Objective  Flower meadow is an attempt to simulate natural grassland community in urban. The competition of species in the meadow influences the presentation of community appearance during different periods, but here are few studies at present. Therefore, based on neighborhood interference model,our research tried to provide scientific support for competition in flower meadow community.

  Method  (1) Taking the annual mixed sowing combinations with different species numbers as an example, the species abundance and flowering period were investigated by sampling method every half month in the growing season, and the aboveground biomass was measured. (2) Four alternative models of neighborhood interference were selected to calculate and simulate the community competition intensity in Matlab software, the fitting accuracy of the models was compared and analyzed to obtain the best competition model, and competition intensity was calculated and the seasonal simulation and analysis were carried out.

  Result  (1) The best model of neighborhood interference was related to the size and distance of the object individual and neighboring plants, and the goodness of fit coefficient was 0.718 9. (2) About 90% of competition pressure in flower meadows was interspecific competition, the competition intensity of plants in underlying canopy of the community was increased gradually, and significantly higher than that in the tall overlying canopy and middle layer of the community, resulting in some species could not bloom normally. (3) The competition of communities became fiercer, and the species diversity increased firstly and then decreased, competition intensity and diversity of the mixtures with less richness were low, but the plant height and crown width of the species were larger. (4) Within a certain range, the increase of species diversity can reduce competition intensity of community, when the Patrick index was 8 to 10, Pielou evenness was about 0.46, Shannon-Wiener index was 2.1 and Simpson index was 0.82, the competition index in the flower meadow was the lowest, at this time, ratio of competition intensity in the middle and lower canopy of the community was 1∶3, the community was moderate-density, colorful and similar to the richness of natural grassland. Reliable guidance was provided in the study initially for the design of flower meadows from the perspective of community competition.