人工草地建植对甘南高寒草甸草地生产力及土壤理化特征的影响

为明确重度退化草地经人工建植后土壤理化性质和草地初级生产力状况.以甘南州碌曲县典型退化高寒草甸为研究对象,采用70％垂穗披碱草(Elymus nutans)+30％黑麦草(Lolium multiflorum)混播的方式,结合整地和施肥2种措施,测定其土壤理化性质和草地初级生产力变化特征,探寻适宜的人工建植方式.结果表...

Effects of Artificial Grassland Construction on Grassland Productivity and Soil Physicochemical Properties in Alpine Meadow of Gannan

In order to clarify the changes of soil physicochemical properties and grassland primary productivity of severely degraded grassland after artificial construction,the mixed planting of 70%Elymus nutans+30%Lolium multifloru,combined with soil preparation and fertilization in the typical degraded alpine meadow of Luqu County,Gannan Prefecture.Soil physicochemical properties and the changes of grassland primary productivity were measured to explore a better artificial planting model.The results showed that nitrogen fertilizer had significant effects on the content of soil total nitrogen and alkali solution nitrogen,and microbial agent combined with nitrogen fertilizer had the best effect on increasing soil total phosphorus and available phosphorus contents.Fertilizer application improved grassland productivity.The biomass of forbs,Lolium multifloru and Elymus nutans were increased by 43.32%,25.87%and 60.21%,respectively,in the nitrogen fertilizer combined with microbial agent plots compared with that in the no-fertilization plots.And the biomass of hybrid grasses in the artificial ridging plots was increased by 33.13%compared with that in the no-ridging plots.The biomass of supplementary sowing,the biomass of forbs and the total biomass of aboveground and underground were positively correlated with soil alkali solution nitrogen,available phosphorus and available potassium.Based on the comprehensive analysis,the method of‘double ridge+nitrogen fertilizer combined with microbial agent’has the best effect on artificial planting of severely degraded alpine meadow in Gannan.