本研究采用SPAD叶绿素仪和酒精－丙酮浸提法测定河北沽源和内蒙古图牧集天然草原羊草的叶绿素SPAD值、叶绿素ａ、叶绿素ｂ和总叶绿素含量，探讨野外生态学实验采用叶绿素仪简便快速测定叶绿素的精确度。结果表明，在同一草原不同羊草个体之间羊草叶绿素含量和叶绿素SPAD值在一定范围波动，变异系数为20.457—36.921 %。河北沽源和内蒙古图牧集天然草原羊草叶绿素a、叶绿素b和总叶绿素含量随叶绿素SPAD值的增加而增加，呈线性函数、指数和幂函数规律变化，且均达到极显著相关水平，其中线性函数相关程度最大，可以更准确的预测羊草叶绿素含量。因此，可以利用SPAD-502叶绿素仪在野外条件下原位准确、快速地测定羊草叶绿素，为牧草生产实践提供理论依据

In order to discuss accuracy of determining chlorophyll with SPAD chlorophyll meter in the eecological field experiments, SPAD value, chlorophyll a, chlorophyll b and total chlorophyll content of Leymus chinensis on Hebei Guyuan and Neimeng Tumuji natural grassland were determined with SPAD chlorophyll meter and alcohol-acetone extraction method. The results showed that chlorophyll content and SPAD value of L. chinensis on different grasslands were changed in the certain range. The minimum value of SPAD value, chlorophyll a, chlorophyll b and total chlorophyll content of L. chinensis were 21.850SPAD, 2.611 mg?g-1, 1.125 mg?g-1, 3.738 mg?g-1, respectively. The max value of SPAD value, chlorophyll a, chlorophyll b and total chlorophyll content of L. chinensis were 46.150SPAD, 21.954 mg?g-1, 7.356 mg?g-1, 29.322 mg?g-1, respectively. Coefficient of variation was range from 20.457 to 36.921%. Chlorophyll a, chlorophyll b and total chlorophyll content of L. chinensis on Neimeng Tumuji natural grassland were higher than those on Hebei Guyuan natural grassland. On the contrary, SPAD value of L. chinensis on Neimeng Tumuji natural grassland was lower than those on Hebei Guyuan natural grassland. Regression Analysis showed that relationships between chlorophyll a content, chlorophyll b content, total chlorophyll content and SPAD value were significant linear, index and power function. Coefficient of determination was from 44.1% to 63.9. And the Coefficient of determination of linear function was highest than those of index and power function. SPAD502 chlorophyll meter can launch 660nm infrared light and 940nm near infrared light, which can reflect relative chlorophyll of plant. In result, chlorophyll content of L. chinensis Individual were different. Linear function could greatly reflect the relationships between chlorophyll content and SPAD value of L. chinensis. Chlorophyll content of L. chinensis can be accurately determined on field condition with SPAD chlorophyll meter. This method is Simple and fast on field experiment, providing theoretical basis for grass production.