The Community Condition Of Stipa Breviflora Desert Steppe And Foraging Behaviors Of Goats And Sheep In The Winter And Spring

The community characteristics of Stipa breviflora desert steppe including height, coverage, abundance, frequency and standing crop were investigated and analyzed by using the"fixed sample lines". The dynamic variation of foraging behavior and livestock weight of grazing goats and sheep in the four flocks with different proportions of livestocks in winter and spring were also observed in the same area. The ratio of goats to sheep of the flocks were 1﹕0, 1﹕1, 1﹕3 and 0﹕1 respectively. The purpose was to provide basic and scientific data for the management and utilization to desert steppe reasonably. The main results were as follows:(1)The community characteristics: the average coverage, average density, average height and aboveground standing crop were 12.64%, 9.65 plants/m2, 7.30cm, and 244.60 kg/hm2 respectively. Some species like Stipa breviflora, Artemisia frigida, Cleistogenes songorica, Convolvulus ammannii, Kochia prostrata and Allium tenuissimum were dominant in the plant community. The frequency of these plants were about 80% and the sum of their aboveground standing crops made up to 92.01% of the whole.(2) The period rhythm of grazing goats and sheep in winter and spring in daylight showed that foraging behavior took longest time, wandering was secondary and fighting was least. The foraging time made up to over 70% of grazing period. The ratio of foraging time to wandering in initial grazing time had no significant difference between winter and spring, while there was significant difference between secondary grazing time and ultimate grazing time, and the ratio in spring is higher than in winter.(3) Different grazing seasons had a great impact on foraging behaviors and weight variation. Comparing spring and winter, intake per bite and daily intake (DM) decreased. However, the total bites and walking steps of whole day foraging all increased. In winter and spring, goats in both 1﹕0 and 0﹕1 flocks affected the desert steppe greater than sheep. In the 1﹕1 and 1﹕3 flocks, goats affected the steppe heavier than sheep in winter, and it was opposite in spring. Goats and sheep in the flock of 1﹕1 gave the least effects on steppe. The weight lost in this flock was less than in the others. So the ratio of goats to sheep in flock was condered reasonable and practicable.