Abstract:

4 plant species arranged in groups were used in this test, including Artemisia desertorum, Caragana tangutica, Hippophae rhamnoides and Achnatherum splendens, for simulating aerial seeding in sand of the upper reaches of Yellow River. 4 types of site preparation, I.e. barrier, ditch, hole and no preparation (CK) were selected. 7.5, 15, 20 g·kg^-1 contents of absorption agent were selected also for treating the seeds. Simulating aerial seeding was tested by multiple factor design on left bank sands of Longyangxia Yellow River, The survey and statistical analysis of the random samples were made after autumn. The results showed that the average emergence rate of various plant species was 2 811 seedlings per hectare in the test of aerial seeding, among which H. rhamnoides amounted to 6.6%, C. tangutica 0.1%, A. desertorum 91.2%, and 1.2% for A. splendens, indicating that the A.desertorum seeds were best suitable for aerial seeding in the experimental region, and A. splendens seeds could be used as species arranged in groups, and the seeds of H. rhamnoides and C. tangutica should be used in direct seeding planting. The emergence rate of aerial seeding increased with the increase in the amount of absorption agent. The artificial site preparation created a favourable conditions for the germination of seeds by aerial seeding, however the cost of aerial seeding in a large area would be increased. Both A. desertorum and A. splendens are drought-enduring plants, and thousand kernels weight (TKW) of their seeds are extremely light. It is very economical to seeding them with ultra-low aerial seeding.

Key words: Artemesia desertorum, Achnatherum splendens, Hippophae rhamnoides, Caragana tangutica, simulating aerial seeding, sands, upper reaches of Yellow River