| With the rapid development of economy, large area of bare grounds, which are also called the man-made damaged surfaces, appeared in the process of large-scale construction and mining. Most of these man-made damaged surfaces couldn't be utilized because of its environmental particularity. As a direct result, environment problems like soil erosion and ecological damage deteriorated. Currently, the main defects of vegetation rehabilitation were poor acclimatization ability and singularity of plants, which would take a long-time and substantive capital. Therefore, the introduction of rock plants, which have strong resistance to drought and barren, might be a key to solve these problems.However most researches on rock plants both at home and abroad emphasized their individual characteristic, their acclimatization mechanism and great ecological potential were neglected. Therefore, ecology and nutrition characteristics, as well as drought resistance mechanism of rock plants were poorly understood. As an important rock plant, Pogonatherum paniceum(Lam.)Hack. is an international hotspot. Unfortunately most of researches on this issue were concentrated on conformation and classification, few studies on acclimatization mechanism and corresponding ecology and nutrition characteristics were reported.In this study, we chose Puyuan village of Bishan county, Laifeng town, Backhill of Southwest Agricultural University, and Jingyun Mountain as research sites. Ecology characteristics and nutrition demand of Pogonatherum paniceum(Lam.)Hack. was studied. Through the investigation on physical and chemical properties of its base rock, and combining with analysis of nutrient and water, its acclimatization mechanism was also studied.Ecological characteristics of Pogonatherum paniceum(Lam.)Hack. indicated that the transpiration was reduced by its small leaf area, and inner rock water can also be up taken because of its strong roots system. Therefore, it could grow on rock surface and rock aperture. The correlation analysis showed that coronal breadth of Pogonatherum paniceum(Lam.)Hack. was positively correlated with both rhizoma and plant height ( r=0.780**, r=0.387*), while the correlation between rhizoma and plant height was not so obvious. The results showed that root-top ratio was different at every period.Analysis on nutrient contents of Pogonatherum paniceum(Lam.)Ha.ck. showed that absorption of macro elements followed the order of N>K>Ca>S>Mg>P. Concentration of the same macro element varied significantly with different plant parts. As for N and P, the variation followed the sequence of flower > leaf > root > stem, and the order was flower > leaf > stem > root for K, as well as leaf > root > flower> stem for Ca. Maximum content of Mg was found in leaf whileminimum value was detected in stem. Meanwhile, contents of macro element were also different in the same plant part.Absorption of microelements by Pogonatherum paniceum(Lam.)Hack. also varied greatly. The order of microelement absorption was Fe>Zn>Mn>Cu>B>Mo. Contents of the same microelement varied significantly in different plant parts. Fe had the greatest difference, which it's higher in root and leaf while lower in floor and stem. Concentration of Cu followed the order of root > leaf > flower > stem, while that of Mn was leaf>flower>root>stem, Zn and B was leaf>stem>root>flower, and the content of Mo in each part was very low.Basic properties of rock samples showed that Pogonatherum paniceum(Lam.)Hack. could survive in soils with pH ranged from 4.32 to 7.66, and its rhizoshpere soil Eh is low (less than 300 mV). Porosity rate of rock was lower than the normal result (30%~50%). As for organic matter content, 26% of rock samples were categorized as scarce; another 26% was classified abundant while the rest were moderate. The contents of available nitrogen, available phosphorous and available potassium are similar to organic matter content. Moreover, the relationship between organic matter content and the above three factors appeared to be significantly...
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