A Study On The Dynamic Occurrence And Water Physio-Ecological Characteristics Of Turf Weeds

Through investigation, there are 82 species turf weeds in three different management level lawn community including species. There are 69 species turf weeds in worse management lawn community, 38 species in general and 37 species in better. In worse management lawn community Viola prionantha and Digitaria ischaemum are dominant weeds. Variation of important value of dominant weed is that in spring and fall the dominant weed is Viola prionantha while in summer it is Digitaria ischaemum. In general management lawn community it is Leymus secalinus that is the dominant weed in spring and fall and Digitaria ischaemum in summer. In better management lawn community Geranium sibiricum, Potentilla anserine and Leymus secalinus are the dominant weeds all the time and Geranium sibiricum is the most dominant weed.The regular pattern of Shannon-Weinor index of turf weeds in three different management lawn communities is that in worse community maximum Shannon-Weinor index appears in spring and fall but in better community is in late-summer and primary-fall.Genetic dynamic of weed can be divided in several phrases based on different management level and grow time: (1) annual weed stage; (2) perennial latifolious weed stage; (3) alternative stage between perennial latifolious weed and annual malignant weed; (4) alternative stage between perennial herb with rhizome and annual malignant weed; (5) alternative stage between perennial herb with rhizome and perennial latifolious weed.The sequence of diurnal changes of water potential of different plants in lawn community is: Potentilla anserine, Poa pratensisand, Potentilla supine, Leymus secalinus, Geranium sibiricum and Viola prionantha.The sequence of diurnal change of photosynthesis rate of different weeds in lawn community is: Potentilla supine, Geranium sibiricum, Viola prionantha, Poa pratensis and Potentilla anserine. ?The sequence of Diurnal change of transpiration rate of different weeds in lawn community is: Potentilla supine, Viola prionantha, Geranium sibiricum, Leymus secalinus J*otentilla anserine, and Poa pratensis .The sequence of Diurnal change of WUEph of different plants in lawn community is: Geranium sibiricum, Leymus secalinus, Potentilla supine., Viola prionantha, Poa pratensis and Potentilla anserine:The sequence of physiological drought resistance of weeds and turf in lawn community is: Poa pratensis, Digitaria ischaemumj'otentilla supine, Potentilla anserine, Viola prionantha, Geranium sibiricum and Inula britanica.Soil physical quality of better management lawm community is better than worse management lawm community. So plant in better management level lawn community can use water sufficiently.