Abstract:The result of pot culture experiments of lettuce in artificial climate cases indicated that the change of light intensity not only influenced the change of lettuce yield and the take up of soil nutrients,but also caused the change of nutrient content in different soils.the change of nutrient contents in three purple soils affected by light were that NH + 4 N and NO - 3 N contents were:in loarnic purple soil>sandic purple soil>gravelic purple soil,but the alkaline hydrolyzable N contents in them was:...