关键词: 生物膜, 生物膜, 毒力基因, 检测

Abstract: To study the role conversion of land-lost farmers in urbanization and analyze the transformation of China’ s economy and social structure, 150 farmers who were land-lost in the urbanization process of Laiwu city were investigated. The results showed that land-lost farmers faced problems such as relatively bald social role, simple and low hierarchical career choice in urban society because of the restrictions of personal experience, education background, personal preferences, age and so on. But social role in urban society was open and diverse, which could be a big challenge for land-lost farmers to adapt to urban life. Therefore, we put forward suggestions such as carrying out extensive vocational training and establishing a perfect social security system to promote land-lost farmers to convert their roles and realize the urbanization smoothly.