玉树隆宝地区光合有效辐射变化特征

Variation Characteristics of Photo-synthetically Active Radiation at Longbao, Yushu

为了研究长江源区光合有效辐射的变化特征,笔者利用玉树隆宝地区总辐射、光合有效辐射和空气湿度的观测资料,分析了该地区光合有效辐射和光合有效辐射系数的变化特征。结果表明：玉树隆宝地区光合有效辐射年总量13281 mol/m2,平均日总量38.2 mol/m2,年振幅26.7 mol/m2。光合有效辐射4月份最高,12月份最低,全年变化趋势和总辐射全年变化趋势一致。光合有效辐射系数的值为1.82~2.01 mol/MJ,在夏季略高,冬季略低,光合有效辐射系数与空气湿度呈正相关关系。利用观测资料得到光合有效辐射的估算方程,相对误差为4.35%。

In order to analyze the variation characteristics of photo-synthetically active radiation（PAR） at thesource region of Yangtze River, the author used observational data of total radiation, PAR and air moisture atLongbao, Yushu, and analyzed the variation characteristics of PAR and ratio of PAR to total radiation. Theresults showed that annual total PAR was 13281 mol/m2, the average daily total PAR was 38.2 mol/m2, annualamplitude was 26.7 mol/m2. PAR was the highest in April and the lowest in December. Annual variation trendof PAR was similar to that of total radiation. Ratio of PAR to total radiation was 1.82-2.01 mol/MJ and was highin summer and low in winter. Ratio of PAR to total radiation was positively correlated with air moisture.Estimate equation of PAR was established based on observational data and its relative deviation was 4.35%.