Environment Contamination Potential Of Fertilizers And Pesticides Used On Golf Course

Limited information existed on the leaching and environmental impact of fertilizers and pesticides applied to golf course under conditions in China. This study, conducted in 2004 at the Beijing Forestry University Turfgrass Institute Research Facility, China, was to determine Leaching and movement of fertilizers and five pesticides commonly used on golf green turfgrass at Beijing region using field bucket-type lysimeters. The two fertilizers used in the experiment were urea and potassium dihydrate phosphate. The five pesticides used in the experiment were metalaxyl, carbendazim, chlorothalonil, qudintozene and furadan. The surface water non-impact application rate of urea, potassium dihydrate phosphate and five pesticides were also studied. Surface water quality and carbendazim, chlorothalonil, qudintozene, furadan residue in the surface water of eight golf courses at Beijing were investigated. And the results were compared with that determined by field bucket-type lysimeters. The conclusions reached include the following:â… . Nitrate in the root-mixture move downward rapidly, nitrate content in the 20-30cm root-mixture was related to nitrogen application rates. Nitrate content in the 20-30cm root-mixture also changed at different season but reached maximum at July despite nitrogen was applied at various rates. Annual average nitrate content in the 20³0cm root-mixture can be predicted by nitrogen X₁ (N) and phosphate X₂(P₂O₅) application rate with a linear equilibrium model:Y =31.231+14.136 X₁-0.214 X₂+4.467 X₁²+1.139 X₂²+0.186 X₁ X₂.â…¡. Nitrate concentrations in the leachate were also related to nitrogen application rates, Nitrate concentrations in the leachate increase with the accretion of nitrogen application rate. Nitrate concentrations in the leachate were not effected by increasing phosphate application rate if nitrogen applied at low rate (20 g/(m².yr)). While nitrogen applied at 33 g/(m2.yr), 40 g/(m2.yr) or even higher, increase phosphate application rate will reduce nitrate concentrations in the leachate. Nitrate concentrations in the leachate can be predicted by nitrogen X₁ (N) and phosphate X₂ (P₂O₅) application rate with a linear equilibrium model:Y =35.939+26.041 X₁-4.426 X₂+5.747 X₁²-1.812X₂²-5.659X₁ X₂. With monthly nitrogen application rate on golf course under 4.7 g/m², the nitrate concentration in the leachate would not exceed 25mg/L, so it did not contaminate surface and ground water quality on golf course.â…¢. Nitrite nitrogen content in the 20³0cm root-mixture were not related to nitrogen and phosphate application rates. Nitrite and ammonium concentrations in the leachate were generally below 0.06mg/L and 1.0mg/L respectively throughout of the experiment, ammonium concentrations in the leachate changed with different season and reached maximum at July, while nitrite concentrations in the leachate had no seasonal variety. Nitrite and ammonium in the leachate from golf green root-mixture did not contaminate surface and ground water quality.â…£. Available phosphorus content in the root-mixture reduced from top root-mixture to 20³0cm root-mixture. Annual average available phosphorus content in the 20³0cm root-mixture can be predicted by nitrogen X₁ (N) and phosphate X₂ (P₂O₅) application rate with a linear equilibrium model:Y =5.618-0.202 X₁+3.918X₂+0.063 X)1²+1.372X₂²-0.247 X₁ X²Available phosphorus content in the 20-30 cm root-mixture had no seasonal variety on the 5g phosphate (P₂O₅) m^-2 .yr^-1 and 20g phosphate (P₂O₅) m(-2) .yr^-1 plots, while available phosphorus content in the 20³0 cm root-mixture changed at different season if phosphate (P₂C₅) applied at 29.4g/(m².yr) or even higher.â…¤. Total phosphorus concentrations in the leachate were also related to phosphate (P₂C₅) application rates, Total phosphorus in the leachate increase with the accretion of phosphate (P₂O₅) application rate at July to September. Total phosphorus concentrations in the leachate reached maximum at August despite phosphate (P2O5) applied at various rates. T...