Abstract: In the light of the low survivial rate and slow growth of young Chinese arborvitae trees caused by drought in the loess plateau, the article studied the effects on soil moisture holding capacity and growth rate and photosynthetic rate after the ecomat was placed under the young arborvitae trees.The results showed that the ecomat didn't affect the soil moissture holding capacity,but made the young arborvitae tree grow faster and improved the Pn and Tr of the arborvitae tree leaves.

Key words: loess plateau, ecomat, the young Chinese arborvitae, photosynthetic rate