玉树隆宝地区光合有效辐射变化特征

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13281mol/m²，平均日总量38.2mol/m²，年振幅26.7mol/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1.82~2.01mol/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%。

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

Using observed data of total radiation, photo-synthetically active radiation (PAR) and air moistrue at Longbao, Yushu, changing characteristics of PAR and ratio of PAR to total radiation are analyzed. The results show that annual total PAR is 13281mol.m-2, average daily total PAR is 38.2mol.m-2, annual amplitude is 26.7mol.m-2. PAR is highest in Apr and lowest in Dec. Annual variation trend of PAR is similar to that of total radiation. Ratio of PAR to total radiation is 1.82~2.01mol.MJ-1 and is high in summer and low in winter. Ratio of PAR to total radiation is positive correlated with air moistrue. Estimate equation of PAR was established based on observed data and its relative deviation is 4.35%.