Abstract: In order to clarify the soil nutrient changes during the turfgrass greenup period,promote the turfgrass to turn green ahead of time and prolong the overall green period,and improve the value of turf,this experiment was conducted in Hohhot experiment station from March 12 to April 29,2017 using local cool-season turfgrass ‘Daqingshan’ kentucky bluegrass (Poa pratensis L. ‘Daqingshan’). The soil indexes of organic matter,available phosphorus,available potassium,alkaline nitrogen,catalase and urease were determined by sampling at regular intervals of every 4 days,and three batches of samples were taken to determine the six soil parameters. The results showed that there was a certain correlation between the six parameters except urease in the depth of 0~20 cm and 20~40 cm soil,and the contents of available phosphorus,basic nitrogen and organic matter showed significant correlation,and the coefficient of variation of urease content was the highest and the coefficient of variation of available phosphorus was the lowest in 0~20 cm soil. Among the soil nutrients of 20~40 cm soil,the coefficient of variation of available potassium was the highest and that of urease was the smallest. Therefore,0~20 cm shallow soil is more suitable for the growth of turfgrass,and the enzyme activity can be enhanced by increasing the utilization rate of potassium and nitrogen fertilizers during the turfgrass greenup period,so as to promote the early greenup of turfgrass,and to prolong the green period.

Key words: Greenup period, Soil nutrients, Changing rules

摘要： 为明确返青期土壤养分变化规律，促进草坪草提前返青进而延长绿期，提高坪用价值，本试验自2017年3月12日至4月29日在呼和浩特市试验基地内本土冷季型草坪草‘大青山’草地早熟禾（Poa pratensis L. ‘Daqingshan’）种植区进行采样研究，每隔4天定时取样，共取样3批次重复，测定有机质、速效磷、速效钾、碱性氮、过氧化氢酶和脲酶6项土壤指标。结果表明：以草坪草返青期为时间节点，在0~20 cm和20~40 cm土壤中，6种元素间除脲酶外都存在一定的相关性；速效磷、碱性氮和有机质含量呈现差异性变化，三者之间具有显著的相关性；在0~20 cm土壤中，脲酶含量的变异系数最高，速效磷的变异系数最低；在20~40 cm土壤养分中，速效钾的变异系数最高，脲酶的变异系数最小。因此，0~20 cm浅层土壤更适宜草坪草生长，并且在草坪草萌发期间可通过提高钾肥、氮肥等利用率来增强酶活性，从而促进草坪草的提前返青以实现绿期延长。

关键词: 返青期, 土壤养分, 变化规律