Effects of three herbivore species, four grazing seasons and three grazing intensity levels on a semi-arid rangeland in an adaptive management system were investigated using a 7-year grazing experiment in the Xilingol region of Inner Mongolia, China. The region experiences a semi-arid climate, with a mean annual temperature of-0.5„ƒ, and a mean annual precipitation of 315 mm, which mainly falls during the plant growing season from May to September. The rangeland is a typical steppe dominated by Stipa grandis and Leymus chinensis. A rotational grazing management with grazing duration controlled on the basis of grassland residual height was applied to adapt to the inter-annual variation in plant production. The results showed that cattle, sheep and goats had different preferences for plant species, and grazing by these herbivores at moderate grazing intensity drove divergent changes in species composition of vegetation. Grazing in different seasons at moderate intensity affects plant community structure and production mainly through altering the seasonal pattern of plant standing dead and litter, which impacts soil moisture capture and retention, and thus so il nutrient availability for plant growth; and by changing plant nutrient resorption and remobilisation, with autumn grazing having the least plant nutrient resorped in autumn thus negatively affecting plant growth in subsequent spring. Autumn grazing had the biggest adverse effect on plant community structure and production, while winter and early spring grazing promoted plant growth. Grazing intensity and precipitation jointly shape the compensatory growth and ANPP of the rangeland, with the highest ANPP occurring at relatively high grazing intensity and under high precipitation. Our results provide insights into the rangeland vegetation dynamics under different grazing regimes, and suggest that adjusting livestock composition can be used as a tool in rangeland management. Winter and early spring grazing was better than complete animal exclusion for grassland health, and an adaptive grazing management based on residual vegetation height is efficient for coping with the large inter-annual variation in climate and vegetation production in semi-arid rangeland region s. This paper collates and summarises findings from the study.
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