Lake Zbęchy is situated in the General Chłapowski Landscape Park, which is the model of a rural area that has been subjected to agricultural pressure for many years. Over a thirty-year period (1976-2006) serious changes in the plant associations of Lake Zbęchy have occurred. The maximal depth of plant occurrence decreased from 3.6 m in 1976 to 2 m at present. The area overgrown by submerged macrophytes decreased from 13 to 0.2 ha. The community of