| Two measures of ridge (R) and flat (F) film mulching are adopted, taking traditional cultivation as the control, determination and analysis the soil temperate, soil moisture dynamics, and sensitive indexes of winter wheat under four film mulching treatments in farm land of Yangling, Shaanxi province. Studied the soil moisture conservation viaincreasing soil temperature effects, the results of study is perfecting and optimizing the film-covering planting techniques and have important theoretical and practical significance, and to investigate the rational film-covering planting pattern for sub-humid areas of Loess Plateau.1. The different film-covering planting have different effects of0-200cm vertical distribution of soil moisture in different period, and the different treaments have similar trends in same period, the soil moisture make a great difference in the shallow layer (0-60cm) of earlier growth stage and deep layer of late-mid growth stage of winter wheat. Compared to traditional cultivation (CK), in the whole growth period, the0-200cm soil moisture content of film-covering treatments is higher, not significantly. And with the wheat stage getting faster, the water deprivation is increase, and the film-covering treatments is increase, significantly. Compared with CK, the building areas of R40and R60treatments respectively increase by8.82%and10.84%, film-side areas increase by8.83%(P<0.05) and12.03%(P<0.01), and film-inside areas increase by10.46%(P<0.05) and14.88%(P<0.01); the building areas of F40and F60had4.40%and3.96%improvements, film-side areas had3.35%and4.87%, and film-inside areas had5.38%and6.06%(P<0.01). The building areas of R treatments is averagely increase5.42%(P<0.05) with F treatments, film-side and inside areas respectively increase by5.83%and6.56%.2. The0-40cm soil available and total nutrients contents of film-covering treatments were gradually reduced with the soil layer deeper. Compared with preplant soil, available K content of each treatment was decrease significantly; Available P only R treatment was increase in0-20cm soil layer; Available N of each treatment in each soil layer was increase, and the rate of increase was increase with depth.The effects of film-covering on total nutrients is lower than available nutrients, and each total nutrients of each treatments were decrease. After the wheat harvest, the organic matter of each film-covering treatments in20-40cm layer was increase39.29%in average, significantly; The total N and P of each treatments in0-40cm layer with little changes, and total K with a great variation,0-20cm soil layer decreased10.03%～16.31%and20-40cm increased2.37%～10.40%.3. For different film mulching modes, net photosynthetic rate (Pn), transpiration rate (Tr) and stomatal conductance (Gs) were significantly (P<0.05) higher than those of control, and reduce gradually with the advance of the growth stages, the order of each treatments is: Heading>Flying>Filling, the order of each treatment’s Pn, Tr and Gs in each stage is:R60> R40>F40, F60>CK, and the R treatment significantly higher than F under the same film mulching width, the intercellular CO2concentration (Ci) was significantly lower than CK (P<0.05) and increase gradually with the advance of the growth stages, the order of each treatments is:Filling>Flying> Heading, he order of each treatment’s Ci in each stage is:CK>F40, F60>R40>R60.4. For different film mulching modes, the SPAD value were get a slight increase first and then decline rapidly with the advance of the growth stages, the Flying stage is highest, and the lowest is Filling stage. The order of each treatment is R60>R40>F60>F40>CK in Heading and Flying stage, the film-covering treatments is increase significantly with CK, and the R treatment significantly higher than F under the same film mulching width.5. The application of film mulching modes makes different effect to soil temperature. The effect gradually reduced with the soil layer and the time increase, the thermal preservation effect weakened with temperature increase. The results showed that the prophase thermal preservation effect of F treatment, R followed, and all higher than CK; in anaphase, the soil temperature of each film-covering treatments was decrease with rise of temperature. Compared with CK, the5-25cm soil temperature of R40、F40、R60and F60increased by0.42℃、0.58℃、0.60℃、and0.75℃in seedling stage, decreased by1.07℃、0.96℃、0.99℃and0.41℃in heading stage, decreased by2.50℃、1.76℃、2.58℃and1.43℃in mature stage.6. The economic yield and WUE of winter wheat under different film mulching modes were significantly higher than CK, which average increasing rate were21.52%and30.97%. the biomass yield of R40、F40、R60and F60increased23.81%(P<0.01),8.08%,25.64%(P<0.01) and6.68%; economic yield increased710.43kg·hm-2(19.54%),1458.58kg·hm-2(40.13%),105.50kg·hm-2(2.90%) and115.26kg·hm-2(3.17%); WUEY increased2.92kg·hm-2·mm-1(28.46%),0.61kg·hm-2·mm-1(5.91%),5.76kg·hm-2·mm-1(56.03%) and0.73kg·hm-2·mm-1(7.07%); water consumption decreased24.28mm (6.85%),10.85mm (3.06%).35.73mm (10.08%) and12.76mm (3.60%). Compared to the F treatment, the biomass, grain yield and WUE respectively increased under corresponding R treatment, increase significantly about16.16%,26.00%and33.51%on an average. |
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