Study On Ecological And Biological Characteristics Of Ligularia Naryensis And Inter-specific Relation Between Qualified Forage

Ligularia naryensis, one of the main harmful species of rangeland, is perennial herb of Compositae, Ligularia Cass. This thesis takes L. naryensis in Karajun rangleland of Tekes County in Yili as object, by studying its ecological-biological characteristics, relations between other forage species, and exploring the propagation law of L. naryensis, which will effectively hold back its rapid spread, and provide a theoretical evidence to achieve the objectives of controling and exploring appropriate measures and ways. The main findings are as follows:1. Temperature is the main factor in the growing period of L. naryensis. Low temperature will delay turning-green of it, prolong nutritive period, and shorten flowering period. The aboveground and underground biomass growth of L. naryensis during the seedling, nutritive, flowering period, and bearing period shows a significant positive linear correlation (P<0.05).2. The changes in the important value of L. naryensis in natural rangeland basically consists with its height, diameter and density, which will surge in late May and get its peak in late June.3. The population characteristics of L. naryensis show within-fence < off-fence. The plant height, stem height, raceme length and capitulum number of the reproductive tillers are singnificantly higher than within-fence (P<0.01). The plant height, stem height, raceme length and capitulum number in the 3 kinds of elevations (1985m, 2280m and 2580m) have different degrees of difference, which show low-elevation> high elevation.4. L. naryensis seed number and thousand-seed weight show off-fence > within-fence; seed production in capitulum of different parts in raceme has position dependence, that is the top > middle> base.5. The gross of L. naryensis seedlings is large, while the survival rate is low throughout the growing season; there is no rules to follow the seedlings scattering direction besides the wind direction, which mainly arranges in the 0-40cm away from the stock plants.6. Reproductive allocation within the fenced adretto and shady slope, unfenced adretto and shady slope have no significant differences, between elevations show low elevation > high elevation; reproductive allocation was negatively correlated with its individual size.7. L. naryensis vaceme size and capitulum counterpoise show off-fence > within-fence; the number of capitilum shows adretto > shady slope (P<0.05). The raceme size and capitulum number show in low elevation > high elevation, however, capitulum counterpoise is in contrast, which show high elevation > low elevation.8. L. naryensis and Carex stenocarpa show significant negative correlation, and show significant positive correlation with Viola dissecta. L. naryensis shows significant negative coupling with Kobresia capillifolia, Potentilla sp., Alchemilla tianshanica and Achillea millefolium, not so significant positive coupling with Viola dissecta, Cerastium caespitosum.