The Fate of Nitrogenous Fertilizers Applied to Turfgrass

Abstract

Maintaining high quality surface and groundwater supplies is a nntional Concern. Nitrate is a widespread contaminant of groundwater. Nibogenous fertilizer applied to turfgrass could pose a threat to groundwater quality. However, a review of the fate of N applied to turfgrass is lacking, but needed in developing management systems lo minimize groundwater contamination. The discussion of the late o i N applied io iurfgsrass is developed around plant uptake, atmospheric loss, soil storage, leaching, and runoff. The proportion ofthe fertilizer N that is taken up by the turfgrass plant varied from 5 to 14% of applied N. Uptake was a function of N release rate, N rate and species of grass. Atmospheric loss, by either NH, volatilh t i o n or denitrification, varied from 0 to 93% of applied N. Volatilization was generally 4 6 % of applied N and can be reduced substpntially by irrigation after application. Denitrification was only found to be significant (93% of applied N) on fine-textured, saturated, warm soils. The amount orfertilizer N found in the soil plus thatch pool varied as a function of N source, release rate, age of site, and clipping management. With a soluble N source, fertilizer N found in the soil and thatch was 15 to 21% and 21 to 26% of applied N. respectively. with the higher values reflecting clippings being returned. Leaching losses for fertilizer N were highly influenced by f e r i i l i r management practices (N rate, source, and timing). soil texture, and irrigation. Highest leaching losses were reported at 53% , The discussion of the fate of N applied lo turfgrass will cover the five major categories of the N cycle: plant uptake, atmospheric loss, soil storage. leaching, and runoff. As illustrated in Fig. I, N can be found in both organic and inorganic forms in the turfgrass HE IMPORTANCE of maintaining high-quality sur-T face and groundwater supplies cannot be overstated. Groundwater accounts for 86% of the total water resources in the contiguous USA and provides Dep. ofFloricullure and Ornamcntal Honiculture. 20 Plant Sckmcs Bldg., llhaca. N Y 14853.

Nitrogen input from residential lawn care practices in suburban watersheds in Baltimore county, MD

“…The higher soil carbon content in the lawns surveyed, with the greater soil N content (r 2 ϭ 0.86) is supportive of the fact that soil quality may affect the amount of fertilizer that is applied to residential lawns. Further, Petrovic (1990) occurs within the first 10 years of turfgrass establishment. The age of development within the subdivisions with the lower soil N content and higher application rates of fertilizer were less than 10 years old at the time of this survey.…”

“…Plot-scale studies have shown that nitrate in run-off from fertilized turfgrass is not necessarily a constant source of nutrients to surface water but is temporally variable. For example, field studies have found low concentrations of nitrate in storm run-off from fertilized lawns (Petrovic, 1990;Garn, 2002), with the exception of storm events after fertilizer applications (Kelling & Peterson, 1975). For example, Line et al (2002), working in suburban sites in North Carolina, measured nitrogen concentrations to be four times higher in run-off from single family residential land uses during February compared to fall or winter concentrations.…”

Nitrogen budgets of urban lawns under three different management regimes in southern California

“…Excessive N inputs to lawns may enter groundwater as ammonium (NH 4 ? ) and nitrate (NO 3 -, Jiao et al 2004;Petrovic 1990) through leaching, causing threats to public health (Scanlon et al 2007), or enter the atmosphere through ammonia (NH 3 ) volatilization (Torello et al 1983) and emissions of nitrous oxide (N 2 O) and nitrogen monoxide (NO) in nitrification and denitrification (Bouwman et al 2002;Clayton et al 1997;Eichner 1990;Firestone and Davison 1989;Townsend-Small et al 2011). Kaye et al (2004) showed that urban lawns occupied 6.4 % of their study region of urban soils (including urban impervious, urban lawns, agricultural land, and native grassland) but contributed 30 % of the regional emissions of N 2 O, which is a powerful greenhouse gas (IPCC 2001).…”

Effectiveness of Grass Filters in Reducing Phosphorus and Sediment Runoff

“…Although the amount of rain can be high in some events as in August 8, 2006 (140 mm), the amount of generated runoff wasn't significant (57.6 m 3 ha −1 ) due to low rainfall intensity in addition to the effect of grass filters of reducing runoff velocity and increase infiltration. Petrovic (1990) and Erickson et al (2001) reported that little runoff was generated from turf grass surfaces compared to other land covers under natural precipitation. Heavier rainfall usually translates into more impact on the soil surface resulting in larger amounts of sediment being dislodged and carried away with runoff water.…”