless irrigation likely to lead to early maturing wheat, yield decrease.(3) Border irrigation maize different treatments irrigation differencesdirectly lead difference of different depth layer soil water content, plan moist layer depth increases, the greater the impact of irrigation depth, the more obvious of the difference aquifer root.With water consumptionincreased, irrigation treatments on different depths soil moisture content decreased,but the soil moisture in vertical spatial differences will intensify at the same time.Maize roots mainly affected by soil water distribution, 0-50 cm depth was the main roots distribution layer,the main difference between different treatments roots level across 0-70 cm depth.Different plan moist layer depthtreatment plant height and leaf area were different and height difference was less than leaf area difference.Jointing stage is leaf areasensitive period,jointing- heading was height sensitive period.Different treatments stem weight, leaf dry weight, fruit weight and yield were positively correlated with the planned moist layer,different treatments yield and dry matter growth was not synchronized.When crops were water stress effective water utilization coefficient and irrigation water use coefficient were higher,appropriate deficit increased crop water absorption and utilization of precipitation.(4) Furrow irrigationnorth and south ditchirrigate at different time,Soil moisture trends not synchronized by Irrigation. Plan moist layer depth increases, the depth of regulation was greater, irrigation regulation on the low soil water was stronger.At the same time irrigation regulationenhance different sideditch soil moisture differences, resulting in varying degrees of water stress, improve crop utilization of rainfall and irrigation. Root dry weight rendered sequentially from shallow to deep reduction law,but treatment3 root dry weight appeared to increase in the aquifer,resulting in aquifer water consumption, leading to no significant rise in the aquifer after heavy rainfall,this was due to crop irrigation before soil above the aquifer water too low cause.Furrow irrigation different plan moist layer depthtreatment plant height was different, leaf area had significant differences.At the end of jointing stage to heading,with irrigation plan moist layer depth increase,the compensation effectof plant height increase was greater.Differenttreatments stem dry weight,panicle exhibited a positive correlation to planmoist layer.Different plans moist layer treatment conditionsyield and dry matter growth was not synchronized,at the same time the amount of dry matter and yield were not proportional.Maize formed fruit mainly concentrated in the grain filling stage. This stageshould ensure the crop water requirement.(5)Considering the effect of soil moisture, crop growth and yield growth period,spring wheat plan moist layer depthuse seedling 40 cm, jointing 50 cm, heading and after 60 cm not only to ensure crop yields, while achieving the purpose of saving water, irrigation is the best design.Spring maize plan moist layer depth use seedling 40 cm, jointing 50 cm, heading and after 60 cm was the best. |
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