滨海低平原干旱区全膜覆土穴播冬小麦田水热特征和产量效应

Effect of whole filed plastic mulching with bunch planting on soil thermal-moisture characteristics and winter wheat yield in the lowland plain of Hebei Province

  • 摘要: 为研究全膜覆土穴播栽培技术在环渤海低平原区对冬小麦田土壤水分、盐分、温度、热量状况和冬小麦产量的影响, 采用田间试验法, 于2014—2015年在中国科学院南皮生态农业试验站, 设置全膜覆土穴播(PM)和常规旋耕播种(CK)冬小麦试验, 定位监测了耕层土壤温度、水分、盐分和热通量数据动态, 并分析了冬小麦产量。结果表明: PM在越冬期和返青期可以有效保持土壤水分, 平均土壤含水量比CK高16.4%,达显著性差异(P<0.05); 但是, 覆膜也阻隔了后期降水对土壤水分的补充, 最大含水量差异可达10.0%。PM处理10 cm深土壤日均温度始终高于CK处理, 平均增幅3.8%, 差异不显著(P>0.05); 同时, PM减小了土壤温度日较差0.5 ℃。PM有利于土壤吸收和储存热量, 白天具有较高的向下地面热通量, 日均土壤热通量比CK显著增加数倍。温度和热通量变化均表明覆膜增强了土壤抵御外界温度变化的能力。PM的土壤电导率显著低于CK 24.2% (P<0.05), 特别是在春季返盐期, PM的土壤电导率比CK降低39.7%。PM较CK增加了冬小麦穗粒数和千粒重, 增产10.4%, 但均未达显著水平。因此, 全膜覆土穴播冬小麦栽培技术能改善土壤水热状况, 降低土壤盐分对小麦的危害, 这为全膜覆土穴播冬小麦栽培技术在环渤海低平原干旱区农业生产中的应用提供理论与技术支持。

     

    Abstract: The objective of this study was to clarify soil water, soil salinity, soil thermal characteristics and yield of winter wheat in Hebei Lowland Plain under total soil-plastic mulching with soil covering and bunch planting. The study was carried out at Nanpi Eco-agricultural Experimental Station of Chinese Academy of Sciences in 2014–2015. Two treatments included the treatment of plastic film mulching the entire soil surface with bunch planting (PM) and the treatment of rotary tillage with traditional seed planting as the control (CK). Soil moisture content, soil salinity, soil temperature and heat flux was monitored from winter wheat seedling emergency to harvest. Winter wheat yield plus yield components were analyzed too. The results showed that PM improved soil moisture in the topsoil during wintering and re-greening stages. Although soil water content was higher by 16.4% under PM treatment than the CK treatment (P < 0.05), plastic mulching restricted precipitation water supply by up to 10% after re-greening. PM improved soil temperature of the 10 cm deep soil, with average soil temperature increment of 3.8% for the entire growing season (P > 0.05). Also PM reduced diurnal range of soil temperature by 0.5 ℃, compared with CK. PM favored the absorption and storage of heat energy, with 14.8 Wm2 more soil heat flux in PM than in CK during the whole growth period. The mean daily soil heat flux under PM increased by several folds over that under CK during daytime, which showed that PM increased downward flow of heat energy. The changes in temperature and heat flux showed that the total plastic mulching enhanced soil ability to resist ambient temperature changes. Electrical conductivity in the topsoil was significantly (P < 0.05) lower by 24.2% under PM than under CK during the whole growing season. It showed that PM generally restrained salt accumulation at surface soil. PM increased kernels per spike and 1000-kernel weight of winter wheat compared with CK. The yield of winter wheat increased by 10.4% under PM compared with that of CK (P > 0.05). This study provided theoretical and technical support for the application of total plastic mulching in winter wheat fields in coastal plains of Bohai Sea.

     

/

返回文章
返回