The Impact of Different Aspects to Vegetation Characteristics and Composition in Stipa krylovii Steppe in Gacha Area—A Case of Alatantaogaotu Gacha, Abaga County

克氏针茅草原是旱生禾草草本群落，其旱生适应性强，在温带半干旱大陆性气候的锡林郭勒盟有广泛分布。坡向是重要地形因子之一，对克氏针茅草原植被特征和构成的影响较显著。本文选取阿巴嘎旗北部那仁宝拉格苏木阿拉坦陶高图嘎查坡向与对应植物为研究对象，基于数字高程模型(DEM)提取了研究区地形的坡向和实地调研样地数据，分析了二者的相关关系。结果表明：坡向的影响较明显，种的平均盖度为阴坡 > 半阴坡 > 半阳坡 > 阳坡，而相同坡向之间差异不明显，种的平均高度为阳坡 >半阳坡 > 半阴坡 > 阴坡，而相同坡向之间差异不明显。其优势种在阴坡上以禾本科的羊草、克氏针茅、碱茅、糙隠子草，莎草科的寸苔草，豆科的小叶锦鸡儿为主，半阴坡由禾本科的克氏针茅、羊草、冰草，莎草科寸苔草和菊科冷蒿构成，阳坡主要由禾本科的克氏针茅、羊草、糙隠子草、冰草，旋花科的阿氏旋花，藜科木地肤构成，而半阳坡则由禾本科的克氏针茅、羊草、芨芨草、糙隠子草，旋花科的阿氏旋花和菊科丝裂蒿构成。总之，克氏针茅草原不同坡向对草地群落植物种构成起着重要作用。 Stipa krylovii steppe is a herbaceous community of xerophytic grasslands, and its xerophytic adaptability is strong, and it is widely distributed in Xilingol League, whose climate is temperate semi-arid continental. Aspect orientation is one of the important topographic factors, and the in-fluence of the characteristics and composition of Stipa Kirschner vegetation is remarkable. This paper selects aspect and corresponding plant of Naranbaolag village, Altantaogaotu Gacha of the north of Abagaqa county as the research objects, and extracts the terrain direction and field data of the research area based on the digital elevation model (DEM), and analyzes the correlation between them. The results show that the effect of the aspect is obvious, the average coverage degree of species is shady slope > semi-shady slope > semi-sunny slope > sunny slope, and the difference of the same aspect is not obvious; the average height of the species is sunny slope > semi-sunny > semi-shady > shady slope, and the difference of the same aspect is not obvious. Among them, the dominant species of the species in shady slope are the grasses of Leymus chinensis, Puccinellia tenu-iflora, Ranunculaceae, Cyperaceae, and Caragana microphylla, semi-shady slope for Gramineae Leymus chinensis, Stipa krylovii, Agropyron cristatum, Cyperaceae carex and Composite constitute Artemisia; the sunny slope is mainly composed of Stipa krylovii, Leymus chinensis, Phalaris arundi-nacea, Agropyron cristatum, Convolvulaceae, Liliaceae and Chenopodiaceae, and the semi-sunny slope for Gramineae Leymus chinensis, Stipa krylovii, Achnatherum splendens, Phalaris spp, Convol-vulaceae and Asteraceae Compositae, In conclusion, the aspect of Stipa krylovii steppe plays an im-portant role in plant community composition.