This study analysed the changes of the soil micro-ecology in the process of soil sterilization, green manure returning farmlands and fertilization. The methods of soil improvement was initially built which ensured the successful proceed of ginseng cultivation in farmlands. The soil chemical properties were analysed, the diversity and composition of bacterial community after soil sterilization, sterilization+green manure returning farmlands and sterilization+green manure returning farmlands+fertilization. The results exhibited that measures of soil improvement decreased the pH, increased soil fertility, declined the diversity of bacterial community and changed the composition of soil bacterial community. The comprehensive measures of sterilization+green manure returning farmlands+fertilization decreased the ginseng death rate compared to the control. Our data indicated that soil micro-ecological environment was changed by the treatments of soil sterilization, sterilization+green manure returning farmlands and sterilization+green manure returning farmlands+fertilization, and comprehensive measures improved the survival rate and guaranteed the development of ginseng cultivation in farmlands.

Through the development of ecological suitability analysis of producing area and the selection criteria of farmland cultivation in the global range of ginseng, we aim to provide scientific basis for rational planning, production layout and standardized planting of farmland. We analyze the data based on the ecological factors from 271 sample plots of Panax ginseng, including both the traditional producing regions recorded in past dynasties medicinal works and the popular production regions in the world, using global geographic information system for medicinal plant(GMPGIS) developed by ICMM (Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences). We concluded that the suitable producing areas in global for P. ginseng mainly included America, Canada, China, Russia, Japan, North Korea, France, Italy, Ukraine, and South Korea. In addition, the suitable producing areas in China mainly included Heilongjiang, Jilin, Liaoning, Shanxi, Gansu, Hubei, Sichuan, Inner Mongolia, Shandong, and Shanxi. Besides, based on the references and the experience of ginseng-producing and our many years' work on the 1,000-hectare plantation of P. ginseng, we established a standard land selection protocol for cultivation of P. ginseng. The use of GMPGIS to select the most optimum ginseng production regions provides a new scientific basis for introduction, cultivation, tending, protection, cultivation normalization for P. ginseng and the standard land selection protocol would lay a solid foundation for the high quality P. ginseng production.