Lawn most important role is to keep the water and soil, land cover due to a dense lawn and have flocculation roots in the topsoil layer, which has a good role in preventing soil erosion. Depending on the degree of soil erosion is rather sharply increase turf density. According to the research, different land surface 20 cm thick soil layer, the rain washed the net to make the required time, the grass was 3.2 years, while the bare land is only 18 years. Lawn can significantly reduce the diurnal temperature surface, thus effectively reducing soil soil due to "heave" caused by avalanche effect. Therefore, in our turf is also commonly used in the terraces, the embankment slope, received good results. Followed by purification of the atmosphere, the purification of the atmosphere mainly lawn lawn can be diluted, decomposition, absorption, fix atmospheric harmful, toxic gas, through photosynthesis turn harm into. According to the research, turfgrass can amines, hydrogen sulfide synthesis of protein; nitrate oxide can become useful toxic salts; convert carbon dioxide into oxygen. According to the calculation, 15 × 15 square meters area of lawn, release oxygen, enough to meet the needs of four people in a breath. Large lawn like a huge natural "cleaners", continuously receiving, adsorption, filtration of dust in the air. According to the Beijing Municipal Environmental Protection Research Institute in 1975-1976 showed determination, 3-4 in the wind, the bare dust concentration in the air around the lawn to have a concentration of dust in the air 13 times. Turf soccer field near the ground field loess dust content of only 1 / 3-1 / 6. Some turfgrass can secrete a certain amount of spinosad. According to the determination of bacterial content over the lawn, the only public places 1/30000. Therefore, the lawn is a natural air purifier. In addition, some lawn alarm can also play the role of environmental pollution, such as fescue can indicate air is zinc, the degree of lead, cadmium, copper and other pollution, and therefore the human environment or lawn sweeper and guards. So please be sure to take good care of the lawn, be more green ground.