Structure of subterranean tree form buried sand on Juniperus sabina L. grown on the fixed sand dune at semiarid region in China

Abstract

Juniperus sabina L. is an evergreen shrub with prostrate life form that can effectively fix sand and is autogenous species at Mu Us Sandy Land in China and expects important tree species for revegetation. We dug for the individual growing on the southeastward slope of the fixed sand dune, and measured underground tree form and checked for the existence of adventitious roots. Based on these date, 3D tree form diagram was set out to clarify the structure of subterranean tree form on the fixed sand dune. The downward parts can’t observe in the pit. The underground parts formed two-stage stratified structure. Due to this subterranean tree form, the individual dug from the fixed sand dune had been growing above ground. These results show that J. sabina can survive after the axes buried by sand. Adventitious roots were located on the buried axes and the axes grew a reverse triangular pyramid shape underground. This growth occurred next to basal side where the adventitious roots exist. Some species in an environment with moving sand have been reported that the amount of growth increase with an increase biomass of adventitious roots from the buried main shoot. J. sabina is also suggested that the amount of growth increases by using adventitious roots on the buried axes. Characteristics of J. sabina for the sand burial would be associated with the fixation of the semi-fixed sand dunes.