To take an extreme example, farmlands dominated by a single crop are so unstable that one year of bad weather or the invasion of a single pest can destroy the entire crop. In contrast, a complex climax community, such as a temperate forest, will tolerate considerable damage from weather to...
施工现场应设“五牌一图”具体是指？六牌”是：工程概况牌、安全生产牌、文明施工牌、消防保卫牌、管理人员名单及监督电话牌；“一图”是：施工现场平面布置图。