The Study On The Ecological Characteristics And Growth Of The Main Weeds In Lawns

The difference of environmental conditions obviously affects the growth of weeds in lawns. Viola prionantha Bunge mainly grows in the badly managed lawns, and Geranium sibiricum L.and Potentilla anserine L. are the dominating weeds in the better managed lawns. L.sacalinus (Georgi.)Tzvel mostly appears in the average-managed lawns. The tendencies of the quantity of the four kinds of weeds present the curves with "four-peak". The seasonal changes of population-quantity all take on four-peak curves. And the curves of Viola prionantha Bunge and Potentilla anserine L. are similar very much. According to the characteristics of density of seasonal fluctuations and the time in which weeds growth are in biggest density, the four kinds of weeds can be divided into two categories as following, (spring)summer type, including Geranium sibiricum L. and L.sacalinus (Georgi.)Tzvel, and Autumn type, including Potentilla anserine L. and Viola prionantha Bunge. The sequence of average size of four kinds of plants is Potentilla anserine L. > Geranium sibiricum L. > Viola prionantha Bunge. The seasonal tendencies of changes of individual-biomass are all one-peak curves, while Potentilla anserine L.and Geranium sibiricum L. are one-peak curves. The sequence of average speed of three kinds of plants is Viola prionantha Bunge > Geranium sibiricum L. > Potentilla anserine L.. The tendencies of the biomass and speed of different weeds have great differences, which take on several aspects as follows:(1) The sequence of average root - biomass of is Potentilla anserine L. > Geranium sibiricum L. > Viola prionantha Bunge. The seasonal tendencies of changes of root-biomass of three kinds of weeds are double-peak curves, which are similar very much. The sequence of average speed of three kinds of plants is Viola prionantha Bunge > Potentilla anserine L. > Geranium sibiricum L..(2) The sequence of average stem-biomass is L.sacalinus (Georgi.)Tzvel > Potentilla anserine L. > Geranium sibiricum L.. The seasonal tendencies of changes of stem-biomass of three kinds of weeds are all one-peak curves. The sequence of average stem-speed of three kinds of plants is Potentilla anserine L. > L.sacalinus (Georgi.)Tzvel > Geranium sibiricum L..(3) The sequence of average biomass-leaf of is Potentilla anserine L. > Geranium sibiricum L. > Viola prionantha Bunge > L.sacalinus (Georgi.)Tzvel. The seasonal tendencies of changes of leaf-weight Viola prionantha Bunge and L.sacalinus (Georgi.)Tzvel are double-peak, while Potentilla anserine L. and Geranium sibiricum L. are one-peak. The sequence of average growth-speed of leaf is Viola prionantha Bunge>L.sacalinus (Georgi.)Tzvel>Geram'H/77 sibiricum L.>Potentilla anserine L..(4) The sequence of average organ-biomass of four kinds of plants of sexual propagation is L.sacalinus (Georgi.)Tzvel > Viola prionantha Bunge, while biomass of flower and fruit of Potentilla anserine L and Geranium sibiricum L. are all in very low level( 0.01g). The tendencies of seasonal changes of organ-biomass of L.sacalinus (Georgi.)Tzvel, Potentilla anserine L.and Geranium sibiricum L. are all one-peak, while Viola prionantha Bunge is double-peak. The patterns of biomass allocation of four kinds of plants and their seasonal variation are largely different and every plant have obvious characters. The nutrient allocation of different leafy weed's leaf is the most and the stem of L.sacalinus (Georgi.)Tzvel is the most. The average ratio of root to crown of different leafy weed's leaf is between 27.7% and 32.84%. Geranium sibiricum L. is the lowest, while Potentilla anserine L. is highest. The sequence of allocation of nutrient matter of above-ground nutrient organ is Geranium sibiricum L. (69.3%)>Potentilla anserine L.(65.67%)> Viola prionantha Bunge (56.3%). The allocation of nutrient matter of nutrition-organ in different plant has obvious diversity, the relative weight of The bloom and fruit of Viola prionantha Bunge is 13.9%. Geranium sibiricum L. is only 3%, while Potentilla anserine L. is 1.49%.