Changes in weed community diversity of maize crops due to long-term fertilization

The effects of various fertilization treatments on weed species composition and diversity were investigated in experimental plots of summer maize established 14 years previously in Fengqiu, China. The treatments examined influenced weed flora composition and density. Multivariate analyses showed that changes in the weed community composition were primarily due to available soil P, followed by available soil N. Omission of N-, P-, and K-applications decreased weed diversity and/or inhibited the presence of many weed species, while greater weed species diversity but reduced density occurred when N, P, and K were applied together. Nutrient source from synthetic fertilizers and organic manure had no effect on the weed community diversity. (c) 2006 Elsevier Ltd. All rights reserved.