| 摘要: |
| 摘 要：【目的】利用主成分分析法对温室无风环境下的水面蒸发量（Ep）进行估算。【方法】基于温室内2020与2022年3—7月的实测水面蒸发量（Ep）与气象数据，采用主成分分析法对Ep受影响因素进行分析，利用提取出的主成分与Ep构建多元回归模型，并对估算结果进行验证。【结果】试验期间Ep随着试验时间的延长呈现上升的趋势，2020年与2022年3月的Ep均值分别为1.84 mm与1.94 mm，增加到6月的3.77 mm与5.15 mm；辐射因素与湿度对温室无风环境下水面蒸发量的影响占主要地位。其中光合有效辐射与水面蒸发量的相关性最高，相关系数为0.852（P＜0.01），其次为太阳辐射与湿度，相关系数分别为0.811与-0.770（P＜0.01）。第一主成分的太阳辐射、光合有效辐射以及湿度对水面蒸发量影响较大，特征值为4.44，其中太阳辐射对水面蒸发量影响最明显，得分系数最高，为0.328，湿度与光合有效辐射次之，得分系数分别为0.311与-0.321。基于主成分分析结果建立了的水面蒸发量估算模型，经检验，水面蒸发量估算值与实测值显著正相关（P＜0.01），方程决定系数R2为0.908，MBE为0.10，RMSE为0.48 mm/d，一致性指数较高（d=0.94）。【结论】在温室无风环境下太阳辐射、光合有效辐射与湿度对水面蒸发量影响较高，构建的基于主成分分析的水面蒸发量估算模型为实时获取温室无风环境下Ep动态变化及构建科学灌溉制度提供科学依据。 |
| 关键词: 温室；水面蒸发量；气象要素；多重共线；主成分分析 |
| DOI： |
| 分类号:P332.2 |
| 基金项目:河北省重点研发计划项目（21327005D）；国家重点研发计划项目政府间国际科技创新合作专项（2019YFE0125100）；河北省现代农业产业技术体系（HBCT2021200201，HBCT2021200202） |
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| Estimation and Verification of Greenhouse Pan Evaporation Based on Principal Component Analysis |
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王1,2,3
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1.Beijing Research Center of Intelligent Equipment For Agriculture, Beijing 100097;2. Inner Mongolia Key Laboratory of Soil Quality and Nutrient Resource, College of Grassland, Resources and Environment, Inner Mongolia Agricultural University, Hohhot 010018, China;3.College of Horticulture, China Agricultural University, Beijing 100094
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| Abstract: |
| Abstract: 【Background】Estimating pan evaporation(Ep) in windless greenhouse environment based on the principal component method.【Objective】The analysis was based on meteorological data and measured pan evaporation(Ep) from March to July in 2020 and 2022, and analyzed the Ep based on the principal component method. In addition, Ep estimation model was established by combining with multiple linear regression. 【Result】It was found that Ep increased as time elapsed, Ep averages was increased from 1.84 mm and 1.94 mm in March to 3.77 mm and 5.15 mm in June in 2020 and 2022 respectively; Ep in windless greenhouse environment is mainly influenced by radiation factors and relative humidity. Photosynthetically active radiation affected Ep most at significant level, correlation coefficient is 0.852(P＜0.01),and this was followed by solar radiation and relative humidity with correlation coefficients of 0.811 and -0.770(P < 0.01), respectively. The first principal component of solar radiation, photosynthetically active radiation, and relative humidity have a greater effect on Ep, eigenvalue is 4.44. Solar radiation had the most significant effect on Ep, with the highest score coefficient of 0.328, followed by relative humidity and photosynthetically active radiation, with score coefficients of 0.311 and -0.321, respectively. Estimation model of Ep based on the results of principal component analysis, verification proven that the estimated Ep was significantly and positively correlated with the measured values(P＜0.01), and the equation coefficient R2 was 0.908, MBE was 0.10, and RMSE was only 0.48 mm/d, the consistency index was 0.944.【Conclusion】Solar radiation, photosynthetically active radiation, and relative humidity have a greater effect on Ep in windless greenhouse environment. The Ep estimation model constructed based on principal component analysis provides a scientific basis for obtaining Ep dynamics under windless environment of greenhouse in real time and constructing scientific irrigation system. |
| Key words: greenhouse; pan evaporation; meteorological factors; multiple collinearity; principal component analysis |
