Abstract: To study different nitrogen application levels on the growth and nitrogen and phosphorus nutrient destination in a stitched hybrid turf， in this study we used tall fescue （Festuca arundinacea） variety ‘crossfireIV’ as the test material， and set the nitrogen level treatments of 1 g·m^-2， 3 g·m^-2， 5 g·m^-2 and 7 g·m^-2， and no nitrogen treatment was used as control. The effects of nitrogen application levels on the turf quality， growth rate and biomass of stitched hybrid turf， the absorption of nitrogen and phosphorus nutrients， the residues of nitrogen and phosphorus nutrients in soil and the leaching losses of nitrogen and phosphorus nutrients were measured. The results showed that with the increase of nitrogen application rate， the improvement of turf quality was greater in 1-2 months after turf formation. However， in the third month， the high nitrogen treatment group （5 g·m^-2 and 7 g·m^-2 per month） significantly accelerated the growth rate of turf grass， but also led to the excessive growth of turf. Under the condition of 3 g·m^-2 nitrogen application per month， the coverage， density， NDVI， color of turf grass and turfgrass verdure dry weight were the highest.The underground biomass of turfgrass was decreased under high nitrogen application， and the root dry weight of 10-20 cm in turfgrass under nitrogen application per 3 g·m^-2 was increased by 63.2% and 189.9% compared with 5 g·m^-2 and 7 g·m^-2， respectively. With the increase of nitrogen application level， nitrogen and phosphorus uptake of turf grass increased， nitrogen residue in soil increased， nitrogen leaching loss also increased， but nitrogen use efficiency decreased. When the monthly nitrogen application rate was greater than or equal to 5 g·m^-2， the total nitrogen leaching amount of lawn increased significantly， and the monthly nitrogen application rate of 5 g·m^-2 and 7 g·m^-2 increased by 250% and 650% compared with 3 g·m^-2， respectively. The nitrogen uses efficiency of turf decreased significantly， and the monthly nitrogen application of 5 g·m^-2 and 7 g·m^-2 decreased by 12.4% and 24.0%， respectively， compared with that of 3 g·m^-2. There was no significant effect on phosphorus residue and leaching in turf soil under different nitrogen application treatments. Therefore， it is recommended to apply about 3 g·m^-2 nitrogen per month to a stitched hybrid turf.

Key words: Tall fescue, Stitched hybrid turf, Turf quality, Nutrient uptake, Nutrient residues, Nutrient leaching

摘要： 为研究施氮水平对植丝式混合草坪生长及氮磷养分去向的影响，本研究以高羊茅（Festuca arundinacea）品种‘交战IV’为试验材料，设置1 g·m^-2，3 g·m^-2，5 g·m^-2和7 g·m^-2 4个施氮水平，以不施氮处理为对照，研究不同施氮量对植丝式混合草坪生长、氮磷养分吸收、土壤中残留以及淋溶损失的影响。结果表明：在草坪成坪后1—2个月内，随施氮量的增加，草坪的坪观质量逐渐提升。但在第3个月时，高施氮处理组（每月5 g·m^-2和7 g·m^-2）显著加快了草坪草生长速度的同时也导致了草坪草徒长。每月3 g·m^-2施氮条件下草坪草盖度、密度、归一化差异植被指数（normalized differential vegetation index，NDVI）、色泽及草坪草留茬干重均最高。高施氮处理降低了草坪草地下部生物量，每月3 g·m^-2施氮条件下草坪10~20 cm根系干重较5 g·m^-2和7 g·m^-2分别增加了63.2%和189.9%。随着施氮量的增加，草坪草氮素和磷素吸收量增加，土壤中氮素残留量和淋溶损失量均增加，但氮素利用效率却有所下降。当每月施氮量大于或等于5 g·m^-2时，草坪氮素总淋溶量显著增加，每月施氮5 g·m^-2和7 g·m^-2较3 g·m^-2分别增加了250%和650%；草坪氮素利用效率显著降低，每月施氮5 g·m^-2和7 g·m^-2较3 g·m^-2分别下降了12.4%和24.0%。不同施氮处理对草坪土壤中磷素残留量和淋溶量无显著影响。因此推荐植丝式混合草坪每月施氮量在3 g·m^-2左右。

关键词: 高羊茅, 植丝式混合草坪, 草坪坪观质量, 养分吸收, 养分残留, 养分淋溶损失