不同尿素施肥水平对北方混播草坪中土壤各形态氮的影响

Effects of Urea Application on Soil Nitrogen and Turf grass Growth in Mixed Cool Season Lawn

为研究北京地区冷季型草坪合理的施肥制度,了解尿素施用对混播草坪土壤中各形态氮的影响。通过土壤渗滤水采集装置试验,研究尿素施用对草地早熟禾和高羊茅的混播草坪的生长情况和对土壤中各形态氮素含量的影响。试验中尿素施用分为低氮(年施氮量为10g/m2,相当于尿素25g/m2)、中氮(年施氮量为25g/m2,相当于尿素62.5g/m2)、高氮(年施氮量为40g/m2,相当于尿素100g/m2)3个施肥水平。各处理中的尿素分别在春季和秋季平均施用。试验中最佳施肥量是:年施尿素62.5g/m2(相当于氮量为25g/m2),在该水平下,草坪草能迅速吸收氮素,促进草坪植物生长;试验得出,施用尿素的水平与实验后土壤中全氮、铵态氮、硝态氮和碱解氮含量并不呈正相关。

The purpose of this paper was to find a more suitable nitrogen application system for the cool season turf in Beijing area by using the lysimeter method. The effects of urea application on soil nitrogen and turf growth were studied. The result showed that in the experimental design, urea application takes three levels： low nitrogen （N 10 g/m^2）, medium nitrogen （N 25 g/m^2）, and high nitrogen （N 40 g/m^2）. All the nitrogen was equally divided into two （spring and fall） application in each treatment. During the field experiments, mixed lawn was fertilized equally twice a year, in spring and in autumn. After fertilized, different treatments had different growing conditions, meanwhile different treatments soil had different nitrogen contents. It shows for a good appearance and healthy turf, the proper annual urea application rate was about 62.5 g/m^2 （N 25 g/ m^2）. Under the treatment, the grass of the mixed lawn can absorb nitrogen swiftly and grow well. At the same time, the research also showed that there was no positive relationship .between the urea employment level and the content of total nitrogen, ammonium nitrogen and nitric nitrogen content in soil.