Research On Growth And Propagation Characteristics Of Ephedra Intermedia And Its Influence Factors In Hexi Region

For the natural Ephedra intermedia seedlings in Hexi region, the above-ground part grows slowly while the underground root-system grows fast in the first year; it sprouts in March of next year and its high growth and tillering branches are obviously increasing, and April to July are the key seasons for the growth. In the third year, the high growth will be impaired while the tillering branches are still increasing several folded. When natural E. intermedia of three-year-old is cut at the end of October, its tillering and high growth speeds up in the next year after cutting, and the high growth will increase continuously in the second year, however, slower than that of the first year, and tillering branches will increase several folds. In the third year, the high growth becomes slow while the tillering branches are still increasing but tend to be slow. After 3 years, with the flourish fertile growth, the nutrition growth will be in a state of alternative of new and old. At the same time, tillering propagation will be intensified and the community will be expanded.Trails on the cutting of several-year-old E. intermedia showed: under the same site condition, the natural seedlings and re-growing grasses will reach maximum of its height after 3-year growth, and its height differences are not obviously. However, the tillering No. of branches of re-growing grass after cutting the several-year-old E. intermedia is difference obviously, and the latter is more than that of seedlings. The biomass has positive relation with the regulation of nutrition growth.The comparison of nutrition growth between natural and artificial E. intermedia shows: the biological height of E. intermedia are different under different habitat while the similar height under the similar habitat. However, the biological height of artificial E. intermedia is obviously higher than that of natural one, the difference is 22-23cm. Whatever natural seedlings, artificial seedlings, natural re-growing grass, or artificial re-growing grass, the tillering No. will rapidly increase year by year within 3 years, while the tillering No. of artificial one are much more than that of natural one. That is to say, under certain site condition, the biological height is fixed, while No. of tillering branches will change to an extent. So the yield will be greatly enhanced through improving habitat condition.The 3-year-old E. intermedia seeding begins to be mature physically and has there-growing grasses begin to flower and bear fruits partly in the second year, then, its fertile potential will be gradually intensified while their nutrition growth be impaired.E. intermedia, a plant without wide leaves, has small area for photosynthesis. The lacking of nutrition during fertility stage causes the decay of most of its flowers, which is a strategy for the living plants in survival competition. However, it has great flowering potential and strong fertility. Only if the nutrition provided enough during fertility stage can raise fruit-bearing rate obviously.The plant, with well-developed root system, is a root-tillering plant. It often grows in a form of community. Among the existing propagation styles of the species, root Propagation is the main one to extend its community and seeds can establish new communities. In a favorable habitat, with the root system expand, more tillering seedlings sprouting and the community domain will be expanded. At this time, the productivity of the community is much high and its ability of survival competition is strong, thus, plant species will be reduced. However, if the habitat is worsened, its community will become decay and other species will invade into the community.E intermedia in Hexi corridor is distributed in the 17 counties which is to the east of Jiuquan and to the west of Huanghe river. The east part of Hexi corridor, with the dominated soil of sand loam, light loam, loam and sandy soil, is the main area where natural E. intermedia is distributed and produced. The more to the west. The habitat becomes worse with thin soil and exposed sandy...