Relationship between dust-retaining capabilities of photosynthetic organs and their surface properties of main shrubs species in Central Taklimakan Desert

Photosynthetic organs stained with dusts on the whole plant of ten kinds of shrubs planted in Tazhong Botanical Garden, near the Tazhong Si Oilfield, in the hinterland of the Taklimakan Desert, were sampled. Their dust-retaining capabilities of photosynthetic organs were analyzed by mass subtraction method. The results showed that the order of photosynthetic organ dust-retaining capability of ten species of shrub evaluated by means of monomial index of dust-retaining capacity in per unit fresh mass photosynthetic organs was Tamarix androssowii Tamarix hohenakeri, Tamarix hispida, Tamarix ramosissma, Tamarix elongata, Tamarix austromongolica, Tamarix juniperina, Tamarix taklamakanensis, Haloxylon ammodendron, Calligonum caput-medusae. Dust-retaining capabilities of photosynthetic organs of 10 species of shrub were closely related to their surface properties. Compared with Calligonum caput-medusae, Haloxylon ammodendro with assimilating branches, which has more shorter knot spacing and more leaves, exhibited higher dust-retaining capability of photosynthetic organs and Calligonum caput-medusae. Though leaves of Tamarix plants were also extremely degraded, they had excellent dust-retaining capability because of their photosynthetic organs, such as a mass of leaves, greater photosynthetic organs density, abundant tomenta, salt-secreting gland. Thus, their dust-retaining capabilities of photosynthetic organs were higher than that of Haloxylon ammodendron and Calligonum caput-medusae. Due to their surface properties, the dust-retaining capabilities of these Tamarix plants mentioned in this paper was different. The results provide a reference for tree species selection and allocation in landscaping and shelterbelt constructions, and research on correlation between plants and soils in arid regions.