放牧对温性荒漠草原植物群落特征与牧草营养品质的影响

为研究放牧对温性荒漠草原植物群落特征和牧草营养品质的影响，本文研究了放牧和围封对温性荒漠草原植物群落特征、牧草营养品质的影响及其相互关系。结果表明：放牧显著降低了植物群落的高度、盖度和生物量，显著增加了物种丰富度指数（P<0.01）；放牧显著增加牧草粗蛋白（Crude protein，CP）、粗脂肪（Crude fat，CF）、消化率（Dry matter digestibility，DMD）和代谢能（Metabolic energy，ME），显著降低了牧草的中性洗涤纤维（Neutral detergent fibers，NDF）和酸性洗涤纤维（Acid detergent fibers，ADF）（P<0.01）；群落多样性指数与牧草CP，CF，DMD和ME呈显著正相关（P<0.01），与牧草NDF和ADF呈显著负相关（P<0.01）；牧草CP，CF，DMD和ME与NDF和ADF呈显著负相关（P<0.01）。总之，放牧处理显著增加了物种丰富度指数和牧草营养品质。建议对围封温性荒漠草原进行适度放牧，以充分利用草地资源，保护草地物种多样性。

Effects of Grazing on Vegetation Characteristics and Forage Nutrientional Quality in a Temperate Desert Steppe

Grazing and fencing field were sampled to explore their effects on vegetation characteristics and forage nutritional quality by the combined analytical method in the temperate desert steppe. The results showed that, grazing significantly decreased the height, coverage and biomass of the plant community, and significantly increased the species richness index (P<0.01). Moreover, grazing significantly increased the Crude protein (CP), Crude fat (CF), Dry matter digestibility (DMD) and Metabolic energy (ME), and significantly decreased the Neutral detergent fibers (NDF) and Acid detergent fibers (ADF) (P<0.01). The species richness index was positively correlated with CP, CF, DMD and ME, but negatively correlated with NDF and ADF (P<0.01). CP, CF, DMD and ME were negatively correlated with NDF and ADF (P<0.01). In summary, grazing significantly increased species richness index and forage nutritional quality. Therefore, it is recommended to carry out appropriate grazing on the fencing temperate desert steppe to make full use of grassland resources and protect species diversity.