覆膜旱作水稻作物系数试验研究

Test for Crop Coefficients of Rice in Plastic Film Mulched Dryland

分析了覆膜旱作水稻需水量试验资料，得出覆膜旱作水稻各生育阶段综合作物系数。综合考虑了覆膜旱作技术对水稻生理生态的影响，提出了涵盖水稻冠层叶面积指数、天顶角绿叶覆盖串、含遮阴地表植被有效覆盖串及移栽后天数等稻株生长影响因素等综合作物系数计算公式。计算结果与实测值较吻合，经Ｆ检验具有极显著性水平，可以用于覆膜旱作水稻实际蒸发蒸腾量的计算。

The synthetic crop coefficients are evaluated by analyzing the experiment data on water requirement of rice in plastic film mulched dryland (RPFMD). In consideration of the effect of physiological and ecological indexes in RPFMD, the calculation formulas of the synthetic crop coefficient are proposed concerning on rice growth factors including canopy leaf area index, green leaves coverage of zenith angle, the effective fraction of soil surface shaded by vegetation and days after transplant. The calculation results are agreement with measured values, and the F test reaches an extreme significance level. The formulas are accurate enough to be applied to the calculation of actual evapotranspiration of RPFMD.