生态学报2025，Vol.45Issue(7)：3204-3217,14.DOI:10.20103/j.stxb.202406121366
氮磷施肥对退化禾草混播草地生产力和土壤理化性质的影响
Effects of nitrogen and phosphorus fertilization on grassland productivity and soil physicochemical properties of degraded grass-mixed grasslands
摘要
Abstract
Fertilization is crucial for restoring and enhancing the productivity of degraded grasslands;however,the enduring impacts of a one-time fertilizer application on the vegetation and soil quality in alpine grasslands are not well understood.This study sought to assess the long-term effects of a one-time application of nitrogen and phosphorus fertilizers on the vegetation and soil physicochemical properties in alpine perennial grass-mixed grasslands that have been established for over two decades.The experiment used a randomized block design with four levels each of nitrogen(N0:0,N1:50,N2:100,N3:200 kg N/hm2)and phosphorus fertilizers(P0:0,P1:65,P2:117,P3:210 kg P2O5/hm2),along with their combinations,yielding a total of 16 treatment combinations.Grassland productivity and soil physicochemical properties were assessed in the first and third year after fertilization(2021 and 2023,respectively).The findings indicated that the elevated nitrogen level(N3)notably enhanced aboveground biomass(AGB),as well as soil organic matter(SOM),available nitrogen(AN),and available phosphorus(AP)levels in 2021.The AGB was still significantly higher than the other treatments at medium and high phosphorus levels(P2 and P3),as well as AN,AP,and soil total phosphorus(TP)contents in 2023.There was a significant correlation between nitrogen and phosphorus fertilizers and AGB,SOM,and AN,respectively;phosphorus fertilizer showed a significant association with AP and total phosphorus(TP);nitrogen-phosphorus interactions substantially impacted SOM and total nitrogen(TN)levels,and inter-annual correlations were significantly linked to AGB,SOM,and AN,respectively.Nitrogen and phosphorus fertilizers promoted all measured indicators in 2021,while phosphorus fertilizers still significantly enhanced AGB,SOM,and TN in 2023,indicating that the legacy effect of phosphorus fertilizers was greater than that of nitrogen fertilizers.The structural equation model revealed that nitrogen fertilizer effects were most pronounced in the first year,especially at high nitrogen and medium phosphorus levels(200 kg N/hm2 and 117 kg P2O5/hm2),whereas phosphorus fertilizer significantly influenced AGB and indirectly increased below-ground biomass via available phosphorus in 2023.The effects of phosphorus fertilizers continued into the third year,particularly with the low-nitrogen and high-phosphorus combinations(50 kg N/hm2 paired with 117 and 210 kg P2O5/hm2),demonstrating greater endurance.Combining economic inputs,a single application of high phosphorus with low nitrogen yielded better fertilization and legacy effects.The results of the study can provide an important reference for cultivation and restoration practices in degraded mixed-grass alpine grasslands.关键词
氮磷施肥/混播草地/草地生产力/土壤理化性质/施肥遗留效应Key words
nitrogen and phosphorus addition/mixed-sowing cultivated grassland/grassland productivity/soil physical and chemical properties/fertilizer legacy effect引用本文复制引用
孟愉欣,刘婉婷,王正文,王俊杰,陈新栋,王世林,曹文侠..氮磷施肥对退化禾草混播草地生产力和土壤理化性质的影响[J].生态学报,2025,45(7):3204-3217,14.基金项目
国家牧草产业技术体系(CARS-34) （CARS-34）
