| Artemisia sacrorum steppe of the Inner Mongolia distribut mainly in the steppe region of the mountain area (southern of Daxinganling mountain, mountain area of northern Hebei, Daqing mountain, Manhan mountain), as well as the loess hill-gully region (loess hill-gully region of western Liaoning and loess hilly-gully region of southern Yinshan mountain). Artemisia sacrorum community is one of the natural plant communities which need to focus on in the vegetation restoration of ecologically fragile zone in the Loess Plateau. As one of the important gully vegetation type, which has a very important role in reducing soil erosion and improving vegetation biodiversity. So by deeply investigating and measured community characteristic,population characteristic,root distribution and physiological and ecological characteristics, we just tried to provide scientific basis for the rational use of plant resources,vegetation construction and soil and water conservation in the loess hilly-gully region. The main results are as follows:1. Arsenic rock matrix have higher water content, complex soil mechanical, gravel and coarse sand with a higher level, higher soil erodibility; Loess matrix have lower water content, more fine sand, lower soil erodibility. But these two matrixes are both high soil erodibility.2. Artemisia sacrorum community in the research region are distributed in hilly slopes,sunny slopes and shady slopes, but its distributed the most widely in the shady slope. Communities in the arsenic rock matrix with higher water content have significantly higher biological diversity and biomass per unit area than that of loess matrix, and the more complex type of composition. Communities in two habitats on the cover is higher, the loess habitat of about 50%, and the arsenic rock and hilly slopes with better moisture conditions of more than 80%.3. Artemisia sacrorum average biomasses in the two habitats reach maximum in the age of 7,8, and the difference is not obvious. Age structures of Artemisia sacrorum populations in the two habitats are stable in the arsenic rock matrix, and growth in the loess matrix. The R: S of Artemisia saerorum is relatively small. Artemisia sacrorum early as age 5 can carry out sexual reproduction, fruit bearing amounts in the arsenic rock and loess habitats reached 20,597 (tablets / m~2 ) and 18083 (tablets / m~2 ); Artemisia sacrorum begin to emerge from the vegetative propagation in the age of 4, the total length buried away from the main stem branches were 91.44 (cm/m~2) and 32.32 (cm/m~2), and reach the maximum between the age of 6-8. And its perennial branches buried about half a month can produce adventitious roots.4. The roots of Artemisia sacrorum have a main root in the age of 1, but begin to weaken, decay, and produce adventitious roots in the age of 2; Adult-oriented individual mainly with adventitious roots. Roots are mainly distributed in the 0-20 cm, account for about 90% of the total; to about 50 cm is basically no distribution of the roots. Between the weight and length of Artemisia sacrorum fine roots has a significant linear correlation, the root length in the 0-20cm account for about 75% of the total length. The length of Artemisia sacrorum fine roots (<1mm) is the longest, account for around 75% of a total length of the root system.5. Artemisia sacrorum changes in net photosynthetic rate curve as a "single peak" curve, to 10:00 or so to achieve maximum net photosynthetic rate, no "nap" phenomenon. Artemisia sacrorum on transpiration rate curve is also the "single peak" curve, to the maximum at 12:00 or so. PAR is the most important environmental factors impact on net photosynthetic rate (Pn) and transpiration rate (Tr) in the region. The water use efficiency (WUE) maximum of Artemisia sacrorum appears around 8:00 in the morning, and the WUE of Artemisia sacrorum is low overall.
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