摘要
Background:Previous studies have surveyed golf courses to determine nitrogen(N)fertilizer application rates on golf courses,but no previous studies have attempted to quantify how efficiently golf courses use nitrogen.Methods:This study tests the ability of the growth potential(GP)N Requirement model as a benchmarking tool to predict a target level of N use on 76 golf courses in 5 regions of the US(Midwest,Northeast,East Texas,Florida,Northwest)and 3 countries in Europe(Denmark,Norway,UK).Results:The ratio of the golf course-wide N application rate to the GP N requirement prediction(termed the nitrogen efficiency score or NES)was 0.27,indicating that golf courses used 73%less N than predicted by the model.As such,the GP N Requirement model needs to be recalibrated to predict N use on golf courses.This was achieved by adjusting the Nmax coefficient in the model.N rates on golf courses were widely variable both within and across regions.All regions had a coefficient of variation in N rates of 0.46 or greater.Conclusions:The high variation in N rates,which is largely unexplained by climate,economic factors,grass type,and soil type,may be indicative of inefficient N use in golf course management.
