Differentiation of chlorophyll fluorescence parameters of six plants species in the Kubuqi sandy land

The PAM2100 portable chlorophyll fluorescence analyzer was used to measure and compare the chlorophyll fluorescence parameters of Artemisia ordosica, Caragana intermedia, Hedysarum laev, Salix cheilophila, Medicago sativa and Lespedeza davurica in the Kubuqi sandy land. This study showed that the minimal fluorescence (F0), the maximal fluorescence (Fm), the ratio of variable fluorescence to initial fluorescence (Fv/F0), the potential efficiency of primary conversion of light energy of PSⅡ(Fv/Fm), the photochemical quenching coefficien (qP), the nonphotochemical quenching coefficient (NPQ) and the actual photochemical efficiency of PSⅡin the light (Yield) was different among six plant species. Fm, Fv/F0, Fv/Fm, qP and Yield of C. intermedia, H. leave, S. cheilophila and A. ordosica were significantly higher than those of L. davurica and M. sativa. These results showed that the photosynthetic abilities of C. intermedia, H. leave, S. cheilophila and A. ordosica were greater than those of L. davurica and M. sativa, and the NPQ of L. davurica and M. sativa were higher than those of C. intermedia, H. leave, S. cheilophila and A. ordosica, indicating that L. davurica and M. sativa consumed excessive light energy by heat dissipation and protected photosynthetic organs from glare conditions in the sandy land environments.