Study On Reproductive Ecology Of Ceratoides Arborescens In Different Grassland

Ceratoides arborescens is endemic to China. It is widely distributed in Inner Mongolia, Jilin, Liaoning, Shanxi, Shanxi, etc. Ceratoides is mainly distributed in Mid-Eastern Inner Mongolia steppe. It often grows in fixed sand dunes, sandy land, wilderness or hillside. Results and main findings have great value of ecology and economy. The thesis studied on the characteristics of wild Ceratoides reproductive ecology in different habitats in Mid-Eastern Inner Mongolia steppe. The main results as follows:Observed results of the physiological phase showed that the flowering phases of the Ceratoides were from June to August, and longer, about 20 to 50 days.Findings of reproduction age showed plant diameter class was relation with capacity of reproduction. When diameter class r<1.33cm, Ceratoides did not enter into age of reproduction. One year old can enter into age of reproduction, but rare.Coverage and density of Ceratoides populations had bigger changes; Population density was 6.25-70.72 plants/m2 and coverage was 8-55%. Reproductive allocation of Ceratoides had negative correlation with community coverage (p<0.05). And it had negative correlation with fractionation coverage and relative coverage (p<0.001). Reproductive value of Ceratoides had negative correlation with population coverage and fractionation coverage (p<0.001). Reproductive value of Ceratoides had negative correlation with relative coverage; And it had positive correlation with population density(p<0.05).Under no having asexual vegetal circumstances, reproductive value of Ceratoides showed normal distribution or bias- normal distribution; Under having asexual vegetal circumstances, it had no remarkable change. With the change of the diameter, reproductive allocation value was from low to high to low. And reproductive allocation value had obvious difference in different habitats.Number of Ceratoides seedlings had correlation with topography. With distance of Ceratoides and ditch expanding, number of Ceratoide seedlings gradually cut down. They had obvious negative correlation (p<0.001). The natural germination of Ceratoides seed had positive correlation with soil water and correlation coefficient was 0.907**. It had negative correlation with distance of Ceratoides and ditch and correlation coefficient is -0.876**.The natural germination of Ceratoides seed had no obvious difference with soil nutrition.In different habitats, there's obvious difference in rate of fructify,seeds vigor and weight of 1000 grains of Ceratoides(p<0.05).