Confirm On The Beginning And Finishing Grazing-Period Of Spring And Autumn Pasture In Sagebrush Desert

Grazing is the most essential and significant means in the utilization of rangeland, and it is also the important reason to bring about degraded rangeland. Rational grazing-intensity and grazing-period are the keys to utilizing rangeland. In the research, the Seriphidium transiliens desert of northern slope of Bogedashan Mountain is selected to discuss the effect on spring and autumn pasture under different grazing intensity, in the hope of achieving the good circulation of rangeland ecosystem and improving the level of animal husbandry.The research results are as followed:(1) The growth curve of the rangeland was"double peak"type in a year. It is the same to the growth rhythm of Seriphidium transiliens. The peak was at the end of spring, the beginning of summer and autumn. The spring peak of Seriphidium transiliens is branching time; the autumn peak is blossoming and bearing time. It was nearly 1 month-long the dormant period in the summer. This kind of dormancy has a mainly influence on the summer high temperature, the growth of plants community are mostly influence by demobilize.(2) The extreme graze (EG) of the Seriphidium transiliens's fresh weigh and the dry weigh harvests maybe the middle graze (MG) 6.37, 8.80 times, the high graze (HG) of the Seriphidium transiliens's fresh weigh and the dry weigh harvests maybe the middle graze (MG) 4.11, 4.74 times. Although the middle graze (MG) to harvest the Seriphidium transiliens's dry weigh and the fresh weigh is all not highest, it is advantageous to the Seriphidium transiliens's regeneration, from the long-term consideration, the middle graze (MG) is advantageous to the Seriphidium transiliens's long-term using.(3) The Seriphidium transiliens's crude protein, the crude fat, the calcium, the phosphorus in the spring are higher than the autumn; But the crude fiber and the thick ash content in the spring are lower than the autumn. In the soil moisture content over all the spring is bigger than the autumn, and along with the grazing time and the time continuing, the soil moisture content by the level of rising tendency. The unit weight in springtime of enclosure outer is higher than the enclosure inner, the unit weight in autumn of enclosure outer is lower than the enclosure inner. (4) In the spring and autumn (Seriphidium transiliens) in sagebrush desert area, it is the rational beginning grazing period of spring and finishing grazing period of autumn is from April 15th to May 15th and from October 1st to November 1st.