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The value of the North American lawn |
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Page 7 of 11
Lawns accelerate organic chemical decomposition
Lawn soil food web offers one of the most active biological system for the degradation or sequestering of pollutants such as heavy metals, hydrocarbons from oil, grease and fuels, waste oils, paint thinners, preservatives, and solvents in the run-off water and sediment from impervious surfaces (Schuyler, 1987). Lawn soils support diverse community of microbes and non-pest invertebrates. The bacterial population in the moist litter, grass, clippings, and thatch of a lawn commonly is in the order of 109/cm2 of litter surface (Clark and Paul, 1970). A New Jersey Kentucky bluegrass/red fescue lawn supported 83 invertebrate taxa including insects, mites, nematodes, annelids, and gastropods (Streu, 1973). Dozens of beneficial species of rove beetles, ground beetles, ants, spiders, collembolans, and earthworms, are found in lawn soils (Potter, 1998). The average microbial biomass pool in grasslands is 1090 kg carbon per ha compared to only 700 in arable crops and 850 in forest systems (Smith and Paul, 1990). We have found that microbial biomass in lawn soils exceed 1140 kg carbon per ha in the Wayne County, Ohio (Singh and Grewal, unpublished data). Our preliminary studies reveal that lawn soil food web is also highly resilient to the impact of chemical inputs such as pesticides and fertilizers (Cheng and Grewal, unpublished).
Lawns reduce air pollution
Lawns improve air quality by stabilizing dust (soil erosion through wind) emanating from nearby roads, agricultural, and other non-turfed areas and removing carbon dioxide, smoke, and other air pollutants including allergy-related pollens (Beard and Green, 1994). A study also suggests that tall fescue a common lawn grass can capture even carbon monoxide, a major pollutant from the vehicle emission (Gladon et al., 1993). This area deserves more attention from the scientific community.
Lawns abate noise
Noise pollution is an environmental factor that has gained much attention in recent years. Studies on the acoustic properties of plants indicate that turfgrass is much more effective at absorbing sound than the trees which mainly act as scatters of sound. It has been found that the absorption coefficient, i.e., the fraction of incident sound which is totally absorbed at each single reflection, was superior for turfgrass than a heavy carpet on a felt pad (Robinette, 1972).
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