施肥对退化草地的重建和恢复有重要作用,以青藏高原典型嵩草(Kobresia)草甸为研究对象,采用正交试验设计,测定了植物全氮、全磷、全钾和土壤全氮、全磷、全钾、速效磷及速效钾,分析了植物N/P,N/K,P/K,土壤N/P,N/K,P/K等化学计量特征.结果表明:在H9施肥条件下,土壤全氮、全钾、土壤N/P为最大值,分别为13.80 g·kg-1,11.99 g·kg-1和16.16;在H5处理下,土壤速效磷、植物全磷达到最大值,分别为0.022 g· kg-1和9.18 g· kg-1;在H4处理下的植物全氮为最大值(108.38 g·kg-1);在H1处理下,植物全钾为最大值(17.84g·kg-1);在H4处理下,植物N/P,N/K为最大值,分别为17.78和7.06,施肥对植物养分的作用要大于土壤.因此,施肥能显著提高高寒草甸植物全氮、全磷及全钾质量分数,影响植物及土壤养分化学计量关系.
Fertilizer played an important role in the reestablishment and recover of degraded grassland.The mass fractions of soil total nitrogen,total phosphorus,total potassium,available phosphorus,available potassium,plant total nitrogen,total phosphorus,total potassium,available phosphorus and available potassium were tested for analyzing the effects of different fertilizing levels on the plant and soil nutrients at alpine meadow in this paper.Results showed that the mass fractions of plant total nitrogen,total potassium and soil N/P reached the maximum values at H9 treatment which were 13.80 g · kg-1,11.99 g · kg-1and 16.16,respectively.Soil available phosphorus and plant total phosphorus reached the maximums values at H5 treatment which were 0.022 g · kg-1 and 9.18 g · kg-1,respectively.Plant total nitrogen had the maximum values (108.38 g · kg-1) at H4 treatment and plant total potassium had the maximum values at H1 treatment.Plant N/P and N/K ratios had the maximum values at H4 treatment,which were 17.78and 7.06,respectively.Fertilizer was more important to plant nutrients than soil nutrients.These finds suggested that fertilizer significantly not only improved the total nitrogen,total phosphorus,total potassium,available phosphorus,available potassium contents of both plant and soil,but affected the stoichiometric relationship between plant and soil nutrients.